[extropy-chat] Somedays the universe delivers

scerir scerir at libero.it
Wed Apr 25 07:45:24 UTC 2007


Robert:
> > > *Quantum Physics Parts Ways with Reality*

me:
> >http://arxiv.org/abs/0704.2529

Damien:
> Commenting on this, a guy pointed me to his paper at:
> <http://www.boundary.org/articles/Physics_without_Causality.pdf>Physics
> without Causality-Theory and Evidence, Richard Shoup, 2006
> Abstract: The principle of cause and effect is deeply rooted in human
> experience, so much so that it is routinely and tacitly assumed
> throughout science, even by scientists working in areas where time
> symmetry is theoretically ingrained, as it is in both classical and
> quantum physics. Experiments are said to cause their results, not the
> other way around. In this informal paper, we argue that this
> assumption should be replaced with a more general notion of mutual
> influence [...]

In fact. But as you can see from these quotations from that
paper by Zelinger et al. (on 'Nature', 2007) they are well
aware of the other existing conceptual possibilities. 

"It is a very important trait of this model that there
exist subensembles of definite polarizations (independent
of measurements) and that the predictions for the subensembles
agree with Malus' law. It is clear that other classes
of non-local theories, possibly even fully compliant with
all quantum mechanical predictions, might exist that do
not have this property when reproducing entangled states.
Such theories may, for example, include additional
communication [23] or dimensions [24].
[23] D. Bacon and B. F. Toner, Phys. Rev. Lett. 90, 157904 (2003).
[24] Y. Ne'eman, Found. Phys. 16, 361 (1986)."

"We believe that the experimental exclusion of this 
particular class [of nonlocal-realistic models] indicates
that any non-local extension of quantum theory has to be 
highly counterintuitive. For example, the concept of
ensembles of particles carrying definite polarization 
could fail. Furthermore, one could consider the breakdown of
other assumptions that are implicit in our reasoning leading 
to the inequality. These include Aristotelian logic,
counterfactual definiteness, absence of actions into the past 
or a world that is not completely deterministic [30]. We
believe that our results lend strong support to the view that 
any future extension of quantum theory that is in agreement
with experiments must abandon certain features of realistic 
descriptions.
[30] J. S. Bell, Dialectica 39, 103 (1985)."

As pointed out, i.e. by N.Gisin, there is another 
radical conceptual possibility, this one. Quantum theory 
is not a theory about physics, it is just a 'syntax', 
or an 'operating system' of the real (but still unknown) 
theory. The main consequence of this is that the (usual, 
realistic) space-time does not exists at all for such a 
quantum theory /'operating system'. More or less.

s. 







More information about the extropy-chat mailing list