# About a class of exact string backgrounds

Source: [About a class of exact string backgrounds](<https://www.sota2.com/research/paper/68fa31e11e209131ce882beb>)

Collection index: [llms.txt](<https://www.sota2.com/research/llms.txt>)

Data updated: 2025-10-24T19:08:34.534Z

Authors: K. Behrndt

Published: 1995-06-16T14:31:55.000Z

## Abstract

This model also known as chiral null model is a generalization of the gravitational wave and fundamental string background and is exact in the $\\a'$ expansion. The reduction to 4 dimensions yields a stationary IWP solution which couples to 7 gauge fields (one gravi-photon and 6 matter gauge fields) and 4 scalars. Special cases are the Taub-NUT geometry and rotating black holes. These solutions possess a T-self-dual point where the black hole becomes massless. Discussing the S-duality we show that the Taub-NUT geometry allows an S-self-dual point and that the electric black hole corresponds to a magnetic black hole or an H-monopole. We could identify the massless black hole as $N\_L=0$ and confirm the H-monopole as an $N\_L=1$ string states.

## Recorded benchmark results

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## Original sources and implementation

[Original paper](<https://arxiv.org/abs/hep-th/9506106>)

[PDF](<https://arxiv.org/pdf/hep-th/9506106.pdf>)