Eur. Phys. J. C (2017) 77: 806
https://doi.org/10.1140/epjc/s10052-017-5379-3

Regular Article - Theoretical Physics

BCFT and OSFT moduli: an exact perturbative comparison

Dipartimento di Fisica, Universitá di Torino and INFN, Sezione di Torino, Via Pietro Giuria 1, 10125, Torino, Italy

^* e-mail: maccafer@to.infn.it

Received: 12 September 2017
Accepted: 8 November 2017
Published online: 26 November 2017

Abstract

Starting from the pseudo- gauge solution for marginal deformations in OSFT, we analytically compute the relation between the perturbative deformation parameter in the solution and the BCFT marginal parameter , up to fifth order, by evaluating the Ellwood invariants. We observe that the microscopic reason why and are different is that the OSFT propagator renormalizes contact-term divergences differently from the contour deformation used in BCFT.