1
vote
0answers
25 views

Quantum entaglement and the arrow of time

This recent article claims there is research that quantum entanglement explains the arrow of time i.e. macroscopic irreversibility. However, as I understand, irreversibility has been been ...
0
votes
2answers
77 views

On the distinction of past and future: could one theoretically reverse direction of particles and cause time to appear to go backwards?

Based on my understanding of physics after seeing The Distinction of Past and Future on Project Tuva, there is no distinction between past and future on a fundamental level- all particle interactions ...
8
votes
1answer
189 views

Will entropy continue to increase even if the universe begins to contract?

If the universe is heading for a big crunch, when the universe starts to collapse will entropy decrease and the arrow of time consequently reverse or not? I'm interested in the explanations, not just ...
4
votes
4answers
411 views

Entropy as an arrow of time

From what I understand, entropy is a concept defined by the experimentalist due to his ignorance of the exact microstate of a system. To say the number of accessible microstates $W$ of the universe is ...
4
votes
2answers
146 views

Does it make a sense to speak about age of electron or atom?

It's possible that this question is too soft or even quite senseless for this forum, but I will ask nevertheless. Everyday (macroscopic) things, like a grandfather's pendulum clock or the grandfather ...
4
votes
1answer
158 views

What happens at the interface between two universes with opposite thermodynamic arrows of time? [closed]

I was trying to think but cannot figure it out. For instance, if the interaction is small, for instance limited to a windows, the observers in each universe will see that the other goes in reverse. ...
8
votes
2answers
367 views

Spontaneous conversion of heat into work at negative temperatures

Consider a heavy macroscopic object moving in a gas. Friction causes its kinetic energy to be converted into heat. Thermodynamically, there is (effectively) no entropy associated with the kinetic ...
4
votes
3answers
417 views

Is there a mechanism for time symmetry breaking?

Excluding Thermodynamic's arrow of time, all mathematical descriptions of time are symmetric. We know the arrow of time is real and we know the equations describing physics are real so is there any ...
4
votes
2answers
852 views

Why does the law of increasing entropy, a law arising from statistics of many particles, underpin modern physics?

As far as I interpret it, the law of ever increasing entropy states that "a system will always move towards the most disordered state, never in the other direction". Now, I understand why it would ...
6
votes
4answers
636 views

Second Law of Thermodynamics and the Arrow of Time: Why isn't time considered fundamental?

I've come across this explanation that the "arrow of time" is a consequence of the second law of thermodynamics, which says that the entropy of an isolated system is always increasing. The argument is ...
-2
votes
1answer
255 views

Loschmidt's paradox - really a paradox? [duplicate]

Is Loschmidt's paradox a paradox even today? In other words, is the paradox resolved or not?
6
votes
1answer
481 views

Wick rotation and the arrow of time

It is well known that we can switch from a statistical system to a quantum mechanical system by a Wick rotation. Has this rotation some implication on the way the time flow? namely, this is an ...
7
votes
6answers
989 views

Does the scientific community consider the Loschmidt paradox resolved? If so what is the resolution?

Does the scientific community consider the Loschmidt paradox resolved? If so what is the resolution? I have never seen dissipation explained, although what I have seen a lot is descriptions of ...
2
votes
1answer
177 views

Do all closed systems, only considering kinematic/mechanical principles, exhibit time reversal symmetry?

It makes a lot of sense to me to imagine a cannonball flying through space as not so much experiencing a macroscopic non-conservative drag force, but as pushing a bunch of air molecules and giving ...
0
votes
3answers
326 views

Has anyone theorized a connection between entropy and quantum uncertainty?

I apologize if this kind of idle theorizing is frowned upon here, but I was wondering if it is possible that the Second Law of Thermodynamics is a consequence of quantum uncertainty. I've heard ...
9
votes
3answers
2k views

Why does the low entropy at the big bang require an explanation? (cosmological arrow of time)

I have read Sean Carrol's book. I have listened to Roger Penrose talk on "Before the Big Bang". Both are offering to explain the mystery of low entropy, highly ordered state, at the Big Bang. Since ...