Probing the two-neutrino exchange force using atomic parity violation

TL;DR

This paper investigates the two-neutrino exchange force as a long-range parity-violating interaction within atomic physics, calculating its effects on atomic parity violation experiments, notably in hydrogen, and discussing potential for future detection.

Contribution

It introduces the two-neutrino exchange force as the largest parity-violating long-range force in the Standard Model and provides explicit calculations for atomic systems.

Findings

The two-neutrino force is too small to detect in hydrogen with current technology.

The approach can be applied to other experimental setups with larger long-range parity violation.

This force represents the dominant parity-violating long-range interaction in the Standard Model.

Abstract

The exchange of two neutrinos at one loop leads to a long-range parity-violating force between fermions. We explore the two-neutrino force in the backdrop of atomic physics. We point out that this is the largest parity-violating long-range force in the Standard Model and calculate the effect of this force in experiments that probe atomic parity violation by measuring optical rotation of light as it passes through a sample of vaporized atoms. We perform explicit calculations for the hydrogen atom to demonstrate this effect. Although we find that the effect is too small to be observed in hydrogen in the foreseeable future, our approach may be applied to other setups where long-range parity violation is large enough to be probed experimentally.