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| Tags: deflected, electric, fields, light |
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#1
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Note: this thread has been started in sci.physics.research under
http://groups.google.co.uk/group/sci...faf882621f739e , but my reply appears to be kept ignored by the moderators (I have submitted it already three times without getting a response of any sort). I am therefore posting my reply here (also the initial post; any further reference is to posts in the original thread): Eugene Stefanovich wrote: I was wondering lately if light can be deflected by static electric field in a manner similar to the light deflection by gravity fields. Suppose that we shine a laser beam close to the surface of a highly charged metal ball (e.g., in the van der Graaf generator). Will the beam change its direction? Did anybody hear about such experiments? It seems that classical electrodynamics predicts that there will be no deflection. The electromagnetic field in the laser beam and the static electric field of the ball do not interact with each other (E&M theory is linear). On the other hand, quantum electrodynamics has interactions between charges and photons (i.e., those responsible for the Compton effect). My best guess is that these interactions will result in the beam deflection when passing near charged object or between capacitor plates. Thanks. Eugene. I do not see any theoretical reason why light should not be deflected by electric (or magnetic) fields. The point is that in the theory of Classical Electrodynamics the speed of light in vacuum is effectively a free parameter which can only be determined through experiments. In this sense it is theoretically possible that the speed of light depends on the electric or magnetic fields present. If you have a field gradient this would then produce a kind of refraction effect i.e. light would be deflected. I personally think such an explanation could actually explain the well known 'gravitational bending' because the sun (or other astrophysical objects) is surrounded by a plasma halo which, due to its radial inhomogeneity, must be associated with an electric plasma polarization field gradient (on the other hand, I am not aware of any gravitional bending observations and experiments where one could rule out the existence of a plasma halo). By the way, I do not agree with Murat's interpretation above: it would be completely inconsistent with Electrodynamics to describe light as a charged particle in the limit of zero charge and mass (anyway, charge/mass is not a number but has a physical dimension). The experiments quoted by Eugene may rule out that light has a charge, but not necessarily that light is not deflected by electric or magnetic fields, because, as I indicated above, what one requires for this 'field refraction' is a field gradient (in the same way as one needs a density gradient for ordinary refraction). Thomas http://www.physicsmyths.org.uk |
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#2
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#3
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Thom?
Right On!!! How does matter slow down light? What is it about matter that resists light? I think it must be the atom's electromagnetic fields. |
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#4
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wrote in message oups.com... I think it must be the atom's electromagnetic fields. Well that's sorted then. As we all know as long as you think something it must be true and proven. When do you go to Stockholm? |
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#5
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Thomas Smid wrote:
Note: this thread has been started in sci.physics.research under http://groups.google.co.uk/group/sci...faf882621f739e , but my reply appears to be kept ignored by the moderators (I have submitted it already three times without getting a response of any sort). I am therefore posting my reply here (also the initial post; any further reference is to posts in the original thread): Eugene Stefanovich wrote: I was wondering lately if light can be deflected by static electric field in a manner similar to the light deflection by gravity fields. Suppose that we shine a laser beam close to the surface of a highly charged metal ball (e.g., in the van der Graaf generator). Will the beam change its direction? Did anybody hear about such experiments? It seems that classical electrodynamics predicts that there will be no deflection. The electromagnetic field in the laser beam and the static electric field of the ball do not interact with each other (E&M theory is linear). On the other hand, quantum electrodynamics has interactions between charges and photons (i.e., those responsible for the Compton effect). My best guess is that these interactions will result in the beam deflection when passing near charged object or between capacitor plates. Thanks. Eugene. I do not see any theoretical reason why light should not be deflected by electric (or magnetic) fields. The point is that in the theory of Classical Electrodynamics the speed of light in vacuum is effectively a free parameter which can only be determined through experiments. In this sense it is theoretically possible that the speed of light depends on the electric or magnetic fields present. If you have a field gradient this would then produce a kind of refraction effect i.e. light would be deflected. I personally think such an explanation could actually explain the well known 'gravitational bending' because the sun (or other astrophysical objects) is surrounded by a plasma halo which, due to its radial inhomogeneity, must be associated with an electric plasma polarization field gradient (on the other hand, I am not aware of any gravitional bending observations and experiments where one could rule out the existence of a plasma halo). By the way, I do not agree with Murat's interpretation above: it would be completely inconsistent with Electrodynamics to describe light as a charged particle in the limit of zero charge and mass (anyway, charge/mass is not a number but has a physical dimension). It is true that charge/mass is not a number but has a physical dimension in the presently used conventional units. However, one can always measure the electric charge in kilograms at the expense of changing the numerical value and dimension of the Coulomb constant k. This then makes charge/mass a dimensionless number just like (gravitational mass/inertial mass). One should also note that if charge/mass ratio for light turns out to be 1 experimentally, it does not mean that the actual physical electric charge of the photon is different from zero... Murat Ozer The experiments quoted by Eugene may rule out that light has a charge, but not necessarily that light is not deflected by electric or magnetic fields, because, as I indicated above, what one requires for this 'field refraction' is a field gradient (in the same way as one needs a density gradient for ordinary refraction). Thomas http://www.physicsmyths.org.uk |
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#6
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T Wake wrote: wrote in message oups.com... I think it must be the atom's electromagnetic fields. Well that's sorted then. As we all know as long as you think something it must be true and proven. When do you go to Stockholm? The next time I get a chance!!! What is it about matter that resists light? Maybe twake has an answer!!! |
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#7
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your question is *excellent*!!
i wonder if it ever was asked!! no wonder it is an unconvenent question for the paradigm my answer seems to be very simple yes!!! my reason for it is that 1 light is itself an Em wave 2 it has mass ATB Y.Porat ------------------------------------ |
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#8
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and my next question is
why in some cases it is passing through matter though mater has electric fields and in other cases it is deflected like a mirror TIA Y.Porat ------------------------- |
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#9
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wrote in message oups.com... T Wake wrote: wrote in message oups.com... I think it must be the atom's electromagnetic fields. Well that's sorted then. As we all know as long as you think something it must be true and proven. When do you go to Stockholm? The next time I get a chance!!! What is it about matter that resists light? Maybe twake has an answer!!! What is it about matter that resists matter? off topic and out of curiosity - do you understand your "heroes" work on the photoelectric effect? |
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#10
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The structure of an electric field is composed of photons. Photons give
us light. Here we see the dog trying to catch its own tail. Or light waves deflect light waves. (I can live with that) can you all ? Bert |
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