Classical Physics physics.class-ph

In a hollow metal sphere, light waves can freeze into stationary patterns, like frozen ripples on a pond. But among all possible shapes, one is peculiar: it has zero frequency, and the fields vanish, leaving only a mathematical trace. For a long time, this invisible 'ghost' confused physicists when

New work exposes a gap: the effect of charge on gravity has never been systematically studied. The authors predict a tiny change in acceleration depending on the charge-to-mass ratio and propose modifying a torsion balance to illuminate this blind spot for the first time. Surprise: for the electron,

An old idea gets a fresh breath: atoms can be described without mysterious quanta if we consider that even absolute emptiness is threaded with an electromagnetic hum. This hum, like an invisible surf, constantly nudges the electron and keeps it from crashing into the nucleus. Scientists added near-l

By comparing the redshift and blueshift of light from two symmetric points in orbit, scientists can calculate the mass and distance to a black hole. Gravity distorts the color, but a pair of beams allows its influence to be isolated. The method works even if the system is moving.