The mass and velocity formula of relativity is m = m0/(v/u-1) = m0/√ (1-v2/C2).
Derivation of the relationship between mass and velocity: the S' system (in which the ball is stationary and the mass m0) moves along the X-axis with the velocity V relative to the S system (in which the ball is stationary and the mass m0). Let the mass of a' relative to s' system be m, and according to the symmetry of the system, the mass of a relative to s' system is also m. ..
General relativity includes the following basic assumptions:
1, generalized relativity principle (generalized covariant principle): Any physical law should be expressed by physical quantities independent of the reference system. Described in geometric language, any space-time quantity appearing in physical laws should be the scale of space-time, or a physical quantity derived from it.
2. Einstein's field equation (see the item of general relativity for details): It specifically expresses the influence of matter (dynamic tensor) in space-time on space-time geometry (function of curvature tensor), in which the requirement of corresponding dynamic tensor (its gradient is zero) includes the above-mentioned motion equation of inertial moving objects.
In essence, all physical problems involve the question of which view of time and space to adopt. In classical physics before the twentieth century, people adopted Newton's absolute view of time and space. Relativity has changed this view of time and space, which leads people to rewrite the formula of classical physics according to the requirements of relativity, so that it has Lorentz covariance required by relativity, rather than Galileo covariance.