[extropy-chat] Re: Damien grants psi evidence

[scerir]

From: "Hal Finney" 

> Proponents of a delayed choice interpretation 
> suggest that the photon somehow has to decide 
> whether it will be a particle or a wave at the
> time it enters the apparatus, [...]
> But really, that is a pretty absurd notion, 
> that photons decide in this way.

Yes, that is the point.

There are situations ( see J.A. Wheeler here
http://www.irims.org/blog/figures/  )
in which the outcome (i.e. wave or particle)
depends on "where" you measure, or on
"when" you measure.

There are situations (theoretical! no exp. has been
performed) in which the measurement is performed 
in the same "where" and in the same "when", by 
a detector or by a different detector, and the 
outcome is different (wave in the first case, 
particle in the latter case). Meaning, perhaps, 
that the measurement apparatus may have some 
retro-causal effect on the very formation of the 
interference pattern.

There are situations (experiments with entangled 
photons) in which we can not say anything untill
both photons have been registered. See, i.e.,
http://www.arxiv.org/abs/quant-ph/9903047
(the abstract saying that 'experimental results 
demonstrated the possibility of simultaneously 
observing both particle-like and wave-like behavior 
of a quantum via quantum entanglement' is manifestly
wrong). Or, from another p.o.v.,
http://people.bu.edu/alexserg/TwoNotTwo.pdf

For a good collection of experiments (quantum optics,
entangled photons, quantum holography, etc.) see:
http://www.loqnl.ufal.br/publications/list.html
http://people.bu.edu/alexserg/references.html

Birgit Dopfer thesis here is a masterpiece,
but she does not write in english :-)
http://www.quantum.univie.ac.at/publications/thesis/

Outstanding papers are
http://physics.sejong.ac.kr/~particle/paper/RMP0S274.pdf
http://www.physik.fu-berlin.de/~simons/
Publikationen/RevModPhys99.pdf
http://www.ap.univie.ac.at/users/Gregor.Weihs/photonintro.pdf