Questions tagged [poincare-recurrence]
The poincare-recurrence tag has no usage guidance.
43
questions
-2
votes
0
answers
30
views
Can Poincaré recurrences happen eventually in a universe with zero vacuum energy?
I am interested in the topic of possible vacuum up-tunneling and down-tunneling events in cosmology. One popular instance of this is a vacuum decay from a metastable vacuum energy level to a "...
- 2,472
2
votes
0
answers
71
views
On vacuum energy in a de Sitter universe?
I have a couple of questions about de Sitter cosmological horizons. Initially I made a single post containing the two questions, but after some suggestions, I asked them in two separate posts. This ...
- 2,472
0
votes
2
answers
98
views
Is the time evolution of the universe cyclic? [closed]
If we can assume that quantum mechanics does not have a bound on its applicability, i.e. there are no inherently classical properties of the universe, we can represent the physical state of the entire ...
-1
votes
2
answers
147
views
If you shake this sphere with sand for $n$ times ($n$ could be as large as you want), will the sand come back to its original arrangement?
"According to the Poincaré theorem, the sand will eventually come back to its original arrangement after a large number of shakes. But based on intuitive thinking, if you shake it well, the sand ...
- 208
0
votes
0
answers
32
views
Poincaré recurrence in a closed universe? [duplicate]
Is it possible that the Poincaré recurrence applies to a closed universe (with a finite spacetime)? If it is, would this mean that a closed universe could eventually reach the same state as its ...
- 2,472
0
votes
1
answer
106
views
Entropy reversal in an infinite static universe?
As far as I know, entropy could be reversed by the Poincaré recurrence theorem if it had a finite horizon given by some amount of vacuum energy causing an accelerating expansion.
However, I found this ...
- 2,472
0
votes
0
answers
109
views
Could entropy ever be reversed in the universe with infinite time?
In the far future there will be most likely a point where a maximal state of entropy will be reached in the universe where no more useful work could be done and no structures would form, reaching a ...
- 2,472
0
votes
0
answers
78
views
In the many-worlds interpetation, does quantum revival imply that the universe will repeat itself?
Quantum revival is the idea that unitary evolution of the wavefunction implies that evolution of the wavefunction is periodic. Since the many-worlds interpretation stipulates that there is only ...
- 2,193
3
votes
1
answer
278
views
Poincaré Recurrence Theorem in Quantum Mechanics
The recurrence theorem of Poincaré tells us that EVERY open set in the phase space will be crossed infinitely often. It doesnt matter if the open set is a neighbourhood of the initial data set or not.
...
- 159
1
vote
0
answers
147
views
Is it possible for the universe to return to the exact current state if information cannot be lost?
My understanding is that, if information in the universe cannot be lost, it will always be possible (in principle) to tell which prior state of the universe has led to the current state. Is this true ...
1
vote
0
answers
180
views
Poincaré Recurrence Theorem and the 2º Law of Thermodynamics [duplicate]
I am currently working on a 15 pages project about ergodicity and I wanted to include some discussion about the Poincaré Recurrence Theorem (PRT) and, as far as I know, it contradicts the 2° Law of ...
- 154
3
votes
1
answer
133
views
How can we generalize the Poincaré recurrence time to other sets of events?
I know that the Poincaré recurrence tells us that every given physical arrangement in a finite physical space will eventually recur given enough time.
However, as I was thinking about it, even if my ...
5
votes
3
answers
15k
views
Are the claims about repeating states and space in Netflix's "A Trip to Infinity"'s based on real research?
I just watched Netflix's documentary on infinity "A trip to infinity". They have an example where you put an apple in a perfectly sealed box. They make a claim that seems odd to me.
The ...
- 61
4
votes
1
answer
229
views
Liouville's Theorem & Flows in Phase Space for Particle in a Box
A Hamiltonian system of $100$ interacting oxygen atoms, each of mass $16$
$m_p$, is confined within a cubical box of sides $1 m$. The average initial
speed of each particle is $300 ms^{-1}$. Estimate ...
- 545
2
votes
1
answer
414
views
What is the Poincare recurrence of the OBSERVABLE universe?
I have heard about a number called the Poincare recurrence time on Numberphile. It did not seem that exact in the way that it calculated this number, which was a power tower of 10s.
What is the ...
- 465