1,027 research outputs found
Gauge Field Improvement,Form-Scalar Duality and Conformal Invariance
The problem of maintaining scale and conformal invariance in Maxwell and
general N-form gauge theories away from their critical dimension d=2(N+1) is
analyzed.We first exhibit the underlying group-theoretical clash between
locality,gauge,Lorentz and conformal invariance require- ments. "Improved"
traceless stress tensors are then constructed;each violates one of the above
criteria.However,when d=N+2,there is a duality equivalence between N-form
models and massless scalars.Here we show that conformal invariance is not
lost,by constructing a quasilocal gauge invariant improved stress tensor.The
correlators of the scalar theory are then reproduced,including the latter's
trace anomaly.Comment: 8 pages ,CERN-TH.7224 IAS 94/2
Numerical determination of entanglement entropy for a sphere
We apply Srednicki's regularization to extract the logarithmic term in the
entanglement entropy produced by tracing out a real, massless, scalar field
inside a three dimensional sphere in 3+1 flat spacetime. We find numerically
that the coefficient of the logarithm is -1/90 to 0.2 percent accuracy, in
agreement with an existing analytical result
Chern-Simons Gravity and Holographic Anomalies
We present a holographic treatment of Chern-Simons (CS) gravity theories in
odd dimensions. We construct the associated holographic stress tensor and
calculate the Weyl anomalies of the dual CFT.Comment: Added references, and minor corrections. 21 pages, havmac, no figure
Gauge Field Improvement, Form-Scalar Duality and Conformal Invariance and Quasi-locality
The problem of maintaining scale and conformal invariance in Maxwell and general N form gauge theories away from their critical dimension d_c = 2(N + 1) is analyzed. We first exhibit the underlying group-theoretical clash between locality, gauge, Lorentz and conformal invariance requirements. “Improved"-traceless-stress tensors are then constructed; each violates one of the above criteria. However, when d = N + 2, there is a duality equivalence between N-form models and massless scalars in d = N + 2. Here we show that N-form conformal invariance is not lost, by constructing a quasilocal gauge invariant improved stress tensor. The correlators of the scalar theory are then reproduced, including the latter’s trace anomaly. This resolves the old conformal invariance “paradox” between the dual partners
Navigation by satellite using two-way range and doppler data
Navigation by satellite using two-way range and Doppler dat
Free-field Representations and Geometry of some Gepner models
The geometry of Gepner model, where is investigated by
free-field representation known as "bc\bet\gm"-system. Using this
representation it is shown directly that internal sector of the model is given
by Landau-Ginzburg -orbifold. Then we consider
the deformation of the orbifold by marginal anti-chiral-chiral operator.
Analyzing the holomorphic sector of the deformed space of states we show that
it has chiral de Rham complex structure of some toric manifold, where toric
dates are given by certain fermionic screening currents. It allows to relate
the Gepner model deformed by the marginal operator to the -model on CY
manifold realized as double cover of with ramification along
certain submanifold.Comment: LaTex, 14 pages, some acknowledgments adde
Analyticity Properties of Graham-Witten Anomalies
Analytic properties of Graham-Witten anomalies are considered. Weyl anomalies
according to their analytic properties are of type A (coming from
-singularities in correlators of several energy-momentum tensors) or of
type B (originating in counterterms which depend logarithmically on a mass
scale). It is argued that all Graham-Witten anomalies can be divided into 2
groups: internal and external, and that all external anomalies are of type B,
whereas among internal anomalies there is one term of type A and all the rest
are of type B. This argument is checked explicitly for the case of a free
scalar field in a 6-dimensional space with a 2-dimensional submanifold.Comment: 2 typos correcte
Remarks on Resonant Scalars in the AdS/CFT Correspondence
The special properties of scalars having a mass such that the two possible
dimensions of the dual scalar respect the unitarity and the
Breitenlohner-Freedman bounds and their ratio is integral (``resonant
scalars'') are studied in the AdS/CFT correspondence. The role of logarithmic
branches in the gravity theory is related to the existence of a trace anomaly
and to a marginal deformation in the Conformal Field Theory. The existence of
asymptotic charges for the conformal group in the gravity theory is interpreted
in terms of the properties of the corresponding CFT.Comment: 16 pages, 1 figur
Universal Features of Holographic Anomalies
We study the mechanism by which gravitational actions reproduce the trace
anomalies of the holographically related conformal field theories. Two
universal features emerge: a) the ratios of type B trace anomalies in any even
dimension are independent of the gravitational action, being uniquely
determined by the underlying algebraic structure b) the normalization of the
type A and the overall normalization of the type B anomalies are given by
action dependent expressions with the dimension dependence completely fixed.Comment: 17 pages, harvma
General solutions of the Wess-Zumino consistency condition for the Weyl anomalies
The general solutions of the Wess-Zumino consistency condition for the
conformal (or Weyl, or trace) anomalies are derived. The solutions are
obtained, in arbitrary dimensions, by explicitly computing the cohomology of
the corresponding Becchi-Rouet-Stora-Tyutin differential in the space of
integrated local functions at ghost number unity. This provides a purely
algebraic, regularization-independent classification of the Weyl anomalies in
arbitrary dimensions. The so-called type-A anomaly is shown to satisfy a
non-trivial descent of equations, similarly to the non-Abelian chiral anomaly
in Yang-Mills theory.Comment: 9 pages. RevTeX fil
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