# Experimental evidence of Gauss's law in electrodynamics?

1. Feb 17, 2010

### kof9595995

In electrostatic case, Gauss's law can be derived from Columb's law, so we can regard experimental evidence for Columb's law as evidence of Gauss's law. But what about non-static case? In this case we know columb's law is no longer valid, so we need experimental evidence to justify Gauss's law, am I correct? If so, could you guys show me some of such experiments?

2. Feb 17, 2010

### clem

Actually, the experimental evidence is stronger for Gauss than for Coulomb.
Since both depend on the exponent 2 in Coulomb's law, testing Gauss is used as a test for that exponent. Today, most tests are interpreted as a limit on the mass of the photon, since zero mass leads to the 1/r^2. you could go to <http://pdg.lbl.gov/> [Broken] and go to the photon to see recent experimental tests.

Last edited by a moderator: May 4, 2017
3. Feb 17, 2010

### kof9595995

Emm, true.
Actually yesterday an Italian guy came to our school and gave a seminar, discussed what can we get for EM wave if divE=0 is not necessarily true in pure void (He's a mathematician not physicist). I just didn't get the point, because i think divE=0 is well examined by experiments, and he mentioned it might not be true because we couldn't choose a reference frame relatively at rest to the EM wave(i might not hear him very clearly, but definitely something involving reference frame), but I couldn't see the logic.....Do you guys understand?
Anyway that reminds me to check if there's any experiment done in a non-lab frame (relatively moving w.r.t earth)