pinecone/core-2020-05-10-deduplication huggingface dataset:
Landau-Ginzburg skeletons

We study the class of indecomposable two-dimensional Landau-Ginzburg theories
with (2,2) supersymmetry and central charge c < 6 with the aim of classifying
all such theories up to marginal deformations. Our results include cases
overlooked in previous classifications. The results are rigorous for three or
fewer fields and more generally are rigorous if we assume an extra bound.
Numerics suggest that we have the complete set of indecomposable
Landau-Ginzburg families with c<6. This set consists of 38 infinite families
and a finite list of 418 sporadic cases. The basic tools are classic results of
Kreuzer and Skarke on quasi-homogeneous isolated singularities and solutions to
certain feasibility integer programming problems.Comment: 39 pages and tikz figures, three text files with LG charges included
  in submission; v2 fixes two sets of charge
A holographic perspective on phonons and pseudo-phonons

We analyze the concomitant spontaneous breaking of translation and conformal
symmetries by introducing in a CFT a complex scalar operator that acquires a
spatially dependent expectation value. The model, inspired by the holographic
Q-lattice, provides a privileged setup to study the emergence of phonons from a
spontaneous translational symmetry breaking in a conformal field theory and
offers valuable hints for the treatment of phonons in QFT at large. We first
analyze the Ward identity structure by means of standard QFT techniques,
considering both spontaneous and explicit symmetry breaking. Next, by
implementing holographic renormalization, we show that the same set of Ward
identities holds in the holographic Q-lattice. Eventually, relying on the
holographic and QFT results, we study the correlators realizing the symmetry
breaking pattern and how they encode information about the low-energy spectrum.Comment: 31+1 pages, version accepted on JHE
A Modern Approach to Superradiance

In this paper, we provide a simple and modern discussion of rotational
superradiance based on quantum field theory. We work with an effective theory
valid at scales much larger than the size of the spinning object responsible
for superradiance. Within this framework, the probability of absorption by an
object at rest completely determines the superradiant amplification rate when
that same object is spinning. We first discuss in detail superradiant
scattering of spin 0 particles with orbital angular momentum $\ell=1$, and then
extend our analysis to higher values of orbital angular momentum and spin.
Along the way, we provide a simple derivation of vacuum friction---a "quantum
torque" acting on spinning objects in empty space. Our results apply not only
to black holes but to arbitrary spinning objects. We also discuss superradiant
instability due to formation of bound states and, as an illustration, we
calculate the instability rate $\Gamma$ for bound states with massive spin 1
particles. For a black hole with mass $M$ and angular velocity $\Omega$, we
find $\Gamma \sim (G M \mu)^7 \Omega$ when the particle's Compton wavelength
$1/\mu$ is much greater than the size $GM$ of the spinning object. This rate is
parametrically much larger than the instability rate for spin 0 particles,
which scales like $(GM \mu)^9 \Omega$. This enhanced instability rate can be
used to constrain the existence of ultralight particles beyond the Standard
Model.Comment: 39 pages (v2 contains many added details and corrects an error in v1.
  In particular, the instability rates for leading vector bound states are
  computed exactly in the large Compton wavelength limit.
Partition function of free conformal fields in 3-plet representation

Simplest examples of AdS/CFT duality correspond to free CFTs in d dimensions
with fields in vector or adjoint representation of an internal symmetry group
dual in the large N limit to a theory of massless or massless plus massive
higher spins in AdS_{d+1}. One may also study generalizations when conformal
fields belong to higher dimensional representations, i.e. carry more than two
internal symmetry indices. Here we consider the case of the 3-fundamental
("3-plet") representation. One motivation is a conjectured connection to
multiple M5-brane theory: heuristic arguments suggest that it may be related to
an (interacting) CFT of 6d (2,0) tensor multiplets in 3-plet representation of
large N symmetry group that has an AdS_7 dual. We compute the singlet partition
function Z on S^1 x S^{d-1} for a free field in 3-plet representation of U(N)
and analyse its novel large N behaviour. The large N limit of the low
temperature expansion of Z which is convergent in the vector and adjoint cases
here is only asymptotic, reflecting the much faster growth of the number of
singlet operators with dimension, indicating a phase transition at very low
temperature. Indeed, while the critical temperatures in the vector (T_c ~ N^a,
a >0) and adjoint (T_c ~ 1) cases are finite, we find that in the 3-plet case
T_c ~ 1/ log N, i.e. it approaches zero at large N. We discuss some details of
large N solution for the eigenvalue distribution. Similar conclusions apply to
higher p-plet representations of U(N) or O(N) and also to the free p-tensor
theories invariant under [U(N)]^p or [O(N)]^p starting with p=3.Comment: 41 pages, several figures. v2: references added. v3: minor
  correction
Gravitational echoes from macroscopic quantum gravity effects

New theoretical approaches developed in the last years predict that
macroscopic quantum gravity effects in black holes should lead to modifications
of the gravitational wave signals expected in the framework of classical
general relativity, with these modifications being characterized by the
existence of dampened repetitions of the primary signal. Here we use the fact
that non-perturbative corrections to the near-horizon external geometry of
black holes are necessary for these modifications to exist, in order to
classify different proposals and paradigms with respect to this criterion and
study in a neat and systematic way their phenomenology. Proposals that lead
naturally to the existence of echoes in the late-time ringdown of gravitational
wave signals from black hole mergers must share the replacement of black holes
by horizonless configurations with a physical surface showing reflective
properties in the relevant range of frequencies. On the other hand, proposals
or paradigms that restrict quantum gravity effects on the external geometry to
be perturbative, such as black hole complementarity or the closely related
firewall proposal, do not display echoes. For the sake of completeness we
exploit the interplay between the timescales associated with the formation of
firewalls and the mechanism behind the existence of echoes in order to conclude
that even unconventional distortions of the firewall concept (such as naked
firewalls) do not lead to this phenomenon.Comment: V1: 21 pages + references, 1 figure. V2: updated reference
Probing Lepton Flavor Violation at the 13 TeV LHC

We investigate the bounds on tau-mu lepton flavor violation (LFV). Our main
focus is on the collider constrains on tau-mu LFV. We use the Type-III
Two-Higgs-Doublet-Model (2HDM) as a set up for our study. While the LFV
branching fraction of the 125 GeV is well constrained by current LHC searches,
the heavier neutral states could have a large branching fraction to tau and
muon. We estimate the LHC reach for the 13 TeV center of mass energy with 300
$\text{fb}^{-1}$ luminosity for a neutral boson decaying into a tau and a muon.
We identify parts of the LFV parameter space where the searches for heavy
scalar and pseudoscalar decaying into a tau and a muon are more sensitive than
the similar search for the 125 GeV boson.Comment: 29 + 3 pages, 23 figures. Version 2 expanded discussion of low energy
  constraints and added more references. Matched the JHEP versio
On the gl(1|1) Wess-Zumino-Witten Model

We continue the study of the gl(1|1) Wess-Zumino-Witten model. The
Knizhnik-Zamolodchikov equations for the one, two, three and four point
functions are analyzed, for vertex operators corresponding to typical and
projective representations. We illustrate their interplay with the logarithmic
global conformal Ward identities. We compute the four point function for one
projective and three typical representations. Three coupled first order
Knizhnik-Zamolodchikov equations are integrated consecutively in terms of
generalized hypergeometric functions, and we assemble the solutions into a
local correlator. Moreover, we prove crossing symmetry of the four point
function of four typical representations at generic momenta. Throughout, the
map between the gl(1|1) Wess-Zumino-Witten model and symplectic fermions is
exploited and extended.Comment: 37 page
Shift-symmetries and gauge coupling functions in orientifolds and
  F-theory

We investigate the field dependence of the gauge coupling functions of
four-dimensional Type IIB orientifold and F-theory compactifications with
space-time filling seven-branes. In particular, we analyze the constraints
imposed by holomorphicity and covariance under shift-symmetries of the bulk and
brane axions. This requires introducing quantum corrections that necessarily
contain Riemann theta functions on the complex torus spanned by the D7-brane
Wilson line moduli. Our findings hint towards a new underlying geometric
structure for gauge coupling functions in string compactifications. We
generalize this discussion to a genuine F-theory compactification on an
elliptically fibered Calabi-Yau fourfold. We perform the first general
dimensional reduction of eleven-dimensional supergravity and dualization to the
F-theory frame. The resulting effective action is compared with the circle
reduction of a four-dimensional N=1 supergravity theory. The F-theory geometry
elegantly unifies bulk and brane degrees of freedom and allows us to infer
non-trivial results about holomorphicity and shift-symmetries. For instance, we
gain new insight into kinetic mixing of bulk and brane gauge fields.Comment: 48 pages. v2: minor correction
BMS Supertranslations and Not So Soft Gravitons

In a previous article, we have argued that Low's sub-leading soft photon
theorem can be recovered as a Ward identity associated to the same large gauge
transformations that control the leading piece of the theorem. The key for that
was to link the energy expansion displayed in the soft theorem to a
$\frac{1}{r}$ expansion that we can perform in the associated asymptotic
charge. We expect this idea to be valid in general, and here we provide
compelling evidence for it by showing how the same method works in the case of
Einstein-Hilbert gravity. More precisely, we are able to derive the three
orders of the tree-level soft graviton theorem simply from the BMS
supertranslation charge, known to give rise to the leading soft graviton
theorem. In particular, we do not need to invoke superrotations (nor extended
superrotations) at any point of the argument.Comment: v2: 26 pages, moderate revision with corrections and clarifications,
  refs adde
Goldstino superfields in N=2 supergravity

We present off-shell N=2 supergravity actions, which exhibit spontaneously
broken local supersymmetry and allow for de Sitter vacua for certain values of
the parameters. They are obtained by coupling the standard N=2
supergravity-matter systems to the Goldstino superfields introduced in
arXiv:1105.3001 and arXiv:1607.01277 in the rigid supersymmetric case. These
N=2 Goldstino superfields include nilpotent chiral and linear supermultiplets.
We also describe a new reducible N=1 Goldstino supermultiplet.Comment: 40 pages; V2: minor corrections, references added, published versio
A Supersymmetric SYK-like Tensor Model

We consider a supersymmetric SYK-like model without quenched disorder that is
built by coupling two kinds of fermionic N=1 tensor-valued superfields,
"quarks" and "mesons". We prove that the model has a well-defined large-N limit
in which the (s)quark 2-point functions are dominated by mesonic "melon"
diagrams. We sum these diagrams to obtain the Schwinger-Dyson equations and
show that in the IR, the solution agrees with that of the supersymmetric SYK
model.Comment: 29 pages, 19 figures. v2: 3 references and more details of the
  computation in section 3.1 are adde
On entanglement spreading from holography

A global quench is an interesting setting where we can study thermalization
of subsystems in a pure state. We investigate entanglement entropy (EE) growth
in global quenches in holographic field theories and relate some of its aspects
to quantities characterizing chaos. More specifically we obtain four key
results:
  1. We prove holographic bounds on the entanglement velocity $v_E$ and the
butterfly effect speed $v_B$ that arises in the study of chaos.
  2. We obtain the EE as a function of time for large spherical entangling
surfaces analytically. We show that the EE is insensitive to the details of the
initial state or quench protocol.
  3. In a thermofield double state we determine analytically the two-sided
mutual information between two large concentric spheres separated in time.
  4. We derive a bound on the rate of growth of EE for arbitrary shapes, and
develop an expansion for EE at early times.
  In a companion paper arXiv:1608.05101, we put these results in the broader
context of EE growth in chaotic systems: we relate EE growth to the chaotic
spreading of operators, derive bounds on EE at a given time, and compare the
holographic results to spin chain numerics and toy models. In this paper, we
perform holographic calculations that provide the basis of arguments presented
in that paper.Comment: v2: presentation improved, typos fixed, 54 pages, 17 figures v1: 53
  pages, 16 figure
On entanglement spreading in chaotic systems

We discuss the time dependence of subsystem entropies in interacting quantum
systems. As a model for the time dependence, we suggest that the entropy is as
large as possible given two constraints: one follows from the existence of an
emergent light cone, and the other is a conjecture associated to the
"entanglement velocity" $v_E$. We compare this model to new holographic and
spin chain computations, and to an operator growth picture. Finally, we
introduce a second way of computing the emergent light cone speed in
holographic theories that provides a boundary dynamics explanation for a
special case of entanglement wedge subregion duality in AdS/CFT.Comment: v2: small adjustments in the presentation, typos fixed, references
  added; v1: 25 pages, 10 figure
Profile of multiboson signals

We investigate the visibility of signals characterised by wide bumps over a
smoothly falling background that cannot be accurately predicted by Monte Carlo
calculations. Examples of such are the wide bumps that triboson and quadriboson
resonance cascade decays would yield in diboson resonance searches in fully
hadronic final states. We find that the sensitivity to triboson bumps is rather
small: signals of a moderate size could be present in current data and yet
remain unnoticed. For quadriboson cascade decays the signals can hardly be
distinguished from the background in the current searches.Comment: LaTeX 17 pages. v2: fixed typos and comments added; journal versio
Flavor origin of dark matter and its relation with leptonic nonzero
  $\theta_{13}$ and Dirac CP phase $\delta$

We propose a minimal extension of the standard model by including a $U(1)$
flavor symmetry to establish a correlation between the relic abundance of dark
matter, measured by WMAP and PLANCK satellite experiments and non-zero value of
$\sin \theta_{13}$ observed at DOUBLE CHOOZ, Daya Bay, RENO and T2K. The
flavour symmetry is allowed to be broken at a high scale to a remnant
$\mathcal{Z}_2$ symmetry, which not only ensures the stability to the dark
matter, but also gives rise to a modification to the existing $A_4$-based
tri-bimaximal neutrino mixing. This deviation in turn suggests the required
non-zero value of $\sin \theta_{13}$. We assume the dark matter to be neutral
under the existing $A_4$ symmetry while charged under the $U(1)$ flavor
symmetry. Hence in this set-up, the non-zero value of $\sin \theta_{13}$
predicts the dark matter charge under $U(1)$, which can be tested at various
ongoing and future direct and collider dark matter search experiments. We also
point out the involvement of nonzero leptonic CP phase $\delta$, which plays an
important role in the analysis.Comment: 25 pages, 17 figures, published versio
Manifestly T-dual formulation of AdS space

We present a manifestly T-dual formulation of curved spaces such as an AdS
space. For group manifolds related by the orthogonal vielbein fields the three
form H=dB in the doubled space is universal at least locally. We construct an
affine nondegenerate doubled bosonic AdS algebra to define the AdS space with
the Ramond-Ramond flux. The non-zero commutator of the left and right momenta
leads to that the left momentum is in an AdS space while the right momentum is
in a dS space. Dimensional reduction constraints and the physical AdS algebra
are shown to preserve all the doubled coordinates.Comment: 35 pages, v2: Explanation of the relation to other approaches, a
  pedagogical review and references are added, to appear in JHE
A small weak scale from a small cosmological constant

We propose a framework in which Weinberg's anthropic explanation of the
cosmological constant problem also solves the hierarchy problem. The weak scale
is selected by chiral dynamics that controls the stabilization of an extra
dimension. When the Higgs vacuum expectation value is close to a fermion mass
scale, the radius of an extra dimension becomes large, and develops an enhanced
number of vacua available to scan the cosmological constant down to its
observed value. At low energies, the radion necessarily appears as an
unnaturally light scalar, in a range of masses and couplings accessible to
fifth-force searches as well as scalar dark matter searches with atomic clocks
and gravitational-wave detectors. The fermion sector that controls the size of
the extra dimension consists of a pair of electroweak doublets and several
singlets. These leptons satisfy approximate mass relations related to the weak
scale and are accessible to the LHC and future colliders.Comment: 58 pages, 16 figure
Muon g-2 and related phenomenology in constrained vector-like extensions
  of the MSSM

We analyze two minimal supersymmetric constrained models with low-energy
vector-like matter preserving gauge coupling unification. In one we add to the
MSSM spectrum a pair of 5-plets of SU(5), in the other a pair of 10-plets. We
show that the muon g-2 anomaly can be explained in these models while retaining
perturbativity up to the unification scale, satisfying electroweak and flavor
precision tests and current LHC data. We examine also some related
phenomenological features of the models, including Higgs mass, fine-tuning,
dark matter and several LHC signatures. We stress that, at least for the 5-plet
model, the parameter space consistent with g-2 is entirely in reach of the LHC
with a moderate increase in luminosity with respect the current data set.Comment: 42 pages, 12 figures. Slight modifications to the text, physics
  unchanged. References added. Matches published versio
Measurements of prompt charm production cross-sections in $pp$
  collisions at $\sqrt{s} = 13\,\mathrm{TeV}$

Production cross-sections of prompt charm mesons are measured with the first
data from $pp$ collisions at the LHC at a centre-of-mass energy of
$13\,\mathrm{TeV}$. The data sample corresponds to an integrated luminosity of
$4.98 \pm 0.19\,\mathrm{pb}^{-1}$ collected by the LHCb experiment. The
production cross-sections of $D^{0}$, $D^{+}$, $D_{s}^{+}$, and $D^{*+}$ mesons
are measured in bins of charm meson transverse momentum, $p_{\mathrm{T}}$, and
rapidity, $y$, and cover the range $0 < p_{\mathrm{T}} < 15\,\mathrm{GeV}/c$
and $2.0 < y < 4.5$. The inclusive cross-sections for the four mesons,
including charge conjugation, within the range of $1 < p_{\mathrm{T}} <
8\,\mathrm{GeV}/c$ are found to be \begin{equation} \sigma(pp \to D^{0} X) =
2072 \pm 2 \pm 124\,\mu\mathrm{b}\\ \sigma(pp \to D^{+} X) = 834 \pm 2 \pm
\phantom{1}78\,\mu\mathrm{b}\\ \sigma(pp \to D_{s}^{+} X) = 353 \pm 9 \pm
\phantom{1}76\,\mu\mathrm{b}\\ \sigma(pp \to D^{*+} X) = 784 \pm 4 \pm
\phantom{1}87\,\mu\mathrm{b} \end{equation} where the uncertainties are due to
statistical and systematic uncertainties, respectively.Comment: Includes comments of erratum JHEP 09 (2016) 013 and an additional
  erratum JHEP 05 (2017) 074. All figures and tables, along with any
  supplementary material and additional information, are available at
  https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-041.htm
Expanding Einstein-Yang-Mills by Yang-Mills in CHY frame

Using the Cachazo-He-Yuan (CHY) formalism, we prove a recursive expansion of
tree level single trace Einstein-Yang-Mills (EYM) amplitudes with arbitrary
number of gluons and gravitons, which is valid for general spacetime dimensions
and any helicity configurations. The recursion is written in terms of
fewer-graviton EYM amplitudes and pure Yang-Mills (YM) amplitudes, which can be
further carried out until we reach an expansion in terms of pure YM amplitudes
in Kleiss-Kuijf (KK) basis. Our expansion then generates naturally a spanning
tree structure rooted on gluons whose vertices are gravitons. We further
propose a set of graph theoretical rules based on spanning trees that evaluate
directly the pure YM expansion coefficients.Comment: 36 pages, 3 captioned figures; v2: more details added, revised and
  published versio
$B_s\to\mu^+\mu^-$ as current and future probe of new physics

The rare flavour-changing neutral current decay $B_s\to\mu^+\mu^-$ is among
the most important indirect probes of new physics at the LHC, as it is strongly
suppressed in the Standard Model, very sensitive to new physics effects, and
theoretically exceptionally clean. We present a thorough state-of-the-art
analysis of the constraints on new physics from present and future measurements
of this decay, focusing on scalar operators. We show model-independently and in
concrete new physics models, namely the MSSM and two leptoquark scenarios, that
a future precise measurement of the mass-eigenstate rate asymmetry in
$B_s\to\mu^+\mu^-$ would allow to disentangle new physics scenarios that would
be indistinguishable based on measurements of the branching ratio alone. We
also highlight the complementarity between $B_s\to\mu^+\mu^-$ and direct
searches in both model classes. Our numerics is based on the open source code
flavio and is made publicly available.Comment: 25 pages, 8 figures. Plot scripts available at
  https://github.com/DavidMStraub/paper-bsmumu-ans. v2: numerics updated using
  published LHCb result, references added. Conclusions unchange
Cosmological evolution of Yukawa couplings: the 5D perspective

The cosmological evolution of standard model Yukawa couplings may have major
implications for baryogenesis. In particular, as highlighted recently, the CKM
matrix alone could be the source of CP-violation during electroweak
baryogenesis provided that the Yukawa couplings were large and varied during
the electroweak phase transition. We provide a natural realisation of this idea
in the context of Randall-Sundrum models and show that the geometrical warped
approach to the fermion mass hierarchy may naturally display the desired
cosmological dynamics. The key ingredient is the coupling of the
Goldberger-Wise scalar, responsible for the IR brane stabilisation, to the bulk
fermions, which modifies the fermionic profiles. This also helps alleviating
the usually tight constraints from CP-violation in Randall-Sundrum scenarios.
We study how the Yukawa couplings vary during the stabilisation of the
Randall-Sundrum geometry and can thus induce large CP-violation during the
electroweak phase transition. Using holography, we discuss the 4D
interpretation of this dynamical interplay between flavour and electroweak
symmetry breaking.Comment: 42 pages, 19 figure