Given a particle in Euclidean space, a central force is a force that points toward or away from the origin and depends only on the particle’s distance from the origin. If the particle’s position at ...

Math and physics explain the anguish of a golf ball that zings around the rim of the hole instead of falling in.

We measure the “warmness” of the dark matter, i.e. the comoving root-mean-square thermal velocity v hrms (1) , with nearly 3000 spiral galaxy rotation curves in the ...