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Once we can see them, it’s too late

scottaaronson.com

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Re: Once we can see them, it’s too late

#22
post #6

Hubrisimus. Our current models are the most useful ones we have that fit our limited dataset, but we have no clue whether we understand the first thing about space and time and the age and size of the universe(s).

What's the alternative to working with the data you have?

Re: Once we can see them, it’s too late

#23
An interesting paper that I don't see brought up often enough is "Dissolving the Fermi Paradox" by Anders Sandberg, Eric Drexler and Toby Ord[0]. They show that it isn't a surprise that we are alone in the universe if we consider the uncertainty inherent to parameters of the Drake equation. Their analysis estimate that there is (at least) a 39% chance that we are alone in the observable universe.

[0]: https://arxiv.org/abs/1806.02404

Re: Once we can see them, it’s too late

#24
post #6

Hubrisimus. Our current models are the most useful ones we have that fit our limited dataset, but we have no clue whether we understand the first thing about space and time and the age and size of the universe(s).

What's the alternative to working with the data you have?

There is no alternative to working with the data you have.

But believing that you understand the data when there are huge glaring inconsistencies in your understanding is... naive.

Re: Once we can see them, it’s too late

#25
It seems like the argument gets a lot less interesting if the most-expanding interstellar civilizations don't spread at anywhere near the speed of light?

It's easy to think of reasons why this might be the case. There is acceleration, deceleration, and replication time, which seems like it would be substantial for any civilization that doesn't want to put most of its resources into replicating as fast as possible.

Re: Once we can see them, it’s too late

#26

Earlier quoted context omitted.

What's the alternative to working with the data you have?

There is no alternative to working with the data you have. But believing that you understand the data when there are huge glaring inconsistencies in your understanding is... naive.

I guess I missed the part where this was proclaimed to be Truth.

Re: Once we can see them, it’s too late

#27

This seems like a variant of a hypothesis I've heard before: "The universe is old enough, and the rate of expansion of a spacefaring civilization is fast enough (relative to the age of the universe, even at sub-light speeds) that either the aliens should already be here since long ago, or we're the first (or among the first)." ?

What makes you think we'll be among the first?

No human being has ever set foot on a different planet.

No man-made object has ever reached a star system outside our own, let alone landed on a planet.

We may still be quite a long way away from accomplishing those things at scale.

Re: Once we can see them, it’s too late

#30

How a civilization would expand at the speed of light? Unless it lives directly on the fabric of space or something like that, matter is discrete in the universe. You settle on planets that are not everywhere, or in space stations built with Oort cloud or asteroid belts materials, but it takes time to settle and expand in each new ground you get. You are not talking about the speed of light anymore there. Of course,…

Think “matter scanner/printer”.

Scan an object, at atomic & energy vector level. Transmit that information to a destination’s printer. Expansion is then indeed at speed of light, capped only by need to physically move a small “seed” printer (rapid transport may have enormous energy cost, but that’s all that needs moving; everything else is just data).

Having seen tech go from digital imaging to 3D organ printing in a fraction of my lifespan, seems plausible.

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