  The approach to the theory of a relativistic random process is considered by
the path integral method as Brownian motion taking into account the boundedness
of speed. An attempt was made to build a relativistic analogue of the Wiener
measure as a weak limit of finite-difference approximations. A formula has been
proposed for calculating the probability particle transition during
relativistic Brownian motion. Calculations were carried out by three different
methods with identical results. Along the way, exact and asymptotic formulas
for the volume of some parts and sections of an N-1-dimensional unit cube were
obtained. They can have independent value.
