In a recent blog
, Stephen Wolfram discusses the idea of what he calls "gravitational crystals." These are infinite arrays of gravitational bodies in periodic motion. Two animations
of mesmerizing movements of points were given
as examples of what gravitational crystals could look like, but no explicit orbit calculations were given.
In this blog, I will carefully calculate explicit numerical examples of gravitational crystal movements. The "really" in the title should be interpreted as a high-precision, numerical solution to an idealized model problem. It should not be interpreted as "real world." No retardation, special or general relativistic effects, stability against perturbation, tidal effects, or so on are taken into account in the following calculations. More precisely, we will consider the simplest case of a gravitational crystal: two gravitationally interacting, rigid, periodic 2D planar arrays embedded in 3D (meaning a 1/distance2 force law) of masses that can move translationally with respect to each other (no rotations between the two lattices). Each infinite array can be considered a crystal, so we are looking at what could be called the two-crystal problem (parallel to, and at the same time in distinction to, the classical gravitational two-body problem).