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A Lonely Universe

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Re: A Lonely Universe

#161

Post by GoblinSlayer »

rel2thr wrote: post #124
Causality1 wrote: post #2

Either intelligent life is rare in the universe or there's something that happens to it that prevents it from what we envision as the future of our own species, i.e., colonizing and spreading among planets. Maybe 99.99% of species ruin their own climate before getting off-world. Maybe they all decide it's happier living as hunter-gatherers. Unless we're alone, there is some fate that's common to all intelligences and…

It’s pretty rare on earth too, 10 million species but only 1 has space flight and the others aren’t anywhere close to developing it!

We had neanderthals.

Re: A Lonely Universe

#162

Post by pharke »

TheOtherHobbes wrote: post #38
mongol wrote: post #6

Earlier quoted context omitted.

Is it not possible that colonizing a galaxy is simply too hard, no matter what intelligence?

Or it's so easy. Ants live in cities surrounded by humans, but have no idea what a human is or what humans do, and literally cannot experience - never mind imagine - what a human is, what a city is, what transport networks are, what culture is, what technology is. Every so often an ant nest is destroyed because it's an irritant, but if the ants notice at all they carry on relatively unthinkingly. There are only other…

I think the Arthur C Clarke quote "Any sufficiently advanced technology is indistinguishable from magic" should perhaps be amended to "Any sufficiently advanced technology is indistinguishable from nature" it doesn't quite have the same ring to it but it's probably more truthful, at least for very, very, very advanced technology.

Re: A Lonely Universe

#163

Post by omnicognate »

WillPostForFood wrote: post #152
omnicognate wrote: post #146

Earlier quoted context omitted.

Yep, the Fermi "paradox" is no paradox at all. We have basically no evidence that life (including intelligent life) isn't common yet. There are so many ways to think of how big our galaxy is but two are particularly relevant to how difficult it would be to detect other life, or be detected: 1. The first radio signals the human race produced have so far travelled something like a thousandth of the distance to the othe…

is absurdly premature. Only relative to our own existence. If the universe is ~14 billion years old, and life was plentiful, you might expect life to have emerged elsewhere hundreds of millions or a few billion years before us. That allows for enough time for signals to have reached earth, even at slow light speeds.

That part was more about us being detected by others, really. The portion of the galaxy within which aliens could theoretically have noticed us since we developed radio technology and responded in a way we could have noticed by now is tiny.

As far as us noticing other civilisations is concerned the second point is the major one: the signals involved would just be really, really tiny. The "prematureness" is relative to our development of technology that could detect them.

You can of course posit that really advanced civilisations would produce massive energy signatures but I'm not sure that makes sense. The visible night time glow our planet produces due to our presence is a signature of inefficiency and light pollution. I'd hope that with better technology and politics we could make our planet look dark again from space. Efficiency, lack of wasted energy seems at least as likely to be a hallmark of a very advanced civilisation as huge, catastrophic energy releases. And even if those energy releases exist and really are spectacularly huge they'd still be massively hard to spot.

Re: A Lonely Universe

#164

Post by 7thaccount »

TheRealNGenius wrote: post #111
edgyquant wrote: post #75

Earlier quoted context omitted.

What’s the difference?

that one can't discern the difference, yet would undergo this procedure themselves, is telling in and of itself

Can you elaborate? I think sharding yourself (breaking yourself into clones, not pooping on yourself) would be pretty interesting. A lot of problems could be worked on simultaneously. There are of course philosophical implications. I think it is fine as long as it isn't forced.

Re: A Lonely Universe

#165

Post by rewgs »

ncmncm wrote: post #114
rewgs wrote: post #102

Earlier quoted context omitted.

It's very late and I don't have the energy to look up the math, but: Assuming you're traveling at light speed across the Milky Way, a distance of 100,000 light years, the trip would take 100,000 years for the person traveling, no? I wonder then how long it would be for everyone left on Earth. Millions of years?

No. The closer you get to light speed, the less time it seems to you to take getting there. If you could get close to light speed, "only" 100,000+ years would pass back home, never less, but could be any larger amount. At 1/10 light speed, a million years pass back home and almost a million on board. If you don't get really, really close to light speed, it still takes thousands of years, on board. Getting close takes…

So, even though “100,000 light years” means “it will take 100,000 years to travel this distance at the speed of light,” those traveling won’t experience it as 100,000 years, but rather a much shorter time period? How long would the travelers experience that as?

To be clear I’m not talking about “almost light speed,” I’m talking about traveling at exactly the speed of light (ignoring for a moment whether that’s possible).

Re: A Lonely Universe

#166

Post by loa_in_ »

I know "it's never aliens", and proof is required first, but I personally believe, deducing in a Holmes-like fashion (after you remove the impossible only the truth remains) that what we're seeing is consistent with us being the first ones around. I think we're the ancients. Maybe life is easy but first to arise will be extremely confused.

Re: A Lonely Universe

#167

Post by citizenpaul »

I'm a fan of the early universe explanation. Even by our most modest estimates from what we know we are likely in the very early like Also I find the drake equastion estimates to be incredibly generous in most places that it is used. It often has very high estimates for inhabitable planets. Since we only know of one such planet anything over zero in that equation is basically wild speculation. Once you put one or zero for average inhabitable planets the drake equation gets depressing.

Re: A Lonely Universe

#168

Post by ncmncm »

rewgs wrote: post #165
ncmncm wrote: post #114

Earlier quoted context omitted.

No. The closer you get to light speed, the less time it seems to you to take getting there. If you could get close to light speed, "only" 100,000+ years would pass back home, never less, but could be any larger amount. At 1/10 light speed, a million years pass back home and almost a million on board. If you don't get really, really close to light speed, it still takes thousands of years, on board. Getting close takes…

So, even though “100,000 light years” means “it will take 100,000 years to travel this distance at the speed of light,” those traveling won’t experience it as 100,000 years, but rather a much shorter time period? How long would the travelers experience that as? To be clear I’m not talking about “almost light speed,” I’m talking about traveling at exactly the speed of light (ignoring for a moment whether that’s possib…

At exactly the speed of light you would experience no duration at all. But it would take infinite energy to get going that fast, and infinite energy again to stop, and would still take 100,000 years as seen by anybody watching at either end.

Re: A Lonely Universe

#169

Post by pharke »

fleddr wrote: post #15
mongol wrote: post #6

Earlier quoted context omitted.

Is it not possible that colonizing a galaxy is simply too hard, no matter what intelligence?

Exactly. For an optimist, we might one day colonize Mars. Next, getting out of our solar system is incredibly unlikely as the first habitable destination in our own galaxy is just so far away. Say we stretch our optimism and do make it. Now the colonization of the Milky Way starts. It's a 100,000 light years to the other end. You'd be a completely different species by the time you arrive. Say you achieve that (you wo…

I don't think we will remain as is but I also don't think we will never leave the solar system. Everyone seems to miss the next great technological advance that's currently under way. Biology as a practical science is still in its infancy. We haven't yet learned to fully control the cell and its many forms and functions but I don't doubt that we will given enough time. Once we do, there is no reason we could not adapt fully to space travel.

Re: A Lonely Universe

#170

Post by pharke »

The main point of the article seems to be that because we are the only branch of life on our planet that became multicellular and started reproducing sexually that it is unlikely that this ever happens. I think that neglects the possibility that once multicellular life arises and begins the arms race of competing with other multicellular lifeforms as well as single celled life, it quickly gets to the point where it can easily outcompete any newly multicellular life. In other words, perhaps the precondition for the development of multicellular life is the absence of other multicellular life.
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