Coulomb Gauge vs. Lorentz Gauge transformation

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To determine if a transformation is a Coulomb or Lorentz gauge, one method involves deriving the electric field from the given scalar and vector functions. If the electric field resembles a static Coulomb field, it indicates a Coulomb gauge; otherwise, it is a Lorentz gauge. The discussion emphasizes that Coulomb and Lorentz gauges are not transformations but conditions on the four-potential, which can be verified by checking if the divergence of the four-potential equals zero for the Lorentz gauge. The process involves taking the derivative of the four-potential. Understanding these concepts is crucial for gauge theory in electromagnetism.
kthouz
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Given a set of a scalar function V and a vector function, how does one recognize that it is a coulomb gauge or lorentz gauge transformation?
Actually there is a method that i use but i am not sure if it is always true:
what i do is to make an electric field (from that set and using known gauge transformation) and see if it has the form a coulomb electric field (static field). If it does i conclude that it is a coulomb gauge, else it is a Lorentz gauge.
Am i right?
 
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You can find descriptions of the Coulomb and Lorentz gauge conditions here:

http://en.wikipedia.org/wiki/Gauge_fixing

(and probably in any E&M textbook at the intermediate level or above.)

If this isn't what you're looking for, please clarify...

Also note that there is in principle an infinite set of possible gauges, of which Coulomb and Lorentz are only two.
 
The Coulomb and Lorenz gauges are not gauge transformations. They are auxiliary conditions on the four-potential that we may choose because of the fact that there is gauge freedom. If you have a given four-potential Aµ, and you want to check if it satisfies the Lorenz gauge, all you have to do is show that ∂µAµ = 0.
 
Exactly. And how do you show this?
This is my question ...
 
You take the derivative.
 
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