Gravitational Experiments with a Cylindrical Galaxy
Roger W. Hockney · The Astrophysical Journal · 1967
A collisionless computer model is used to perform gravitational experiments with a two-dimensional galaxy. The motion of 2000 rods of mass is computed step-wise in time as they move according to Newton's laws of motion in their mutual gravitational field. The results are displayed as a movie and show the types of galactic structure that can arise from purely gravitational effects. A galaxy with insufficient rotation to balance gravitational attraction is seen to collapse and form filamentary condensations, then to change through structures similar to the "spirals" and "barred spirals," and finally to settle down to a cylindrical form reminiscent of an "elliptical" galaxy.