Re: Idea to see what Electron sees at near c

Zigoteau wrote:
> Hi, Paul,
>
>
> You have used the wrong words in your question, so that there is no way
> of answering it as stated.
>
> What you want to know is the *cross-section* of the electron for
> *scattering* the photon.
>
> The scattering cross-section is of order of magnitude pi*(2.8fm)^2 ~
> 25e-30 m^2. . 2.8fm is the classical radius of the electron.
>
> It's not a lot. If you look side-on at the neck of a functioning
> cathode ray tube, you can't see the electron beam, although there are
> something like a billion electrons per meter of beam.
>
> > Doesn't the ping-pong still affect the basketball?
>
>
> Yes, absolutely.
>
>
> > What would be the
> > end result of the photon hitting the high-speed electron?
>
>
> The main effect is scattering of the photon. The momentum of the
> electron will also be changed, by an amount depending on which
> direction the photon ends up going.
>
>
> > Would it be
> > the original 400 nm wavelength photon, different wavelength, or zero
> > probability of any interaction?
>
>
> Different wavelength. If the photon is scattered in the direction of
> motion of the electron, it will be blue-shifted; if it is scattered in
> the reverse direction, it will be red-shifted.
>
> Cheers,
>
> Zigoteau.


Thanks for all answers. Mati and Zigoteau you were extremely helpful.

Obviously I am not a trained physicist-- rather a computer programmer.
I have always wanted to see the world from the point of view of
traveling near the speed of light. I have two inexact ideas.

Idea 1
The sensing device would be inside a thick lead box with a pinhole. As
light went through the pinhole, it would eventually cross the path of a
beam of electrons. The beam of electrons would be generated by a
cathode ray tube that can shoot high currents of electrons. Of course,
the beam of electrons would be almost parallel to the path of light
coming through the pinhole. The beam of electrons would be traveling
in the direction away from the photons. So we would have light
traveling toward high-speed electrons. Even though the electrons are
traveling away from the photons, the photons would eventually catch up.
A sensitive photon detector near the electron beam would be fed to a
computer. With enough averages, the computer should pick up the
scattered light off the electron beam. Of course, this would only show
one pixel. To form a complete picture the entire lead box would have
to be rotated to the next area to capture another pixel. The end
result should be a picture of what the electron sees while traveling
near the speed of light sees.

Idea 2
This idea is less attractive. Idea 1 would show what the high-speed
electron sees. Idea 2 would show what electrons traveling at a wide
range of speed would see. Melt tungsten to say 5200 C. There should a
small percentage of electrons traveling near c. Hopefully such
electrons can scatter light to a much higher wavelength. Again we have
the lead box and sensing device inside. Inside the lead box is a pool
of melted tungsten where light enters through the pinhole and shines on
the melted tungsten. Also there would be a sensitive photon detector
viewing the tungsten, which would be feed to a computer. Nearly all
received light will be from the glowing tungsten. Although a small
amount of received light will be photons that went through the pinhole
and then scattered off high-speed electrons; e.g., x-rays and perhaps
gamma rays. I know how to write software that will basically take
thousands of averages to obtain high precision values and then will
subtract the bright glowing light taken from a calibration snapshot.
The calibrated snapshot will be taken inside a solid lead box that did
not have a pinhole. Once the calibrated snapshot is obtained, we can
then put the device back inside the lead box that has the pinhole. The
calibrated snapshot will be used as a means to subtract / remove the
glowing light from further images since we do not want to see the
glowing tungsten light-- just the scattered light that came from the
pinhole. The end result will be a single pixel-- light that went
through the lead pinhole. Again, by rotating the lead box a small
amount left and taking a snapshot, repeating this process to obtain a
full horizontal line of pixels and then rotating the box down a small
degree to the next pixel line and repeating, we would end up with a
full picture. It should see a wide spectrum of light, perhaps from
gamma rays on down to what the photon sensor normally sees.

Thanks for the help!
Paul

.

Relevant Pages

  • Re: Is a fact something that has been proven?
    ... So it's your contention that the electrons go through the slits as ... through the slits (with the detectors turned on) when human knowledge ... A *PAIR* OF ENTANGLED PHOTONS, ...
    (talk.origins)
  • Re: what really are Gravitons?
    ... try not to mix up a photon and a pulse of electromagnetic ... There are no fractional cycles in a standing wave. ... Electrons seem quite real, ... nor units of energy as Einstein asserted. ...
    (sci.physics.relativity)
  • Re: Is a fact something that has been proven?
    ... So it's your contention that the electrons go through the slits as ... experiment and the double slit experiment. ... experiment "without detectors" but then later cheat and peek into what ... Even a single photon "knew". ...
    (talk.origins)
  • Re: Is a fact something that has been proven?
    ... So it's your contention that the electrons go through the slits as ... but the detectors are still "on"? ... Furthermore in a double slit experiment with single ... the behaviour of the initially undetected photon in the ...
    (talk.origins)
  • Re: what really are Gravitons?
    ... try not to mix up a photon and a pulse of electromagnetic ... certain is that these quanta can jiggle electrons and that said jiggling ... There are no fractional cycles in a standing wave. ... nor units of energy as Einstein asserted. ...
    (sci.physics.relativity)