Gravitino condensation in fivebrane backgrounds

TL;DR

This paper calculates the tension of D3-branes in a fivebrane background using conformal field theory, revealing deviations from flat space that suggest gravitino and dilatino condensation as a gravitational instanton effect.

Contribution

It provides a novel calculation of D3-brane tension in a fivebrane background, linking deviations to gravitino/dilatino condensation phenomena.

Findings

D3-brane tension differs from flat space even as k -> infinity.

Finite curvature effects vanish in the flat limit, leaving topological effects.

Deviation indicates gravitino and/or dilatino condensation as a gravitational instanton.

Abstract

We calculate the tension of the D3-brane in the fivebrane background which is described by the exactly solvable SU(2)_k x U(1) world-sheet conformal field theory with large Kac-Moody level k. The D3-brane tension is extracted from the amplitude of one closed string exchange between two parallel D3-branes, and the amplitude is calculated by utilizing the open-closed string duality. The tension of the D3-brane in the background does not coincide with the one in the flat space-time even in the flat space-time limit: k -> infinity. The finite curvature effect should vanish in the flat space-time limit and only the topological effect can remain. Therefore, the deviation indicates the condensation of gravitino and/or dilatino which has been expected in the fivebrane background as a gravitational instanton.