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Space Is Full of Planets, and Most of Them Don't Even Have Stars

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Re: Space Is Full of Planets, and Most of Them Don't Even Have Stars

#111

Post by maaark »

Aaargh20318 wrote: post #102
m_mueller wrote: post #91

Earlier quoted context omitted.

What about Fermi's paradox though? I mean, where is everyone?

Personally I think the answer is anti-natalism. Once life gets more intelligent it takes a relatively short time (compared to the age of the universe) to get to the point where they realise it's unethical to create new life and choose to go extinct. As a result, intelligent life around the universe only exists as short 'blips', being around for too short a time to ever meet other species.

>it's unethical to create new life and choose to go extinct.

I don't get this. What use are ethics when everyones dead and gone?

Re: Space Is Full of Planets, and Most of Them Don't Even Have Stars

#112

Post by throwaway7312 »

m_mueller wrote: post #91
hyperpallium wrote: post #75

Earlier quoted context omitted.

If you're a fan of Moore's Law and the Singularity, you'll love the reasoning of backtrapolating the exponentially increasing complexity of life over time... to get 0 well before the formation of the earth https://www.technologyreview.com/s/513781/moores-law-and-the...

What about Fermi's paradox though? I mean, where is everyone?

Uncontacted tribes in the Amazon likely wonder the same thing. It's such a big Earth, yet only a few hundred humans are known to exist.

Why are there no other detectable signs of human life, like smoke signals, territory markers, or emissaries from any more but a handful of other tribes? Surely if advanced humans existed, they would have contacted these tribes by now, to share technology, discoveries, and medicine. Yet they haven't.

How can the whole planet be so... silent?

Re: Space Is Full of Planets, and Most of Them Don't Even Have Stars

#113

Post by pavlov »

Aaargh20318 wrote: post #102
m_mueller wrote: post #91

Earlier quoted context omitted.

What about Fermi's paradox though? I mean, where is everyone?

Personally I think the answer is anti-natalism. Once life gets more intelligent it takes a relatively short time (compared to the age of the universe) to get to the point where they realise it's unethical to create new life and choose to go extinct. As a result, intelligent life around the universe only exists as short 'blips', being around for too short a time to ever meet other species.

The default for unintelligent life is to survive at all cost and fill every niche. You're suggesting that intelligence flips that purpose so that every sentient species eventually becomes depressed suicidal existentialists?

Re: Space Is Full of Planets, and Most of Them Don't Even Have Stars

#114

Post by hvidgaard »

leonroy wrote: post #80
hvidgaard wrote: post #78

Earlier quoted context omitted.

That is actually scary. When you travel in interstellar space, you can only travel in directions where you can see light at all times.

Which actually becomes a problem in the far future when stars have moved further away from each other in an ever expanding universe and their light output becomes increasingly dim to a space faring traveller...

When I think about it, maybe it isn't a problem after all. I would think that you can measure gravity and see black holes before you hit them.

Re: Space Is Full of Planets, and Most of Them Don't Even Have Stars

#115

Post by ben_w »

cobbzilla wrote: post #88
ben_w wrote: post #69

Earlier quoted context omitted.

The extra mass of the planet would increase the rate of fusion. https://what-if.xkcd.com/14/

to a point you are right, but clearly there is some boundary, right? imagine a solid object with a mass just below the Chandrasekhar limit and a temperature near absolute zero. Don't tell me hurtling that into the Sun will make it burn hotter. And even if it would (or a smaller object) in the long run, there would at least be some period of time before the incoming matter reached fusionable temperatures, reducing pow…

I think you just described what happens to a stellar core during a supernova. The temperature difference between the surface and core of a red giant is so large the surface might as well be “near absolute zero”.

Re: Space Is Full of Planets, and Most of Them Don't Even Have Stars

#116

Post by throwaway7312 »

Aaargh20318 wrote: post #102
m_mueller wrote: post #91

Earlier quoted context omitted.

What about Fermi's paradox though? I mean, where is everyone?

Personally I think the answer is anti-natalism. Once life gets more intelligent it takes a relatively short time (compared to the age of the universe) to get to the point where they realise it's unethical to create new life and choose to go extinct. As a result, intelligent life around the universe only exists as short 'blips', being around for too short a time to ever meet other species.

It sounds more like anti-natalism is your personal philosophy, and you make the same assumption the holders of most philosophical, ideological, and religious positions make: sooner or later, everyone else will realize to be true what I realize is true.

The history of man suggests otherwise. The more our civilization progresses, and the more the population swells, the broader the array of philosophical positions those within the civilization tend to hold. We have no evidence for everyone eventually coalescing around one 'right' belief set.

History is also littered with non-reproductive sects, like the Essenes, aesthetics, or, today's answer to these, anti-natalists and child-free individuals. These groups don't tend to be very good at passing their belief systems on to new generations however, as one might expect, and they don't tend to last particularly long once they've emerged on the civilization scene.

Re: Space Is Full of Planets, and Most of Them Don't Even Have Stars

#117

Post by zaarn »

hvidgaard wrote: post #114
leonroy wrote: post #80

Earlier quoted context omitted.

Which actually becomes a problem in the far future when stars have moved further away from each other in an ever expanding universe and their light output becomes increasingly dim to a space faring traveller...

When I think about it, maybe it isn't a problem after all. I would think that you can measure gravity and see black holes before you hit them.

Measuring gravity is hard. What you can do is measure gravity at both ends of your ship and if they differ by a lot you're currently being shredded apart by a blackhole.

Re: Space Is Full of Planets, and Most of Them Don't Even Have Stars

#118

Post by chongli »

throwaway7312 wrote: post #112
m_mueller wrote: post #91

Earlier quoted context omitted.

What about Fermi's paradox though? I mean, where is everyone?

Uncontacted tribes in the Amazon likely wonder the same thing. It's such a big Earth, yet only a few hundred humans are known to exist. Why are there no other detectable signs of human life, like smoke signals, territory markers, or emissaries from any more but a handful of other tribes? Surely if advanced humans existed, they would have contacted these tribes by now, to share technology, discoveries, and medicine. Y…

If they're not aware of any other humans (let alone all the cities out there) then they're likely not aware of the actual size of the earth. Perhaps they only consider it in terms of the surrounding territory.

Re: Space Is Full of Planets, and Most of Them Don't Even Have Stars

#119

Post by RobertoG »

m_mueller wrote: post #91
hyperpallium wrote: post #75

Earlier quoted context omitted.

If you're a fan of Moore's Law and the Singularity, you'll love the reasoning of backtrapolating the exponentially increasing complexity of life over time... to get 0 well before the formation of the earth https://www.technologyreview.com/s/513781/moores-law-and-the...

What about Fermi's paradox though? I mean, where is everyone?

A main component of the paradox is time, but this paper solve that. Life existed from the beginning, but only now has become complex enough.

So, we don't see or hear artificial signs in other galaxies because light is from the times when there was not complex life in the universe.

Now, we only have to solve why we don't see or hear artificial signs in our galaxy. But the problem is not so perplexing because we are talking about one or two million years.

If, for instance, a big part of the galaxy is bad for complex life (after all, we are far away from the center and that could be relevant), Fermi's paradox is solved.

Re: Space Is Full of Planets, and Most of Them Don't Even Have Stars

#120

Post by smichel17 »

lucb1e wrote: post #92
simonh wrote: post #61

Earlier quoted context omitted.

The trouble is you'd need to stop, mine the mass, then accelerate back up again. If you have the fuel to stop to refuel in the first place, you don't need to stop refuel, unless there's something else you need as well.

I think that's what your parent meant with "if the delta v is favorable", like, if you move in the same direction and the speed difference isn't too absurd, it might be worth mining there.

Naive comment here, but wouldn't it be highly unlikely to encounter such a planet given your low relative velocity to it?
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