pinecone/core-2020-05-10-deduplication huggingface dataset:
Group theoretical interpretation of the modified gravity in de Sitter
  space

A frame work has been presented for theoretical interpretation of various
modified gravitational models which is based on the group theoretical approach
and unitary irreducible representations (UIR's) of de Sitter (dS) group. In
order to illustrate the application of the proposed method, a model of modified
gravity has been investigated. The background field method has been utilized
and the linearized modified gravitational field equation has been obtained in
the 4-dimensional dS space-time as the background. The field equation has been
written as the eigne-value equation of the Casimir operators of dS space using
the flat 5-dimensional ambient space notations. The Minkowskian correspondence
of the theory has been obtained by taking the zero curvature limit. It has been
shown that under some simple conditions, the linearized modified field equation
transforms according to two of the UIR's of dS group labeled by $\Pi^\pm_{2,1}$
and $\Pi^\pm_{2,2}$ in the discrete series. It means that the proposed modified
gravitational theory can be a suitable one to describe the quantum
gravitational effects in its linear approximation on dS space. The field
equation has been solved and the solution has been written as the
multiplication of a symmetric rank-2 polarization tensor and a massless scalar
field using the ambient space notations. Also the two-point function has been
calculated in the ambient space formalism. It is dS invariant and free of any
theoretical problem.Comment: 20 page
Triplet-Quadruplet Dark Matter

We explore a dark matter model extending the standard model particle content
by one fermionic $SU(2)_L$ triplet and two fermionic $SU(2)_L$ quadruplets,
leading to a minimal realistic UV-complete model of electroweakly interacting
dark matter which interacts with the Higgs doublet at tree level via two kinds
of Yukawa couplings. After electroweak symmetry-breaking, the physical spectrum
of the dark sector consists of three Majorana fermions, three singly charged
fermions, and one doubly charged fermion, with the lightest neutral fermion
$\chi_1^0$ serving as a dark matter candidate. A typical spectrum exhibits a
large degree of degeneracy in mass between the neutral and charged fermions,
and we examine the one-loop corrections to the mass differences to ensure that
the lightest particle is neutral. We identify regions of parameter space for
which the dark matter abundance is saturated for a standard cosmology,
including coannihilation channels, and find that this is typically achieved for
$m_{\chi_1^0}\sim 2.4~\mathrm{TeV}$. Constraints from precision electroweak
measurements, searches for dark matter scattering with nuclei, and dark matter
annihilation are important, but leave open a viable range for a thermal relic.Comment: 27 pages, 6 figures. v2: minor revisions to match published versio
Future Collider Signatures of the Possible 750 GeV State

If the recent indications of a possible state $\Phi$ with mass $\sim 750$ GeV
decaying into two photons reported by ATLAS and CMS in LHC collisions at 13 TeV
were to become confirmed, the prospects for future collider physics at the LHC
and beyond would be affected radically, as we explore in this paper. Even
minimal scenarios for the $\Phi$ resonance and its $\gamma \gamma$ decays
require additional particles with masses $\gtrsim \frac12 m_\Phi$. We consider
here two benchmark scenarios that exemplify the range of possibilities: one in
which $\Phi$ is a singlet scalar or pseudoscalar boson whose production and
$\gamma \gamma$ decays are due to loops of coloured and charged fermions, and
another benchmark scenario in which $\Phi$ is a superposition of (nearly)
degenerate CP-even and CP-odd Higgs bosons in a (possibly supersymmetric)
two-Higgs doublet model also with additional fermions to account for the
$\gamma \gamma$ decay rate. We explore the implications of these benchmark
scenarios for the production of $\Phi$ and its new partners at colliders in
future runs of the LHC and beyond, at higher-energy $pp$ colliders and at $e^+
e^-$ and $\gamma \gamma$ colliders, with emphasis on the bosonic partners
expected in the doublet scenario and the fermionic partners expected in both
scenarios.Comment: 52 pages, 24 figures, v2 corrects two plots and some typos, and
  contains a new section on production in electron-positron collisions as well
  as additional reference
Leptogenesis and residual CP symmetry

We discuss flavour dependent leptogenesis in the framework of lepton flavour
models based on discrete flavour and CP symmetries applied to the type-I seesaw
model. Working in the flavour basis, we analyse the case of two general
residual CP symmetries in the neutrino sector, which corresponds to all
possible semi-direct models based on a preserved $Z_2$ in the neutrino sector,
together with a CP symmetry, which constrains the PMNS matrix up to a single
free parameter which may be fixed by the reactor angle. We systematically study
and classify this case for all possible residual CP symmetries, and show that
the $R$-matrix is tightly constrained up to a single free parameter, with only
certain forms being consistent with successful leptogenesis, leading to
possible connections between leptogenesis and PMNS parameters. The formalism is
completely general in the sense that the two residual CP symmetries could
result from any high energy discrete flavour theory which respects any CP
symmetry. As a simple example, we apply the formalism to a high energy $S_4$
flavour symmetry with a generalized CP symmetry, broken to two residual CP
symmetries in the neutrino sector, recovering familiar results for PMNS
predictions, together with new results for flavour dependent leptogenesis.Comment: 35 pages, 8 figure
Testing the light dark matter scenario of the MSSM at the LHC

In the light dark matter (DM) scenario of the MSSM, the DM relic density puts
non-trivial requirements on the spectrum of supersymmetric particles. As a
result, the direct search for multi-lepton signals at the LHC has great impact
on the scenario. In this work, we concentrate on the searches for sleptons and
electroweak-inos at the LHC, and investigate the constraints on the light DM
scenario from the 8 TeV LHC data as well as the capability of the 14 TeV LHC to
test the scenario. We first get the samples of the scenario by scanning the
vast parameter space of the MSSM and considering some easily available
constraints, such as those from the DM relic density, the LUX experiment and
the Higgs searches at colliders. Then for the surviving samples, we simulate
the $2l+E_T^{miss}$ signal from slepton pair production process and the
$2l+E_T^{miss}$ and $3l+E_T^{miss}$ signals from chargino and neutralino
associated production processes at both the 8 TeV LHC and the 14 TeV LHC. Our
simulations indicate that the 8 TeV LHC has excluded a sizable portion of the
samples, and the 14 TeV LHC can be even much more powerful in testing the
scenario. For example, in case that no multi-lepton signals are observed at the
14 TeV LHC, most samples of the light DM scenario will be excluded, especially
a lower limit on the lightest neutralino mass will be set at 42 GeV and 44 GeV
with 30 $fb^{-1}$ and 100 $fb^{-1}$ data respectively, and this limit can be
further pushed up to $55\ {\rm GeV}$ with 300 $fb^{-1}$ data.Comment: 20 pages, 4 figure
3D holography: from discretum to continuum

We study the one-loop partition function of 3D gravity without cosmological
constant on the solid torus with arbitrary metric fluctuations on the boundary.
To this end we employ the discrete approach of (quantum) Regge calculus. In
contrast with similar calculations performed directly in the continuum, we work
with a boundary at finite distance from the torus axis. We show that after
taking the continuum limit on the boundary - but still keeping finite distance
from the torus axis - the one-loop correction is the same as the one recently
found in the continuum in Barnich et al. for an asymptotically flat boundary.
The discrete approach taken here allows to identify the boundary degrees of
freedom which are responsible for the non-trivial structure of the one-loop
correction. We therefore calculate also the Hamilton-Jacobi function to
quadratic order in the boundary fluctuations both in the discrete set-up and
directly in the continuum theory. We identify a dual boundary field theory with
a Liouville type coupling to the boundary metric. The discrete set-up allows
again to identify the dual field with degrees of freedom associated to radial
bulk edges attached to the boundary. Integrating out this dual field reproduces
the (boundary diffeomorphism invariant part of the) quadratic order of the
Hamilton-Jacobi functional. The considerations here show that bulk boundary
dualities might also emerge at finite boundaries and moreover that discrete
approaches are helpful in identifying such dualities.Comment: 42 page
The Electromagnetic Decays of $B^{\pm}_c(2S)$

We calculate the electromagnetic (EM) decay widths of the $B^{\pm}_c(2S)$
meson, which is observed recently by the ATLAS Collaboration. The main EM decay
channels of this particle are $1{^3S_1}\gamma$ and $1{P}\gamma$, which, in
literature, are estimated to have the branching ratio of about $1/10$. In this
work, we get the partial decay widths: $\Gamma(2{^1S_0}\rightarrow
1{^3S_1}\gamma)=0.192$ keV, $\Gamma(2{^1S_0}\rightarrow 1{P_1}\gamma) = 2.24$
keV and $\Gamma(2{^1S_0}\rightarrow 1{P_1^\prime}\gamma) = 11.4$ keV. In the
calculation, the instantaneous approximated Bethe-Salpeter method is used. For
the $P$-wave $B_c$ mesons, the wave functions are given by mixing the $^3P_1$
and $^1P_1$ states. Within the Mandelstam formalism, the decay amplitude is
given, which includes the relativistic corrections.Comment: 9 pages, 3 figures, 3 table
Non-Abelian chiral instabilities at high temperature on the lattice

We report on an exploratory lattice study on the phenomenon of chiral
instabilities in non-Abelian gauge theories at high temperature. It is based on
a recently constructed anomalous Langevin-type effective theory of classical
soft gauge fields in the presence of a chiral number density $n_5=n_{\rm
R}-n_{\rm L}$. Evaluated in thermal equilibrium using classical lattice
techniques it reveals that the fluctuating soft fields indeed exhibit a rapid
energy increase at early times and we observe a clear dependence of the
diffusion rate of topological charge (sphaleron rate) on the the initial $n_5$,
relevant in both early universe baryogenesis and relativistic heavy-ion
collisions. The topological charge furthermore shows a drift among distinct
vacuum sectors, roughly proportional to the initial $n_5$ and in turn the
chiral imbalance is monotonously reduced as required by helicity conservation.Comment: 35 pages, 13 figure
Fundamental Composite 2HDM: SU(N) with 4 flavours

We present a new model of composite Higgs based on a gauged SU(N) group with
4 Dirac fermions in the fundamental representation. At low energy, the model
has a global symmetry SU(4)$\times$SU(4) broken to the diagonal SU(4),
containing 2 Higgs doublets in the coset. We study in detail the generation of
the top mass via 4-fermion interactions, and the issue of the vacuum alignment.
In particular, we prove that, without loss of generality, the vacuum can always
be aligned with one doublet. Under certain conditions on the top pre-Yukawas,
the second doublet, together with the additional triplets, is stable and can
thus play the role of Dark Matter. This model can therefore be an example of
composite inert-2HDM model.Comment: 34 pages, 2 figure
On level crossing in conformal field theories

We study the properties of operators in a unitary conformal field theory
whose scaling dimensions approach each other for some values of the parameters
and satisfy von Neumann-Wigner non-crossing rule. We argue that the scaling
dimensions of such operators and their OPE coefficients have a universal
scaling behavior in the vicinity of the crossing point. We demonstrate that the
obtained relations are in a good agreement with the known examples of the
level-crossing phenomenon in maximally supersymmetric $\mathcal N=4$ Yang-Mills
theory, three-dimensional conformal field theories and QCD.Comment: 20 pages, 4 figures; v2: minor corrections, references adde
Semi-Inclusive Wino and Higgsino Annihilation to LL'

We systematically compute the annihilation rate for winos and higgsinos into
the final state relevant for indirect detection experiments, gamma + X. The
radiative corrections to this process receive enhancement from the large
Bloch-Nordsieck-Violating Sudakov logarithm, log(2 M_chi/M_W). We resum the
double logs and include single logs to fixed order using a formalism that
combines nonrelativistic and soft-collinear effective field theories. For the
wino case, we update an earlier exclusion adapting results of the HESS
experiment. At the thermal relic mass of 3 TeV, LL' corrections result in a
~30% reduction in rate relative to LL. Nonetheless, single logs do not save the
wino, and it is still excluded by an order of magnitude. Experimental cuts
produce an endpoint region which, our results show, significantly effects the
higgsino rate at its thermal-relic mass near 1 TeV and is deserving of further
study.Comment: 29 pages, 10 figure
P-wave holographic superconductor/insulator phase transitions affected
  by dark matter sector

The holographic approach to building the p-wave superconductors results in
three different models: the Maxwell-vector, the SU(2) Yang-Mills and the
helical. In the probe limit approximation, we analytically examine the
properties of the first two models in the theory with {\it dark matter} sector.
It turns out that the effect of {\it dark matter} on the Maxwell-vector p-wave
model is the same as on the s-wave superconductor studied earlier. For the
non-Abelian model we study the phase transitions between p-wave holographic
insulator/superconductor and metal/superconductor.
  Studies of marginally stable modes in the theory under consideration allow us
to determine features of p-wave holographic droplet in a constant magnetic
field. The dependence of the superconducting transition temperature on the
coupling constant $\alpha$ to the {\it dark matter} sector is affected by the
{\it dark matter} density $\rho_D$. For $\rho_D>\rho$ the transition
temperature is a decreasing function of $\alpha$. The critical chemical
potential $\mu_c$ for the quantum phase transition between insulator and metal
depends on the chemical potential of dark matter $\mu_D$ and for $\mu_D=0$ is a
decreasing function of $\alpha$.Comment: 25 pages, 3 figures, JHEP style (included), version accepted for
  publication in JHE
New signatures and limits on R-parity violation from resonant squark
  production

We discuss resonant squark production at the LHC via baryonic $R$-parity
violating interactions. The cross section easily exceeds pair-production and a
new set of signatures can be used to probe squarks, particularly stops. These
include dijet resonances, same-sign top quarks and four-jet resonances with
large $b$-jet multiplicities, as well as the possibility of displaced
neutralino decays. We use publicly available searches at $\sqrt{s}=8$ TeV and
first results from collisions at $\sqrt{s}=13$ TeV to set upper limits on
$R$-parity violating couplings, with particular focus on simplified models with
light stops and neutralinos. The exclusion reach of these signatures is
comparable to $R$-parity-conserving searches, $m_{\tilde t}\simeq 500-700$ GeV.
In addition, we find that O(1) couplings involving the stop can be excluded
well into the multi-TeV range, and stress that new searches for single- and
pair-produced four-jet resonances will be necessary to exclude sub-TeV stops
for a natural SUSY spectrum with light higgsinos.Comment: v4: fixed arXiv links in references. v3: version to appear in JHEP.
  References and comments added. 28 pages, 11 figures + appendice
Perturbative computation of string one-loop corrections to Wilson loop
  minimal surfaces in $AdS_5 \times S^5$

We revisit the computation of the 1-loop string correction to the "latitude"
minimal surface in $AdS_5 \times S^5$ representing 1/4 BPS Wilson loop in
planar $\cal N$=4 SYM theory previously addressed in arXiv:1512.00841 and
arXiv:1601.04708. We resolve the problem of matching with the subleading term
in the strong coupling expansion of the exact gauge theory result (derived
previously from localization) using a different method to compute determinants
of 2d string fluctuation operators. We apply perturbation theory in a small
parameter (angle of the latitude) corresponding to an expansion near the
$AdS_2$ minimal surface representing 1/2 BPS circular Wilson loop. This allows
us to compute the corrections to the heat kernels and zeta-functions of the
operators in terms of the known heat kernels on $AdS_2$. We apply the same
method also to two other examples of Wilson loop surfaces: generalized cusp and
$k$-wound circle.Comment: 32 pages, one reference added, typos correcte
A geometric formulation of exceptional field theory

We formulate the full bosonic SL(5) exceptional field theory in a
coordinate-invariant manner. Thereby we interpret the 10-dimensional extended
space as a manifold with $\mathrm{SL}(5)\times\mathbb{R}^+$-structure. We show
that the algebra of generalised diffeomorphisms closes subject to a set of
closure constraints which are reminiscent of the quadratic and linear
constraints of maximal seven-dimensional gauged supergravities, as well as the
section condition. We construct an action for the full bosonic SL(5)
exceptional field theory, even when the
$\mathrm{SL}(5)\times\mathbb{R}^+$-structure is not locally flat.Comment: 46 page
Gravitino or Axino Dark Matter with Reheat Temperature as high as
  $10^{16}$ GeV

A new scheme for lightest supersymmetric particle (LSP) dark matter is
introduced and studied in theories of TeV supersymmetry with a QCD axion, $a$,
and a high reheat temperature after inflation, $T_R$. A large overproduction of
axinos ($\tilde{a}$) and gravitinos ($\tilde{G}$) from scattering at $T_R$, and
from freeze-in at the TeV scale, is diluted by the late decay of a saxion
condensate that arises from inflation. The two lightest superpartners are
$\tilde{a}$, with mass of order the TeV scale, and $\tilde{G}$ with mass
$m_{3/2}$ anywhere between the keV and TeV scales, depending on the mediation
scale of supersymmetry breaking. Dark matter contains both warm and cold
components: for $\tilde{G}$ LSP the warm component arises from $\tilde{a}
\rightarrow \tilde{G}a$, while for $\tilde{a}$ LSP the warm component arises
from $\tilde{G} \rightarrow \tilde{a}a$. The free-streaming scale for the warm
component is predicted to be of order 1 Mpc (and independent of $m_{3/2}$ in
the case of $\tilde{G}$ LSP). $T_R$ can be as high as $10^{16}$ GeV, for any
value of $m_{3/2}$, solving the gravitino problem. The PQ symmetry breaking
scale $V_{PQ}$ depends on $T_R$ and $m_{3/2}$ and can be anywhere in the range
$(10^{10} - 10^{16})$ GeV. Detailed predictions are made for the lifetime of
the neutralino LOSP decaying to $\tilde{a}+ h/Z$ and $\tilde{G}+h/Z/\gamma$,
which is in the range of $(10^{-1}-10^6)$m over much of parameter space. For an
axion misalignment angle of order unity, the axion contribution to dark matter
is sub-dominant, except when $V_{PQ}$ approaches $10^{16}$ GeV.Comment: 43 pages, 16 figure
Dimensional reduction of the Standard Model coupled to a new singlet
  scalar field

We derive an effective dimensionally reduced theory for the Standard Model
augmented by a real singlet scalar. We treat the singlet as a superheavy field
and integrate it out, leaving an effective theory involving only the Higgs and
$\mathrm{SU}(2)_\mathrm{L} \times \mathrm{U}(1)_Y$ gauge fields, identical to
the one studied previously for the Standard Model. This opens up the
possibility of efficiently computing the order and strength of the electroweak
phase transition, numerically and nonperturbatively, in this extension of the
Standard Model. Understanding the phase diagram is crucial for models of
electroweak baryogenesis and for studying the production of gravitational waves
at thermal phase transitions.Comment: 52 pages, 3 figures; v2: references added, additional discussion of
  temporal gluons, discussion extended with some parameter space scans,
  published in JHE
Second level semi-degenerate fields in W3 Toda theory: matrix element
  and differential equation

In a recent study we considered W3 Toda 4-point functions that involve matrix
elements of a primary field with the highest-weight in the adjoint
representation of sl3. We generalize this result by considering a
semi-degenerate primary field, which has one null vector at level two. We
obtain a sixth-order Fuchsian differential equation for the conformal blocks.
We discuss the presence of multiplicities, the matrix elements and the fusion
rules.Comment: 22 pages. Published JHEP version: Typos corrected, references added.
  Section 5.2.3 adde
Vector resonances at LHC Run II in composite 2HDM

We consider a model where the electroweak symmetry breaking is driven by
strong dynamics, resulting in an electroweak doublet scalar condensate, and
transmitted to the standard model matter fields via another electroweak doublet
scalar. At low energies the effective theory therefore shares features with a
type-I two Higgs doublet model. However, important differences arise due to the
rich composite spectrum expected to contain new vector resonances accessible at
the LHC. We carry out a systematic analysis of the vector resonance signals at
LHC and find that the model remains viable, but will be tightly constrained by
direct searches as the projected integrated luminosity, around 200 fb$^{-1}$,
of the current run becomes available.Comment: 15 pages, 5 figures: eqs.4,7,13-17 and fig.4 added, text revised and
  extended; version to appear on JHE
Heat engine in the three-dimensional spacetime

We define a kind of heat engine via three-dimensional charged BTZ black
holes. This case is quite subtle and needs to be more careful. The heat flow
along the isochores does not equal to zero since the specific heat $C_V\neq0$
and this point completely differs from the cases discussed before whose
isochores and adiabats are identical. So one cannot simply apply the paradigm
in the former literatures. However, if one introduces a new thermodynamic
parameter associated with the renormalization length scale, the above problem
can be solved. We obtain the analytical efficiency expression of the
three-dimensional charged BTZ black hole heat engine for two different schemes.
Moreover, we double check with the exact formula. Our result presents the first
specific example for the sound correctness of the exact efficiency formula. We
argue that the three-dimensional charged BTZ black hole can be viewed as a toy
model for further investigation of holographic heat engine. Furthermore, we
compare our result with that of the Carnot cycle and extend the former result
to three-dimensional spacetime. In this sense, the result in this paper would
be complementary to those obtained in four-dimensional spacetime or ever
higher. Last but not the least, the heat engine efficiency discussed in this
paper may serve as a criterion to discriminate the two thermodynamic approaches
introduced in Ref.[29] and our result seems to support the approach which
introduces a new thermodynamic parameter $R=r_0$.Comment: Revised version. Discussions adde