Recent content by martindrech

Simply because is easier to look (using fourth-vectors) at the equations for the potentials instead of the equation for the fields.

Is it enough to see the covariance of the wave equation the fourth-vector potential (\phi, \bar{A}) satisfy? I mean, is this enough to prove the covariance of Maxwell equations? The equation would be ∂_{\mu}∂^{\mu}A^{\nu} =\frac{4\pi}{c} J^{\nu}

I´ve read that a temperature of 100 pK has been reached by scientists. But how can they measure such a low temperature? And achieve that level of accuracy?