Directional Quantum Singularities in Curzon Spacetime

TL;DR

This paper investigates how quantum scalar fields perceive singularities in the Curzon spacetime, revealing that some classical singularities are smoothed out quantum mechanically, while others persist.

Contribution

It applies the scalar quantum probe method to the Curzon spacetime, demonstrating the regularization of the classical singularity in uncharged cases and its persistence in charged cases.

Findings

Uncharged Curzon singularity becomes regular quantum mechanically.

Charged Curzon spacetime retains singularity quantum mechanically.

Different charged versions share similar quantum singularity behavior.

Abstract

The scalar quantum probe method developed by Horowitz and Marolf is applied to the cylindrically symmetric Curzon solution. The main cause for choosing the Curzon solution is that it is the best known example that exhibits directional singularity. Interestingly the singularity at $r=0$, for the uncharged Curzon spacetime, which is classically very strong with a divergence rate of the order $\frac{1}{r^{10}}$ becomes regular when examined using scalar quantum field. The charged Curzon spacetime, however, due to the emergence of a second singularity off the $r=0$ singularity does not regularize quantum mechanically. All three different charged versions, i.e. electric, magnetic and dyonic share the same feature.