Eur. Phys. J. C (2015) 75: 490
https://doi.org/10.1140/epjc/s10052-015-3714-0

Regular Article - Theoretical Physics

Screening stringy horizons

¹ Université Libre de Bruxelles and International Solvay Institutes, ULB-Campus Plaine CPO231, 1050, Brussels, Belgium
² Departamento de Física, Universidad de Buenos Aires and IFIBA-CONICET Ciudad Universitaria, Pabellón 1, 1428, Buenos Aires, Argentina
³ Instituto de Física, Pontificia Universidad Católica de Valparaíso, Casilla 4059, Valparaiso, Chile
⁴ Centro de Estudios Científicos (CECs), Arturo Prat 514, Valdivia, Chile

^* e-mail: gaston@df.uba.ar

Received: 18 August 2015
Accepted: 1 October 2015
Published online: 14 October 2015

Abstract

It has been argued recently that string theory effects qualitatively modify the effective black hole geometry experienced by modes with radial momentum of order . At tree level, these effects can be explicitly worked out in two-dimensional string theory and have a natural explanation in the T-dual description as coming from the integration of the zero mode of the linear dilaton, which yields a contribution that affects the scattering phase shift in a peculiar manner. It has also been argued that the phase-shift modification has its origin in a region of the moduli space that does not belong to the exterior black hole geometry, leading to the conclusion that at high energy the physics of the problem is better described by the dual model. Here, we elaborate on this argument. We consider the contribution of world-sheet instantons in the two-dimensional Euclidean black hole -model and study its influence on the phase shift at high energy.