X-Message-Number: 22090
From: "michaelprice" <>
References: <>
Subject: More on infinities in physics
Date: Fri, 27 Jun 2003 20:22:17 +0100

In response to Yvan Bozzonetti writing about infrared
divergences in quantum field theory, I said:
>> No heuristic argument based on the uncertainty principle
>> can stand against the detailed calculations of quantum field
>> theory, since the latter includes the former.

and Yvan responded:
> Once more I disagree:Quantum Field Theories are not the
> end of the road, SuperSymmetries for example are not QFT,

Not true.  Supersymmetry does not dethrone quantum field theory;
Supersymmetry is a theory *within* the broader QFT paradigm.
Don't take my word for it, instead read the June 2003 Scientific American
article "Physics Beyond the Standard Model" which discusses the
relationship between supersymmetry and quantum field theory.

> and here the Heisenberg's principle holds too:

Of course it does.  Do you imagine I said it didn't?  Please reread what
I originally said (still quoted above).  I am not saying that the Heisenberg
Uncertainty Principle is incorrect, only that your heuristic rendition or
application of it is flawed since it contradicts the results of QFT,
the latter which already incorporates the uncertainty principle.

> So it is not a subelement of QFT.

Incorrect.  Supersymmetry is a theory that uses the QFT machinery.

> It is used by them and if you think QFT disproves the uncertainty
> principle,

which I don't.  You have misinterpreted my statements.

> the simplest solution is that you have badly digested them,
> sorry Michael.
>
Or that you have misread what I said.

Robert Ettinger writes::

> 4. I now have Kaku's QUANTUM FIELD THEORY to go
> with my older books on QED.  It would take me several years
> to master all the details, if I could live that long and had nothing
> else to do,

I feel the same way, except that I would substitute 'decades' for
'years'!  It should be easy work for the suitably enhanced mentalities
in the future.  Alas, a luxury that is not available to us here and now.

> but he has some things to say about the state of the theory that
> leave a good deal of room for speculation. For example, he says:
>
> "One of the most remarkable properties of supersymmetry is
>  that supersymmetric field theories can be finite to all orders
>  in perturbation theory, which was once thought to be impossible.
>  In some sense, these theories answer Dirac's old objections to
>  quantum field theory, that renormalization theory was in
>  some sense contrived and artificial."

Yes, but whether those infinities are the same as the infinities that
derive from the infrared divergences is also open to speculation.
The infinity of soft photons derives so naturally from classical
electromagnetism that I suspect they will still be there even after
the more ghastly infinities due to bare charges and whatnot are
dealt with by supersymmetry or whatever.

Cheers,
Michael C Price
----------------------------------------
http://mcp.longevity-report.com
http://www.hedweb.com/manworld.htm

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