Talk:Time reversibility

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Lead Definition
If a stochastic process is time reversible, then it is not possible to determine, given the states at a number of points in time after running the stochastic process, which state came first and which state arrived later.

Doesn't that describe a time-irreversible system?

18.83.6.12 (talk) 20:39, 24 April 2008 (UTC)


 * I was just thinking the same thing and came here to ask the same question, but I think we may be interpreting the definition wrong. It definately needs clearing up though. —Preceding unsigned comment added by 72.0.208.104 (talk) 10:38, 19 December 2009 (UTC)


 * I think the definition is correct: If you can't tell whether or not a video is playing in reverse, then it depicts a reversible process. (For example, a bouncing ball is reversible, a breaking cup is irreversible. The latter case progresses to state that is more disordered, more statistically likely.) Cesiumfrog (talk) 02:39, 28 July 2013 (UTC)

Cyclical loops
What about if we have a triangle: three equally probable states, with unit transition probabilities in a cycle (a->b, b->c and c->d) but zero transition probabilities in the reverse direction (e.g., b->a)?
 * $$ 1=\pi_x\mu_{xy} \neq \pi_y\mu_{yx}=0 $$

Would this be a useful example or subsection to cover in the article? (Like a square rigger in the roaring forties: revisiting its port of origin despite being only able to journey east.) I guess I can concede how watching this could show which way time was oriented, but still, it seems terribly awkward to have to call a cyclical process irreversible.. Cesiumfrog (talk) 02:39, 28 July 2013 (UTC)

Merger proposal
The article Reversible dynamics appears to me to cover the same topic as this page, and this title seems to be the more broadly used one (and this page is in the better condition of the two), so I propose to merge Reversible dynamics into this page. Any comments or objections? -Bryanrutherford0 (talk) 17:00, 13 January 2016 (UTC)
 * Done. -Bryanrutherford0 (talk) 19:12, 20 January 2016 (UTC)

Mathematics section
What is U in the equation? — Preceding unsigned comment added by Mdcdnaeifkd (talk • contribs) 22:47, 2 December 2018 (UTC)

Time reversibility
I have a crazy idea. This is only a theory, what happens if time reverses after midnight like after 12 PM it's 11PM again and then 10 PM and so on....This may be a good science fiction 😀 43.249.217.253 (talk) 08:37, 7 September 2022 (UTC)