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Life Could Have Evolved 15 Million Years After the Big Bang, Says Cosmologist 312

Posted by Unknown Lamer from the star-trek-explained dept.
KentuckyFC writes "Goldilocks zones are regions around stars that are 'just right' for liquid water and for the chemistry of life as we know it. Now one cosmologist points out that the universe must have been through a Goldilocks epoch, a period in which warm, watery conditions could have existed on almost any planet in the entire cosmos. The key phenomenon here is the cosmic background radiation, the afterglow of the Big Bang which was blazing hot when it first formed. But as the universe expanded, the wavelength of this radiation increased, lowering its energy. Today, it is an icy 3 Kelvin. But somewhere along the way, it must have been between 273 and 300 Kelvin, just right to keep water in liquid form. According to the new calculations, this Goldilocks epoch would have occurred when the universe was about 15 million years old and would have lasted for several million years. And since the first stars had a lifespan of only 3 million years or so, that allows plenty of time for the heavy elements to have formed which are necessary for planet formation and the chemistry of life. Indeed, if live did evolve a this time, it would have predated life on Earth by about 10 billion years."
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Life Could Have Evolved 15 Million Years After the Big Bang, Says Cosmologist More

Life Could Have Evolved 15 Million Years After the Big Bang, Says Cosmologist

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  • Millions of years of life-supporting conditions (Score:5, Funny)

    by Anonymous Coward on Monday December 09, 2013 @06:50PM (#45645445)

    I wonder if that was long enough to produce lush gardens with apple trees.

    • I wonder if that was long enough to produce lush gardens with apple trees.

      That's silly. Everyone knows that happened only 6,000 years ago!

  • ah yes, a time when (Score:4, Funny)

    by Bramlet Abercrombie ( 1435537 ) on Monday December 09, 2013 @06:57PM (#45645519)
    His vast Noodly Appendeges still bathed the entire cosmos is a fine tomato based sauce.

  • Duh.... (Score:5, Funny)

    by Lumpy ( 12016 ) on Monday December 09, 2013 @07:02PM (#45645569) Homepage

    Everyone knows the Time Lords are one of the first races of the galaxy.

    • Re: (Score:2)

      by rssrss ( 686344 )

      The Time Lords are mere children compared to Cthulhu and the Great Old Ones.

      "These Great Old Ones, Castro continued, were not composed altogether of flesh and blood. ... But although They no longer lived, They would never really die. They all lay in stone houses in Their great city of R'lyeh, preserved by the spells of mighty Cthulhu for a glorious resurrection when the stars and the earth might once more be ready for Them. ..."

      "The Call of Cthulhu" by H.P. Lovecraft (1928)

  • This is frightening (Score:5, Interesting)

    by JoshuaZ ( 1134087 ) on Monday December 09, 2013 @07:07PM (#45645605) Homepage

    This is pretty scary. One of the major unsolved problems right now is the Fermi problem- why we don't see any signs of civilizations other than our own, not just no radio transmissions but no Dyson spheres (and yes, we've looked http://home.fnal.gov/~carrigan/infrared_astronomy/Fermilab_search.htm [fnal.gov], stellar uplifting, ringworlds or the like. Whatever is blocking this is the so-called Great Filter https://en.wikipedia.org/wiki/Great_Filter [wikipedia.org]. Now, some of the Filter could be in our past. It may be tough for life to arise or for multicellular life to arise, etc. However, the more disturbing possibility is that it exists in our future: maybe civilizations before they can spread out manage to wipe themselves out with their technologies, such as through nuclear war, bad nanotech, engineered bioweapons, resource depletion, environmental damage, or something we haven't even thought about before.

    Over the last few years, more and more evidence has suggested that a lot of the obvious filtration events in the past aren't serious filters. For example, we've found that planets are common. This is not only an example of more such evidence, but it suggests that if life got started it would have had billions years more to evolve, meaning that evolutionarily based filters will be substantially less effective. Worse, it undermines one of the easier ways to try and get around a filter, to suggest that the conditions for complex life didn't arise until recently. There are serious problems with that idea already (especially the fact that life on Earth spent hundreds of millions of years in near stasis), and this makes those problems even more severe. If this checks out, it will be strong evidence that a substantial portion of the filter is in the future. If so, it is likely that the Filter is something that is going to happen to us within the next few hundred years, since it gets harder to wipe out a civilization once they spread beyond their initial planet, and most obvious things that would do so are also more noticeable.

    • > However, the more disturbing possibility is that it exists in our future: maybe civilizations before they can spread out manage to wipe themselves out with their technologies, such as through nuclear war, bad nanotech, engineered bioweapons, resource depletion, environmental damage, or something we haven't even thought about before.

      Reality TV. I tell ya.

    • Re:This is frightening (Score:4, Insightful)

      by Anonymous Coward on Monday December 09, 2013 @07:28PM (#45645779)
      There is no paradox. The laws of physics are the same all over, it's just not possible to build the kind of things you'd see at stellar distances. Sorry to burst your bubble. The real paradox is why people still think we should look for impossible things. Our own civilization went from spark gap generators to low power ultra-wideband and fiber optic technology within a century.

      At cosmological time scales that's a blip. Our radio waves will most likely never be heard again just like we'll never hear theirs.

      For the record I think that there is life everywhere in the universe because the laws of physics will be the same.

      But let me guess, you believe the aliens use magical particles like tachyons and gravitons to communicate and we're just too stupid to figure it out but when we do we'll be invited to the galactic fraternity, right?

      • Re:This is frightening (Score:5, Insightful)

        by boristhespider ( 1678416 ) on Monday December 09, 2013 @07:42PM (#45645907)

        mod up.

        From the GP, "why we don't see any signs of civilizations other than our own, not just no radio transmissions but no Dyson spheres (and yes, we've looked http://home.fnal.gov/~carrigan/infrared_astronomy/Fermilab_search.htm [fnal.gov] [fnal.gov], stellar uplifting, ringworlds"

        What would you expect to see? Realistically? We've been listening for about 50 years (less, on a semi-professional basis). That's fifty years. Civilsation on Earth has been going about 5000 or so (very roughly, I'm not in the mood for pointless arguments about what constitutes "civilisation" when we compare Neolithic with Mesolithic, thanks). Mankind has been around for very roughly 100,000. 100,000 years is *nothing*, and yet for almost all of that time we've been totally invisible. It's only in the last 100 years that we've been blasting radio waves out to the cosmos. For the last decade or so, much of that has been encrypted and therefore looks like noise. It may not look like *random* noise, but it looks like noise. How do you expect an alien race, less than ten light years away, to possibly decrypt communications sent in a language they don't speak, through a character set they don't use, through mappings that make no sense to their computers, passed through encryption they don't have a handle on? They can't, it's a foolish belief. Even without encryption, modern digital transmission is refined enough that it's unlikely an alien race would be able to rapidly decode our transmissions, if at all.

        So if you accept this line of argument, we've basically transmitted approximately a century's worth of information out to the heavens, in a very thin shell of expanding radiation. That radiation grows horrifically weak very quickly and would be hard to pick up over the Sun's background noise. What we're expecting, if an alien race is to even know of our existence, is that they are at the exact point in their development that they can somehow pick out our unencrypted transmissions above the Sun's natural noise, and then somehow decode those transmissions and make sense of them. Most of those transmissions are crappy 1970s sitcoms, or endless radio adverts. Fortunately no-one will know this, because it relies on there being a civilisation extraordinarily local to us, at exactly the same level of development as us, and actually listening to the outside world. Those chances are excruciatingly poor.

        That goes the other way round.

        For the rest, Dyson spheres? A myth. Freeman Dyson is close to a legend, but Dyson spheres are not a realitic proposition - not for us, and not for anyone.

        Ringworlds? Lol.

        I don't even know what is meant by "Stellar uplifting". If it involves doing anything to do with manipulating the Sun... yeah, you go ahead, I'll do something less likely to kill me.

        • The issue isn't the use of radio waves as an incidental. Radio waves come out from deliberate attempts by civilizations try to set up beacons and say "Hey! We're here." I agree that are normal radio use is insufficient to be detected. Heck, even if you were at Alpha Centauri, telling that our radio transmissions are not natural would be tough. As to the large scale projects in question, simply calling them myths and saying "lol" is not a logical response, but essentially the absurdity heuristic http://lessw [lesswrong.com]

        • Re: (Score:3)

          by tippe ( 1136385 )

          On the whole, I agree with your post, but FYI: encrypted data may very well look like noise when you are looking at it in its digital "baseband" format (the raw cyphertext bits), but once it's encoded and modulated for transmission (FM, QAM, whatever), it no longer looks like random noise so much any more. Anyone with a suitable antenna and a means of displaying the frequency content of the received signal will immediately see a peak (or peaks) that corresponds to your transmission (assuming they can recei

        • Re:This is frightening (Score:5, Interesting)

          by wvmarle ( 1070040 ) on Monday December 09, 2013 @10:31PM (#45647195)

          We can probably ignore the sun's background radiation: if an alien civilisation is advanced enough to see our planet next to the sun in visible light (reflection from the sun's rays) they can probably focus enough to pick up our radio signals (the sun's radio frequency waves will not be deflected by the Earth much if at all). The fact that there are radio signals coming from our planet should be the giveaway. No other planet in our solar system is producing such signals. And that's of course assuming this alien entity is using radio waves themselves for communication, and as such thinks it's a good idea to look for radio waves as a sign of the presence of intelligent life.

          Same for this SETI, I don't think we'll ever be able to understand alien signals beyond the mere fact that they are out there.

        • Re: (Score:3)

          by AmiMoJo ( 196126 ) *

          You are thinking to narrowly. You would expect to see evidence of advanced civilizations, if not from their engineering works than from deliberate attempts to be noticed. It is unlikely that they would all have some kind of "prime directive".

          We already beam messages and send probes into space. An advanced civilization that has solved its resource problems would likely make am effort to explore and contract other races, just like we do, but on a much larger scale.

      • Re:This is frightening (Score:5, Informative)

        by JoshuaZ ( 1134087 ) on Monday December 09, 2013 @07:44PM (#45645923) Homepage

        , it's just not possible to build the kind of things you'd see at stellar distances.

        I'm curious why you think that given that for example a small Class A stellar engine https://en.wikipedia.org/wiki/Stellar_engine [wikipedia.org] appears to be buildable with what we know about materials science. And this isn't the only example of such. The requirements are purely on the amount of resources that need to go in, not physical limitations. Yes, some specific suggestions would require materials that look impossible. For example, an inflexible single piece ringworld is likely to be impossible (the tensile strength among other requirements make it implausible). But many megascale structures aren't in that category.

        But let me guess, you believe the aliens use magical particles like tachyons and gravitons to communicate and we're just too stupid to figure it out but when we do we'll be invited to the galactic fraternity, right?

        No. Absolutely not. First note that tachyons and gravitons aren't "magical" there's a massive difference between theoretical particles consistent with the laws of physics. It is likely that tachyons do not exist, since they'd either allow causality violations (unlikely) or they'd not allow communication. Similarly, thinking that one could use something like gravitons to communicate is just silly since they'd be incredibly weak. I don't have any belief in some galactic fraternity, but your attempt to pigeon hole rather than read what people write is interesting. Concerns about the Great Filter arise specifically from there being no evidence of anything remotely like that. If there were any reason to think that was at all likely, we could breath a lot easier.

        For the record I think that there is life everywhere in the universe because the laws of physics will be the same.

        So, we're in complete agreement here. But the problem is what this leads to: it means that out of the civilizations, none of them are trying anything on a large scale, not even the few more ambitious ones. This suggests that once life gets sufficiently advanced, it gets wiped out somehow. The Great Filter is a serious problem: Nick Bostrom and his colleagues at the Future of Humanity Institute for example have given this a lot of thought. See for example http://www.nickbostrom.com/extraterrestrial.pdf [nickbostrom.com]. And this is very much the sort of problem where if it exists, pretending it doesn't won't make it go away.

      • Re: (Score:2)

        by khallow ( 566160 )

        it's just not possible to build the kind of things you'd see at stellar distances.

        Actually, it is. Dyson spheres for example are such a case. One doesn't build them out of a single shell, but rather out of a cloud of satellites. So the hard engineering requirements are that you build a lot of satellites and that you figure out traffic control. Neither is physically impossible.

        That structure would be visible to anyone with our level of technology (eg, the Hubble Space Telescope) in our galaxy who has line of sight.

        Also there's the matter of local structures. Why aren't there obvious

    • Re: (Score:3, Interesting)

      by Charliemopps ( 1157495 )

      We can't see extra-solar civilizations because our technology sucks. We don't even know whats on the bottom of our own oceans and you're thinking Aliens that are probably millions of years more advanced that us at the very least would still use Radio waves and think of a Dyson Sphere as anything more than obserd joke? Do you think that we'll still be emitting radio waves in even 500 years time? How about 1000?

      • Radio waves aren't useful as much as a method of communication from incidental power. Indeed, even in the last few years, as our radio systems have become more efficient, Earth has become on many frequencies darker than it was in the 1960s. The key isn't use of radio waves as an incidental, but as a method a culture might deliberately use to say "hey! Look! We're out here!" As to Dyson spheres, they are one example of many possible large scale projects, but I'm curious why you consider them in particular to

    • Well known filter is currently active (Score:5, Interesting)

      by Anonymous Coward on Monday December 09, 2013 @07:45PM (#45645931)

      The following is nothing new, but few people want to face up to what it really means for us. The 6th Mass Extinction [wikipedia.org] is well under way, and it has nothing to do with cuddly pandas and (less cuddly) tigers and rhinos disappearing. It's the microscopic life such as oceanic biota, nearly all of it unseen by most people, that's disappearing at a devastating pace like nothing that's ever happened before on this planet.

      We can live without the top-end mammals that make the extinction news on the TV. We can't live without the microbiota. We are not independent of them, they keep the biosphere running and our crops producing, and without the biosphere we are no more.

      The collapse of biodiversity is, on geological scales, vertically downwards, and at some point it simply hits the zero axis. It could happen even more suddenly if a tipping point is reached, because species are inter-dependent. The current decline is not the normal sort of gradually falling curve as seen in the past 5 extinctions. On the biodiversity graph, this event is an abrupt termination of all life. You can't argue with the biodiversity curve.

      We don't really need more Great Filter theories. This one is not a theory, it's measured, and it's quite enough all by itself.

      • Re: (Score:3)

        by doom ( 14564 )

        The first thing everyone *used* to say to the Fermi Paradox is "maybe they all blow themselves up in nuclear wars".

        This kind of remark is very parochial and a clear sign of Not Getting It.

        Maybe 99% of them blow themselves up. Maybe another 99% of the ones that slip through that create an eco-catastrophe. Maybe another 99% get nailed by something else we don't know about.

        These factors all get applied to a *huge* starting number, they cut the result way down but they don't reduce it to zero, and zero

    • I agree, I ran the Math, and basically considering the distances involved and the time-frame, I am fairly convinced we will never find aliens and never colonise space (to any significant degree).

      Either space colonization is completely impractical, or all advanced civilizations quickly become extinct, or for some reason all decide to never leave their planet.
      Only one of these ideas really makes any sense, in my mind. I think your bounds are too small personally, I think something on the order of the next ten

    • My money's on the idea that our universe is just an incubator for new life. A nursery. Stars are heat lamps, planets are nests, etc. Eventually, technological civilizations grow out of childhood, learn enough about their surroundings to realize there's much more out there, and their tech develops enough to let them escape and join the party outside the universe, where all the other super-old civilizations are. Crazy rambling, I know, but it's a good seed for ideas.

    • Re: (Score:3)

      by Evtim ( 1022085 )

      You know what's even more frightening? Your post led me to dig a bit into the Fermi paradox and following one link or another I arrived at the commemoration event [35th anniversary of the Wow! signal] at Aresibo. Wiki reads:

      In 2012, on the 35th anniversary of the Wow! signal, Arecibo Observatory beamed a response from humanity, containing 10,000 Twitter messages, in the direction from which the signal originated.[13][14] In the response, Arecibo scientists have attempted to increase the chances of intellige

  • The problem with theories of extra-terrestrial life is: the probability of us being here is 1, regardless of the a-priori probability of life being created on this planet.

    Here's a nice way to look at it.

    Consider the formation of the first life-generating molecules, like DNA, or the first ribosomes. You can compare the corresponding probability (i.e., of those molecules actually forming) to the following situation. Assume you have a grid of infinite times infinite squares (our analogy of the universe). Each

    • 2^1,000,000 should of course been 2^-1,000,000, a rather small number.

      Another question: the example was for a 2-dimensional universe; will the average distance between prescribed NxN patterns increase or decrease with increasing dimensionality?

    • One could look at it this way -- maybe there are billions of planets in the goldilocks zone, with liquid water, and no life whatsoever. This could be good news, in a way. The less good news is that whatever microbes, plants, animals, we need we'll have to take with us or do without.

      • Re:Problem (Score:4, Interesting)

        by boristhespider ( 1678416 ) on Monday December 09, 2013 @07:23PM (#45645731)

        That would be true regardless of whether there was life on other planets or not. No matter how closely those planets resembled Earth, they're not Earth, and while they *might* provide us with every vitamin and protein we need it does seem somewhat unlikely...

  • If we ever meet any life that evolved from back then we shall microbes to them as microbes are to us. A curiosity to be studied, and shelved, dissected and put on display.

  • But I've always figured self-replication was as common in the universe as stalagmites or simple carbon isomers. There's nothing really special about it... it just happens.

    • Re:Just my opinion (Score:5, Funny)

      by 140Mandak262Jamuna ( 970587 ) on Monday December 09, 2013 @07:38PM (#45645865) Journal
      I found this in Panda's Thumb: [pandasthumb.org]

      I don’t know about you evilutionists. But to me, these stalactites and stalagmites look very much designed. Only dogmatic Darwin worshipers could be dumb enough to believe that these stalactites and stalagmites would know where to start growing so that eventually meet at a point, conjoin, become a pillar and hold the roof of the cave up.

      There is symmetry in the formations, symmetry means information, symmetry means reduction in disorder, reduction in disorder is reduction in entropy and entropy can not be reduced by random naturalistic mechanistic processes. If these formations are “natural” then they violate the Second Law of Thermodynamics. The pathetic inability of the theory of evolution to account for the cave formations completely disproves any credibility the Big Bang Theory might have. It stretches the credulity of the American Public, 62% of whom don’t believe evolution anyway, that these scientists would confidently see amino acids and methane in planets and moons in the sky, when they cant see that mud-to-stalactite evolution is impossible.

      • They look as designed as the calcium build up in my shower..

      • Wait what? Mud dripping down from a ceiling eventually builds a pile of mud that eventually meets the mud dripping down from the ceiling and this is evidence of intelligent design and the reduction of entropy?

        Had I only known before I accepted physics, geology and evolution...(sigh).

        If there are more evolved beings out there observing us, I feel they may just, at times, shake their heads (what ever it may be). I know I do.

      • Re: (Score:2)

        by Nimey ( 114278 )

        Therefore time cube.

  • Too little time... (Score:4, Insightful)

    by Evil Pete ( 73279 ) on Monday December 09, 2013 @07:35PM (#45645835) Homepage

    This (a goldilocks era) is a really interesting idea which seems obvious now that someone has brought it up. But it would be brief. Think of it this way, for millions of years the cosmic glow would be hot, too hot. Planets form, create magma oceans ... still too hot. Finally, the big bang glow cools to around 300K, but the Earth is likely still a magma ocean, or is still hot from trying to be in equilibrium with a hot universe plus internal heat from all those radioactives. Life aronse on Earth fairly rapidly, but it is unlikely that it took just a few million years. Even if it did arise on one of these worlds, it took billions for multicellularity to arise on Earth. After the brief goldilocks era what then? The sky would continue cooling, the worlds that were desirable places for new life would freeze, the ones that were too hot might now be suitable for life. In the end there would be little benefit. But there would still be planets around where life could start, though it might be complicated and very dangerous at this time.

    • Re: (Score:2, Informative)

      by Kuroji ( 990107 )

      Don't be silly. At that point in time there were no planets at all -- hydrogen was about the only thing in the universe, until stars started burning hot and fast to put heavier elements into the universe.

      This article is pointless conjecture. Conditions for life as we know it could not have possibly existed, due to a lack of pressure, gravity and a planet to live on, materials required to put anything together, etc. The only thing that this shows is that it was warm enough for life, while utterly disregardin

      • Um... did you read the article? Search for this sentence: "The first is the question of whether planets could have formed at all at this stage of the universe." and then keep reading from there. tl;dr? There would likely have been plenty of time and resources for planet formation.

        I'll just point out that this "pointless conjecture" comes from a scientist who has contributed more to our understanding of the universe than most people posting on this thread.

      • TFS talks about stars existing, and burning up (producing all kinds of heavier elements in the process) in just 3 mln years. If so, just 10 mln years after the Big Bang there would have been all kinds of elements present in the universe.

  • Warm and dark (Score:5, Interesting)

    by FridayBob ( 619244 ) on Monday December 09, 2013 @07:45PM (#45645929)

    That period in the history of our universe may have been warm, but I imagine that, at the time, the average hospitable planetary surface would have been pretty dark. After all, if the Goldilocks zone is what you get without having a nearby star at all, then having a star nearby would make things too hot. So, any planetary surface suitable for life to evolve on would have been a necessarily dark place.

    An unfortunate consequence of this warm universe is that it will have taken longer for planetary bodies to cool down after their formation. The question is, would even a Mars-sized body have have enough time to form and cool down so that standing water could have existed on its surface during this Goldilocks era? Somehow, I doubt it.

    As the background temperature cooled to below the freezing point of water, the habitable volume of the universe suddenly became restricted to the areas around stars. These early stellar Goldilocks zones will initially have been huge, but would soon become much smaller. And as they became smaller, they also became more brightly lit.

    • That period in the history of our universe may have been warm, but I imagine that, at the time, the average hospitable planetary surface would have been pretty dark. After all, if the Goldilocks zone is what you get without having a nearby star at all, then having a star nearby would make things too hot. So, any planetary surface suitable for life to evolve on would have been a necessarily dark place.

      And I thought planets normally form in conjunction with stars, out of the disk of dust around them? Or are there different theories on the formation of planets, specifically in that period? Also while there were heavier elements (needed to form solid rocks, not just life), there wasn't very much of such material.

      • And I thought planets normally form in conjunction with stars, out of the disk of dust around them? ...

        Perhaps, but not necessarily. Studies published earlier this year about of microlensing events seen by the Kepler space telescope suggest that there may be trillions of rogue planets drifting between the stars of our galaxy alone. Did they all originally form around stars? Maybe, but regardless, if they exist now then why could there not have been at least a fraction of these bodies present during the Goldilocks era?

        ... Also while there were heavier elements (needed to form solid rocks, not just life), there wasn't very much of such material.

        Very true, and I've also heard it said that with even more of the stuff available in the far

  • "There are things in the Universe billions of years older than either of our races. They are vast, timeless, and if they are aware of us at all, it is as little more than ants and we have as much chance of communicating with them as an ant has with us. We know. We've tried and we've learned that we can either stay out from underfoot or be stepped on. They are a mystery and I am both terrified and reassured to know that there are still wonders in the Universe, that we have not explained everything. Whatever

  • Was the early universe, like the first second after the big bang, a separate "regime" to what we see today? ie the energy density of free space was so high that reactions could happen so much faster that anything that could be called life (in whatever passed for matter, or substrate) evolved, lived, learned, observed its universe, died within that second and the universe kept cooling?

    Subjectively that second would have been like billions of years to them. And could they have left traces, like manipulating t

    • Whether you could form "complex" and "interesting" structures depends on how many layers "deeper" physics goes than the current level of understanding. Consider how many molecules it takes to make a human brain: to form life, much less intelligent life, you need a vast number of simple units able to subtly interact for long periods (relative to their typical interaction timescale) before being ripped apart and reorganized. If string-theory-like structures are the "fundamental" constituents of the universe,

  • A several million year period where life could have developed is not much time considering that it took several billion [wikipedia.org] years for life on earth to evolve from simple cells to multi-cellular organisms.

    • It took several billion years because the atmosphere lacked oxygen and it took them (cyanobacteria) several billion years of emitting oxygen by photosynthesis to go to the next stage. If oxygen was already available, they could have saved a couple of billion years.

      The theory of punctuated equilibrium holds that there were long periods of stasis and sudden bursts of evolution when the conditions changed rapidly. So if the statis periods were short plenty of evolution could take place in a few million years

  • So the universe once had the perfect living conditions for species 8472 [wikipedia.org]/

  • To locally decrease entropy (as life must) you need both an energy source and an energy sink (i.e. somewhere to send your waste heat.) I think this era of the universe would have problems with the energy sink bit. If the coldest available sink is 270K, life would need to be much hotter to be able to use it, which is likely too hot for complex organic reactions.

    Having said that, a little bit after (say when the microwave background was at 200K) might have been pretty good for life. Now you only need a little

    • Life gets along just fine with nothing colder than a 270K heat sink --- unless you don't think anything can live indoors or underground without a direct view of the cold sky. In fact, the majority of life does better when not in good contact with a 270K thermal bath (ice temperature). You need some heat sink, but life can get along just fine at, e.g., 310K (human body temperature) with a 300K (room temperature) environment as a heat sink.

  • The main limitation of "Goldilocks Zone" is in the imagination. Papa Bear's porridge was the right temperature for Papa Bear. We are defining "life sustaining" as what would sustain our lives. Who would have predicted "vent and seep" communities on the ocean floor, living from heat from fissures? But those are easy... What's really hard to understand are life forms that have a civilization occur in a millisecond, or a synapse that takes a million years...

    • What's really hard to understand are life forms that have a civilization occur in a millisecond, or a synapse that takes a million years...

      Well, with respect to that last one, don't you have politicians where you live?

  • Quoting from the end of the article:
    > Foremost among them will be whether there is any mechanism that could have allowed life from
    > this era, if it did evolve, to have survived as the universe cooled down. And if so, whether there
    > might be evidence of it today.

    Seems like it would be possible if a world was in free space during the warm period and then was captured by a sun as the background radiation cooled. Yeah, the handoff would have to be pretty precisely timed, but if there were millions of s

  • Don't forget you need a smattering of heavier elements for life. So you need to wait through a couple cycles of super novas to get a decent distribution of elements over atomic 5 (Fe)... including carbon. Hving this stiff made in a star isn't enough, it's gotta accrete into a planet after.

  • Would the chemistry leading to primitive life, and the very earliest life forms, need cooler places? If all of space is permeated by comfy temperatures, where could things happen needing to happen at cooler temperatures? Maybe evaporation in certain places could lead to that, or some other nonequilibrium situations.

    Amoebas gotta keep their primitive beer cold!

  • OK, so the heavy elements began to be manufactured after just 3 million years, but were they manufactured in large numbers?

    And how long does it take for those heavy elements to disperse through the universe and then coalesce into a planet around a suitable star? Seems like it might be longer than 15 million years.

    And life took 500 million years to get started after Earth formed. For sure, for some of that time the Earth was too hot for life to occur but 15 million years seems too short for anything useful t

  • A Long Time Ago (Score:3)

    by 427_ci_505 ( 1009677 ) on Tuesday December 10, 2013 @02:29AM (#45648231)

    In a Galaxy Far, Far Away...

  • Thermal death (Score:3)

    by Framboise ( 521772 ) on Tuesday December 10, 2013 @08:22AM (#45649511)

    Life is an out-of-thermal equilibrium process, which needs the cold part of the universe to export the produced entropy necessary for sustaining life. Life does not really needs solar *energy* (otherwise earth would warm up). Actually the energy of the low entropy photons of the sun is transformed and radiated away in cold space as more numerous infrared photons. No energy is gained in average, the precise amount of solar energy received from the sun is radiated away into space, but entropy is exported. This entropy export is crucial for allowing life.
    Incidentally this explains why life does not respect the second principle of thermodynamics since the biosphere is not in thermal equilibrium.

    Once this understood, the scenario of the cosmologists appears completely flawed, as the cold part of the process is missing.

         

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