Dualities in five dimensions and charged string solutions

Abstract

We consider an eleven dimensional supergravity compactified on K3 × T² and show that the resulting five dimensional theory has identical massless states as that of a heterotic string compactified on a specific five torus T⁵. The strong-weak coupling duality of the five dimensional theory is argued to represent a ten dimensional Type IIA string compactified on K3 × S¹, supporting the conjecture of string-string duality in six dimensions. In this perspective, we present a magnetically charged solution of the low energy heterotic string effective action in five dimensions with a charge defined on a three sphere S³ due to the two form potential. We use the Poincare duality to replace the antisymmetric two form with a gauge field in the effective action and obtain a string solution with charge on a two sphere S² instead of that on a three sphere S³ in the five dimensional spacetime. We note that the string-particle duality is accompanied by a change of topology from S³ to S² and vice versa.