I Can a finite universe end in heat death?

[grauitate]

It is still perfectly possible for timelike worldlines to cross the horizon in the ingoing direction, and time does not "stop" there and periodic processes do not cease. Also, in order for there to be an event horizon at all, as you can see from the definition, there has to be a future null infinity, and a closed universe does not have one.

I'll try to answer as carefully as possible, because I assume there is a fundamental misunderstanding:
Any inside observer in an finite and closed universe can observe the wall of the CMB at z ≅ 1,000...1,500, where all periods of processes are observed slower in the same range as well. Only from the observers view shortly behind this CMB (approx. 10...100 kpc) wall the redshift gallops against z →∞ (but not detectable any more) - of course, that space area is the same like everywhere insinde the universe and does not differ from anywhere inside - this wall, as the word "horizon" suggests, is only an appearance of the observer and has nothing to do with BHs phenomena when radiation or matter is coming from outside in.
Of course, this wall or horizon does not exist in reality in the apparent local area.
The finite and closed universe has no outside, there is only inside. Its dynamic is not the expansion, but it is the splendid and naturally balancing flow processes of structure creation and dissolution taking place visibly and everlasting in the range of our eyes and telescopes from radio to gamma ray frequencies.

Regarding mainstream science, this is not a science covered with concrete. My understanding is that the "salt in the soup" of science should be discussion of proposals at the edge of mainstream or outside to create theories which can avoid the severe problems still existing e.g. in the standard model.

Although invited, I admit that this forum may be is not the appropriate for me. Nevertheless, thank you for your responses.

 

[phinds]

Regarding mainstream science, this is not a science covered with concrete. My understanding is that the "salt in the soup" of science should be discussion of proposals at the edge of mainstream or outside to create theories which can avoid the severe problems still existing e.g. in the standard model..

Yes, that's true, it's just NOT the purview of this forum. Here the focus is ONLY on mainstream science, not beyond the boundaries of it.

 

[PeterDonis]

I assume there is a fundamental misunderstanding

I agree, but I think you're mistaken about whose misunderstanding it is. See below.

Any inside observer in an finite and closed universe can observe the wall of the CMB at z ≅ 1,000...1,500, where all periods of processes are observed slower in the same range as well.

Yes.

Only from the observers view shortly behind this CMB (approx. 10...100 kpc) wall the redshift gallops against z →∞ (but not detectable any more)

No. There are at least two errors here:

(1) The 10...100 kpc you are quoting is not an actual distance; it's a notional number that doesn't correspond to anything anyone actually measures. It certainly does not correspond to a "distance behind the CMB" that some event horizon is at (since there is no event horizon in a closed universe).

(2) In an idealized closed universe model, $z \rightarrow \infty$ corresponds to the initial singularity. In other words, as seen by any observer, any event in the universe (i.e., after the initial singularity) has a finite $z$. This is just another way of saying that there is no event horizon in a closed universe.

this wall

There is no "wall" in a closed universe. See above. You are fundamentally mistaken about what a closed universe model says.

The finite and closed universe has no outside, there is only inside.

This is true of any FRW spacetime, not just a closed one.

My understanding is that the "salt in the soup" of science should be discussion of proposals at the edge of mainstream or outside to create theories which can avoid the severe problems still existing e.g. in the standard model.

PF has a "Beyond the Standard Model" forum where hypotheses about how to extend existing physics can be discussed. But even there you have to have some basis for discussion: some concrete proposal (usually published in a peer-reviewed paper) that makes testable predictions.

However, that is irrelevant to this discussion in any case, because the closed universe model is not an extension of existing physics; it's built using standard General Relativity and the Standard Model and requires no assumptions beyond what is currently known. But in order to discuss it, you have to understand what it actually says, and you don't appear to, as I've explained above.