Discrete Velocity Models

In the classical description, a gas is made of atoms and molecules, but when MAXWELL and BOLTZMANN developed the basic ideas for the kinetic theory of gases, they imagined a gas made of particles with no internal structure. In celestial mechanics, all planets are assumed to have spherical symmetry so that the gravitational field created outside is the same as that of a point mass at its centre, and the gravitational forces on another planet produce only a resulting attraction of its centre and no torque, so that there is no change in the angular momentum of the planets, and one neglects them. It would be different for planets with a magnetic field, because electromagnetism would have to be taken into account, and in a close encounter planets could exchange angular momentum through electromagnetic interaction. Actually, ALFVÉN observed in the 1970s that some of what is observed in the cosmos should be explained by electromagnetic effects, but those who adhere to the dogma of gravitation cannot learn about electromagnetism, and they prefer to invent dark matter, dark energy, dark fields, and so on, in order to avoid questioning their dogma. The same problem occurs concerning the 19th century ideas in kinetic theory, that there has been enough evidence to show that they are wrong, but most people want to stick to them. The ideas of POINCARÉ about relativity have pointed out that there are no instantaneous forces at a distance, and his reason was that one cannot define instantaneity and that interaction between particles must be transmitted by a field, at the velocity of light, but a more compelling reason has come out from quantum mechanics, despite its dogmatic errors, that at a microscopic level there are only waves and no particles, so that the classical ideas about near collisions involving only two particles feeling a force at a distance should be rejected as a naive 19th century point of view.