Experimental evidence of Gauss's law in electrodynamics?

AI Thread Summary
Gauss's law can be derived from Coulomb's law in electrostatics, but its validity in non-static cases requires experimental evidence since Coulomb's law does not apply. Current experiments suggest that Gauss's law has stronger empirical support than Coulomb's law, particularly in testing the exponent 2 in Coulomb's law, which relates to photon mass limits. A recent seminar raised questions about the validity of divE=0 in pure void, suggesting that reference frames might affect this principle, though the logic remains unclear. The discussion highlights the need for experiments conducted in non-lab frames to further investigate these concepts. Overall, the relationship between Gauss's law, Coulomb's law, and experimental evidence continues to be a significant topic in electrodynamics.
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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 In this case we know columb's law is no longer valid, so we need experimental evidence to justify Gauss's law, am I correct?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?
 
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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/> and go to the photon to see recent experimental tests.
 
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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)
 
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