Question

How massive is photons?

Answer 1

How are photons often drawn?

Answer 2

\(\gamma\) inside the customary little ball

Answer 3

@IrishBoy123 thank you

Answer 4

photon is a massless particle, even if the current theory doesn't deny the hypothesis for a not massless photon. Current researches give this limit for photon mass:

\[\Large {m_\gamma } \leqslant {10^{ - 48}}{\text{grams}}\]

Answer 5

thanks @Michele_Laino

Answer 6

:) @rvc

Answer 7

@Michele_Laino Hey, how would you even measure that, or is that one of the results from the relativity equations?

Answer 8

i reckon this is a great answer - there's some physics wordplay going on here

https://www.physicsforums.com/threads/do-photons-have-mass.511175/

Answer 9

no, many experiments are made in order to establish the mass of the photon

Answer 10

here is a reference about an experiment on the photon mass:
P.A. Franken and G.W. Ampulski, Phys. Rev. Letters 26, 115 (1971)

Answer 11

subsequently many others experiments are made starting from the Proca equations, which substitute the Maxwell equations, if the photon is not massless. Those equations can be derived by the Proca Lagrangian:

\[\Large {L_{{\text{Proca}}}} = - \frac{1}{{16\pi }}{F_{\alpha \beta }}{F^{\alpha \beta }} + \frac{{{\mu ^2}}}{{8\pi }}{A_\alpha }{A^\alpha } - \frac{1}{c}{J_\alpha }{A^\alpha }\]

Answer 12

where:
\[\Large {F_{\alpha \beta }},\;{A_\alpha },\;{J_\alpha }\]
are the electromagnetic tensor, quadrivector potential, and quadrivector density current respectively, furthermore:
\[\Large \mu = \frac{{{m_{ph}}c}}{\hbar }\]
m_ph is the photon mass

Answer 13

I have written a scientific paper on the photon mass, and I have showed that if the photon has a mass, then another quantum action has to exist. nevertheless my article is unpublished

Answer 14

Awesome, thanks for the information guys! I also read the link you gave @IrishBoy123 thank you.

@Michele_Laino Is it possible I could get a copy, I would like to give it a read, sounds very interesting.

Thanks again :)

Answer 15

yes! I can attach my paper as PDF file here

Answer 16

@Michele_Laino you're an awesome resource in these parts!

Answer 17

thanks! :) @IrishBoy123

Answer 18

That would be great! Haha yes Michele is!

Answer 19

ok! please wait a moment, since I have to retrieve my article @Astrophysics

Answer 20

No problem! Take your time :)

Answer 21

ok!

Answer 22

here is my article:

Answer 23

Awesome, thank you! I will read over it and if I have questions I will message you!

Answer 24

ok! :)

Answer 25

Thanks again

Answer 26

:)