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bio website motls.blogspot.com
location Czech Republic
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visits member for 3 years, 3 months
seen 6 hours ago

Hi, I am a string theorist and a publicist.


May
21
comment What are the conditions for decoherence to be irreversible?
Your spin echo and Fermi-Ulam-Pasta examples are really cherry-picked artificially engineered examples where it looks like something should be irreversible but it's not because the processes are really reversible, adiabatic if you wish. The phase space or subspace of the Hilbert space where the systems may get is predictable and tiny, so in this sense it's not right to say that one is producing entropy or entanglement entropy. If you studied proper irreversible generic phenomena, you wouldn't be able to reverse them. The "increase of entropy" in spin echo experiments is an illusion.
May
21
comment What are the conditions for decoherence to be irreversible?
Dear Leon, focusing on the spin echo example, I don't think that they violate the second law in any real way. The properly defined entropy isn't really increasing in the spin echo experiments, so it's not a problem to reverse the phenomenon. So the increase of entropy hasn't really occurred. The analogous thing, decoherence, always has nontrivial loss of the information about the relative phase - that is dispersed in the environment - so it's always irreversible.
May
21
reviewed Approve suggested edit on What energy is transformed to heat when a candle is burned?
May
21
reviewed Approve suggested edit on Nuclear physics problem, Why do we use high weight atomic elements?
May
20
comment Is Shor's algorithm a demonstration of the many worlds interpretation?
Right, that confirms what I say.
May
20
comment Predicting Decay Rates via the Standard Model
You know, people suck compared to what they normally do. ;-)
May
20
comment Is Shor's algorithm a demonstration of the many worlds interpretation?
Well, given your last sentence, you should have said "I am not sure" instead of "This is not true", right? I am confident that prime factorization can't be solved in polynomial time.
May
20
comment Are many-worlds and the multiverse really the same thing?
You will be distangled if you wish, @Anna! ;-) Just throw the article away when you're too entangled. :-)
May
20
answered Why is the sum over string worldsheets of varying genuses unitary?
May
20
answered D-branes wrapping divisors and/or cycles
May
20
answered Are many-worlds and the multiverse really the same thing?
May
20
answered Mathematically rather than physically speaking, is there something “special” about 10 (or 11) dimensions?
May
20
answered Size of the universe
May
19
answered Is acoustic pressure a statistical term?
May
19
answered interpretation of $\{H,L^2\}$
May
19
revised Does this equation mean anything?
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May
19
comment Does this equation mean anything?
It was a pleasure.
May
19
answered Does this equation mean anything?
May
19
revised Does this equation mean anything?
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May
19
revised Is Shor's algorithm a demonstration of the many worlds interpretation?
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