pinecone/core-2020-05-10-deduplication huggingface dataset:
A New Extension of Ho\v{r}ava-Lifshitz Gravity and Curing Pathologies of
  the Scalar Graviton

We consider an extension of the Ho\v{r}ava-Lifshitz gravity with extra
conformal symmetry by introducing a scalar field with higher order curvature
terms. Relaxing the exact local Weyl symmetry, we construct an action with
three free parameters which breaks local anisotropic Weyl symmetry but still
preserves residual global Weyl symmetry. At low energies, it reduces to a
Lorentz-violating scalar-tensor gravity. With a constant scalar field
background and particular choices of the parameters, it reduces to the
Ho\v{r}ava-Lifshitz (HL) gravity, but any perturbation from these particular
configurations produces some non-trivial extensions of HL gravity. The
perturbation analysis of the new extended HL gravity in the Minkowski
background shows thatthe pathological behaviors of scalar graviton, i.e., ghost
or instability problem, and strong coupling problem do not emerge up to cubic
order as well as quadratic order.Comment: 14 pages, version to appear in JHE
ABJM Baryon Stability and Myers effect

We consider magnetically charged baryon vertex like configurations in AdS^4 X
CP^3 with a reduced number of quarks l. We show that these configurations are
solutions to the classical equations of motion and are stable beyond a critical
value of l. Given that the magnetic flux dissolves D0-brane charge it is
possible to give a microscopical description in terms of D0-branes expanding
into fuzzy CP^n spaces by Myers dielectric effect. Using this description we
are able to explore the region of finite 't Hooft coupling.Comment: 29 pages, Latex; minor changes; version to appear in JHE
Holographic two dimensional QCD and Chern-Simons term

We present a holographic realization of large Nc massless QCD in two
dimensions using a D2/D8 brane construction. The flavor axial anomaly is dual
to a three dimensional Chern-Simons term which turns out to be of leading
order, and it affects the meson spectrum and holographic renormalization in
crucial ways. The massless flavor bosons that exist in the spectrum are found
to decouple from the heavier mesons, in agreement with the general lore of
non-Abelian bosonization. We also show that an external dynamical photon
acquires a mass through the three dimensional Chern-Simons term as expected
from the Schwinger mechanism. Massless two dimensional QCD at large Nc exhibits
anti-vector-meson dominance due to the axial anomaly.Comment: 22 page
Ultraviolet filtering of lattice configurations and applications to
  Monte Carlo dynamics

We present a detailed study of a filtering method based upon Dirac
quasi-zero-modes in the adjoint representation. The procedure induces no
distortions on configurations which are solutions of the euclidean classical
equations of motion. On the other hand, it is very effective in reducing the
short-wavelength stochastic noise present in Monte Carlo generated
configurations. After testing the performance of the method in various
situations, we apply it successfully to study the effect of Monte Carlo
dynamics on topological structures like instantons.Comment: 39 pages, 15 figure
Magnetic Catalysis and Quantum Hall Ferromagnetism in Weakly Coupled
  Graphene

We study the realization in a model of graphene of the phenomenon whereby the
tendency of gauge-field mediated interactions to break chiral symmetry
spontaneously is greatly enhanced in an external magnetic field. We prove that,
in the weak coupling limit, and where the electron-electron interaction
satisfies certain mild conditions, the ground state of charge neutral graphene
in an external magnetic field is a quantum Hall ferromagnet which spontaneously
breaks the emergent U(4) symmetry to U(2)XU(2).
  We argue that, due to a residual CP symmetry, the quantum Hall ferromagnet
order parameter is given exactly by the leading order in perturbation theory.
On the other hand, the chiral condensate which is the order parameter for
chiral symmetry breaking generically obtains contributions at all orders. We
compute the leading correction to the chiral condensate. We argue that the
ensuing fermion spectrum resembles that of massive fermions with a vanishing
U(4)-valued chemical potential. We discuss the realization of parity and charge
conjugation symmetries and argue that, in the context of our model, the charge
neutral quantum Hall state in graphene is a bulk insulator, with vanishing
longitudinal conductivity due to a charge gap and Hall conductivity vanishing
due to a residual discrete particle-hole symmetry.Comment: 35 page
A Very Light Dilaton

We present a completely perturbative model that displays behavior similar to
that of walking technicolor. In one phase of the model RG-trajectories run
towards an IR-fixed point but approximate scale invariance is spontaneously
broken before reaching the fixed point. The trajectories then run away from it
and a light dilaton appears in the spectrum. The mass of the dilaton is
controlled by the "distance" of the theory to the critical surface, and can be
adjusted to be arbitrarily small without turning off the interactions. There is
a second phase with no spontaneous symmetry breaking and hence no dilaton, and
in which RG trajectories do terminate at the IR-fixed point.Comment: Typos corrected, discussions added, references update
The physics of a new gauge boson in a Stueckelberg extension of the
  two-Higgs-doublet model

String theory constructions using D-brane physics offer a framework where
ingredients like extra abelian factors in the gauge group, more than one Higgs
doublet and a generalized Green-Schwarz mechanism appear at the same time.
Motivated by works towards the direction of obtaining the Standard Model in
orientifold constructions, we study in the present work a Stueckelberg
extension of the two-Higgs-doublet model. The distinctive features of our model
are i) a sharp decay width for the heavy gauge boson, and ii) a charged Higgs
boson having two main decay channels at tree level with equal branching ratios.Comment: 17 pages, 9 figure
On the dynamical generation of the Maxwell term and scale invariance

Gauge theories with no Maxwell term are investigated in various setups. The
dynamical generation of the Maxwell term is correlated to the scale invariance
properties of the system. This is discussed mainly in the cases where the gauge
coupling carries dimensions. The term is generated when the theory contains a
scale explicitly, when it is asymptotically free and in particular also when
the scale invariance is spontaneously broken. The terms are not generated when
the scale invariance is maintained. Examples studied include the large $N$
limit of the $CP^{N-1}$ model in $(2+\epsilon)$ dimensions, a 3D gauged
$\phi^6$ vector model and its supersymmetric extension. In the latter case the
generation of the Maxwell term at a fixed point is explored. The phase
structure of the $d=3$ case is investigated in the presence of a Chern-Simons
term as well. In the supersymmetric $\phi^6$ model the emergence of the Maxwell
term is accompanied by the dynamical generation of the Chern-Simons term and
its multiplet and dynamical breaking of the parity symmetry. In some of the
phases long range forces emerge which may result in logarithmic confinement.
These include a dilaton exchange which plays a role also in the case when the
theory has no gauge symmetry. Gauged Lagrangian realizations of the 2D coset
models do not lead to emergent Maxwell terms. We discuss a case where the gauge
symmetry is anomalous.Comment: 38 pages, 4 figures; v2 slightly improved, typos fixed, references
  added, published versio
B to strange tensor meson transition in a model with one universal extra dimension

We analyze the semileptonic B -> K-2* (1430)l(+)l(-) transition in universal extra dimension model. In particular, we present the sensitivity of related observables such as branching ratio, polarization distribution and forward-backward asymmetry to the compactification factor (1/R) of extra dimension. The obtained results from extra dimension model show overall a considerable deviation from the standard model predictions for small values of the compactification factor. This can be considered as an indication for existence of extra dimensions
(De)Constructing a Natural and Flavorful Supersymmetric Standard Model

Using the framework of deconstruction, we construct simple, weakly-coupled
supersymmetric models that explain the Standard Model flavor hierarchy and
produce a flavorful soft spectrum compatible with precision limits. Electroweak
symmetry breaking is fully natural; the mu-term is dynamically generated with
no B mu-problem and the Higgs mass is easily raised above LEP limits without
reliance on large radiative corrections. These models possess the distinctive
spectrum of superpartners characteristic of "effective supersymmetry": the
third generation superpartners tend to be light, while the rest of the scalars
are heavy.Comment: 36 pages, 4 figures ; v2: references added, expanded discussion of
  FCNC
Two Simple W' Models for the Early LHC

W' gauge bosons are good candidates for early LHC discovery. We define two
reference models, one containing a W'_R and one containing a W'_L, which may
serve as ``simplified models'' for presenting experimental results of W'
searches at the LHC. We present the Tevatron bounds on each model and compute
the constraints from precision electroweak observables. We find that indirect
low-energy constraints on the W'_L are quite strong. However, for a W'_R
coupling to right-handed fermions there exists a sizeable region in parameter
space beyond the bounds from the Tevatron and low-energy precision measurements
where even 50 inverse picobarns of integrated LHC luminosity are sufficient to
discover the W'_R. The most promising final states are two leptons and two
jets, or one lepton recoiling against a ``neutrino jet''. A neutrino jet is a
collimated object consisting of a hard lepton and two jets arising from the
decay of a highly boosted massive neutrino.Comment: 20 pages, 8 figures. v2: references adde
Surface Operator, Bubbling Calabi-Yau and AGT Relation

Surface operators in N=2 four-dimensional gauge theories are interesting
half-BPS objects. These operators inherit the connection of gauge theory with
the Liouville conformal field theory, which was discovered by Alday, Gaiotto
and Tachikawa. Moreover it has been proposed that toric branes in the A-model
topological strings lead to surface operators via the geometric engineering. We
analyze the surface operators by making good use of topological string theory.
Starting from this point of view, we propose that the wave-function behavior of
the topological open string amplitudes geometrically engineers the surface
operator partition functions and the Gaiotto curves of corresponding gauge
theories. We then study a peculiar feature that the surface operator
corresponds to the insertion of the degenerate fields in the conformal field
theory side. We show that this aspect can be realized as the geometric
transition in topological string theory, and the insertion of a surface
operator leads to the bubbling of the toric Calabi-Yau geometry.Comment: 36 pages, 14 figures. v2: minor changes and typos correcte
Measurement of the tt ̄ production cross section and the top quark mass in the dilepton channel in pp collisions at √s =7 TeV

The t t-bar production cross section and top quark mass are measured in proton-proton collisions at sqrt(s) = 7 TeV in a data sample corresponding to an integrated luminosity of 36 inverse picobarns collected by the CMS experiment. The measurements are performed in events with two leptons (electrons or muons) in the final state. Results of the cross section measurement in events with and without b-quark identification are obtained and combined. The measured value is sigma(t t-bar)=168 +/- 18 (stat.) +/- 14 (syst.) +/- 7 (lumi.) pb, consistent with predictions from the standard model. The top quark mass m(top) is reconstructed with two different methods, a full kinematic analysis and a matrix weighting technique. The combination yields a measurement of m(top)=175.5 +/- 4.6 (stat.) +/- 4.6 (syst.) GeV/c^2
The holographic fluid dual to vacuum Einstein gravity

We present an algorithm for systematically reconstructing a solution of the
(d+2)-dimensional vacuum Einstein equations from a (d+1)-dimensional fluid,
extending the non-relativistic hydrodynamic expansion of Bredberg et al in
arXiv:1101.2451 to arbitrary order. The fluid satisfies equations of motion
which are the incompressible Navier-Stokes equations, corrected by specific
higher derivative terms. The uniqueness and regularity of this solution is
established to all orders and explicit results are given for the bulk metric
and the stress tensor of the dual fluid through fifth order in the hydrodynamic
expansion. We establish the validity of a relativistic hydrodynamic description
for the dual fluid, which has the unusual property of having a vanishing
equilibrium energy density. The gravitational results are used to identify
transport coefficients of the dual fluid, which also obeys an interesting and
exact constraint on its stress tensor. We propose novel Lagrangian models which
realise key properties of the holographic fluid.Comment: 31 pages; v2: references added and minor improvements, published
  versio
Eulerian digraphs and toric Calabi-Yau varieties

We investigate the structure of a simple class of affine toric Calabi-Yau
varieties that are defined from quiver representations based on finite eulerian
directed graphs (digraphs). The vanishing first Chern class of these varieties
just follows from the characterisation of eulerian digraphs as being connected
with all vertices balanced. Some structure theory is used to show how any
eulerian digraph can be generated by iterating combinations of just a few
canonical graph-theoretic moves. We describe the effect of each of these moves
on the lattice polytopes which encode the toric Calabi-Yau varieties and
illustrate the construction in several examples. We comment on physical
applications of the construction in the context of moduli spaces for
superconformal gauged linear sigma models.Comment: 27 pages, 8 figure
Threshold Improved QCD Corrections for Stop-Antistop production at
  Hadron colliders

I present improved predictions for the total hadronic cross section of
stop-antistop production at hadron colliders including
next-to-next-to-leading-order threshold corrections and approximated Coulomb
corrections. The results are based on soft corrections, which are
logarithmically enhanced near threshold. I present analytic formulas for the
NNLO scaling functions at threshold and explicit numbers for the total hadronic
cross sections for the Tevatron and the LHC. Finally I discuss the systematic
error, the scale uncertainty and the PDF error of the hadronic cross section.Comment: 19 pages, 6 figure
Holographic de Sitter Universe

We propose to embed de Sitter space into five dimensional anti-de Sitter
space to compute some physical quantities of interest, using the AdS/CFT
correspondence. The static de Sitter can be considered as the conformal
structure of the boundary of the hyperbolic AdS5 with a horizon, thus energy as
well as entropy can be computed. The global dS can be embedded into a
half-global AdS5, and the dS entropy can be regarded as entanglement entropy in
this case. Finally, the inflationary dS can also be regarded as the boundary of
AdS5, and this can be extended to include general cosmology with a positive
cosmological constant, however at the price of introducing a naked null
singularity in the bulk unless the cosmology is pure de Sitter space.Comment: 12 pages, minor modifications and more references adde
Generalized matrix models and AGT correspondence at all genera

We study generalized matrix models corresponding to n-point Virasoro
conformal blocks on Riemann surfaces with arbitrary genus g. Upon AGT
correspondence, these describe four dimensional N=2 SU(2)^{n+3g-3} gauge
theories with generalized quiver diagrams. We obtain the generalized matrix
models from the perturbative evaluation of the Liouville correlation functions
and verify the consistency of the description with respect to degenerations of
the Riemann surface. Moreover, we derive the Seiberg-Witten curve for the N=2
gauge theory as the spectral curve of the generalized matrix model, thus
providing a check of AGT correspondence at all genera.Comment: 19 pages; v2: version to appear in JHE
Towards multi-scale dynamics on the baryonic branch of
  Klebanov-Strassler

We construct explicitly a new class of backgrounds in type-IIB supergravity
which generalize the baryonic branch of Klebanov-Strassler. We apply a
solution-generating technique that, starting from a large class of solutions of
the wrapped-D5 system, yields the new solutions, and then proceed to study in
detail their properties, both in the IR and in the UV. We propose a simple
intuitive field theory interpretation of the rotation procedure and of the
meaning of our new solutions within the Papadopoulos-Tseytlin ansatz, in
particular in relation to the duality cascade in the Klebanov-Strassler
solution. The presence in the field theory of different VEVs for operators of
dimensions 2, 3 and 6 suggests that this is an important step towards the
construction of the string dual of a genuinely multi-scale (strongly coupled)
dynamical model.Comment: 37 pages, 7 figures. References added, version to appear in JHE
Pulsating Strings in Lunin-Maldacena Backgrounds

We consider pulsating strings in Lunin-Maldacena backgrounds, specifically in
deformed Minkowski spacetime and deformed AdS_5xS^5. We find the relation
between the energy and the oscillation number of the pulsating string when the
deformation is small. Since the oscillation number is an adiabatic invariant it
can be used to explore the regime of highly excited string states. We then
quantize the string and look for such a sector. For the deformed Minkowski
background we find a precise match with the classical results if the
oscillation number is quantized as an even number. For the deformed AdS_5xS^5
we find a contribution which depends on the deformation parameter.Comment: 16 pages, 2 figures, typos fixe
Notes on the scattering amplitude / Wilson loop duality

We consider the duality between the four-dimensional S-matrix of planar
maximally supersymmetric Yang-Mills theory and the expectation value of
polygonal shaped Wilson loops in the same theory. We extend the duality to
amplitudes with arbitrary helicity states by introducing a suitable
supersymmetric extension of the Wilson loop. We show that this object is
determined by a host of recursion relations, which are valid at tree level and
at loop level for a certain "loop integrand" defined within the Lagrangian
insertion procedure. These recursion relations reproduce the BCFW ones obeyed
by tree-level scattering amplitudes, as well as their extension to loop
integrands which appeared recently in the literature, establishing the duality
to all orders in perturbation theory. Finally, we propose that a certain set of
finite correlation functions can be used to compute all first derivatives of
the logarithm of MHV amplitudes.Comment: 25 pages + appendix, 5 figure
Wall-Crossing from Boltzmann Black Hole Halos

A key question in the study of N=2 supersymmetric string or field theories is
to understand the decay of BPS bound states across walls of marginal stability
in the space of parameters or vacua. By representing the potentially unstable
bound states as multi-centered black hole solutions in N=2 supergravity, we
provide two fully general and explicit formulae for the change in the (refined)
index across the wall. The first, "Higgs branch" formula relies on Reineke's
results for invariants of quivers without oriented loops, specialized to the
Abelian case. The second, "Coulomb branch" formula results from evaluating the
symplectic volume of the classical phase space of multi-centered solutions by
localization. We provide extensive evidence that these new formulae agree with
each other and with the mathematical results of Kontsevich and Soibelman (KS)
and Joyce and Song (JS). The main physical insight behind our results is that
the Bose-Fermi statistics of individual black holes participating in the bound
state can be traded for Maxwell-Boltzmann statistics, provided the (integer)
index \Omega(\gamma) of the internal degrees of freedom carried by each black
hole is replaced by an effective (rational) index \bar\Omega(\gamma)=
\sum_{m|\gamma} \Omega(\gamma/m)/m^2. A similar map also exists for the refined
index. This observation provides a physical rationale for the appearance of the
rational Donaldson-Thomas invariant \bar\Omega(\gamma) in the works of KS and
JS. The simplicity of the wall crossing formula for rational invariants allows
us to generalize the "semi-primitive wall-crossing formula" to arbitrary decays
of the type \gamma\to M\gamma_1+N\gamma_2 with M=2,3.Comment: 71 pages, 1 figure; v3: changed normalisation of symplectic form
  3.22, corrected 3.35, other cosmetic change
Goldstini Can Give the Higgs a Boost

Supersymmetric collider phenomenology depends crucially on whether the
lightest observable-sector supersymmetric particle (LOSP) decays, and if so,
what the LOSP decay products are. For instance, in SUSY models where the
gravitino is lighter than the LOSP, the LOSP decays to its superpartner and a
longitudinal gravitino via supercurrent couplings. In this paper, we show that
LOSP decays can be substantially modified when there are multiple sectors that
break supersymmetry, where in addition to the gravitino there are light uneaten
goldstini. As a particularly striking example, a bino-like LOSP can have a near
100% branching fraction to a higgs boson and an uneaten goldstino, even if the
LOSP has negligible higgsino fraction. This occurs because the uneaten
goldstino is unconstrained by the supercurrent, allowing additional operators
to mediate LOSP decay. These operators can be enhanced in the presence of an R
symmetry, leading to copious boosted higgs production in SUSY cascade decays.Comment: 30 pages, 12 figures; v2: title change, clarifications added, version
  to appear in JHE
Classical Effective Field Theory for Weak Ultra Relativistic Scattering

Inspired by the problem of Planckian scattering we describe a classical
effective field theory for weak ultra relativistic scattering in which field
propagation is instantaneous and transverse and the particles' equations of
motion localize to the instant of passing. An analogy with the non-relativistic
(post-Newtonian) approximation is stressed. The small parameter is identified
and power counting rules are established. The theory is applied to reproduce
the leading scattering angle for either a scalar interaction field or
electro-magnetic or gravitational; to compute some subleading corrections,
including the interaction duration; and to allow for non-zero masses. For the
gravitational case we present an appropriate decomposition of the gravitational
field onto the transverse plane together with its whole non-linear action. On
the way we touch upon the relation with the eikonal approximation, some
evidence for censorship of quantum gravity, and an algebraic ring structure on
2d Minkowski spacetime.Comment: 29 pages, 2 figures. v4: Duration of interaction is determined in Sec
  4 and detailed in App C. Version accepted for publication in JHE