pinecone/core-2020-05-10-deduplication huggingface dataset:
Scattering Forms and the Positive Geometry of Kinematics, Color and the
  Worldsheet

The search for a theory of the S-Matrix has revealed surprising geometric
structures underlying amplitudes ranging from the worldsheet to the
amplituhedron, but these are all geometries in auxiliary spaces as opposed to
kinematic space where amplitudes live. In this paper, we propose a novel
geometric understanding of amplitudes for a large class of theories. The key is
to think of amplitudes as differential forms directly on kinematic space. We
explore this picture for a wide range of massless theories in general spacetime
dimensions. For the bi-adjoint cubic scalar, we establish a direct connection
between its "scattering form" and a classic polytope--the associahedron--known
to mathematicians since the 1960's. We find an associahedron living naturally
in kinematic space, and the tree amplitude is simply the "canonical form"
associated with this "positive geometry". Basic physical properties such as
locality, unitarity and novel "soft" limits are fully determined by the
geometry. Furthermore, the moduli space for the open string worldsheet has also
long been recognized as an associahedron. We show that the scattering equations
act as a diffeomorphism between this old "worldsheet associahedron" and the new
"kinematic associahedron", providing a geometric interpretation and novel
derivation of the bi-adjoint CHY formula. We also find "scattering forms" on
kinematic space for Yang-Mills and the Non-linear Sigma Model, which are dual
to the color-dressed amplitudes despite having no explicit color factors. This
is possible due to a remarkable fact--"Color is Kinematics"--whereby kinematic
wedge products in the scattering forms satisfy the same Jacobi relations as
color factors. Finally, our scattering forms are well-defined on the
projectivized kinematic space, a property that provides a geometric origin for
color-kinematics duality.Comment: 77 pages, 25 figures; v2, corrected discussion of worldsheet
  associahedron canonical for
On the local structure of spacetime in ghost-free bimetric theory and
  massive gravity

The ghost-free bimetric theory describes interactions of gravity with another
spin-2 field in terms of two Lorentzian metrics. However, if the two metrics do
not admit compatible notions of space and time, the formulation of the initial
value problem becomes problematic. Furthermore, the interaction potential is
given in terms of the square root of a matrix which is in general nonunique and
possibly nonreal. In this paper we prove that the reality of the square root
matrix leads to a classification of the allowed metrics in terms of the
intersections of their null cones. Then, the requirement of general covariance
further constrains the allowed metrics to admit compatible notions of space and
time. It also leads to a unique definition of the square root matrix. The
restrictions are compatible with the equations of motion. These results ensure
that the ghost-free bimetric theory can be defined unambiguously and that the
two metrics always admit compatible 3+1 decompositions, at least locally. In
particular, these considerations rule out certain solutions of massive gravity
with locally Closed Causal Curves, which have been used to argue that the
theory is acausal.Comment: 35 pages, 7 figures; minor edits, added reference
On scalar and vector fields coupled to the energy-momentum tensor

We consider theories for scalar and vector _elds coupled to the energymomentum tensor. Since these _elds also carry a non-trivial energy-momentum tensor, the coupling prescription generates self-interactions. In analogy with gravity theories, we build the action by means of an iterative process that leads to an in_nite series, which can be resumed as the solution of a set of di_erential equations. We show that, in some particular cases, the equations become algebraic and that is also possible to _nd solutions in the form of polynomials. We briey review the case of the scalar _eld that has already been studied in the literature and extend the analysis to the case of derivative (disformal) couplings. We then explore theories with vector _elds, distinguishing between gaugeand non-gauge-invariant couplings. Interactions with matter are also considered, taking a scalar _eld as a proxy for the matter sector. We also discuss the ambiguity introduced by superpotential (boundary) terms in the de_nition of the energy-momentum tensor and use them to show that it is also possible to generate Galileon-like interactions with this procedure. We _nally use collider and astrophysical observations to set constraints on the dimensionful coupling which characterises the phenomenology of these models
Ghostbusters in $f(R)$ supergravity

$f(R)$ supergravity is known to contain a ghost mode associated with
higher-derivative terms if it contains $R^n$ with $n$ greater than two.We
remove the ghost in $f(R)$ supergravity by introducing auxiliary gauge field to
absorb the ghost. We dub this method as the ghostbuster
mechanism~\cite{Fujimori:2016udq}. We show that the mechanism removes the ghost
supermultiplet but also terms including $R^n$ with $n\geq3$, after integrating
out auxiliary degrees of freedom. For pure supergravity case, there appears an
instability in the resultant scalar potential. We then show that the
instability of the scalar potential can be cured by introducing matter
couplings in such a way that the system has a stable potential.Comment: 24 pages, v2: comments, references, new section added, version
  published in JHE
An analytic superfield formalism for tree superamplitudes in D=10 and
  D=11

Tree amplitudes of 10D supersymmetric Yang-Mills theory (SYM) and 11D
supergravity (SUGRA) are collected in multi-particle counterparts of analytic
on-shell superfields. These have essentially the same form as their chiral 4D
counterparts describing ${\cal N}=4$ SYM and ${\cal N}=8$ SUGRA, but with
components dependent on a different set of bosonic variables. These are the
D=10 and D=11 spinor helicity variables, the set of which includes the spinor
frame variable (Lorentz harmonics) and a scalar density, and generalized
homogeneous coordinates of the coset $\frac{SO(D-2)}{SO(D-4)\otimes U(1)}$
(internal harmonics).
  We present an especially convenient parametrization of the spinor harmonics
(Lorentz covariant gauge fixed with the use of an auxiliary gauge symmetry) and
use this to find (a gauge fixed version of) the 3-point tree superamplitudes of
10D SYM and 11D SUGRA which generalize the 4 dimensional anti-MHV
superamplitudes.Comment: LaTeX, 51pp. V2: improved and completed; to be published in JHEP;
  63p
Theoretical Uncertainties in the Calculation of Supersymmetric Dark
  Matter Observables

We estimate the current theoretical uncertainty in supersymmetric dark matter
predictions by comparing several state-of-the-art calculations within the
minimal supersymmetric standard model (MSSM). We consider standard neutralino
dark matter scenarios -- coannihilation, well-tempering, pseudoscalar resonance
-- and benchmark models both in the pMSSM framework and in frameworks with
Grand Unified Theory (GUT)-scale unification of supersymmetric mass parameters.
The pipelines we consider are constructed from the publicly available software
packages SOFTSUSY, SPheno, FeynHiggs, SusyHD, micrOMEGAs, and DarkSUSY. We find
that the theoretical uncertainty in the relic density as calculated by
different pipelines, in general, far exceeds the statistical errors reported by
the Planck collaboration. In GUT models, in particular, the relative
discrepancies in the results reported by different pipelines can be as much as
a few orders of magnitude. We find that these discrepancies are especially
pronounced for for cases where the dark matter physics relies critically on
calculations related to electroweak symmetry breaking, which we investigate in
detail, and for coannihilation models, where there is heightened sensitivity to
the sparticle spectrum. The dark matter annihilation cross section today and
the scattering cross section with nuclei also suffer appreciable theoretical
uncertainties, which, as experiments reach the relevant sensitivities, could
lead to uncertainty in conclusions regarding the viability or exclusion of
particular models.Comment: v2: minor changes, references adde
Good IR Duals of Bad Quiver Theories

The infrared dynamics of generic 3d N=4 bad theories (as per the
good-bad-ugly classification of Gaiotto and Witten) are poorly understood.
Examples of such theories with a single unitary gauge group and fundamental
flavors have been studied recently, and the low energy effective theory around
some special point in the Coulomb branch was shown to have a description in
terms of a good theory and a certain number of free hypermultiplets. A
classification of possible infrared fixed points for bad theories by Bashkirov,
based on unitarity constraints and superconformal symmetry, suggest a much
richer set of possibilities for the IR behavior, although explicit examples
were not known. In this note, we present a specific example of a bad quiver
gauge theory which admits a good IR description on a sublocus of its Coulomb
branch. The good description, in question, consists of two decoupled quiver
gauge theories with no free hypermultiplets.Comment: 20 pages, 3 figures. Discussion of the Coulomb branch singularities
  is further extende
Pure spinor superspace action for D=6, N=1 super-Yang-Mills theory

A Batalin-Vilkovisky action for D=6, N=1 super-Yang--Mills theory, including
coupling to hypermultiplets, is given. The formalism involves pure spinor
superfields. The geometric properties of the D=6, N=1 pure spinors (which
differ from Cartan pure spinors) are examined. Unlike the situation for
maximally supersymmetric models, the fields and antifields (including ghosts)
of the vector multiplet reside in separate superfields. The formalism provides
an off-shell superspace formulation for matter hypermultiplets, which in a
traditional treatment are on-shell.Comment: 16 p
Partition functions on 3d circle bundles and their gravity duals

The partition function of a three-dimensional $\mathcal{N} =2$ theory on the
manifold $\mathcal{M}_{g,p}$, an $S^1$ bundle of degree $p$ over a closed
Riemann surface $\Sigma_g$, was recently computed via supersymmetric
localization. In this paper, we compute these partition functions at large $N$
in a class of quiver gauge theories with holographic M-theory duals. We provide
the supergravity bulk dual having as conformal boundary such three-dimensional
circle bundles. These configurations are solutions to $\mathcal{N}=2$ minimal
gauged supergravity and pertain to the class of Taub-NUT-AdS and Taub-Bolt-AdS
preserving $1/4$ of the supersymmetries. We discuss the conditions for the
uplift of these solutions to M-theory, and compute the on-shell action via
holographic renormalization. We show that the uplift condition and on-shell
action for the Bolt solutions are correctly reproduced by the large $N$ limit
of the partition function of the dual superconformal field theory. In
particular, the $\Sigma_g \times S^1 \cong \mathcal{M}_{g,0}$ partition
function, which was recently shown to match the entropy of $AdS_4$ black holes,
and the $S^3 \cong \mathcal{M}_{0,1}$ free energy, occur as special cases of
our formalism, and we comment on relations between them.Comment: typos in eqs 5.51 and subsequent fixed, conclusions unaltere
Fermionic Halos at Finite Temperature in AdS/CFT

We explore the gravitational backreaction of a system consisting in a very
large number of elementary fermions at finite temperature, in asymptotically
AdS space. We work in the hydrodynamic approximation, and solve the
Tolman-Oppenheimer-Volkoff equations with a perfect fluid whose equation of
state takes into account both the relativistic effects of the fermionic
constituents, as well as its finite temperature effects. We find a novel 'dense
core-diluted halo' structure for the density profiles in the AdS bulk,
similarly as recently reported in flat space, for the case of astrophysical
dark matter halos in galaxies. We further study the critical equilibrium
configurations above which the core undergoes gravitational collapse towards a
massive black hole, and calculate the corresponding critical central
temperatures, for two qualitatively different central regimes of the fermions:
the diluted-Fermi case, and the degenerate case. As a probe for the dual CFT,
we construct the holographic two-point correlator of a scalar operator with
large conformal dimension in the worldline limit, and briefly discuss on the
boundary CFT effects at the critical points.Comment: 14 pages, 5 figure
6D Fractional Quantum Hall Effect

We present a 6D generalization of the fractional quantum Hall effect
involving membranes coupled to a three-form potential in the presence of a
large background four-form flux. The low energy physics is governed by a bulk
7D topological field theory of abelian three-form potentials with a single
derivative Chern-Simons-like action coupled to a 6D anti-chiral theory of
Euclidean effective strings. We derive the fractional conductivity, and explain
how continued fractions which figure prominently in the classification of 6D
superconformal field theories correspond to a hierarchy of excited states.
Using methods from conformal field theory we also compute the analog of the
Laughlin wavefunction. Compactification of the 7D theory provides a uniform
perspective on various lower-dimensional gapped systems coupled to boundary
degrees of freedom. We also show that a supersymmetric version of the 7D theory
embeds in M-theory, and can be decoupled from gravity. Encouraged by this, we
present a conjecture in which IIB string theory is an edge mode of a
10+2-dimensional bulk topological theory, thus placing all twelve dimensions of
F-theory on a physical footing.Comment: v2: 47 pages, 5 figures, clarifications and references adde
Holographic Heat engine within the framework of massive gravity

Heat engine models are constructed within the framework of massive gravity in
this paper. For the four-dimensional charged black holes in massive gravity, it
is shown that the heat engines have a higher efficiency for the cases $m^2>0$
than for the case $m=0$ when $c_1<0, c_2<0$. Considering a specific example, we
show that the maximum efficiency can reach $0.9219$ while the efficiency for
$m=0$ reads $0.5014$. The existence of graviton mass improves the heat engine
efficiency significantly. The situation is more complicated for the
five-dimensional neutral black holes. Not only the $c_1, c_2, m^2$ exert
influence on the efficiency, but also the constant $c_3$ corresponding to the
third massive potential contributes to the efficiency. When $c_1<0, c_2<0,
c_3<0$, the heat engine efficiency of the cases $m^2>0$ is higher than that of
the case $m=0$. By studying the ratio $\eta/\eta_C$, we also probe how the
massive gravity influences the behavior of the heat engine efficiency
approaching the Carnot efficiency.Comment: 9pages,4figure
DAMPE Electron-Positron Excess in Leptophilic $Z'$ model

Recently the DArk Matter Particle Explorer (DAMPE) has reported an excess in
the electron-positron flux of the cosmic rays which is interpreted as a dark
matter particle with the mass about $1.5$ TeV. We come up with a leptophilic
$Z'$ scenario including a Dirac fermion dark matter candidate which beside
explaining the observed DAMPE excess, is able to pass various
experimental/observational constraints including the relic density value from
the WMAP/Planck, the invisible Higgs decay bound at the LHC, the LEP bounds in
electron-positron scattering, the muon anomalous magnetic moment constraint,
Fermi-LAT data, and finally the direct detection experiment limits from the
XENON1t/LUX. By computing the electron-positron flux produced from a dark
matter with the mass about $1.5$ TeV we show that the model predicts the peak
observed by the DAMPE.Comment: 18 pages, 7 figures, matches with the published versio
Asymptotic Symmetries and Subleading Soft Photon Theorem in Effective
  Field Theories

In [1,2] it was shown that the subleading soft photon theorem in tree level
amplitudes in massless QED is equivalent to a new class of symmetries of the
theory parameterized by a vector field on the celestial sphere. In this paper,
we extend these results to the subleading soft photon theorem in any Effective
Field Theory containing photons and an arbitrary spectrum of massless
particles. We show that the charges associated to the above class of symmetries
are sensitive to certain three point functions of the theory and are corrected
by irrelevant operators of specific dimensions. Our analysis shows that the
subleading soft photon theorem in any tree level scattering amplitude is a
statement about asymptotic symmetries of the ${\cal S}$-matrix.Comment: 26 pages, 3 figure
From CFT to Ramond super-quantum curves

As we have shown in the previous work, using the formalism of matrix and
eigenvalue models, to a given classical algebraic curve one can associate an
infinite family of quantum curves, which are in one-to-one correspondence with
singular vectors of a certain (e.g. Virasoro or super-Virasoro) underlying
algebra. In this paper we reformulate this problem in the language of conformal
field theory. Such a reformulation has several advantages: it leads to the
identification of quantum curves more efficiently, it proves in full generality
that they indeed have the structure of singular vectors, it enables
identification of corresponding eigenvalue models. Moreover, this approach can
be easily generalized to other underlying algebras. To illustrate these
statements we apply the conformal field theory formalism to the case of the
Ramond version of the super-Virasoro algebra. We derive two classes of
corresponding Ramond super-eigenvalue models, construct Ramond super-quantum
curves that have the structure of relevant singular vectors, and identify
underlying Ramond super-spectral curves. We also analyze Ramond multi-Penner
models and show that they lead to supersymmetric generalizations of BPZ
equations.Comment: 72 page
Tree-level Quartic for a Holographic Composite Higgs

We present a new class of composite Higgs models where an adjustable
tree-level Higgs quartic coupling allows for a significant reduction in the
tuning of the Higgs potential. Our 5D warped space implementation is the first
example of a holographic composite Higgs model with a tree-level quartic. It is
inspired by a 6D model where the quartic originates from the Tr [A_5,A_6]^2
term of the gauge field strength, the same model that led to the original
little Higgs construction of Arkani-Hamed, Cohen, and Georgi. Beyond the
reduction of the tuning and the standard composite Higgs signatures, the model
predicts a doubling of the KK states with relatively small splittings as well
as a Higgs sector with two doublets in the decoupling limit.Comment: 22 pages, 4 figure
The Matrix Element Method at next-to-leading order QCD for hadronic
  collisions: Single top-quark production at the LHC as an example application

In a recent work the authors have presented a general algorithm to extend the
Matrix Element Method (MEM) to the hadronic production of coloured partons
taking into account next-to-leading-order (NLO) corrections in quantum
chromodynamics (QCD). In this article, the general algorithm is applied to the
production of single top quarks at the LHC. In particular, the generation of
unweighted events following the NLO predictions is presented. Treating these
events as the result of a toy experiment we illustrate the first application of
the Matrix Element Method at NLO QCD for hadronic jet production. As a concrete
example, we study the determination of the top-quark mass. We show that the
inclusion of the NLO corrections can lead to sizeable effects compared to the
Matrix Element Method relying on leading-order predictions only and that the
incorporation of the NLO corrections is mandatory to obtain reliable estimates
of the theoretical uncertainties. In addition, we find that measuring the
top-quark mass using the MEM in single top-quark production offers an
interesting alternative to mass measurements in top-quark pair production.Comment: references and clarifications added, typos corrected, matches
  published versio
On the power divergence in quasi gluon distribution function

Recent perturbative calculation of quasi gluon distribution function at
one-loop level shows the existence of extra linear ultraviolet divergences in
the cut-off scheme. We employ the auxiliary field approach, and study the
renormalization of gluon operators. The non-local gluon operator can mix with
new operators under renormalization, and the linear divergences in quasi
distribution function can be into the newly introduced operators. After
including the mixing, we find the improved quasi gluon distribution functions
contain only logarithmic divergences, and thus can be used to extract the gluon
distribution in large momentum effective theory.Comment: 18 pages, 10 figures. Published version in JHE
An Uplifting Discussion of T-Duality

It is well known that string theory has a T-duality symmetry relating circle
compactifications of large and small radius. This symmetry plays a foundational
role in string theory. We note here that while T-duality is order two acting on
the moduli space of compactifications, it is order four in its action on the
conformal field theory state space. More generally, involutions in the Weyl
group $W(G)$ which act at points of enhanced $G$ symmetry have canonical lifts
to order four elements of $G$, a phenomenon first investigated by J. Tits in
the mathematical literature on Lie groups and generalized here to conformal
field theory. This simple fact has a number of interesting consequences. One
consequence is a reevaluation of a mod two condition appearing in asymmetric
orbifold constructions. We also briefly discuss the implications for the idea
that T-duality and its generalizations should be thought of as discrete gauge
symmetries in spacetime.Comment: 47 pages, claims regarding $Z_4$ valued cocycles remove
Resummation for (boosted) top-quark pair production at NNLO+NNLL′ in QCD.

We construct predictions for top quark pair differential distributions at hadron colliders that combine state-of-the-art NNLO QCD calculations with double resummation at NNLL′ accuracy of threshold logarithms arising from soft gluon emissions and of small mass logarithms. This is the first time a resummed calculation at full NNLO+NNLL′ accuracy in QCD for a process with non-trivial color structure has been completed at the differential level. Of main interest to us is the stability of the  Mtt¯ and top-quark p T distributions in the boosted regime where fixed order calculations may become strongly dependent on the choice of dynamic scales. With the help of numeric and analytic arguments we confirm that the choice for the factorization and renormalization scales advocated recently by some of the authors is indeed optimal. We further derive a set of optimized kinematics-dependent scales for the matching functions which appear in the resummed calculations. Our NNLO+NNLL′ prediction for the top-pair invariant mass is significantly less sensitive to the choice of factorization scale than the fixed order prediction, even at NNLO. Notably, the resummed and fixed order calculations are in nearly perfect agreement with each other in the full  Mtt¯ range when the optimal dynamic scale is used. For the top-quark p T distribution the resummation performed here has less of an impact and instead we find that upgrading the matching with fixed-order from NLO+NNLL′ to NNLO+NNLL′ to be an important effect, a point to be kept in mind when using NLO-based Monte Carlo event generators to calculate this distribution