Physics Department · Theoretical Division Università degli Studi di Milano · INFN Milano
Milano 1 String Theory Group

Seminars

Upcoming

30 Nov

Regular Strings Seminar

Bethe Ansatz equations, Calogero-Moser systems and elliptic functions

Mario De Marco, Université Libre de Bruxelles

Aula Teorici

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The superconformal indeces of 4d SCFTs count their BPS states and, holographically, give information on the microstates of the dual black holes. A possible approach to the exact computation of the index requires solving the so-called Bethe Ansatz equations (BAE). In this talk, I will introduce a rewriting of the BAE in terms of elliptic functions, focusing on the case with 16 supercharges. Such a rewriting permits 1) to quantitatively capture the conjectural relation of BAE with the Calogero-Moser integrable system (and the related continuous solutions) and 2) to rephrase the BAE in terms of configurations of lines on a plane intersecting an elliptic curve.

Past seminars

17 seminars in 2004

13 Dec

Supersymmetric Black Rings

Jan Gutowski, Mathematical Institute, University of Oxford

Room DC/1/26

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The recent discovery of supersymmetric black ring solutions has important implications for black hole uniqueness and other aspects of black hole physics in higher dimensions. The construction of these solutions is investigated, and a generalization of the single ring solution to a system of concentric (multi-charge) rings is presented. The entropy of some of these solutions is particularly interesting.

9 Dec

Effects of D-instantons in string amplitudes

Jorge Russo, ICREA, University of Barcelona

Sala Consiglio

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In type IIB superstring theory, D-instanton contributions to some physical quantities can be incorporated by generalizing tree-level results by a proper SL(2,Z) symmetrization. This approach has led to the determination of the exact non-perturbative form of certain terms in the type IIB effective action. We consider an SL(2,Z) symmetric version of the four-graviton amplitude and factorize the pure D-instanton contribution. We find some surprising effects in the different energy regimes. These results show that non-perturbative effects can lead to a high-energy behavior which is significantly different from the perturbative string behavior.

23 Nov

Lunch seminar

On higher spins (Ref.: hep-th/0405069, 0410090, 0210114)

Alberto Santambrogio, Physics Dept. - Theory Division - Universita' degli Studi di Milano - Bicocca

Room DC/1/26

11 Nov

Black Rings

Roberto Emparan, ICREA, University of Barcelona

Sala Consiglio

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I will give an overview of work done in the last few years on a novel class of black holes in five dimensions with ring-shaped horizons. In particular, I will discuss their implications for black hole uniqueness, as well as their role within string theory.

26 Oct

Teorie di gauge e istantoni in background di stringa

Alberto Lerda, Universita' del Piemonte Orientale

Sala Consiglio

12 Oct

Lunch seminar

Giant Gravitons in AdS/CFT (Discussion on articles hep-th/0406096 and hep-th/0409174)

Marco Caldarelli, Physics Dept. - Theory Division - Universita' degli Studi di Milano

Room DC/1/26

7 Oct

Lunch seminar

Non-supersymmetric strings vacua and quantum corrections to the classical moduli space

Matteo Cardella, Physics Dept. - Theory Division - Universita' degli Studi di Milano

Room DC/1/26

22 Sep

Lunch seminar

Discussion on Lin, Lunin, Maldacena's article (hep-th/0409174)

Room DC/1/26

15 Jul

One flavor QCD from supersymmetric gluodynamics via planar equivalence

Mikhail Shifman, Theoretical Physics Insitute - Minnesota University

Sala Consiglio

23 Jun

Fakeness of fake supergravity

Alessio Celi, Leuven University

Room DC/1/26

1 Jun

Lunch seminar

Cosmological solutions of gauged maximal supergravities in three dimensions

Dario Melis, Physics Dept. - Theory Division - Universita' degli Studi di Milano

Room DC/1/26

1 Apr

Recent Developmentes concerning Closed Timelike Curves in String Theory

Carlos Herdeiro, Physics Dept. - University of Porto

Room DC/1/26

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Closed Timelike Curves are present in a number of solutions of Classical General Relativity and are, in general, regarded as pathological. It was suggested by Hawking in the early 90s that the `Chronology Protection Mechanism' should involve quantum effects. It becomes therefore interesting to explore the nature of CTC's in a framework of quantum gravity like string theory. The recent discovery of supersymmetric Godel type universes in string theory which are T-dual to pp-waves and the existence of supersymmetric rotating black holes (which have Closed Timelike Curves) possessing a CFT description motivated several suggestions on how string theory might cope with Closed Timelike Curves. In this seminar I will review some of these recent suggestions.

9 Mar

Holographic interpretation of closed timelike curves

Dietmar Klemm, Physics Dept. - Theory Division - Universita' degli Studi di Milano

Room DC/1/26

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We give a pedagogical review of Goedel-type universes in string theory and of questions related to the appearance of closed timelike curves.

2 Mar

Lunch seminar

Giant gravitons and CFT dual descriptions

Pedro J. Silva, Physics Dept. - Theory Division - Universita' degli Studi di Milano

Room DC/1/26

19 Feb

Lunch seminar

Supersymmetry breaking from string orbifolds

Matteo Cardella, Physics Dept. - Theory Division - Universita' degli Studi di Milano

Room DC/1/26

10 Feb

Lunch seminar

On integrable systems

Giovanni Ortenzi, Mathematics Dept. - Universita' degli Studi di Milano - Bicocca

Room DC/1/26

3 Feb

Lunch seminar

OPE and central charges in 4D SCFT

Matteo Boni, Physics Dept. - Theory Division - Universita' degli Studi di Milano

Room DC/1/26