Skip to content

Constraints on Light Pseudoscalars Implied by Tests of the Gravitational Inverse-Square Law

Ephraim Fischbach, Dennis E. Krause

hep-pharXiv:hep-ph/9906240

Abstract

The exchange of light pseudoscalars between fermions leads to a spin-independent potential in order g4, where g is the Yukawa pseudoscalar-fermion coupling constant. This potential gives rise to detectable violations of both the weak equivalence principle (WEP) and the gravitational inverse-square law (ISL), even if g is quite small. We show that when previously derived WEP constraints are combined with those arisingfrom ISL tests, a direct experimental limit on the Yukawa coupling of light pseudoscalars to neutrons can be inferred for the first time (gn2/4pi < 1.6 × 10-7), along with a new (and significantly improved) limit on the coupling of light pseudoscalars to protons.

Create a lesson