Twin Paradox and the Method of Experimental Research

Twin paradox is proposed by a French scientist P.Langevin.Einstein held that the issue could not be solved with special theory of relativity,and general theory of relativity need to be applied.But he did not give a complete solution.In China Professor Wang Yongjiu′s solution to this issue is one of the most appropriate.However,Professor Wang′s solution has a premise:the earth is the inertial reference frame.This paper analyzes this hypothesis,suppose that if the spacecraft and the sun are synchronous,Professor Wang′s hypothesis can also be applied to spacecraft,therefore twin paradox is not solved completely.Based on analysis of the cause of paradox in theory of relativity,this paper obtained Applicable Conditions of Relativity.Most of the paradoxes in relativity can be explained with this condition and experimental methods are provided to test the theory.Those experimental methods are achievable in current technical conditions,hence twin paradox problem can be solved by experiments to the core.