pinecone/core-2020-05-10-deduplication huggingface dataset:
Scaling laws near the conformal window of many-flavor QCD

We derive universal scaling laws for physical observables such as the
critical temperature, the chiral condensate, and the pion decay constant as a
function of the flavor number near the conformal window of many-flavor QCD in
the chiral limit. We argue on general grounds that the associated critical
exponents are all interrelated and can be determined from the critical exponent
of the running gauge coupling at the Caswell-Banks-Zaks infrared fixed point.
We illustrate our findings with the aid of nonperturbative functional
Renormalization Group (RG) calculations and low-energy QCD models.Comment: 18 pages, 4 figures, references added and discussion expanded
  (matches JHEP version
Aspects of the BMS/CFT correspondence

After a review of symmetries and classical solutions involved in the
AdS3/CFT2 correspondence, we apply a similar analysis to asymptotically flat
spacetimes at null infinity in 3 and 4 dimensions. In the spirit of two
dimensional conformal field theory, the symmetry algebra of asymptotically flat
spacetimes at null infinity in 4 dimensions is taken to be the semi-direct sum
of supertranslations with infinitesimal local conformal transformations and
not, as usually done, with the Lorentz algebra. As a first application, we
derive how the symmetry algebra is realized on solution space. In particular,
we work out the behavior of Bondi's news tensor, mass and angular momentum
aspects under local conformal transformations.Comment: 40 pages Latex fil
Composite Higgs Search at the LHC

The Higgs boson production cross-sections and decay rates depend, within the
Standard Model (SM), on a single unknown parameter, the Higgs mass. In
composite Higgs models where the Higgs boson emerges as a pseudo-Goldstone
boson from a strongly-interacting sector, additional parameters control the
Higgs properties which then deviate from the SM ones. These deviations modify
the LEP and Tevatron exclusion bounds and significantly affect the searches for
the Higgs boson at the LHC. In some cases, all the Higgs couplings are reduced,
which results in deterioration of the Higgs searches but the deviations of the
Higgs couplings can also allow for an enhancement of the gluon-fusion
production channel, leading to higher statistical significances. The search in
the H to gamma gamma channel can also be substantially improved due to an
enhancement of the branching fraction for the decay of the Higgs boson into a
pair of photons.Comment: 32 pages, 16 figure
Naturalness bounds in extensions of the MSSM without a light Higgs boson

Adopting a bottom-up point of view, we make a comparative study of the
simplest extensions of the MSSM with extra tree level contributions to the
lightest Higgs boson mass. We show to what extent a relatively heavy Higgs
boson, up to 200-350 GeV, can be compatible with data and naturalness. The
price to pay is that the theory undergoes some change of regime at a relatively
low scale. Bounds on these models come from electroweak precision tests and
naturalness, which often requires the scale at which the soft terms are
generated to be relatively low.Comment: 18 pages, 5 figures. v2: minor revision, added references. v3,v4:
  some numerical correction
Gaugino Anomaly Mediated SUSY Breaking: phenomenology and prospects for
  the LHC

We examine the supersymmetry phenomenology of a novel scenario of
supersymmetry (SUSY) breaking which we call Gaugino Anomaly Mediation, or
inoAMSB. This is suggested by recent work on the phenomenology of flux
compactified type IIB string theory. The essential features of this scenario
are that the gaugino masses are of the anomaly-mediated SUSY breaking (AMSB)
form, while scalar and trilinear soft SUSY breaking terms are highly
suppressed. Renormalization group effects yield an allowable sparticle mass
spectrum, while at the same time avoiding charged LSPs; the latter are common
in models with negligible soft scalar masses, such as no-scale or gaugino
mediation models. Since scalar and trilinear soft terms are highly suppressed,
the SUSY induced flavor and CP-violating processes are also suppressed. The
lightest SUSY particle is the neutral wino, while the heaviest is the gluino.
In this model, there should be a strong multi-jet +etmiss signal from squark
pair production at the LHC. We find a 100 fb^{-1} reach of LHC out to
m_{3/2}\sim 118 TeV, corresponding to a gluino mass of \sim 2.6 TeV. A double
mass edge from the opposite-sign/same flavor dilepton invariant mass
distribution should be visible at LHC; this, along with the presence of short--
but visible-- highly ionizing tracks from quasi-stable charginos, should
provide a smoking gun signature for inoAMSB.Comment: 30 pages including 14 .eps figure
Holographic metastability

We show how supersymmetric QCD in a slice of AdS can naturally acquire
metastable vacua. The formulation closely follows that of Intriligator, Seiberg
and Shih (ISS), with an "electric" sector on the UV brane and a "magnetic"
sector on the IR brane. However the 't Hooft anomaly matching that constrains
the Seiberg duality central to ISS is replaced by anomaly inflow and
cancellation, and the source of strong coupling is the CFT to which the theory
couples rather than the gauge groups. The theory contains an anomaly free
R-symmetry that, when broken by UV effects, leads to an O'Raifeartaigh model on
the IR brane. In contrast to ISS, the R-symmetry breaking in the UV can be
maximal, and yet the R-symmetry breaking in the IR theory remains under strict
control: there is no need for retrofitting of small parameters.Comment: 20 pages, 2 figure
Heterotic Models from Vector Bundles on Toric Calabi-Yau Manifolds

We systematically approach the construction of heterotic E_8 X E_8 Calabi-Yau
models, based on compact Calabi-Yau three-folds arising from toric geometry and
vector bundles on these manifolds. We focus on a simple class of 101 such
three-folds with smooth ambient spaces, on which we perform an exhaustive scan
and find all positive monad bundles with SU(N), N=3,4,5 structure groups,
subject to the heterotic anomaly cancellation constraint. We find that
anomaly-free positive monads exist on only 11 of these toric three-folds with a
total number of bundles of about 2000. Only 21 of these models, all of them on
three-folds realizable as hypersurfaces in products of projective spaces, allow
for three families of quarks and leptons. We also perform a preliminary scan
over the much larger class of semi-positive monads which leads to about 44000
bundles with 280 of them satisfying the three-family constraint. These 280
models provide a starting point for heterotic model building based on toric
three-folds.Comment: 41 pages, 5 figures. A table modified and a table adde
Direct determination of the solar neutrino fluxes from solar neutrino
  data

We determine the solar neutrino fluxes from a global analysis of the solar
and terrestrial neutrino data in the framework of three-neutrino mixing. Using
a Bayesian approach we reconstruct the posterior probability distribution
function for the eight normalization parameters of the solar neutrino fluxes
plus the relevant masses and mixing, with and without imposing the luminosity
constraint. This is done by means of a Markov Chain Monte Carlo employing the
Metropolis-Hastings algorithm. We also describe how these results can be
applied to test the predictions of the Standard Solar Models. Our results show
that, at present, both models with low and high metallicity can describe the
data with good statistical agreement.Comment: 24 pages, 1 table, 7 figures. Acknowledgments correcte
Baryon charge from embedding topology and a continuous meson spectrum in
  a new holographic gauge theory

We study a new holographic gauge theory based on probe D4-branes in the
background dual to D4-branes on a circle with antiperiodic boundary conditions
for fermions. Field theory configurations with baryons correspond to smooth
embeddings of the probe D4-branes with nontrivial winding around an S^4 in the
geometry. As a consequence, physics of baryons and nuclei can be studied
reliably in this model using the abelian Born-Infeld action. However,
surprisingly, we find that the meson spectrum is not discrete. This is related
to a curious result that the action governing small fluctuations of the gauge
field on the probe brane is the five-dimensional Maxwell action in Minkowski
space despite the non-trivial embedding of the probe brane in the curved
background geometry.Comment: 24 pages, LaTeX, 10 figures, v4: previously ignored effects of
  coupling to RR-fields included, meson spectrum qualitatively changed, v5:
  journal versio
HQET at order $1/m$: II. Spectroscopy in the quenched approximation

Using Heavy Quark Effective Theory with non-perturbatively determined
parameters in a quenched lattice calculation, we evaluate the splittings
between the ground state and the first two radially excited states of the $B_s$
system at static order. We also determine the splitting between first excited
and ground state, and between the $B_s^*$ and $B_s$ ground states to order
$1/m_b$. The Generalized Eigenvalue Problem and the use of all-to-all
propagators are important ingredients of our approach.Comment: (1+18) pages, 3 figures (4 pdf files); pdflatex; v2: corrections to
  table 1, results unaffecte
Fitting Parton Distribution Data with Multiplicative Normalization
  Uncertainties

We consider the generic problem of performing a global fit to many
independent data sets each with a different overall multiplicative
normalization uncertainty. We show that the methods in common use to treat
multiplicative uncertainties lead to systematic biases. We develop a method
which is unbiased, based on a self--consistent iterative procedure. We
demonstrate the use of this method by applying it to the determination of
parton distribution functions with the NNPDF methodology, which uses a Monte
Carlo method for uncertainty estimation.Comment: 33 pages, 5 figures: published versio
An instability of higher-dimensional rotating black holes

We present the first example of a linearized gravitational instability of an
asymptotically flat vacuum black hole. We study perturbations of a Myers-Perry
black hole with equal angular momenta in an odd number of dimensions. We find
no evidence of any instability in five or seven dimensions, but in nine
dimensions, for sufficiently rapid rotation, we find perturbations that grow
exponentially in time. The onset of instability is associated with the
appearance of time-independent perturbations which generically break all but
one of the rotational symmetries. This is interpreted as evidence for the
existence of a new 70-parameter family of black hole solutions with only a
single rotational symmetry. We also present results for the Gregory-Laflamme
instability of rotating black strings, demonstrating that rotation makes black
strings more unstable.Comment: 38 pages, 13 figure
Hidden Higgs Decaying to Lepton Jets

The Higgs and some of the Standard Model superpartners may have been
copiously produced at LEP and the Tevatron without being detected. We study a
novel scenario of this type in which the Higgs decays predominantly into a
light hidden sector either directly or through light SUSY states. Subsequent
cascades increase the multiplicity of hidden sector particles which, after
decaying back into the Standard Model, appear in the detector as clusters of
collimated leptons known as lepton jets. We identify the relevant collider
observables that characterize this scenario, and study a wide range of LEP and
Tevatron searches to recover the viable regions in the space of observables. We
find that the Higgs decaying to lepton jets can be hidden when the event
topology mimics that of hadronic backgrounds. Thus, as many as 10^4 leptonic
Higgs and SUSY decays may be hiding in the LEP and Tevatron data. We present
benchmark models with a 100 GeV Higgs that are consistent with all available
collider constraints. We end with a short discussion of strategies for
dedicated searches at LEP, the Tevatron and the LHC, that allow for a discovery
of the Higgs or SUSY particles decaying to lepton jets.Comment: 50 pages, 15 figures. v2: References added
On the geometry of C^3/D_27 and del Pezzo surfaces

We clarify some aspects of the geometry of a resolution of the orbifold X =
C3/D_27, the noncompact complex manifold underlying the brane quiver standard
model recently proposed by Verlinde and Wijnholt. We explicitly realize a map
between X and the total space of the canonical bundle over a degree 1 quasi del
Pezzo surface, thus defining a desingularization of X. Our analysis relys
essentially on the relationship existing between the normalizer group of D_27
and the Hessian group and on the study of the behaviour of the Hesse pencil of
plane cubic curves under the quotient.Comment: 23 pages, 5 figures, 2 tables. JHEP style. Added references.
  Corrected typos. Revised introduction, results unchanged
Superconformal Flavor Simplified

A simple explanation of the flavor hierarchies can arise if matter fields
interact with a conformal sector and different generations have different
anomalous dimensions under the CFT. However, in the original study by Nelson
and Strassler many supersymmetric models of this type were considered to be
'incalculable' because the R-charges were not sufficiently constrained by the
superpotential. We point out that nearly all such models are calculable with
the use of a-maximization. Utilizing this, we construct the simplest
vector-like flavor models and discuss their viability. A significant constraint
on these models comes from requiring that the visible gauge couplings remain
perturbative throughout the conformal window needed to generate the
hierarchies. However, we find that there is a small class of simple flavor
models that can evade this bound.Comment: 43 pages, 1 figure; V3: small corrections and clarifications,
  references adde
On effective actions of BPS branes and their higher derivative
  corrections

We calculate in detail the disk level S-matrix element of one Ramond-Ramond
field and three gauge field vertex operators in the world volume of BPS branes,
to find four gauge field couplings to all orders of $\alpha'$ up to on-shell
ambiguity. Then using these infinite couplings we find that the massless pole
of the field theory amplitude is exactly equal to the massless pole S-matrix
element of this amplitude for the $p=n$ case to all orders of $\alpha'$.
Finally we show that the infinite massless poles and the contact terms of this
amplitude for the $p=n+2$ case can be reproduced by the Born-Infeld action and
the Wess-Zumino actions and by their higher derivative corrections.Comment: 26 pages, 2 figures, minor corrections,references added and version
  published in JHE
Spiky Strings with Two Spins in AdS5

Using the reduction of the string sigma model to the 1-d Neumann integrable
model we reconstruct the closed string solution with two equal spins in AdS_5
which is specified by the number of round arcs and one winding number. From the
string sigma model itself as well as its reducion to the Neumann-Rosochatius
system we construct a spiky string solution with two unequal spins in AdS_5
whose ratio is fixed and derive its energy-spin relation. The string
configuration is characterized by the number of spikes and two equal winding
numbers associated with the two rotating angular directions
Holographic Metamagnetism, Quantum Criticality, and Crossover Behavior

Using high-precision numerical analysis, we show that 3+1 dimensional gauge
theories holographically dual to 4+1 dimensional Einstein-Maxwell-Chern-Simons
theory undergo a quantum phase transition in the presence of a finite charge
density and magnetic field. The quantum critical theory has dynamical scaling
exponent z=3, and is reached by tuning a relevant operator of scaling dimension
2. For magnetic field B above the critical value B_c, the system behaves as a
Fermi liquid. As the magnetic field approaches B_c from the high field side,
the specific heat coefficient diverges as 1/(B-B_c), and non-Fermi liquid
behavior sets in. For B<B_c the entropy density s becomes non-vanishing at zero
temperature, and scales according to s \sim \sqrt{B_c - B}. At B=B_c, and for
small non-zero temperature T, a new scaling law sets in for which s\sim
T^{1/3}. Throughout a small region surrounding the quantum critical point, the
ratio s/T^{1/3} is given by a universal scaling function which depends only on
the ratio (B-B_c)/T^{2/3}.
  The quantum phase transition involves non-analytic behavior of the specific
heat and magnetization but no change of symmetry. Above the critical field, our
numerical results are consistent with those predicted by the Hertz/Millis
theory applied to metamagnetic quantum phase transitions, which also describe
non-analytic changes in magnetization without change of symmetry. Such
transitions have been the subject of much experimental investigation recently,
especially in the compound Sr_3 Ru_2 O_7, and we comment on the connections.Comment: 23 pages, 8 figures v2: added ref
The Two-Loop Hexagon Wilson Loop in N = 4 SYM

In the planar N=4 supersymmetric Yang-Mills theory, the conformal symmetry
constrains multi-loop n-edged Wilson loops to be given in terms of the one-loop
n-edged Wilson loop, augmented, for n greater than 6, by a function of
conformally invariant cross ratios. That function is termed the remainder
function. In a recent paper, we have displayed the first analytic computation
of the two-loop six-edged Wilson loop, and thus of the corresponding remainder
function. Although the calculation was performed in the quasi-multi-Regge
kinematics of a pair along the ladder, the Regge exactness of the six-edged
Wilson loop in those kinematics entails that the result is the same as in
general kinematics. We show in detail how the most difficult of the integrals
is computed, which contribute to the six-edged Wilson loop. Finally, the
remainder function is given as a function of uniform transcendental weight four
in terms of Goncharov polylogarithms. We consider also some asymptotic values
of the remainder function, and the value when all the cross ratios are equal.Comment: 120 pages. References added and typos in Appendix G corrected
Measurement of J/psi photoproduction at large momentum transfer at HERA

The proton-dissociative diffractive photoproduction of J/psi mesons has been
studied in ep collisions with the ZEUS detector at HERA using an integrated
luminosity of 112 pb^-1. The cross section is presented as a function of the
photon-proton centre-of-mass energy and of the squared four-momentum transfer
at the proton vertex. The results are compared to perturbative QCD
calculations.Comment: 38 pages, 11 figures. In figures 6,9 and 11 added H1 measurement.
  Added comment on background contribution in subsection Evaluation of
  backgroun
Yukawa Textures From Heterotic Stability Walls

A holomorphic vector bundle on a Calabi-Yau threefold, X, with h^{1,1}(X)>1
can have regions of its Kahler cone where it is slope-stable, that is, where
the four-dimensional theory is N=1 supersymmetric, bounded by "walls of
stability". On these walls the bundle becomes poly-stable, decomposing into a
direct sum, and the low energy gauge group is enhanced by at least one
anomalous U(1) gauge factor. In this paper, we show that these additional
symmetries can strongly constrain the superpotential in the stable region,
leading to non-trivial textures of Yukawa interactions and restrictions on
allowed masses for vector-like pairs of matter multiplets. The Yukawa textures
exhibit a hierarchy; large couplings arise on the stability wall and some
suppressed interactions "grow back" off the wall, where the extended U(1)
symmetries are spontaneously broken. A number of explicit examples are
presented involving both one and two stability walls, with different
decompositions of the bundle structure group. A three family standard-like
model with no vector-like pairs is given as an example of a class of SU(4)
bundles that has a naturally heavy third quark/lepton family. Finally, we
present the complete set of Yukawa textures that can arise for any holomorphic
bundle with one stability wall where the structure group breaks into two
factors.Comment: 53 pages, 4 figures and 13 table
Rigidity of SU(2,2|2)-symmetric solutions in Type IIB

We investigate the existence of half-BPS solutions in Type IIB supergravity
which are invariant under the superalgebra SU(2,2|2) realized on either AdS_5 x
S^2 x S^1 or AdS_5 x S^3 warped over a Riemann surface \Sigma with boundary. We
prove that, in both cases, the only solution is AdS_5 x S^5 itself. We argue
that this result provides evidence for the non-existence of fully back-reacted
intersecting D3/D7 branes with either AdS_5 x S^2 x S^1 x \Sigma or AdS_5 x S^3
x \Sigma near-horizon limits.Comment: 55 page
Universal de Sitter solutions at tree-level

Type IIA string theory compactified on SU(3)-structure manifolds with
orientifolds allows for classical de Sitter solutions in four dimensions. In
this paper we investigate these solutions from a ten-dimensional point of view.
In particular, we demonstrate that there exists an attractive class of de
Sitter solutions, whose geometry, fluxes and source terms can be entirely
written in terms of the universal forms that are defined on all SU(3)-structure
manifolds. These are the forms J and Omega, defining the SU(3)-structure
itself, and the torsion classes. The existence of such universal de Sitter
solutions is governed by easy-to-verify conditions on the SU(3)-structure,
rendering the problem of finding dS solutions purely geometrical. We point out
that the known (unstable) solution coming from the compactification on SU(2)x
SU(2) is of this kind.Comment: 20 pages, 3 figures, v2: added reference
Applications of the Tunneling Method to Particle Decay and Radiation
  from Naked Singularities

Following recent literature on dS instability in presence of interactions, we
study the decay of massive particles in general FRW models and the emission
from naked singularities either associated with 4D charged black holes or with
2D shock waves, by means of the Hamilton--Jacobi tunneling method. It is shown
that the two-dimensional semi-classical tunneling amplitude from a naked
singularity computed in that way is the same as the one-loop result of quantum
field theory.Comment: LaTex document, 14 pages, two figure
Uniqueness Theorem for Black Hole Space-Times with Multiple Disconnected
  Horizons

We show uniqueness of stationary and asymptotically flat black hole
space-times with multiple disconnected horizons and with two rotational Killing
vector fields in the context of five-dimensional minimal supergravity
(Einstein-Maxwell-Chern-Simons gravity). The novelty in this work is the
introduction in the uniqueness theorem of intrinsic local charges measured near
each horizon as well as the measurement of local fluxes besides the asymptotic
charges that characterize a particular solution. A systematic method of
defining the boundary conditions on the fields that specify a black hole
space-time is given based on the study of its rod structure (domain structure).
Also, an analysis of known solutions with disconnected horizons is carried out
as an example of an application of this theorem.Comment: 28 pages, 5 figures. v3: Further improvements on uniqueness theorem,
  Lemma introduced for clarity of derivation, new quantities introduced to
  treat special case with zero flux, refs. added, typos fixe