The reversibility tag has no wiki summary.
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How can dynamics be reversible if inflation-style baby universe spawning is allowed?
I just finished readying Sean Carroll's book, "From Eternity to Here", and have a question about reversibility and inflation:
Assume inflation allows random quantum fluctuations to produce high ...
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1answer
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Reversible gates
Is it possible to make any gate reversible merely by retaining the input bits in the
output and introducing ancilla bits as necessary? That is, given an irreversible
gate with $k$ inputs and $l$ ...
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2answers
89 views
What is evidence for an irreversible change?
Knowing some about thermodynamics and reactions, I do understand how it can be shown that a change is reversible. But irreversible? Why can't it be that a change that was deemed irreversible thousands ...
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2answers
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What is the nature of the correspondence between unitary operators and reversible change?
Why does the formalism of QM represent reversible changes (eg the time evolution operator, quantum gates, etc) with unitary operators?
To put it another way, can it be shown that unitary ...
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3answers
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Thermodynamically reversed black holes, firewalls, Casimir effect, null energy condition violations
Scott Aaronson asked a very deep question at Hawking radiation and reversibility about what happens if black hole evolution is reversed thermodynamically. Most of the commenters missed his point ...
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2answers
924 views
Why do reversible processes not increase the entropy of the universe infinitesimally?
The book Commonly Asked Questions in Thermodynamics states:
When we refer to the passage of the system through a sequence of internal equilibrium states without the establishment of equilibrium ...
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3answers
327 views
Hawking radiation and reversibility
It's often said that, as long as the information that fell into a black hole comes out eventually in the Hawking radiation (by whatever means), pure states remain pure rather than evolving into mixed ...
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2answers
56 views
Heuristics for definitions of open and closed quantum dynamics
I've been reading some of the literature on "open quantum systems" and it looks like the following physical interpretations are made:
Reversible dynamics of a closed quantum system are represented ...
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2answers
124 views
Is there any scientific evidence that demonstrates why time passes?
Is there any scientific evidence that demonstrates why time passes?
Or is it just an opened question?
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4answers
799 views
How slow is a reversible adiabatic expansion of an ideal gas?
A truly reversible thermodynamic process needs to be infinitesimally displaced from equilibrium at all times and therefore takes infinite time to complete. However, if I execute the process slowly, I ...
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4answers
332 views
Irreversible expansion and time reversal symmetry
Suppose there are N non-interacting classical particles in a box, so their state can be described by the $\{\mathbf{x}_i(t), \mathbf{p}_i(t) \}$. If the particles are initially at the left of the box, ...
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3answers
336 views
Intuitively, why is a reversible process one in which the system is always at equilibrium?
A process is reversible if and only if it's always at equilibrium during the process. Why?
I have heard several specific example of this, such as adding weight gradually to a piston to compress the ...
