photons and reflection
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From: NoEinstein on 8 Dec 2009 14:02 On Nov 27, 7:24 pm, RichD <r_delaney2...(a)yahoo.com> wrote: > Dear RichD: You are most correct that photons don't reflect (even from the shiniest mirror). All photons get absorbed by the surface and the electron orbits re emit light of the correct wave length. Matter in the 'reflecting' surface doesn't need to KNOW the angle of the mirror face. All of the atoms near the surface act to absorb the "off angle" photons being re emitted such that only those photons which have your stated angle can escape the surface. NoEinstein > > According to the wave theory of light, angle of > incidence equals angle of reflection. No problem, > in theory or fact. > > However, per QM, light falls as a 'rain' of photons. > What happens then? As I understand it (big qualifier > there), the photons are absorbed by surface atoms. > Electrons jump to higher energy orbitals, then fall > back to ground state, emitting photon(s) of its > characteristic spectrum. Simple.... > > This raises several questions, regarding geometry... > the aforementioned angles are defined relative > to a surface normal. But the surface is not truly > continuous, it's atomic and chunky. How does an > atom know where the 'normal' is? How does it > know which direction to fire its photons, after a > time delay? Does it have some sort of 'light > momentum' memory? > > I never studied quantum field theory, maybe it's > explained there... > > -- > Rich
From: BURT on 8 Dec 2009 15:54 On Dec 8, 3:39 am, p.kins...(a)ic.ac.uk wrote: > BURT <macromi...(a)yahoo.com> wrote: > > The truth is meant to be known. Quantization is the lesser > > concept than full ranges of energy. > > The process of quantization doesn't require discrete, countable > sets of EM mode functions (although that may well make the > mathematics easier). Quantization doesn't necessarily restrict > the allowed energies. Quantization is defined as making energy transitions discrete for the electron. It does not accomadate a mirror. Show me where I am wrong. Mitch Raemsch > > -- > ---------------------------------+--------------------------------- > 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/
From: George Herold on 8 Dec 2009 15:59 On Dec 8, 11:16 am, "Androcles" <Headmas...(a)Hogwarts.physics_q> wrote: > "George Herold" <ggher...(a)gmail.com> wrote in message > > news:0497f18c-647c-4792-a268-197905b5f01d(a)u7g2000yqm.googlegroups.com... > On Dec 7, 10:53 am, "Androcles" <Headmas...(a)Hogwarts.physics_q> wrote: > > > > > > > "Bob Masta" <N0S...(a)daqarta.com> wrote in message > > >news:4b1d0fb6.1129688(a)news.sysmatrix.net... > > > > On Sun, 6 Dec 2009 20:31:18 -0800 (PST), BURT > > > <macromi...(a)yahoo.com> wrote: > > >>If light is a particle which of its waves is this particle in? its > > >>magnetic wave or electric wave? > > > > Yes. Don't think of this as "either-or", think of > > > the photon as the oscillation between magnetic and > > > electric fields. To use a mechanical analogy, you > > > might think of the photon as a rubber ball flying > > > through space. It is springy in the X and Y > > > dimensions, and oscillates between having its > > > energy stored in X-compression/Y-elongation, > > > versus Y-compression/X-elongation. > > > > Now take away the ball. > > > > Best regards, > > > > Bob Masta > > > Quite right, Bob. I sometimes use a "leapfrog" analogy, the electric > > field creates the magnetic field as the electric collapses and then the > > magnetic creates the electric field in turn. > >http://www.androcles01.pwp.blueyonder.co.uk/AC/AC.htm-Hide quoted text - > > > - Show quoted text - > > Hi Androcles. I use to like this analogy too. Until I learned a few > years ago that in E-M radiation the E and B are in phase! > =========================================== > Then you should unlearn it immediately. If E and B were in phase > both would be zero simultaneously and that violates the first law of > thermodynamics, you'd create energy from nothing. > http://en.wikipedia.org/wiki/First_law_of_thermodynamics > But anyway, Maxwell's equations never did claim E and B were in phase, > what you've "learnt" is a rumour spread by the incompetent. > =========================================== > > At first I > thought there was a mistake... but then discovered that the mistake > was mine. (Your link shows correctly the in phase behavior so I > realize I'm not telling you anything you don't know.) > > Anyway the analogy can lead to false conclusions. (At least for me.) > > So now I see that the E field at some time was 'created' by some B > field at a previous time.... > ============================================ > Any spark will start the process. A flame is a chemical reaction > whereby the electrons of the atoms are rearranged to build a different > molecule. 2H2 + O2 -> 2H2O. > ============================================ > > Which starts to 'weird' me out if think > too hard. All of a sudden I picture 'photons' travelling in both > directions. > > George H. > > =========================================== > Androcles' third law: For every photon there is an equal and > opposite rephoton. > http://www.androcles01.pwp.blueyonder.co.uk/rephoton.gif > (It's Newton's third law applied to E-M waves and allows > for light to travel in beams -- quite simple, really.) > > Of course you'll never see a rephoton without a mirror, it is > travelling away from you. Rephotons are the major cause of > poorly understood spooky entanglement. > > -- > 'By denying scientific principles, one may maintain any paradox.' - Galileo > Galilei > 'There is nothing so easy but that it becomes difficult when you do it with > reluctance.'- Marcus Tullius Cicero > New ideas are old ideas resurrected. - Androcles.- Hide quoted text - > > - Show quoted text - Hmm, Sorry on my second look your picture of a photon has it wrong you've got the E and B fields 90 degrees out of phase. This is exactly what I would have drawn a few years ago. But check out this, http://en.wikipedia.org/wiki/Electromagnetic_radiation There is a picture if you scroll down a bit. George H.
From: BURT on 8 Dec 2009 16:41 On Dec 8, 12:59 pm, George Herold <ggher...(a)gmail.com> wrote: > On Dec 8, 11:16 am, "Androcles" <Headmas...(a)Hogwarts.physics_q> wrote: > > > > > > > "George Herold" <ggher...(a)gmail.com> wrote in message > > >news:0497f18c-647c-4792-a268-197905b5f01d(a)u7g2000yqm.googlegroups.com... > > On Dec 7, 10:53 am, "Androcles" <Headmas...(a)Hogwarts.physics_q> wrote: > > > > "Bob Masta" <N0S...(a)daqarta.com> wrote in message > > > >news:4b1d0fb6.1129688(a)news.sysmatrix.net... > > > > > On Sun, 6 Dec 2009 20:31:18 -0800 (PST), BURT > > > > <macromi...(a)yahoo.com> wrote: > > > >>If light is a particle which of its waves is this particle in? its > > > >>magnetic wave or electric wave? > > > > > Yes. Don't think of this as "either-or", think of > > > > the photon as the oscillation between magnetic and > > > > electric fields. To use a mechanical analogy, you > > > > might think of the photon as a rubber ball flying > > > > through space. It is springy in the X and Y > > > > dimensions, and oscillates between having its > > > > energy stored in X-compression/Y-elongation, > > > > versus Y-compression/X-elongation. > > > > > Now take away the ball. > > > > > Best regards, > > > > > Bob Masta > > > > Quite right, Bob. I sometimes use a "leapfrog" analogy, the electric > > > field creates the magnetic field as the electric collapses and then the > > > magnetic creates the electric field in turn. > > >http://www.androcles01.pwp.blueyonder.co.uk/AC/AC.htm-Hidequoted text - > > > > - Show quoted text - > > > Hi Androcles. I use to like this analogy too. Until I learned a few > > years ago that in E-M radiation the E and B are in phase! > > =========================================== > > Then you should unlearn it immediately. If E and B were in phase > > both would be zero simultaneously and that violates the first law of > > thermodynamics, you'd create energy from nothing. > > http://en.wikipedia.org/wiki/First_law_of_thermodynamics > > But anyway, Maxwell's equations never did claim E and B were in phase, > > what you've "learnt" is a rumour spread by the incompetent. > > =========================================== > > > At first I > > thought there was a mistake... but then discovered that the mistake > > was mine. (Your link shows correctly the in phase behavior so I > > realize I'm not telling you anything you don't know.) > > > Anyway the analogy can lead to false conclusions. (At least for me.) > > > So now I see that the E field at some time was 'created' by some B > > field at a previous time.... > > ============================================ > > Any spark will start the process. A flame is a chemical reaction > > whereby the electrons of the atoms are rearranged to build a different > > molecule. 2H2 + O2 -> 2H2O. > > ============================================ > > > Which starts to 'weird' me out if think > > too hard. All of a sudden I picture 'photons' travelling in both > > directions. > > > George H. > > > =========================================== > > Androcles' third law: For every photon there is an equal and > > opposite rephoton. > > http://www.androcles01.pwp.blueyonder.co.uk/rephoton.gif > > (It's Newton's third law applied to E-M waves and allows > > for light to travel in beams -- quite simple, really.) > > > Of course you'll never see a rephoton without a mirror, it is > > travelling away from you. Rephotons are the major cause of > > poorly understood spooky entanglement. > > > -- > > 'By denying scientific principles, one may maintain any paradox.' - Galileo > > Galilei > > 'There is nothing so easy but that it becomes difficult when you do it with > > reluctance.'- Marcus Tullius Cicero > > New ideas are old ideas resurrected. - Androcles.- Hide quoted text - > > > - Show quoted text - > > Hmm, Sorry on my second look your picture of a photon has it wrong > you've got the E and B fields 90 degrees out of phase. This is > exactly what I would have drawn a few years ago. > > But check out this,http://en.wikipedia.org/wiki/Electromagnetic_radiation > > There is a picture if you scroll down a bit. > > George H.- Hide quoted text - > > - Show quoted text - Quantization doesn't work for rainbow physics. Mitch Raemsch
From: Androcles on 8 Dec 2009 16:44
"George Herold" <ggherold(a)gmail.com> wrote in message news:bc2be262-2a4f-4ba9-ab61-2140c09aa064(a)b15g2000yqd.googlegroups.com... On Dec 8, 11:16 am, "Androcles" <Headmas...(a)Hogwarts.physics_q> wrote: > "George Herold" <ggher...(a)gmail.com> wrote in message > > news:0497f18c-647c-4792-a268-197905b5f01d(a)u7g2000yqm.googlegroups.com... > On Dec 7, 10:53 am, "Androcles" <Headmas...(a)Hogwarts.physics_q> wrote: > > > > > > > "Bob Masta" <N0S...(a)daqarta.com> wrote in message > > >news:4b1d0fb6.1129688(a)news.sysmatrix.net... > > > > On Sun, 6 Dec 2009 20:31:18 -0800 (PST), BURT > > > <macromi...(a)yahoo.com> wrote: > > >>If light is a particle which of its waves is this particle in? its > > >>magnetic wave or electric wave? > > > > Yes. Don't think of this as "either-or", think of > > > the photon as the oscillation between magnetic and > > > electric fields. To use a mechanical analogy, you > > > might think of the photon as a rubber ball flying > > > through space. It is springy in the X and Y > > > dimensions, and oscillates between having its > > > energy stored in X-compression/Y-elongation, > > > versus Y-compression/X-elongation. > > > > Now take away the ball. > > > > Best regards, > > > > Bob Masta > > > Quite right, Bob. I sometimes use a "leapfrog" analogy, the electric > > field creates the magnetic field as the electric collapses and then the > > magnetic creates the electric field in turn. > >http://www.androcles01.pwp.blueyonder.co.uk/AC/AC.htm-Hide quoted text - > > > - Show quoted text - > > Hi Androcles. I use to like this analogy too. Until I learned a few > years ago that in E-M radiation the E and B are in phase! > =========================================== > Then you should unlearn it immediately. If E and B were in phase > both would be zero simultaneously and that violates the first law of > thermodynamics, you'd create energy from nothing. > http://en.wikipedia.org/wiki/First_law_of_thermodynamics > But anyway, Maxwell's equations never did claim E and B were in phase, > what you've "learnt" is a rumour spread by the incompetent. > =========================================== > > At first I > thought there was a mistake... but then discovered that the mistake > was mine. (Your link shows correctly the in phase behavior so I > realize I'm not telling you anything you don't know.) > > Anyway the analogy can lead to false conclusions. (At least for me.) > > So now I see that the E field at some time was 'created' by some B > field at a previous time.... > ============================================ > Any spark will start the process. A flame is a chemical reaction > whereby the electrons of the atoms are rearranged to build a different > molecule. 2H2 + O2 -> 2H2O. > ============================================ > > Which starts to 'weird' me out if think > too hard. All of a sudden I picture 'photons' travelling in both > directions. > > George H. > > =========================================== > Androcles' third law: For every photon there is an equal and > opposite rephoton. > http://www.androcles01.pwp.blueyonder.co.uk/rephoton.gif > (It's Newton's third law applied to E-M waves and allows > for light to travel in beams -- quite simple, really.) > > Of course you'll never see a rephoton without a mirror, it is > travelling away from you. Rephotons are the major cause of > poorly understood spooky entanglement. > > -- > 'By denying scientific principles, one may maintain any paradox.' - > Galileo > Galilei > 'There is nothing so easy but that it becomes difficult when you do it > with > reluctance.'- Marcus Tullius Cicero > New ideas are old ideas resurrected. - Androcles.- Hide quoted text - > > - Show quoted text - Hmm, Sorry on my second look your picture of a photon has it wrong you've got the E and B fields 90 degrees out of phase. ===================================== It's right. Just ask any electrical engineer. ===================================== This is exactly what I would have drawn a few years ago. ===================================== You'd have been right years ago. ===================================== But check out this, http://en.wikipedia.org/wiki/Electromagnetic_radiation There is a picture if you scroll down a bit. George H. ================================================= Wackypedia is written by both incompetent kooks and the wise. Kooks outnumber the wise by at least 100:1, perhaps a 1000:1. Wackypedia has it wrong. See the discussion page, there are a set of tabs labelled "article", "discussion", "edit this page" and "history" at the top. YOU can edit the page, I refuse to have anything to do with it. Faraday wrote E = -dB/dt. He did not write E = B, he did not write dE/dt = -dB/dt and he did experiment. A CHANGING magnetic field produces an electric field. Ask any generator designer. The kook diagram you've indicated shows E = B. Use this instead: http://en.wikipedia.org/wiki/Trigonometric_functions And do not write - Hide quoted text -- Show quoted text -- Hide quoted text -- Show quoted text -- Hide quoted text -- Show quoted text -- Hide quoted text -- Show quoted text -, it irritates me. Delete it before you post to usenet. |