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

Unknown Lamer posted about a year ago | from the star-trek-explained dept.

Space 312

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

Anonymous Coward | about a year ago | (#45645445)

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

Re:Millions of years of life-supporting conditions (0)

Anonymous Coward | about a year ago | (#45645487)

Not sure about the genesis reference, but it seems it was enough time for the emergence of DNA. Panspermia gets one more piece in support.

Re:Millions of years of life-supporting conditions (3, Insightful)

MightyMartian (840721) | about a year ago | (#45645543)

And how exactly does panspermia get a lift here? It's not as if catching a lift in interstellar space would have been any easier at that stage than now. I suspect with the level of energetic activity from quasars and the like, it would have been even less likely.

Re:Millions of years of life-supporting conditions (2)

nut (19435) | about a year ago | (#45645841)

I'm assuming the GP's argument is that the higher than previously expected possibility of life-bearing planets early in the life of the universe increases the possibility of panspermia, all other things being equal.

The probability of panspermia is product of (at least) two other possibilities:
1.) Life exists somewhere
2.) Life is carried though space from one planet to another by some means.

Regardless of the probability of the latter, (which may be infinitesimal in any case) increasing the probability of the former at any point in time increases the overall probability of panspermia.

Re:Millions of years of life-supporting conditions (1)

SJHillman (1966756) | about a year ago | (#45645845)

Panspermia gets support because the longer life has been around, the greater the chance it could have happened.

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

symbolset (646467) | about a year ago | (#45646175)

The roads were a lot shorter back then.

Re:Millions of years of life-supporting conditions (5, Insightful)

tnk1 (899206) | about a year ago | (#45645713)

I always wondered what the point was with considering panspermia. If life could have appeared anywhere in order to make it to Earth, it could have just as easily originated on Earth to begin with. There's nothing miraculous about Earth, but there is nothing sub-standard about it either.

It would be interesting to know if terrestrial life started elsewhere, but what problems does that hypothesis solve? The only one I can think of is why all almost all Star Trek aliens look like humans with different foreheads.

Re:Millions of years of life-supporting conditions (2)

SJHillman (1966756) | about a year ago | (#45645887)

Star Trek's proliferation of humanoids was explained by a sort of intelligent panspermia.
See http://en.memory-alpha.org/wiki/The_Chase_(episode) [memory-alpha.org]

Panspermia has a few big implications. If it's true, then we can't be 100% sure Earth ever had conditions that could create life (rather than just allowing the proliferation of existing life). It also has huge implications towards finding life elsewhere, such as on Mars, and maybe even future terraforming projects on distant worlds. The great thing about science is that we can find crazy ways to make the most ridiculous facts useful in developing new techniques or technologies, or towards creating models that help advance our knowledge in other areas.

Re:Millions of years of life-supporting conditions (5, Insightful)

femtobyte (710429) | about a year ago | (#45645913)

The problem that panspermia theories are supposed to "solve" is the ease or difficulty of "bootstrapping" life --- how likely is it to get self-replicating, self-organizing complex systems out of simpler chemical precursors. In the case that this is "really really unlikely," then panspermia allows the earliest forms of life to occur only in a few rare cases, but then spread to populate more of the universe. On the other hand, this is unnecessary if the initial chances of life formation are reasonable (given a few billion years and a planet-sized cauldron of random chemical soup). So far, scientists in the lab have been able to generate a lot of life precursors (amino acids, etc.) under "early Earth" conditions, but not demonstrate the "leap" to self-replicating systems; however, this may not prove too much, since scientists haven't had a billion years and a planet-sized petri dish array to try everything out.

Re:Millions of years of life-supporting conditions (4, Insightful)

symbolset (646467) | about a year ago | (#45646207)

Earth is pretty new as these things go. An 8 billion year head start is an awful lot.

And ... (1)

Anonymous Coward | about a year ago | (#45645489)

And I could have been born smart and good looking. But that didn't happen either.

Anthropic Principle (0)

Anonymous Coward | about a year ago | (#45645499)

I don't think the author completely understands what the Anthropic Principle is.

Re:Anthropic Principle (4, Informative)

boristhespider (1678416) | about a year ago | (#45645599)

With no offense to an AC on Slashdot, and acknowledging that I also do not agree with Loeb's conclusions in this paper (even describing some of it as "calculations" is stretching the word somewhat), I can confirm that Loeb is an extremely capable cosmologist who has contributed far more to science than I ever have (and, I would guess, than you ever have either - though obviously I might be wrong on that one) and than most people ever have. He's one of the people I'd say would understand the anthropic principle.

I'm not sure what he was intending to accomplish here, but in general his output is of the highest quality.

Re:Anthropic Principle (-1, Offtopic)

sporting go4 (3445497) | about a year ago | (#45646443)

that's a problem,I don't know what can we do.so I go4sporting yet

Re:Anthropic Principle (1)

sporting go4 (3445497) | about a year ago | (#45646511)

I agree with you

So Space Whales? (0)

Anonymous Coward | about a year ago | (#45645507)

So does this imply that it's plausible that life could have formed and subisuently evolved an extrmophile form that may still be roaming deep space?

Re:So Space Whales? (5, Informative)

HaeMaker (221642) | about a year ago | (#45645631)

No. Water is water at 300K at standard pressure. IN space, water is steam without pressure. You need gravity and an atmosphere to create pressure.

ah yes, a time when (4, Funny)

Bramlet Abercrombie (1435537) | about a year ago | (#45645519)

His vast Noodly Appendeges still bathed the entire cosmos is a fine tomato based sauce.

Begats Galore (1)

Tablizer (95088) | about a year ago | (#45645539)

That's a heck of a lot of "greats" in great great great great great..........great grandparent.

"I used to squirm to school barefooted in cosmic radiation and supernovas exploding in my protoplasm face every day!"

Panspermia? (1)

Anonymous Coward | about a year ago | (#45645551)

If this is true, the entire universe could have been seeded with life, or at least its precursors, almost from the very beginning.

not just planets (0)

Anonymous Coward | about a year ago | (#45645557)

It wouldn't have been just planets that were this warm. All the asteroids, comets, dust specs would have been this warm. If you look at evolution as time * volume, what was the volume here? Does this time * volume exceed all of Earth's history?

There's also the matter of energy. Just being warm enough to have water doesn't imply being able to run a heat pump. Don't know if chemicals are enough, or if you need a nearby sun. If you need a nearby sun, the Goldilocks epoch would be later than this calculation.

Duh.... (4, Funny)

Lumpy (12016) | about a year ago | (#45645569)

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

Re:Duh.... (0)

Anonymous Coward | about a year ago | (#45646117)

Pretty sure Time Lords were previous universe's humans that managed to survive past the universe's EOL.

Hence the whole spiel about reverting back to teh basic human form and the whole "you look human" "you look time lord" bit.

Re:Duh.... (0)

sporting go4 (3445497) | about a year ago | (#45646529)

windows 8 with my go4sporting,usually was distake,I very Angry

Fluidic Space (0)

Anonymous Coward | about a year ago | (#45645595)

So would this in theory have created a universe akin to fluidic space from ST:Voyager? LIke would the whole universe be composed of this? Or just clusters of matter of stars and planets like today?

Frankly i feel very stupid for asking this question and using that reference (always thought fluidic space was a dumb idea), but I admit in my non-astro-physicist mind this idea sounds compelling.

A long time ago.. (1)

Anonymous Coward | about a year ago | (#45645597)

in a far away Galaxy..

mod parent up! (0)

Anonymous Coward | about a year ago | (#45645909)


This is frightening (5, Interesting)

JoshuaZ (1134087) | about a year ago | (#45645605)

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.

Re:This is frightening (2)

roc97007 (608802) | about a year ago | (#45645665)

> 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 (1)

Anonymous Coward | about a year ago | (#45645729)

Well, no Dyson spheres. So what? Those and other conjectures about what signs an extremely advanced civilization might leave behind are just the weak guesses of a mob of relative insects (earthlings). Advanced civilizations may well have solutions and technology that we cannot even imagine. In fact, I think it unlikely that we would have any mental grasp of such advanced technology, as big a blow to our egos as that might be.

Re:This is frightening (1)

JoshuaZ (1134087) | about a year ago | (#45645767)

Doesn't work. It isn't just a lack of Dyson spheres. It is a complete lack of any signs of artificial structure, or of use of the vast amounts of energy available from stars. As far as we can tell, everything looks natural.

Re:This is frightening (4, Insightful)

Anonymous Coward | about a year ago | (#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?

arrogance of the humans (0)

Anonymous Coward | about a year ago | (#45645869)

The real paradox is why people still think we should look for impossible things.

The reality is .... things are what we never would have dreamt of. It's not looking for the impossbility - but looking for what actually exists - and that more than likely is something we have never thought of in our puny little simian brains.

Re:This is frightening (4, Insightful)

boristhespider (1678416) | about a year ago | (#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.

Re:This is frightening (1)

JoshuaZ (1134087) | about a year ago | (#45645983)

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://lesswrong.com/lw/j4/absurdity_heuristic_absurdity_bias/ [lesswrong.com] . As to stellar lifting, you could instead of just declaring your ignorance spend a few seconds Googling or looking at Wikipedia. See here: https://en.wikipedia.org/wiki/Stellar_uplift [wikipedia.org] . And no, you don't generally do stellar uplifting to your own home star (unless you are doing something to extend its lifespan which seems dubious). You'd do stellar uplifting and similar techniques to get useful mass out of stars that don't have habitable planets near them (at least if you were remotely ethical from a human standpoint).

Re:This is frightening (0)

Anonymous Coward | about a year ago | (#45645919)

We're not throwing an intergalactic kegger here.

Re:This is frightening (4, Informative)

JoshuaZ (1134087) | about a year ago | (#45645923)

, 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:This is frightening (1)

khallow (566160) | about a year ago | (#45645935)

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 buildings or other structures on Earth or nearby (say on the Moon) from extraterrestrials?

Re:This is frightening (0)

Anonymous Coward | about a year ago | (#45646143)

"Actually, it is. Dyson spheres for example are such a case. "

Show me one. Ah, I see. So when you say things like "Actually, it is", you're talking crap straight out of your ass.

"One doesn't build them out of a single shell, but rather out of a cloud of satellites."

Oh, one does! How interesting! Do you have this "one"'s phone number or Twitter? Or is it more fantasy-level crap straight from your ass?

Re:This is frightening (1)

Anonymous Coward | about a year ago | (#45646345)

I love science fiction as much as the next guy, possibly even more....but people's inability to distinguish reality from fiction is really irritating. Do you know how much material is required for such a construct?

"A spherical shell Dyson sphere in the Solar System with a radius of one astronomical unit, so that the interior surface would receive the same amount of sunlight as Earth does per unit solid angle, would have a surface area of approximately 28.1 Eha (Exa Hectare), or about 550 million times the surface area of Earth"

Let alone what would be required to keep that material stably orbiting?

It has to be worthwhile to do - there has to be a payoff. "Oh cool I'm a sci-fi geek" isn't enough.

Re:This is frightening (0)

Anonymous Coward | about a year ago | (#45646579)

"Also there's the matter of local structures. Why aren't there obvious buildings or other structures on Earth or nearby (say on the Moon) from extraterrestrials?"

Maybe there is and we just have spotted them yet (despite its size its still a tiny little blip on the surface) or we don't recognize what they are (Because our expectation of what a structure they might use is very different) or they had it there and a meteor obliterated it and we can't see the debris at a distance.

Re:This is frightening (0)

Anonymous Coward | about a year ago | (#45646525)

Not just this, but there is also the glaring fact that we do not know what causes life! To make such a claim of "it could take X years to get life" when we don't know what initially causes life is simply asinine. Make sure that you read about why the primordial soup experiment was bullshit before you bring that out as the answer.

Re:This is frightening (0)

Anonymous Coward | about a year ago | (#45645787)

Maybe the scariest thing is that Earth and humanity might be special? I'm an atheist (or at least someone who believes that IF there ever was a higher-order being/beings involved in the history of Earth, he/she/it/they sure as hell isn't around anymore), but what if there's something to intelligent design?

Now THAT'S a scary thought.

Re:This is frightening (1)

Tablizer (95088) | about a year ago | (#45645969)

Or "Intelligent Gardeners" who wipe out or "trim" civilization spacing to avoid messy conflicts (which probably otherwise end in the most advanced one wiping out or diluting the newer one, based on Earth history.)

Or maybe "UFO Theory" is correct, and the "zoo keepers" protect us from cosmic riff-raff and have done thinning or cloaking around us.

Re:This is frightening (0)

Anonymous Coward | about a year ago | (#45646591)

This is almost a troll (maybe it is, but I'm in a good mood). Reductio ad absurdum is not the answer to the question of "is there a creator/god" no matter what you atheists try to claim. Get a basic Philosophy book and start at page 1.

Re:This is frightening (2, Interesting)

Charliemopps (1157495) | about a year ago | (#45645813)

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?

Re:This is frightening (1)

JoshuaZ (1134087) | about a year ago | (#45645957)

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 be "obserd[sic] joke"- they are if possible, an extremely useful way of using a large amount of available energy.

Re:This is frightening (0)

Anonymous Coward | about a year ago | (#45646063)

It's possible we are looking for the wrong signals too.

They may not be using radio to communicate, but their starship engines and large construction products might produce huge amounts of RF interference as an unintended side effect.

Re:This is frightening (0)

Anonymous Coward | about a year ago | (#45646055)

Depends. We still use gun powder. That stuff has been in use for varies things for at least a thousand years. Marijuana has been used for thousands of years as well. They found some buried in a Chinese tomb dating back quite a while ago.

So we may still be using radio waves, depending on the application at hand. It may fall into a more obscure use but doesn't necessarily mean we won't use it.

Well known filter is currently active (5, Interesting)

Anonymous Coward | about a year ago | (#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:This is frightening (1)

Anonymous Coward | about a year ago | (#45645939)

Well, here's the thing. All life about 100 years after evolving enough to invent the radio, also invents compresion, cryptography, the phased-array antenna, and so forth. That means that while we were looking for an intergalactic broadcast of the 1936 Olympic Games, we were picking up only occasional blips of highly compressed and encrypted alien tentacle pr0ns, indistinguishable from background noise.

Re:This is frightening (2)

wisnoskij (1206448) | about a year ago | (#45645967)

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 tens of thousands of years is more reasonable. Not that a few hundred is not plausible, but that 10K is plausible as well.

Re:This is frightening (1)

symbolset (646467) | about a year ago | (#45646243)

It should be easy enough to see ion engines or direct thermal thrust engines.

Re:This is frightening (0)

Anonymous Coward | about a year ago | (#45646371)

Which would explain the quiet. And given that civilizations tend to last only 1,000 years or so, that would never be enough time.
Or,you could say that it's only our chimp civilizations that have such limited spans. And that our chimp governments have been hiding/forced to hide the knowledge of ET's existence. That we'venever been alone, and space is swarming with the signatures of life, we ordinary slaves just aren't privy to it. The latter makes ore sense funnily enough.

Re:This is frightening (0)

Anonymous Coward | about a year ago | (#45646031)

How about running out of easily-extracted, affordable natural resources before you make it off the planet and never getting another chance at it? How about the society, stabilized at some reasonable comfort level, becoming so risk-averse that exploration is no longer mentally conceivable? We're approaching both of those even if nothing goes catastrophically wrong. Our current generation has lost interest in the universe, and humanity expanding into space is now further away from reality than it was 50 years ago. When considering the future, the best minds are concerned with maintaining our lifestyle with dwindling resources and see moon/Mars colonies as a wasteful luxury. Now, magical technology could come out of the left field and change everything, but this is something that can't be planned. The longer we wait in absence of it, the fewer resources we will have to dedicate to research or "breaking out". A permanent status quo will become more optimized over time until mankind is subsisting at the exact capacity that Earth can provide indefinitely, with no energy used for anything except survival at a static population level.

Re:This is frightening (0)

Anonymous Coward | about a year ago | (#45646053)

Because we:

a) lack the necessary specific tech to detect such a precise thing like another civilization

b) aren't smart enough to see it (see *a*)

c) we're in a wrong spot in the galaxy/universe. It's a big place. Get over yourself, we're only human and not that good.

Re:This is frightening (0)

Anonymous Coward | about a year ago | (#45646501)

There's really no surprise that we can't pick up any meaningful radio transmissions - the power dissipation makes it useless at stellar distances.

At a distance of 1 light-year, a 10 petawatt radio transmission is weakened to about 9 femtowatts; the CMB has an average power level of about 10 microwatts. At that distance the radio signal is slightly less than one trillionth of the power of the background radiation and is basically undetectable.

If we increase the radio transmitter's power output to 10 yottawatts, the signal still drops to about the same energy level as the CMB at one light-years' distance.

Based on the power generation stats I found on Wikipedia, that would use up a year's worth of all human power output in about 0.6 seconds.

Problem (1)

StripedCow (776465) | about a year ago | (#45645627)

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 square is, randomly, either black or white.

In some regions of the grid, you may see certain patterns. For example, in some pieces of this universe, you will see the complete work of Shakespeare written in Helvetica 16pt. (In other regions, you may see a dithered version of our beloved goatse picture.)

Now what is the probability of a 1,000x1,000 patch at a given position to be completely black? Well, 2^1,000,000, a rather big number. Any other pattern in that 1,000x1,000 patch would have the same probability. What is the average manhattan distance between such blocks? (Left as an exercise for the reader).

If, in this thought-experiment, a molecular structure that can bootstrap life corresponds to an NxN structure on a grid, you can compute the distance between these life-generators. And you will find rather large numbers.

The lesson is of course to keep those numbers in mind the next time you expect life on some planet with seemingly earthlike properties.

Re:Problem (1)

StripedCow (776465) | about a year ago | (#45645663)

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?

Re:Problem (1)

roc97007 (608802) | about a year ago | (#45645689)

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 (3, Interesting)

boristhespider (1678416) | about a year ago | (#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...

Re:Problem (0)

Anonymous Coward | about a year ago | (#45645791)

The problem with this reasoning is you are assume there is only one solution, we don't know how many solutions there are, also its not random, its driven by random mutations just as the flow of a river is driven by the random vibrations of the water molecules, the environment pushes back against the randomness in a non random way. To modify your analogy, each 1,000x1,000 patch would be flipping randomly through different combinations until a pattern was generated that the environment allowed to survive.

All I know (1)

onyxruby (118189) | about a year ago | (#45645645)

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.

Re:All I know (4, Informative)

femtobyte (710429) | about a year ago | (#45645799)

Evolution doesn't have an inevitable "upward" direction. Today's microbes are every bit as "evolved" as we are from Earth's first inhabitants. So far, humans are no more than an evolutionary blip --- perhaps one that briefly flourishes, then vanishes away with nary a trace. Given billions of more years, evolution may simply produce a differently-colored cockroach, rather than a transcendent race of super-beings.

Re:All I know (4, Funny)

140Mandak262Jamuna (970587) | about a year ago | (#45645825)

We just killed a 500 year old clam. Now you want to kill a 5 billion year old microbe? Just for the fun of studying it? Whats wrong with you?

Re:All I know (1)

140Mandak262Jamuna (970587) | about a year ago | (#45646391)

Those microbes are my ancestors, you insensitive clod!

Simple life perhaps... (1)

Anonymous Coward | about a year ago | (#45645651)

Although I find it unlikely given only several million years. Those planets have to cool.

Certainly not complex life, complex life requires a hell of a lot of time

How about water... now? (0)

Anonymous Coward | about a year ago | (#45645715)

My understanding is that as of very recently there was no scientific consensus on how Earth itself got its water... or so said a Discovery Channel presentation of the history of the Earth which otherwise seemed like mainline science (molten Earth, iced Earth, evolution, etc.).

Can someone offer an overview of the current hypothesis/consensus?

Just my opinion (1)

Adult film producer (866485) | about a year ago | (#45645749)

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 (5, Funny)

140Mandak262Jamuna (970587) | about a year ago | (#45645865)

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.

Re:Just my opinion (1)

Adult film producer (866485) | about a year ago | (#45645885)

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

Re:Just my opinion (0)

Anonymous Coward | about a year ago | (#45646225)

You should sue whoever's designing that.

Re:Just my opinion (1)

Bucc5062 (856482) | about a year ago | (#45645999)

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:Just my opinion (1)

140Mandak262Jamuna (970587) | about a year ago | (#45646273)

It was a very snarky posting there. I had chopped off the bottom that gave away the game. Sorry.

Re:Just my opinion (0)

Anonymous Coward | about a year ago | (#45646277)


I call hogwash (0)

Mister Liberty (769145) | about a year ago | (#45645805)

Even as recent as 165 years ago a temperature of '273 Kelvin' did not exist.

Too little time... (3, Insightful)

Evil Pete (73279) | about a year ago | (#45645835)

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:Too little time... (1, Informative)

Kuroji (990107) | about a year ago | (#45645961)

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 disregarding the rest; it's like saying that you have an oven that's heated up to 350 degrees, so there should be a cake in there, without putting any of the ingredients into the oven. Including a pan for the cake.

Re:Too little time... (0)

Anonymous Coward | about a year ago | (#45646513)

That's a pretty large assumption to make, given our knowledge of planetary formation was JUST turned on its ear earlier this month.

If a super-giant hydrogen star can form from the soup, so can a hydrogen rich gas giant. In the absence of a rocky neucleating core, an aggregating water droplet could also work if large enough, and rate of aggregation exceeded evaporation. There could we'll have been many "rogue" water and gas worlds lit by the CBR, and or, free floating in stellar nurseries, being lit by a combination of the CBR and the strongly reyliegh scattered light from the nearby ultramassive stars.

Warm and dark (4, Interesting)

FridayBob (619244) | about a year ago | (#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.

Re:Warm and dark (1)

Anonymous Coward | about a year ago | (#45646261)

That argument presupposes that photosynthetic life is necessary.
It isn't.

Autochemotrophic life is just as suitable, and more likely to rule the roost in such an environment, especially with hot, volcanically active cores inside such worlds coughing up energy rich mineral food supplies.

For panspermia to work, we don't need multicellular organisms. Single celled, but robust organisms work just as well.

Since the background radiation would be hot enough to keep water wet even in deep space, dense enough nebular gas clouds would present an ideal place. Being a stellar nursery, there would be light, being diffused though dense clouds of water vapor would make the light into a spread out luminous glow all over the place, and short on the life destroying UV spectra, while being moist and interspersed with other "heavy" particles from star deaths preceeding the formation of these nebulae.

Medium to large aggregations of warm water and dust would make excellent petri dishes. Remember, the universe was physically much smaller, and the vacuum of space much less vacuous.

Ambassador G'Kar (1)

RDW (41497) | about a year ago | (#45645933)

"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 they are, Miss Sakai, they walk near Sigma 957 and they must walk there alone."

Um, a random thought (1, Interesting)

50000BTU_barbecue (588132) | about a year ago | (#45645955)

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 the fabric of space to encourage life to form in atomic matter? Like the universe for them would have been the size of a watermelon and they'd have had energy at scales to make quasars look like a cheap eBay LED flashlight?

Re:Um, a random thought (0)

Anonymous Coward | about a year ago | (#45646137)

Sounds like the plot to a Stephen Baxter novel.

Re:Um, a random thought (1)

50000BTU_barbecue (588132) | about a year ago | (#45646191)

Maybe I need to update my library!

Re:Um, a random thought (0)

Anonymous Coward | about a year ago | (#45646219)

Reminded me of Dragon's Egg

Re:Um, a random thought (1)

50000BTU_barbecue (588132) | about a year ago | (#45646359)

Yeah, a bit of everything. Pohl's Gateway trilogy had the kulgelblitz energy creatures from the early universe trying their best to change the universe back to the early conditions. Dragon's Egg had the Cheela, overclocked living neutronium creatures.

Re:Um, a random thought (1)

femtobyte (710429) | about a year ago | (#45646229)

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, then you wouldn't be able to form sufficiently big/complex structures to do much before getting scrambled in the churning subatomic plasma. You'd need far "finer" structures, way way beyond the Planck scale, to "withstand the heat" and form interesting structures that could "do something" before being torn back apart. Such things can't be a-priori ruled out (we don't understand how physics works even at the Planck scale), but neither is there any reason to suspect such of existing (rather than whatever happens around the Planck scale being the "fundamental" level sufficient to generate the universe).

Grammar nazi (1)

Anonymous Coward | about a year ago | (#45646025)

It's "3 kelvins", not "3 Kelvin". Lower case to mean the temperature unit, upper case to mean 3 copies of Lord Kelvin.

Fringe "science" strikes again (0)

Anonymous Coward | about a year ago | (#45646035)

This is roughly like stating (with a straight face) that the Easter Bunny could have appeared 150 years after Santa Claus.

I don't care about ANY of your mythical "events" from history. Why the hell would I care about what one has to do with the other?

Were there even enough Heavy Elements at 15MY? (0)

StaticEngine (135635) | about a year ago | (#45646213)

I'm sure there was plenty of Hydrogen, and probably a lot of Helium at that point, but given that life (as we know it) depends on, at very least, elements up to Sodium (Atomic Number 11), and heaver elements are the result of nucleosynthesis in the exploding cores of dying stars, even with water around, were there enough heavier elements to support life? Was there even enough Oxygen around to form water, regardless of the temperature?

Intelligent life is based on metal... (0)

Anonymous Coward | about a year ago | (#45646259)

we are meat, they watch our TV shows and choose to ignore us.


Not much time (1)

hawguy (1600213) | about a year ago | (#45646263)

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.

Re:Not much time (2)

140Mandak262Jamuna (970587) | about a year ago | (#45646377)

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. Still it is difficult to believe multi celluar organisms could evolve that quickly.

Fluidic space (1)

wiredlogic (135348) | about a year ago | (#45646375)

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

Thermodynamics (1)

Michael Woodhams (112247) | about a year ago | (#45646381)

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 help from a star and planetary atmosphere to get liquid water, so a star's Goldilocks zone should be much larger than at present.

Re:Thermodynamics (1)

femtobyte (710429) | about a year ago | (#45646549)

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.

This would violate the Second Law (0)

Anonymous Coward | about a year ago | (#45646409)

Cosmologist argues that the Big Bang was at billions of degrees and the background radiation is barely above absolute zero. The temperature of the universe must have passed through the range at which water is liquid somewhere along the way. Therefore, Life could have evolved very early on.
Life continually becomes more organized. You are a lower-entropy state than a stew of hydrogen, carbon, etc. of the same mass and at the same temperature. Simply put, the number of microstates which are alive is much much less than the number of states which are aren’t. As soon as you die, your body starts to move towards one of those more likely configurations.
Life does NOT violate the Second Law of Thermodynamics because our decrease of entropy is more than compensated for by increases in entropy elsewhere. Specifically, in the Sun.
The Sun is more than a source of light and heat. Every quanta of energy which the Earth absorbs is, on average, radiated away again. If this were not so the Earth would grow steadily and indefinitely hotter (or colder.) What the Sun DOES is provide up for a steady supply of energy with low Entropy.
The Entropy of a body is, formally, its Energy divided by its absolute temperature. In the case of radiation, “temperature” is derived from its frequency. It’s the temperature of the body which emitted it. Every day Earth absorbs energy from a high-temperature source, about 6000 degrees. High temperature means low-entropy, because temperature appears in the denominator. The energy radiates back into space at Earth-temperature, about 60 F. So the Earth is continually throwing its unwanted Entropy into the night sky,
You need both a high-temperature source and a low-temperature sink to get anything useful done. A rock on a cliff above you does no work unless there’s a valley for it to fall into.
If the entire sky “glowed” at the same temperature the planet has, then Life would be unable to maintain its low-entropy state, to evolve or, indeed, to do much of anything.

Papa Bear and Mama Bear are People, Too (1)

retroworks (652802) | about a year ago | (#45646467)

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...

5mod down (-1)

Anonymous Coward | about a year ago | (#45646481)

long 7erm survival grandstanders, the
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