Randomness in time reversal case

In summary, the article discusses the validity of fluctuation theorems, which are a generalization of thermodynamics on small scales. The article does not mention reversing time or any other specific concept.
  • #1
elementHTTP
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0
I have dice whit starting temperature of 0 K in vacuum and its displaying number 1 ,after drop it displays number 6 (for example) .
Now if we reverse time, will dice sitting still on surface return to original position (displaying number one ) or it will display different random number ?
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  • #2
Since we cannot reverse time, I don't see that this question has an answer. (We could of course film this and play the film backwards, but I don't think this is your question)
 
  • #3
If time would be reversed in your example, why wouldn't the dice return to the previous position? After all this is effectively a reverse process nothing new would occur in it.
 
  • #4
elementHTTP said:
I have dice whit starting temperature of 0 K in vacuum and its displaying number 1 ,after drop it displays number 6 (for example) .
Now if we reverse time, will dice sitting still on surface return to original position (displaying number one ) or it will display different random number ?

The way you stated your question makes it ambiguous. What does "reverse time" mean specifically in this case? Is it different than what we mean when we talk about time reversal symmetry?
 
  • #5
TheNerdConstant said:
If time would be reversed in your example, why wouldn't the dice return to the previous position? After all this is effectively a reverse process nothing new would occur in it.

The problem with this answer is that, as Vanadium50 says above it and Drakkith says below it, no one has any idea what either you or the original poster mean when you talk about " reversing time". There are at least three plausible interpretations of what the original poster means, and the answer is different for each one of the three (which is a nice trick for what looks like a yes/no question with only two possible answers).

So let's hold off on trying to answer the question until we know what is, OK?
 
  • #6
Violation of second law of thermodynamics .
I was reading this article http://medienportal.univie.ac.at/presse/aktuelle-pressemeldungen/detailansicht/artikel/never-say-never-in-the-nano-world/
 
  • #7
elementHTTP said:
Violation of second law of thermodynamics .
I was reading this article http://medienportal.univie.ac.at/presse/aktuelle-pressemeldungen/detailansicht/artikel/never-say-never-in-the-nano-world/
It's seldom wise to trust summaries of new scientific work that have been written for the general public, and this article is no exception. You would think from reading it that the researchers have found interesting violations of the second law of thermodynamics that challenge our understanding of the forward-only motion of time at the nanoscale. But if you look at the abstract of the actual scientific paper (the paper itself is behind a paywall :headbang:) you will see that they've done something very interesting but not as much fun for the university PR department to write about (emphasis mine):
Fluctuation theorems are a generalization of thermodynamics on small scales and provide the tools to characterize the fluctuations of thermodynamic quantities in non-equilibrium nanoscale systems. They are particularly important for understanding irreversibility and the second law in fundamental chemical and biological processes that are actively driven, thus operating far from thermal equilibrium. Here, we apply the framework of fluctuation theorems to investigate the important case of a system relaxing from a non-equilibrium state towards equilibrium. Using a vacuum-trapped nanoparticle, we demonstrate experimentally the validity of a fluctuation theorem for the relative entropy change occurring during relaxation from a non-equilibrium steady state. The platform established here allows non-equilibrium fluctuation theorems to be studied experimentally for arbitrary steady states and can be extended to investigate quantum fluctuation theorems as well as systems that do not obey detailed balance.
So there's no "reversing time" going on, and no better answer to your question than the one that Vanadium-50 gave you above.
 
  • #8
Closed, and I'm going to take advantage of this opportunity to remind everyone that PF rules require providing sources. Stuff like this is the reason why.
 

FAQ: Randomness in time reversal case

What is time reversal in the context of randomness?

Time reversal refers to the process of reversing the direction of time in a system or event. In the context of randomness, it is the concept of reversing the sequence of events or outcomes in a random process.

Can randomness be reversed in time?

No, randomness cannot be reversed in time. Randomness is a fundamental concept in physics and it is considered to be irreversible. This means that the sequence of events or outcomes in a random process cannot be reversed.

How does time reversal affect the predictability of randomness?

Time reversal has no effect on the predictability of randomness. In a truly random process, the outcomes are unpredictable regardless of the direction of time. Time reversal simply changes the sequence of events, but does not alter the randomness of the process.

Are there any real-life applications of time reversal in randomness?

There are no practical applications of time reversal in randomness. However, the concept of time reversal is used in theoretical physics to understand the behavior of systems in which time is reversible, such as quantum systems.

How is time reversal related to the concept of entropy?

Time reversal is closely related to the concept of entropy, which is a measure of the disorder or randomness in a system. In a time-reversible system, entropy remains constant over time, whereas in a non-time-reversible system, entropy increases over time. This is because time reversal preserves the order of events, while the natural flow of time leads to an increase in entropy.

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