Hi Saibal,
Yes, trans-Plankian physics is likely to be quite different from our
cis-plankian
one. However I think the main reason 't Hooft claims the no-go
theorems of
quantum physics are "in small print" is because his "reading glasses"
are no
longer current :-), I am afraid. His arguments for the prevalence of
simple
deterministic models at this scaled have varied over the years (as his
little
examples) and some of these are quite clever, I'll agree.
However, as you very well point out, any transplankian theory worth
looking
into has to reproduce a recognizable picture of the cisplankian world
we know
and that means: quantum mechanics (non-locality and all) in some
discernible limit (and General Relativity too in some other limit) and
all
indications is that this cannot be done from deterministic models
alone.
't Hooft has been working around this for the last 10 years or so and
he doesn't have much to show for it. Considering that it took him less
than 2 years to come up with a renormalization prescription for
non-abelian gauge
theories in his youth I suspect "god's dice" are loaded against him
this time.
However he is always fascinating to read and hear. I saw him at Harvard
this winter for the Colemanfest and he had the most fabulous
animations...
Godfrey Kurtz
(New Brunswick, NJ)
-----Original Message-----
From: Saibal Mitra <smitra.domain.name.hidden>
To: kurtleegod.domain.name.hidden; marchal.domain.name.hidden.ac.be
Cc: everything-list.domain.name.hidden
Sent: Sat, 13 Aug 2005 01:34:19 +0200
Subject: Re: subjective reality
Hi Godfrey,
't Hooft's work is motivated by problems one encounters in Planck scale
physics. 't Hooft has argued that the no go theorems precluding
deterministic models come with some ''small print''. Physicists
working on
''conventional ways'' to unite gravity with QM are forced to make such
bold
assumptions that one should now also question this ''small print''.
As you wrote, 't Hooft has only looked at some limited type of models.
It
seems to me that much more is possible. I have never tried to do any
serious
work in this area myself (I'm too busy with other things). I would say
that
anything goes as long as you can explain the macroscopic world. One
could
imagine that a stochastic treatment of some deterministic theory could
yield
the standard model, but now with the status of the quantum fields as
fictitional ghosts. If photons and electrons etc. don't really exists,
then
you can say that this is consistent with ''no local hidden variables''.
Saibal
> Hi Saibal,
>
> You are correct that Gerard 't Hooft is one of the world exponents in
> QFTh.
> But Quantum Field Theory is but one small piece of QM and one in
which
> non-local effects do not play a direct role (as of yet).
Understandably
> 't Hooft's forays into Quantum Mechanics have not, however, been
> very insightful as he himself confesses (you can check his humorous
> slides in the Kavli Institute symposium of last year on the Future of
> Physics).
>
> So far he has supplied mostly some interesting simple CA models from
> which one
> can indeed extract something akin to superpositions but that in no
way
> bypasses
> the basic facts of entanglement and non-local correlations.
>
> He may very well be the very last hold out for a deterministic (an
thus
> classically mechanistic) point-of-view but I would not count him out
> just yet. If any one around has the brain to deal with this its him!
> That much I will grant you...
>
> (Now I have met 't Hooft! 't Hooft was a neighbor of mine and I tell
> you: Bruno is no 't Hooft! ;- )
>
> Best regards
>
> Godfrey Kurtz
> (New Brunswick, NJ)
>
> -----Original Message-----
> From: Saibal Mitra <smitra.domain.name.hidden>
> To: kurtleegod.domain.name.hidden; marchal.domain.name.hidden.ac.be
> Cc: everything-list.domain.name.hidden
> Sent: Fri, 12 Aug 2005 21:11:30 +0200
> Subject: Re: subjective reality
>
> Godfrey Kurtz wrote
>
> > More specifically: I believe QM puts a big kabosh into any
> non-quantum
> > mechanistic view of the physical world. If you
> > don't get that, than maybe you don't get a lot of other things,
> Bruno.
> > Sorry if this sounds contemptuous. It is meant
> > to be.
>
>
> There aren't many people with a better understanding of QFT than 't
> Hooft.
>
>
>
> http://arxiv.org/abs/quant-ph/0409021
>
>
> http://arxiv.org/abs/gr-qc/9903084
>
>
> http://arxiv.org/abs/quant-ph/0212095
>
>
> http://arxiv.org/abs/hep-th/0105105
>
>
> http://arxiv.org/abs/hep-th/0104219
>
>
> http://arxiv.org/abs/hep-th/0104080
>
>
>
>
> Saibal
>
>
>
>
>
________________________________________________________________________
> Check Out the new free AIM(R) Mail -- 2 GB of storage and
> industry-leading spam and email virus protection.
>
________________________________________________________________________
Check Out the new free AIM(R) Mail -- 2 GB of storage and
industry-leading spam and email virus protection.
Received on Sun Aug 14 2005 - 12:12:18 PDT