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Comment by glbrew | Hacker News Reader

Now I'm sad

Over the billions of years this will take humanity's descendants will probably figure out how to create whatever universes they want

Don't worry, we will collide with Andromeda before our Sun will die. So at least one other Galaxy can be "explored".

Or really, any of the about 50 galaxies in our local group.

If we could travel at light speed that is, which we can't and likely never will.

On the bright side, we'll probably never explore much of our galaxy, let alone the universe at large.

that just makes it worse...

This might help

http://www.thrivenotes.com/the-last-question/

I'm pretty convinced we will either die out or fill the galaxy with people. If we can start the reaction by going one other place and inhabiting it I think it will ultimately set off a chain reaction. Lots of work to do between now and then but it seems like its mostly engineering now vs new discoveries.

> Lots of work to do between now and then but it seems like its mostly engineering now vs new discoveries.

I'm not sure what you mean by this. There are still lots of issues with just surviving the journey, let alone making a foreign planet habitable and establishing a society. We need lots more discoveries in energy and understanding human physiology before it becomes just an engineering problem.

Beyond the reachability limit, there's something even sadder, but possibly even more poetic: the comoving future visibility limit. That's the surface beyond which, although matter may exist, light from it will never reach us. In terms of time, it's very, very early - before the luminous phase of the big bang which gives us the cosmic microwave background.

It's the very last thing on the map of the universe:

http://www.astro.princeton.edu/universe/

There is actually a whole sequence of such limits: the visibility limit (where light emitted in the distant past reaches us now) is furthest out, then comes the reachability limit (where light emitted by us now can still be observed), then the round trip limit where we can send a message now and recieve an answer (before we are beyond their reachability limit), then the limit where we can send a message, recieve an answer and then send a final goodbye, then the limit for two full exchanges, and so on...

But at least one could do the respective trips to slightly closer galaxies within a lifetime: http://arxiv.org/pdf/astro-ph/0509268.pdf (published in Phys.Rev. D, http://journals.aps.org/prd/abstract/10.1103/PhysRevD.72.107... )

I always get half-sad half-glad when I read these types of things.

Glad that I won't have to see this depressing end to the universe but still sad for humanity, that we won't last forever.

I don't know about you but I plan on lasting forever.

But barring that, I'd settle for a couple thousand years.

Same for me, I hope I am among the 6.5% of humans who don't die[0]!

[0] https://en.wikipedia.org/wiki/World_population#Number_of_hum...

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