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A Lonely Universe

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Re: A Lonely Universe

#141

Post by foobarian »

pfdietz wrote: post #123
foobarian wrote: post #120

Earlier quoted context omitted.

> A super earth would require exponentially more Polynomially, right?

No, exponentially. I used that word precisely, because the mass ratio in the rocket equation is exponential in (delta V)/(exhaust velocity).

Thanks for the reply. Context: there are so few exponential processes in nature, especially around classical physics that it really stuck out here, so I made the comment. I should have searched and read up on it instead, but thought there is still some value in others seeing the conversation.

And lastly: that is really depressing :-(

Re: A Lonely Universe

#142

Post by me_me_me »

kerblang wrote: post #7

Dumb physics question: If a dying civilization 99,000 light years away sent its last radio transmission 100,000 years ago, we'd never know it happened, right? Maybe I'm missing something with those radio waves bouncing back and forth around us off of various big objects in the milky way.

there is a distance beyond which radio signal decays into background noise.

And even on the edge of it you are talking about enormous receivers to capture those transmissions.

When looking into scales of universe its truly staggering how vast distances we are talking about.

Re: A Lonely Universe

#143

Post by slothtrop »

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…

More than likely, we're early (as expansionist intelligent lifeforms go), and the race is still on to colonize.

Re: A Lonely Universe

#144

Post by me_me_me »

hoseja wrote: post #78
WalterBright wrote: post #74

We owe it to the universe to send out interstellar probes loaded with micro organisms to seed interesting planets. The notion that we have to sterilize all the interplanetary probes just so we don't "infect" other dead planets is just silly. We should have dropped a bag of life into Saturn's atmosphere, instead of a sterile probe.

Why? What will thousand years of delayed seeding do? It's very dumb to smear our poop onto other planets before we thoroughly investigate them.

> It's very dumb to smear our poop onto other planets

That is very clever way of putting it, looking at the state of our planet its 100% correct analogy. Thank you for making me chuckle.

Re: A Lonely Universe

#145

Post by pfdietz »

zabzonk wrote: post #140
pfdietz wrote: post #119

Earlier quoted context omitted.

But not because it needed too much energy.

Then for what other reasons?

Well, it needs electricity. For most of history, we didn't have electricity. And, we didn't have cheap electricity until electromagnetism was understood and electric power could be made from rotating machinery. After that, there needed to be found a chemistry that would allow aluminum to be made directly, rather than from sodium or potassium reducing aluminum compounds.

The actual physical amount of energy needed to make aluminum would have been available since forever; it's the form of that energy that wasn't there.

Re: A Lonely Universe

#146

Post by omnicognate »

rewgs wrote: post #98
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…

Yeah, I think that the Fermi Paradox can be pretty easily explained: the universe is fucking huge. Those who talk about the feasibility of alien life visiting us very simply haven't thought it through, or are ignorant of the reality of space. It's just too staggeringly big.

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 other side of our galaxy. Light travels really slowly on astronomical scales.

2. A supernova goes off roughly once every 50 years in the milky way. That's an energy release that is utterly incomprehensible to a human being. A system-incinerating catastrophe briefly producing an energy output comparable to that of all the stars in the galaxy combined. But to us they appear as just brighter-than-usual dots in the sky. We (humans) have only noticed a handful of them. It's not that we're shielded from them. These events happen in direct line of sight. They're just insanely far way and light intensity falls off with the square of distance. The kinds of energy outputs produced by a species of comparable technology to our own are simply not visible to us over these kinds of distances, even with the very latest technology.

And that's just our galaxy. If you consider the entire universe the things happening in direct line of sight include billion-solar-mass supermassive black hole mergers, and you need a gravitational wave detector to even tell they're happening.

We've only just recently started to be able to detect the presence of planets around other stars. The Fermi Paradox, Great Filter, "Where's the intelligent life?" stuff is absurdly premature.

Re: A Lonely Universe

#147

Post by me_me_me »

i386 wrote: post #106
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 happen…

If you start looking into definition of life itself you end-up deep into philosophical weeds, and start debating life like crystals, that dont feel alive but act as if they are biological organisms[0].

Heck even closer, is virus alive or its just a random runaway mutation of organic code?

I don't think life is rare, but self aware intelligence probably is exceedingly rare, given how expensive it is in terms of energy cost, and the balance of disadvantageous environment needed for it to emerge and survive but not enough to destroy it.

There are organisms that haven't evolved intelligence for millions of years because they are good enough to survive and not to mention the self awareness.

[0] https://www.wired.com/2013/01/living-crystal/

Re: A Lonely Universe

#148

Post by GoblinSlayer »

lubujackson wrote: post #24
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…

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…

Also light is very slow. The Arecibo Message was sent in 1974, it's now 48 light years away, which is tiny.

Re: A Lonely Universe

#149

Post by echelon »

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…

Maybe we're a simulation of an advanced alien intelligence in preparation for war games?

Maybe we're a simulation of future earth historians?

Maybe they're already here? A computational foam that surrounds us.

Maybe we're the first? Or life is exceedingly rare?

Maybe it's up there, purposefully undetected, killing anything that emerges? Like a spider in wait.

Maybe we've been seeded by them, and they're watching us grow?

Maybe physics breaking shenanigans and things we can't even model or understand are happening?

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