On the Fission Theory of Binary Stars

The fission theory is reformulated so as to be independent of the action of viscosity. It is found that this results in evolution not along the Jacobi series, but along a similar series of ellipsoids, the lower seff-adjoint series of Riemann. The evolution takes place on the contri'ction timescale t , even in the neighborhood of points where a dynamical instability sets in. This circumstance frees the present formulation from the objection, frequently raised against the classical formulation, connected with the occurrence of a dynamical, or ordinary, instability of the ellipsoidal series under disturbances belonging to the third ellipsoidal harmonics. Certain other objections that have been raised against the fission theory are also reconsidered.