photons and reflection
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From: BURT on 1 Dec 2009 17:58 On Dec 1, 11:26 am, "n...(a)bid.nes" <alien8...(a)gmail.com> wrote: > On Nov 30, 6:33 pm, BURT <macromi...(a)yahoo.com> wrote: > > > > > > > On Nov 30, 6:25 pm, Salmon Egg <Salmon...(a)sbcglobal.net> wrote: > > > > In article <pan.2009.11.30.19.59.55.233...(a)example.net>, > > > Rich Grise <richgr...(a)example.net> wrote: > > > > > Look at a piece of aluminum foil. One side is mirror-smooth, such that > > > > you could see your reflection, if you could make it flat enough. The other > > > > side is matte, and doesn't give a mirror-like reflection. Does help at all? > > > > Use X-band sensitive eyes! > > > > Bill > > > > -- > > > An old man would be better off never having been born. > > > There is no way light can be quantized in energy comming out of the > > atom is it produces a full spectrum of energy levels. > > Well, that explains lasers. No, wait, it doesn't. > > > Mitch Raemsch - Still in the aether of time > > Too bad you refuse to enter the real world. > > Mark L. Fergerson- Hide quoted text - > > - Show quoted text - But it doesn't explain a rainbow. Emission can be quantized but not all of the time. Mitch Raemsch
From: Salmon Egg on 1 Dec 2009 18:53 In article <pan.2009.12.01.21.39.32.326514(a)example.net>, Rich Grise <richgrise(a)example.net> wrote: > So, when do you plan to eat the golden bullet? 'Cause otherwise, you're > going to be one one day. I am one already getting even oldfer. Bill -- An old man would be better off never having been born.
From: p.kinsler on 2 Dec 2009 06:43 BURT <macromitch(a)yahoo.com> wrote: > What wave is the particle of light in? the electric opr > magnetic wave? Here's how the theory can be described (simplified, obviously): (a) solve Maxwell's equations for a suitable system, and get a set of normalizable basis functions allowing you to describe any field configuration. (b) these basis functions usually have both electric and magnetic field contributions; they are usually called "mode functions", and tend to oscillate in space and time (although not all will). (c) quantize the field inside each mode; this gives you a countable series of possible mode excitations. (d) to describe some chosen field configuration, you combine a suitable set of modes containing appropriate quantum excitations. You may need to account for non-trivial correlations between the modes, and between the quantum states in the same and different modes. There is no "particle of light". Instead there are countable excitations of the wave-like field modes. These modes usually combine both electric and magnetic contributions. It's not a particle, it's a wave. But you _can_ count the excitations. -- ---------------------------------+--------------------------------- Dr. Paul Kinsler Blackett Laboratory (Photonics) (ph) +44-20-759-47734 (fax) 47714 Imperial College London, Dr.Paul.Kinsler(a)physics.org SW7 2AZ, United Kingdom. http://www.qols.ph.ic.ac.uk/~kinsle/
From: George Herold on 2 Dec 2009 10:47 On Dec 1, 11:30 am, Louis Boyd <b...(a)apt0.sao.arizona.edu> wrote: > George Herold wrote: > > On Nov 29, 5:12 pm, BURT <macromi...(a)yahoo.com> wrote:> > > "> No. There is no particle of light. It is easily demostratable as a > >>question that cannot be answered." > > > What? You haven't heard of a PMT? (Photomultiplier tube) or the > > photoelectric effect? > > Neither wave or QM theory does a thorough job of explaining the observed > effects of electromagnetic energy interacting with matter. Wave theory > is generally more useful when dealing with propagation, refraction, > reflection and diffraction through and around material objects. > QM is generally more useful when electromagnetic energy interacts with > matter and energy is exchanged. They're both incomplete models of what > happens in nature. Use the one which works best to explain a given > phenomena. Or come up with more complete unified model if you can. > Lots of luck. It's not like others haven't tried with varying degrees > of success but the results are generally are too cumbersome to be useful. "> Neither wave or QM theory does a thorough job of explaining the observed > effects of electromagnetic energy interacting with matter. " Louis, do you have any specific examples in mind? I thought the theorists had a good handle on light. (I'm an experimentalist and am certainly not going to come up with any theories of my own..... I've got enough trouble understanding E&M, let alone QM.) When I measure light it always comes as photons. With a Si Photodiode I get one electron generated for each photon absorbed. George H.
From: George Herold on 2 Dec 2009 10:57
On Dec 2, 6:43 am, p.kins...(a)ic.ac.uk wrote: > BURT <macromi...(a)yahoo.com> wrote: > > What wave is the particle of light in? the electric opr > > magnetic wave? > > Here's how the theory can be described (simplified, obviously): > > (a) solve Maxwell's equations for a suitable system, and get a set > of normalizable basis functions allowing you to describe any field > configuration. > > (b) these basis functions usually have both electric and magnetic > field contributions; they are usually called "mode functions", and > tend to oscillate in space and time (although not all will). > > (c) quantize the field inside each mode; this gives you a countable > series of possible mode excitations. > > (d) to describe some chosen field configuration, you combine a > suitable set of modes containing appropriate quantum excitations. > You may need to account for non-trivial correlations between the > modes, and between the quantum states in the same and different > modes. > > There is no "particle of light". Instead there are countable > excitations of the wave-like field modes. These modes usually > combine both electric and magnetic contributions. > > It's not a particle, it's a wave. But you _can_ count the > excitations. > > -- > ---------------------------------+--------------------------------- > Dr. Paul Kinsler > Blackett Laboratory (Photonics) (ph) +44-20-759-47734 (fax) 47714 > Imperial College London, Dr.Paul.Kins...(a)physics.org > SW7 2AZ, United Kingdom. http://www.qols.ph.ic.ac.uk/~kinsle/ Paul, I feel I'm in way over my head, but is there something wrong with calling the excited quantized mode a photon? George H. |