Einstein-Maxwell gravitational instantons and five dimensional solitonic strings

TL;DR

This paper explores four-dimensional Einstein-Maxwell gravitational instantons, their moduli space, and their lift to five-dimensional solitonic strings, revealing new solutions with specific topologies and properties.

Contribution

It introduces new multicentred instanton solutions without topology restrictions and demonstrates their lift to regular five-dimensional solitonic strings carrying null momentum.

Findings

Classified instantons asymptotic to various geometries.

Analyzed the classical metric on the instanton moduli space.

Constructed multi 'solitonic string' solutions in 5D supergravity.

Abstract

We study various aspects of four dimensional Einstein-Maxwell multicentred gravitational instantons. These are half-BPS Riemannian backgrounds of minimal N=2 supergravity, asymptotic to R^4, R^3 x S^1 or AdS_2 x S^2. Unlike for the Gibbons-Hawking solutions, the topology is not restricted by boundary conditions. We discuss the classical metric on the instanton moduli space. One class of these solutions may be lifted to causal and regular multi `solitonic strings', without horizons, of 4+1 dimensional N=2 supergravity, carrying null momentum.