Text 732, 48 rader
Skriven 2006-03-17 23:10:43 av Herman Trivilino (1:106/2000.7)
    Kommentar till text 726 av MIKE ROSS (1:167/133.0)
Ärende: Ghost Particle
======================
 MR> Thank you for posting the PNU766. I didn't see 765 posted but
 MR> the BBS here has been pretty stable though there seemed to be
 MR> a FIDO slowdown on 1 day this past weekend. Perhaps the 765
 MR> posting got lost then. Would you repost 765 once more,
 MR> please? Might it also be possible to repost PNU 758 which
 MR> also managed to fall into a blackhole this last holiday
 MR> season, BTW I think the request itself was lost. FIDO sheesh!

I'll try.  I haven't been getting a reliable feed, lately.  I think it's close
to the end for Fidonet.


 MR> Did you catch the PBS "The Ghost Particle" documentary on
 MR> NOVA? It seemed this physicist on the show was all excited
 MR> that all the matter in the universe was descended from
 MR> neutrinos. I have an idea that neutrios are more peculiar
 MR> than even suspected.

I was on vacation and missed that one.  I'll have to catch the rerun.

 MR> For example, it is a particle which carries energy, travels
 MR> at or near c, and is so nearly massless it doesn't interact
 MR> with matter. The other particle which seems like a close
 MR> cousin is the photon and it transmits an oscillation of
 MR> magnetic and electric energy.

The neutrino is a cousin of the electron.  There are six leptons, the electron
is the most famous of them.  The three neutrinos are also leptons.

The neutrino is not at all like a photon.  In fact, all of nature's particles
are either fermions or bosons.  Since the neutrino is a fundamental fermion,
and the photon a fundamental boson, they about as fundamentally different as
two particles can be.

Historically, the exciting thing about neutrinos was that their existence was
predicted before they were discovered.  For decades they were thought to be
massless, but in the last 10 years the evidence that they have a tiny nonzero
mass was welcomed by theorists, who had been having trouble accounting for
their lack of numbers in the solar emission.

You see, a massless neutrino would travel at light speed, and so not be able to
experience time.  Thus it would be unable to decay into something else, so the
missing solar neutrinos was a grand mystery.  If they do have mass they could
decay, or do something like that.  Theorists refer to neutrino oscillations,
where neutrinos change flavor.

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 * Origin: Big Bang (1:106/2000.7)