pinecone/core-2020-05-10-deduplication huggingface dataset:
Exact Bremsstrahlung and Effective Couplings

We calculate supersymmetric Wilson loops on the ellipsoid for a large class
of $\mathcal{N}=2$ SCFT using the localization formula of Hama and Hosomichi.
From them we extract the radiation emitted by an accelerating heavy probe quark
as well as the entanglement entropy following the recent works of
Lewkowycz-Maldacena and Fiol-Gerchkovitz-Komargodski. Comparing our results
with the $\mathcal{N}=4$ SYM ones, we obtain interpolating functions $f(g^2)$
such that a given $\mathcal{N}=2$ SCFT observable is obtained by replacing in
the corresponding $\mathcal{N}=4$ SYM result the coupling constant by $f(g^2)$.
These "exact effective couplings" encode the finite, relative renormalization
between the $\mathcal{N}=2$ and the $\mathcal{N}=4$ gluon propagator, they
interpolate between the weak and the strong coupling. We discuss the range of
their applicability.Comment: 16 pages, 10 pages appendices, 4 figures. v2, journal versio
$C_T$ for Non-unitary CFTs in Higher Dimensions

The coefficient $C_T$ of the conformal energy-momentum tensor two-point
function is determined for the non-unitary scalar CFTs with four- and
six-derivative kinetic terms. The results match those expected from large-$N$
calculations for the CFTs arising from the $O(N)$ non-linear sigma and
Gross-Neveu models in specific even dimensions. $C_T$ is also calculated for
the CFT arising from $(n-1)$-form gauge fields with derivatives in $2n+2$
dimensions. Results for $(n-1)$-form theory extended to general dimensions as a
non-gauge-invariant CFT are also obtained; the resulting $C_T$ differs from
that for the gauge-invariant theory. The construction of conformal primaries by
subtracting descendants of lower-dimension primaries is also discussed. For
free theories this also leads to an alternative construction of the
energy-momentum tensor, which can be quite involved for higher-derivative
theories.Comment: 19 pages. v2: References added, discussion expanded, typos fixed. v3:
  Note added including a derivation of eq. (2.13). v4: Minor clarifications,
  version to appear in JHE
Signs of Composite Higgs Pair Production at Next-to-Leading Order

In composite Higgs models the Higgs boson arises as a pseudo-Goldstone boson
from a strongly-interacting sector. Fermion mass generation is possible through
partial compositeness accompanied by the appearance of new heavy fermionic
resonances. The Higgs couplings to the Standard Model (SM) particles and
between the Higgs bosons themselves are modified with respect to the SM. Higgs
pair production is sensitive to the trilinear Higgs self-coupling but also to
anomalous couplings like the novel 2-Higgs-2-fermion coupling emerging in
composite Higgs models. The QCD corrections to SM Higgs boson pair production
are known to be large. In this paper we compute, in the limit of heavy loop
particle masses, the next-to-leading order (NLO) QCD corrections to Higgs pair
production in composite Higgs models without and with new heavy fermions. The
relative QCD corrections are found to be almost insensitive both to the
compositeness of the Higgs boson and to the details of the heavy fermion
spectrum, since the leading order cross section dominantly factorizes. With the
obtained results we investigate the question if, taking into account Higgs
coupling constraints, new physics could first be seen in Higgs pair production.
We find this to be the case in the high-luminosity option of the LHC for
composite Higgs models with heavy fermions. We also investigate the invariant
mass distributions at NLO QCD. While they are sensitive to the Higgs
non-linearities and hence anomalous couplings, the influence of the heavy
fermions is much less pronounced
Experimental Considerations Motivated by the Diphoton Excess at the LHC

We consider the immediate or near-term experimental opportunities offered by
some scenarios that could explain the new diphoton excess at the LHC. If the
excess is due to a new particle $X_s$ at 750 GeV, additional new particles are
required, providing further signals. If connected with naturalness, the $X_s$
may be produced in top partner decays. Then a $t'\bar t'$ signal, with $t'\to t
X_s$ and $X_s\to gg$ dominantly, might be discovered by reinterpreting 13 TeV
SUSY searches in multijet events with low MET and/or a lepton. If $X_s$ is a
bound state of quirks, the signal events may be accompanied by an unusual
number of soft tracks or soft jets. Other resonances including dilepton and
photon+jet as well as dijet may lie at or above this mass, and signatures of
hidden glueballs might also be observable. If the "photons" in the excess are
actually long-lived particles decaying to photon pairs or to electron pairs,
there are opportunities for detecting overlapping photons and/or unusual
patterns of apparent photon-conversions in either $X_s$ or 125 GeV Higgs
decays. There is also the possibility of events with a hard "photon" recoiling
against a narrow isolated HCAL-only "jet", which, after the jet's energy is
corrected for its electromagnetic origin, would show a peak at 750 GeV.Comment: Version 2: References added, updated range for target cross section,
  modified perturbativity limit for vectorlike fermions, updated benchmark for
  resonance decaying to axions, figure 4 modified. Other minor changes,
  conclusions unchange
Linear flavour violation and anomalies in B physics

We propose renormalizable models of new physics that can explain various
anomalies observed in decays of B-mesons to electron and muon pairs. The new
physics states couple to linear combinations of Standard Model fermions,
yielding a pattern of flavour violation that gives a consistent fit to the
gamut of flavour data. Accidental symmetries prevent contributions to baryon-
and lepton-number-violating processes, as well as enforcing a loop suppression
of new physics contributions to flavour violating processes. Data require that
the new flavour-breaking couplings are largely aligned with the Yukawa
couplings of the SM and so we also explore patterns of flavour symmetry
breaking giving rise to this structure.Comment: v2: 28 pages, 10 figures. Added two appendices to make the SU(2)
  structure of the model clearer, and to discuss Z/photon penguin
  contributions. Updated a bound on Bs mixing, and added references.
  Conclusions unchanged. Version to appear in JHE
Entanglement entropy from one-point functions in holographic states

For holographic CFT states near the vacuum, entanglement entropies for
spatial subsystems can be expressed perturbatively as an expansion in the
one-point functions of local operators dual to light bulk fields. Using the
connection between quantum Fisher information for CFT states and canonical
energy for the dual spacetimes, we describe a general formula for this
expansion up to second-order in the one-point functions, for an arbitrary
ball-shaped region, extending the first-order result given by the entanglement
first law. For two-dimensional CFTs, we use this to derive a completely
explicit formula for the second-order contribution to the entanglement entropy
from the stress tensor. We show that this stress tensor formula can be
reproduced by a direct CFT calculation for states related to the vacuum by a
local conformal transformation. This result can also be reproduced via the
perturbative solution to a non-linear scalar wave equation on an auxiliary de
Sitter spacetime, extending the first-order result in arXiv/1509.00113.Comment: 34 pages, 2 figures; v2 references added, minor typos correcte
Gravitational Black Hole Hair from Event Horizon Supertranslations

We discuss BMS supertranslations both at null-infinity and on the horizon for
the case of the Schwarzschild black hole. We show that both kinds of
supertranslations lead to infinetly many gapless physical excitations. On this
basis we construct a quotient algebra using suited superpositions of both kinds
of transformations which cannot be compensated by an ordinary
BMS-supertranslation and therefore are intrinsically due to the presence of an
event horizon. We show that these quotient transformations are physical and
generate gapless excitations on the horizon that can account for the
gravitational hair as well as for the black hole entropy. We identify the
physics of these modes as associated with Bogolioubov-Goldstone modes due to
quantum criticality. Classically the number of these gapless modes is infinite.
However, we show that due to quantum criticality the actual amount of
information-carriers becomes finite and consistent with Bekenstein entropy.
Although we only consider the case of Schwarzschild geometry, the arguments are
extendable to arbitrary space-times containing event horizons.Comment: 29 pages, Late
Witten Index for Noncompact Dynamics

Among gauged dynamics motivated by string theory, we find many with gapless
asymptotic directions. Although the natural boundary condition for ground
states is $L^2$, one often turns on chemical potentials or supersymmetric mass
terms to regulate the infrared issues, instead, and computes the twisted
partition function. We point out how this procedure generically fails to
capture physical $L^2$ Witten index with often misleading results. We also
explore how, nevertheless, the Witten index is sometimes intricately embedded
in such twisted partition functions. For $d=1$ theories with gapless continuum
sector from gauge multiplets, such as non-primitive quivers and pure
Yang-Mills, a further subtlety exists, leading to fractional expressions. Quite
unexpectedly, however, the integral $L^2$ Witten index can be extracted
directly and easily from the twisted partition function of such theories. This
phenomenon is tied to the notion of the rational invariant that appears
naturally in the wall-crossing formulae, and offers a general mechanism of
reading off Witten index directly from the twisted partition function. Along
the way, we correct early numerical results for some of $\mathcal N=4,8,16$
pure Yang-Mills quantum mechanics, and count threshold bound states for general
gauge groups beyond $SU(N)$.Comment: 54 pages, JHEP version, references updated with accompanying
  footnotes, an additional example added in Eq.(5.22
Conformal Bootstrap With Slightly Broken Higher Spin Symmetry

We consider conformal field theories with slightly broken higher spin
symmetry in arbitrary spacetime dimensions. We analyze the crossing equation in
the double light-cone limit and solve for the anomalous dimensions of higher
spin currents $\gamma_s$ with large spin $s$. The result depends on the
symmetries and the spectrum of the unperturbed conformal field theory. We
reproduce all known results and make further predictions. In particular we make
a prediction for the anomalous dimensions of higher spin currents in the 3d
Ising model.Comment: 41 pages, 2 figures, %\draftmod
Global analysis of $b\to s\ell\ell$ anomalies

We present a detailed discussion of the current theoretical and experimental
situation of the anomaly in the angular distribution of $B \to K^*(\to
K\pi)\mu^+\mu^-$, observed at LHCb in the $1~\text{fb}^{-1}$ dataset and
recently confirmed by the $3~\text{fb}^{-1}$ dataset. The impact of this data
and other recent measurements on $b\to s\ell^+\ell^-$ transitions
($\ell=e,\mu$) is considered. We review the observables of interest, focusing
on their theoretical uncertainties and their sensitivity to New Physics, based
on an analysis employing the QCD factorisation approach including several
sources of hadronic uncertainties (form factors, power corrections, charm-loop
effects). We perform fits to New Physics contributions including experimental
and theoretical correlations. The solution that we proposed in 2013 to solve
the $B\to K^*\mu^+\mu^-$ anomaly, with a contribution ${\mathcal C}_9^{\rm
NP}\simeq -1$, is confirmed and reinforced. A wider range of New-Physics
scenarios with high significances (between 4 and 5 $\sigma$) emerges from the
fit, some of them being particularly relevant for model building. More data is
needed to discriminate among them conclusively. The inclusion of $b\to s e^+
e^-$ observables increases the significance of the favoured scenarios under the
hypothesis of New Physics breaking lepton flavour universality. Several tests
illustrate the robustness of our conclusions.Comment: 54 pages + appendices, plenty of figures. Minor corrections,
  references added, version published in JHE
Elliptic scattering equations

Recently the CHY approach has been extended to one loop level using elliptic
functions and modular forms over a Jacobian variety. Due to the difficulty in
manipulating these kind of functions, we propose an alternative prescription
that is totally algebraic. This new proposal is based on an elliptic algebraic
curve embedded in a $\mathbb{C}P^2$ space. We show that for the simplest
integrand, namely the ${\rm n-gon}$, our proposal indeed reproduces the
expected result. By using the recently formulated $\Lambda-$algorithm, we found
a novel recurrence relation expansion in terms of tree level off-shell
amplitudes. Our results connect nicely with recent results on the one-loop
formulation of the scattering equations. In addition, this new proposal can be
easily stretched out to hyperelliptic curves in order to compute higher genus.Comment: v3: Typ
Spectral sum rules for confining large-N theories

We consider asymptotically-free four-dimensional large-$N$ gauge theories
with massive fermionic and bosonic adjoint matter fields, compactified on
squashed three-spheres, and examine their regularized large-$N$ confined-phase
spectral sums. The analysis is done in the limit of vanishing 't Hooft
coupling, which is justified by taking the size of the compactification
manifold to be small compared to the inverse strong scale $\Lambda^{-1}$. Our
results motivate us to conjecture some universal spectral sum rules for these
large $N$ gauge theories.Comment: 25 pages, 2 figures. v2: fixed typos, added references, and some
  minor improvements to discussio
Hairy Black Holes in AdS$_5\times S^5$

We use numerical methods to exhaustively study a novel family of hairy black
hole solutions in AdS$_5$. These solutions can be uplifted to solutions of type
IIB supergravity with AdS$_5\times S^5$ asymptotics and are thus expected to
play an important role in our understanding of AdS/CFT. We find an intricate
phase diagram, with the aforementioned family of hairy black hole solutions
branching from the Reissner-Nordstr\"om black hole at the onset of the
superradiance instability. We analyse black holes with spherical and planar
horizon topology and explain how they connect in the phase diagram. Finally, we
detail their global and local thermodynamic stability across several ensembles.Comment: 27 pages, 40 figure
Chern-Simons Actions and Their Gaugings in 4D, N=1 Superspace

We gauge the abelian hierarchy of tensor fields in 4D by a Lie algebra. The
resulting non-abelian tensor hierarchy can be interpreted via an equivariant
chain complex. We lift this structure to N=1 superspace by constructing
superfield analogs for the tensor fields, along with covariant superfield
strengths. Next we construct Chern-Simons actions, for both the bosonic and N=1
cases, and note that the condition of gauge invariance can be presented
cohomologically. Finally, we provide an explicit realization of these
structures by dimensional reduction, for example by reducing the three-form of
eleven-dimensional supergravity into a superspace with manifest 4D, N=1
supersymmetry.Comment: 40pp, v2 added reference
Evidence for a Nonplanar Amplituhedron

The scattering amplitudes of planar N = 4 super-Yang-Mills exhibit a number
of remarkable analytic structures, including dual conformal symmetry and
logarithmic singularities of integrands. The amplituhedron is a geometric
construction of the integrand that incorporates these structures. This
geometric construction further implies the amplitude is fully specified by
constraining it to vanish on spurious residues. By writing the amplitude in a
dlog basis, we provide nontrivial evidence that these analytic properties and
"zero conditions" carry over into the nonplanar sector. This suggests that the
concept of the amplituhedron can be extended to the the nonplanar sector of N =
4 super-Yang-Mills theory.Comment: 44 pages, 9 figure
Entanglement Entropy of the N=4 SYM spin chain

We present a detailed study of the Entanglement Entropy (EE) of excited
states in all closed rank one subsectors of N=4 SYM, namely SU(2), SU(1|1) and
SL(2). Exploiting the techniques of the Coordinate and the Algebraic Bethe
Ansatz we obtain the EE for spin chains with up to seven magnons, at leading
order in the coupling expansion but exact in the length of the spin chain and
of the part of it that we cut. Focusing on the superconformal primary operator
with two magnons in the BMN limit, we derive analytic and exact, in the
coupling $\lambda'$, expressions for the Renyi and the EE. The interpolating
functions for the Renyi and the EE monotonically increase as the coupling
increases from the weak coupling $\lambda' \rightarrow 0$ regime to the strong
coupling $\lambda' \rightarrow \infty$ regime. This results to a violation of a
certain bound for the EE that is present at weak coupling and confirms the
physical intuition that entanglement increases when the coupling increases.Comment: 33 pages, 12 figures; v2: Typos corrected and a new appendix with the
  Bethe roots added; JHEP published versio
Genuine T, CP, CPT asymmetry parameters for the entangled
  $\boldsymbol{B_d}$ system

The precise connection between the theoretical T, CP, CPT asymmetries, in
terms of transition probabilities between the filtered neutral meson $B_d$
states and the experimental asymmetries between the double decay rate
intensities for Flavour-CP eigenstate decay products in a B-factory of
entangled states, is established. This allows the identification of genuine
Asymmetry Parameters in the time distribution of the asymmetries and their
measurability by disentangling genuine and possible fake terms. We express the
nine asymmetry parameters -- three different observables for each one of the
three symmetries -- in terms of the ingredients of the Weisskopf-Wigner
dynamical description of the entangled $B_d$-meson states and we obtain a
global fit to their values from the BaBar collaboration experimental results.
The possible fake terms are all compatible with zero and the information
content of the nine asymmetry parameters is indeed different. The non-vanishing
$\Delta\mathscr S_c^{\rm T} =-0.687\pm 0.020 $ and $\Delta\mathscr S_c^{\rm
CP}=-0.680\pm 0.021$ are impressive separate direct evidence of
Time-Reversal-violation and CP-violation in these transitions and compatible
with Standard Model expectations. An intriguing 2$\sigma$ effect for the
Re($\theta$) parameter responsible of CPT-Violation appears which, interpreted
as an upper limit, leads to $|M_{\bar B^0\bar B^0}-M_{B^0B^0}| < 4.0\times
10^{-5}$ eV at 95\% C.L. for the diagonal flavour terms of the mass matrix. It
contributes to the CP-violating $\Delta\mathscr C_c^{\rm CP}$ asymmetry
parameter in an unorthodox manner -- in its $\cos(\Delta M\,t)$ time dependence
--, and it is accessible in facilities with non-entangled $B_d$'s, like the
LHCb experiment.Comment: 26 pages, 5 figures; minor changes, matches published versio
$\Lambda$ Scattering Equations

The CHY representation of scattering amplitudes is based on integrals over
the moduli space of a punctured sphere. We replace the punctured sphere by a
double-cover version. The resulting scattering equations depend on a parameter
$\Lambda$ controlling the opening of a branch cut. The new representation of
scattering amplitudes possesses an enhanced redundancy which can be used to
fix, modulo branches, the location of four punctures while promoting $\Lambda$
to a variable. Via residue theorems we show how CHY formulas break up into sums
of products of smaller (off-shell) ones times a propagator. This leads to a
powerful way of evaluating CHY integrals of generic rational functions, which
we call the $\Lambda$ algorithm.Comment: v3: ref added, minor typos fixe
Massless sunset diagrams in finite asymmetric volumes

This paper discusses the methods and the results used in an accompanying
paper describing the matching of effective chiral Lagrangians in dimensional
and lattice regularizations. We present methods to compute 2-loop massless
sunset diagrams in finite asymmetric volumes in the framework of these
regularizations. We also consider 1-loop sums in both regularizations,
extending the results of Hasenfratz and Leutwyler for the case of dimensional
regularization and we introduce a new method to calculate precisely the
expansion coefficients of the 1-loop lattice sums.Comment: published version, 57 pages, no figure
Boundary conditions for General Relativity on AdS$_{3}$ and the KdV
  hierarchy

It is shown that General Relativity with negative cosmological constant in
three spacetime dimensions admits a new family of boundary conditions being
labeled by a nonnegative integer $k$. Gravitational excitations are then
described by "boundary gravitons" that fulfill the equations of the $k$-th
element of the KdV hierarchy. In particular, $k=0$ corresponds to the
Brown-Henneaux boundary conditions so that excitations are described by chiral
movers. In the case of $k=1$, the boundary gravitons fulfill the KdV equation
and the asymptotic symmetry algebra turns out to be infinite-dimensional,
abelian and devoid of central extensions. The latter feature also holds for the
remaining cases that describe the hierarchy ($k>1$). Our boundary conditions
then provide a gravitational dual of two noninteracting left and right KdV
movers, and hence, boundary gravitons possess anisotropic Lifshitz scaling with
dynamical exponent $z=2k+1$. Remarkably, despite spacetimes solving the field
equations are locally AdS, they possess anisotropic scaling being induced by
the choice of boundary conditions. As an application, the entropy of a rotating
BTZ black hole is precisely recovered from a suitable generalization of the
Cardy formula that is compatible with the anisotropic scaling of the chiral KdV
movers at the boundary, in which the energy of AdS spacetime with our boundary
conditions depends on $z$ and plays the role of the central charge. The
extension of our boundary conditions to the case of higher spin gravity and its
link with different classes of integrable systems is also briefly addressed.Comment: 18 pages, no figures, Final version for JHE
Cosmological and Astrophysical Probes of Vacuum Energy

Vacuum energy changes during cosmological phase transitions and becomes
relatively important at epochs just before phase transitions. For a viable
cosmology the vacuum energy just after a phase transition must be set by the
critical temperature of the next phase transition, which exposes the
cosmological constant problem from a different angle. Here we propose to
experimentally test the properties of vacuum energy under circumstances
different from our current vacuum. One promising avenue is to consider the
effect of high density phases of QCD in neutron stars. Such phases have
different vacuum expectation values and a different vacuum energy from the
normal phase, which can contribute an order one fraction to the mass of neutron
stars. Precise observations of the mass of neutron stars can potentially yield
information about the gravitational properties of vacuum energy, which can
significantly affect their mass-radius relation. A more direct test of cosmic
evolution of vacuum energy could be inferred from a precise observation of the
primordial gravitational wave spectrum at frequencies corresponding to phase
transitions. While traditional cosmology predicts steps in the spectrum
determined by the number of degrees of freedom both for the QCD and electroweak
phase transitions, an adjustment mechanism for vacuum energy could
significantly change this. In addition, there might be other phase transitions
where the effect of vacuum energy could show up as a peak in the spectrum.Comment: 28 pages, LaTeX, 7 figure