Photon = quanta of energy.................... Ummm what does that really mean?

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drwayne

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<p>The idea that they were working on was that an object with a finite rest mass, like an electron, has a mass that is composed of some combination of "matter" and "matter equivalent energy".&nbsp; I have reached the edge, and somewhat beyond of what I actually remember about what they showed me way back when. (On a good day I can look at my dissertation and remember what the heck I was doing)</p><p>Wayne</p> <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

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dabiznuss

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>The idea that they were working on was that an object with a finite rest mass, like an electron, has a mass that is composed of some combination of "matter" and "matter equivalent energy".&nbsp; I have reached the edge, and somewhat beyond of what I actually remember about what they showed me way back when. (On a good day I can look at my dissertation and remember what the heck I was doing)Wayne <br />Posted by drwayne</DIV></p><p>&nbsp;All rest mass is finite so that does not make any sense at all. This matter equivalent energy for an electron would be kenetic energy, but the main point is this, the rest mass (E=MC^2) of an electron implies anti-particles in Q.M.</p> <div class="Discussion_UserSignature"> </div>

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DrRocket

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp;All rest mass is finite so that does not make any sense at all. This matter equivalent energy for an electron would be kenetic energy, but the main point is this, the rest mass (E=MC^2) of an electron implies anti-particles in Q.M. <br />Posted by dabiznuss</DIV></p><p>All rest mass is finite in the mathematical sense.&nbsp; But physicists, and Wayne is a physicist, sometimes also use the term to mean "non-zero".&nbsp; He&nbsp; was using the term in that sense in his post.&nbsp; And the matter equivalent energy for an electron is not kinetic energy.&nbsp; It is the relativistic mass which is the rest mass plus the mass increase due to motion in the reference frame in which the motion and the mass are measured.&nbsp; Furthermore the rest mass is not determined by E = Mc^2.&nbsp; In fact the M in this equation is the total mass and not just the rest mass.&nbsp; It is the rest mass only if the subject is starionary in the frame of reference used.&nbsp; Generally when one means rest mass the subscript "0" is added to "M" (M0) to denote rest mass.&nbsp; So, in relativity kinetic energy is Mc^2 - M0c^2.&nbsp; <br /></p> <div class="Discussion_UserSignature"> </div>

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dabiznuss

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>All rest mass is finite in the mathematical sense.&nbsp; But physicists, and Wayne is a physicist, sometimes also use the term to mean "non-zero".&nbsp; He&nbsp; was using the term in that sense in his post.&nbsp; And the matter equivalent energy for an electron is not kinetic energy.&nbsp; It is the relativistic mass which is the rest mass plus the mass increase due to motion in the reference frame in which the motion and the mass are measured.&nbsp; Furthermore the rest mass is not determined by E = Mc^2.&nbsp; In fact the M in this equation is the total mass and not just the rest mass.&nbsp; It is the rest mass only if the subject is starionary in the frame of reference used.&nbsp; Generally when one means rest mass the subscript "0" is added to "M" (M0) to denote rest mass.&nbsp; So, in relativity kinetic energy is Mc^2 - M0c^2.&nbsp; <br />Posted by DrRocket</DIV></p><p>For the most part i was right though correct?</p> <div class="Discussion_UserSignature"> </div>

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derekmcd

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp;All rest mass is finite so that does not make any sense at all. This matter equivalent energy for an electron would be kenetic energy, but the main point is this, the rest mass (E=MC^2) of an electron implies anti-particles in Q.M. <br /> Posted by dabiznuss</DIV></p><p>How does rest mass imply anti-particles?&nbsp; That doesn't even make sense.&nbsp; Almost all particles have an anti-particle or are their own anti-particle.&nbsp; </p><p>I don't understand your correlation between rest mass and and the implication of an anti-particle.&nbsp;</p> <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

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DrRocket

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>For the most part i was right though correct? <br />Posted by dabiznuss</DIV></p><p>No, for the most part you missed the point.&nbsp; You also at least implied unjust criticism of&nbsp;someone (drwayne) who probably has a far deeper understanding of physics than do you.&nbsp; He happens to be a real physicist.&nbsp; <br /></p> <div class="Discussion_UserSignature"> </div>

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DrRocket

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>...&nbsp; I don't understand your correlation between rest mass and and the implication of an anti-particle.&nbsp; <br />Posted by derekmcd</DIV></p><p>I think the statement was incredibly backhanded way of saying that a photon is its own anti-particle.&nbsp; <br /></p> <div class="Discussion_UserSignature"> </div>

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dabiznuss

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>No, for the most part you missed the point.&nbsp; You also at least implied unjust criticism of&nbsp;someone (drwayne) who probably has a far deeper understanding of physics than do you.&nbsp; He happens to be a real physicist.&nbsp; <br /> Posted by DrRocket</DIV></p><p>Now to sum up this conversation everyone is saying im crazy b/c rest mass plays no role With antiparticle... your wrong follow me.......... See the presence of antiparticles leads us away from a quantum theory of particles&nbsp; and into a quantum theory of fields. Just accept this for a moment. The key property of a antiparticle atleast a antiparticle of a massive particle is that they can come together and annihilate one another, their combined mass being converted into energy with E equals MC2. If enough energy is put into a small enough region than the production of particles and antiparticles can come about. Thus a relativistic theory just can't be a theory of single particles. Nor of any fixed number of particles whatever. Thus if their is potential for something to happen, it makes its contribution to the quantum state. However, the means to produce a particles mass is not, in itself sufficient for conjuring up the particle itself. Their are various additive quantum factors such as electric charge, baryon # ect. which should not change in a physical process. A charged particle out of pure energy would surely represent a violation of charge conservation. HOWEVER, WITH THE ASSUMPTION THAT FOR EVERY KIND OF PARTICLE THEIR IS A CORRESPONDING ANTIPARTICLE , FOR WHICH&nbsp; EVERY ADDITIVE QUANTUM NUMBER IS REVERSED IN SIGN A PARTICLE WITH ITS ANTIPARTICLE CAN BE CREATED OUT OF PURE ENERGY. The rest mass of the antiparticle ( rest mass being non additive) is, on the other hand the same as that of the original particle. You would need sufficient energy, atleast twice the rest mass/energy of the particle itself to create both the particle and antiparticle in the process.</p> <div class="Discussion_UserSignature"> </div>

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DrRocket

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Now to sum up this conversation everyone is saying im crazy b/c rest mass plays no role With antiparticle... your wrong follow me.......... See the presence of antiparticles leads us away from a quantum theory of particles&nbsp; and into a quantum theory of fields. Just accept this for a moment. The key property of a antiparticle atleast a antiparticle of a massive particle is that they can come together and annihilate one another, their combined mass being converted into energy with E equals MC2. If enough energy is put into a small enough region than the production of particles and antiparticles can come about. Thus a relativistic theory just can't be a theory of single particles. Nor of any fixed number of particles whatever. Thus if their is potential for something to happen, it makes its contribution to the quantum state. However, the means to produce a particles mass is not, in itself sufficient for conjuring up the particle itself. Their are various additive quantum factors such as electric charge, baryon # ect. which should not change in a physical process. A charged particle out of pure energy would surely represent a violation of charge conservation. HOWEVER, WITH THE ASSUMPTION THAT FOR EVERY KIND OF PARTICLE THEIR IS A CORRESPONDING ANTIPARTICLE , FOR WHICH&nbsp; EVERY ADDITIVE QUANTUM NUMBER IS REVERSED IN SIGN A PARTICLE WITH ITS ANTIPARTICLE CAN BE CREATED OUT OF PURE ENERGY. The rest mass of the antiparticle ( rest mass being non additive) is, on the other hand the same as that of the original particle. You would need sufficient energy, atleast twice the rest mass/energy of the particle itself to create both the particle and antiparticle in the process. <br />Posted by dabiznuss</DIV></p><p>You're getting closer.&nbsp; <br /></p> <div class="Discussion_UserSignature"> </div>

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derekmcd

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Now to sum up this conversation everyone is saying im crazy b/c rest mass plays no role With antiparticle... your wrong follow me.......... See the presence of antiparticles leads us away from a quantum theory of particles&nbsp; and into a quantum theory of fields. Just accept this for a moment. The key property of a antiparticle atleast a antiparticle of a massive particle is that they can come together and annihilate one another, their combined mass being converted into energy with E equals MC2. If enough energy is put into a small enough region than the production of particles and antiparticles can come about. Thus a relativistic theory just can't be a theory of single particles. Nor of any fixed number of particles whatever. Thus if their is potential for something to happen, it makes its contribution to the quantum state. However, the means to produce a particles mass is not, in itself sufficient for conjuring up the particle itself. Their are various additive quantum factors such as electric charge, baryon # ect. which should not change in a physical process. A charged particle out of pure energy would surely represent a violation of charge conservation. HOWEVER, WITH THE ASSUMPTION THAT FOR EVERY KIND OF PARTICLE THEIR IS A CORRESPONDING ANTIPARTICLE , FOR WHICH&nbsp; EVERY ADDITIVE QUANTUM NUMBER IS REVERSED IN SIGN A PARTICLE WITH ITS ANTIPARTICLE CAN BE CREATED OUT OF PURE ENERGY. The rest mass of the antiparticle ( rest mass being non additive) is, on the other hand the same as that of the original particle. You would need sufficient energy, atleast twice the rest mass/energy of the particle itself to create both the particle and antiparticle in the process. <br /> Posted by dabiznuss</DIV></p><p>Actuallly, the more mass/energy in a particle/anti-particle pair collision, the better the odds of the annihilation creating other more massive particles.&nbsp;&nbsp; I'm too tired at the moment to try to make sense out of the rest.</p><p>&nbsp;</p> <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

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kg

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<p>Ok,</p><p>&nbsp; I found a copy of QED at the library!&nbsp; Looks like good light summer reading...</p><p>&nbsp;HA HA HA<br /></p>

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Ranjha

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There are many types of beers (energies), and basically 3 different containers, plastic, glass and metal (Photons).&nbsp; You can shape these containers&nbsp;anyway you like (string theory,m-theory, quantum mech) or simply said&nbsp;coors bottle vs. heinkein's can.&nbsp; All in all energy has to be carried somehow and the vessel is what we are trying to find. If we run out of beer, does it really matter what the container looks like?&nbsp; Seriously I'm usually pretty pissed when I have to look at empty bottle...without beer its just as waste of metal in space. <div class="Discussion_UserSignature"> <p><font size="2" color="#cc33cc"><font color="#000000">"I'm normally not a praying man, but if you're up there, please save me Superman."<br /></font><span style="font-size:11px;color:#339999">By: Homer Simpson<br /></span></font></p> </div>

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derekmcd

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>There are many types of beers (energies), and basically 3 different containers, plastic, glass and metal (Photons).&nbsp; You can shape these containers&nbsp;anyway you like (string theory,m-theory, quantum mech) or simply said&nbsp;coors bottle vs. heinkein's can.&nbsp; All in all energy has to be carried somehow and the vessel is what we are trying to find. If we run out of beer, does it really matter what the container looks like?&nbsp; Seriously I'm usually pretty pissed when I have to look at empty bottle...without beer its just as waste of metal in space. <br /> Posted by Ranjha</DIV></p><p>Sometimes, when I have had a few too many beers, I compose posts that resemble this one.</p> <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

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UncertainH

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<p>Is this right ?&nbsp;</p><p>Photon has no mass</p><p>Photon has no kinetic energy but has direction in space and we perceive it to travel at the speed of light</p><p>Photon has energy potential and is stable in the Quantum vacuum</p><p>It doesn't accelerate from rest to the speed of light it starts its life at that speed</p><p>Therefore the speed is a result of the quantum vacuum seeking to annihilate the photon, negative at the front, positive at the back and it follows a null geodesic. The response time of the vacuum gives it its perceived speed which might help explain how recent experiments have managed to "slow light down" in a supercooled condensate. Perhaps that slows down the local response time of the quantum vacuum?</p><p>&nbsp;</p>

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DrRocket

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Is this right ?&nbsp;Photon has no mass</p><p><font color="#0000ff">The photon has no rest mass.&nbsp; But it does have energy which is dependent on the frequency which is dependent on the frame of reference. </font>&nbsp;</p><p>Photon has no kinetic energy but has direction in space and we perceive it to travel at the speed of light</p><p><font color="#0000ff">The photon has energy given by Planck's constant times the frequency.&nbsp; Whether you call that kinetic energy or not is a matter of semantics.&nbsp; Not only do we perceive a photon to travel at the speed of light, it does in fact travel at the speed of light, and it is light.</font></p><p>Photon has energy potential and is stable in the Quantum vacuum</p><p><font color="#0000ff">The photon is stable and it has energy.&nbsp; See previous discussion&nbsp;for potential vs kinetic enregy. </font>&nbsp;</p><p>It doesn't accelerate from rest to the speed of light it starts its life at that speed</p><p><font color="#0000ff">The photon has no rest mass, and hence exists only in motion at the speed of light.</font></p><p>&nbsp;</p><p>Therefore the speed is a result of the quantum vacuum seeking to annihilate the photon, negative at the front, positive at the back and it follows a null geodesic. The response time of the vacuum gives it its perceived speed which might help explain how recent experiments have managed to "slow light down" in a supercooled condensate. Perhaps that slows down the local response time of the quantum vacuum?</p><p><font color="#0000ff">It is rather hard to see the logic behind this assertion.&nbsp; If you have a justification for these statements please present them.&nbsp; This sounds like pure speculation, and not very clearly defined speculation at that.&nbsp; The slowing down of light as it is transmitted through a material is well-known and is reflected in the index of refraction for various materials.&nbsp; In reality the process is one of many absorptions and re-emissions in the material and not just the slowing down of individual photons.&nbsp; </font></p><p><br />Posted by UncertainH</DIV><br /></p> <div class="Discussion_UserSignature"> </div>

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mickeyl

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<p>&nbsp;<font size="2">Uncertain said:</font></p><p><font size="2">"The response time of the vacuum gives it its perceived speed which might help explain how recent experiments have managed to "slow light down" in a supercooled condensate. Perhaps that slows down the local response time of the quantum vacuum?"</font></p><p><font size="2">---------------</font></p><p><font size="2">Perhaps light should slow down in a supercooled environment, or in an absolute zero environment, because there is an absence of dark-energy-radiation in an&nbsp;absolute-zero environment.&nbsp;&nbsp;&nbsp; </font></p><p><font size="2">-------------------------------------------------------------------------------------------</font></p><p><font size="2" color="#0000ff">DrRocket said:&nbsp;</font></p><p><font size="2" color="#0000ff">"The photon has energy given by Planck's constant times the frequency.&nbsp; Whether you call that kinetic energy or not is a matter of semantics.&nbsp; Not only do we perceive a photon to travel at the speed of light, it does in fact travel at the speed of light, and it is light."</font></p><p><font size="2" color="#0000ff">---------------</font></p><p><font size="2" color="#0000ff">If light has a propulsion mechanism, it must also have super-strong brakes to alight so softly on the eye of a human-being.</font></p><font size="2" color="#0000ff">-------------------------------------------------------------------------------------------</font><font color="#0000ff"><font size="2"> </font><p><font size="2" color="#0000ff">Also:&nbsp; "The photon has no rest mass, and hence exists only in motion at the speed of light."</font></p><p><font size="2">--------------</font></p><p><font size="2">So, you're saying the photon has locomotion energy, that allows it to travel unerringly in a straight line (without wavering, or changing direction) throughout the universe, for potentially 13.7 billion years?&nbsp; Sounds like a strong photon.</font></p></font>

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UncertainH

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<p>Following up on "Therefore the speed is a result of the quantum vacuum seeking to annihilate the photon".</p><p>&nbsp;Yes it is speculation. What I'm thinking is that supposedly in a quantum vacuum there are constant fluctuations and energy can appear and then quickly disappear because the anti-particle emerges and they destroy each other and the energy in the vacuum remains stable. This action must take a finite amount amount time to occur. Someone earlier in this thread suggested that a photon is its own anti-particle which doesn't make much sense to me. But if the response to the presence of energy by the QV is to create the energy counterpart how does the QV respond when a stable particle like the photon is present. It could create an 'anti-photon' but that wouldn't annihilate the photon because the photon is stable and cannot be destroyed. So lets say that the QV tries anyway, creates the antiphoton and they move towards each other but the photon remains so it happens continuosly. When this is superimposed on our 3D world it appears that the photon is moving. In the frame of reference of the photon, it is not moving at all it is just a bundle of stable energy.</p><p>&nbsp;</p><p>?</p>

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