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On May 01 2012 02:29 summerloud wrote:Show nested quote +On May 01 2012 02:05 TheFish7 wrote:
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I'm a big believer that we are going to find lots and lots of life out there. We have found life in some of the most inhospitable regions of earth without a clue to how it got there. Intelligent life may me another matter though - most animals we know of don't actually need to evolve a big brain to survive.
the thing most people dont realize is: life evolving to be able to survive in extreme habitats does not equal life being able to form in these conditions. its really a moot point in a way because, like i said before, there is just no good theory of how life ever came into existence in the first place, but it might require a very very specific set of environment and/or a fucking miracle i have to say the more i studied biology and found out how extremely complicated the most primitive living cell is the more i began to believe in purpose/teleology/a creator right now it seems fashionable in biology to have the model that self-catalysing proteins where the first stage of life, followed by rna-based life, followed by dna-based life. how evolution is supposed to be able to change the very thing it needs to work (the genetic code), nobody has been able to explain to me. to me it seems impossible for life to switch from rna to dna without admitting that there is a purpose driving the whole of evolution. blind watch maker my ass... (i despise dawkins btw) i could rave on and on about this topic for pages i guess, but im not sure if this is the right thread for it... ill wait for the next evolution vs intelligent design thread to pop up i guess 
There's been a lot of theory on how life evolved. People made primordial soup experiments and showed that RNA precursors can be generated by pure physical processes. Other groups have even shown how an RNA molecule can act as an evolving, self-catalyzing molecule. Please read up on scientific literature before spreading myths.
RNA is believed to be the very first self-replicating molecule. Ever heard of ribozymes? The RNA world is only feasible in a reducing environment free of molecular oxygen. Proteins came later in the equation. If you put proteins first, you've got yourself a chicken and egg scenario.
RNA has advantages over DNA: higher rates of mutation. The higher rate of mutation is good during the early stages of RNA evolution. However, once RNA molecules predominated, it was an evolutionary advantage to preserve a "good" sequence, which allowed the switch from RNA to DNA. However, RNA is not completely eliminated as DNA isn't flexible enough to perform certain functions of RNA.
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On May 01 2012 00:44 ChosenSC2 wrote:
It doesn't matter cuz we'll never be able to get there? Especially in any sort of mass travel form ^^
You can get there.
Relativity doesn't actually prevent you from travelling anywhere in a reasonable amount of time, because as you speed up the universe appears to shrink. At 1/sqrt(2) * c m/s you're effectively travelling at the speed of light, if you measure time in the traveller's reference frame and distance in the rest frame of your departure point. You could travel to Alpha Centauri and only age a few years, but people back on Earth would've aged millions of years.
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Doesn't matter will take us 10000000000000000 years to get there because no one can figure out how to travel faster, in such high speed that it takes a couple of hours.
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On May 01 2012 02:54 SevenOfNine wrote:
Doesn't matter will take us 10000000000000000 years to get there because no one can figure out how to travel faster, in such high speed that it takes a couple of hours.
People said that we would never fly, go to space or the moon, travel faster than sound, have world population increasing, find alternative energy source.
But here we are always changing and surprising people.
We have nice stuff now because of people putting faith. Not just discarding the idea based on a grain of doubt.
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On May 01 2012 02:54 SevenOfNine wrote:
Doesn't matter will take us 10000000000000000 years to get there because no one can figure out how to travel faster, in such high speed that it takes a couple of hours.
Well read my post above yours
You can get there because time slows down / the universe shrinks when you accelerate.
The real problem is having enough energy to accelerate a ship to the needed speeds. Also the fact that humans can't accelerate very fast without becoming pancakes.
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On May 01 2012 02:49 Heh_ wrote:
There's been a lot of theory on how life evolved. People made primordial soup experiments and showed that RNA precursors can be generated by pure physical processes. Other groups have even shown how an RNA molecule can act as an evolving, self-catalyzing molecule. Please read up on scientific literature before spreading myths.
RNA is believed to be the very first self-replicating molecule. Ever heard of ribozymes? The RNA world is only feasible in a reducing environment free of molecular oxygen. Proteins came later in the equation. If you put proteins first, you've got yourself a chicken and egg scenario.
RNA has advantages over DNA: higher rates of mutation. The higher rate of mutation is good during the early stages of RNA evolution. However, once RNA molecules predominated, it was an evolutionary advantage to preserve a "good" sequence, which allowed the switch from RNA to DNA. However, RNA is not completely eliminated as DNA isn't flexible enough to perform certain functions of RNA.
oh wow, rna precursors can be generated by physical processes! that certainly explains everything about how the first fully functioning cell magically appeared. people tend to give too much importance to these experiments a lá urey-miller, just because you have all the parts you need doesnt explain how they assembled. thats not theory how life evolved, thats theory about how organic parts that could form life later on got created in the first place. dont mix these up please, since one is rather easy and the other one seems impossible still
and if you put rna first you dont have a chicken and egg scenario? im aware of the advantages of dna over rna but that doesnt explain how the switch could be ever accomplished. thats a chicken-egg scenario for you right there
also you manage not only to make your whole post in a unnecessarily arrogant tone but also seem to try to show off with information that is irrelevant. the exact conditions at the point where life first came into being are unknown, so it doesnt matter weather rna world scenarios only work in reducing atmospheres, what a weird thing to bring up
you cant even be sure it was earth where life as we know it now started. life might as well have first evolved on mars (which had good conditions before earth did) and got transplanted to earth by a meteroite. that obviously answers no questions and doesnt affect the question of extraterrestrial life much since the spread of life from other planets (panspermia) might be easy within the solar system but is pretty far fetched interstellar
i am aware of the advantages of dna over rna but that doesnt explain how its supposed to be possible to replace the very mechanism you need for reproduction by means of natural selection. if you know about biochemistry and you are certainly at least trying to come across as knowledgeable then you know how many enzymes are involved just in the reproduction of dna. its the typical problem of unguided evolution: you have a mechanism with a lot of complicated parts, and evolving one single part gives you no advantage, so how is it supposed to happen? all at once? thats another miracle right there...
i think i have to stop now otherwise i ll start rambling about evolution too much which isnt really on topic i guess...
On May 01 2012 02:45 heroyi wrote:
We understand our realm on earth very well i.e chemistry,biology, and physics. But again all of these things pertain to us and what we have experienced/perceive. For us to to say that only life can be created by water and carbon is ignorant. The periodic table is not finished and I am sure there are way more elements to be discovered not only on Earth but also out there somewhere. We haven't experienced/learned about everything that is possible out "there."
no no no no no no no no... to 'be sure' of something you should first have at least a BASIC understanding of that topic... if you had any clue about physics at all you would be rather sure of the opposite you said... its too bad that the certainty of peoples beliefs always seems to be inverserly proportional to how much people know about a given topic
please try not to be sure of anything, okay? we wont discover any more elements outside of high-energy physics laboratories, this i am ALMOST sure of, since it would violate pretty much everything we know about physics. and even if we did heavier elements wouldnt matter in any way for organic chemistry...
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On May 01 2012 03:21 summerloud wrote:[ Show nested quote +On May 01 2012 02:45 heroyi wrote:
We understand our realm on earth very well i.e chemistry,biology, and physics. But again all of these things pertain to us and what we have experienced/perceive. For us to to say that only life can be created by water and carbon is ignorant. The periodic table is not finished and I am sure there are way more elements to be discovered not only on Earth but also out there somewhere. We haven't experienced/learned about everything that is possible out "there." no no no no no no no no... to 'be sure' of something you should first have at least a BASIC understanding of that topic... if you had any clue about physics at all you would be rather sure of the opposite you said... its too bad that the certainty of peoples beliefs always seems to be inverserly proportional to how much people know about a given topic please try not to be sure of anything, okay? we wont discover any more elements outside of high-energy physics laboratories, this i am ALMOST sure of, since it would violate pretty much everything we know about physics. and even if we did heavier elements wouldnt matter in any way for organic chemistry...
No... it would not violate physics. Physics and chemistry say they should be more elements that we know of. With the conditions from star collapses and supernovae we should find traces of these higher elements. For someone that's complaining about everyone not having a basic understanding of the topic you must've not gotten a C yourself... read up, lots of active research is in this field. Here's a starter:
http://en.wikipedia.org/wiki/Island_of_stability
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On May 01 2012 02:50 hugman wrote:Show nested quote +On May 01 2012 00:44 ChosenSC2 wrote:
It doesn't matter cuz we'll never be able to get there? Especially in any sort of mass travel form ^^ You can get there. Relativity doesn't actually prevent you from travelling anywhere in a reasonable amount of time, because as you speed up the universe appears to shrink. At 1/sqrt(2) * c m/s you're effectively travelling at the speed of light, if you measure time in the traveller's reference frame and distance in the rest frame of your departure point. You could travel to Alpha Centauri and only age a few years, but people back on Earth would've aged millions of years.
lol that's nuts
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On May 01 2012 03:21 summerloud wrote:Show nested quote +On May 01 2012 02:49 Heh_ wrote:
There's been a lot of theory on how life evolved. People made primordial soup experiments and showed that RNA precursors can be generated by pure physical processes. Other groups have even shown how an RNA molecule can act as an evolving, self-catalyzing molecule. Please read up on scientific literature before spreading myths.
RNA is believed to be the very first self-replicating molecule. Ever heard of ribozymes? The RNA world is only feasible in a reducing environment free of molecular oxygen. Proteins came later in the equation. If you put proteins first, you've got yourself a chicken and egg scenario.
RNA has advantages over DNA: higher rates of mutation. The higher rate of mutation is good during the early stages of RNA evolution. However, once RNA molecules predominated, it was an evolutionary advantage to preserve a "good" sequence, which allowed the switch from RNA to DNA. However, RNA is not completely eliminated as DNA isn't flexible enough to perform certain functions of RNA. oh wow, rna precursors can be generated by physical processes! that certainly explains everything about how the first fully functioning cell magically appeared. people tend to give too much importance to these experiments a lá urey-miller, just because you have all the parts you need doesnt explain how they assembled. thats not theory how life evolved, thats theory about how organic parts that could form life later on got created in the first place. dont mix these up please, since one is rather easy and the other one seems impossible still and if you put rna first you dont have a chicken and egg scenario? im aware of the advantages of dna over rna but that doesnt explain how the switch could be ever accomplished. thats a chicken-egg scenario for you right there also you manage not only to make your whole post in a unnecessarily arrogant tone but also seem to try to show off with information that is irrelevant. the exact conditions at the point where life first came into being are unknown, so it doesnt matter weather rna world scenarios only work in reducing atmospheres, what a weird thing to bring up you cant even be sure it was earth where life as we know it now started. life might as well have first evolved on mars (which had good conditions before earth did) and got transplanted to earth by a meteroite. that obviously answers no questions and doesnt affect the question of extraterrestrial life much since the spread of life from other planets (panspermia) might be easy within the solar system but is pretty far fetched interstellar i am aware of the advantages of dna over rna but that doesnt explain how its supposed to be possible to replace the very mechanism you need for reproduction by means of natural selection. if you know about biochemistry and you are certainly at least trying to come across as knowledgeable then you know how many enzymes are involved just in the reproduction of dna. its the typical problem of unguided evolution: you have a mechanism with a lot of complicated parts, and evolving one single part gives you no advantage, so how is it supposed to happen? all at once? thats another miracle right there... i think i have to stop now otherwise i ll start rambling about evolution too much which isnt really on topic i guess...
I mentioned all these for a reason. That the precursors to life as we know it CAN be generated by physical processes, which enables a platform for evolution to act upon. Once we have proven that nucleotides can form in a reducing environment (because that's what the world was like before aerobic organisms dominated, I mentioned it for a reason), we have also proven that nucleotides can self-assemble into oligonucleotides and disassemble without any catalysis involved. Now, is it too far fetched to say that some of these oligos are able to undergo template-based replication? No, because we have ligase ribozymes. How did cells form? When you have a ribozyme, there is a evolutionary advantage to limiting its function of self-RNA molecules and not other random RNA molecules? How do you do this? You envelop the ribozyme and all necessary precursors in a lipid bilayer. Voila! You have a primitive cell (actually a liposome).
RNA and DNA nucleotides are structurally similar; they only differ at two areas. This structural similarity is key. An RNA-dependent RNA polymerase can undergo mutations at the catalytic site to allow DNA nucleotides into the active site, catalyzing new copies of DNA. This DNA now codes for a polymerase; now you have made the transition from RNA to DNA. Does this sound like a load of bullshit to you?
The whole part about Mars is just going off-topic.
I come across as arrogant, because I hate it when people take scientific facts and distort it in order to say something entirely different. That's what I feel you're doing. This is the internet, so there will be people dumb enough to accept everything at face value and then propagate the myth. An example is my friend on Facebook posting about the "alkaline diet", which is just a bunch of bullshit pseudoscience.
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On May 01 2012 03:21 summerloud wrote:[ Show nested quote +On May 01 2012 02:45 heroyi wrote:
We understand our realm on earth very well i.e chemistry,biology, and physics. But again all of these things pertain to us and what we have experienced/perceive. For us to to say that only life can be created by water and carbon is ignorant. The periodic table is not finished and I am sure there are way more elements to be discovered not only on Earth but also out there somewhere. We haven't experienced/learned about everything that is possible out "there." no no no no no no no no... to 'be sure' of something you should first have at least a BASIC understanding of that topic... if you had any clue about physics at all you would be rather sure of the opposite you said... its too bad that the certainty of peoples beliefs always seems to be inverserly proportional to how much people know about a given topic please try not to be sure of anything, okay? we wont discover any more elements outside of high-energy physics laboratories, this i am ALMOST sure of, since it would violate pretty much everything we know about physics. and even if we did heavier elements wouldnt matter in any way for organic chemistry...
Key word...
It is widely accepted and understood that we have much to learn in our physic. There is a lot of fields that have yet to be really explored which would help unlock many questions once understood.
We are always updating the chart (slowly). And besides if heavier elements were to be discovered how do you know that they wouldn't affect life in some way in other distance planets considering we know nothing about the element and the planets affected.
So no no no no and shame on you sir. Please refrain from insulting people. It makes you look weaker when your statement is already weak as it is.
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On May 01 2012 01:38 Dantelew wrote:Show nested quote +On May 01 2012 01:20 horsebanger wrote:
truthbombs:
we won't ever (ever) reach the other planets.
if we do find life it's extremely unlikely that it's a similar lifeform to the life on earth. it took billions of years to develop into humans and the fact that life excists out of water... not even gonna get started on that Thats a whole lot of truth you just dropped on us. Good thing you've elaborated and explained your claims with thorough and indepth facts to back your claims up and prove your so called "truthbombs". Explain why we wont ever (ever) reach the other planets. In our life time, probably not. In our childrens, probably not. But consider how far weve come in the past 200 years compaired to the entirety of our existence. It wasn't so long ago that the Earth was flat, and now we can fly around it for low cost in under a day, when 500 years ago it was called "exploring". Cell phones, which we now take for granted, would have been the size of a room a few decades ago. We now find new planets many light years away, and the best you have to say is "Meh, we wont get there anyways, and even if we do, we wont find anything," atleast back it up with some claim. I find the whole thing amazing, its fun to discuss, especially a lot of the chemistry people explaining why carbon and water based life forms are for all intents and purposes the only practical way life can be supported. I for one have always been in the camp of "Why do we need water?", but the explainations made a lot of sense.
1. google "lightyear"
2. google "closest exoplanet"
3. see how many lightyears away it is
enough said 
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On May 01 2012 02:50 hugman wrote:Show nested quote +On May 01 2012 00:44 ChosenSC2 wrote:
It doesn't matter cuz we'll never be able to get there? Especially in any sort of mass travel form ^^ You can get there. Relativity doesn't actually prevent you from travelling anywhere in a reasonable amount of time, because as you speed up the universe appears to shrink. At 1/sqrt(2) * c m/s you're effectively travelling at the speed of light, if you measure time in the traveller's reference frame and distance in the rest frame of your departure point. You could travel to Alpha Centauri and only age a few years, but people back on Earth would've aged millions of years.
Here's a graph I made to depict what you're talking about.
![[image loading]](http://i.imgur.com/ifOjh.png)
While going faster does get you there sooner, and that has a bound limit of the time it takes light to get to the same location to the viewer, the traveler can actually spend even less time traveling. After you go about 0.707 times the speed of light, you can get to a destination and age less than the time it takes light to go the same distance. If you were to go the speed of light, the trip would be instantaneous to you, while observers from home would see X years go by.
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Anyone read up on the recent theory by some Cornell people that smaller suns (than ours) have a wider range where planets could exist that can support life. This plus the fact that most of the suns in our galaxy are much smaller leads to the thought that maybe advanced lifeforms are all over the galaxy but just never bothered to check our solar system, given how unlikely it is for our sun to support life. Interesting thought
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We could reach Alpha Centauri in what 45 years if we have a hugh Solar Sail being power by lasers(?)... Of course we would need huge leaps in Engineering, Medicine, etc. But they could be used here locally, I belioeve there is one orbiting the Earth right now.
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On May 01 2012 04:21 horsebanger wrote:Show nested quote +On May 01 2012 01:38 Dantelew wrote:On May 01 2012 01:20 horsebanger wrote:
truthbombs:
we won't ever (ever) reach the other planets.
if we do find life it's extremely unlikely that it's a similar lifeform to the life on earth. it took billions of years to develop into humans and the fact that life excists out of water... not even gonna get started on that Thats a whole lot of truth you just dropped on us. Good thing you've elaborated and explained your claims with thorough and indepth facts to back your claims up and prove your so called "truthbombs". Explain why we wont ever (ever) reach the other planets. In our life time, probably not. In our childrens, probably not. But consider how far weve come in the past 200 years compaired to the entirety of our existence. It wasn't so long ago that the Earth was flat, and now we can fly around it for low cost in under a day, when 500 years ago it was called "exploring". Cell phones, which we now take for granted, would have been the size of a room a few decades ago. We now find new planets many light years away, and the best you have to say is "Meh, we wont get there anyways, and even if we do, we wont find anything," atleast back it up with some claim. I find the whole thing amazing, its fun to discuss, especially a lot of the chemistry people explaining why carbon and water based life forms are for all intents and purposes the only practical way life can be supported. I for one have always been in the camp of "Why do we need water?", but the explainations made a lot of sense. 1. google "lightyear" 2. google "closest exoplanet" 3. see how many lightyears away it is enough said
That is like the worst counter argument I've ever read. What is this, 4th grade debate?
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so if traveling in the speed of light makes the trip seem instant, how the heck is it possible 2 know when 2 stop? ^^
"oh shitz, i just traveld 50 million lightyears and just pressed luanchbutton".
Univers map needed ^^
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The problem isn't the speed of light. The problems are twofold. The exponential nature of the rocket formula and the limits of human physiology.
Every time you want to go faster you need exponentially more fuel and all that fuel is only spend to accelerate the fuel you need later. Now this applies to chemical rockets very much. But even if you have a fusion engine, it still holds but is much much much less of a problem for practical purposes.
Don't forget you also need fuel to slow down. It's just as much of an issue as speeding up.
Once you have an anti matter engine and fuel to fuel fuel becomes less of a problem. Then it's the problem of acceleration and g forces. Ideal would be to accelerate with 1 g. But if you do you will be accelerating for a long long time before you get anywhere close to light speed. It would take a year. So you can have a nice graph with the time in years it takes to cover 5 ly and it will go to almost zero very near 1 c, it ignores accelerating. And then again you need to slow down. So when you finally get to a nice fraction of light speed, you need to slow down again.
An average human male may weight 70 kg. That's 50 kg of water and 20 kg of dry weight. Now cryogenic sleep is nice and all, but it would be nicer if we can get rid of all that useless water as well.
All the DNA in a human body should weight near about 1/100th of a gram. But that's millions of cells. You only need one copy of DNA to build a human. So when you use nanobots with DNA, you don't need to send people and you don't have any problems with mass or with g forces.
The weight of the nanobots used to build the installation that can create a human out of the water and carbon locally available don't need to have much mass. In theory 1 nanobot could do it.
On May 01 2012 05:41 V6 wrote:
so if traveling in the speed of light makes the trip seem instant, how the heck is it possible 2 know when 2 stop? ^^
"oh shitz, i just traveld 50 million lightyears and just pressed luanchbutton".
Univers map needed ^^
You can't reach the speed of light. If you do you are frozen in time and you won't ever get to 'press the button'.
If you are very near, being just a few nanoseconds off means you miss your target by a large margin. The closer to the speed of light, the bigger the distance and the higher the precision needed. As you approach the speed of light, you approach overshooting your destination by an infinite distance and you need infinite accuracy to stop exactly at the right moment.
But this is all theoy since you have to accelerate.
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On May 01 2012 05:43 Miyoshino wrote:The problem isn't the speed of light. The problems are twofold. The exponential nature of the rocket formula and the limits of human physiology. Every time you want to go faster you need exponentially more fuel and all that fuel is only spend to accelerate the fuel you need later. Now this applies to chemical rockets very much. But even if you have a fusion engine, it still holds but is much much much less of a problem for practical purposes. Don't forget you also need fuel to slow down. It's just as much of an issue as speeding up. Once you have an anti matter engine and fuel to fuel fuel becomes less of a problem. Then it's the problem of acceleration and g forces. Ideal would be to accelerate with 1 g. But if you do you will be accelerating for a long long time before you get anywhere close to light speed. It would take a year. So you can have a nice graph with the time in years it takes to cover 5 ly and it will go to almost zero very near 1 c, it ignores accelerating. And then again you need to slow down. So when you finally get to a nice fraction of light speed, you need to slow down again. An average human male may weight 70 kg. That's 50 kg of water and 20 kg of dry weight. Now cryogenic sleep is nice and all, but it would be nicer if we can get rid of all that useless water as well. All the DNA in a human body should weight near about 1/100th of a gram. But that's millions of cells. You only need one copy of DNA to build a human. So when you use nanobots with DNA, you don't need to send people and you don't have any problems with mass or with g forces. The weight of the nanobots used to build the installation that can create a human out of the water and carbon locally available don't need to have much mass. In theory 1 nanobot could do it. Show nested quote +On May 01 2012 05:41 V6 wrote:
so if traveling in the speed of light makes the trip seem instant, how the heck is it possible 2 know when 2 stop? ^^
"oh shitz, i just traveld 50 million lightyears and just pressed luanchbutton".
Univers map needed ^^ You can't reach the speed of light. If you do you are frozen in time and you won't ever get to 'press the button'. If you are very near, being just a few nanoseconds off means you miss your target by a large margin. The closer to the speed of light, the bigger the distance and the higher the precision needed. As you approach the speed of light, you approach overshooting your destination by an infinite distance and you need infinite accuracy to stop exactly at the right moment. But this is all theoy since you have to accelerate.
The argument was good until you started talking about breaking down a human. There's more to a human than just DNA. If you exclude random mutations (that occur ~3 times per cell division), then there's no way that these so-called nanobots can distinguish between a 2 year old child and an 80 year old man. Then there's environmental factors, memory (no one really knows how the brain works), and a host of other factors. You're stuck with trying to transport the whole human. The best thing you can do is to make the person go on a diet =D
Then the acceleration turns said human into pulp.
Edit: typo
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we are like parasites. We infested the earth and now moving on to the next planet
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We are aliens.
Life could never ever have been there since the begining of earth formation.
Dusts and space debris gathering around the core during millions of years could not have permitted life,
But the multitude of meteorites impacts on our earth could have permitted some organism trapped into ice to smash the earth and somehow managed to survive (unicellular organisms are extremely robust life forms).
Exactly like how pollen works on earth. If you see a flower in a field, it's hard to imagine that there is no other nearby.
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EPT
