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A Lonely Universe

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Re: A Lonely Universe

#101

Post by wruza »

lhorie wrote: post #56
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…

Why are we assuming that we would be able to see intelligent alien life by just looking at the right spot in space? If we take it at face value the figure that the universe is 13 billion years old, and that the observable universe is 90 billion light years wide, presumably that means that there's a whole lot of universe that could have evolved intelligent life at a pace similar to our own, but that we just can't see…

Our evolution was not a straight line. We could stay in bacterial form for a couple of billion years if not the great oxygenation event, or have a couple of billions of years of advantage if it happened that earlier. The evolution from simple marine life to us happened in an instant compared to pre-O2 era.

https://www.shutterstock.com/ru/image-vector/evolution-life-...

Re: A Lonely Universe

#102

Post by rewgs »

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…

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?

Re: A Lonely Universe

#103

Post by vbezhenar »

thrashh wrote: post #44
lubujackson wrote: post #24

Earlier quoted context omitted.

The third option is that everything is simply too far apart and any detectible transmissions are either too faint or buried behind all those massive fusion furnaces. For instance, if our best Earth tech was pointed at Earth from a distant star, how far away would we be able to detect our own traces of life? We know that life is "a little rare" at least, but there is a huge range of rarity where life is everywhere acr…

Another possibility is that energy is really hard to come by. Humans absolutely struggle to amass much energy. Think of the insane amount of energy required to lift things into space, and how many millions more amounts of energy we’ll need just to build something in space. Heck if you go drive off grid on Earth, you can barely bring any energy with you and you won’t really be able to generate an appreciative amount o…

That's why it makes no sense to build something big by lifting heavy things from the Earth. Just mine asteroids, extract iron, melt it into chunks, then transport those chunks very slowly but with huge throughput from asteroids to the necessary building site in space and use them to build space ship. You can melt iron just by focusing enough sun light and you can build ships closer to sun for cheaper sun light. It's imaginable with current technologies, we just need industry to move into space.

Imagine that with all your knowledge you suddenly moved to the ancient times. You know how to make CPU but you can't even make a shovel because iron production is not there. You need to spend enormous amount of time and efforts to build all the industries required to build a factory to produce simple resistor. That's where we at when it comes to space right now. We need to spend lots of time and effort to build space industry. But once it's there, space ships will not be a big deal.

Re: A Lonely Universe

#104

Post by ncmncm »

Scarblac wrote: post #88
api wrote: post #37

Earlier quoted context omitted.

Theoretically if you could travel very close to the speed of light time dilation would make the trip fairly short. Of course it’s one way since it would take hundreds of thousands to millions of years for everyone else. If you came back you would be returning to a different geological epoch. Of course the energy requirements are insane and would require some kind of physicists nightmare propulsion system like antimat…

> Of course the energy requirements are insane and would require some kind of physicists nightmare propulsion system like antimatter rockets. Lose reactor containment and you are instantly converted into plasma and gamma rays. If you hit something the size of a dust particle it will destroy your spacecraft. And, this one spacecraft needs to be able to slow down, have the telescopes and equipment needed to identify ex…

Maybe count on somebody where you are going to help you slow down? They will see you coming a hundred thousand years ahead of time. They might decide it is safer to just park a planet in your way, though.

So for, what, two million years or five, the front of your spaceship is blasted with near-lightspeed intergalactic-medium molecules, plus trillions of dust particles and an unknown number of rocks.

"Erosion" is not an adequate word, but we don't have any that is.

Re: A Lonely Universe

#105

Post by ncmncm »

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…

Rocky planets are for only the most extreme primitives. If anybody noticed us at all, they wouldn't have any interest in talking. They might probe us. Maybe copy somebody into a simulator that works a million times faster, and quiz that, instead?

All the action is out in the Kuiper belts, where there is abundant cold, which is more valuable than any material substance.

Re: A Lonely Universe

#106

Post by i386 »

frazbin wrote: post #16

Fun! But if abiogenesis happened more than once, and we don't see any alternate-root lineages, then we've admitted the possibility that major advances towards complex life can have a resource lock out effect leading to the extinction of alternates; this could apply to any or all of the critical steps towards technological intelligence. e.g. did the evolution of homo sapiens and its subsequent monopolization of earth…

> e.g. did the evolution of homo sapiens and its subsequent monopolization of earth resources decrease the chances of another intelligent species evolving? Probably.

Only if you assume that intelligent life fills an ecological niche. As far as I am aware that’s some hot debate in evolutionary biologist circles.

There’s a strong chance this is all a massive fluke, given the configuration of our solar system and happenstance of earths position and chemical makeup.

Then again we wouldn’t be around to observe what we see today if it wasn’t for all those things aligning.

As observations of extra solar systems increase, I’m more inclined to think life is rarer and intelligence is exceedingly more rare.

Nothing wrong with an empty universe. Less to contend with.

Re: A Lonely Universe

#107

Post by [deleted] »

rewgs wrote: post #102
fleddr wrote: post #15

Earlier quoted context omitted.

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…

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?

[deleted]

Re: A Lonely Universe

#108

Post by ncmncm »

TheOtherHobbes wrote: post #32
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…

Or maybe Von Neumann machines can't be built because they're impractical. Consider that you need an AI that can deal with a huge range of potential environments, build extraction, processing, and assembly machinery, and do all of this with perfect error correction and oversight. Pretty much eternally. It's an interesting thought experiment. But as a practical engineering project, it really doesn't sound even remotely…

You understand that we, personally, are von Neumann machines? Not very well-tuned ones, because we happened by accident. Bacteria did, too, and are more efficient, just limited in scope.

So, we have proof it is possible; it only needs refinement.

Re: A Lonely Universe

#109

Post by TheRealNGenius »

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…

You make hypothetical scenarios sound like presupposed fact. You don't know that life is rare or that something else happens to make it appear as such. There are multiple alternative scenarios that you haven't considered amongst the vast sea of possibilities. That you suppose thusly is indicative of your lack of imagination.

Re: A Lonely Universe

#110

Post by TheRealNGenius »

UncleOxidant wrote: post #25
api wrote: post #12

Earlier quoted context omitted.

I think this is likely. Always remember that intergalactic travel is exponentially harder than interstellar travel and that is already brutally hard. We need only be among the first in our galaxy to explain the Fermi paradox.

I don't see how there could ever be intergalactic travel.

much akin to how cavemen couldn't fathom how they could possibly talk to another caveman on the other side of the earth.
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