pinecone/core-2020-05-10-deduplication huggingface dataset:
Reconstruction of Monte Carlo replicas from Hessian parton distributions

We explore connections between two common methods for quantifying the
uncertainty in parton distribution functions (PDFs), based on the Hessian error
matrix and Monte-Carlo sampling. CT14 parton distributions in the Hessian
representation are converted into Monte-Carlo replicas by a numerical method
that reproduces important properties of CT14 Hessian PDFs: the asymmetry of
CT14 uncertainties and positivity of individual parton distributions. The
ensembles of CT14 Monte-Carlo replicas constructed this way at NNLO and NLO are
suitable for various collider applications, such as cross section reweighting.
Master formulas for computation of asymmetric standard deviations in the
Monte-Carlo representation are derived. A correction is proposed to address a
bias in asymmetric uncertainties introduced by the Taylor series approximation.
A numerical program is made available for conversion of Hessian PDFs into
Monte-Carlo replicas according to normal, log-normal, and Watt-Thorne sampling
procedures.Comment: 21 pages, 10 figures; final JHEP version, extended Sec. 2 to discuss
  sampling of asymmetric PDF replica distributions with imposed positivity
  constraint
Generalized IIB supergravity from exceptional field theory

The background underlying the $\eta$-deformed $AdS_5\times S^5$ sigma-model
is known to satisfy a generalization of the IIB supergravity equations. Their
solutions are related by T-duality to solutions of type IIA supergravity with
non-isometric linear dilaton. We show how the generalized IIB supergravity
equations can be naturally obtained from exceptional field theory. Within this
manifestly duality covariant formulation of maximal supergravity, the
generalized IIB supergravity equations emerge upon imposing on the fields a
simple Scherk-Schwarz ansatz which respects the section constraint.Comment: 18 pages, version to appear in JHE
Refining the boundaries of the classical de Sitter landscape

We derive highly constraining no-go theorems for classical de Sitter
backgrounds of string theory, with parallel sources; this should impact the
embedding of cosmological models. We study ten-dimensional vacua of type II
supergravities with parallel and backreacted orientifold Op-planes and
Dp-branes, on four-dimensional de Sitter space-time times a compact manifold.
Vacua for p=3, 7 or 8 are completely excluded, and we obtain tight constraints
for p=4, 5, 6. This is achieved through the derivation of an enlightening
expression for the four-dimensional Ricci scalar. Further interesting
expressions and no-go theorems are obtained. The paper is self-contained so
technical aspects, including conventions, might be of more general interest.Comment: 15 pages + appendices and references; v2: few additions; v3:
  requirements on the sources and internal geometry clarified, version accepted
  for publication; v4: erratum added, minor impact on the result
Large $\nu$-$\bar{\nu}$ Oscillations from High-Dimensional Lepton Number
  Violating Operator

It is usually believed that the observation of the neutrino-antineutrino
(${\nu}$-$\bar{\nu}$) oscillations is almost impossible since the oscillation
probabilities are expected to be greatly suppressed by the square of tiny ratio
of neutrino masses to energies. Such an argument is applicable to most models
for neutrino mass generation based on the Weinberg operator, including the
seesaw models. However, in the present paper, we shall give a counterexample to
this argument, and show that large $\nu$-$\bar{\nu}$ oscillation probabilities
can be obtained in a class of models in which both neutrino masses and
neutrinoless double beta ($0\nu\beta\beta$) decays are induced by the
high-dimensional lepton number violating operator ${\cal O}_7 = \bar{u}_R l^c_R
\bar{L}_L H^*d_R + {\rm H.c.}$ with $u$ and $d$ representing the first two
generations of quarks. In particular, we find that the predicted
$0\nu\beta\beta$ decay rates have already placed interesting constraints on the
$\nu_e \leftrightarrow \bar{\nu}_e$ oscillation. Moreover, we provide an
UV-complete model to realize this scenario, in which a dark matter candidate
naturally appears due to the new $U(1)_d$ symmetry.Comment: 21 pages, 6 figure
The rigid Horowitz-Myers conjecture

The "new positive energy conjecture" Horowitz and Myers (1999) probes a
possible nonsupersymmetric AdS/CFT correspondence. We consider a version
formulated for complete, asymptotically Poincar\'e-Einstein Riemannian metrics
$(M,g)$ with bounded scalar curvature $R\ge -n(n-1)$. This version then asserts
that any such $(M,g)$ must have mass not less than the mass $m_0$ of a metric
$g_0$ induced on a time-symmetric slice of a certain AdS soliton spacetime. The
conjecture remains unproved, having so far resisted standard techniques. Little
is known other than that the conjecture is true for metrics which are
sufficiently small perturbations of $g_0$. We pose another test for the
conjecture. We assume its validity and attempt to prove as a corollary the
corresponding scalar curvature rigidity statement, that $g_0$ is the unique
asymptotically Poincar\'e-Einstein metric with mass $m=m_0$ obeying $R\ge
-n(n-1)$. Were a second such metric $g_1$ not isometric to $g_0$ to exist, it
then may well admit perturbations of lower mass, contradicting the assumed
validity of the conjecture. We find that the minimum mass metric must be static
Einstein, so the problem is reduced to that of static uniqueness. When $n=3$
the manifold is isometric to a time-symmetric slice of an AdS soliton
spacetime, unless it has a non-compact horizon. En route we study the mass
aspect, obtaining and generalizing known results. The mass aspect is (i)
related to the holographic energy density, (ii) a weighted invariant under
boundary conformal transformations when the bulk dimension is odd, and (iii)
zero for negative Einstein manifolds with Einstein conformal boundary.Comment: Statement and proof of Lemma 3.1 corrected, other minor change
Combined threshold and transverse momentum resummation for inclusive
  observables

We present a combined resummation for the transverse momentum distribution of
a colorless final state in perturbative QCD, expressed as a function of
transverse momentum pt and the scaling variable x. Its expression satisfies
three requirements: it reduces to standard transverse momentum resummation to
any desired logarithmic order in the limit pt-> 0 for fixed x, up to power
suppressed corrections in pt; it reduces to threshold resummation to any
desired logarithmic order in the limit x-> 1 for fixed pt, up to power
suppressed correction in 1-x; upon integration over transverse momentum it
reproduces the resummation of the total cross cross at any given logarithmic
order in the threshold x->1 limit. Its main ingredient, and our main new
result, is a modified form of transverse momentum resummation, which leads to
threshold resummation upon integration over pt, and for which we provide a
simple closed-form analytic expression in Fourier-Mellin (b,N) space. We give
explicit coefficients up to NNLL order for the specific case of Higgs
production in gluon fusion in the effective field theory limit. Our result
allows for a systematic improvement of the transverse momentum distribution
through threshold resummation which holds for all pt, and elucidates the
relation between transverse momentum resummation and threshold resummation at
the inclusive level, specifically by providing within perturbative QCD a simple
derivation of the main consequence of the so-called collinear anomaly of SCET.Comment: TIF-UNIMI-2016-11. Final version, to be published in JHEP. Modified
  references to the collinear anomaly; typos corrected in eqs 2.16, 2.18, 2.25,
  3.
Holographic flows and thermodynamics of Polyakov loop impurities

We study holographic probes dual to heavy quark impurities interpolating
between fundamental and symmetric/antisymmetric tensor representations in
strongly coupled N=4 supersymmetric gauge theory. These correspond to
non-conformal D3- and D5-brane probe embeddings in AdS_5 x S^5 exhibiting flows
on their world-volumes. By examining the asymptotic regimes of the embeddings
and the one-point function of static fields sourced by the boundary impurity,
we conclude that the D5-brane embedding describes the screening of fundamental
quarks in the UV into an antisymmetric source in the IR, whilst the
non-conformal, D3-brane solution interpolates between the symmetric
representation in the UV and fundamental sources in the IR. The D5-brane
embeddings exhibit nontrivial thermodynamics with multiple branches of
solutions, whilst the thermal analogue of the interpolating D3-brane solution
does not appear to exist.Comment: 28 pages, 7 figures, references added, version published in JHE
An Addendum to the Heisenberg-Euler effective action beyond one loop

We study the effective interactions of external electromagnetic fields
induced by fluctuations of virtual particles in the vacuum of quantum
electrodynamics. Our main focus is on these interactions at two-loop order. We
discuss in detail the emergence of the renowned Heisenberg-Euler effective
action from the underlying microscopic theory of quantum electrodynamics,
emphasizing its distinction from a standard one-particle irreducible effective
action. In our explicit calculations we limit ourselves to constant and slowly
varying external fields, allowing us to adopt a locally constant field
approximation. One of our main findings is that at two-loop order there is a
finite one-particle reducible contribution to the Heisenberg-Euler effective
action in constant fields, which was previously assumed to vanish. In addition
to their conceptual significance, our results are relevant for high-precision
probes of quantum vacuum nonlinearity in strong electromagnetic fields.Comment: 36 pages, 6 figures. Prefactor typo in Sect. IV D of arXiv versions
  and published JHEP version corrected. Corrections affect Eq. (57) [JHEP: Eq.
  (4.18)] and subsequent equation
Minimal $\cal N=4$ topologically massive supergravity

Using the superconformal framework, we construct a new off-shell model for
$\cal N=4$ topologically massive supergravity which is minimal in the sense
that it makes use of a single compensating vector multiplet and involves no
free parameter. As such, it provides a counterexample to the common lore that
two compensating multiplets are required within the conformal approach to
supergravity with eight supercharges in diverse dimensions. This theory is an
off-shell $\cal N=4$ supersymmetric extension of chiral gravity. All of its
solutions correspond to non-conformally flat superspaces. Its maximally
supersymmetric solutions include the so-called critical (4,0) anti-de Sitter
superspace introduced in arXiv:1205.4622, and well as warped critical (4,0)
anti-de Sitter superspaces. We also propose a dual formulation for the theory
in which the vector multiplet is replaced with an off-shell hypermultiplet.
Upon elimination of the auxiliary fields belonging to the hypermultiplet and
imposing certain gauge conditions, the dual action reduces to the one
introduced in arXiv:1605.00103.Comment: 38 pages, typos corrected and comments added, published versio
Tadpole-Induced Electroweak Symmetry Breaking and pNGB Higgs Models

We investigate induced electroweak symmetry breaking (EWSB) in models in
which the Higgs is a pseudo-Nambu-Goldstone boson (pNGB). In pNGB Higgs models,
Higgs properties and precision electroweak measurements imply a hierarchy
between the EWSB and global symmetry-breaking scales, $v_H \ll f_H$. When the
pNGB potential is generated radiatively, this hierarchy requires fine-tuning to
a degree of at least $\sim v_H^2/f_H^2$. We show that if Higgs EWSB is induced
by a tadpole arising from an auxiliary sector at scale $f_\Sigma \ll v_H$, this
tuning is significantly ameliorated or can even be removed. We present explicit
examples both in Twin Higgs models and in Composite Higgs models based on
$SO(5)/SO(4)$. For the Twin case, the result is a fully natural model with $f_H
\sim 1$ TeV and the lightest colored top partners at 2 TeV. These models also
have an appealing mechanism to generate the scales of the auxiliary sector and
Higgs EWSB directly from the scale $f_H$, with a natural hierarchy $f_\Sigma
\ll v_H \ll f_H \sim{\rm TeV}$. The framework predicts modified Higgs coupling
as well as new Higgs and vector states at LHC13.Comment: 21 pages, 5 figure
Partition functions of web diagrams with an O7$^-$-plane

We consider the computation of the topological string partition function for
5-brane web diagrams with an O7$^-$-plane. Since upon quantum resolution of the
orientifold plane these diagrams become non-toric web diagrams without the
orientifold we are able to apply the topological vertex to obtain the Nekrasov
partition function of the corresponding 5d theory. We apply this procedure to
the case of 5d $SU(N)$ theories with one hypermultiplet in the antisymmetric
representation and to the case of 5d pure $USp(2N)$ theories. For these cases
we discuss the dictionary between parameters and moduli of the 5d gauge theory
and lengths of 5-branes in the web diagram and moreover we perform comparison
of the results obtained via application of the topological vertex and the one
obtained via localisation techniques, finding in all instances we consider
perfect agreement.Comment: 51 pages, 23 figures. v2, minor clarifications in section
de Sitter Vacua of Strongly Interacting QFT

We use holographic correspondence to argue that Euclidean (Bunch-Davies)
vacuum is a late-time attractor of the dynamical evolution of quantum gauge
theories at strong coupling. The Bunch-Davies vacuum is not an adiabatic state,
if the gauge theory is non-conformal --- the comoving entropy production rate
is nonzero. Using the N=2* gauge theory holography, we explore prospects of
explaining current accelerated expansion of the Universe as due to the vacuum
energy of a strongly coupled QFT.Comment: 35 pages, 8 figures; v3: JHEP versio
Quasi parton distributions and the gradient flow

We propose a new approach to determining quasi parton distribution functions
(PDFs) from lattice quantum chromodynamics. By incorporating the gradient flow,
this method guarantees that the lattice quasi PDFs are finite in the continuum
limit and evades the thorny, and as yet unresolved, issue of the
renormalization of quasi PDFs on the lattice. In the limit that the flow time
is much smaller than the length scale set by the nucleon momentum, the moments
of the smeared quasi PDF are proportional to those of the light-front PDF. We
use this relation to derive evolution equations for the matching kernel that
relates the smeared quasi PDF and the light-front PDF. As part of this
discussion, we elucidate the relationship between the quasi and light-front
PDFs.Comment: 15 pages, no figures. Version published by JHE
Neutrino mixing and $R_K$ anomaly in $U(1)_X$ models: a bottom-up
  approach

We identify a class of $U(1)_X$ models which can explain the $R_K$ anomaly
and the neutrino mixing pattern, by using a bottom-up approach. The different
$X$-charges of lepton generations account for the lepton universality violation
required to explain $R_K$. In addition to the three right-handed neutrinos
needed for the Type-I seesaw mechanism, these minimal models only introduce an
additional doublet Higgs and a singlet scalar. While the former helps in
reproducing the quark mixing structure, the latter gives masses to neutrinos
and the new gauge boson $Z^\prime$. Our bottom-up approach determines the
$X$-charges of all particles using theoretical consistency and experimental
constraints. We find the parameter space allowed by the constraints from
neutral meson mixing, rare $b\to s$ decays and direct collider searches for
$Z^\prime$. Such a $Z^\prime$ may be observable at the ongoing run of the Large
Hadron Collider with a few hundred fb$^{-1}$ of integrated luminosity.Comment: 29 pages, 6 figures, minor typos corrected, one comment and
  references added, matches with the version published in JHE
Comments on Holographic Complexity

We study two recent conjectures for holographic complexity: the
complexity=action conjecture and the complexity=volume conjecture. In
particular, we examine the structure of the UV divergences appearing in these
quantities, and show that the coefficients can be written as local integrals of
geometric quantities in the boundary. We also consider extending these
conjectures to evaluate the complexity of the mixed state produced by reducing
the pure global state to a specific subregion of the boundary time slice. The
UV divergences in this subregion complexity have a similar geometric structure,
but there are also new divergences associated with the geometry of the surface
enclosing the boundary region of interest. We discuss possible implications
arising from the geometric nature of these UV divergences.Comment: Added paragraph in section 5 + minor correction
Noether charge, black hole volume, and complexity

In this paper, we study the physical significance of the thermodynamic
volumes of AdS black holes using the Noether charge formalism of Iyer and Wald.
After applying this formalism to study the extended thermodynamics of a few
examples, we discuss how the extended thermodynamics interacts with the recent
complexity = action proposal of Brown et al. (CA-duality). We, in particular,
discover that their proposal for the late time rate of change of complexity has
a nice decomposition in terms of thermodynamic quantities reminiscent of the
Smarr relation. This decomposition strongly suggests a geometric, and via
CA-duality holographic, interpretation for the thermodynamic volume of an AdS
black hole. We go on to discuss the role of thermodynamics in complexity =
action for a number of black hole solutions, and then point out the possibility
of an alternate proposal, which we dub "complexity = volume 2.0". In this
alternate proposal, the complexity would be thought of as the spacetime volume
of the Wheeler-DeWitt patch. Finally, we provide evidence that, in certain
cases, our proposal for complexity is consistent with the Lloyd bound whereas
CA-duality is not.Comment: v4: Changed to match published versio
Twisted finite-volume corrections to $K_{l3}$ decays with
  partially-quenched and rooted-staggered quarks

The determination of $|V_{us}|$ from kaon semileptonic decays requires the
value of the form factor $f_+(q^2=0)$ which can be calculated precisely on the
lattice. We provide the one-loop partially quenched chiral perturbation theory
expressions both with and without including the effects of staggered quarks for
all form factors at finite volume and with partially twisted boundary
conditions for both the vector current and scalar density matrix elements at
all $q^2$. We point out that at finite volume there are more form factors than
just $f_+$ and $f_-$ for the vector current matrix element but that the Ward
identity is fully satisfied. The size of the finite-volume corrections at
present lattice sizes is small. This will help improve the lattice
determination of $f_+(q^2=0)$ since the finite-volume error is the dominant
error source for some calculations. The size of the finite-volume corrections
may be estimated on a single lattice ensemble by comparing results for various
twist choices.Comment: 29 pages, 1 figur
On Longevity of I-ball/Oscillon

We study I-balls/oscillons, which are long-lived, quasi-periodic, and
spatially localized solutions in real scalar field theories. Contrary to the
case of Q-balls, there is no evident conserved charge that stabilizes the
localized configuration. Nevertheless, in many classical numerical simulations,
it has been shown that they are extremely long-lived. In this paper, we clarify
the reason for the longevity, and show how the exponential separation of time
scales emerges dynamically. Those solutions are time-periodic with a typical
frequency of a mass scale of a scalar field. This observation implies that they
can be understood by the effective theory after integrating out relativistic
modes. We find that the resulting effective theory has an approximate global
U(1) symmetry reflecting an approximate number conservation in the
non-relativistic regime. As a result, the profile of those solutions is
obtained via the bounce method, just like Q-balls, as long as the breaking of
the U(1) symmetry is small enough. We then discuss the decay processes of the
I-ball/oscillon by the breaking of the U(1) symmetry, namely the production of
relativistic modes via number violating processes. We show that the imaginary
part is exponentially suppressed, which explains the extraordinary longevity of
I-ball/oscillon. In addition, we find that there are some attractor behaviors
during the evolution of I-ball/oscillon that further enhance the lifetime. The
validity of our effective theory is confirmed by classical numerical
simulations. Our formalism may also be useful to study condensates of ultra
light bosonic dark matter, such as fuzzy dark matter, and axion stars, for
instance.Comment: 31 pages, 8 figures; v2: typos fixed, published version; v3: typos in
  the figures fixe
Refined open intersection numbers and the Kontsevich-Penner matrix model

A study of the intersection theory on the moduli space of Riemann surfaces
with boundary was recently initiated in a work of R. Pandharipande, J. P.
Solomon and the third author, where they introduced open intersection numbers
in genus 0. Their construction was later generalized to all genera by J. P.
Solomon and the third author. In this paper we consider a refinement of the
open intersection numbers by distinguishing contributions from surfaces with
different numbers of boundary components, and we calculate all these numbers.
We then construct a matrix model for the generating series of the refined open
intersection numbers and conjecture that it is equivalent to the
Kontsevich-Penner matrix model. An evidence for the conjecture is presented.
Another refinement of the open intersection numbers, which describes the
distribution of the boundary marked points on the boundary components, is also
discussed.Comment: 35 pages, 13 figures; references adde
BPS spectrum on AdS$_3\times $S$^3 \times $S$^3 \times $S$^1$

The BPS spectrum of string theory on AdS$_3\times {\rm S}^3 \times {\rm S}^3
\times {\rm S}^1$ is determined using a world-sheet description in terms of WZW
models. It is found that the theory only has BPS states with $j^+ = j^-$ where
$j^{\pm}$ refer to the spins of the $\mathfrak{su}(2)$ algebras of the large
${\cal N}=4$ superconformal algebra. We then re-examine the BPS spectrum of the
corresponding supergravity and find that, in contradistinction to previous
claims in the literature, also in supergravity only the states with $j^+=j^-$
are BPS. This resolves a number of long-standing puzzles regarding the BPS
spectrum of string theory and supergravity in this background.Comment: 36 pages; ancillary file included, v2: changed statement about
  spectrally flowed sectors, minor typos correcte
AC conductivity for a holographic Weyl Semimetal

We study the AC electrical conductivity at zero temperature in a holographic
model for a Weyl semimetal. At small frequencies we observe a linear dependence
in the frequency. The model shows a quantum phase transition between a
topological semimetal (Weyl semimetal phase) with a non vanishing anomalous
Hall conductivity and a trivial semimetal. The AC conductivity has an
intermediate scaling due to the presence of a quantum critical region in the
phase diagram of the system. The phase diagram is reconstructed using the
scaling properties of the conductivity. We compare with the experimental data
of [1502.03807] obtaining qualitative agreement.Comment: 27 pages, 5 figures and 3 appendices. Published version; references
  added, discussion of section 5 extended and typos correcte