Re: Many Fermis Interpretation Paradox -- So why aren't they here?

From: Saibal Mitra <smitra.domain.name.hidden>
Date: Sun, 20 Oct 1996 14:16:49 +0200

Bruno wrote:

At 16:25 +0200 11/10/1996, Saibal Mitra wrote:

>>You can still have realism, but it must be the >>case that at least some
of
>>the things we think of as ``real physical objects´´ >>like e.g. electrons
are
>>not real.


>What would that mean? What would be real? >Even in my thesis, electrons
>are supposed to have some degree of reality like >relative stability
>as mind pattern in normal machine dreams (1->person plural histories)
>for example.

Well, his theory is rather complicated, but he starts from a deterministic
theory formulated in terms of primordial variables, that do represent ``real
things´´. Although I don't think that his ideas are necessarily correct, it
does give food for thought.

Quantum field theory is really phenomenological of nature. In condensed
matter physics field theory arises by integrating out the small scale
physics, giving rise to a renormalizable field theory, because the non
renormalizable terms flow to zero. So many different microscopic theories
flow to the same macroscopic theory, giving rise to the phenomena of
universality in statistical mechanics. Departure from this universal
behaviour is caused by non renormalizable operators, the effect of which
could be used to distinguish between theories in one universality class.

Since there hasn't been any experimental result that are in disagreement
with the standard model (except for the observation of neutrino oscillations
but this can be accomodated by simple extensions of the standards model), we
can't say anything about what lies beyond the standard model.

So we should at the very least consider ``real elementary particles´´ in the
same way as quantized exitations or pseudo particles that arise in effective
theories in condensed matter physics.

Now one could say that the ``field´´ in QFT is some coarse grained average
of something ``real´´, as it is in condensed matter physics. But even this
doesn't have to be the case. The field itself can be a fictitious object,
that implements some mathematical trick, like so-called ghost fields that
implement contraints arising from gauge symmetries.

Saibal
Received on Sun Oct 20 2002 - 08:17:58 PDT