Genesis of spiral galaxies

TL;DR

This paper proposes a novel mechanism where a lightweight black hole's capture by a primordial gas cloud leads to the formation of spiral arms in galaxies, highlighting the role of black hole dynamics in galaxy formation.

Contribution

It introduces a new model linking black hole capture and gas dynamics to the genesis of spiral galaxy structures, emphasizing the influence of dark matter.

Findings

Black hole capture induces spiral arm formation.

Accretion disc formation transfers orbital momentum.

Spiral arms originate from sound wave fronts in gas.

Abstract

Enigmatic spiral structure of many galaxies and its huge orbital momentum originated due to the capture of lightweight bare black hole by gravity of heavy primordial gas cloud at large impact parameter. The rotating of black hole caused the formation of accretion disc from the cloud and the transfer of orbital momentum to the disc, while during the fall to the center of mass, the spiral trace of black hole in the disc did create the spiral front line of sound waves in the gas, that further evolved into the stellar spiral arms. This mechanism opens the way to study features of spiral galaxy formation, say, an influence and a significance of dark matter in this process.