72 research outputs found
Holography in the Large J Limit of AdS/CFT Correspondence and Its Applications
We give a brief expository discussion on the holographic correspondence of
correlation functions in the large J limit of AdS/CFT conjecture. We first
review our proposals on the interpretation of the so-called GKPW relation in
the large J limit or BMN limit, which are based upon a tunneling picture in
relating the AdS bulk to its boundary. Some concrete results, explicitly
confirming our picture, are summarized. We then proceed to comment on various
issues related to this subject, such as extension of the present picture to
nonconformal Dp-brane backgrounds, the correlators of deformed Wilson loops,
spinning-string/spin-chain correspondence, and the inclusion of higher
string-loop effects. In particular, as for the deformation of Wilson loops, we
present a typical tunneling world-sheet solution which can be used for direct
derivation of the expectation values of deformed Wilson loops following our
picture.Comment: 21 pages, written version of a talk given at the symposium "Frontiers
of Quantum Science", YITP, Kyoto, Feb. 2005, corrected typos and some minor
revisions of tex
World-Sheet String Duality and the Hidden Supersymmetry
It is reviewed how space-time supersymmetry is realized nonlinearly in open
superstring theory without making the GSO projection. We show that the
world-sheet string dualities, viz. dualities of open-closed strings and of
open-open strings, play crucial roles for the existence of 10 dimensional N=2
supersymmetry in a spontaneously broken phase. We also speculate on a possible
mechanism of the restoration of supersymmetry from the viewpoint of world-sheet
dynamics.Comment: 12 pages, talk presented at the 10th International Symposium on
String Theory (July 3-7, Fukuoka, Japan, 2001) and a part of lectures given
at the Summer Conference on Strings (July 16-27, Beijing, China, 2001
Field Theory of Yang-Mills Quantum Mechanics for D Particles
We propose a new field-theoretic framework for formulating the
non-relativistic quantum mechanics of D particles in a Fock space of U(N)
Yang-Mills theories with all different N in a unified way. D-particle field
operators, creating and annihilating a D particle and hence changing N one by
one, are defined. The base space of these D-particle fields is a (complex)
vector space of infinite dimensions. The gauge invariance of Yang-Mills quantum
mechanics is reinterpreted as a quantum-statistical symmetry, which is taken
into account by setting up a novel algebraic and projective structure in the
formalism. Ordinary physical observables of Yang-Mills theory, obeying the
standard algebra, are expressed as bilinear forms of the D-particle fields.
Together with the open-closed string duality, our new formulation suggests a
trinity of three different but mutually dual viewpoints in string theory.Comment: corrected typos, corrected references, 39 pages, 2 figures, version
to be published in Prog. Theor. Phy
Supergravity, AdS/CFT Correspondence and Matrix Models
The recent developments towards the possible non-perturbative formulation of
string/M theory using supersymmetric Yang-Mills matrix models (SYMs) are
discussed. In the first part, we give a critical review on the status of our
present understanding, focusing on the connection of the D0-brane matrix models
to supergravity and its relevance to the so-called Matrix-theory conjecture. We
also discuss some problems concerning the conjectured relation between
supergravity in AdS background and SYM from the viewpoint of D-brane
interactions. We present a qualitative argument showing how the boundary
condition at AdS boundary dictates the correlators on the large N system of
source D-branes. Then, in the final part, we turn to the question how to
formulate the condensation of graviton in matrix models, taking the simplest
example of type IIB matrix model. We argue the emergence of a hidden symmetry
GL(10, R), beyond the manifest Lorentz symmetry SO(9,1), by embedding U(N)
model into models with higher N and by treating the whole recursive series of
models simultaneously. This suggests a possible approach toward background
independent formulations of matrix models.Comment: Expanded and combined version of two talks given at
Nishinomiya-Yukawa Symposium, Nov., 1998 and YITP workshop, Nov., 1998, 23
pages, no figures (revision: sentences and references are added to clarify
the relation between the space-time uncertainty relation and holography
String Theory : Where are we now?
This is a brief overview on the current status of string theory for
non-specialists. The purpose is to give an aspect on the nature of string
theory as a unified theory of all interactions including quantum gravity and to
discuss future perspectives. Particular emphases are put on the mysteries why
string theory contains gravity and why it resolves the ultraviolet problems.Comment: 19 pages, 1 figure, written version of a general talk in the workshop
"Frontier of Theoretical Physics", Beijing, Nov, 1999, minor typos correcte
What is Holography in the Plane-Wave Limit of AdS/CFT Correspondence ?
The issue of holographic principle in the PP-wave limit of the AdS/CFT
correspondence is discussed, in the hope of clarifying some confusions in the
literature. We show that, in the plane-wave limit, the relation between the
partition function in the bulk and the gauge-invariant correlation functions on
the boundary should be interpreted on the basis of a tunneling picture in the
semi-classical approximation which is appropriate for the plane-wave limit.
This leads to a natural relation between Euclidean S-matrix in the bulk and the
short-distance operator-product expansion of the so-called BMN operators on the
boundary.Comment: 17 pages, 2 figures, an expanded written version of talk at the
Nishinomiya Yukawa Memorial Symposium, Nishinomiya, November, 200
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