1,623 research outputs found
Higher Derivative Corrections to O-plane Actions: NS-NS Sector
We classify all possible two- and four-derivative couplings of bulk NS-NS
sector fields to a single Op-plane which are compatible with diffeomorphism
invariance and B-field gauge invariance. This is applicable to type IIA or IIB
superstrings or to the bosonic string. We then consider this general action in
various classes of backgrounds that admit a U(1) isometry and determine the
constraints on the couplings from consistency with T-duality. We show that this
consistency requires the two-derivative action to vanish, and the entire
non-linear four-derivative action is fixed up to one overall constant which can
be determined by comparison with a two-point scattering amplitude. The
resulting action is consistent with all previously computed couplings.Comment: 54 page
Public Health Versus Court-Sponsored Secrecy
Public health practice relies on access to information. Givelber and Robbins discuss the debate about court-sponsored secrecy: Whether or not courts should tolerate, edorse, or protect secrecy when the sequestered information might help protect the public health
Scalar-Vector Bootstrap
We work out all of the details required for implementation of the conformal
bootstrap program applied to the four-point function of two scalars and two
vectors in an abstract conformal field theory in arbitrary dimension. This
includes a review of which tensor structures make appearances, a construction
of the projectors onto the required mixed symmetry representations, and a
computation of the conformal blocks for all possible operators which can be
exchanged. These blocks are presented as differential operators acting upon the
previously known scalar conformal blocks. Finally, we set up the bootstrap
equations which implement crossing symmetry. Special attention is given to the
case of conserved vectors, where several simplifications occur.Comment: 76 pages, v3 moved several details into appendices, expanded
discussion of mixed symmetry projecto
String Corrected Spacetimes and SU(N)-Structure Manifolds
Using an effective field theory approach and the language of
SU(N)-structures, we study higher derivative corrections to the supersymmetry
constraints for compactifications of string or M-theory to Minkowski space. Our
analysis is done entirely in the target space and is thus very general, and
does not rely on theory-dependent details such as the amount of worldsheet
supersymmetry. For manifolds of real dimension n<4 we show that the internal
geometry remains flat and uncorrected. For n=4, 6, Kahler manifolds with
SU(N)-holonomy can become corrected to SU(N)-structure, while preserving
supersymmetry, once corrections are included.Comment: 27 page
Kaluza-Klein Theories Without Truncation
In this note we present a closed expression for the space-time effective
action for all bosonic fields (massless and massive) obtained from the
compactification of gravity or supergravity theories (such as type II or
eleven-dimensional supergravities) from to space-time dimensions.Comment: 20 page
Higher Derivative Corrections and Central Charges from Wrapped M5-branes
We compute four-derivative corrections to the AdS supergravity actions
arising from the near-horizon geometry of N M5-branes wrapped on either one or
two Riemann surfaces. This setup features the novel presence of both gauged
isometries as well as nontrivial hypermultiplets. We argue that the 5d
Chern-Simons terms receive not only higher-derivative corrections but also
contributions from Killing vector parameters, which we find must also be
corrected. We check the central charges found by our supergravity methods
against the dual field theory results and find perfect agreement at leading and
subleading order in N. Along the way, we find higher derivative corrections to
general AdS_5 and AdS_3x\Sigma_g geometries.Comment: 32 pages + 16 pages appendice
Three-Point Disc Amplitudes in the RNS Formalism
We calculate all tree level string theory vacuum to Dp-brane disc amplitudes
involving an arbitrary RR-state and two NS-NS vertex operators. This
computation was earlier performed by K. Becker, Guo, and Robbins for the
simplest case of a RR-state of type C_{p-3}. Here we use the aid of a computer
to calculate all possible three-point amplitudes involving a RR-vertex operator
of type C_{p+1+2k}.Comment: 40 page
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