pinecone/core-2020-05-10-deduplication huggingface dataset:
A rough end for smooth microstate geometries

Supersymmetric microstate geometries with five non-compact dimensions have
recently been shown by Eperon, Reall, and Santos (ERS) to exhibit a non-linear
instability featuring the growth of excitations at an "evanescent ergosurface"
of infinite redshift. We argue that this growth may be treated as adiabatic
evolution along a family of exactly supersymmetric solutions in the limit where
the excitations are Aichelburg-Sexl-like shockwaves. In the 2-charge system
such solutions may be constructed explicitly, incorporating full backreaction,
and are in fact special cases of known microstate geometries. In a near-horizon
limit, they reduce to Aichelburg-Sexl shockwaves in $AdS_3 \times S^3$
propagating along one of the angular directions of the sphere. Noting that the
ERS analysis is valid in the limit of large microstate angular momentum $j$, we
use the above identification to interpret their instability as a transition
from rare smooth microstates with large angular momentum to more typical
microstates with smaller angular momentum. This entropic driving terminates
when the angular momentum decreases to $j \sim \sqrt{n_1n_5}$ where the density
of microstates is maximal. We argue that, at this point, the large stringy
corrections to such microstates will render them non-linearly stable. We
identify a possible mechanism for this stabilization and detail an illustrative
toy model.Comment: 22 pages, 1 figure. v2: JHEP version with references adde
Higher-twist B-meson Distribution Amplitudes in HQET

We present a systematic study of higher-twist distribution amplitudes (DAs)
of the B-meson which give rise to power-suppressed $1/m_B$ contributions to
B-decays in final states with energetic light particles in the framework of QCD
factorization. As the main result, we find that the renormalization group
equations for the three-particle distributions are completely integrable in the
large $N_c$ limit and can be solved exactly. General properties of the
solutions are studied. We propose simple models for higher-twist DAs which
satify all existing constraints and can be used in phenomenological studies.Comment: 42 pages, 4 figure
Chiral trace relations in $\Omega$-deformed $\mathcal N=2$ theories

We consider $\mathcal N=2$ $SU(2)$ gauge theories in four dimensions (pure or
mass deformed) and discuss the properties of the simplest chiral observables in
the presence of a generic $\Omega$-deformation. We compute them by equivariant
localization and analyze the structure of the exact instanton corrections to
the classical chiral ring relations. We predict exact relations valid at all
instanton number among the traces $\langle\text{Tr}\varphi^{n}\rangle$, where
$\varphi$ is the scalar field in the gauge multiplet. In the
Nekrasov-Shatashvili limit, such relations may be explained in terms of the
available quantized Seiberg-Witten curves. Instead, the full two-parameter
deformation enjoys novel features and the ring relations require non trivial
additional derivative terms with respect to the modular parameter. Higher rank
groups are briefly discussed emphasizing non-factorization of correlators due
to the $\Omega$-deformation. Finally, the structure of the deformed ring
relations in the $\mathcal N=2^{\star}$ theory is analyzed from the point of
view of the Alday-Gaiotto-Tachikawa correspondence proving consistency as well
as some interesting universality properties.Comment: 36 pages. v2 references adde
Distinguishing between Dirac and Majorana neutrinos in the presence of
  general interactions

We revisit the possibility of distinguishing between Dirac and Majorana
neutrinos via neutrino-electron elastic scattering in the presence of all
possible Lorentz-invariant interactions. Defining proper observables, certain
regions of the parameter space can only be reached for Dirac neutrinos, but
never for Majorana neutrinos, thus providing an alternative method to
differentiate these two possibilities. We first derive analytically and
numerically the most general conditions that would allow to distinguish Dirac
from Majorana neutrinos, both in the relativistic and non-relativistic cases.
Then, we apply these conditions to data on $\nu_\mu$-$e$ and $\bar{\nu}_e$-$e$
scatterings, from the CHARM-II and TEXONO experiments, and find that they are
consistent with both types of neutrinos. Finally, we comment on future
prospects of this kind of tests.Comment: Comments added, version to appear in JHE
Static Gauss-Bonnet Black Holes at Large $D$

We study the static black holes in the large $D$ dimensions in the
Gauss-Bonnet gravity with a cosmological constant, coupled to the Maxewell
theory. After integrating the equation of motion with respect to the radial
direction, we obtain the effective equations at large $D$ to describe the
nonlinear dynamical deformations of the black holes. From the perturbation
analysis on the effective equations, we get the analytic expressions of the
frequencies for the quasinormal modes of charge and scalar-type perturbations.
We show that for a positive Gauss-Bonnet term, the black hole could become
unstable only if the cosmological constant is positive, otherwise the black
hole is always stable. However, for a negative Gauss-Bonnet term, we find that
the black hole could always be unstable. The instability of the black hole
depends not only on the cosmological constant and the charge, but also
significantly on the Gauss-Bonnet term. Moreover, at the onset of instability
there is a non-trivial static zero-mode perturbation, which suggests the
existence of a new non-spherically symmetric solution branch. We construct the
non-spherical symmetric static solutions of the large $D$ effective equations
explicitly.Comment: 27 pages, 34 figures. arXiv admin note: text overlap with
  arXiv:1607.0471
On the Non-Local Obstruction to Interacting Higher Spins in Flat Space

Owing to a renewed interest in flat space higher spin gauge theories, in this
note we provide further details and clarifications on the results presented in
arXiv:1107.5843 and arXiv: 1209.5755, which investigated their locality
properties. Focusing, for simplicity, on quartic amplitudes with one of the
external legs having non-zero integer spin (which can be considered as a
prototype for Weinberg-type arguments), we review the appearance of $1/\Box$
non-localities. In particular, we emphasise that it appears to be not possible
to eliminate all of the aforementioned non-localities with a judicious choice
of coupling constants and spectrum. We also discuss the light-cone gauge fixing
in $d=4$, and argue that the non-local obstruction discussed in the covariant
language cannot be avoided using light-cone gauge formalism.Comment: 22+12 pages. v2: typos corrected, references adde
A Mellin space approach to the conformal bootstrap

We describe in more detail our approach to the conformal bootstrap which uses
the Mellin representation of $CFT_d$ four point functions and expands them in
terms of crossing symmetric combinations of $AdS_{d+1}$ Witten exchange
functions. We consider arbitrary external scalar operators and set up the
conditions for consistency with the operator product expansion. Namely, we
demand cancellation of spurious powers (of the cross ratios, in position space)
which translate into spurious poles in Mellin space. We discuss two contexts in
which we can immediately apply this method by imposing the simplest set of
constraint equations. The first is the epsilon expansion. We mostly focus on
the Wilson-Fisher fixed point as studied in an epsilon expansion about $d=4$.
We reproduce Feynman diagram results for operator dimensions to $O(\epsilon^3)$
rather straightforwardly. This approach also yields new analytic predictions
for OPE coefficients to the same order which fit nicely with recent numerical
estimates for the Ising model (at $\epsilon =1$). We will also mention some
leading order results for scalar theories near three and six dimensions. The
second context is a large spin expansion, in any dimension, where we are able
to reproduce and go a bit beyond some of the results recently obtained using
the (double) light cone expansion. We also have a preliminary discussion about
numerical implementation of the above bootstrap scheme in the absence of a
small parameter.Comment: 69 pages, 4 figures, Mathematica notebook included with submissio
Higher-Spin Flat Space Cosmologies with Soft Hair

We present and discuss near horizon boundary conditions for flat space
higher-spin gravity in three dimensions. As in related work our boundary
conditions ensure regularity of the solutions independently of the charges. The
asymptotic symmetry algebra is given by a set of $\hat{\mathfrak{u}}(1)$
current algebras. The associated charges generate higher-spin soft hair. We
derive the entropy for solutions that are continuously connected to flat space
cosmologies and find the same result as in the spin-2 case: the entropy is
linear in the spin-2 zero-mode charges and independent from the spin-3 charges.
Using twisted Sugawara-like constructions of higher-spin currents we show that
our simple result for entropy of higher-spin flat space cosmologies coincides
precisely with the complicated earlier results expressed in terms of
higher-spin zero mode charges.Comment: 22 pages, A Mathematica workbook on ihs[$\lambda$] is included as an
  ancilliary file; v2: corrected minor misprints; v3: fixed minor issues with
  the display of some reference
Dynamical black holes in low-energy string theory

We investigate time-dependent spherically symmetric solutions of the
four-dimensional Einstein-Maxwell-axion-dilaton system, with the dilaton
coupling that occurs in low-energy effective heterotic string theory. A class
of dilaton-electrovacuum radiating solutions with a trivial axion, previously
found by G\"uven and Y\"or\"uk, is re-derived in a simpler manner and its
causal structure is clarified. It is shown that such dynamical spacetimes
featuring apparent horizons do not possess a regular light-like past null
infinity or future null infinity, depending on whether they are radiating or
accreting. These solutions are then extended in two ways. First we consider a
Vaidya-like generalisation, which introduces a null dust source. Such
spacetimes are used to test the status of cosmic censorship in the context of
low-energy string theory. We prove that - within this family of solutions -
regular black holes cannot evolve into naked singularities by accreting null
dust, unless standard energy conditions are violated. Secondly, we employ
S-duality to derive new time-dependent dyon solutions with a nontrivial axion
turned on. Although they share the same causal structure as their
Einstein-Maxwell-dilaton counterparts, these solutions possess both electric
and magnetic charges.Comment: 1+24 pages + appendices, 6 figures; v2: minor corrections, added
  reference, matches published versio
The R*-operation for Feynman graphs with generic numerators

The R*-operation by Chetyrkin, Tkachov, and Smirnov is a generalisation of
the BPHZ R-operation, which subtracts both ultraviolet and infrared divergences
of euclidean Feynman graphs with non-exceptional external momenta. It can be
used to compute the divergent parts of such Feynman graphs from products of
simpler Feynman graphs of lower loops. In this paper we extend the R*-operation
to Feynman graphs with arbitrary numerators, including tensors. We also provide
a novel way of defining infrared counterterms which closely resembles the
definition of its ultraviolet counterpart. We further express both infrared and
ultraviolet counterterms in terms of scaleless vacuum graphs with a logarithmic
degree of divergence. By exploiting symmetries, integrand and integral
relations, which the counterterms of scaleless vacuum graphs satisfy, we can
vastly reduce their number and complexity. A FORM implementation of this method
was used to compute the five loop beta function in QCD for a general gauge
group. To illustrate the procedure, we compute the poles in the dimensional
regulator of all top-level propagator graphs at five loops in four dimensional
phi^3 theory.Comment: 38 pages, lots of graphs; minor typos corrected and references adde
Cosmological Signals of a Mirror Twin Higgs

We investigate the cosmology of the minimal model of neutral naturalness, the
mirror Twin Higgs. The softly-broken mirror symmetry relating the Standard
Model to its twin counterpart leads to significant dark radiation in tension
with BBN and CMB observations. We quantify this tension and illustrate how it
can be mitigated in several simple scenarios that alter the relative energy
densities of the two sectors while respecting the softly-broken mirror
symmetry. In particular, we consider both the out-of-equilibrium decay of a new
scalar as well as reheating in a toy model of twinned inflation, Twinflation.
In both cases the dilution of energy density in the twin sector does not merely
reconcile the existence of a mirror Twin Higgs with cosmological constraints,
but predicts contributions to cosmological observables that may be probed in
current and future CMB experiments. This raises the prospect of discovering
evidence of neutral naturalness through cosmology rather than colliders.Comment: 44 pages, 12 figures, v2 updated to match published versio
Some exact Bradlow vortex solutions

We consider the Bradlow equation for vortices which was recently found by
Manton and find a two-parameter class of analytic solutions in closed form on
nontrivial geometries with non-constant curvature. The general solution to our
class of metrics is given by a hypergeometric function and the area of the
vortex domain by the Gaussian hypergeometric function.Comment: LaTeX: 16 pages, no figures; V2: references added, minor additions;
  V3 (published version): toy model added as section 3 and conjecture 1 added
  in section 4.
Grassmannian Integral for General Gauge Invariant Off-shell Amplitudes
  in N=4 SYM

In this paper we consider tree-level gauge invariant off-shell amplitudes
(Wilson line form factors) in $\mathcal{N}=4$ SYM with arbitrary number of
off-shell gluons or equivalently Wilson line operator insertions. We make a
conjecture for the Grassmannian integral representation for such objects and
verify our conjecture on several examples. It is remarkable that in our
formulation one can consider situation when on-shell particles are not present
at all, i.e. we have Grassmannian integral representation for purely off-shell
object. In addition we show that off-shell amplitude with arbitrary number of
off-shell gluons could be also obtained using quantum inverse scattering method
for auxiliary $\mathfrak{gl}(4|4)$ super spin chain.Comment: 38 pages, 9 figures; v4: typos corrected, comment in section 3.2
  adde
Notes on Spinning Operators in Fermionic CFT

The Gross-Neveu model defines a unitary CFT of interacting fermions in
$2<d<4$ which has perturbative descriptions in the $1/N$ expansion and in the
epsilon-expansion near two and four dimensions. In each of these descriptions,
the CFT has an infinite tower of nearly conserved currents of all spins. We
determine the structure of the non-conservation equations both at large $N$ and
in the epsilon-expansion, and use it to find the leading order anomalous
dimensions of the broken currents. Similarly, we use the fact that the CFT
spectrum includes a nearly free fermion to fix the leading anomalous dimensions
of a few scalar composite operators. We also compute the scaling dimensions of
double-trace spinning operators in the large $N$ expansion, which correspond to
interaction energies of two-particle states in the AdS dual higher-spin theory.
We first derive these anomalous dimensions by a direct Feynman diagram
calculation, and then show that the result can be exactly reproduced by
analytic bootstrap methods, provided the sum over the tower of weakly broken
higher-spin currents is suitably regularized. Finally, we apply the analytic
bootstrap approach to derive the anomalous dimensions of the double-trace
spinning operators in the 3d bosonic and fermion vector models coupled to
Chern-Simons theory, to leading order in $1/N$ but exactly in the `t Hooft
coupling.Comment: 37 pages, 1 figure. v2: minor correction
Permutations of Massive Vacua

We discuss the permutation group G of massive vacua of four-dimensional gauge
theories with N=1 supersymmetry that arises upon tracing loops in the space of
couplings. We concentrate on superconformal N=4 and N=2 theories with N=1
supersymmetry preserving mass deformations. The permutation group G of massive
vacua is the Galois group of characteristic polynomials for the vacuum
expectation values of chiral observables. We provide various techniques to
effectively compute characteristic polynomials in given theories, and we deduce
the existence of varying symmetry breaking patterns of the duality group
depending on the gauge algebra and matter content of the theory. Our examples
give rise to interesting field extensions of spaces of modular forms.Comment: 44 pages, 1 figur
An Effective Two-Flavor Approximation for Neutrino Survival
  Probabilities in Matter

It is known in vacuum that the three-flavor neutrino survival probability can
be approximated by the effective two-flavor form to first orders in $\epsilon
\equiv \Delta m^2_{21} / \Delta m^2_{31}$, with introduction of the effective
$\Delta m^2_{\alpha \alpha}$ ($\alpha = e, \mu, \tau$), in regions of neutrino
energy $E$ and baseline $L$ such that $\Delta m^2_{31} L / 2E \sim \pi$. Here,
we investigate the question of whether the similar effective two-flavor
approximation can be formulated for the survival probability in matter. Using a
perturbative framework with the expansion parameters $\epsilon$ and $s_{13}
\propto \sqrt{\epsilon}$, we give an affirmative answer to this question and
the resultant two-flavor form of the probability is valid to order $\epsilon$.
However, we observe a contrived feature of the effective $\Delta m^2_{\alpha
\alpha} (a)$ in matter. It ceases to be a combination of the fundamental
parameters and has energy dependence, which may be legitimate because it comes
from the matter potential. But, it turned out that $\Delta m^2_{\mu \mu} (a)$
becomes $L$-dependent, though $\Delta m^2_{ee} (a)$ is not, which casts doubt
on adequacy of the concept of effective $\Delta m^2$ in matter. We also find
that the appearance probability in vacuum admits, to order $\epsilon$, the
similar effective two-flavor form with a slightly different effective $\Delta
m^2_{\beta \alpha}$ from the disappearance channel. A general result is derived
to describe suppression of the matter effect in the oscillation probability.Comment: Discussion on appearance effective $\Delta m^2$ added. Version to
  appear in JHEP. 26 pages, 3 figure
Complex Langevin dynamics and zeroes of the fermion determinant

QCD at nonzero baryon chemical potential suffers from the sign problem, due
to the complex quark determinant. Complex Langevin dynamics can provide a
solution, provided certain conditions are met. One of these conditions,
holomorphicity of the Langevin drift, is absent in QCD since zeroes of the
determinant result in a meromorphic drift. We first derive how poles in the
drift affect the formal justification of the approach and then explore the
various possibilities in simple models. The lessons from these are subsequently
applied to both heavy dense QCD and full QCD, and we find that the results
obtained show a consistent picture. We conclude that with careful monitoring,
the method can be justified a posteriori, even in the presence of
meromorphicity.Comment: 67 pages, many figures; minor changes, discussion section added, to
  appear in JHE
Hairy black holes in cubic quasi-topological gravity

We construct a class of five dimensional black hole solutions to cubic
quasi-topological gravity with conformal scalar hair and study their
thermodynamics. We find these black holes provide the second example of black
hole $\lambda$-lines: a line of second order (continuous) phase transitions,
akin to the fluid/superfluid transition of $^4$He. Examples of isolated
critical points are found for spherical black holes, marking the first in the
literature to date. We also find various novel and interesting phase
structures, including an isolated critical point occurring in conjunction with
a double reentrant phase transition. The AdS vacua of the theory are studied,
finding ghost-free configurations where the scalar field takes on a non-zero
constant value, in notable contrast to the five dimensional Lovelock case.Comment: 29 pages, 12 figure
Non-toric Cones and Chern-Simons Quivers

We obtain an integral formula for the volume of non-toric tri-Sasaki Einstein
manifolds arising from nonabelian hyperkahler quotients. The derivation is
based on equivariant localization and generalizes existing formulas for Abelian
quotients, which lead to toric manifolds. The formula is particularly valuable
in the context of AdS$_{4}\times Y_{7}$ vacua of M-theory and their field
theory duals. As an application, we consider 3d $\mathcal N=3$ Chern-Simons
theories with affine ADE quivers. While the $\widehat A$ series corresponds to
toric $Y_{7}$, the $\widehat D$ and $\widehat E$ series are non-toric. We
compute the volumes of the corresponding seven-manifolds and compare to the
prediction from supersymmetric localization in field theory, finding perfect
agreement. This is the first test of an infinite number of non-toric
AdS$_4$/CFT$_3$ dualities.Comment: 2+24 pages. v2: Minor improvements to the text. Matches published
  versio
No More Walls! A Tale of Modularity, Symmetry, and Wall Crossing for 1/4
  BPS Dyons

We determine the generating functions of 1/4 BPS dyons in a class of 4d
$\mathcal{N}=4$ string vacua arising as CHL orbifolds of $K3 \times T^2$, a
classification of which has been recently completed. We show that all such
generating functions obey some simple physical consistency conditions that are
very often sufficient to fix them uniquely. The main constraint we impose is
the absence of unphysical walls of marginal stability: discontinuities of 1/4
BPS degeneracies can only occur when 1/4 BPS dyons decay into pairs of 1/2 BPS
states. Formally, these generating functions in spacetime can be described as
multiplicative lifts of certain supersymmetric indices (twining genera) on the
worldsheet of the corresponding nonlinear sigma model on K3. As a consequence,
our procedure also leads to an explicit derivation of almost all of these
twining genera. The worldsheet indices singled out in this way match precisely
a set of functions of interest in moonshine, as predicted by a recent
conjecture.Comment: 55 + 22 page
On instanton effects in the operator product expansion

We revisit the computation of instanton effects to various correlation
functions in ${\cal N}=4$ SYM and clarify a controversy existing in the
literature regarding their consistency with the OPE and conformal symmetry. To
check these properties, we examine the conformal partial wave decomposition of
four-point correlators involving combinations of half-BPS and Konishi operators
and isolate the contribution from the conformal primary scalar operators of
twist four. We demonstrate that the leading instanton correction to this
contribution is indeed consistent with conformal symmetry and compute the
corresponding corrections to the OPE coefficients and the scaling dimensions of
such twist-four operators. Our analysis justifies the regularization procedure
used to compute ultraviolet divergent instanton contribution to correlation
functions involving unprotected operators.Comment: 22 pages,v2: minor correction