String dynamics near a Kaluza-Klein black hole

TL;DR

This paper investigates the classical dynamics of strings near Kaluza-Klein black holes, deriving solutions for string motion in electrically and magnetically charged cases and analyzing how the Kaluza-Klein radius evolves over time.

Contribution

It provides explicit solutions to string equations of motion near Kaluza-Klein black holes, considering both charge types and their effects on the Kaluza-Klein radius.

Findings

Kaluza-Klein radius increases with time for electrically charged black holes.

Kaluza-Klein radius decreases with time for magnetically charged black holes.

Solutions are expressed in terms of the world-sheet coordinate τ.

Abstract

The dynamics of a string near a Kaluza-Klein black hole are studied. Solutions to the classical string equations of motion are obtained using the world sheet velocity of light as an expansion parameter. The electrically and magnetically charged cases are considered separately. Solutions for string coordinates are obtained in terms of the world-sheet coordinate $\tau$. It is shown that the Kaluza-Klein radius increases/decreases with $\tau$ for electrically/magnetically charged black hole.