|
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.
|
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.
|
lol humans looking for space travel when there are still shit messed up in our own world
|
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
|
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.
|
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.
|
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.
|
United States24669 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
|
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
|
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.
|
United States24669 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
|
|
|
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.
|
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
|
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!
|
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".
|
United States24669 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.
|
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.
|
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?
|
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....
|
|
|
|
|
|
EPT![[image loading]](http://upload.wikimedia.org/math/8/e/8/8e8943fcbf5e131710d8d04571f428e5.png)
