115 research outputs found
Generating functionals of correlation functions of p-form currents in AdS/CFT correspondence
The generating functional of correlation functions of the currents
corresponding to general massless -form potential is calculated in
correspondence of Maldacena. For this we construct the boundary-to-bulk Green's
functions of -form potentials. The proportional constant of the
current-current correlation function, which is related to the central charge of
the operator product expansion, is shown to be c=(d-p\over 2\pi^{d/2}) (\Gamma
(d-p) \over \Gamma ({d\over 2}-p)). The result agrees with the known cases
such as or 2.Comment: 1 + 12 pages(LaTeX). Ward identity problem clearfied with enlarged
reference
Correlators of currents corresponding to the massive -form fields in AdS/CFT correspondence
By solving the equations of motion of massive -form potential in
Anti-de-Sitter space and using the correspondence of Maldacena, the
generating functional of two-point correlation functions of the currents is
obtained. When the mass parameter vanishes the result agrees with the known
massless case.Comment: 1+12 pages. Sequel to hep-th/9809132(the massless case with different
method
Time evolution of rolling tachyons for a brane-antibrane pair
A precise form of the time evolution of rolling tachyons corresponding to a
brane-antibrane pair is investigated by solving the Hamiltonian equations of
motion under the assumption that in a region far away from branes the tachyon
vacuum is almost already achieved, even at the beginning of the rolling.Comment: 10 pages, 2 figures. Addition of references in v2, inclusion of more
details in v
Non-hermitian quantum canonical variables and the generalized ladder operators
Quantum canonical transformations of the second kind and the non-Hermitian realizations of the basic canonical commutation relations are investigated with a special interest in the generalization of the conventional ladder operators. The opeator ordering problem is shown to be resolved when the non-Hermitian realizations for the canonical variables which can not be measured simultaneously with the energy are chosen for the canonical quantizations. Another merit of the non-Hermitian representations is that it naturally allows us to introduce the generalized ladder operators with which one can solve eigenvalue problems quite neatly
Scalar Field Theory in the AdS/CFT Correspondence Revisited
We consider the role of boundary conditions in the
correspondence for the scalar field theory. Also a careful analysis of some
limiting cases is presented. We study three possible types of boundary
conditions, Dirichlet, Neumann and mixed. We compute the two-point functions of
the conformal operators on the boundary for each type of boundary condition. We
show how particular choices of the mass require different treatments. In the
Dirichlet case we find that there is no double zero in the two-point function
of the operator with conformal dimension . The Neumann case leads
to new normalizations for the boundary two-point functions. In the massless
case we show that the conformal dimension of the boundary conformal operator is
precisely the unitarity bound for scalar operators. We find a one-parameter
family of boundary conditions in the mixed case. There are again new
normalizations for the boundary two-point functions. For a particular choice of
the mixed boundary condition and with the mass squared in the range
the boundary operator has conformal dimension comprised
in the interval . For mass squared
the same choice of mixed boundary condition leads to a boundary operator whose
conformal dimension is the unitarity bound.Comment: 22 pages, LaTeX, minor errors corrected, Conclusions and one
reference added, final version to be published in Nucl. Phys.
Spinor Exchange in AdS_{d+1}
We explicitly calculate a Witten diagram with general spinor field exchange
on -dimensional Euclidean Anti-de Sitter space, which is necessary to
evaluate four-point correlation functions with spinor fields when we make use
of the AdS/CFT correspondence, especially in supersymmetric cases. We also show
that the amplitude can be reduced to a scalar exchange amplitude. We discuss
the operator product expansion of the dual conformal field theory by
interpreting the short distance expansion of the amplitude according to the
AdS/CFT correspondence.Comment: 20 pages, harvmac; typos corrected and some English expressions
improved; final version to appear in Nucl. Phys.
Spinning deformations of the D1-D5 system and a geometric resolution of Closed Timelike Curves
The SO(4) isometry of the extreme Reissner-Nordstrom black hole of N=1, D=5
supergravity can be partly broken, without breaking any supersymmetry, in two
different ways. The ``right'' solution is a rotating black hole (BMPV); the
``left'' is interpreted as a black hole in a Godel universe. In ten dimensions,
both spacetimes are described by deformations of the D1-D5-pp-wave system with
the property that the non-trivial Closed Timelike Curves of the five
dimensional manifold are absent in the universal covering space of the ten
dimensional manifold. In the decoupling limit, the BMPV deformation is
normalizable. It corresponds to the vev of an IR relevant operator of dimension
\Delta=1. The Godel deformation is sub-leading in \alpha' unless we take an
infinite vorticity limit; in such case it is a non-normalizable perturbation.
It corresponds to the insertion of a vector operator of dimension \Delta=5.
Thus we conclude that from the dual (1+1)-CFT viewpoint the SO(4) R-symmetry is
broken `spontaneously' in the BMPV case and explicitly in the Godel case.Comment: 20 pages, no figures, LaTeX; v2: Minor improvements, to appear in
Nucl. Phys.
- …
