
#19
Mar2212, 12:09 PM

Sci Advisor
P: 4,496

See also http://xxx.lanl.gov/abs/1009.4072 



#20
Mar2212, 01:05 PM

P: 344

Demystifier, I don't follow. He says clearly "in the absence of collapse", then you keep saying "no, because, collapse....".
Also, why is quantum Zeno a disproof of Copenhagen? 



#21
Mar2212, 02:10 PM

P: 1,583





#22
Mar2312, 04:21 AM

Sci Advisor
P: 4,496

Quantum Zeno (or more generally, decoherence) demonstrates that there is no strict border between classical and quantum. More precisely, the density matrix evolves continuously during a finite (but typically very short) time from quantum to classical. In this sense, measurement can at least partially be described by quantum mechanics. In particular, by certain physical definition of measurement apparatus, something closely related to "partial collapse" (that is, partial diagonalization of the density matrix) is possible. 



#23
Mar2312, 04:25 AM

Sci Advisor
P: 4,496





#24
Mar2312, 06:12 PM

P: 1,583





#25
Mar2512, 08:13 AM

Sci Advisor
P: 4,496





#26
Mar2512, 05:53 PM

P: 1,583





#27
Mar2712, 11:06 AM

Sci Advisor
P: 4,496

(i) the multiworld, and (ii) the single world we actually see By knowing Hamiltonian, initial quantum state, and the Schrodinger equation, you can predict everything about the multiworld. In particular, you can predict that this multiworld will consist of MANY ordinary worlds. But it does not tell how to single out one particular single ordinary world out of this big set containing many ordinary worlds. 



#28
Mar2812, 10:25 PM

P: 1,583





#29
Mar2912, 02:00 AM

Sci Advisor
P: 4,496

See also this very readable, good, short recent paper on it: http://lanl.arxiv.org/abs/1110.0549 [to appear as a Brief Review in Modern Physics Letters] 


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