Time-symmetric relativistic and quantum theories. 1. Time-symmetric theories of special and general relativity
In relativistic theory, particles have negative energy pairs, which were considered unphysical, but Dirac (1930) linked them with antiparticles, Zisman (1940) and Stueckelberg (1941) showed that they formally evolve backward in ordinary time t, and Feynman (1949) developed a covariant diagram technique based…