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</o:shapelayout></xml><![endif]--></head><body bgcolor=white lang=EN-GB link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Grahame:<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Photon momentum is <i>how much space waves</i>. A photon is a wave in space. And space waves more when the wavelength is shorter, because it waves faster. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>All there is, is waves in space. We use pair production to convert them into matter, which is in essence just standing waves in space. So you can’t define these waves in space in terms of matter. You can say they’re transverse waves and you can talk of circular polarization, but you can’t define them in terms of the things that are made of them. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><img width=467 height=187 id="Picture_x0020_1" src="cid:image001.gif@01D27B2F.F885E6D0"></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Regards<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>John D<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'> General [mailto:general-bounces+johnduffield=btconnect.com@lists.natureoflightandparticles.org] <b>On Behalf Of </b>Dr Grahame Blackwell<br><b>Sent:</b> 30 January 2017 12:15<br><b>To:</b> Nature of Light and Particles - General Discussion <general@lists.natureoflightandparticles.org><br><b>Subject:</b> Re: [General] On photon momentum<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>Dear Chandra, Chip, John D, everyone,</span><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US> <o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>I really appreciate all your responses, truly I do.</span><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>BUT - <strong><span style='font-family:"Arial",sans-serif'>NOBODY appears to have answered, or even addressed, my question.</span></strong></span><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><strong><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>(With the exception of Chandra, Vladimir and John D, who actually question the fundamental premise - as I do.)</span></strong><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US> <o:p></o:p></span></p></div><div><p class=MsoNormal><strong><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>My question was a request for a 'text-book' style DEFINITION OF MOMENTUM APPLICABLE TO PHOTONS (not just how it's contained, how it propagates, whatever).</span></strong><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US> <o:p></o:p></span></p></div><div><p class=MsoNormal><strong><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>Without having a clear definition of what momentum IS (in a form applicable to photons), IMO it's utterly meaningless to try and explain/discuss/dispute how it propagates or anything else about it. I don't see such a definition in ANY of the flood of emails following my question.</span></strong><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US> <o:p></o:p></span></p></div><div><p class=MsoNormal><strong><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>If the answer is that no such text-book definition exists, then we have to question whether momentum itself exists as an intrinsic property of momentum.</span></strong><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'> In this I'm at one with Chandra that momentum is rather a characteristic that emerges in reactions involving photons or massive particles - nothing more or less. I'm also with John D that momentum is well characterised by the motion of a wave, and that energy & momentum aren't two different things - momentum is an emergent <strong><span style='font-family:"Arial",sans-serif'>consequence</span></strong> of energy.</span><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US> <o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>[So, Chandra, contrary to your first response, I actually DO like your opinion! It's the only one that makes sense to me.]</span><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US> <o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>I'd further agree 100% with Chandra and Vladimir that 'energy flow' through the ether is rather simply a self-propagating excitation of that ether (Chandra's CTF, Vladimir's node array) - like plucking a (3-dimensional) guitar string and seeing the vibration travel along the string: the vibration, the photon, the material particle, is NOT a physical 'thing' in its own right, it's simply a state-of-being of the ether, one that is self-sustaining (as a point of detail, in my early book I liken a material particle to a whirlpool in a stream - it's not the water, it's the self-sustaining pattern IN the water).</span><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US> <o:p></o:p></span></p></div><div><p class=MsoNormal><strong><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>So unless we have a clear definition of momentum applicable to photons, I see absolutely no point in trying to explain how it happens - how can you discuss how something happens when you can't even define what it is?!</span></strong><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US> <o:p></o:p></span></p></div><div><p class=MsoNormal><strong><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>Again: any offers?</span></strong><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US> <o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>Best regards to all,</span><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>Grahame</span><span lang=EN-US><o:p></o:p></span></p></div><blockquote style='border:none;border-left:solid navy 1.5pt;padding:0cm 0cm 0cm 4.0pt;margin-left:3.75pt;margin-top:5.0pt;margin-right:0cm;margin-bottom:5.0pt'><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif'>----- Original Message ----- <o:p></o:p></span></p></div><div><p class=MsoNormal style='background:#E4E4E4'><b><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif'> <a href="mailto:chandra.roychoudhuri@uconn.edu" title="chandra.roychoudhuri@uconn.edu">Roychoudhuri, Chandra</a> <o:p></o:p></span></p></div><div><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif'>To:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif'> <a href="mailto:general@lists.natureoflightandparticles.org" title="general@lists.natureoflightandparticles.org">Nature of Light and Particles - General Discussion</a> <o:p></o:p></span></p></div><div><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif'>Sent:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif'> Sunday, January 29, 2017 2:23 AM<o:p></o:p></span></p></div><div><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif'>Subject:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif'> Re: [General] On photon momentum<o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;color:teal'>Hi Chip: Again, my current state of thinking is that even material particles, and hence electrons, do not possess the intrinsic property, we call MOMENTUM. This is unlike the ENERGY contained in its state of excitation (which is the cause of its existence). When v = 0, the momentum, mv, is zero. In Milikan’s oil drop experiment, he made the electron-holding oil drop stationary; so the whole drop, with the electron, had zero velocity; and hence zero momentum. Thus momentum is not an intrinsic property, even for material particles. The momentum-property becomes emergent and measurable only when one kinetic entity transfers part of its kinetic energy to increase the kinetic velocity of another particle.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;color:teal'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;color:teal'>Chandra.<o:p></o:p></span></p><p class=MsoNormal><a name="_MailEndCompose"></a><span lang=EN-US style='font-size:11.0pt;color:teal'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma",sans-serif'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma",sans-serif'> General [<a href="mailto:general-bounces+chandra.roychoudhuri=uconn.edu@lists.natureoflightandparticles.org">mailto:general-bounces+chandra.roychoudhuri=uconn.edu@lists.natureoflightandparticles.org</a>] <b>On Behalf Of </b>Chip Akins<br><b>Sent:</b> Saturday, January 28, 2017 8:54 PM<br><b>To:</b> 'Nature of Light and Particles - General Discussion'<br><b>Subject:</b> Re: [General] On photon momentum<o:p></o:p></span></p></div></div><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black'>Hi Chandra<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black'>I like your thoughts on this subject. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black'>But one issue is giving me pause. That is simply the need to have momentum circulating in the electron in order for it to possess inertial mass. And therefore, if momentum is created by the energy within the electron as it propagates (circulates) then it seems likely that momentum is also generated by the wave in space propagating linearly. Of course this may not be the case. But it seems the Occam’s preference given the situation. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black'>But it could be that momentum is only created by the motion of energy when confined such as in the electron, and that momentum is imparted to that structure simply because energy is added when it reacts with EM radiation. I have not preferred this solution because it seems more complex, and less likely, if the laws of physics are uniform for propagating energy.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black'>Chip<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'> General [<a href="mailto:general-bounces+chipakins=gmail.com@lists.natureoflightandparticles.org">mailto:general-bounces+chipakins=gmail.com@lists.natureoflightandparticles.org</a>] <b>On Behalf Of </b>Roychoudhuri, Chandra<br><b>Sent:</b> Saturday, January 28, 2017 7:08 PM<br><b>To:</b> Nature of Light and Particles - General Discussion <<a href="mailto:general@lists.natureoflightandparticles.org">general@lists..natureoflightandparticles.org</a>><br><b>Subject:</b> Re: [General] On photon momentum<o:p></o:p></span></p></div></div><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>Dear Grahame: <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>You would not like my opinion! And, I may change my opinion as I grow up learning from others!<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>As of now, my personal views are very very different from the mainstream assertions about, “indivisible photon”, its “momentum”, “spin” etc.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>To me, they are not intrinsic property of EM waves.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>They appear as measurable properties of detecting materials as they interact (respond) to the incident EM wave packets and undergo various physical changes while absorbing energy out of the propagating EM.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>For example, at the instant of emission, we certainly have a discrete quantity of energy (hv) that is released as a result of some quantum transition. That released energy “plucks” the Complex Tension Field (CTF) [or, the plenum , the ether, etc.]. The result of that “plucking” is the emergence of an EM wave packet with the frequency “v”; which then propagates away perpetually as an excitation of the CTF as long as far as the CTF exists. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>“Filtered” polarized light, interaction with<b><i> anisotropic </i></b>material medium will show preferential directional movement implying “angular momentum transfer”, which we have learned to explain as “photon” having “Angular Momentum”.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>Chandra.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'> General [<a href="mailto:general-bounces+chandra.roychoudhuri=uconn.edu@lists.natureoflightandparticles.org">mailto:general-bounces+chandra.roychoudhuri=uconn.edu@lists.natureoflightandparticles.org</a>] <b>On Behalf Of </b>Dr Grahame Blackwell<br><b>Sent:</b> Saturday, January 28, 2017 7:12 PM<br><b>To:</b> Nature of Light and Particles - General Discussion <<a href="mailto:general@lists.natureoflightandparticles.org">general@lists..natureoflightandparticles.org</a>><br><b>Subject:</b> [General] On photon momentum<o:p></o:p></span></p></div></div><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>Dear All,</span><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>[Notably Chandra & Chip],</span><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US> <o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>I'm having a bit of a problem over this question of: 'How does a photon carry momentum'? (or similar words.)</span><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>It seems to me that in order to even beginning to address this question, one needs a clear definition of 'momentum' that's applicable to the momentum carried by a photon.</span><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>I may be looking in the wrong places (if so please advise), but the only definitions of momentum that I can find either refer to 'mass' or refer to some other phenomenon which in turn refers to momentum - i.e. circular references.</span><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>If I'm going to figure, or be persuaded, how a photon carries momentum I first need to know what momentum IS in respect of a photon (yes, I know it's E/c, that's a measure it's not a definition).</span><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>Of course I'm aware of the paper "Light is heavy", but I don't feel it's appropriate just to extract from that some sort of mass-equivalence of a photon. If we do, we get the result that 'm'=E/c^2, so 'm'c = E/c - gives the right result, but appears to be some sort of convoluted self-confirmation (i.e. a circular argument dressed up in fancy clothes). It certainly doesn't DEFINE a photon's momentum, just evaluates it.</span><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US> <o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>Does anyone have a convincing definition of momentum that's applicable to a photon? One that can be used as a firm basis for theorising?</span><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>(I'd be glad if colleagues didn't use this as an excuse to yet again present their own personal theory/model - I'm looking for a definition that would be agreed by all, or at least most, physicists.)</span><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US> <o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>Thanks in anticipation,</span><span lang=EN-US><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>Grahame</span><span lang=EN-US><o:p></o:p></span></p></div><div class=MsoNormal align=center style='text-align:center'><span lang=EN-US><hr size=2 width="100%" align=center></span></div><p class=MsoNormal><span lang=EN-US>_______________________________________________<br>If you no longer wish to receive communication from the Nature of Light and Particles General Discussion List at <a href="mailto:grahame@starweave.com">grahame@starweave.com</a><br><a href="<a href="http://lists.natureoflightandparticles.org/options.cgi/general-natureoflightandparticles.org/grahame%40starweave.com?unsub=1&unsubconfirm=1">http://lists.natureoflightandparticles.org/options.cgi/general-natureoflightandparticles.org/grahame%40starweave.com?unsub=1&unsubconfirm=1</a>"><br>Click here to unsubscribe<br></a><o:p></o:p></span></p></blockquote></div></body></html>