1961/07/01 by G. Kalman · 3 citations
Physics and Astronomy · Mathematics · #Quantum and Classical Electrodynamics #Relativity and Gravitational Theory #Algebraic and Geometric Analysis
paper · doi:10.1103/physrev.123.384
openalex publication_date 1961/07/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/04/04
A covariant Lagrangian formalism is put forward with an explicit variation of the proper time in the action functional. This approach conforms with the geometrical interpretation in space-time. A general equation of motion is derived, which is not identical with the Euler-Lagrange equation. Momentum and mass are unambiguously defined through the requirement of translational invariance. The rest mass is constant in the special case of electromagnetic field only. A conservation law for the combination of the momentum and the energy momentum-tensor of the free field is derived. No satisfactory Hamiltonian formalism can be established within the framework of the formalism.