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Why are the 'Fixed Stars' so FIXED?



 
 
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Old May 7th 07, 08:35 AM posted to sci.physics.relativity,sci.astro
George Dishman[_1_]
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Default Why are the 'Fixed Stars' so FIXED?


"Henri Wilson" HW@.... wrote in message
...
On 6 May 2007 10:32:36 -0700, George Dishman
wrote:
"Henri Wilson" HW@.... wrote in message
. ..
On Sat, 5 May 2007 09:05:10 +0100, "George Dishman"
wrote:
"Henri Wilson" HW@.... wrote in message
m...
On Fri, 4 May 2007 14:16:37 +0100, "George Dishman"

http://www.hqrd.hitachi.co.jp/em/doubleslit.cfm

Yes I'm familiar with that kind of result. De Broglie waves are quite
amazing
really. It shows that matter and 'fields' are not very far apart in
nature.

George, there is nothing here that surprises me. Single photons making
up a
monochromatic beam should have the same wavelength as the beam itself.
The beam
is just 'lots of them'.

Finally, you have cottoned on to what I have been
saying. In the experiment they used a current of
10 electrons per second. Obviously the diffraction
pattern is not what you would predict using a frequency
of 10Hz in your "grating equation". Each electron
behaves entirely independently of the others and
the pattern that builds up is controlled by the
intrinsic properties of an electron. If you use
the interference pattern via Huygens to work out a
wavelength, it is the wavelength of an electron that
you get, not the 29979245.8m wavelength that
corresponds to a frequency of 10Hz.

Yes George, that isn't surprising. The thing is diffracting the De
Broglie
waves of the electrons...whatever they might be.

Now try diffracting a 30000 hz radio wave. It WILL use the corresponding
wavelength.


Yep, exactly the same, but in your other post you
claim there should be some energy deposuted from
the electron beam at the angle corresponding to
10Hz even though all the electrons go where the
De Broglie wavelength says they should.


It's all about probability George. You know...you have been teaching me
about
probability for weeks...


What does that comment have to do with what I
said Henry? I think you're losing it a bit.

Incidentally, did you notice at the top it says

"This detector was specially modified for
electrons from the photon detector produced
by Hamamatsu Photonics (PIAS)."

It is just a photomultiplier with the front end
photoelectric element removed.

It detects single electrons, not single photons...


Henry, it_IS_ a PM tube but without the photoelectric
emitter on the front which of course ejects one electron
per photon. How did you think a PM worked?


that's the ultimate aim...not easy to achieve.


No, that is just a description of how they are
constructed. There is a quantum efficiency that
means that sometimes a photon will fail to eject
an electron but the majority do.

Most PMs are used simply to
amplify very weak light signals.


PMs don't amplify light at all, they convert each
photon into detect an electron and then create a
detection event from that. I repeat, how did you
think they worked?

George


 




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