Pohlmeyer-reduced form of string theory in AdS_5 x S^5: semiclassical expansion

TL;DR

This paper explores the Pohlmeyer reduction of the AdS_5 x S^5 superstring, demonstrating that the reduced gauged WZW model with fermionic terms maintains a close classical and quantum relationship with the original superstring, supported by one-loop evidence.

Contribution

It introduces a new Pohlmeyer-reduced formulation of the superstring in AdS_5 x S^5, showing its quantum equivalence at one-loop level with the original theory.

Findings

The reduced model is a UV-finite gauged WZW theory with an integrable potential.

Classical and quantum relations between original and reduced theories are strongly supported.

One-loop calculations confirm the conjectured equivalence of partition functions.

Abstract

We consider the Pohlmeyer-reduced formulation of the AdS_5 x S^5 superstring. It is constructed by introducing new variables which are algebraically related to supercoset current components so that the Virasoro conditions are automatically solved. The reduced theory is a gauged WZW model supplemented with an integrable potential and fermionic terms that ensure its UV finiteness. The original superstring theory and its reduced counterpart are closely related at the classical level, and we conjecture that they remain related at the quantum level as well, in the sense that their quantum partition functions evaluated on respective classical solutions are equal. We provide evidence for the validity of this conjecture at the one-loop level, i.e. at the first non-trivial order of the semiclassical expansion near several classes of classical solutions.