pinecone/core-2020-05-10-deduplication huggingface dataset:
N = 2 supersymmetric sigma-models and duality

For two families of four-dimensional off-shell N = 2 supersymmetric nonlinear
sigma-models constructed originally in projective superspace, we develop their
formulation in terms of N = 1 chiral superfields. Specifically, these theories
are: (i) sigma-models on cotangent bundles T*M of arbitrary real analytic
Kaehler manifolds M; (ii) general superconformal sigma-models described by
weight-one polar supermultiplets. Using superspace techniques, we obtain a
universal expression for the holomorphic symplectic two-form \omega^{(2,0)}
which determines the second supersymmetry transformation and is associated with
the two complex structures of the hyperkaehler space T*M that are complimentary
to the one induced from M. This two-form is shown to coincide with the
canonical holomorphic symplectic structure. In the case (ii), we demonstrate
that \omega^{(2,0)} and the homothetic conformal Killing vector determine the
explicit form of the superconformal transformations. At the heart of our
construction is the duality (generalized Legendre transform) between off-shell
N = 2 supersymmetric nonlinear sigma-models and their on-shell N = 1 chiral
realizations. We finally present the most general N = 2 superconformal
nonlinear sigma-model formulated in terms of N = 1 chiral superfields. The
approach developed can naturally be generalized in order to describe 5D and 6D
superconformal nonlinear sigma-models in 4D N = 1 superspace.Comment: 31 pages, no figures; V2: reference and comments added, typos
  corrected; V3: more typos corrected, published versio
On Charged Lifshitz Black Holes

We obtain exact solutions of charged asymptotically Lifshitz black holes in
arbitrary (d+2) dimensions, generalizing the four dimensional solution
investigated in 0908.2611[hep-th]. We find that both the conventional
Hamiltonian approach and the recently proposed method for defining mass in
non-relativistic backgrounds do not work for this specific example. Thus the
mass of the black hole can only be determined by the first law of
thermodynamics. We also obtain perturbative solutions in five-dimensional
Gauss-Bonnet gravity. The ratio of shear viscosity over entropy density and the
DC conductivity are calculated in the presence of Gauss-Bonnet corrections.Comment: 24 pages, no figures, to appear in JHE
Conductivity and Diffusion Constant in Lifshitz Backgrounds

We study the DC conductivity and the diffusion constant for asymptotically
Lifshitz black branes in $(d+2)$- dimensions with arbitrary dynamical exponent
$z$. For a solvable example with $z=2, d=4$, we calculate the real-time
correlation functions, from which we can read off the corresponding
conductivity and diffusion constant. For black branes with arbitrary $z$ and
$d$, we work out the conductivity and obtain the diffusion constant by making
use of the Einstein relation. All the results agree with those obtained via the
membrane paradigm.Comment: 18 pages, no figures, references added, to appear in JHE
Central Exclusive Production in QCD

We investigate the theoretical description of the central exclusive
production process, h1+h2 -> h1+X+h2. Taking Higgs production as an example, we
sum logarithmically enhanced corrections appearing in the perturbation series
to all orders in the strong coupling. Our results agree with those originally
presented by Khoze, Martin and Ryskin except that the scale appearing in the
Sudakov factor, mu=0.62 \sqrt{\hat{s}}, should be replaced with
mu=\sqrt{\hat{s}}, where \sqrt{\hat{s}} is the invariant mass of the centrally
produced system. We confirm this result using a fixed-order calculation and
show that the replacement leads to approximately a factor 2 suppression in the
cross-section for central system masses in the range 100-500 GeV.Comment: 41 pages, 19 figures; minor typos fixed; version published in JHE
On Horava-Lifshitz "Black Holes"

The most general spherically symmetric solution with zero shift is found in
the non-projectable Horava-Lifshitz class of theories with general coupling
constants. It contains as special cases, spherically symmetric solutions found
by other authors earlier. It is found that the generic solution has
conventional (AdS, dS or flat) asymptotics with a universal 1/r tail. There are
several special cases where the asymptotics differ, including the detailed
balance choice of couplings. The conventional thermodynamics of this general
class of solutions is established by calculating the energy, temperature and
entropy. Although several of the solutions have conventional horizons, for
particles with ultra-luminal dispersion relations such solutions appear to be
horizonless.Comment: Latex 41 pages, 5 figure
The Nuts and Bolts of Einstein-Maxwell Solutions

We find new non-supersymmetric solutions of five-dimensional ungauged
supergravity coupled to two vector multiplets. The solutions are regular,
horizonless and have the same asymptotic charges as non-extremal charged black
holes. An essential ingredient in our construction is a four-dimensional
Euclidean base which is a solution to Einstein-Maxwell equations. We construct
stationary solutions based on the Euclidean dyonic Reissner-Nordstrom black
hole as well as a six-parameter family with a dyonic Kerr-Newman-NUT base.
These solutions can be viewed as compactifications of eleven-dimensional
supergravity on a six-torus and we discuss their brane interpretation.Comment: 29 pages, 3 figure
Heterotic Action in SUGRA-SYM Background

We consider the generalization of the heterotic action considered by Cherkis
and Schwarz where the chiral bosons are introduced in a manifestly covariant
way using an auxiliary field. In particular, we construct the kappa-symmetric
heterotic action in ten-dimensional supergravity background coupled to super
Yang-Mills theory and prove its kappa-symmetry. The usual Bianchi identity of
Type I supergravity with super Yang-Mills $dH_3= -\tr F\wedge F$ is crucially
used. For technical reason, the Yang-Mills field is restricted to be abelian.Comment: 12 pages, no figures, added comments in the acknowledgmen
Froggatt-Nielsen models from E8 in F-theory GUTs

This paper studies F-theory SU(5) GUT models where the three generations of
the standard model come from three different curves. All the matter is taken to
come from curves intersecting at a point of enhanced E8 gauge symmetry. Giving
a vev to some of the GUT singlets naturally implements a Froggatt-Nielsen
approach to flavour structure. A scan is performed over all possible models and
the results are filtered using phenomenological constraints. We find a unique
model that fits observations of quark and lepton masses and mixing well. This
model suffers from two drawbacks: R-parity must be imposed by hand and there is
a doublet-triplet splitting problem.Comment: 42 pages; v2:journal version; v3:corrected typo in neutrino masse
The Momentum Kernel of Gauge and Gravity Theories

We derive an explicit formula for factorizing an $n$-point closed string
amplitude into open string amplitudes. Our results are phrased in terms of a
momentum kernel which in the limit of infinite string tension reduces to the
corresponding field theory kernel. The same momentum kernel encodes the
monodromy relations which lead to the minimal basis of color-ordered amplitudes
in Yang-Mills theory. There are interesting consequences of the momentum kernel
pertaining to soft limits of amplitudes. We also comment on surprising links
between gravity and certain combinations of kinematic and color factors in
gauge theory.Comment: 19 pages, 1 figur
Multi-loop amplitudes in maximally supersymmetric pure spinor field
  theory

This paper provides a more detailed background to the results of
arXiv:1004.2692 concerning properties of multi-loop amplitudes in a pure spinor
formulation of field theories with maximal supersymmetry. This involves the
development of a first quantised field theory version of the non-minimal pure
spinor formalism originally designed for describing superstring amplitudes. In
addition to superspace world-line fields, the formalism involves a set of
world-line ghost fields that are required for implementing BRST invariance with
a composite b ghost. In particular, we show that BRST invariance requires the
presence of certain contact terms. For four-point amplitudes, these are
important beyond two loops. We also present an alternative proof of the
"no-triangle hypothesis" and the vanishing of amplitudes with fewer than four
external particles.Comment: 65 pages, 15 figure
Superpartner spectrum of minimal gaugino-gauge mediation

We evaluate the sparticle mass spectrum in the minimal four-dimensional
construction that interpolates between gaugino and ordinary gauge mediation at
the weak scale. We find that even in the hybrid case -- when the messenger
scale is comparable to the mass of the additional gauge particles -- both the
right-handed as well as the left-handed sleptons are lighter than the bino in
the low-scale mediation regime. This implies a chain of lepton production and,
consequently, striking signatures that may be probed at the LHC already in the
near future.Comment: 8 pages, 3 figures; V2: refs and a few comments added; V3 title
  change
Lepton Flavor Violation in Complex SUSY Seesaw Models with Nearly
  Tribimaximal Mixing

We survey the lepton flavor violation branching ratios Br(mu->e,gamma),
Br(tau->mu,gamma), and Br(tau->e,gamma) in mSUGRA for a broad class of lepton
mass matrix textures that give nearly tribimaximal lepton mixing. Small
neutrino masses are generated by the type-I seesaw mechanism with
non-degenerate right-handed neutrino masses. The textures exhibit a
hierarchical mass pattern and can be understood from flavor models giving rise
to large leptonic mixing. We study the branching ratios for the most general
CP-violating forms of the textures. It is demonstrated that the branching
ratios can be enhanced by 2-3 orders of magnitude as compared to the
CP-conserving case. The branching ratios exhibit, however, a strong dependence
on the choice of the phases in the Lagrangian which affects the significance of
flavor models. In particular, for general CP-phases, the lepton flavor
violating rates appear to be essentially uncorrelated with the possible high-
and low-energy lepton mixing parameters, such as the reactor angle.Comment: 22 pages, 17 figures. Version to be published in JHE
Testing the gaugino AMSB model at the Tevatron via slepton pair
  production

Gaugino AMSB models-- wherein scalar and trilinear soft SUSY breaking terms
are suppressed at the GUT scale while gaugino masses adopt the AMSB form--
yield a characteristic SUSY particle mass spectrum with light sleptons along
with a nearly degenerate wino-like lightest neutralino and quasi-stable
chargino. The left- sleptons and sneutrinos can be pair produced at
sufficiently high rates to yield observable signals at the Fermilab Tevatron.
We calculate the rate for isolated single and dilepton plus missing energy
signals, along with the presence of one or two highly ionizing chargino tracks.
We find that Tevatron experiments should be able to probe gravitino masses into
the ~55 TeV range for inoAMSB models, which corresponds to a reach in gluino
mass of over 1100 GeV.Comment: 14 pages including 6 .eps figure
New supersymmetric higher-derivative couplings: Full N=2 superspace does
  not count!

An extended class of N=2 locally supersymmetric invariants with
higher-derivative couplings based on full superspace integrals, is constructed.
These invariants may depend on unrestricted chiral supermultiplets, on vector
supermultiplets and on the Weyl supermultiplet. Supersymmetry is realized
off-shell. A non-renormalization theorem is proven according to which none of
these invariants can contribute to the entropy and electric charges of BPS
black holes. Some of these invariants may be relevant for topological string
deformations.Comment: 24 pages, v2: version published in JHEP, one reference added and
  typos corrected, v3: reference adde
A positive-weight next-to-leading order simulation of weak boson pair
  production

In this article we describe simulations of ZZ, WZ and WW production based on
the positive weight next-to-leading-order matching scheme, Powheg, in the
Herwig++ event generator. Building on earlier efforts within the Herwig++
framework, the simulation includes a full description of truncated showering
effects, required to correctly model soft, wide angle, emissions in
angular-ordered parton showers. We utilize simple relations among each of the
diboson cross sections, holding to order alpha_S, in constructing the
simulation. Spin correlation effects are also included in the decays of the
vector bosons at the tree order. A large part of this work is concerned with a
full and thorough validation of the simulations through comparisons with
alternative methods and calculations.Comment: 32 pages, 9 figures; v2 references added; v3 commented on singly
  resonant contributions and damping factor
Long-lived charged Higgs at LHC as a probe of scalar Dark Matter

We study inert charged Higgs boson $H^\pm$ production and decays at LHC
experiments in the context of constrained scalar dark matter model (CSDMM). In
the CSDMM the inert doublet and singlet scalar's mass spectrum is predicted
from the GUT scale initial conditions via RGE evolution. We compute the cross
sections of processes $pp\to H^+H^-,\, H^\pm S_i^0$ at the LHC and show that
for light $H^\pm$ the first one is dominated by top quark mediated 1-loop
diagram with Higgs boson in s-channel. In a significant fraction of the
parameter space $H^\pm$ are long-lived because their decays to predominantly
singlet scalar dark matter (DM) and next-to-lightest (NL) scalar, $H^\pm\to
S_{\text{DM, NL}} ff',$ are suppressed by the small singlet-doublet mixing
angle and by the moderate mass difference $ \Delta M=M_{H^+}-M_{\text{DM}} .$
The experimentally measurable displaced vertex in $H^\pm$ decays to leptons
and/or jets and missing energy allows one to discover the $H^+H^-$ signal over
the huge $W^+W^-$ background. We propose benchmark points for studies of this
scenario at the LHC. If, however, $H^\pm$ are short-lived, the subsequent
decays $S_{\text{NL}}\to S_{\text{DM}} f\bar f$ necessarily produce additional
displaced vertices that allow to reconstruct the full $H^\pm$ decay chain.Comment: 15 pages, 5 figure
Boundary finite size corrections for multiparticle states and planar
  AdS/CFT

We propose formulas for the L\"uscher type finite size energy correction of
multiparticle states on the interval and evaluate them for the simplest case in
the AdS/CFT setting. By this we determine the leading wrapping correction to
the anomalous dimension of the simplest determinant type operator, which
corresponds to a one particle state on the Y=0 brane.Comment: 21 pages, 22 eps figures, v2: references added, v3: typos, fermionic
  signs are corrected in section 4, explicit results simplified, conclusion is
  unchange
Axions in the Landscape and String Theory

While axions seem ubiquitous in critical string theories, whether they might
survive in any string theoretic description of nature is a difficult question.
With some mild assumptions, one can frame the issues in the case that there is
an approximate supersymmetry below the underlying string scale. The problem of
axions is then closely tied to the question of how moduli are fixed. We
consider, from this viewpoint, the possibility that supersymmetry is broken at
an intermediate scale, as in "gravity mediation," at a low scale, as in gauge
mediation, and at a very high scale, to model the possibility that there is no
low energy supersymmetry. Putative mechanisms for moduli fixing can then be
systematically classified, and at least for intermediate and high scale
breaking, light axions appear plausible. In the course of this work, we are
lead to consider aspects of moduli fixing and supersymmetry breaking, and we
revisit the possibility of very large extra dimensions.Comment: 18 pages; v2, updated and added reference
Hydrodynamics of R-charged D1-branes

We study the hydrodynamic properties of strongly coupled $SU(N)$ Yang-Mills
theory of the D1-brane at finite temperature and at a non-zero density of
R-charge in the framework of gauge/gravity duality. The gravity dual
description involves a charged black hole solution of an
Einstein-Maxwell-dilaton system in 3 dimensions which is obtained by a
consistent truncation of the spinning D1-brane in 10 dimensions. We evaluate
thermal and electrical conductivity as well as the bulk viscosity as a function
of the chemical potential conjugate to the R-charges of the D1-brane. We show
that the ratio of bulk viscosity to entropy density is independent of the
chemical potential and is equal to $1/4\pi$. The thermal conductivity and bulk
viscosity obey a relationship similar to the Wiedemann-Franz law. We show that
at the boundary of thermodynamic stability, the charge diffusion mode becomes
unstable and the transport coefficients exhibit critical behaviour. Our method
for evaluating the transport coefficients relies on expressing the second order
differential equations in terms of a first order equation which dictates the
radial evolution of the transport coefficient. The radial evolution equations
can be solved exactly for the transport coefficients of our interest. We
observe that transport coefficients of the D1-brane theory are related to that
of the M2-brane by an overall proportionality constant which sets the
dimensions.Comment: 57 pages, 12 figure
Worldsheet four-point functions in AdS(3)/CFT(2)

We calculate some extremal and non-extremal four-point functions on the
sphere of certain chiral primary operators for strings on AdS_3 x S^3 x T^4.
The computation is done for small values of the spacetime cross-ratio where
global SL(2) and SU(2) descendants may be neglected in the intermediate
channel. Ignoring also current algebra descendants, we find that in the
non-extremal case the integrated worldsheet correlators factorize into
spacetime three-point functions, which is non-trivial due to the integration
over the moduli space. We then restrict to the extremal case and compare our
results with the four-point correlators recently computed in the dual boundary
theory. We also discuss a particular non-extremal correlator involving two
chiral and two anti-chiral operators.Comment: 34 pages, subsection on crossing symmetry adde
Higgs inflation: consistency and generalisations

We analyse the self-consistency of inflation in the Standard Model, where the
Higgs field has a large non-minimal coupling to gravity. We determine the
domain of energies in which this model represents a valid effective field
theory as a function of the background Higgs field. This domain is bounded
above by the cutoff scale which is found to be higher than the relevant
dynamical scales throughout the whole history of the Universe, including the
inflationary epoch and reheating. We present a systematic scheme to take into
account quantum loop corrections to the inflationary calculations within the
framework of effective field theory. We discuss the additional assumptions that
must be satisfied by the ultra-violet completion of the theory to allow
connection between the parameters of the inflationary effective theory and
those describing the low-energy physics relevant for the collider experiments.
A class of generalisations of inflationary theories with similar properties is
constructed.Comment: 25 pages, 1 figur
Fermion bag approach to the sign problem in strongly coupled lattice QED
  with Wilson fermions

We explore the sign problem in strongly coupled lattice QED with one flavor
of Wilson fermions in four dimensions using the fermion bag formulation. We
construct rules to compute the weight of a fermion bag and show that even
though the fermions are confined into bosons, fermion bags with negative
weights do exist. By classifying fermion bags as either simple or complex, we
find numerical evidence that complex bags with positive and negative weights
come with almost equal probabilities and this leads to a severe sign problem.
On the other hand simple bags mostly have a positive weight. Since the complex
bags almost cancel each other, we suggest that eliminating them from the
partition function may be a good approximation. This modified partition
function suffers only from a mild sign problem. We also find a simpler model
which does not suffer from any sign problem and may still be a good
approximation at small and intermediate values of the hopping parameter. We
also prove that when the hopping parameter is strictly infinite all fermion
bags are non-negative.Comment: 17 pages, 4 figures, 5 table
On duality symmetries of supergravity invariants

The role of duality symmetries in the construction of counterterms for
maximal supergravity theories is discussed in a field-theoretic context from
different points of view. These are: dimensional reduction, the question of
whether appropriate superspace measures exist and information about non-linear
invariants that can be gleaned from linearised ones. The former allows us to
prove that F-term counterterms cannot be E7(7)-invariant in D=4, N=8
supergravity or E6(6)-invariant in D=5 maximal supergravity. This is confirmed
by the two other methods which can also be applied to D=4 theories with fewer
supersymmetries and allow us to prove that N=6 supergravity is finite at three
and four loops and that N=5 supergravity is three-loop finite.Comment: Clarification of arguments and their consistency with higher
  dimensional divergences added, e.g. we prove the 5D 4L non-renormalisation
  theorem. The 4L N=6 divergence is also ruled out. References adde
Insights and possible resolution to the information loss paradox via the
  tunneling picture

This paper investigates the information loss paradox in the WKB/tunneling
picture of Hawking radiation. In the tunneling picture one can obtain the
tunneling amplitude to all orders in $\hbar$. However all terms beyond the
lowest, semi-classical term involve unknown constants. Despite this we find
that one can still arrive at interesting restrictions on Hawking radiation to
all orders in $\hbar$: (i) Taking into account only quantum corrections the
spectrum remains thermal to all orders. Thus quantum corrections by themselves
will not resolve the information loss paradox. (ii) The first quantum
correction give a temperature for the radiation which goes to zero as the mass
of the black hole goes to zero. Including higher order corrections changes this
nice result of the first order corrections. (iii) Finally we show that by
taking both quantum corrections and back reaction into account it is possible
under specific conditions to solve the information paradox by having the black
hole evaporate completely with the information carried away by the correlations
of the outgoing radiation.Comment: 16 pages revtex, 4 figures. The formula for temperature is corrected.
  Main conclusion about the possible resolution to information loss paradox
  unchanged. Erratum to be published JHE
Multi-Photon Signals from Composite Models at LHC

We analyze the collider signals of composite scalars that emerge in certain
little Higgs models and models of vectorlike confinement. Similar to the decay
of the pion into photon pairs, these scalars mainly decay through
anomaly-induced interactions into electroweak gauge bosons, leading to a
distinct signal with three or more photons in the final state. We study the
standard model backgrounds for these signals, and find that the LHC can
discover these models over a large range of parameter space with 30 fb$^{-1}$
at 14 TeV. An early discovery at the current 7 TeV run is possible in some
regions of parameter space. We also discuss possibilities to measure the spin
of the particles in the $\gamma \gamma $ and $Z\gamma $ decay channels.Comment: 18 pages, LaTe