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Well, not really life, but life-enabling molecules. Still an interesting find as it could point to clues that life may in fact exist far out there somewhere.
http://news.yahoo.com/s/space/20100312/sc_space/lifeenablingmoleculesspottedinorionnebula
The chemical fingerprints of potentially life-building molecules have been detected in the Orion nebula by Europe's Herschel Space Observatory.
The Orion nebula is a nearby stellar nursery, brimming with gas, dust and infant stars. It is known to be one of the most prolific chemical factories in space, although the full extent of its chemistry and the pathways for molecule formation are not well understood.
Researchers have used one of Herschel's instruments, which looks at the cosmos in the far infrared wavelengths of light, to provide more insight into how organic molecules form in space.
By sifting through the pattern of spikes in Orion nebula's light signature, or spectrum, astronomers have identified a few common molecules that are precursors to life-enabling molecules, including water, carbon monoxide, formaldehyde, methanol, dimethyl ether, hydrogen cyanide, sulfur oxide and sulfur dioxide. Each spike in the spectrum corresponds to a particular molecule.
"This HIFI spectrum, and the many more to come, will provide a virtual treasure trove of information regarding the overall chemical inventory and on how organics form in a region of active star formation. It harbors the promise of a deep understanding of the chemistry of space once we have the full spectral surveys available," said Edwin Bergin of the University of Michigan and the principal investigator of the HEXOS Key Program on Herschel.
Because of Herschel's unique infrared observing abilities, this new spectrum is already an improvement on previous one's taken of the Orion nebula.
"We obtained this spectrum in a few hours and it already beats any other spectrum, at any other wavelength, ever taken of Orion," said Frank Helmich, Herschel HIFI principal investigator of SRON Netherlands Institute for Space Research.
Built by the European Space Agency, Herschel launched in May 2009 on a mission to scan the universe in the far-infrared range of the spectrum. The observatory is expected to last until 2012 and has the largest single mirror ever built for a space telescope.
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konadora
Singapore66158 Posts
But does having all the necessary elements -> life? I'm pretty shitty at chemistry but my thinking is that having the 'materials' there doesn't necessary mean the end products will exist.
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On March 14 2010 03:47 konadora wrote:
I'm more interested in how the observatory detected the molecules.
+ Show Spoiler +By sifting through the pattern of spikes in Orion nebula's light signature, or spectrum, astronomers have identified a few common molecules that are precursors to life-enabling molecules, including water, carbon monoxide, formaldehyde, methanol, dimethyl ether, hydrogen cyanide, sulfur oxide and sulfur dioxide. Each spike in the spectrum corresponds to a particular molecule.
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konadora
Singapore66158 Posts
Yeah I posted that before the edit
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If I remember correctly, each element emit a unique wavelength of light. I guess that's how scientists can tell apart from each molecules
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On March 14 2010 03:47 konadora wrote:
But does having all the necessary elements -> life? I'm pretty shitty at chemistry but my thinking is that having the 'materials' there doesn't necessary mean the end products will exist.
First off, that was covered in the first sentence of the OP.
Second, http://en.wikipedia.org/wiki/Abiogenesis companion reading material lolo
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Is spectrum analysis so accurate as to determine the exact compounds from such a huge distance?
Also "life" is an extreme overstatement in my opinion.
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Nice! I remember when they first discovered planets that have suitable conditions for life! Making pretty quick advances in science if you ask me.
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konadora
Singapore66158 Posts
Doesn't many other places of the universe contain the same elements? Or is that not the case? (genuine question here, I have no knowledge about space chemistry)
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when can we live on the moon damn it!
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Well, when they use the term life, it is used very lightly for any type of life (single cell life came very quickly in our universe for example). If they find single cell life else where in the universe, then there is a good chance many million/billion of years from now their could be multi-cellular life.
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On March 14 2010 03:50 jjkxdummy wrote:
If I remember correctly, each element emit a unique wavelength of light. I guess that's how scientists can tell apart from each molecules
That's not entirely true, each element will emit absorb certain bands of light when ionized (to free electrons from their shells), and those elements will emit those same bands as the ion captures electrons into those same energy states. There's massive databases on the light signatures of different atoms and molecules, and you can check missing wavelengths for signs of absorption or spiked wavelengths for signs of capture against the database of known elements. These signatures are known as emission spectra, http://en.wikipedia.org/wiki/Emission_spectrum
Interesting story, helium was originally thought to be a metal existing only on the sun because it had a wavelength signature that was different from any known discovered element on earth (thus the name, helios = sun and ium = suffix for metals). http://en.wikipedia.org/wiki/Helium#Scientific_discoveries
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Thing is, scientists can discover all of the life galaxies they are, but they need to find us a way to get there...before time is up
I am a believer in aliens, and i think that they need the same things we need (water, sunlight and all) so this is encouraging
in my opinion science needs to find a way to get us to these "life galaxies" instead of just finding them and publishing stuff about it...which is still interesting
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What?! There might be life somewhere besides our one spec of the unbelievably enormous universe?!
News to me.
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On March 14 2010 04:05 Housemd wrote:
Thing is, scientists can discover all of the life galaxies they are, but they need to find us a way to get there...before time is up
I am a believer in aliens, and i think that they need the same things we need (water, sunlight and all) so this is encouraging
in my opinion science needs to find a way to get us to these "life galaxies" instead of just finding them and publishing stuff about it...which is still interesting
You're talking as if the same group of scientists are responsible for finding life and improving transportation. What? The two issues are completely different, and the fact that these scientists found some life-related molecules doesn't mean other scientists aren't trying to develop transportation.
EDIT: And as a matter of personal opinion, getting living humans to the closest solar system, let alone a life-sustaining galaxy, seems pretty impossible. Relativistic effects help you on the front of time, but it also makes the entire universe extremely hazardous.
EDIT2: Also, science doesn't work like some sort of game where you can click "research intergalactic transportation" and have it up and running in x years. Much of the field, especially the "cutting-edge" is dependent on complete chance: without theoretical knowledge, nothing effective can be engineered. Without observation, testing, and data, no theoretical models can be made. Two hundred years ago, "chemistry" was still glorified alchemy without knowledge of discrete energy states, the existence of electrons, etc etc. What makes you think human knowledge isn't on the complete whims of chance? (sorry, "science needs to find a way to X instead of Y" just really makes me rage, especially when Y involves a lot more actual science than X)
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Nice article, but the title is completely thoroughly dead wrong. Organic molecules aren't life and definitely not *life* and the Orion nebula is definitely not in another galaxy, wtf 
Also it's not wholly unexpected since the Orion nebula is just the star-forming region in a larger molecular cloud which has traces of all kinds of organic molecules. This just confirms something a lot of scientists suspected already.
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The only way to travel farther than our solar system is through time travel. Therefore, we need the technology to "grab" light and pull it back. The speed of light is what limits our ability of time-travelling.
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On March 14 2010 03:53 barth wrote:
Is spectrum analysis so accurate as to determine the exact compounds from such a huge distance? [1]
Also "life" is an extreme overstatement in my opinion. [2]
[1] Short answer: yes.
Spectrum analysis is, in theory, a way to identify any compound. Now, the things that we can actually measure practically very easily are things like single atoms or 'small' compounds (compounds made up of a small number of different elements). So stuff like Hydrogen, Helium, Nitrogen etc. is easily identified 100% of the time. Getting into larger compounds sort of stretches the limits of computational power. The calculations required to determine what spectra a compound produces are enormous and extremely complicated (lots of very advanced quantum mechanics).
However, once you have the spectra (once you've spent your couple of weeks time on a supercomputer), you have it. You know it, and it will always be correct. The cool thing about atomic spectra is that quantum mechanics gives an enormous amount of constraints on what spectra can be produced - so each atomic configuration + energy configuration can only have a single spectra. This is why spectrum analysis can give 100% identification of a compound, assuming you've already calculated the answer and can relate it to something you've measured.
[2] It is, especially in this case. I think this particular article is overhyped. However, something that is required for basic building blocks of life exists pretty much everywhere except for regions with black holes or other extremely high-energy radiation producers - PAHs (polycyclic aromatic hydrocarbons). The great thing about PAHs is that
a) They are fucking everywhere.
b) They are extremely stable.
c) They are a bit of nitrogen away from being amino acids.
So, one thing I could say about this article is this: an area with all of those great elements in particularly high abundance is definitely worth looking at. Because PAHs already exist everywhere, and having all those other nice elements already in place just makes it that much more likely that life will form there in some fashion.
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On March 14 2010 04:29 LuCky. wrote:
The only way to travel farther than our solar system is through time travel. Therefore, we need the technology to "grab" light and pull it back. The speed of light is what limits our ability of time-travelling.
That's not true either. Stop making things up. I'll go statement by statement.
"The only way to travel farther than our solar system is through time travel."
First off, the nearest star other than the sun is 4.24 light years away. That means if you travelled at 99% the speed of light, it wouldn't take that long. DEBUNKED. I'll go on though. Even if something were 150 light years away, if you traveled at a sufficient speed, time dilation (http://en.wikipedia.org/wiki/Time_dilation) would make it so time goes slower in your reference frame, so you could pull it off in 80 years if you're fast enough.
"Therefore, we need the technology to "grab" light and pull it back."
You mean like a black hole? What are you talking about? The speed of light is the same constant in all reference frames, you can't change a fundamental constant of the universe with something inside the universe. DEBUNKED.
"The speed of light is what limits our ability of time-travelling."
Okay so if the speed of light were faster, then it would still be the fastest possible speed. The speed of light is a fundamental constant that's a property of the universe, and one important property of that speed is that nothing can travel faster. (except the spacetime fabric itself and entanglement-related information, apparently)
Where did you learn all this? I'm interested to hear what you think of as a credible source.
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1) That 'pull back light' post is hilarious.
2) Scientists have been pretending that finding methane in any atmosphere is a sure sign of life because they don't believe that methane can be produced without being degraded without life.
Once you learn how extrapolation and assumption heavy astrobiology is you kinda get a distaste for the entire thing. That said, as instrumentation gets better and we get more planetary samples for analysis things will shape up considerably.
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Also our bias of what life is causes us to think there is only one type of chemistry by which 'life' can exist. For all we know there could be beings who are made of entirely different chemistry than our own - As the great Carl Sagan mentioned
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On March 14 2010 04:39 liosama wrote:
Also our bias of what life is causes us to think there is only one type of chemistry by which 'life' can exist. For all we know there could be beings who are made of entirely different chemistry than our own - As the great Carl Sagan mentioned
I bet they're all made of Starcraft and they play koreans
(I know makes zero sense)
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intrigue
Washington, D.C9933 Posts
orion nebula is really close by, huh? cool. also, i wonder what kind of resolution the spectrometer they use for galaxies has, how the hell do you tell anything is there through the noise?
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On March 14 2010 04:29 LuCky. wrote:
The only way to travel farther than our solar system is through time travel. Therefore, we need the technology to "grab" light and pull it back. The speed of light is what limits our ability of time-travelling.
Errrr... no it doesn't. We theorize that it does because of our understanding of physics, but we've never been able to test it.
We understand a significant portion about the world we live in, including electromagnetic energy, physics, and chemistry. But the one thing we haven't really got a grasp on that would be relevant to this discussion is gravity. All of our math seems to be wrong when it comes to that force, and it's theorized that if we ever make a breakthrough that complements or replaces our theory of general relativity, we can bend space to our will (funnily enough, much like the Protoss :p /nerd )
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On March 14 2010 04:34 DefMatrixUltra wrote:Show nested quote +On March 14 2010 03:53 barth wrote:
Is spectrum analysis so accurate as to determine the exact compounds from such a huge distance? [1]
Also "life" is an extreme overstatement in my opinion. [2] [1] Short answer: yes. Spectrum analysis is, in theory, a way to identify any compound. Now, the things that we can actually measure practically very easily are things like single atoms or 'small' compounds (compounds made up of a small number of different elements). So stuff like Hydrogen, Helium, Nitrogen etc. is easily identified 100% of the time. Getting into larger compounds sort of stretches the limits of computational power. The calculations required to determine what spectra a compound produces are enormous and extremely complicated (lots of very advanced quantum mechanics). However, once you have the spectra (once you've spent your couple of weeks time on a supercomputer), you have it. You know it, and it will always be correct. The cool thing about atomic spectra is that quantum mechanics gives an enormous amount of constraints on what spectra can be produced - so each atomic configuration + energy configuration can only have a single spectra. This is why spectrum analysis can give 100% identification of a compound, assuming you've already calculated the answer and can relate it to something you've measured.
While nothing you say is really wrong, I think you're kind of oversimplifying things.
There are many different types of transitions that molecules can undergo. The ones that are generally examined are:
Rotational (less than 0.01 of an electronvolt, or eV)
Vibrational (a few tenths of an electronvolt)
Electronic (several eV)
The vibrational excitation of molecules happens into the IR region (IR also is known as thermal energy) of the electromagnetic spectrum. However, the molecule must have a dipole moment, or else it will not absorb infrared energy. So you would never see nitrogen in an IR spectrum, nor would you see individual atoms. However, even something as simple as water can be seen (at around 3200-3500 wavenumbers, which is just an inverse centimeter and a unit of energy).
Electronic transitions correspond to the visible and ultraviolet part of the electromagnetic spectrum. If you wanted to look at emissions of atoms though, you'd put everything in a flame or furnace. I somehow doubt that emission spectroscopy of atoms in space would be an easy thing. Although after reading the documentation about the instruments, apparently there are some metastable atomic transitions in the near IR... which I was not aware of (I can't imagine these are easy to see though).
As far as accuracy goes, as long as the absorption is strong enough, then you know something is there, so long as you already know its absorptions. Although generally speaking, IR is only used for identifying what functional groups are present, each individual spectrum is unique, so you can back out what is present based on known spectra, to some extent (although there are generally easier methods, if you have a purified sample to work with... nuclear magnetic resonance spectroscopy (NMR) or mass spectrometry, for example).
But in this case, everything is so simple, it would be fairly trivial to look at a spectra and say "oh, water and carbon dioxide is there!"
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On March 14 2010 04:57 VorcePA wrote:Show nested quote +On March 14 2010 04:29 LuCky. wrote:
The only way to travel farther than our solar system is through time travel. Therefore, we need the technology to "grab" light and pull it back. The speed of light is what limits our ability of time-travelling. All of our math seems to be wrong when it comes to that force, and it's theorized that if we ever make a breakthrough that complements or replaces our theory of general relativity, we can bend space to our will (funnily enough, much like the Protoss :p /nerd )
Um, our math is only wrong when it comes to trying to mix gravity/generalrelativity with quantum mechanics. It also doesn't fully explain the behaviors of some galaxies, but that's where dark matter (mass distribution of galaxies) / dark energy (accelerated expansion of the universe) / dark flow (some parts of the universe going in a weird direction) come in, just placeholders until we understand what the hell's going on there. To say that "all of our math seems to be wrong when ti comes to that force" is a bit of an exaggeration...
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On March 14 2010 04:57 VorcePA wrote:Show nested quote +On March 14 2010 04:29 LuCky. wrote:
The only way to travel farther than our solar system is through time travel. Therefore, we need the technology to "grab" light and pull it back. The speed of light is what limits our ability of time-travelling. Errrr... no it doesn't. We theorize that it does because of our understanding of physics, but we've never been able to test it. We understand a significant portion about the world we live in, including electromagnetic energy, physics, and chemistry. But the one thing we haven't really got a grasp on that would be relevant to this discussion is gravity. All of our math seems to be wrong when it comes to that force, and it's theorized that if we ever make a breakthrough that complements or replaces our theory of general relativity, we can bend space to our will (funnily enough, much like the Protoss :p /nerd )
I am a physicist. Almost everything you are saying is nonsense.
We have a really great understanding of gravity. Even just using plain old Newtonian gravity solves pretty much any problem that we could be presented with. Gravity was the first of the forces that we started studying, look at the n-body problem.
General relativity already shows us that solutions exist where we can 'bend space to our will' by warping spacetime in order to travel 'globally' faster than light (but not locally). The only thing we don't have is a quantum theory of gravity, which as far as we can tell is primarily of interest for understanding the early formation of the universe.
I'm not saying that we know everything and we've got this shit figured out, but please don't post garbage like this without even trying (like pointing at some crackpot's paper [Null physics anyone?]).
On March 14 2010 05:07 zer0das wrote:Show nested quote +On March 14 2010 04:34 DefMatrixUltra wrote:On March 14 2010 03:53 barth wrote:
Is spectrum analysis so accurate as to determine the exact compounds from such a huge distance? [1]
Also "life" is an extreme overstatement in my opinion. [2] [1] Short answer: yes. Spectrum analysis is, in theory, a way to identify any compound. Now, the things that we can actually measure practically very easily are things like single atoms or 'small' compounds (compounds made up of a small number of different elements). So stuff like Hydrogen, Helium, Nitrogen etc. is easily identified 100% of the time. Getting into larger compounds sort of stretches the limits of computational power. The calculations required to determine what spectra a compound produces are enormous and extremely complicated (lots of very advanced quantum mechanics). However, once you have the spectra (once you've spent your couple of weeks time on a supercomputer), you have it. You know it, and it will always be correct. The cool thing about atomic spectra is that quantum mechanics gives an enormous amount of constraints on what spectra can be produced - so each atomic configuration + energy configuration can only have a single spectra. This is why spectrum analysis can give 100% identification of a compound, assuming you've already calculated the answer and can relate it to something you've measured. While nothing you say is really wrong, I think you're kind of oversimplifying things. [1] There are many different types of transitions that molecules can undergo. The ones that are generally examined are: Rotational (less than 0.01 of an electronvolt, or eV) Vibrational (a few tenths of an electronvolt) Electronic (several eV) The vibrational excitation of molecules happens into the IR region (IR also is known as thermal energy) of the electromagnetic spectrum. However, the molecule must have a dipole moment, or else it will not absorb infrared energy. So you would never see nitrogen in an IR spectrum, nor would you see individual atoms. However, even something as simple as water can be seen (at around 3200-3500 wavenumbers, which is just an inverse centimeter and a unit of energy). Electronic transitions correspond to the visible and ultraviolet part of the electromagnetic spectrum. If you wanted to look at emissions of atoms though, you'd put everything in a flame or furnace. I somehow doubt that emission spectroscopy in space would be an easy thing. [2]
[1] Answering a post on a non-physics forum, it's pretty much impossible to not oversimplify things. It seems like you are speaking from a chemistry/thermodynamics perspective. I have actually worked with astrophysicists on these spectral analysis problems (correcting for redshift and everything).
[2] It is very difficult. That's why we can't do a simple analysis on most of the things we're looking for. You have to calculate the spectra from quantum mechanics (you can't just assume your particles are in a boiler or whatever). Once you correct for redshift and doppler effect, you can get an identification 100% of the time, assuming the spectra is something familiar or something you have calculated already.
I addressed most of your explanation in my "atomic configuration + energy configuration can only have a single spectra" without trying to explain the different modes that complex compounds can have.
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On March 14 2010 05:07 SpiritoftheTunA wrote:Show nested quote +On March 14 2010 04:57 VorcePA wrote:On March 14 2010 04:29 LuCky. wrote:
The only way to travel farther than our solar system is through time travel. Therefore, we need the technology to "grab" light and pull it back. The speed of light is what limits our ability of time-travelling. All of our math seems to be wrong when it comes to that force, and it's theorized that if we ever make a breakthrough that complements or replaces our theory of general relativity, we can bend space to our will (funnily enough, much like the Protoss :p /nerd ) Um, our math is only wrong when it comes to trying to mix gravity/generalrelativity with quantum mechanics. It also doesn't fully explain the behaviors of some galaxies, but that's where dark matter (mass distribution of galaxies) / dark energy (accelerated expansion of the universe) / dark flow (some parts of the universe going in a weird direction) come in, just placeholders until we understand what the hell's going on there. To say that "all of our math seems to be wrong when ti comes to that force" is a bit of an exaggeration...
I'm pretty sure making up placeholders for over 95% of the mass in the universe constitutes us being more wrong than right.
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On March 14 2010 05:16 VorcePA wrote:Show nested quote +On March 14 2010 05:07 SpiritoftheTunA wrote:On March 14 2010 04:57 VorcePA wrote:On March 14 2010 04:29 LuCky. wrote:
The only way to travel farther than our solar system is through time travel. Therefore, we need the technology to "grab" light and pull it back. The speed of light is what limits our ability of time-travelling. All of our math seems to be wrong when it comes to that force, and it's theorized that if we ever make a breakthrough that complements or replaces our theory of general relativity, we can bend space to our will (funnily enough, much like the Protoss :p /nerd ) Um, our math is only wrong when it comes to trying to mix gravity/generalrelativity with quantum mechanics. It also doesn't fully explain the behaviors of some galaxies, but that's where dark matter (mass distribution of galaxies) / dark energy (accelerated expansion of the universe) / dark flow (some parts of the universe going in a weird direction) come in, just placeholders until we understand what the hell's going on there. To say that "all of our math seems to be wrong when ti comes to that force" is a bit of an exaggeration... I'm pretty sure making up placeholders for over 95% of the mass in the universe constitutes us being more wrong than right.
No, because saying that gravity doesn't account for that "mass" is like saying "wtf gravity is so strong between two electrons, AND IT REPELS." What I'm saying is that that 95% of missing "mass" might not necessarily be governed by our existing theories of gravity and relativity. Just because we say "adding invisible mass in these locations would make gravity make sense" doesn't mean that it has to be gravity that's the inconsistency.
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oh thank god, i was gonna give up on this thread :/
Spectroscopy is nice but just finding organic molecules is not life; they are a prerequisite but there are many others. It's like digging up some iron ore and saying HEY GUYS I FOUND A CAR.
To find signs of actual life in other galaxies you'd need to be able to resolve a planet to do spectroscopy on it, which is really really hard. Planets are something like 10^-10 arcseconds at most and the best we can do is 10^-3 or so.
Otherwise we would probably have to find evidence of actual civilizations, which means they either have to be aiming a signal directly at us or have a power output close to that of a star.
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On March 14 2010 05:21 starfries wrote:
oh thank god, i was gonna give up on this thread :/
Spectroscopy is nice but just finding organic molecules is not life; they are a prerequisite but there are many others. It's like digging up some iron ore and saying HEY GUYS I FOUND A CAR.
To find signs of actual life in other galaxies you'd need to be able to resolve a planet to do spectroscopy on it, which is really really hard. Planets are something like 10^-10 arcseconds at most and the best we can do is 10^-3 or so.
Otherwise we would probably have to find evidence of actual civilizations, which means they either have to be aiming a signal directly at us or have a power output close to that of a star.
Luckily for us, the Earth would appear as a huge anomaly in certain frequencies, so if there's any other intelligent life in the universe, they might look at us and go "wtf is going on there." (Not counting the fact that if they were millions of light years away, then they'd only receive that information millions of years from now)
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gravity more imba than roaches
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On March 14 2010 03:47 konadora wrote:
But does having all the necessary elements -> life? I'm pretty shitty at chemistry but my thinking is that having the 'materials' there doesn't necessary mean the end products will exist.
Having all the necessary elements is still a breakthrough; does having all the DNA needed for humans make a human? probably not, but over time....
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HnR)hT
United States3468 Posts
On March 14 2010 04:37 L wrote:
1) That 'pull back light' post is hilarious.
2) Scientists have been pretending that finding methane in any atmosphere is a sure sign of life because they don't believe that methane can be produced without being degraded without life.
Once you learn how extrapolation and assumption heavy astrobiology is you kinda get a distaste for the entire thing. That said, as instrumentation gets better and we get more planetary samples for analysis things will shape up considerably.
Astrobiology is not a real scientific discipline. 
Also, AFAIK there can't possibly be life as we understand it in a region of young stars and interstellar gas. Aside from the fact such stars presumably had not had the time to aquire planetary systems with Earth-like planets, they occupy a region well on the left on the main sequence strip of the Hertzprung-Russel diagram, i.e. they are blue-hot and extremely luminous and their radiation would be absolutely lethal at distances in the AUs.
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On March 14 2010 05:16 VorcePA wrote:Show nested quote +On March 14 2010 05:07 SpiritoftheTunA wrote:On March 14 2010 04:57 VorcePA wrote:On March 14 2010 04:29 LuCky. wrote:
The only way to travel farther than our solar system is through time travel. Therefore, we need the technology to "grab" light and pull it back. The speed of light is what limits our ability of time-travelling. All of our math seems to be wrong when it comes to that force, and it's theorized that if we ever make a breakthrough that complements or replaces our theory of general relativity, we can bend space to our will (funnily enough, much like the Protoss :p /nerd ) Um, our math is only wrong when it comes to trying to mix gravity/generalrelativity with quantum mechanics. It also doesn't fully explain the behaviors of some galaxies, but that's where dark matter (mass distribution of galaxies) / dark energy (accelerated expansion of the universe) / dark flow (some parts of the universe going in a weird direction) come in, just placeholders until we understand what the hell's going on there. To say that "all of our math seems to be wrong when ti comes to that force" is a bit of an exaggeration... I'm pretty sure making up placeholders for over 95% of the mass in the universe constitutes us being more wrong than right.
Just because the theory doesn't explain everything doesn't mean that there are amazing space-bending abilities to be had. When Einstein came up with relativity it wasn't like we started building time machines since the previous theories were basically right EXCEPT in high gravitational fields and at near-light speeds. So any new theory of quantum gravity will look basically the same, except for very small things in high gravitational fields/high speeds.
Even if it allows things like teleportation, it would probably only work on particles, certain quantum states, or exotic matter. None of which would apply to spaceships. So we would still have to get there the long way. Even being able to make wormholes still means we have to get the thing out there somehow, which is limited by the speed of gravitational waves (= c).
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On March 14 2010 05:14 DefMatrixUltra wrote:[[2] It is very difficult. That's why we can't do a simple analysis on most of the things we're looking for. You have to calculate the spectra from quantum mechanics (you can't just assume your particles are in a boiler or whatever). Once you correct for redshift and doppler effect, you can get an identification 100% of the time, assuming the spectra is something familiar or something you have calculated already.
Yeah, I realize you have to simplify things a bit, I just think you went a little overboard. 
Also, you must calculate the spectra? Is there any particular reason for this? Are real spectra too noisy? (actually now that I think about it, probably since IR detectors have this issue :S Although I suspect there's probably other reasons too..).
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I think we should launch a preemptive nuke. It should reach by the time intelligent multicellular life develops.
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On March 14 2010 05:46 Slow Motion wrote:
I think we should launch a preemptive nuke. It should reach by the time intelligent multicellular life develops.
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The Orion nebula is part of our galaxy, the thread title is misleading 
It is just the nearest big star formation region. That is also the reason why it is so prominent in the sky. Massive young stars are very bright.
Herschel is pretty new though, and I am certain it does produce the best spectra ever in far-infrared. It´s pretty amazing to have a european 3.5m-telescope in space, that has a larger mirror than Hubble after all. A far-infrared-telescope is a little different from an optical telescope though.
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On March 14 2010 05:53 Tenryu wrote:Show nested quote +On March 14 2010 05:46 Slow Motion wrote:
I think we should launch a preemptive nuke. It should reach by the time intelligent multicellular life develops.
Haha, the orion nebula is a star-forming region, supernovae are guaranteed to happen soon (on astronomical timescales) and in fact did happen already. A nuke would be like nothing against a supernova.
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On March 14 2010 03:47 konadora wrote:
But does having all the necessary elements -> life? I'm pretty shitty at chemistry but my thinking is that having the 'materials' there doesn't necessary mean the end products will exist.
Exactly, like you can't just throw together water, carbon, nitrogen, phosphorous, etc. and you end up with a human.
I think quite obviously there are chemicals out there that form the basis of life on earth, we have already seen that from analysing meteors.
EDIT: AFAIK
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On March 14 2010 06:05 iCCup.deL wrote:Show nested quote +On March 14 2010 03:47 konadora wrote:
But does having all the necessary elements -> life? I'm pretty shitty at chemistry but my thinking is that having the 'materials' there doesn't necessary mean the end products will exist. Exactly, like you can't just throw together water, carbon, nitrogen, phosphorous, etc. and you end up with a human. I think quite obviously there are chemicals out there that form the basis of life on earth, we have already seen that from analysing meteors.
Organic molecules in nebulae are nothing new really, hell we know there is lots of alcohol out there  This spectrum is just of better quality.
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On March 14 2010 05:40 zer0das wrote:Show nested quote +On March 14 2010 05:14 DefMatrixUltra wrote:[[2] It is very difficult. That's why we can't do a simple analysis on most of the things we're looking for. You have to calculate the spectra from quantum mechanics (you can't just assume your particles are in a boiler or whatever). Once you correct for redshift and doppler effect, you can get an identification 100% of the time, assuming the spectra is something familiar or something you have calculated already. Yeah, I realize you have to simplify things a bit, I just think you went a little overboard. Also, you must calculate the spectra? Is there any particular reason for this? Are real spectra too noisy? (actually now that I think about it, probably since IR detectors have this issue :S)
For stuff like Hydrogen and Helium, you do not have to calculate the spectra (we already know what it looks like from simple lab experiments). Even if you did, it's pretty easy for these simple atoms.
Also, when you take a spectral measurement series for something like a galaxy, you can make broad sweeps and just say 'this is H alpha' and so on without any real work needed.
However, most astronomers these days are looking for specific things. Noise is not a huge problem in the signals (we're in space, so there's not any background radiation if we're far enough away from the Earth and we're not looking straight at Mars or something), and you can take measurements over very small frequency ranges and then add them all together later to get the spectrum. The special stuff you are looking for (for example, PAHs) is in general a very complicated system (with 50-100 atoms combining in many different ways).
+ Show Spoiler [More science] +
The difficulty with these complicated systems is that they have spectra over large ranges. You can't look at a single molecule of a compound in a certain state and be like 'oh this is in its n-th rotational mode with extra vibrational noise' or whatever (you can do this in a lab, but not in space). You will get a spectrum from a LOT of emissions happening all at once (remember, the resolution here is pretty important).
This is why you have to run the calculations. You have to put in the number of molecules, the chemical makeup, the molecular bonding structure etc. and solve for it at every energy level between the lowest and highest possible levels you are interested in. This is a huge calculation.
Keep in mind that this calculation must be done, in general, BEFORE you try to compare measurements. So you have to go out, measure a spectrum, and then try to guess which configuration its in, and then calculate it and see if you are right. We've already done a bunch of calculations for the 'smaller' configurations so we already have a lot of them.
One important thing is that a lot of these classes of atomic structures all look the same except at some particular range (like they are within 1-5% of each other except in some special range where their unique modes show up). So we need to do the calculations over a very large range of energy levels to find spaces where the unique modes show up.
But anyway, in summary, astronomical spectroscopy is a very advanced field and is definitely capable of identifying things at ridiculous distances thanks to the constraints that quantum mechanics puts on the combinations of elements. It's hard for large stuff, and easy for simple small stuff.
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On March 14 2010 06:09 Maenander wrote:Show nested quote +On March 14 2010 06:05 iCCup.deL wrote:On March 14 2010 03:47 konadora wrote:
But does having all the necessary elements -> life? I'm pretty shitty at chemistry but my thinking is that having the 'materials' there doesn't necessary mean the end products will exist. Exactly, like you can't just throw together water, carbon, nitrogen, phosphorous, etc. and you end up with a human. I think quite obviously there are chemicals out there that form the basis of life on earth, we have already seen that from analysing meteors. Organic molecules in nebulae are nothing new really, hell we know there is lots of alcohol out there This spectrum is just of better quality.
mmm booze comets
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Lol, so are the things living there always drunk?
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On March 14 2010 05:34 HnR)hT wrote:Show nested quote +On March 14 2010 04:37 L wrote:
1) That 'pull back light' post is hilarious.
2) Scientists have been pretending that finding methane in any atmosphere is a sure sign of life because they don't believe that methane can be produced without being degraded without life.
Once you learn how extrapolation and assumption heavy astrobiology is you kinda get a distaste for the entire thing. That said, as instrumentation gets better and we get more planetary samples for analysis things will shape up considerably. Astrobiology is not a real scientific discipline. Also, AFAIK there can't possibly be life as we understand it in a region of young stars and interstellar gas. Aside from the fact such stars presumably had not had the time to aquire planetary systems with Earth-like planets, they occupy a region well on the left on the main sequence strip of the Hertzprung-Russel diagram, i.e. they are blue-hot and extremely luminous and their radiation would be absolutely lethal at distances in the AUs.
Sure it is. Its just in its infancy.
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@L
I believe the methane found in the Mars-atmosphere last year is a strong indication that methane is not the best indicator for life on a planet, although many Mars-enthusiasts might disagree
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On March 14 2010 06:03 Maenander wrote:Show nested quote +On March 14 2010 05:53 Tenryu wrote:On March 14 2010 05:46 Slow Motion wrote:
I think we should launch a preemptive nuke. It should reach by the time intelligent multicellular life develops. Haha, the orion nebula is a star-forming region, supernovae are guaranteed to happen soon (on astronomical timescales) and in fact did happen already. A nuke would be like nothing against a supernova.
LOL it'd be like trying to 4 pool someone.. but the map is so big that when you get there, they stop it with 3/3 battlecruisers
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United States24670 Posts
On March 14 2010 06:34 starfries wrote:Show nested quote +On March 14 2010 06:03 Maenander wrote:On March 14 2010 05:53 Tenryu wrote:On March 14 2010 05:46 Slow Motion wrote:
I think we should launch a preemptive nuke. It should reach by the time intelligent multicellular life develops. Haha, the orion nebula is a star-forming region, supernovae are guaranteed to happen soon (on astronomical timescales) and in fact did happen already. A nuke would be like nothing against a supernova. LOL it'd be like trying to 4 pool someone.. but the map is so big that when you get there, they stop it with 3/3 battlecruisers
Wasn't that iloveoov's pimpest play?
Btw thread has been /threaded already.
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On March 14 2010 03:53 barth wrote:
Is spectrum analysis so accurate as to determine the exact compounds from such a huge distance?
Also "life" is an extreme overstatement in my opinion.
Not really, all you need is a single-celled organism to form and that will be considered life.
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"Scientists discover *life* on another galaxy."
isn't orion nebula part of the milky way?
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On March 14 2010 06:05 iCCup.deL wrote:Show nested quote +On March 14 2010 03:47 konadora wrote:
But does having all the necessary elements -> life? I'm pretty shitty at chemistry but my thinking is that having the 'materials' there doesn't necessary mean the end products will exist. Exactly, like you can't just throw together water, carbon, nitrogen, phosphorous, etc. and you end up with a human. I think quite obviously there are chemicals out there that form the basis of life on earth, we have already seen that from analysing meteors. EDIT: AFAIK
heh, this reminds me of the miller/urey experiment.
http://en.wikipedia.org/wiki/Miller–Urey_experiment
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On March 14 2010 06:43 hifriend wrote:
"Scientists discover *life* on another galaxy."
isn't orion nebula part of the milky way?
Yes, the orion region is one of the closest red blots on this picture, around 1300 lightyears away from the sun:
nice map of the milky way, ah the things NASA does for us
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On March 14 2010 06:36 micronesia wrote:Show nested quote +On March 14 2010 06:34 starfries wrote:On March 14 2010 06:03 Maenander wrote:On March 14 2010 05:53 Tenryu wrote:On March 14 2010 05:46 Slow Motion wrote:
I think we should launch a preemptive nuke. It should reach by the time intelligent multicellular life develops. Haha, the orion nebula is a star-forming region, supernovae are guaranteed to happen soon (on astronomical timescales) and in fact did happen already. A nuke would be like nothing against a supernova. LOL it'd be like trying to 4 pool someone.. but the map is so big that when you get there, they stop it with 3/3 battlecruisers Wasn't that iloveoov's pimpest play? Btw thread has been /threaded already.
Yeah that one was legendary. I think it was #2 in that year, even beating Boxer building a supply depot
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I hope there is life out there.
I also hope that that life won't zerg rush us.
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As the previous posters said, just cause you have organic molecules that are components of living organisms doesn't mean that there will be or there is life. Just like taking a watch, hammering it to pieces, and saying that if we wait long enough it'll turn back into a working watch. Or as starfries said about iron ore not equivalent to a car.
I'm not bashing that life can't exist out there in the near-infinite universe, I'm just saying that they're overhyping their findings.
For instance, it's been extensively theorized that silicon based lifeforms could exist in the same way as carbon based lifeforms do. Their chemistry would be immensely different, but it could still be 'life'.
On the bright side, if we ever screw up Earth enough and we need a new home, we can find a wormhole, hop over to there, colonize some planets and play some EVE Online.
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Wake me up when the Xel'naga get here
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Russian Federation85 Posts
For a long time human believed that there is no way to break the sonic barrier and this way you couldn't travel faster as sonic speed. Personally i kinda doubt that there is something like a limit. It's hard for me to imagine that we will reach a day where can have to say "that's the limit even god wouldn't be able surpass this" same though apply to light. Of course we will have our ways of "cheating" to surpass speed of light one day.
Back to math... our math is pretty broken and it doesn't work very well, it works fantastic if you use it within it's boundaries, but if you leave them just by a dot they will epic fail. Anyway if i'm not mistaken some Dude proved something that's equivalent to "0 = 1" and the big math society is discussing about it.
Hoyle compared the random emergence of even the simplest cell to the likelihood that "a tornado sweeping through a junk-yard might assemble a Boeing 747 from the materials therein."
I believe that we are to restricted in our imagination of the definition of life. There could be 4D beings which we wouldn't be able to detect due our restriction to 3D and life don't need the same requirements as we do, especially not as we do after all we cannot even explain why we are able to "think".If we take in account that our life is nothing else as bunch of electromagnetic waves in a biological shell, then there is a pretty high chance that we are not alone.
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On March 14 2010 04:07 SpiritoftheTunA wrote:Show nested quote +On March 14 2010 04:05 Housemd wrote:
Thing is, scientists can discover all of the life galaxies they are, but they need to find us a way to get there...before time is up
I am a believer in aliens, and i think that they need the same things we need (water, sunlight and all) so this is encouraging
in my opinion science needs to find a way to get us to these "life galaxies" instead of just finding them and publishing stuff about it...which is still interesting You're talking as if the same group of scientists are responsible for finding life and improving transportation. What? The two issues are completely different, and the fact that these scientists found some life-related molecules doesn't mean other scientists aren't trying to develop transportation. EDIT: And as a matter of personal opinion, getting living humans to the closest solar system, let alone a life-sustaining galaxy, seems pretty impossible. Relativistic effects help you on the front of time, but it also makes the entire universe extremely hazardous. EDIT2: Also, science doesn't work like some sort of game where you can click "research intergalactic transportation" and have it up and running in x years. Much of the field, especially the "cutting-edge" is dependent on complete chance: without theoretical knowledge, nothing effective can be engineered. Without observation, testing, and data, no theoretical models can be made. Two hundred years ago, "chemistry" was still glorified alchemy without knowledge of discrete energy states, the existence of electrons, etc etc. What makes you think human knowledge isn't on the complete whims of chance? (sorry, "science needs to find a way to X instead of Y" just really makes me rage, especially when Y involves a lot more actual science than X)
Hey dont get on my back, im thirteen, and dont have a clue about chemistry, just stating my opinion
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On March 14 2010 06:32 Maenander wrote:@L I believe the methane found in the Mars-atmosphere last year is a strong indication that methane is not the best indicator for life on a planet, although many Mars-enthusiasts might disagree
Well, that assumes that there's no life on mars. Given the recent discovery of shallow water deposits on the moon its quite possible that the methane content is created by subsoil organisms.
So you can't really rule it out just yet.
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sweet, now we just gotta wait a billion years until these life enabling molecules evolve into sentient beings.
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The universe is infinitely large.
The chance for life to develop is extremely small.
Only seems logical that there is life somewhere else. I doubt we will ever come into contact with it without some kind of warp travel or teleportation, which might take longer than the life of our sun to discover, or maybe we will have it in a couple hundred years... who knows (I highly doubt it).
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potentially life-building molecules
keyword here is potential...
every kid got told he had potential as a kid. not everybody turned out great
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United States24670 Posts
On March 14 2010 08:22 Housemd wrote:Show nested quote +On March 14 2010 04:07 SpiritoftheTunA wrote:On March 14 2010 04:05 Housemd wrote:
Thing is, scientists can discover all of the life galaxies they are, but they need to find us a way to get there...before time is up
I am a believer in aliens, and i think that they need the same things we need (water, sunlight and all) so this is encouraging
in my opinion science needs to find a way to get us to these "life galaxies" instead of just finding them and publishing stuff about it...which is still interesting You're talking as if the same group of scientists are responsible for finding life and improving transportation. What? The two issues are completely different, and the fact that these scientists found some life-related molecules doesn't mean other scientists aren't trying to develop transportation. EDIT: And as a matter of personal opinion, getting living humans to the closest solar system, let alone a life-sustaining galaxy, seems pretty impossible. Relativistic effects help you on the front of time, but it also makes the entire universe extremely hazardous. EDIT2: Also, science doesn't work like some sort of game where you can click "research intergalactic transportation" and have it up and running in x years. Much of the field, especially the "cutting-edge" is dependent on complete chance: without theoretical knowledge, nothing effective can be engineered. Without observation, testing, and data, no theoretical models can be made. Two hundred years ago, "chemistry" was still glorified alchemy without knowledge of discrete energy states, the existence of electrons, etc etc. What makes you think human knowledge isn't on the complete whims of chance? (sorry, "science needs to find a way to X instead of Y" just really makes me rage, especially when Y involves a lot more actual science than X) Hey dont get on my back, im thirteen, and dont have a clue about chemistry, just stating my opinion
If you're opinion doesn't make sense, then the fact that you are 13 and don't have a clue about the topic doesn't mean that people who know what they are talking about (such as tuna) aren't going to try to explain to you why your opinion doesn't make sense. Don't hide behind 'OPINION' or anything... I suggest you go back through his post again and try to understand what point he was making even if he could have possibly been a bit more delicate about it.
Besides, even if we can't GET to aliens, just communicating with them would be huge. Imagine sharing 'textbooks' or god knows what else
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i have no doubt that there exist various forms of primitive life out there, aka microbes and stuff like that. the question though is if there is intelligent life out there, aka at least like reptiles or mammals on earth...
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United States241 Posts
On March 14 2010 03:47 konadora wrote:
But does having all the necessary elements -> life? I'm pretty shitty at chemistry but my thinking is that having the 'materials' there doesn't necessary mean the end products will exist.
those are some of the 'materials'
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You have to remember that the Orion Nebula is many many light years away. So for all we know life is already there.
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Methane can be found in many, many places that undoubtedly do not harbor any life as we know it (comets, anyone?). It's the simplest molecule you can form with carbon and hydrogen: its mere presence says nothing about the existence of life.
And yes, the title is wrong.
As for the existence of life elsewhere in the universe, we have three bits of information: The universe is very very large. We have found no life anywhere in the universe, except... there is life on Earth. Conclusion: probability of life is >0, but close to 0. Not sufficient to conclude that there is life elsewhere, or that there isn't life elsewhere.
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On March 14 2010 08:56 Wr3k wrote:
The universe is infinitely large.
The chance for life to develop is extremely small.
Only seems logical that there is life somewhere else. I doubt we will ever come into contact with it without some kind of warp travel or teleportation, which might take longer than the life of our sun to discover, or maybe we will have it in a couple hundred years... who knows (I highly doubt it).
I assume by infinitely you mean 'large' but finite. Also i dont like the argument "small chance, large sample size, sure thing". I supspect most people have no clue of any concrete scales(neither do i altough i study physics for 5 years now and heard courses on protein physics) and just assume the one balances the other somehow.
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Hopefully we are alone.
We can know almost definitively that we are the only intelligent life in our galaxy just from the fact that we haven't observed any signs of intelligent extra-terrestrials. We are younger than the average age of planets in the galaxy so if other advanced civilizations had evolved we would be able to detect them. The absence of aliens could be for any number of reasons:
1. Earth-like or otherwise life-sustaining conditions could be rare.
2. It could, for some reason, be very unlikely that life will actually come to exist on potentially life-sustaining planets.
3. It could, for some reason, be very unlikely that basic single-cell life forms will evolve into intelligent life.
4. Every intelligent species in the galaxy that has come before us went extinct before it could become space-faring.
It has to be one of those, and for every one that we rule out, 4 becomes the more likely answer.
If we were to find microbes on Mars then that would pretty much rule out 1 and 2. That means either it's almost impossible for microbes to evolve into intelligent life or there have been many intelligent species before us and they all went extinct before they could colonize space.
Why would we be able to escape the fate of every sentient species before us? If we are not alone, then chances are we will die off before we can colonize space.
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imagine if an intelligent species evolved elsewhere in the universe. created a game just like starcraft, had the internet just like us, and had a community dedicated to their game just like team liquid. and on the forums of this site, there was a thread about their species' scientists discovering 'life' on a region containing earth there would also have been a post just like lysdexia's in this thread, also concluding that #4 was the most likely option.
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Stop looking for life on other galaxies goddamned! The Zerg are totally hiding somewhere and you guys totally don't wanna know where that is.
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On March 14 2010 04:37 L wrote:
1) That 'pull back light' post is hilarious.
2) Scientists have been pretending that finding methane in any atmosphere is a sure sign of life because they don't believe that methane can be produced without being degraded without life.
Once you learn how extrapolation and assumption heavy astrobiology is you kinda get a distaste for the entire thing. That said, as instrumentation gets better and we get more planetary samples for analysis things will shape up considerably.
Where are you getting that methane comment?
I've been reading a lot about Titan recently (methane is ~1.4% of the atmosphere, which makes it a pretty significant component) and geological sources are mostly what are discussed. Biogenic methane is only a 'what if' scenario in that context.
What is your background in astrobiology? What is your background in any science for that matter?
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On March 14 2010 11:15 nebffa wrote:
imagine if an intelligent species evolved elsewhere in the universe. created a game just like starcraft, had the internet just like us, and had a community dedicated to their game just like team liquid. and on the forums of this site, there was a thread about their species' scientists discovering 'life' on a region containing earth there would also have been a post just like lysdexia's in this thread, also concluding that #4 was the most likely option.
I can accept multiple-life-bearing-universe theory, but the probability of that happening sounds like more on the realm of parallel universe and quantum physics. I mean, it's like that age old argument that million monkeys typing keyboard randomly will one day end up replicating Shakespeare work, disregarding all the logistic difficulties that would obviously follow.
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On March 14 2010 11:58 Freyr wrote:Show nested quote +On March 14 2010 04:37 L wrote:
1) That 'pull back light' post is hilarious.
2) Scientists have been pretending that finding methane in any atmosphere is a sure sign of life because they don't believe that methane can be produced without being degraded without life.
Once you learn how extrapolation and assumption heavy astrobiology is you kinda get a distaste for the entire thing. That said, as instrumentation gets better and we get more planetary samples for analysis things will shape up considerably. Where are you getting that methane comment?
In an oxidizing atmosphere like that of Mars or Earth methane vanishes pretty quickly, if not continously replenished. Titan's atmosphere on the other hand is reducing, so methane molecules can live like forever. It really depends on the chemistry of the planet.
If you find both methane AND oxygen in a planet's atmosphere, that planet's chemistry is quite strange, because normally those couldn't coexist in an equilibrium. Your best bet might be life. Or maybe not in the case of Mars
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On March 14 2010 05:46 Slow Motion wrote:
I think we should launch a preemptive nuke. It should reach by the time intelligent multicellular life develops.
So that's how the dinosaurs died...
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On March 14 2010 12:25 Maenander wrote:Show nested quote +On March 14 2010 11:58 Freyr wrote:On March 14 2010 04:37 L wrote:
1) That 'pull back light' post is hilarious.
2) Scientists have been pretending that finding methane in any atmosphere is a sure sign of life because they don't believe that methane can be produced without being degraded without life.
Once you learn how extrapolation and assumption heavy astrobiology is you kinda get a distaste for the entire thing. That said, as instrumentation gets better and we get more planetary samples for analysis things will shape up considerably. Where are you getting that methane comment? In an oxidizing atmosphere like that of Mars or Earth methane vanishes pretty quickly, if not continously replenished. Titan's atmosphere on the other hand is reducing, so methane molecules can live like forever. It really depends on the chemistry of the planet. If you find both methane AND oxygen in a planet's atmosphere, that planet's chemistry is quite strange, because normally those couldn't coexist in an equilibrium. Your best bet might be life. Or maybe not in the case of Mars
I understand that this is the case, but it is irrelevant in the context of the post to which I was responding, which made no attempt to qualify the statement in question.
I haven't seen any claims anywhere that methane is absolutely a sign of biological activity - only speculation that some methane may be biogenic. Speculation, so long as it's qualified, is perfectly acceptable.
Also - as far as organics go methane can exist for quite a long time even in Earth's atmosphere. I don't think anyone has claimed that exobiological activity is the most likely source of methane on any body in our solar system.
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even thinking about life in another galaxy makes my head explode
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space travel is a joke...dont expect anything close to it until 200 years so who cares
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On March 14 2010 13:40 r4j2ill wrote:
space travel is a joke...dont expect anything close to it until 200 years so who cares
[1960s]Handheld, portable phones are a joke and "personal" computers are a joke... don't expect anything close to it until 200 years, so who cares[/1960s]
See what I did there? The corollary is that they expected us to have flying cars by now, so optimism can be just as fantastically speculative as your statement is.
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cool discovery, but I really love the fact that we can find shit like this in an entire different GALAXY yet we've only explored something like 50% of our own planets oceans.
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On March 14 2010 13:56 VorcePA wrote:Show nested quote +On March 14 2010 13:40 r4j2ill wrote:
space travel is a joke...dont expect anything close to it until 200 years so who cares [1960s]Handheld, portable phones are a joke and "personal" computers are a joke... don't expect anything close to it until 200 years, so who cares[/1960s] See what I did there? The corollary is that they expected us to have flying cars by now, so optimism can be just as fantastically speculative as your statement is.
Also, weren't we already traveling in space by the end of the 60s?
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On March 14 2010 10:34 aqui wrote:Show nested quote +On March 14 2010 08:56 Wr3k wrote:
The universe is infinitely large.
The chance for life to develop is extremely small.
Only seems logical that there is life somewhere else. I doubt we will ever come into contact with it without some kind of warp travel or teleportation, which might take longer than the life of our sun to discover, or maybe we will have it in a couple hundred years... who knows (I highly doubt it). I assume by infinitely you mean 'large' but finite. Also i dont like the argument "small chance, large sample size, sure thing". I supspect most people have no clue of any concrete scales(neither do i altough i study physics for 5 years now and heard courses on protein physics) and just assume the one balances the other somehow.
For all intents and purposes it might as well be infinite. I doubt that anyone will ever know if our universe is finite. Something of such size cannot even be observed. Every time we point a space telescope into a dark corner we discover 100's galaxies with hundreds of billions of solar systems in each one. It seems kinda ridiculous, maybe even presumptuous to think that earth is that unique when we are talking about observable galaxies numbering in the hundreds of billions. Consider that each of these has hundreds of billions of stars, and that these hundreds of billions of galaxies are just the ones we can observe, and what you have is something that for all intensive purposes is so fucking huge that if the odds of life occurring in a solar system is 1 in a trillion or quadrillion even you would be foolish to think that its not possible if not probable that somewhere a planet has a form of life on it.
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On March 14 2010 14:56 Wr3k wrote:
For all intensive purposes it might as well be infinite.
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On March 14 2010 13:58 Freyr wrote:Show nested quote +On March 14 2010 13:56 VorcePA wrote:On March 14 2010 13:40 r4j2ill wrote:
space travel is a joke...dont expect anything close to it until 200 years so who cares [1960s]Handheld, portable phones are a joke and "personal" computers are a joke... don't expect anything close to it until 200 years, so who cares[/1960s] See what I did there? The corollary is that they expected us to have flying cars by now, so optimism can be just as fantastically speculative as your statement is. Also, weren't we already traveling in space by the end of the 60s?
On the topic of not looking forward to space travel in 200 years. I'm looking forward to nano-technology making me live for 200 years longer than I am supposed to sometime in the next 50 years
Seriously though... whats the point of space travel when even if you figure out how to go the speed of light it takes fucking forever to get anywhere, and then the whole theory of relativity fucks you in the ass anyways.
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While abiogenesis may occur in extraterrestrial systems, it is very unlikely that they are assembled an any way which resembles Earth's organisms. All of Earth's organisms evolved from a common ancestor, and this ancestor is the result of some random result which is essentially impossible to replicate, and unfathomably unlikely to even create remote similarities through particle interactions.
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On March 14 2010 15:04 Wr3k wrote:Show nested quote +On March 14 2010 13:58 Freyr wrote:On March 14 2010 13:56 VorcePA wrote:On March 14 2010 13:40 r4j2ill wrote:
space travel is a joke...dont expect anything close to it until 200 years so who cares [1960s]Handheld, portable phones are a joke and "personal" computers are a joke... don't expect anything close to it until 200 years, so who cares[/1960s] See what I did there? The corollary is that they expected us to have flying cars by now, so optimism can be just as fantastically speculative as your statement is. Also, weren't we already traveling in space by the end of the 60s? On the topic of not looking forward to space travel in 200 years. I'm looking forward to nano-technology making me live for 200 years longer than I am supposed to sometime in the next 50 years Seriously though... whats the point of space travel when even if you figure out how to go the speed of light it takes fucking forever to get anywhere, and then the whole theory of relativity fucks you in the ass anyways.
Remember that time dilation would mean the trips wouldn't necessarily be prohibitively long for you (though many years would pass on Earth).
Also, there is enough that we just don't know about physics such that there is no reason to imagine that we won't be able to find a workaround for the distance issue. Sorry for tired English.
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This is gonna nourish theories on alien life that came from Orion to build civilization on Earth.
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"All of Earth's organisms evolved from a common ancestor, and this ancestor is the result of some random result which is essentially impossible to replicate, and unfathomably unlikely to even create remote similarities through particle interactions."
wowowo this is just theory my friend, we have no evidences to back up that. We have no fossil records that even prove that we come from Apes. It is just assumption. Genetic records only show the similarities. That doesn't explain When, How and Why life came to be.
Do not forget that scientific theories can only be approved if it has been observed in nature or in experiments. We never witnessed a specie that turn into an other one. That is so far, science fiction.
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Sorry but human colonization of other stars is a LONG way off. The kind you might be thinking of (like star trek) will probably NEVER happen. Time dilation will help, but it's not the only obstacle. Getting a starship up to near light speed is not a piece of cake. If you want time dilation factor of 10 (so a 10 ly voyage takes 1 year) you need to get your ship to around .95c which is a lot of energy. Even at those speeds it will take a long time to get there since you need to spend a lot of time accelerating and decelerating. Plus traveling at those speeds presents its own challenges, you need shielding - even bits of dust will leave craters in most materials. And you'll need colonization supplies, life support, etc. If humans are still similar to how we are now they will be way too fragile to really pull this off. It's like playing football with an egg; you'll almost certainly break the egg unless you put a shitload of stuff to protect it.
I think the only way we'll ever colonize space is with robotic probes. You can send thousands of them, because most of them WILL get destroyed, and thousands of years is not a problem for them. If something goes wrong on the way (planet gets hit by an asteroid while ship is traveling) there isn't a bunch of colonists stuck there. And they'll be able to withstand acceleration forces far greater than people, won't suffer from cabin fever, and can handle harsher environments. They could bring along fertilized eggs so that after the robots make the planet inhabitable, it could be populated with people. But the real work will be done by robots, and filling the planet with humans is just like a bonus round. To be honest, I wouldn't be surprised if humans never ended up leaving the solar system.
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Anyone who believes in the theory of evolution would have to be a complete retard to think that no where in the ENTIRE universe (Other universes?) is there intelligent life other than earth. Of course not everyone believes in in the theory of evolution. . .I'm just saying that there are those people out there that do and think we're the only smart living things.
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On March 14 2010 16:28 starfries wrote:
Sorry but human colonization of other stars is a LONG way off. The kind you might be thinking of (like star trek) will probably NEVER happen. Time dilation will help, but it's not the only obstacle. Getting a starship up to near light speed is not a piece of cake. If you want time dilation factor of 10 (so a 10 ly voyage takes 1 year) you need to get your ship to around .95c which is a lot of energy. Even at those speeds it will take a long time to get there since you need to spend a lot of time accelerating and decelerating. Plus traveling at those speeds presents its own challenges, you need shielding - even bits of dust will leave craters in most materials. And you'll need colonization supplies, life support, etc. If humans are still similar to how we are now they will be way too fragile to really pull this off. It's like playing football with an egg; you'll almost certainly break the egg unless you put a shitload of stuff to protect it.
I think the only way we'll ever colonize space is with robotic probes. You can send thousands of them, because most of them WILL get destroyed, and thousands of years is not a problem for them. If something goes wrong on the way (planet gets hit by an asteroid while ship is traveling) there isn't a bunch of colonists stuck there. And they'll be able to withstand acceleration forces far greater than people, won't suffer from cabin fever, and can handle harsher environments. They could bring along fertilized eggs so that after the robots make the planet inhabitable, it could be populated with people. But the real work will be done by robots, and filling the planet with humans is just like a bonus round. To be honest, I wouldn't be surprised if humans never ended up leaving the solar system.
How does one colonize a star itself?
Dyson sphere? Land on the surface and tell it to quiet down?
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Theres got to be other life out there but I reckon that theres a chance (near to impossible) that we're simply the most intelligent out there....cause someones gotta be
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On March 14 2010 04:35 SpiritoftheTunA wrote:Show nested quote +On March 14 2010 04:29 LuCky. wrote:
The only way to travel farther than our solar system is through time travel. Therefore, we need the technology to "grab" light and pull it back. The speed of light is what limits our ability of time-travelling. That's not true either. Stop making things up. I'll go statement by statement. "The only way to travel farther than our solar system is through time travel." First off, the nearest star other than the sun is 4.24 light years away. That means if you travelled at 99% the speed of light, it wouldn't take that long. DEBUNKED. I'll go on though. Even if something were 150 light years away, if you traveled at a sufficient speed, time dilation (http://en.wikipedia.org/wiki/Time_dilation) would make it so time goes slower in your reference frame, so you could pull it off in 80 years if you're fast enough. "Therefore, we need the technology to "grab" light and pull it back." You mean like a black hole? What are you talking about? The speed of light is the same constant in all reference frames, you can't change a fundamental constant of the universe with something inside the universe. DEBUNKED. "The speed of light is what limits our ability of time-travelling." Okay so if the speed of light were faster, then it would still be the fastest possible speed. The speed of light is a fundamental constant that's a property of the universe, and one important property of that speed is that nothing can travel faster. (except the spacetime fabric itself and entanglement-related information, apparently) Where did you learn all this? I'm interested to hear what you think of as a credible source.
Tell me, then. What can travel at 99% the speed of light within our planet? And where are you getting your own statistics from anyways? 80 years... did you calculate it using Google?
"You mean like a black hole? What are you talking about? The speed of light is the same constant in all reference frames, you can't change a fundamental constant of the universe with something inside the universe"
That is why we cannot travel farther than our solar system yet.
The second paragraph is just you paraphrasing your first statement.
As for where I got my supposed bullshit from, the same Wikipedia article you did ^_^
Quoted from Wikipedia:
"However, more speculative approaches to interstellar travel offer the possibility of circumventing these difficulties. Special relativity offers the possibility of shortening the travel time: if a starship with sufficiently advanced engines could reach velocities approaching the speed of light, relativistic time dilation would make the voyage much shorter for the traveler. However, it would still take many years of elapsed time as viewed by the people remaining on Earth, and upon returning to Earth, the travelers would find that far more time had elapsed on Earth than had for them. (For more on this effect, see twin paradox.)"
Cool, looks like copy and paste does wonders. While we're talking about copy and pasting shit from Wikipedia, Oh, look, a proposed method of traveling faster than the speed of light without violating aforementioned "fundamental constants," which I would love to debate per subject of actuality placed with reality.
"General relativity offers the theoretical possibility that faster than light travel may be possible without violating fundamental laws of physics, for example, through wormholes, although it is still debated whether this is possible, in part, because of causality concerns. Proposed mechanisms for faster than light travel within the theory of General Relativity require the existence of exotic matter."
Maybe next time you should actually cite your sources. Thanks, Wikipedia.
And why is my title so misleading, you say? Pardon me for the linguistic faux-pas, but saying life-enabling molecules were discovered on the Orion Nebula, as versus what I have currently, would not really be that interesting of a title.
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On March 14 2010 03:57 Zurles wrote:
when can we live on the moon damn it!
it's quite hard, because the moon has lower gravity than the earth. Therefore, something must be done about bone and muscle deterioration. :/
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Could someone please edit the title of this thread to take out the galaxy part? This is most certainly not in another galaxy, and 10 minutes on wikipedia will explain why reading that kind of thing is libel to cause brain hemorrhaging.
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On March 14 2010 13:15 Freyr wrote:Show nested quote +On March 14 2010 12:25 Maenander wrote:On March 14 2010 11:58 Freyr wrote:On March 14 2010 04:37 L wrote:
1) That 'pull back light' post is hilarious.
2) Scientists have been pretending that finding methane in any atmosphere is a sure sign of life because they don't believe that methane can be produced without being degraded without life.
Once you learn how extrapolation and assumption heavy astrobiology is you kinda get a distaste for the entire thing. That said, as instrumentation gets better and we get more planetary samples for analysis things will shape up considerably. Where are you getting that methane comment? In an oxidizing atmosphere like that of Mars or Earth methane vanishes pretty quickly, if not continously replenished. Titan's atmosphere on the other hand is reducing, so methane molecules can live like forever. It really depends on the chemistry of the planet. If you find both methane AND oxygen in a planet's atmosphere, that planet's chemistry is quite strange, because normally those couldn't coexist in an equilibrium. Your best bet might be life. Or maybe not in the case of Mars I understand that this is the case, but it is irrelevant in the context of the post to which I was responding, which made no attempt to qualify the statement in question. I haven't seen any claims anywhere that methane is absolutely a sign of biological activity - only speculation that some methane may be biogenic. Speculation, so long as it's qualified, is perfectly acceptable. Also - as far as organics go methane can exist for quite a long time even in Earth's atmosphere. I don't think anyone has claimed that exobiological activity is the most likely source of methane on any body in our solar system.
I think you are a little harsh on L here. NASA constantly promotes methane as an indicator for life on Mars and elsewhere. We all know NASA tends to be a little overexcited, for obvious reasons. Just google for methane on Mars and you will see what I mean.
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This is definite proof that Admiral Loknar, the Last Orion, is still out there. Let's mount a rescue operation!
+ Show Spoiler +Reference to Master of Orion 2 for the uninitiated. Go play it now!
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On March 14 2010 19:56 Maenander wrote:Show nested quote +On March 14 2010 13:15 Freyr wrote:On March 14 2010 12:25 Maenander wrote:On March 14 2010 11:58 Freyr wrote:On March 14 2010 04:37 L wrote:
1) That 'pull back light' post is hilarious.
2) Scientists have been pretending that finding methane in any atmosphere is a sure sign of life because they don't believe that methane can be produced without being degraded without life.
Once you learn how extrapolation and assumption heavy astrobiology is you kinda get a distaste for the entire thing. That said, as instrumentation gets better and we get more planetary samples for analysis things will shape up considerably. Where are you getting that methane comment? In an oxidizing atmosphere like that of Mars or Earth methane vanishes pretty quickly, if not continously replenished. Titan's atmosphere on the other hand is reducing, so methane molecules can live like forever. It really depends on the chemistry of the planet. If you find both methane AND oxygen in a planet's atmosphere, that planet's chemistry is quite strange, because normally those couldn't coexist in an equilibrium. Your best bet might be life. Or maybe not in the case of Mars I understand that this is the case, but it is irrelevant in the context of the post to which I was responding, which made no attempt to qualify the statement in question. I haven't seen any claims anywhere that methane is absolutely a sign of biological activity - only speculation that some methane may be biogenic. Speculation, so long as it's qualified, is perfectly acceptable. Also - as far as organics go methane can exist for quite a long time even in Earth's atmosphere. I don't think anyone has claimed that exobiological activity is the most likely source of methane on any body in our solar system. I think you are a little harsh on L here. NASA constantly promotes methane as an indicator for life on Mars and elsewhere. We all know NASA tends to be a little overexcited, for obvious reasons. Just google for methane on Mars and you will see what I mean.
Some of the headlines may be designed to sensationalize the issue but if you read the articles none of them come anywhere near actually saying that methane is a sure sign of life.
Even if NASA did say such a thing, it is only one scientific body, and this would still not warrant the original comment.
Also - I think there is an appreciable difference between the idea of NASA sensationalizing its research (which in my opinion is only done to a limited extent anyway) to generate public interest and NASA losing scientific perspective because they buy into their own sensationalism.
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On March 14 2010 04:35 SpiritoftheTunA wrote:
The speed of light is a fundamental constant that's a property of the universe, and one important property of that speed is that nothing can travel faster. (except the spacetime fabric itself and entanglement-related information, apparently)
I am by no means a scientist, but I think taking some constant out of a theory and calling it a 'property of the universe' is pretty naive. I think it's more like a constant that Einstein needed to make his theory 'work' mathematically. There is, for example, an alternative relativistic mechanics theory (or whatever one might call it) developed by Poincaré, which does not need this constant. I do think it's a lot more complex and harder to use, and I think it wasn't quite able to explain the bending of light or something, so Einstein's theory is better. But this supports my point, I think, that taking a certain scientific theory and stating that it contains or directly describes 'properties of the universe' is quite naive and incorrect.
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lol humans looking for space travel when there are still shit messed up in our own world
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On March 14 2010 23:27 r4j2ill wrote:
lol humans looking for space travel when there are still shit messed up in our own world
True dat lets cancel all research on all fields that won't benefit us in the IMMEDIATE future!!!1111
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how many of you are actually credible physicists in talking about inter galactic travel?
going to another galaxy is still a myth at this point. and life is even a bigger one.
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On March 14 2010 17:01 LuCky. wrote:Show nested quote +On March 14 2010 04:35 SpiritoftheTunA wrote:On March 14 2010 04:29 LuCky. wrote:
The only way to travel farther than our solar system is through time travel. Therefore, we need the technology to "grab" light and pull it back. The speed of light is what limits our ability of time-travelling. That's not true either. Stop making things up. I'll go statement by statement. "The only way to travel farther than our solar system is through time travel." First off, the nearest star other than the sun is 4.24 light years away. That means if you travelled at 99% the speed of light, it wouldn't take that long. DEBUNKED. I'll go on though. Even if something were 150 light years away, if you traveled at a sufficient speed, time dilation (http://en.wikipedia.org/wiki/Time_dilation) would make it so time goes slower in your reference frame, so you could pull it off in 80 years if you're fast enough. "Therefore, we need the technology to "grab" light and pull it back." You mean like a black hole? What are you talking about? The speed of light is the same constant in all reference frames, you can't change a fundamental constant of the universe with something inside the universe. DEBUNKED. "The speed of light is what limits our ability of time-travelling." Okay so if the speed of light were faster, then it would still be the fastest possible speed. The speed of light is a fundamental constant that's a property of the universe, and one important property of that speed is that nothing can travel faster. (except the spacetime fabric itself and entanglement-related information, apparently) Where did you learn all this? I'm interested to hear what you think of as a credible source. Tell me, then. What can travel at 99% the speed of light within our planet? Plenty of things, electrons do it in CRT monitors every day. Seriously though, what makes you think that TIME TRAVELING (which would require going faster than the speed of light, by your claims) is less viable than traveling at 99% the speed of light? And where are you getting your own statistics from anyways? 80 years... did you calculate it using Google?
No, I've taken 4 years of high school physics and 2 terms of physics here at Uni... I've literally derived the Lorentz transformations and time dilations, my math is valid, ask ANY FUCKING PHYSICIST ANYWHERE. Here, I'll calculate the velocity required right here.
If delta t is 80 years, and the time as viewed from earth, delta t prime, is 150 years, then you would need v = .846c aka 84.6% the speed of light
"You mean like a black hole? What are you talking about? The speed of light is the same constant in all reference frames, you can't change a fundamental constant of the universe with something inside the universe"
That is why we cannot travel farther than our solar system yet.
You don't even understand what my quote is saying, do you.
Quoted from Wikipedia: Show nested quote +"However, more speculative approaches to interstellar travel offer the possibility of circumventing these difficulties. Special relativity offers the possibility of shortening the travel time: if a starship with sufficiently advanced engines could reach velocities approaching the speed of light, relativistic time dilation would make the voyage much shorter for the traveler. However, it would still take many years of elapsed time as viewed by the people remaining on Earth, and upon returning to Earth, the travelers would find that far more time had elapsed on Earth than had for them. (For more on this effect, see twin paradox.)" Cool, looks like copy and paste does wonders. While we're talking about copy and pasting shit from Wikipedia, Oh, look, a proposed method of traveling faster than the speed of light without violating aforementioned "fundamental constants," which I would love to debate per subject of actuality placed with reality.
no actually, that quote supports exactly what i said - time dilation can shorten the time it takes to travel if you travel close enough to the speed of light, making the time for the traveler shorter.
Show nested quote +"General relativity offers the theoretical possibility that faster than light travel may be possible without violating fundamental laws of physics, for example, through wormholes, although it is still debated whether this is possible, in part, because of causality concerns. Proposed mechanisms for faster than light travel within the theory of General Relativity require the existence of exotic matter."
Oh look, proposed theoretical mechanisms. I'm talking about THEORIES WITH HARD EVIDENCE, not "possibilities." Also, the "exotic matter" mentioned would be tachyons, go ahead and read up on them if you're interested. http://en.wikipedia.org/wiki/Tachyon Particularly this line: "Despite the theoretical arguments against the existence of tachyon particles, experimental searches have been conducted to test the assumption against their existence; however, no experimental evidence for or against the existence of tachyon particles has been found." If you find one, I'll believe you. Wormholes are another theoretical construct that have no experimental backing.
LEARN PHYSICS PLEASE.
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On March 14 2010 22:57 ManBearPig wrote:Show nested quote +On March 14 2010 04:35 SpiritoftheTunA wrote:
The speed of light is a fundamental constant that's a property of the universe, and one important property of that speed is that nothing can travel faster. (except the spacetime fabric itself and entanglement-related information, apparently)
I am by no means a scientist, but I think taking some constant out of a theory and calling it a 'property of the universe' is pretty naive. I think it's more like a constant that Einstein needed to make his theory 'work' mathematically. There is, for example, an alternative relativistic mechanics theory (or whatever one might call it) developed by Poincaré, which does not need this constant. I do think it's a lot more complex and harder to use, and I think it wasn't quite able to explain the bending of light or something, so Einstein's theory is better. But this supports my point, I think, that taking a certain scientific theory and stating that it contains or directly describes 'properties of the universe' is quite naive and incorrect.
Okay, let me add the qualifier "it is supported by overwhelming scientific consensus that"
What's your point again? People try all the time to mess with fundamentally accepted theories in order to explain the yet unexplained, but if one of these modifications worked particularly well, then scientific consensus wouldn't be all up on "the speed of light is the cosmic speed limit" thing. Which it is. That's the viewpoint I'm representing. Are there people who don't believe it? Sure. Science can't really prove anything, it can only fit things really really really well, and speedoflight=fundamentalconstant=cosmicspeedlimit is one of those accepted laws that fit reality really really really well.
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United States24670 Posts
On March 15 2010 00:38 SpiritoftheTunA wrote:Show nested quote +On March 14 2010 22:57 ManBearPig wrote:On March 14 2010 04:35 SpiritoftheTunA wrote:
The speed of light is a fundamental constant that's a property of the universe, and one important property of that speed is that nothing can travel faster. (except the spacetime fabric itself and entanglement-related information, apparently)
I am by no means a scientist, but I think taking some constant out of a theory and calling it a 'property of the universe' is pretty naive. I think it's more like a constant that Einstein needed to make his theory 'work' mathematically. There is, for example, an alternative relativistic mechanics theory (or whatever one might call it) developed by Poincaré, which does not need this constant. I do think it's a lot more complex and harder to use, and I think it wasn't quite able to explain the bending of light or something, so Einstein's theory is better. But this supports my point, I think, that taking a certain scientific theory and stating that it contains or directly describes 'properties of the universe' is quite naive and incorrect. Okay, let me add the qualifier "it is supported by overwhelming scientific consensus that" What's your point again?
And c comes directly out of knowing the permittivity and permeability of space :p
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I've taken 4 years of high school physics and 2 terms of physics here at Uni
there is an expert on time travel if there ever was one
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Vatican City State2594 Posts
On March 14 2010 04:05 Housemd wrote:
Thing is, scientists can discover all of the life galaxies they are, but they need to find us a way to get there...before time is up
I am a believer in aliens, and i think that they need the same things we need (water, sunlight and all) so this is encouraging
in my opinion science needs to find a way to get us to these "life galaxies" instead of just finding them and publishing stuff about it...which is still interesting
Dude, some organisms on EARTH don't need sunlight or water to survive... How could you be so presumptuous to assume that beings from a different world will require the same things we do? I guess your alias is one explanation, but House is usually right -_-;
On March 15 2010 00:11 SkylineSC wrote:
how many of you are actually credible physicists in talking about inter galactic travel?
going to another galaxy is still a myth at this point. and life is even a bigger one.
Going to another galaxy is actually 100% possible - it'd just take incredibly long, and would have to be on a self-sustaining colony ship.
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United States24670 Posts
On March 15 2010 01:06 SkylineSC wrote:Show nested quote +I've taken 4 years of high school physics and 2 terms of physics here at Uni there is an expert on time travel if there ever was one
My degree in physics says that tuna has been pretty accurate on most of these things. If you want me to go get some post docs to register on tl let me know
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On March 15 2010 01:06 SkylineSC wrote:Show nested quote +I've taken 4 years of high school physics and 2 terms of physics here at Uni there is an expert on time travel if there ever was one
Well no, that's honesty, I don't need to take courses beyond what I have to know that time travel is highly theoretical - if there were any more evidence for the possibility, I'm sure humanity would know about it.
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This is interesting due to the fact that i having a conversation about it in class today with my math teacher.
HE says that the reason we can't travel the speed of light is due to the fact that this happens:
When we shoot a particle of light into a spectrum (or something, not quite sure) on the other end, the particle turns out to be TWO particles, each in a different location on some black paper they put as a "receiver". If we can find out what causes this, we can travel the speed of light to different galaxies.
And i think it is important to see other galaxies and matter and life...now that i think about it.
This is way over my head, so please don't criticize. T_T
Imagine if these were the protoss...battling the zerg on Aiur
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On March 15 2010 01:49 Housemd wrote:
This is interesting due to the fact that i having a conversation about it in class today with my math teacher.
HE says that the reason we can't travel the speed of light is due to the fact that this happens:
When we shoot a particle of light into a spectrum (or something, not quite sure) on the other end, the particle turns out to be TWO particles, each in a different location on some black paper they put as a "receiver". If we can find out what causes this, we can travel the speed of light to different galaxies.
I think you're talking about this. http://en.wikipedia.org/wiki/Double-slit_experiment
This is an experiment that demonstrates the wave-particle duality of light. If you shoot a photon of light through two slits, and don't detect which slit it goes through, then the photon will act as if it went through both slits (even though it technically should be only one particle) and interfered with itself (as if it were a wave). This has to do with quantum mechanics, which I highly suggest you should learn in your academic future! To be honest, it doesn't have that much to do with the speed of light itself, but it's one of the things that got me interested in physics, so by all means, be open to the subject!
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On March 15 2010 00:11 SkylineSC wrote:
how many of you are actually credible physicists in talking about inter galactic travel?
going to another galaxy is still a myth at this point. and life is even a bigger one.
Just like airplanes were in the 1500s. I find it funny that you use the word "myth".
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United States24670 Posts
On March 15 2010 01:55 Saturnize wrote:Show nested quote +On March 15 2010 00:11 SkylineSC wrote:
how many of you are actually credible physicists in talking about inter galactic travel?
going to another galaxy is still a myth at this point. and life is even a bigger one. Just like airplanes were in the 1500s.
This argument, which we hear a lot, bugs me a little bit. Just because we couldn't make airplanes in the 1500s the same we we can't make intergalactic spaceships today doesn't mean that intergalactic spaceships are as plausible as airplanes. On the other hand you don't want to rule things out since there is the possibility of being pleasantly surprised.
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I read the odds against all the exact chemicals and molecules that make up a cell, being in a pile, and randomly making a cell... being like almost impossible.
Self replicating protein chains and things like that would be really interesting, I wonder if they will every find anything like that in space. My guess would be no.
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On March 14 2010 15:02 Mindcrime wrote:Show nested quote +On March 14 2010 14:56 Wr3k wrote:
For all intensive purposes it might as well be infinite.
For all intents and purposes*
Happy?
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On March 15 2010 00:11 SkylineSC wrote:
how many of you are actually credible physicists in talking about inter galactic travel?
going to another galaxy is still a myth at this point. and life is even a bigger one.
Dude, do you actually believe that they a trillion+ stars, a trillion+ galaxies and a trillion bunch of planets in outer space and we are the only ones out there....
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HnR)hT
United States3468 Posts
On March 14 2010 22:57 ManBearPig wrote:Show nested quote +On March 14 2010 04:35 SpiritoftheTunA wrote:
The speed of light is a fundamental constant that's a property of the universe, and one important property of that speed is that nothing can travel faster. (except the spacetime fabric itself and entanglement-related information, apparently)
I am by no means a scientist, but I think taking some constant out of a theory and calling it a 'property of the universe' is pretty naive. I think it's more like a constant that Einstein needed to make his theory 'work' mathematically. There is, for example, an alternative relativistic mechanics theory (or whatever one might call it) developed by Poincaré, which does not need this constant. I do think it's a lot more complex and harder to use, and I think it wasn't quite able to explain the bending of light or something, so Einstein's theory is better. But this supports my point, I think, that taking a certain scientific theory and stating that it contains or directly describes 'properties of the universe' is quite naive and incorrect.
You are thinking about the speed of light in the wrong way. It is simply a conversion factor between the units of length that we use, which are arbitrary, and units of time. Since Einstein we know that length and time are equivalent in some sense, and it is natural to measure them in the same units. That's what is usually done in relativity, by setting the speed of light equal to one.
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On March 15 2010 02:21 Housemd wrote:Show nested quote +On March 15 2010 00:11 SkylineSC wrote:
how many of you are actually credible physicists in talking about inter galactic travel?
going to another galaxy is still a myth at this point. and life is even a bigger one. Dude, do you actually believe that they a trillion+ stars, a trillion+ galaxies and a trillion bunch of planets in outer space and we are the only ones out there....
Actually the trillion bunch of planets is already in our own galaxy, knowing the fact that we can already estimate the number of galaxies in the universe to be 500 billions. If we were really alone that would make 1 chance out of 500 billions trillions planets^^
We never really witnessed any kind of thing in the universe with such low probability rate. I mean your grandma would have more chances to live 1000 years!
So I would rather believe that life is a common thing in the universe.
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Thats pretty cool.. were deffintly not alone...
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Just a question of Einstein's theory of relativity, it states the that the universe is expanding FASTER than the speed of light.
If this is true, no matter how fast we go, we will essentially never be able to reach another body in outer space, right?
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HnR)hT
United States3468 Posts
On March 15 2010 03:09 Housemd wrote:
Just a question of Einstein's theory of relativity, it states the that the universe is expanding FASTER than the speed of light. If this is true, no matter how fast we go, we will essentially never be able to reach another body in outer space, right?
No, because cosmological recession velocities are utterly negligible for distances within our galaxy and nearby galaxies. In fact, objects that have superluminal recession velocities have distances in the gigaparsecs. So cosmology has no bearing on the possibility of interstellar, and even intergallactic travel.
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what the fuck is going on in this thread i dont even know. all the article said was that organic molecules were found on a nebula holy fuck gigaparsec the fuck?
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paulinepain, the most obvious argument is the anthropic principle: Suppose life is very, very improbable. Let's say it's so probable that we can only expect it to occur once in 10^30 planets. Then, that life that did occur could look around and say "hey, we're here, so that must mean there is life out there too."
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On March 15 2010 01:06 SkylineSC wrote:Show nested quote +I've taken 4 years of high school physics and 2 terms of physics here at Uni there is an expert on time travel if there ever was one
As a PhD student in astrophysics, I'd say that SpiritoftheTunA seems to know what he's talking about.
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misleading thread title
u_u can't wait for when we actually do discover other life (if it's in my lifetime)
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On March 15 2010 04:47 LuCky. wrote:
what the fuck is going on in this thread i dont even know. all the article said was that organic molecules were found on a nebula holy fuck gigaparsec the fuck?
Why would you take such an anti-intellectual stance just because your speculations were wrong? Science is a learning process, and that's a terrible attitude to have. Learn from your misconceptions, you shouldn't attach so much of your pride to speculative beliefs. If they're wrong, then so be it, you assumed something wrongly, life goes on. Don't pretend that tangential discussions are overreactions - what's this thread for if not discussing the article. Just because some people in this thread have more background on the subject doesn't mean you can't learn from it if you want to. Look stuff up! Wikipedia is a great resource. Don't have a preconceived notion and try to match the vocabulary in the articles to your definition - if you don't understand a part of the vocabulary, look it up! It's the best way to form an accurate perspective of physical reality.
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On March 14 2010 23:27 r4j2ill wrote:
lol humans looking for space travel when there are still shit messed up in our own world
lol paleo-indians migrating to the Americas when there is still shit messed up in Asia
lol homo sapiens looking to settle the rest of the world when there is still shit messed up in Africa
amidoinitrite?
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On March 15 2010 04:36 HnR)hT wrote:Show nested quote +On March 15 2010 03:09 Housemd wrote:
Just a question of Einstein's theory of relativity, it states the that the universe is expanding FASTER than the speed of light. If this is true, no matter how fast we go, we will essentially never be able to reach another body in outer space, right? No, because cosmological recession velocities are utterly negligible for distances within our galaxy and nearby galaxies. In fact, objects that have superluminal recession velocities have distances in the gigaparsecs. So cosmology has no bearing on the possibility of interstellar, and even intergallactic travel.
Rewording this, the rate at which the universe is expanding is most noticeable at the far ends of what we can observe, literally. Things closer to us, i.e. the orion nebula, aren't running away at any rate that could prevent us from getting to it (well at least not much more so than a static universe). If everything in the universe were expanding faster than the speed of light, as Housemd suggests, then we'd be ripped apart at the subatomic level pretty quickly. In fact, that's one of the possible death scenarios for the universe. http://en.wikipedia.org/wiki/Big_rip Oooh science
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How many people could we fit on the moon with population density equal to the US as a whole?
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On March 17 2010 03:24 Perseverance wrote:
How many people could we fit on the moon with population density equal to the US as a whole?
That's something you should be able to calculate yourself. I'll give you a formula, you look up the values.
amount of people on moon = surface area of moon * amount of people in the US / surface area of US
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United States42558 Posts
On March 17 2010 03:26 SpiritoftheTunA wrote:Show nested quote +On March 17 2010 03:24 Perseverance wrote:
How many people could we fit on the moon with population density equal to the US as a whole? That's something you should be able to calculate yourself. I'll give you a formula, you look up the values. amount of people on moon = surface area of moon * amount of people in the US / surface area of US
Why would you fit them on with an equal population density to the US? If you want them to live then no density will be thin enough because there's no water. If you don't want them to live then you could just pile them up across the entire surface several layers deep.
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Psh, it was like one in a over 9000 gazillion chances that we got life on earth with the molecules, not like theres going to be life on another planet just because we found some molecules needed for life.
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On March 17 2010 04:16 MuffinDude wrote:
Psh, it was like one in a over 9000 gazillion chances that we got life on earth with the molecules, not like theres going to be life on another planet just because we found some molecules needed for life.
I get your mathematically and scientifically-backed point.
Wait nope, lost it.
(if you're disagreeing with the title of the thread, it's been done at least twenty times already)
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On March 15 2010 01:53 SpiritoftheTunA wrote:Show nested quote +On March 15 2010 01:49 Housemd wrote:
This is interesting due to the fact that i having a conversation about it in class today with my math teacher.
HE says that the reason we can't travel the speed of light is due to the fact that this happens:
When we shoot a particle of light into a spectrum (or something, not quite sure) on the other end, the particle turns out to be TWO particles, each in a different location on some black paper they put as a "receiver". If we can find out what causes this, we can travel the speed of light to different galaxies. I think you're talking about this. http://en.wikipedia.org/wiki/Double-slit_experimentThis is an experiment that demonstrates the wave-particle duality of light. If you shoot a photon of light through two slits, and don't detect which slit it goes through, then the photon will act as if it went through both slits (even though it technically should be only one particle) and interfered with itself (as if it were a wave). This has to do with quantum mechanics, which I highly suggest you should learn in your academic future! To be honest, it doesn't have that much to do with the speed of light itself, but it's one of the things that got me interested in physics, so by all means, be open to the subject!
Is there a reason for the difference in behavior when it is observed vs unobserved?
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If it's unobserved then there is a range of places where it could be, like a probability distribution. Pretty reasonable... but the weird thing that quantum mechanics says that it doesn't just exist somewhere within the distribution, but it actually exists EVERYWHERE to some extent. It's spread out over space, just like a wave. (it's not exactly like this but its close enough) This means it can interfere with itself, etc. It doesn't just happen for light either, it works with electrons, protons.. technically it should even happen when you walk through a door but the wavelength involved is so tiny that you'll never see it.
When you observe a particle (or detect which slit it goes through), you force it to have a definite position so suddenly the probability distribution collapses down to a point. It's like flipping a coin - when it's in the air, it has probably H with 50% and probability T with 50%, but after you catch it and look at it, it's one or the other with 100% probability. Since the distribution is basically one point now, it behaves like a particle again.
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On March 17 2010 05:53 starfries wrote:
If it's unobserved then there is a range of places where it could be, like a probability distribution. Pretty reasonable... but the weird thing that quantum mechanics says that it doesn't just exist somewhere within the distribution, but it actually exists EVERYWHERE to some extent. It's spread out over space, just like a wave. (it's not exactly like this but its close enough) This means it can interfere with itself, etc. It doesn't just happen for light either, it works with electrons, protons.. technically it should even happen when you walk through a door but the wavelength involved is so tiny that you'll never see it.
When you observe a particle (or detect which slit it goes through), you force it to have a definite position so suddenly the probability distribution collapses down to a point. It's like flipping a coin - when it's in the air, it has probably H with 50% and probability T with 50%, but after you catch it and look at it, it's one or the other with 100% probability. Since the distribution is basically one point now, it behaves like a particle again.
But what if some amoeba was just eyeballing that particle the whole time and we never found out?
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On March 17 2010 06:22 spitball wrote:Show nested quote +On March 17 2010 05:53 starfries wrote:
If it's unobserved then there is a range of places where it could be, like a probability distribution. Pretty reasonable... but the weird thing that quantum mechanics says that it doesn't just exist somewhere within the distribution, but it actually exists EVERYWHERE to some extent. It's spread out over space, just like a wave. (it's not exactly like this but its close enough) This means it can interfere with itself, etc. It doesn't just happen for light either, it works with electrons, protons.. technically it should even happen when you walk through a door but the wavelength involved is so tiny that you'll never see it.
When you observe a particle (or detect which slit it goes through), you force it to have a definite position so suddenly the probability distribution collapses down to a point. It's like flipping a coin - when it's in the air, it has probably H with 50% and probability T with 50%, but after you catch it and look at it, it's one or the other with 100% probability. Since the distribution is basically one point now, it behaves like a particle again. But what if some amoeba was just eyeballing that particle the whole time and we never found out?
The short answer is:
Observation is actually not a good word for this sort of stuff, and what we really are talking about is measurement. The modern interpretation is that "measurement" is a forced decoherence of the quantum state by a macroscopic system, and an amoeba is a macroscopic system so it will cause the collapse of the wavefunction before it enters the slits. So you will see particle behaviour, as if you measured it yourself.
Ok that was actually not that short of an answer but the long answer is a LOT longer.
short short answer: the amoeba counts as an observer, it behaves as a particle
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On March 17 2010 04:28 decafchicken wrote:Show nested quote +On March 15 2010 01:53 SpiritoftheTunA wrote:On March 15 2010 01:49 Housemd wrote:
This is interesting due to the fact that i having a conversation about it in class today with my math teacher.
HE says that the reason we can't travel the speed of light is due to the fact that this happens:
When we shoot a particle of light into a spectrum (or something, not quite sure) on the other end, the particle turns out to be TWO particles, each in a different location on some black paper they put as a "receiver". If we can find out what causes this, we can travel the speed of light to different galaxies. I think you're talking about this. http://en.wikipedia.org/wiki/Double-slit_experimentThis is an experiment that demonstrates the wave-particle duality of light. If you shoot a photon of light through two slits, and don't detect which slit it goes through, then the photon will act as if it went through both slits (even though it technically should be only one particle) and interfered with itself (as if it were a wave). This has to do with quantum mechanics, which I highly suggest you should learn in your academic future! To be honest, it doesn't have that much to do with the speed of light itself, but it's one of the things that got me interested in physics, so by all means, be open to the subject! Is there a reason for the difference in behavior when it is observed vs unobserved?
Quantum mechanics is a semantic nightmare and is difficult to teach even to physics students. So I'll give you my simple input on this issue:
+ Show Spoiler [Trust me, this is simple.] +
In quantum mechanics, one of the major ways of examining systems (things doing stuff) is by using the concept of the wave function. The wave function is a complete abstraction - it is a mathematical entity that can be manipulated to get real answers to problems. Knowing how to setup a wave function for a specific system is something I won't even attempt to describe.
So why is this considered physics and not just mathematics? Well, let's say you have a system (en electron or something), and you wanna measure it (for whatever reason, physicists don't care). How do you represent that mathematically? How do you know what answer you will get when you measure?
What you do is this:
1. Figure out what quantity you're measuring.
2. Use the mathematical 'operator' associated with that quantity on the system's wavefunction.
3. The result is hopefully some constant times the wavefunction - so k*W(x,y,z,t).
In this case, the answer to "what will I get when I measure this?" is 'k'.
-----
It turns out that it's not quite this simple. Most wave functions are made of up a combination of a whole bunch of different functions. So
W = W1 + W2 + W3
What the hell does that mean? Well go back to your step-by-step process.
1. What quantity are you measuring (e.g. velocity)?
2. Use the 'velocity operator' on W.
3. The result is not quite what you were hoping for, it's
k1*W1 + k2*W2 + k3*W3
so does that mean you measure all of them(!!!!)? No - what this actually means is that you will measure one of the values k1, k2, or k3. Not all of them. You can use some tricky math to work out the probability that you will measure the individual terms, but you can never predict which one it will be.
-------
So what does that have to do with a system being observed?
Well the interpretation is that W = W1 + W2 + W3 is a system with three possible states. If you make the measurement of the system, you will measure k1 or k2 or k3 but never anything else.
What happens when you measure a system? So take the electron from earlier. We'll measure it's velocity. Let's say we get k2, and that k2 represents the electron moving off to the right at speed k2. Let's measure it again a little bit later. What do we get?
We sure as hell better get k2. If you measure something definitely happening, it better be definitely happening. So what does that mean for the wavefunction W?
Does W still equal W1 + W2 + W3? No, W = W2 because we have measured the system and know the answer. But that means we changed the wavefunction W just by measuring it. This is what is meant when people talk about observers. If there is some interaction that happens between your electron and something else, your electron most likely ends up in a definite state instead of in a probabilistic state. Observers don't have to people with eyes. Or cats. Or alive. Just something that interacts physically with the system.
/edit - Massive government-issue disclaimers for those who know about all the 'but what if...' cases I didn't talk about.
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On March 14 2010 05:46 Slow Motion wrote:
I think we should launch a preemptive nuke. It should reach by the time intelligent multicellular life develops.
the descolada!
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On March 14 2010 03:47 konadora wrote:
But does having all the necessary elements -> life? I'm pretty shitty at chemistry but my thinking is that having the 'materials' there doesn't necessary mean the end products will exist.
Yeah man, enough concentration and a little time can produce complex organic compunds. As the shit cools down, longer and more complex shit can be made.
It's like looking at our solar system a few billion years ago when all the shit was still forming.
Take formaldehyde and Hydrogen Cyanide. At high temperatures and if enough of the stuff is there the Cyanide can add to the C=O bond and make a simple amino acid.
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On March 15 2010 02:07 cUrsOr wrote:
I read the odds against all the exact chemicals and molecules that make up a cell, being in a pile, and randomly making a cell... being like almost impossible.
Self replicating protein chains and things like that would be really interesting, I wonder if they will every find anything like that in space. My guess would be no.
mRNA can self replicate.
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On March 17 2010 12:25 Rev0lution wrote:Show nested quote +On March 15 2010 02:07 cUrsOr wrote:
I read the odds against all the exact chemicals and molecules that make up a cell, being in a pile, and randomly making a cell... being like almost impossible.
Self replicating protein chains and things like that would be really interesting, I wonder if they will every find anything like that in space. My guess would be no. mRNA can self replicate.
assuming that the first life contained rna only
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HnR)hT
United States3468 Posts
On March 17 2010 09:49 DefMatrixUltra wrote:Show nested quote +On March 17 2010 04:28 decafchicken wrote:On March 15 2010 01:53 SpiritoftheTunA wrote:On March 15 2010 01:49 Housemd wrote:
This is interesting due to the fact that i having a conversation about it in class today with my math teacher.
HE says that the reason we can't travel the speed of light is due to the fact that this happens:
When we shoot a particle of light into a spectrum (or something, not quite sure) on the other end, the particle turns out to be TWO particles, each in a different location on some black paper they put as a "receiver". If we can find out what causes this, we can travel the speed of light to different galaxies. I think you're talking about this. http://en.wikipedia.org/wiki/Double-slit_experimentThis is an experiment that demonstrates the wave-particle duality of light. If you shoot a photon of light through two slits, and don't detect which slit it goes through, then the photon will act as if it went through both slits (even though it technically should be only one particle) and interfered with itself (as if it were a wave). This has to do with quantum mechanics, which I highly suggest you should learn in your academic future! To be honest, it doesn't have that much to do with the speed of light itself, but it's one of the things that got me interested in physics, so by all means, be open to the subject! Is there a reason for the difference in behavior when it is observed vs unobserved? Quantum mechanics is a semantic nightmare and is difficult to teach even to physics students. So I'll give you my simple input on this issue: + Show Spoiler [Trust me, this is simple.] +
In quantum mechanics, one of the major ways of examining systems (things doing stuff) is by using the concept of the wave function. The wave function is a complete abstraction - it is a mathematical entity that can be manipulated to get real answers to problems. Knowing how to setup a wave function for a specific system is something I won't even attempt to describe.
So why is this considered physics and not just mathematics? Well, let's say you have a system (en electron or something), and you wanna measure it (for whatever reason, physicists don't care). How do you represent that mathematically? How do you know what answer you will get when you measure?
What you do is this:
1. Figure out what quantity you're measuring.
2. Use the mathematical 'operator' associated with that quantity on the system's wavefunction.
3. The result is hopefully some constant times the wavefunction - so k*W(x,y,z,t).
In this case, the answer to "what will I get when I measure this?" is 'k'.
-----
It turns out that it's not quite this simple. Most wave functions are made of up a combination of a whole bunch of different functions. So
W = W1 + W2 + W3
What the hell does that mean? Well go back to your step-by-step process.
1. What quantity are you measuring (e.g. velocity)?
2. Use the 'velocity operator' on W.
3. The result is not quite what you were hoping for, it's
k1*W1 + k2*W2 + k3*W3
so does that mean you measure all of them(!!!!)? No - what this actually means is that you will measure one of the values k1, k2, or k3. Not all of them. You can use some tricky math to work out the probability that you will measure the individual terms, but you can never predict which one it will be.
-------
So what does that have to do with a system being observed?
Well the interpretation is that W = W1 + W2 + W3 is a system with three possible states. If you make the measurement of the system, you will measure k1 or k2 or k3 but never anything else.
What happens when you measure a system? So take the electron from earlier. We'll measure it's velocity. Let's say we get k2, and that k2 represents the electron moving off to the right at speed k2. Let's measure it again a little bit later. What do we get?
We sure as hell better get k2. If you measure something definitely happening, it better be definitely happening. So what does that mean for the wavefunction W?
Does W still equal W1 + W2 + W3? No, W = W2 because we have measured the system and know the answer. But that means we changed the wavefunction W just by measuring it. This is what is meant when people talk about observers. If there is some interaction that happens between your electron and something else, your electron most likely ends up in a definite state instead of in a probabilistic state. Observers don't have to people with eyes. Or cats. Or alive. Just something that interacts physically with the system.
/edit - Massive government-issue disclaimers for those who know about all the 'but what if...' cases I didn't talk about.
I would put it differently. It's not that quantum mechanics is difficult to teach to physics students; it's that it is not well understood by anyone at all. That's why all these perverse, practically-no-chance-of-being-right "interpretations" (many worlds, consciousness-causes-collapse, etc.) are floating around and being debated by philosophers who think about quantum mechanics for a living. Perhaps in this century someone will manage to explain the math rationally, to everyone's satisfaction...
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On March 18 2010 05:41 HnR)hT wrote:Show nested quote +On March 17 2010 09:49 DefMatrixUltra wrote:On March 17 2010 04:28 decafchicken wrote:On March 15 2010 01:53 SpiritoftheTunA wrote:On March 15 2010 01:49 Housemd wrote:
This is interesting due to the fact that i having a conversation about it in class today with my math teacher.
HE says that the reason we can't travel the speed of light is due to the fact that this happens:
When we shoot a particle of light into a spectrum (or something, not quite sure) on the other end, the particle turns out to be TWO particles, each in a different location on some black paper they put as a "receiver". If we can find out what causes this, we can travel the speed of light to different galaxies. I think you're talking about this. http://en.wikipedia.org/wiki/Double-slit_experimentThis is an experiment that demonstrates the wave-particle duality of light. If you shoot a photon of light through two slits, and don't detect which slit it goes through, then the photon will act as if it went through both slits (even though it technically should be only one particle) and interfered with itself (as if it were a wave). This has to do with quantum mechanics, which I highly suggest you should learn in your academic future! To be honest, it doesn't have that much to do with the speed of light itself, but it's one of the things that got me interested in physics, so by all means, be open to the subject! Is there a reason for the difference in behavior when it is observed vs unobserved? Quantum mechanics is a semantic nightmare and is difficult to teach even to physics students. So I'll give you my simple input on this issue: + Show Spoiler [Trust me, this is simple.] +
In quantum mechanics, one of the major ways of examining systems (things doing stuff) is by using the concept of the wave function. The wave function is a complete abstraction - it is a mathematical entity that can be manipulated to get real answers to problems. Knowing how to setup a wave function for a specific system is something I won't even attempt to describe.
So why is this considered physics and not just mathematics? Well, let's say you have a system (en electron or something), and you wanna measure it (for whatever reason, physicists don't care). How do you represent that mathematically? How do you know what answer you will get when you measure?
What you do is this:
1. Figure out what quantity you're measuring.
2. Use the mathematical 'operator' associated with that quantity on the system's wavefunction.
3. The result is hopefully some constant times the wavefunction - so k*W(x,y,z,t).
In this case, the answer to "what will I get when I measure this?" is 'k'.
-----
It turns out that it's not quite this simple. Most wave functions are made of up a combination of a whole bunch of different functions. So
W = W1 + W2 + W3
What the hell does that mean? Well go back to your step-by-step process.
1. What quantity are you measuring (e.g. velocity)?
2. Use the 'velocity operator' on W.
3. The result is not quite what you were hoping for, it's
k1*W1 + k2*W2 + k3*W3
so does that mean you measure all of them(!!!!)? No - what this actually means is that you will measure one of the values k1, k2, or k3. Not all of them. You can use some tricky math to work out the probability that you will measure the individual terms, but you can never predict which one it will be.
-------
So what does that have to do with a system being observed?
Well the interpretation is that W = W1 + W2 + W3 is a system with three possible states. If you make the measurement of the system, you will measure k1 or k2 or k3 but never anything else.
What happens when you measure a system? So take the electron from earlier. We'll measure it's velocity. Let's say we get k2, and that k2 represents the electron moving off to the right at speed k2. Let's measure it again a little bit later. What do we get?
We sure as hell better get k2. If you measure something definitely happening, it better be definitely happening. So what does that mean for the wavefunction W?
Does W still equal W1 + W2 + W3? No, W = W2 because we have measured the system and know the answer. But that means we changed the wavefunction W just by measuring it. This is what is meant when people talk about observers. If there is some interaction that happens between your electron and something else, your electron most likely ends up in a definite state instead of in a probabilistic state. Observers don't have to people with eyes. Or cats. Or alive. Just something that interacts physically with the system.
/edit - Massive government-issue disclaimers for those who know about all the 'but what if...' cases I didn't talk about. I would put it differently. It's not that quantum mechanics is difficult to teach to physics students; it's that it is not well understood by anyone at all. That's why all these perverse, practically-no-chance-of-being-right "interpretations" (many worlds, consciousness-causes-collapse, etc.) are floating around and being debated by philosophers who think about quantum mechanics for a living. Perhaps in this century someone will manage to explain the math rationally, to everyone's satisfaction...
Yes, part of the reason is that it openly tells you that things work in ways which humans aren't used to. The issue with quantum mechanics is that it's the realm of physics where instead of using your 'real' intuition, you have to use your 'mathematical' intuition in order to gain insight into problems.
From a semantical point of view, trying to describe something happening quantum mechanically is nightmarish. When talking about quantum mechanics to the general public (or even, like you say, in a philosophical sense), it's pretty much guaranteed that
a) You will not get your point across.
b) You will dig a semantic grave for yourself.
c) You will leave those interested mystified.
That's why I tried to bring some of the math in. It's the mathematical concepts which are key to 'understanding' quantum mechanics. Understanding it in a semantical sense just seems almost impossible.
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EPT![[image loading]](http://ipac.jpl.nasa.gov/media_images/ssc2008-10b_medium.jpg)
![[image loading]](http://upload.wikimedia.org/math/8/e/8/8e8943fcbf5e131710d8d04571f428e5.png)
