Equivalence Principle for Antiparticles and its Limitations
We investigate the particle-antiparticle symmetry of the gravitationally coupled Dirac equation, both on the basis of the gravitational central-field problem and in general curved space-time backgrounds. First, we investigate the central-field problem with the help of a Foldy-Wouthuysen transformation. This disentangles the particle from the antiparticle solutions, and leads to a "matching relation" of the inertial and the gravitational mass, which is valid for both particles as well as antiparticles. Second, we supplement this derivation by a general investigation of the behavior of the gravitationally coupled Dirac equation under the discrete symmetry of charge conjugation, which is tantamount to a particle → antiparticle transformation. Limitations of the Einstein equivalence principle due to quantum fluctuations are discussed. In quantum mechanics, the question of where and when in the Universe an experiment is being performed can only be answered up to the limitations implied by Heisenberg's Uncertainty Principle, questioning an assumption made in the original formulation of the Einstein equivalence principle. Furthermore, at some level of accuracy, it becomes impossible to separate nongravitational from gravitational experiments, leading to further limitations.
U. D. Jentschura, "Equivalence Principle for Antiparticles and its Limitations," International Journal of Modern Physics A, vol. 34, no. 29, World Scientific Publishing Co. Pte Ltd, Oct 2019.
The definitive version is available at https://doi.org/10.1142/S0217751X1950180X
Keywords and Phrases
3) Gauge Group; Antiparticles; Curved Space-Time; Dirac Equation; Fundamental Symmetries; General Relativity; Inertial And Gravitation Mass; Penrose Conjecture; S O (1
International Standard Serial Number (ISSN)
Article - Journal
© 2019 World Scientific Publishing Co. Pte Ltd, All rights reserved.
01 Oct 2019
This work was supported by the National Science Foundation (Grant PHY-1710856).