Comment by exfalso
3 days ago
There's a fun hypothesis I've read about somewhere, goes something like this:
As the universe expands the gap between galaxies widens until they start "disappearing" as no information can travel anymore between them. Therefore, if we assume that intelligent lifeforms exist out there, it is likely that these will slowly converge to the place in the universe with the highest mass density for survival. IIRC we even know approximately where this is.
This means a sort of "grand meeting of alien advanced cultures" before the heat death. Which in turn also means that previously uncollided UUIDs may start to collide.
Those damned Vogons thrashing all our stats with their gazillion documents. Why do they have a UUID for each xml tag??
It is counter intuitive but information can still travel between places that are so distant that expansion between them is faster than the speed of light. It's just extremely slow (so I still vote for going to the party at the highest density place).
We do see light from galaxies that are receding away from us faster than c. At first the photons going in our direction are moving away from us but as the universe expands over time at some point they find themselves in a region of space that is no longer receding faster than c, and they start approaching.
That's not exactly it. Light gets redshifted instead of slowing down, because light will be measured to be the same speed in all frames of reference. So even though we can't actually observe it yet, light traveling towards us still moves at c.
It's a different story entirely for matter. Causal and reachable are two different things.
Regardless, such extreme redshifting would make communication virtually impossible - but maybe the folks at Blargon 5 have that figured out.
I think I missed something: how do galaxies getting further away (divergence) imply that intelligent species will converge anywhere? It isn’t like one galaxy getting out of range of another on the other side of the universe is going to affect things in a meaningful way…
A galaxy has enough resources to be self-reliant, there’s no need for a species to escape one that is getting too far away from another one.
You'll run out of resources eventually. Moving to the place with the most mass gives you the most time before you run out.
Yes that's the idea. The expansion simply means that the window of migration will close. Once it's closed, your galaxy is cut off and will run out of fuel sooner than the high-density area.
Well eventually there are no galaxies just a bunch of cosmic rays. Some clusters of matter will last longer.
I think for this to work, either life would have to plentiful near the end, or you’d need FTL travel.
Social aspect. There is no need but it's more fun to spend the end of the Universe with other intelligences than each in its own place.
I think I sense a strange Battle Royale type game…
Assuming these are advanced enough aliens, they'll also be bringing with them all the mass they can, to accentuate the effect? I'm imagining things like Niven's ringworld star propulsion.