what is the relativistic mass of a single photon
Try using mass-energy equivilence.eNathan said:what is the relativistic mass of a single photon
nothing is too much to ask. but you might want to accept it when people answer.eNathan said:I said relavistic mass, not energy. Can someone give me an example? Or is that too much to ask?
As far as I know, units of speed are always in Meters/Second, so why are you using KM?300,000km
That's incorrect. relmass is not idetical to energy. This is equality under some specfc casesdextercioby said:Relativistic mass (for a photon,at least) IS energy.In Heaviside-Lorentz units...
How is m = p/c for a photon ??? isn't m divergent here ??? How do you renormalize this ???pmb_phy said:The relativistic mass ofa photo can be expressed in two ways one of which is m = p/c.
thats a pointless equationmarlon said:How is m = p/c for a photon ??? isn't m divergent here ??? How do you renormalize this ???
What is the second expression ???
No. I don't find it weird at all. If I see Rindler state this in no uncertain terms in his text then who am I to argue with Rindler?dextercioby said:I'm not gonna argue with you,Pete,but don't u think it's weird that u're the only person who has this opinion...?
You'd agree that a photon has momentum, 'p', would you not? You'd also agree that the speed of a photon is c, do you not? Then the relation m = p/c is well defined.marlon said:How is m = p/c for a photon ??? isn't m divergent here ??? How do you renormalize this ???
I use km because its a prettier looking number. Besides, "kilo" is just a prefix, meaning "thousand" - so km are still meters (dropping the "k" and adding 3 zeroes is not a conversion) - its a very common simplification. I would hope you could reconcile the units when plugging into the equations...eNathan said:Russ_Watters, you said
As far as I know, units of speed are always in Meters/Second, so why are you using KM?
It appears to me that Carlip is not speaking of any cases in which the energy defined mass is different than the momentum defined mass so no problem arises in that paper that I can see from a quick read. I read it closely last year and have forgotten the details.pervect said:In what manner does your webpage conflict with Carlips paper, or are you not disagreeing with Carlip?
I gave you an example of a case when E/c^2 does not equal p/v. Then you referred to Carlips paper as if it was the same topic. Carlip was speaking of the mass of closed systems. I was not. I was speaking of mass in general and in the case I gave the object is not isolated. Pertaining to the mass of a closed system Rindler statespervect said:Well, as I see it, what comes out of Carlips equations is an isotropic gravitational / inertial mass (which are the same because of the principle of equivalence) which is the same in all directions.
"..that simple formulais valid only in certain special cases, e.g. for single particles and for systems of free free [..]. It is not generally valid for constrained systems.
What part do you not understand. I'll elaborate for you. But the example is quite clear and is not lacking in details.I'm not so sure your example yields an isotropic relationship between momentum and velocity, however your calculation wasn't very detailed so it's unclear what you think.
I was addressing that one someone who knew the topic and is familiar with that stress-energy momentum tensor.pervect said:Well, an example of where your exposition could use some clarification is
"It can be shown that the momentum density as measured in S is given by .
"It can be shown that" is not a particularly strong derivation of a result, sorry :-).