Coupling of Coaxial Roton Spiral Waves

In this section we derive a compact coupling model for self-stable coaxial cylindrical (spiral) LEDO-waves, as they occur in the Roton-Model. We consider two Roton-spiral waves located on different ring radii, and compute how strongly the outer spiral wave can couple inward to the inner spiral wave. We also identify the geometric and frequency conditions for forward coupling, resonance, and the possibility of a backward-running component.

Black holes

Why does gravity escape a black hole? Generally it does not, but.

This would be the classical view: Because this is a static property of space-time. It is called energy-density. So fields can not be faster than light, but gravity can? Yes, this is how Einstein calculated as well.