TY - JOUR

T1 - It is hard to learn how gravity and electromagnetism couple

AU - Chu, Yi Zen

AU - Jacobs, David M.

AU - Ng, Yifung

AU - Starkman, Glenn D.

PY - 2010/9/16

Y1 - 2010/9/16

N2 - We construct the most general effective Lagrangian coupling gravity and electromagnetism up to mass dimension 6 by enumerating all possible nonminimal coupling terms respecting both diffeomorphism and gauge invariance. In all, there are only two unique terms after field redefinitions: one is known to arise from loop effects in QED, while the other is a parity-violating term which may be generated by weak interactions within the standard model of particle physics. We show that neither the cosmological propagation of light nor, contrary to earlier claims, solar system tests of general relativity are useful probes of these terms. These nonminimal couplings of gravity and electromagnetism may remain a mystery for the foreseeable future.

AB - We construct the most general effective Lagrangian coupling gravity and electromagnetism up to mass dimension 6 by enumerating all possible nonminimal coupling terms respecting both diffeomorphism and gauge invariance. In all, there are only two unique terms after field redefinitions: one is known to arise from loop effects in QED, while the other is a parity-violating term which may be generated by weak interactions within the standard model of particle physics. We show that neither the cosmological propagation of light nor, contrary to earlier claims, solar system tests of general relativity are useful probes of these terms. These nonminimal couplings of gravity and electromagnetism may remain a mystery for the foreseeable future.

UR - http://www.scopus.com/inward/record.url?scp=78650967861&partnerID=8YFLogxK

U2 - 10.1103/PhysRevD.82.064022

DO - 10.1103/PhysRevD.82.064022

M3 - 期刊論文

AN - SCOPUS:78650967861

VL - 82

JO - Physical Review D - Particles, Fields, Gravitation and Cosmology

JF - Physical Review D - Particles, Fields, Gravitation and Cosmology

SN - 1550-7998

IS - 6

M1 - 064022

ER -