(De)quantization of black hole charges

TL;DR

This paper explores how black hole charges are quantized in CP-conserving theories and how CP violation can lead to dequantization, affecting the existence of purely magnetic black holes.

Contribution

It introduces the concept of dequantization of black hole charges in CP-violating scenarios and provides concrete examples illustrating this phenomenon.

Findings

Magnetic and electric charges are quantized in CP-conserving theories.

CP violation can cause dequantization, preventing pure magnetic black holes.

Examples include charge induction via pion fields and massive spin-two fields.

Abstract

We argue that magnetic and electric charges of the Reissner-Nordstrom black hole are quantized in CP conserving theories. Dequantization phenomenon occurs when CP is broken either explicitly or effectively, and, as a result, pure magnetic black holes are not possible. Two examples illustrating this phenomenon are discussed. One is the electric charge induced by the neutral pion field in a magnetically charged black hole, and another is the electric charge induced due to the massive spin-two field emerging from possible higher curvature terms.