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bgq
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Hi,
Is the mass of the photon exactly zero, or it has some little mass?
Thanks in advance.
Is the mass of the photon exactly zero, or it has some little mass?
Thanks in advance.
What if the photons are really have some mass and their speed is slightly less than c; in such case, c may be not called speed of light, but a universal constant. I have read that relativity will not be affected by this.mathman said:Current theory says anything with mass cannot travel at the speed of light. If photons had mass it would mean photons cannot travel as fast as photons.
andrien said:an indirect way to ask this question is how much valid is the inverse square relationship
Massless quanta mediate forces (interactions) which scale (in 3+1 dimensions) as 1/r2; in the case of photons this applies to the Coulomb force of an electric field.bgq said:I really can't see the connection, will you clarify this to me please.
bgq said:Hi,
Is the mass of the photon exactly zero, or it has some little mass?
Thanks in advance.
bgq said:Hi,
Is the rest mass of the photon exactly zero, or it has some little mass?
Thanks in advance.
here is a link which can clarify more of it ,it seems that the account is same as that given in beginning of jackson's book.there is numerous data on upper limit of mass of photon.bgq said:I really can't see the connection, will you clarify this to me please.
that link is not working so try thisandrien said:here is a link which can clarify more of it ,it seems that the account is same as that given in beginning of jackson's book.there is numerous data on upper limit of mass of photon.
"www.princeton.edu/~romalis/PHYS312/.../TuCoulomb.pdf"
BrettJimison said:energy = mass.
If photons have energy, then they have mass.
But then again, Einstein also said that anything with mass can't travel at the speed of light..hmmmm
Well... current theory (relativity) says that there is a constant speed which is an upper limit for massive particles, and that all massless particles travel at that constant speed.mathman said:Current theory says anything with mass cannot travel at the speed of light. If photons had mass it would mean photons cannot travel as fast as photons.
Meselwulf said:We are missing a conversion factor, the speed of light squared as a coefficient on the mass, and energy equivalent like this does not actually mean that mass is energy per se, rather two different forms of each other.
This is what needs to be kept in mind.
The rest mass of a photon is zero or it is very very small... ridiculously small... something like [tex]10^{-51}[/tex] kg.
Are you trying to say that in a medium photons have speed less than c (refractive index).then it is not right because the phase velocity of light may seem to be c/n but photons always travel with speed C.It is the electric field of light which causes the shaking of electrons of the medium so they emit their own radiation (radiation of protons can be neglected because of their mass) which when combined with original one gives a phase shift which can be described by giving light a speed C/n.Meselwulf said:However... photons under the right kind of circumstances (ie. the medium) can make a photon behave as though it has a mass (rest).
A photon is a fundamental particle of light that carries electromagnetic energy. It has zero mass and travels at the speed of light.
Yes, according to the theory of relativity, the mass of a photon is zero. This has been confirmed by numerous experiments and is a fundamental property of photons.
Although photons have no mass, they do have energy due to their wave-like nature. The energy of a photon is directly proportional to its frequency, which determines the color of light.
Although photons have no mass, they do have energy and momentum. This allows them to be affected by gravity, as gravity can distort the path of light.
No, the mass of a photon is a fundamental property and cannot change. However, the energy and frequency of a photon can change, depending on the medium it is traveling through.