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EroticNirvana
Mar13-06, 09:58 AM
Hi I need a good example of a four potential that yields a photon

marlon
Mar16-06, 08:32 AM
Hi I need a good example of a four potential that yields a photon

The gauge field of the EM-interaction.

marlon

edit : let me ask you this question : "Do you know why a quantumfield yielding a photon must be a 4-field ?"

EroticNirvana
Mar20-06, 12:26 PM
of course gauge invariance. The e-m exhibits U(1) gauge invariance. (but feel free to remind me about anything of this)

A four potential looks like this: a(q) +b(x)i + c(y)j+ d(z)k
I´m just too lazy to calculate them and have never really done it, but I need to know an example of a(q), b(x), c(y), d(z) for a photon.


The gauge field of the EM-interaction.

marlon

edit : let me ask you this question : "Do you know why a quantumfield yielding a photon must be a 4-field ?"

EroticNirvana
Mar22-06, 10:49 AM
ok, can´t find the edit button, but of course functions a, b, c, d in the last message depend on more than one variable (perhaps all q, x, y, z).