The theoretical symmetry of physical laws under the transformation of time reversal, that is t -> -t.
Questions tagged [time-reversal-symmetry]
440 questions
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Why does time-reversal mean negation of time i.e. $t\mapsto -t\;?$
Disclaimer : This is a follow-up to this question.
For long time, I've been pondering of this but couldn't come to a stern conclusion to the question:
Why is time-reversal the negation of time $t\;?$ Meant to say, how does negation of time mean the…
user36790
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time reversal symmetry is broken by magnetic field
In literature, the saying "the time reversal symmetry is broken by the external magnetic field" appears very often. How to understand this statement?
user45857
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Is there an intuitive way to see which parameter is invariant under time reverseal?
We know that there are parameters that are even under time-reversal T such as x, E, electric dipole moment, while others are odd, such as momentum p, t and B. Is there an intuitive way to figure out which one is even and which one is odd?
Thi Hoàng
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Why is the position vector invariant under time reversal?
I'm pretty sure I'm misinterpreting something, but my reasoning for why it is not is that when you reverse time, the trajectory in which $x$ follows, namely $x(t)$, changes direction, so that at any given nonzero time {$t_0 | t_0 \ne 0$},
$$x(t_0)…
user279043
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Checking Time Reversal Symmetry
I'm following the Topological Condensed Matter online course by TU Delft. For systems with spin 1/2, time-reversal symmetry as
$$ \mathcal T = i\sigma_y\mathcal K, $$
where $\sigma_y$ is the second Pauli matrix. A Hamiltonian with this kind of…
Manuel E
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Time reversal $t\rightarrow -t$: $0,10,20,30,40,50$ to $-50,-40,-30,-20,-10,0$ or $0,-10,-20,-30,-40,-50\;?$
Time reversal symmetry is defined as $$T:t\mapsto-t\;.$$
Suppose, a stroboscopic film of a ll falling from a certain height to the ground is run forward with time-instances given as: $0,10,20,30,40,50\;.$
When the film is run backward, the ball…
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