11,497 research outputs found
New potentials for conformal mechanics
We find under some mild assumptions that the most general potential of
1-dimensional conformal systems with time independent couplings is expressed as
, where is a homogeneous function with respect to a homothetic
motion in configuration space and is determined from an equation with
source a homothetic potential. Such systems admit at most an SL(2,\bR)
conformal symmetry which, depending on the couplings, is embedded in Diff(R)SL(2,\bR)V=\alpha
x^2+\beta x^{-2}\alpha\betaSL(2,\bR)AdS_2 x S^3AdS_2 x S^3 x S^3AdS_2/CFT_1$.Comment: 15 pages, significant changes, references adde
Seeking the balance: Patching double and exceptional field theories
We investigate the patching of double and exceptional field theories. In
double field theory the patching conditions imposed on the spacetime after
solving the strong section condition imply that the 3-form field strength
is exact. A similar conclusion can be reached for the form field strengths of
exceptional field theories after some plausive assumptions are made on the
relation between the transition functions of the additional coordinates and the
patching data of the form field strengths. We illustrate the issues that arise,
and explore several alternative options which include the introduction of
C-folds and of the topological geometrisation condition.Comment: substantial changes, section with example added, to appear in jhep,
24 page
The Universality of M-branes
We review the evidence for the various dualities amongst the five D=10
superstring theories and for the existence of M-theory using the associated
effective supergravity theories. We also summarise the combinatorial technics
developed for constructing BPS solutions in D=11 supergravity theory and
conjecture that all the BPS solutions of D<11 supergravity theories can be
derived from the BPS solutions of D=11 supergravity that preserve 1/2 the
supersymmetry. To demonstrate this, we derive the dyonic p-brane solutions from
eleven dimensions.Comment: Many changes have been made in the text and some references have been
added. 8 pages, Latex, Talk at the Imperial College Workshop 5-10 Jul
Brane Surgery with Thom Classes
We propose a method to investigate the conservation of brane charges at the
intersection of two or more branes using the Thom classes of their normal
bundles. In particular we find a relation between the charge of the branes
involved in the configuration and the charge of the defects on the branes due
to the intersection. We also explore the applications of our method for various
brane intersections in type II strings and M-theory.Comment: 20 pages, Phyzz
On the determination of the trilinear boson couplings in e^-e^+ --> lepton anti-neutrino quark anti-quark at LEPII
We present the full tree-order calculation of the process
e^+e^-\to\ell\bar{\nu}_\ell\; q \bqp including the width effects in a way
which is consistent with gauge invariance and high energy unitarity and which
has a natural interpretation within standard perturbation theory. We also
include C- and P-preserving deviations from Standard Model trilinear vector
boson couplings. An analysis of the sensitivity of these channels on the
trilinear couplings, using well measured angular variables of the four fermion
final state, is also presented.Comment: uuencoded file, 23 pages, February 95, references adde
The Solutions of Affine and Conformal Affine Toda Field Theories
We give new formulations of the solutions of the field equations of the
affine Toda and conformal affine Toda theories on a cylinder and
two-dimensional Minkowski space-time. These solutions are parameterised in
terms of initial data and the resulting covariant phase spaces are
diffeomorphic to the Hamiltonian ones. We derive the fundamental Poisson
brackets of the parameters of the solutions and give the general static
solutions for the affine theory.Comment: 11pp, phyzz
T-duality and the Worldvolume Solitons of Five-Branes and KK-Monopoles
We show that the fluxes of the various six-dimensional "gauge" theories are
associated to below threshold bound states of D-branes with the NS-5-branes and
KK-monopoles which preserve half of bulk supersymmetry. We then present the
supergravity solutions that correspond to these bound states. In addition using
the worldvolume solitons of IIA and IIB NS-5-branes and KK-monopoles, we
investigate the sectors of the "gauge" theories that preserve one quarter of
bulk supersymmetry. This leads to a generalization a supergravity solution
which has the interpretation of two intersecting NS-5-branes at a 3-brane and
to the construction of some of the worldvolume solitons of IIA and M-theory
KK-monopoles. Furthermore, using the IIA/IIB T-duality of the bulk theories, we
give the T-duality transformations of the worldvolume solitons of NS-5-branes
and KK-monopoles. We find that the worldvolume 0-brane, self-dual string and
2-brane solitons of NS-5-branes appear in the same T-duality chain.Comment: 20 pages, phyzzx, minor change
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