arXiv subjects

H. Verlinde

Publications and source records attributed to H. Verlinde.

12 recordsLinked to original sources

arXiv2000

A Matrix String Interpretation of the Large N Loop Equation

The existence two S-dual descriptions of (N,1) string bound states suggests that the strong coupling behaviour of electric flux lines in large N 2D SYM theory has a dual description in terms of weakly coupled IIB string theory. In support of this identification, we propose a dual interpretation of the SYM loop equation as a perturbative string Ward identity, expressing the conformal invariance of the corresponding boundary interaction. This correspondence can be viewed as a weak coupling check of the matrix string conjecture.

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arXiv2000

On Open/Closed String Duality

It was recently shown, using the AdS/CFT correspondence, that the low energy effective action of a large $N$ open string theory satisfies a holographic RG flow equation closely related to the Hamilton-Jacobi equation of 5-d supergravity. In this paper we re-obtain the same flow equation in the dual regime of small 't Hooft coupling $λ\ll 1$. Our derivation makes use of the conformal equivalence between planar open string diagrams and closed string tree diagrams. This equivalence can be viewed as a microscopic explanation of the open/closed string duality that underlies the AdS/CFT correspondence.

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arXiv1999

RG-Flow, Gravity and the Cosmological Constant

We study the low energy effective action $S$ of gravity, induced by integrating out gauge and matter fields, in a general class of Randall-Sundrum type string compactification scenarios with exponential warp factors. Our method combines dimensional reduction with the holographic map between between 5-d supergravity and 4-d large $N$ field theory. Using the classical supergravity approximation, we derive a flow equation of the effective action $S$ that controls its behavior under scale transformations. We find that as a result each extremum of $S$ automatically describes a complete RG trajectory of classical solutions. This implies that, provided the cosmological constant is canceled in the high energy theory, classical flat space backgrounds naturally remain stable under the RG-flow. The mechanism responsible for this stability is that the non-zero vacuum energy generated by possible phase transitions, is absorbed by a dynamical adjustment of the contraction rate of the warp factor.

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arXiv1999

On the Holographic Renormalization Group

We propose a direct correspondence between the classical evolution equations of 5-d supergravity and the renormalization group (RG) equations of the dual 4-d large $N$ gauge theory. Using standard Hamilton-Jacobi theory, we derive first order flow equations for the classical supergravity action $S$, that take the usual form of the Callan-Symanzik equations, including the corrections due to the conformal anomaly. This result gives direct support for the identification of $S$ with the quantum effective action of the gauge theory. In addition we find interesting new relations between the beta-functions and the counterterms that affect the 4-d cosmological and Newton constant.

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arXiv1997

Notes on Matrix and Micro Strings

We review some recent developments in the study of M-theory compactifications via Matrix theory. In particular we highlight the appearance of IIA strings and their interactions, and explain the unifying role of the M-theory five-brane for describing the spectrum of the T^5 compactification and its duality symmetries. The 5+1-dimensional micro-string theory that lives on the fivebrane world-volume takes a central place in this presentation.

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arXiv1997

5D Black Holes and Matrix Strings

We derive the world-volume theory, the (non)-extremal entropy and background geometry of black holes and black strings constructed out of the NS IIA fivebrane within the framework of matrix theory. The CFT description of strings propagating in the black hole geometry arises as an effective field theory.

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arXiv1997

Matrix String Theory

Via compactification on a circle, the matrix model of M-theory proposed by Banks et al suggests a concrete identification between the large N limit of two-dimensional N=8 supersymmetric Yang-Mills theory and type IIA string theory. In this paper we collect evidence that supports this identification. We explicitly identify the perturbative string states and their interactions, and describe the appearance of D-particle and D-membrane states.

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arXiv1996

Elliptic Genera of Symmetric Products and Second Quantized Strings

In this note we prove an identity that equates the elliptic genus partition function of a supersymmetric sigma model on the N-fold symmetric product $M^N/S_N$ of a manifold M to the partition function of a second quantized string theory on the space $M \times S^1$. The generating function of these elliptic genera is shown to be (almost) an automorphic form for O(3,2,Z). In the context of D-brane dynamics, this result gives a precise computation of the free energy of a gas of D-strings inside a higher-dimensional brane.

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arXiv1996

BPS Quantization of the Five-Brane

We give a unified description of all BPS states of M-theory compactified on $T^5$ in terms of the five-brane. We compute the mass spectrum and degeneracies and find that the $SO(5,5,Z)$ U-duality symmetry naturally arises as a T-duality by assuming that the world-volume theory of the five-brane itself is described by a string theory. We also consider the compactification on $S^1/Z_2 \times T^4$, and give a new explanation for its correspondence with heterotic string theory by exhibiting its dual equivalence to M-theory on $K3\times S^1$.

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arXiv1996

Counting Dyons in N=4 String Theory

We present a microscopic index formula for the degeneracy of dyons in four-dimensional N=4 string theory. This counting formula is manifestly symmetric under the duality group, and its asymptotic growth reproduces the macroscopic Bekenstein-Hawking entropy. We give a derivation of this result in terms of the type II five-brane compactified on K3, by assuming that its fluctuations are described by a closed string theory on its world-volume. We find that the degeneracies are given in terms of the denominator of a generalized super Kac-Moody algebra. We also discuss the correspondence of this result with the counting of D-brane states.

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arXiv1996

BPS Spectrum of the Five-Brane and Black Hole Entropy

We propose a formulation of 11-dimensional M-theory in terms of five-branes with closed strings on their world-volume. We use this description to construct the complete spectrum of BPS states in compactifications to six and five dimensions. We compute the degeneracy for fixed charge and find it to be in accordance with U-duality (which in our formulation is manifest in six dimensions) and the statistical entropy formula of the corresponding black hole. We also briefly comment on the four-dimensional case.

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arXiv1994

Black Hole Evaporation and Quantum Gravity

In this note we consider some consequences of quantum gravity on the process of black hole evaporation. In particular, we will explain the suggestion by 't Hooft that quantum gravitational interactions effectively exclude simultaneous measurements of the Hawking radiation and of the matter falling into the black hole. The complementarity of these measurements is supported by the fact that the commutators between the corresponding observables can be shown to grow uncontrollably large. The only assumption that is needed to obtain this result is that the creation and annihilation modes of the in-falling and out-going matter act in the same Hilbert space. We further illustrate this phenomenon in the context of two-dimensional dilaton gravity.

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