Since the rate of mass loss due to stellar wind of a massive star is related to the gravitational acceleration on the surface and the luminosity of the star, thus we have to know the effects of tide, rotation and irradiation on the rate of mass loss.
The matter escaping from the surface of a star in the form of stellar wind will take away angular momentum at the same time. Thus, we have to know the relationship between the mass loss and the angular momentum loss.
We need to know how the orbital period of the binary system changes when both stars have mass loss and angular momentum loss and at the same time mass transfer occurs.
It is interesting to know, in the case that the stars have very high surface temperature and very strong radiation pressure, how their radiation affects the Roche lobe and the mass transfer.
Under certain condition, the two stars can evolve to a system with a common envelope. After the loss of the common envelope, the binary system becomes one with a very short period. It is important to determine the criteria for the two stars to evolve to have a common envelope, and the change in the orbital period of the binary system after the loss of the common envelope.
If a component evolves to a supernova, the explosion being another way for significant loss of mass and angular momentum, the questions arise whether the explosion will destroy the binary system and what the criteria are for this to occur.
When both stars have stellar wind, the collision of stellar winds will produce a shock front. The hydrodynamic theory of the shock front and the effects of the shock front should be known.
All the above problems have been discussed in the present paper.
Key words stars: massive binary system---stars: supernovae: general---stars: steller wind