Retrograde polish doughnuts around boson stars

We investigate polish doughnuts with a uniform constant specific angular momentum distribution in the space-times of rotating boson stars. In such space-times thick tori can exhibit unique features not present in Kerr space-times. For instance, in the context of retrograde tori, they may possess two centers connected or not by a cusp. Rotating boson stars also feature a static ring, neither present in Kerr space-times. This static ring consists of static orbits, where particles are at rest with respect to a zero angular momentum observer at infinity. Here we show that the presence of a static ring allows for an associated static surface of a retrograde thick torus, where inside the static surface the fluid moves in prograde direction. We classify the retrograde Polish doughnuts and present several specific examples.

Automated summary

The study investigates the unique features of Polish doughnuts in the space-times of rotating boson stars, showing the possibility of static surfaces for retrograde thick tori with the presence of a static ring. This characteristic is not present in Kerr space-times.