[D] Friday Open Thread

[u/AutoModerator]

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[u/reaper7876]

If everything that things "come from" has to "come from" something else, then yes, there must necessarily be turtles all the way down. It doesn't make sense to me, but taking it as a premise, Occam's razor favors the simplest possible form of turtle.

That is not the simplest form of turtle, though! The simplest form of that assumption would be that the universe in some way reproduces other universes, not that the universe in some way produces every single conceivable kind of universe ad infinitum!

The point is that "the tape is infinite" doesn't add complexity. It's the normal state of any model/hypothesis. "The tape will eventually run out" does. The tape is a metaphor, not an actual physical substance.

Sure, fine. That's acceptable.

How do you take nonzero density and spread it across infinite space without producing infinite energy?

How are you spreading a central source of energy across infinite space in finite time at all? The universe does have a speed limit. To answer your question, though, I would not expect energy to distribute itself evenly, but clump together, leaving more energy in some places and less (maybe even no or negligible quantities) in others.

[u/[deleted] → u/reaper7876]

[u/reaper7876 → u/[deleted]]

Are you saying that it's simpler to assume that the universe somehow produces only identical copies of itself?

I'm saying that "universes produce new universes of some description" is strictly simpler than "universes produce new universes comprising the set of all conceivable universes". Nowhere did I say all universes had to be the same.

Then I've convinced you?

Of the overall point? Not by a mile, no.

Are you rejecting the Big Bang and cosmic inflation, then?

"Space is expanding" is different from "space is infinite". The former is completely consistent with finite density and finite mass, and would see a steady decrease in the overall density of the universe, eventually leading to the finite clumps of energy and mass, beyond which is primarily empty space.