pinecone/core-2020-05-10-deduplication huggingface dataset:
Holographic renormalization and supersymmetry

Holographic renormalization is a systematic procedure for regulating
divergences in observables in asymptotically locally AdS spacetimes. For dual
boundary field theories which are supersymmetric it is natural to ask whether
this defines a supersymmetric renormalization scheme. Recent results in
localization have brought this question into sharp focus: rigid supersymmetry
on a curved boundary requires specific geometric structures, and general
arguments imply that BPS observables, such as the partition function, are
invariant under certain deformations of these structures. One can then ask if
the dual holographic observables are similarly invariant. We study this
question in minimal N = 2 gauged supergravity in four and five dimensions. In
four dimensions we show that holographic renormalization precisely reproduces
the expected field theory results. In five dimensions we find that no choice of
standard holographic counterterms is compatible with supersymmetry, which leads
us to introduce novel finite boundary terms. For a class of solutions
satisfying certain topological assumptions we provide some independent tests of
these new boundary terms, in particular showing that they reproduce the
expected VEVs of conserved charges.Comment: 70 pages; corrected typo
QCD Factorization for $B \to \pi\pi\ell\nu$ Decays at Large Dipion
  Masses

We introduce a factorization formula for semi-leptonic $b \to u$ transitions
in the exclusive decay mode $B^- \to \pi^+\pi^-\ell^-\bar\nu_\ell$ in the limit
of large pion energies and large dipion invariant mass. One contribution can be
described in terms of a universal $B \to \pi$ form factor and the convolution
of a short-distance kernel $T^{\rm I}$ with the respective light-cone
distribution amplitudes (LCDAs) of the positively charged pion. The second
contribution, at leading power, completely factorizes, with a short-distance
kernel $T^{\rm II}$ convoluted with the leading-twist LCDAs for both pions and
the $B$-meson. We calculate the leading contributions to the short-distance
kernels $T^{\rm I}$ and $T^{\rm II}$ in fixed-order perturbation theory, and
discuss the approximate relations among the resulting $B \to \pi\pi$
partial-wave form factors. Our results provide useful theoretical constraints
for phenomenological models that aim to analyze the complete $B \to \pi\pi
\ell\nu$ phase space.Comment: 38 pages, 5 figures; v2: as published, conclusions unchange
Superluminality, Black Holes and Effective Field Theory

Under the assumption that a UV theory does not display superluminal behavior,
we ask what constraints on superluminality are satisfied in the effective field
theory (EFT). We study two examples of effective theories: quantum
electrodynamics (QED) coupled to gravity after the electron is integrated out,
and the flat-space galileon. The first is realized in nature, the second is
more speculative, but they both exhibit apparent superluminality around
non-trivial backgrounds. In the QED case, we attempt, and fail, to find
backgrounds for which the superluminal signal advance can be made larger than
the putative resolving power of the EFT. In contrast, in the galileon case it
is easy to find such backgrounds, indicating that if the UV completion of the
galileon is (sub)luminal, quantum corrections must become important at distance
scales of order the Vainshtein radius of the background configuration, much
larger than the naive EFT strong coupling distance scale. Such corrections
would be reminiscent of the non-perturbative Schwarzschild scale quantum
effects that are expected to resolve the black hole information problem.
Finally, a byproduct of our analysis is a calculation of how perturbative
quantum effects alter charged Reissner-Nordstrom black holes.Comment: 51 pages, many figures. v2 typo fixed, refs adde
Yukawa Sector of Minimal SO(10) Unification

We show that in SO(10) models, a Yukawa sector consisting of a real $10_H$, a
real $120_H$ and a complex $126_H$ of Higgs fields can provide a realistic fit
to all fermion masses and mixings, including the neutrino sector. Although the
group theory of SO(10) demands that the $10_H$ and $120_H$ be real, most
constructions complexify these fields and impose symmetries exterior to SO(10)
to achieve predictivity. The proposed new framework with real $10_H$ and real
$120_H$ relies only on SO(10) gauge symmetry, and yet has a limited number of
Yukawa parameters. Our analysis shows that while there are restrictions on the
observables, a good fit to the entire fermion spectrum can be realized.
Unification of gauge couplings is achieved with an intermediate scale
Pati-Salam gauge symmetry. Proton decay branching ratios are calculable, with
the leading decay modes being $p \rightarrow \overline{\nu} \pi^+$ and $p
\rightarrow e^+ \pi^0$.Comment: 24 pages, LaTeX, 2 figure
Heptagons from the Steinmann Cluster Bootstrap

We reformulate the heptagon cluster bootstrap to take advantage of the
Steinmann relations, which require certain double discontinuities of any
amplitude to vanish. These constraints vastly reduce the number of functions
needed to bootstrap seven-point amplitudes in planar $\mathcal{N} = 4$
supersymmetric Yang-Mills theory, making higher-loop contributions to these
amplitudes more computationally accessible. In particular, dual superconformal
symmetry and well-defined collinear limits suffice to determine uniquely the
symbols of the three-loop NMHV and four-loop MHV seven-point amplitudes. We
also show that at three loops, relaxing the dual superconformal ($\bar{Q}$)
relations and imposing dihedral symmetry (and for NMHV the absence of spurious
poles) leaves only a single ambiguity in the heptagon amplitudes. These results
point to a strong tension between the collinear properties of the amplitudes
and the Steinmann relations.Comment: 43 pages, 2 figures. v2: typos corrected; version to appear in JHE
Axial Hall effect and universality of holographic Weyl semi-metals

The holographic Weyl semimetal is a model of a strongly coupled topological
semi-metal. A topological quantum phase transition separates a topological
phase with non-vanishing anomalous Hall conductivity from a trivial state. We
investigate how this phase transition depends on the parameters of the scalar
potential (mass and quartic self coupling) finding that the quantum phase
transition persists for a large region in parameter space. We then compute the
axial Hall conductivity. The algebraic structure of the axial anomaly predicts
it to be 1/3 of the electric Hall conductivity. We find that this holds once a
non-trivial renormalization effect on the external axial gauge fields is taken
into account. Finally we show that the phase transition also occurs in a
top-down model based on a consistent truncation of type IIB supergravity.Comment: 27 pages, 9 figures, v2: references added, some typos fixed; v3 minor
  change
Transverse-momentum resummation for Higgs boson pair production at the
  LHC with top-quark mass effects

We consider Higgs boson pair production via gluon fusion in hadronic
collisions. We report the calculation of the transverse-momentum ($q_T$)
distribution of the Higgs boson pair with top-quark mass ($M_t$) effects fully
taken into account. At small values of $q_T$ we resum the
logarithmically-enhanced perturbative QCD contributions up to next-to-leading
logarithmic (NLL) accuracy. At intermediate and large values of $q_T$ we
consistently combine resummation with the ${\cal O}(\alpha_S^3)$ fixed-order
results. After integration over $q_T$, we recover the next-to-leading order
(NLO) result for the inclusive cross section with full dependence on $M_t$. We
present illustrative numerical results at LHC energies, together with an
estimate of the corresponding perturbative uncertainties, and we study the
impact of the top-quark mass effects.Comment: 11 pages, 2 figures, matches version published in JHE
From Gauss Graphs to Giants

We identify the operators in ${\cal N}=4$ super Yang-Mills theory that
correspond to ${1\over 8}$-BPS giant gravitons in AdS$_5\times$S$^5$. Our
evidence for the identification comes from (1) counting these operators and
showing agreement with independent counts of the number of giant graviton
states, and (2) by demonstrating a correspondence between correlation functions
of the super Yang-Mills operators and overlaps of the giant graviton wave
functions.Comment: 16 pages; v2: matches published versio
Experimental Targets for Photon Couplings of the QCD Axion

The QCD axion's coupling to photons is often assumed to lie in a narrow band
as a function of the axion mass. We demonstrate that several simple mechanisms,
in addition to the photophilic clockwork axion already in the literature, can
significantly extend the allowed range of couplings. Some mechanisms we present
generalize the KNP alignment scenario, widely studied as a model of inflation,
to the phenomenology of a QCD axion. In particular we present KSVZ-like
realizations of two-axion KNP alignment and of the clockwork mechanism. Such a
"confinement tower" realization of clockwork may prove useful in a variety of
model-building contexts. We also show that kinetic mixing of the QCD axion with
a lighter axion-like particle can dramatically alter the QCD axion's coupling
to photons, differing from the other models we present by allowing
non-quantized couplings. The simple models that we present fully cover the
range of axion-photon couplings that could be probed by experiments. They
motivate growing axion detection efforts over a wide space of masses and
couplings.Comment: v2: references added, minor changes, as published in JHE
Higgs production at future $e^+e^-$ colliders in the Georgi-Machacek
  model

We study how the dominant single and double SM-like Higgs ($h$) production at
future $e^+e^-$ colliders is modified in the Georgi-Machacek (GM) model. On
imposing theoretical, indirect and direct constraints, significant deviations
of $h$-couplings from their SM values are still possible; for instance, the
Higgs-gauge coupling coupling can be corrected by a factor
$\kappa_{hVV}\in[0.93,1.15]$ in the allowed parameter space. For the
Higgs-strahlung $e^+e^-\to hZ$ and vector boson fusion processes $e^+e^-\to
h\nu\bar{\nu},~he^+e^-$, the cross section could increase by $32\%$ or decrease
by $13\%$. In the case of associated production with a top quark pair
$e^+e^-\to ht\bar{t}$, the cross section can be enhanced up to several times
when the custodial triplet scalar $H_3^0$ is resonantly produced. In the
meanwhile, the double Higgs production $e^+e^-\to hhZ~(hh\nu\bar{\nu})$ can be
maximally enhanced by one order of magnitude at the resonant $H_{1,3}^0$
production. We also include exclusion limits expected from future LHC runs at
higher energy and luminosity and discuss their further constraints on the
relevant model parameters. We find that the GM model can result in likely
measurable deviations of Higgs production from the SM at future $e^+e^-$
colliders.Comment: 31 pages, 17 figures, published in JHE
Entanglement entropy of singular surfaces under relevant deformations in
  holography

In the vacuum state of a CFT, the entanglement entropy of singular surfaces
contains a logarithmic universal term which is only due to the singularity of
the entangling surface. We consider the relevant perturbation of a three
dimensional CFT for singular entangling surface. We observe that in addition to
the universal term due to the entangling surface, there is a new logarithmic
term which corresponds to a relevant perturbation of the conformal field theory
with a coefficient depending on the scaling dimension of the relevant operator.
We also find a new power law divergence in the holographic entanglement
entropy. In addition, we study the effect of a relevant perturbation in the
Gauss-Bonnet gravity for a singular entangling surface. Again a logarithmic
term shows up. This new term is proportional to both the dimension of the
relevant operator and the Gauss-Bonnet coupling. We also introduce the
renormalized entanglement entropy for a kink region which in the UV limit
reduces to a universal positive finite term.Comment: 21 pages. v2: 30 pages, title changed, one section regarding the
  renormalization added, minor corrections in text and equation
Soft hairy warped black hole entropy

We reconsider warped black hole solutions in topologically massive gravity
and find novel boundary conditions that allow for soft hairy excitations on the
horizon. To compute the associated symmetry algebra we develop a general
framework to compute asymptotic symmetries in any Chern-Simons-like theory of
gravity. We use this to show that the near horizon symmetry algebra consists of
two u(1) current algebras and recover the surprisingly simple entropy formula
$S=2\pi (J_0^+ + J_0^-)$, where $J_0^\pm$ are zero mode charges of the current
algebras. This provides the first example of a locally non-maximally symmetric
configuration exhibiting this entropy law and thus non-trivial evidence for its
universality.Comment: 24pp, v2: added appendix C and minor edit
Casimir recursion relations for general conformal blocks

We study the structure of series expansions of general spinning conformal
blocks. We find that the terms in these expansions are naturally expressed by
means of special functions related to matrix elements of Spin(d)
representations in Gelfand-Tsetlin basis, of which the Gegenbauer polynomials
are a special case. We study the properties of these functions and explain how
they can be computed in practice. We show how the Casimir equation in
Dolan-Osborn coordinates leads to a simple one-step recursion relation for the
coefficients of the series expansion of general spinning conformal block. The
form of this recursion relation is determined by 6j symbols of Spin(d-1). In
particular, it can be written down in closed form in d=3, d=4, for seed blocks
in general dimensions, or in any other situation when the required 6j symbols
can be computed. We work out several explicit examples and briefly discuss how
our recursion relation can be used for efficient numerical computation of
general conformal blocks.Comment: 84 page
An Exact Operator That Knows Its Location

We use conformal symmetry to define an AdS$_3$ proto-field $\phi$ as an exact
linear combination of Virasoro descendants of a CFT$_2$ primary operator
$\mathcal{O}$. We find that both symmetry considerations and a gravitational
Wilson line formalism lead to the same results. The operator $\phi$ has many
desirable properties; in particular it has correlators that agree with
gravitational perturbation theory when expanded at large $c$, and that
automatically take the correct form in all vacuum AdS$_3$ geometries, including
BTZ black hole backgrounds. In the future it should be possible to use $\phi$
to probe bulk locality and black hole horizons at a non-perturbative level.Comment: 24+33 pages, 2 figures; V2: refs added, terminology update
Off-shell production of top-antitop pairs in the lepton+jets channel at
  NLO QCD

The production of top-quark pairs that subsequently decay hadronically and
leptonically (lepton+jets channel) is one of the key processes for the study of
top-quark properties at the LHC. In this article, NLO QCD corrections of order
$\mathcal{O}{\left(\alpha_{\rm s}^3\alpha^{4}\right)}$ to the hadronic process
${\rm p}{\rm p}\to \mu^-\bar{\nu}_\mu{\rm b}\bar{{\rm b}} {\rm j} {\rm j}$ are
presented. The computation includes off-shell as well as non-resonant
contributions, and experimental event selections are used in order to provide
realistic predictions. The results are provided in the form of cross sections
and differential distributions. The QCD corrections are sizeable and different
from the ones of the fully leptonic channel. This is due to the different final
state where here four jets are present at leading order.Comment: 24 pages, 24 eps-figures. Matches the published versio
Asymptotically-flat supergravity solutions deep inside the black-hole
  regime

We construct an infinite family of smooth asymptotically-flat supergravity
solutions that have the same charges and angular momenta as general
supersymmetric D1-D5-P black holes, but have no horizon. These solutions
resemble the corresponding black hole to arbitrary accuracy outside of the
horizon: they have asymptotically flat regions, AdS_3 x S^3 throats and
very-near-horizon AdS_2 throats, which however end in a smooth cap rather than
an event horizon. The angular momenta of the solutions are general, and in
particular can take arbitrarily small values. Upon taking the AdS_3 x S^3
decoupling limit, we identify the holographically-dual CFT states.Comment: 49 pages, 3 figure
Evolution of the Mean Jet Shape and Dijet Asymmetry Distribution of an
  Ensemble of Holographic Jets in Strongly Coupled Plasma

Some of the most important probes of the quark-gluon plasma (QGP) produced in
heavy ion collisions come from the analysis of how the shape and energy of jets
are modified by passage through QGP. We model an ensemble of back-to-back
dijets to gain a qualitative understanding of how the shapes of the individual
jets and the asymmetry in the energy of the pairs of jets are modified by
passage through an expanding droplet of strongly coupled plasma, as modeled in
a holographic gauge theory. We do so by constructing an ensemble of strings in
the gravitational description of the gauge theory. We model QCD jets in vacuum
using strings whose endpoints move "downward" into the gravitational bulk
spacetime with some fixed small angle that represents the opening angle (ratio
of jet mass to jet energy) that the QCD jet would have in vacuum. Such strings
must be moving through the gravitational bulk at (close to) the speed of light;
they must be (close to) null. This condition does not specify the energy
distribution along the string, meaning that it does not specify the shape of
the jet being modeled. We study the dynamics of strings that are initially not
null and show that strings with a wide range of initial conditions rapidly
accelerate and become null and, as they do, develop a similar distribution of
their energy density. We use this distribution of the energy density along the
string, choose an ensemble of strings whose opening angles and energies are
distributed as in perturbative QCD, and show that we can then fix one model
parameter such that the mean jet shape in our ensemble matches that measured in
p-p collisions reasonably well. We send our strings through the plasma,
choosing the second model parameter to get a reasonable suppression in the
number of jets, and study how the mean jet shape and the dijet asymmetry are
modified, comparing both to data from LHC heavy ion collisions.Comment: References added; 34 pages, 11 figure
Dark Matter in $E_6$ Grand Unification

We discuss fermionic dark matter in non-supersymmetric $E_6$ Grand
Unification. The fundamental representation of $E_6$ contains, in addition to
the standard model fermions, exotic fermions and we argue that one of them is a
viable, interesting dark matter candidate. Its stability is guaranteed by a
discrete remnant symmetry, which is an unbroken subgroup of the $E_6$ gauge
symmetry. We compute the symmetry breaking scales and the effect of possible
threshold corrections by solving the renormalization group equations
numerically after imposing gauge coupling unification. Since the Yukawa
couplings of the exotic and the standard model fermions have a common origin,
the mass of the dark matter particles is constrained. We find a mass range of
${10^{8} \text{ GeV} \lesssim m_{DM} \lesssim 10^{12} \text{ GeV}}$ for our
$E_6$ dark matter candidate, which is within the reach of next-generation
direct detection experiments.Comment: 20 pages. 9 figure
Stimulated transitions in resonant atom Majorana mixing

Massive neutrinos demand to ask whether they are Dirac or Majorana particles.
Majorana neutrinos are an irrefutable proof of physics beyond the Standard
Model. Neutrinoless double electron capture is not a process but a virtual
$\Delta L = 2$ mixing between a parent $^AZ$ atom and a daughter $^A(Z-2)$
excited atom with two electron holes. As a mixing between two neutral atoms and
the observable signal in terms of emitted two-hole X-rays, the strategy,
experimental signature and background are different from neutrinoless double
beta decay. The mixing is resonantly enhanced for almost degeneracy and, under
these conditions, there is no irreducible background from the standard
two-neutrino channel. We reconstruct the natural time history of a nominally
stable parent atom since its production either by nature or in the laboratory.
After the time periods of atom oscillations and the decay of the short-lived
daughter atom, at observable times the relevant "stationary" states are the
mixed metastable long-lived state and the non-orthogonal short-lived excited
state, as well as the ground state of the daughter atom. We find that they have
a natural population inversion which is most appropriate for exploiting the
bosonic nature of the observed atomic transitions radiation. Among different
observables of the atom Majorana mixing, we include the enhanced rate of
stimulated X-ray emission from the long-lived metastable state by a
high-intensity X-ray beam: a gain factor of 100 can be envisaged at current
XFEL facilities. On the other hand, the historical population of the daughter
atom ground state can be probed by exciting it with a current pulsed optical
laser, showing the characteristic absorption lines: the whole population can be
excited in a shorter time than typical pulse duration.Comment: 17 pages, 4 figure
Spinors Fields in Co-dimension One Braneworlds

In this work we analyze the zero mode localization and resonances of
$1/2-$spin fermions in co-dimension one Randall-Sundrum braneworld scenarios.
We consider delta-like, domain walls and deformed domain walls membranes.
Beyond the influence of the spacetime dimension $D$ we also consider three
types of couplings: (i) the standard Yukawa coupling with the scalar field and
parameter $\eta_1$, (ii) a Yukawa-dilaton coupling with two parameters $\eta_2$
and $\lambda$ and (iii) a dilaton derivative coupling with parameter $h$.
Together with the deformation parameter $s$, we end up with five free parameter
to be considered. For the zero mode we find that the localization is dependent
of $D$, because the spinorial representation changes when the bulk
dimensionality is odd or even and must be treated separately. For case (i) we
find that in odd dimensions only one chirality can be localized and for even
dimension a massless Dirac spinor is trapped over the brane. In the cases (ii)
and (iii) we find that for some values of the parameters, both chiralities can
be localized in odd dimensions and for even dimensions we obtain that the
massless Dirac spinor is trapped over the brane. We also calculated numerically
resonances for cases (ii) and (iii) by using the transfer matrix method. We
find that, for deformed defects, the increasing of $D$ induces a shift in the
peaks of resonances. For a given $\lambda$ with domain walls, we find that the
resonances can show up by changing the spacetime dimensionality. For example,
the same case in $D=5$ do not induces resonances but when we consider $D=10$
one peak of resonance is found. Therefore the introduction of more dimensions,
diversely from the bosonic case, can change drastically the zero mode and
resonances in fermion fields.Comment: 28 pages, 7 figure
AdS/CFT Correspondence in Operator Formalism

In this paper we study the AdS/CFT correspondence in the operator formalism
without assuming the GKPW relation. We explicitly show that the low energy
spectrum of the large N limit of CFT, which is realized by a strong coupling
gauge theory, is identical to the spectrum of the free gravitational theory in
the global AdS spacetime under some assumptions which are expected to be valid.
Thus, two theories are equivalent for the low energy region under the
assumptions. Using this equivalence, the bulk local field is constructed and
the GKPW relation is derived.Comment: 26 pages, references adde