# Nonvanishing magnetic field in pure electrostatic systems at rest in the curved space-time of Earth

## TL;DR

This paper demonstrates that electrostatic systems at rest on Earth's curved spacetime can generate a nonvanishing magnetic field of purely geometric origin, impacting precision measurements like EDM searches.

## Contribution

It reveals the existence of a geometric magnetic field in electrostatic systems on Earth, which cannot be shielded and affects sensitive EDM experiments.

## Key findings

- Electrostatic systems exhibit a nonvanishing magnetic field due to spacetime curvature.
- This magnetic field cannot be eliminated by magnetic shielding.
- Implications for EDM experiments in electric storage rings and neutron EDM tests.

## Abstract

Solutions of the Maxwell equations for electrostatic systems at rest on the rotating Earth's surface are shown to exhibit a nonvanishing magnetic field despite zero electric currents in the system. Such a field is of pure geometric origin, and in contrast to the conventional magnetic field of the Earth it can not be screened away by magnetic shielding. A practical significance of this magnetic field is that its EDM-like background signal would persist in the much discussed searches for the EDM of charged particles of magic energy trapped in all electric storage rings, as well as in the neutron EDM experiments.