Re: neutrino mass

[harvey.picker@mail.cc.trincoll.edu (Harvey Picker)]

> Message text written by INTERNET:phys-l@atlantis.uwf.edu
> > It bothers me greatly to see this news media event. These guys aren't
> > announcing their result on the publication date; they're announcing
> > that they've submitted it to PRL!<
>
> Leigh, they are giving a talk at a conference, thus "publishing" their
> data.
>
> I've seen claims that this discovery (if correct) "cooks" the Standard
> Model, or at least will force its modification, but my impression is that
> the Standard Model says nothing about neutrino masses and that
> they are set arbitrarily to zero just because that is the simplest
> assumption.
> But that any other (small) value would also be fine, so this result, albeit
>
> very interesting, will not produce an improvement of the Standard Model.
> Correct?
>
> Bill Larson
> Geneva

Dear Bill,

Since the Standard Model is unable to predict any particle masses, I, too,
can't see  how nonzero neutrino masses can "cook" the Standard Model, as
even the usually reliable Robert Park has announced in _What's New_.
Neutrino masses were set to zero as a convenient assumption in the
"standard" Standard Model.  Now there are perhaps three new free parameters
in the model (or as many as six, if we allow for possible mass differences
between neutrinos and antineutrinos).  It seems to me that this is it.

Solving the missing mass problem would be nice, but if recent reports that
the Hubble expansion is accelerating turn out to be true, that can of worms
appears to be much messier than anyone supposed, even with massive
neutrinos.

While I'm at it, let me correct my senile ramblings in a previous posting.
What I called first the ORCA, then the URCA process is in fact known as
(not surprisingly) the pair process, and it may indeed provide substantial
energy loss in sufficiently hot stars.  The Urca process is an electron
capture on a nucleus followed by a beta decay, with the end result being
the original target nucleus plus a neutrino-antineutrino pair.  This is
energetically impossible in terrestrial surroundings, but the energy needed
can be supplied by a hot photon bath.  The casino was in Rio de Janeiro,
and gamblers' money disappeared bit by bit, not rapidly.  The basic idea is
due to Gamow (like so much else in astrophysics and nuclear physics) and
Schonberg; it was investigated in detail by Tsuruta.  So I had pretty much
completely garbled my account of it.  My only excuse is that my good books
on this stuff were at home.  Sorry for the spreading of misinformation.

I'd have to agree with Leigh Palmer that this is something of a media
circus.  The e-mail announcement from the experimental teams that Jack
Uretsky was kind enough to post to phys-l described the discovery as
unquestionably the most important in neutrino physics since the discovery
of "the" neutrino itself (possibly), and maybe the most important discovery
in particle physics in the last decade.  It seems to me that those sorts of
assessments are for the community of physicists to determine, not the
experimenters.  Then again, it would have been interesting to read the
announcements of the discovery of the J/Psi in 1974 had the Internet
existed back then.

However, cold fusion this ain't.  Anyone who ever tried to compute fusion
rates of light nuclei had to know from the first announcement that cold
fusion was bogus.  The disparity between nuclear length scales and atomic,
molecular, and solid-state length scales guarantees that deuterons can't
get close enough to fuse at room temperature.  Why I even won a $1 bet that
way.

Harvey Picker


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