pinecone/core-2020-05-10-deduplication huggingface dataset:
Yang-Baxter deformations of Minkowski spacetime

We study Yang-Baxter deformations of 4D Minkowski spacetime. The Yang-Baxter sigma model description was originally developed for principal chiral models based on a modified classical Yang-Baxter equation. It has been extended to coset curved spaces and models based on the usual classical Yang-Baxter equation. On the other hand, for flat space, there is the obvious problem that the standard bilinear form degenerates if we employ the familiar coset Poincaré group/Lorentz group. Instead we consider a slice of AdS5 by embedding the 4D Poincaré group into the 4D conformal group SO(2, 4) . With this procedure we obtain metrics and B-fields as Yang-Baxter deformations which correspond to well-known configurations such as T-duals of Melvin backgrounds, Hashimoto-Sethi and Spradlin-Takayanagi-Volovich backgrounds, the T-dual of Grant space, pp-waves, and T-duals of dS4 and AdS4. Finally we consider a deformation with a classical r-matrix of Drinfeld-Jimbo type and explicitly derive the associated metric and B-field which we conjecture to correspond to a new integrable system
NLO QCD + NLO EW corrections to $WZZ$ productions with leptonic decays
  at the LHC

Precision tests of the Standard Model (SM) require not only accurate
experiments, but also precise and reliable theoretical predictions. Triple
vector boson production provides a unique opportunity to investigate the
quartic gauge couplings and check the validity of the gauge principle in the
SM. Since the tree-level predictions alone are inadequate to meet this demand,
the next-to-leading order (NLO) calculation becomes compulsory. In this paper,
we calculate the NLO QCD + NLO electroweak (EW) corrections to the $W^{\pm}ZZ$
productions with subsequent leptonic decays at the $14~{\rm TeV}$ LHC by
adopting an improved narrow width approximation which takes into account the
off-shell contributions and spin correlations from the $W^{\pm}$- and $Z$-boson
leptonic decays. The NLO QCD+EW corrected integrated cross sections for the
$W^{\pm}ZZ$ productions and some kinematic distributions of final products are
provided. The results show that both the NLO QCD and NLO EW corrections are
significant. In the jet-veto event selection scheme with $p_{T,jet}^{cut} = 50~
{\rm GeV}$, the NLO QCD+EW relative corrections to the integrated cross section
are $20.5\%$ and $31.1\%$, while the genuine NLO EW relative corrections are
$-5.42\%$ and $-4.58\%$, for the $W^+ZZ$ and $W^-ZZ$ productions, respectively.
We also investigate the theoretical dependence of the integrated cross section
on the factorization/renormalization scale, and find that the scale uncertainty
is underestimated at the LO due to the fact that the strong coupling $\alpha_s$
is not involved in the LO matrix elements.Comment: 19 pages, 8 figure
Drell-Yan process with jet vetoes: breaking of generalized factorization

Resummation of hadron collision cross sections, when the measurement imposes
a hierarchy of scales, relies on factorization. Cancellation of Glauber /
Coulomb gluons is a necessary condition for factorization. For Drell-Yan-like
processes, the known proofs of cancellation of Glauber gluons are not
applicable when jet vetoes are introduced, via jet algorithms or event shape
variables such as the beam thrust. A priori, this does not rule out the
possibility that an unknown new cancellation mechanism exists, or the
possibility that a generalized factorization formalism is correct. To resolve
the questions, we construct a direct counter-example in QCD with scalar quarks,
contradicting any form of factorization in which the two collinear sectors are
decoupled from each other. In the counter-example, decoupling of the two
collinear sectors implies zero dependence of the beam thrust distribution on
the longitudinal spin of the incoming hadrons, but we find a non-zero spin
asymmetry at leading power due to Glauber gluons exchanged between spectators.
We discuss implications for resumming large logarithms from jet vetoes.Comment: 21 pages, 5 figure
The tetrahexahedric angular Calogero model

The spherical reduction of the rational Calogero model (of type A n−1 and after removing the center of mass) is considered as a maximally superintegrable quantum system, which describes a particle on the (n−2)-sphere subject to a very particular potential. We present a detailed analysis of the simplest non-separable case, n=4, whose potential is singular at the edges of a spherical tetrahexahedron. A complete set of independent conserved charges and of Hamiltonian intertwiners is constructed, and their algebra is elucidated. They arise from the ring of polynomials in Dunkl-deformed angular momenta, by classifying the subspaces invariant and antiinvariant under all Weyl reflections, respectively.Alexander von Humboldt Foundation/CHL 1153844 STPDFG/LE 838/12-
Positive Energy Conditions in 4D Conformal Field Theory

We argue that all consistent 4D quantum field theories obey a
spacetime-averaged weak energy inequality $\langle T^{00} \rangle \ge -C/L^4$,
where $L$ is the size of the smearing region, and $C$ is a positive constant
that depends on the theory. If this condition is violated, the theory has
states that are indistinguishable from states of negative total energy by any
local measurement, and we expect instabilities or other inconsistencies. We
apply this condition to 4D conformal field theories, and find that it places
constraints on the OPE coefficients of the theory. The constraints we find are
weaker than the "conformal collider" constraints of Hofman and Maldacena. We
speculate that there may be theories that violate the Hofman-Maldacena bounds,
but satisfy our bounds. In 3D CFTs, the only constraint we find is equivalent
to the positivity of 2-point function of the energy-momentum tensor, which
follows from unitarity. Our calculations are performed using momentum-space
Wightman functions, which are remarkably simple functions of momenta, and may
be of interest in their own right.Comment: 33 pages, 1 figure v2: adding clarifying information and fixed typo
Stratifying On-Shell Cluster Varieties: the Geometry of Non-Planar
  On-Shell Diagrams

The correspondence between on-shell diagrams in maximally supersymmetric
Yang-Mills theory and cluster varieties in the Grassmannian remains largely
unexplored beyond the planar limit. In this article, we describe a systematic
program to survey such 'on-shell varieties', and use this to provide a complete
classification in the case of $G(3,6)$. In particular, we find exactly 24
top-dimensional varieties and 10 co-dimension one varieties in $G(3,6)$---up to
parity and relabeling of the external legs. We use this case to illustrate some
of the novelties found for non-planar varieties relative to the case of
positroids, and describe some of the features that we expect to hold more
generally.Comment: 35 pages, 70 figures, and 1 table; also included is a file with
  explicit details for our classification. Signs corrected in two residue
  theorems, and a new interpretation (and formula) given for the las
The impact of non-minimally coupled gravity on vacuum stability

We consider vacuum decay in the presence of a non-minimal coupling to
gravity. We extend the usual thin-wall solution to include the non-minimal
coupling. We also perform a full numerical study and discuss the validity of
the new thin-wall approximation. Implications of a large cosmological constant,
whose influence on the geometry boosts the tunnelling rate, are discussed. Our
results show that the influence of the non-minimal coupling differs
significantly between the cases of Minkowski and deSitter backgrounds. In the
latter the decay probability quickly decreases when the coupling grows and in
fact the vacuum can be made absolutely stable simply due to introduction of the
non-minimal coupling. In the case of Minkowski background the effect is much
weaker and the decay rate even increases for small values of the non-minimal
coupling
CP violation in multibody decays of beauty baryons

Beauty baryons are being observed in large numbers in the LHCb detector. The
rich kinematic distributions of their multibody decays are therefore becoming
accessible and provide us with new opportunities to search for CP violation. We
analyse the angular distributions of some three- and four-body decays of
spin-$1/2$ baryons using the Jacob-Wick helicity formalism. The asymmetries
that provide access to small differences of CP-odd phases between decay
amplitudes of identical CP-even phases are notably discussed. The understanding
gained on processes featuring specific resonant intermediate states allows us
to establish which asymmetries are relevant for what purpose. It is for
instance shown that some CP-odd angular asymmetries measured by the LHCb
collaboration in the $\Lambda_b \to \Lambda\,\varphi \to p\,\pi\, K^+ K^-$
decay are expected to vanish identically.Comment: 2 figures, 16 tables, minor comments and references added in v2
  (published version
Probing New Physics Scales from Higgs and Electroweak Observables at
  $e^+ e^-$ Higgs Factory

New physics beyond the standard model (SM) can be model-independently
formulated via dimension-6 effective operators, whose coefficients (cutoffs)
characterize the scales of new physics. We study the probe of new physics
scales from the electroweak precision observables (EWPO) and the Higgs
observables (HO) at the future $e^+e^-$ Higgs factory (such as CEPC). To
optimize constraints of new physics from all available observables, we
establish a scheme-independent approach. With this formulation, we treat the SM
electroweak parameters and the coefficients of dimension-6 operators on equal
footing, which can be fitted simultaneously by the same $\chi^2$ function. As
deviations from the SM are generally small, we can expand the new physics
parameters up to linear order and perform an analytical $\chi^2$ fit to derive
the potential reach of the new physics scales. We find that the HO from both
Higgs produnction and decay rates can probe the new physics scales up to 10TeV
(and to 44TeV for the case of gluon-involved operator $\mathcal{O}_g$), and the
new physics scales of Yukawa-type operators can be probed by the precision
Higgs coupling measurements up to (13-25)TeV. Further including the EWPO can
push the limit up to 35TeV. From this prospect, we demonstrate that the EWPO
measured in the early phase of a Higgs factory can be as important as the Higgs
observables. These indirect probes of new physics scales at the Higgs factory
can mainly cover the energy range to be directly explored by the next
generation hadron colliders of pp(50-100TeV), such as the SPPC and FCC-hh.Comment: JHEP Final Version, 43 pages, 10 Tables, 6 Figs, using jheppub.sty
  format, only minor refinement
Nonlinear conductivity and the ringdown of currents in metallic
  holography

We study the electric and heat current response resulting from an electric
field quench in a holographic model of momentum relaxation at nonzero charge
density. After turning the electric field off, currents return to equilibrium
as governed by the vector quasi-normal modes of the dual black brane, whose
spectrum depends qualitatively on a parameter controlling the strength of
inhomogeneity. We explore the dynamical phase diagram as a function of this
parameter, showing that signatures of incoherent transport become identifiable
as an oscillatory ringdown of the heat current. We also study nonlinear
conductivity by holding the electric field constant. For small electric fields
a balance is reached between the driving electric field and the momentum sink
-- a steady state described by DC linear response. For large electric fields
Joule heating becomes important and the black branes exhibit significant time
dependence. In a regime where the rate of temperature increase is small, the
nonlinear electrical conductivity is well approximated by the DC linear
response calculation at an appropriate effective temperature.Comment: 28 pages, 10 figures. Plot of thermal conductivity added. Version as
  published in JHE
Quasi-Dirac neutrinos at the LHC

Lepton number violation is searched for at the LHC using same-sign leptons
plus jets. The standard lore is that the ratio of same-sign lepton to
opposite-sign lepton events, $R_{ll}$, is equal to $R_{ll}=1$ ($R_{ll}=0$) for
Majorana (Dirac) neutrinos. We argue that for "quasi-Dirac" neutrinos, $R_{ll}$
can have any value between 0 and 1, the precise value being controlled by the
mass splitting versus the width of the quasi-Dirac resonances. A measurement of
$R_{ll}\neq 0,1$ would then contain valuable information about the origin of
neutrino masses. We consider as an example the inverse seesaw mechanism in a
left-right symmetric scenario, which is phenomenologically particularly
interesting since all the heavy states in the high energy completion of the
model could be within experimental reach. A prediction of this scenario is a
correlation between the values of $R_{ll}$ and the ratio between the rates for
heavy neutrino decays into standard model gauge bosons, and into three body
final states $ljj$ mediated by off-shell $W_R$ exchange
Coupled-Channel $D\pi$, $D\eta$ and $D_{s}\bar{K}$ Scattering from
  Lattice QCD

We present the first lattice QCD study of coupled-channel $D\pi$, $D\eta$ and
$D_{s}\bar{K}$ scattering in isospin-1/2 in three partial waves. Using
distillation, we compute matrices of correlation functions with bases of
operators capable of resolving both meson and meson-meson contributions to the
spectrum. These correlation matrices are analysed using a variational approach
to extract the finite-volume energy eigenstates. Utilising L\"uscher's method
and its extensions, we constrain scattering amplitudes in $S$, $P$ and $D$-wave
as a function of energy. By analytically continuing the scattering amplitudes
to complex energies, we investigate the $S$-matrix singularities. Working at
$m_\pi \approx 391$ MeV, we find a pole corresponding to a $J^{P} = 0^{+}$
near-threshold bound state with a large coupling to $D\pi$. We also find a
deeply bound $J^{P} = 1^{-}$ state, and evidence for a $J^{P} = 2^{+}$ narrow
resonance coupled predominantly to $D\pi$. Elastic $D\pi$ scattering in the
isospin-$3/2$ channel is studied and we find a weakly repulsive interaction in
$S$-wave
Surface defects and instanton partition functions

We study the superconformal index of five-dimensional SCFTs and the sphere partition function of four-dimensional gauge theories with eight supercharges in the presence of co-dimension two half-BPS defects. We derive a prescription which is valid for defects which can be given a &quot;vortex construction&quot;, i.e. can be defined by RG flow from vortex configurations in a larger theory. We test the prescription against known results and expected dualities. We employ our prescription to develop a general computational strategy for defects defined by coupling the bulk degrees of freedom to a Gauged Linear Sigma Model living in co-dimension two.We study the superconformal index of five-dimensional SCFTs and the sphere partition function of four-dimensional gauge theories with eight supercharges in the presence of co-dimension two half-BPS defects. We derive a prescription which is valid for defects which can be given a &quot;vortex construction&quot;, i.e. can be defined by RG flow from vortex configurations in a larger theory. We test the prescription against known results and expected dualities. We employ our prescription to develop a general computational strategy for defects defined by coupling the bulk degrees of freedom to a Gauged Linear Sigma Model living in co-dimension two.11
Gluon and Wilson loop TMDs for hadrons of spin $\leq$ 1

In this paper we consider the parametrizations of gluon transverse momentum
dependent (TMD) correlators in terms of TMD parton distribution functions
(PDFs). These functions, referred to as TMDs, are defined as the Fourier
transforms of hadronic matrix elements of nonlocal combinations of gluon
fields. The nonlocality is bridged by gauge links, which have characteristic
paths (future or past pointing), giving rise to a process dependence that
breaks universality. For gluons, the specific correlator with one future and
one past pointing gauge link is, in the limit of small $x$, related to a
correlator of a single Wilson loop. We present the parametrization of Wilson
loop correlators in terms of Wilson loop TMDs and discuss the relation between
these functions and the small-$x$ `dipole' gluon TMDs. This analysis shows
which gluon TMDs are leading or suppressed in the small-$x$ limit. We discuss
hadronic targets that are unpolarized, vector polarized (relevant for
spin-$1/2$ and spin-$1$ hadrons), and tensor polarized (relevant for spin-$1$
hadrons). The latter are of interest for studies with a future Electron-Ion
Collider with polarized deuterons.Comment: 27 page
Bethe/Gauge correspondence in odd dimension: modular double,
  non-perturbative corrections and open topological strings

Bethe/Gauge correspondence as it is usually stated is ill-defined in five
dimensions and needs a "non-perturbative" completion; a related problem also
appears in three dimensions. It has been suggested that this problem, probably
due to incompleteness of Omega background regularization in odd dimension, may
be solved if we consider gauge theory on compact $S^5$ and $S^3$ geometries. We
will develop this idea further by giving a full Bethe/Gauge correspondence
dictionary on $S^5$ and $S^3$ focussing mainly on the eigenfunctions of (open
and closed) relativistic 2-particle Toda chain and its quantized spectral
curve: these are most properly written in terms of non-perturbatively completed
NS open topological strings. A key ingredient is Faddeev's modular double
structure which is naturally implemented by the $S^5$ and $S^3$ geometries.Comment: 53 pages, 7 tables, 7 figures; ver.2: references adde
Collider and Dark Matter Searches in the Inert Doublet Model from
  Peccei-Quinn Symmetry

Weakly Interacting Massive Particles (WIMPs) and axions are arguably the most
compelling dark matter candidates in the literature. Could they coexist as dark
matter particles? More importantly, can they be incorporated in a well
motivated framework in agreement with experimental data? In this work, we show
that this two component dark matter can be realized in the Inert Doublet Model
in an elegant and natural manner by virtue of the spontaneous breaking of a
Peccei-Quinn $U(1)_{PQ}$ symmetry into a residual $Z_2$ symmetry. The WIMP
stability is guaranteed by the $Z_{2}$ symmetry and a new dark matter
component, the axion, arises. There are two interesting outcomes: (i)
vector-like quarks needed to implement the Peccei-Quinn symmetry in the model
act as a portal between the dark sector and the SM fields with a
supersymmetry-type phenomenology at colliders; (ii) two-component Inert Doublet
Model re-opens the phenomenologically interesting 100-500 GeV mass region. We
show that the model can plausibly have two component dark matter and at the
same time avoid low and high energy physics constraints such as monojet and
dijet plus missing energy, as well as indirect and direct dark matter detection
bounds.Comment: 29pp, 6 Figure
Signal background interference effects in heavy scalar production and
  decay to a top-anti-top pair

We analyse the production of a top quark pair through a heavy scalar at the
LHC. We first review the main features of the signal as well as the
interference with the top-anti-top background at leading order in QCD. We then
study higher order QCD effects. While the background and the signal can be
obtained at NNLO and NLO in QCD respectively, that is not the case for their
interference, which is currently known only at LO. In order to improve the
accuracy of the prediction for the interference term, we consider the effects
of extra QCD radiation, i.e. the $2 \to 3$ (loop-induced) processes and obtain
an estimate of the NLO corrections. As a result, we find that the contribution
of the interference is important both at the total cross-section level and,
most importantly, for the line-shape of the heavy scalar. In particular for
resonances with widths larger than a couple of percent of the resonance mass,
the interference term distorts the invariant mass distribution and generically
leads to a non-trivial peak-dip structure. We study this process in a
simplified model involving an additional scalar or pseudoscalar resonance as
well as in the Two-Higgs-Doublet-Model for a set of representative benchmarks.
We present the constraints on simplified models featuring an extra scalar as
set by the LHC searches for top-anti-top resonances, and the implications of
the 750 GeV diphoton excess recently reported by CMS and ATLAS for the top pair
production assuming a scalar or a pseudoscalar resonance.Comment: 30 pages, 17 figure
Simplified Dark Matter Models with Charged Mediators: Prospects for
  Direct Detection

We consider direct detection prospects for a class of simplified models of
fermionic dark matter (DM) coupled to left and right-handed Standard Model
fermions via two charged scalar mediators with arbitrary mixing angle $\alpha$.
DM interactions with the nucleus are mediated by higher electromagnetic
moments, which, for Majorana DM, is the anapole moment. After giving a full
analytic calculation of the anapole moment, including its $\alpha$ dependence,
and matching with limits in the literature, we compute the DM-nucleon
scattering cross-section and show the LUX and future LZ constraints on the
parameter space of these models. We then compare these results with constraints
coming from $Fermi$-LAT continuum and line searches. Results in the
supersymmetric limit of these simplified models are provided in all cases. We
find that future direct detection experiments will be able to probe most of the
parameter space of these models for $\mathcal{O}(100-200)$ GeV DM and lightest
mediator mass $\lesssim \mathcal{O}(5\%)$ larger than the DM mass. The direct
detection prospects dwindle for larger DM mass and larger mass gap between the
DM and the lightest mediator mass, although appreciable regions are still
probed for $\mathcal{O}(200)$ GeV DM and lightest mediator mass $\lesssim
\mathcal{O}(20\%)$ larger than the DM mass. The direct detection bounds are
also attenuated near certain "blind spots" in the parameter space, where the
anapole moment is severely suppressed due to cancellation of different terms.
We carefully study these blind spots and the associated $Fermi$-LAT signals in
these regions.Comment: 30 pages, 10 captioned figures; v2: 32 pages, 10 captioned figures,
  revised and published versio
Nonlocal N=1 Supersymmetry

We construct $\mathcal{N}=1$ supersymmetric nonlocal theories in four
dimension. We discuss higher derivative extensions of chiral and vector
superfields, and write down generic forms of K\"ahler potential and
superpotential up to quadratic order. We derive the condition in which an
auxiliary field remains non-dynamical, and the dynamical scalars and fermions
are free from the ghost degrees of freedom. We also investigate the nonlocal
effects on the supersymmetry breaking and find that supertrace (mass) formula
is significantly modified even at the tree level.Comment: 12 pages, version published in JHE
Most general AdS_3 boundary conditions

We consider the most general asymptotically anti-de Sitter boundary
conditions in three-dimensional Einstein gravity with negative cosmological
constant. The metric contains in total twelve independent functions, six of
which are interpreted as chemical potentials (or non-normalizable fluctuations)
and the other half as canonical boundary charges (or normalizable
fluctuations). Their presence modifies the usual Fefferman-Graham expansion.
The asymptotic symmetry algebra consists of two sl(2)_k current algebras, the
levels of which are given by k=l/(4G_N), where l is the AdS radius and G_N the
three-dimensional Newton constant.Comment: 22 pp, v2: added refs. and subsection 4.4, v3: added two footnotes,
  v4: corrected minor misprint