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The Ghost In The Machine wrote:
> >>
> >> Granted, experiments such as Compton's scattering
> >> and Einstein's photoelectric effect indicate that
> >> something is hitting those electrons, and that something
> >> acts as a collection of bundles of energy which is
> >> frequency-dependent.
> >>
> >> That's as close to "seeing" a photon as one might
> >> possibly get.
> >>
> >
> > Seeing? I can see photons in my spinthariscope.
>
> Interesting little device, that. However, according to
> Wiki it contains a phosphor (zinc sulphide); therefore
> one is seeing the phosphorluminescence therefrom. In some
> ways that makes it a variant of black and white monitor.
>
> I'll admit I'm not sure if one can see single photons
> therefrom or not (it uses a lens to collimate the light
> flashes, or "sparks" -- hence the name Crookes gave it).
> There is also the issue of the "noise reduction circuitry"
> in the eye, optic nerve, or brain, which AFAIK filters
> out anything less than about 5 photons, so that we don't
> get overwhelmed by noise in the dark.
>
> Also, the spinthariscope is triggered by alpha particles.
> If one assumes Th-232 is the sample (the most common),
> the alpha particle apparently is ejected with a mean
> (?) energy of a bout 4.083 MeV. That's enough to generate
> about 1,500-2,000 photons per "spark".
>
> (Nice try, though. :-) )
Filtering photon?.... Sigh :-(
<<Now, does not the prize to Einstein imply
that the Academy recognised the particle
nature of light? The Nobel Committee says
that Einstein had found that the energy exchange
between matter and ether occurs by atoms emitting
or absorbing a quantum of energy,hv .
As a consequence of the new concept of light quanta
(in modern terminology photons) Einstein proposed the
law that an electron emitted from a substance by
monochromatic light with the frequency has to have
a maximum energy of E=hv-p, where p is the energy needed to
remove the electron from the substance. Robert Andrews
Millikan carried out a series of measurements over a
period of 10 years, finally confirming the validity of this
law in 1916 with great accuracy. Millikan had, however,
found the idea of light quanta to be unfamiliar and strange.
The Nobel Committee avoids committing itself to the
particle concept. Light-quanta or with modern terminology,
photons, were explicitly mentioned in the reports on
which the prize decision rested only in connection with
emission and absorption processes. The Committee says
that the most important application of Einstein's photoelectric
law and also its most convincing confirmation has come from
the use Bohr made of it in his theory of atoms, which explains
a vast amount of spectroscopic data. >>
http://nobelprize.org/physics/articles/ekspong/index.html
Sue...
farside.ph.utexas.edu/teaching.html">http://farside.ph.utexas.edu/teaching.html
web.mit.edu/8.02t/www/802TEAL3D/visualizations/light/index.htm">http://web.mit.edu/8.02t/www/802TEAL3D/visualizations/light/index.htm
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