pinecone/core-2020-05-10-deduplication huggingface dataset:
Magnetic Monopoles and Free Fractionally Charged States at Accelerators
  and in Cosmic Rays

Unified theories of strong, weak and electromagnetic interactions which have
electric charge quantization predict the existence of topologically stable
magnetic monopoles. Intermediate scale monopoles are comparable with detection
energies of cosmic ray monopoles at IceCube and other cosmic ray experiments.
Magnetic monopoles in some models can be significantly lighter and carry two,
three or possibly even higher quanta of the Dirac magnetic charge. They could
be light enough for their effects to be detected at the LHC either directly or
indirectly. An example based on a D-brane inspired $SU(3)_C\times SU(3)_L\times
SU(3)_R$ (trinification) model with the monopole carrying three quanta of Dirac
magnetic charge is presented. These theories also predict the existence of
color singlet states with fractional electric charge which may be accessible at
the LHC.Comment: 18 pages, 2 figures, minor revisions, references adde
LSP baryogenesis and neutron-antineutron oscillations from R-parity
  violation

R-parity and baryon number violating operators can be allowed in the
Supersymmetric Standard Model and thus lead to interesting baryon number
violating processes such as neutron-antineutron oscillations and baryogenesis
of the Universe via the decay of the lightest supersymmetric particle (LSP).
Adopting the LSP baryogenesis mechanism realized by the late decay of the
axino, we identify a single coupling lambda''_313 as a common origin for the
matter-antimatter asymmetry of the Universe as well as potentially observable
neutron-antineutron oscillation rates. From this, rather strong constraints on
the supersymmetry breaking masses and the axion decay constant are obtained.
The favoured parameter space of lambda''_313 ~ 0.1 and sub-TeV masses for the
relevant sparticles is readily accessible by the current and future LHC
searches.Comment: 17 pages, 6 figures, added references, version accepted for
  publication in JHE
Five-loop renormalisation of QCD in covariant gauges

We present the complete set of vertex, wave function and charge
renormalisation constants in QCD in a general simple gauge group and with the
complete dependence on the covariant gauge parameter $\xi$ in the minimal
subtraction scheme of conventional dimensional regularisation. Our results
confirm all already known results, which were obtained in the Feynman gauge,
and allow the extraction of other useful gauges such as the Landau gauge. We
use these results to extract the Landau gauge five-loop anomalous dimensions of
the composite operator $A^2$ as well as the Landau gauge scheme independent
gluon, ghost and fermion propagators at five loops.Comment: 17 pages; FORM and Mathematica result files available with the
  source; corrected minor typos, added references, journal ref, 1 remark, 1
  note and 1 additional result fil
SYK Models and SYK-like Tensor Models with Global Symmetry

In this paper, we study an SYK model and an SYK-like tensor model with global
symmetry. First, we study the large $N$ expansion of the bi-local collective
action for the SYK model with manifest global symmetry. We show that the global
symmetry is enhanced to a local symmetry at strong coupling limit, and the
corresponding symmetry algebra is the Kac-Moody algebra. The emergent local
symmetry together with the emergent reparametrization is spontaneously and
explicit broken. This leads to a low energy effective action. We evaluate four
point functions, and obtain spectrum of our model. We derive the low energy
effective action and analyze the chaotic behavior of the four point functions.
We also consider the recent 3D gravity conjecture for our model.
  We also introduce an SYK-like tensor model with global symmetry. We first
study chaotic behavior of four point functions in various channels for the
rank-3 case, and generalize this into a rank-$(q-1)$ tensor model.Comment: 61 pages, 8 figures; v2: typos corrected, references added, appendix
  D revised; v3: typos corrected, 1 figure added for clarification, substantial
  revisions and clarifications (conclusions unchanged
Anti-D3 branes and moduli in non-linear supergravity

Anti-D3 branes and non-perturbative effects in flux compactifications
spontaneously break supersymmetry and stabilise moduli in a metastable de
Sitter vacua. The low energy 4D effective field theory description for such
models would be a supergravity theory with non-linearly realised supersymmetry.
Guided by string theory modular symmetry, we compute this non-linear
supergravity theory, including dependence on all bulk moduli. Using either a
constrained chiral superfield or a constrained vector field, the uplifting
contribution to the scalar potential from the anti-D3 brane can be
parameterised either as an F-term or Fayet-Iliopoulos D-term. Using again the
modular symmetry, we show that 4D non-linear supergravities that descend from
string theory have an enhanced protection from quantum corrections by
non-renormalisation theorems. The superpotential giving rise to metastable de
Sitter vacua is robust against perturbative string-loop and $\alpha'$
corrections.Comment: 33 page
Top-pair production at the LHC through NNLO QCD and NLO EW

In this work we present for the first time predictions for top-quark pair
differential distributions at the LHC at NNLO QCD accuracy and including EW
corrections. For the latter we include not only contributions of ${\cal
O}(\alpha_s^2 \alpha)$, but also those of order ${\cal O}(\alpha_s \alpha^2)$
and ${\cal O}( \alpha^3)$. Besides providing phenomenological predictions for
all main differential distributions with stable top quarks, we also study the
following issues. 1) The effect of the photon PDF on top-pair spectra: we find
it to be strongly dependent on the PDF set used -- especially for the top $p_T$
distribution. 2) The difference between the additive and multiplicative
approaches for combining QCD and EW corrections: with our scale choice, we find
relatively small differences between the central predictions, but reduced scale
dependence within the multiplicative approach. 3) The potential effect from the
radiation of heavy bosons on inclusive top-pair spectra: we find it to be,
typically, negligible.Comment: 22 pages, 7 figures, version published in JHEP, results are attached
  in electronic form, results and additional material available from this
  website: http://www.precision.hep.phy.cam.ac.uk/results/ttbar-nnloqcd-nloew
Butterfly Velocities for Holographic Theories of General Spacetimes

The butterfly velocity characterizes the spread of correlations in a quantum
system. Recent work has provided a method of calculating the butterfly velocity
of a class of boundary operators using holographic duality. Utilizing this and
a presumed extension of the canonical holographic correspondence of AdS/CFT, we
investigate the butterfly velocities of operators with bulk duals living in
general spacetimes. We analyze some ubiquitous issues in calculating butterfly
velocities using the bulk effective theory, and then extend the previously
proposed method to include operators in entanglement shadows. We explicitly
compute butterfly velocities for bulk local operators in the holographic theory
of flat Friedmann-Robertson-Walker spacetimes and find a universal scaling
behavior for the spread of operators in the boundary theory, independent of
dimension and fluid components. This result may suggest that a Lifshitz field
theory with z = 4 is the appropriate holographic dual for these spacetimes.Comment: 14 pages, 3 figures; fixed calculational error, removed the
  associated erroneous discussions on monotonicit
The role of the $S_3$ GUT leptoquark in flavor universality and collider
  searches

We investigate the ability of the $S_3$ scalar leptoquark to address the
recent hints of lepton universality violation in $B$ meson decays. The $S_3$
leptoquark with quantum numbers $(\overline{\mathbf{3}},\mathbf{3},1/3)$
naturally emerges in the context of an $SU(5)$ GUT model without any conflict
with the stringent limits from observed nucleon stability. Scalar leptoquark
$S_3$ with left-handed couplings to 2nd and 3rd generations of charged leptons
and down-type quarks seems well-suited to address both $R_{K^{(*)}}$ and
$R_{D^{(*)}}$. We quantify this suitability with numerical fits to a plethora
of relevant flavor observables. The proposed $SU(5)$ model calls for a second
leptoquark state, i.e., $\tilde{R}_2$ with quantum numbers
$(\mathbf{3},\mathbf{2},1/6)$, if one is to generate gauge coupling unification
and neutrino mass. We accordingly include it in our study to investigate
$\tilde{R}_2$'s ability to offset adverse effects of $S_3$ and thus improve a
quality of numerical fits. A global fit of the leptoquark Yukawa couplings
shows that large couplings of light $S_3$ to $\tau$ leptons are preferred. We
furthermore identify $B \to K^{(*)} \bar\nu\nu$ as the most sensitive channel
to probe the preferred region of parameter space. Large couplings of $S_3$ to
$\tau$ leptons are finally confronted with the experimental searches for $\tau$
final states at the Large Hadron Collider. These searches comprise a study of
decay products of the leptoquark pair production, as well as, and more
importantly, an analysis of the high-mass $\tau\tau$ final states.Comment: Published version. 32 pages, 6 figure
Boundary Conformal Field Theory and a Boundary Central Charge

We consider the structure of current and stress tensor two-point functions in
conformal field theory with a boundary. The main result of this paper is a
relation between a boundary central charge and the coefficient of a
displacement operator correlation function in the boundary limit. The boundary
central charge under consideration is the coefficient of the product of the
extrinsic curvature and the Weyl curvature in the conformal anomaly. Along the
way, we describe several auxiliary results. Three of the more notable are as
follows: (1) we give the bulk and boundary conformal blocks for the current
two-point function; (2) we show that the structure of these current and stress
tensor two-point functions is essentially universal for all free theories; (3)
we introduce a class of interacting conformal field theories with boundary
degrees of freedom, where the interactions are confined to the boundary. The
most interesting example we consider can be thought of as the infrared fixed
point of graphene. This particular interacting conformal model in four
dimensions provides a counterexample of a previously conjectured relation
between a boundary central charge and a bulk central charge. The model also
demonstrates that the boundary central charge can change in response to
marginal deformations.Comment: 75 pages, 4 figures; v2: references added. v3: comments on anomalous
  dimension and references added. v4: minor corrections, published versio
Holographic microstate counting for AdS$_4$ black holes in massive IIA
  supergravity

We derive the Bekenstein-Hawking entropy for a class of BPS black holes in
the massive type IIA supergravity background AdS$_4 \times S^6$ from a
microscopic counting of supersymmetric ground states in a holographically dual
field theory. The counting is performed by evaluating the topologically twisted
index of three-dimensional $\mathcal{N}=2$ Chern-Simons-matter gauge theories
in the large $N$ limit. The $\mathcal{I}$-extremization principle is shown to
match the attractor mechanism for the near-horizon geometries constructed in
the four-dimensional dyonic $\mathcal{N}=2$ gauged supergravity, that arises as
a consistent truncation of massive type IIA supergravity on $S^6$. In
particular, our results prove that the imaginary part of the three-dimensional
partition functions plays a crucial r\^ole in holography.Comment: 33 pages; v2: ref added, typos corrected; v3: published versio
Towards next-to-next-to-leading-log accuracy for the width difference in
  the $B_s-\bar{B}_s$ system: fermionic contributions to order $(m_c/m_b)^0$
  and $(m_c/m_b)^1$

We calculate a class of three-loop Feynman diagrams which contribute to the
next-to-next-to-leading logarithmic approximation for the width difference
$\Delta\Gamma_{s}$ in the $B_s-\bar{B}_s$ system. The considered diagrams
contain a closed fermion loop in a gluon propagator and constitute the order
$\alpha_s^2 N_f$, where $N_f$ is the number of light quarks. Our results entail
a considerable correction in that order, if $\Delta\Gamma_{s}$ is expressed in
terms of the pole mass of the bottom quark. If the $\overline{MS}$ scheme is
used instead, the correction is much smaller. As a result, we find a decrease
of the scheme dependence. Our result also indicates that the usually quoted
value of the NLO renormalization scale dependence underestimates the
perturbative error.Comment: We corrected a typographical mistake in Eq. (4.18), made larger axis
  labels in Fig.2. Version accepted by JHE
The 3.5 keV Line from Stringy Axions

An interesting result in particle astrophysics is the recent detection of an
unexplained 3.5 keV line from galaxy clusters. A promising model, which can
explain the morphology of the signal and its non-observation in dwarf
spheroidal galaxies, involves a 7 keV dark matter particle decaying into a pair
of ultra-light axions that convert into photons in the magnetic field of the
clusters. Given that light axions emerge naturally in 4D string vacua, in this
paper we present a microscopic realisation of this model within the framework
of type IIB flux compactifications. Dark matter is a local closed string axion
which develops a tiny mass due to subdominant poly-instanton corrections to the
superpotential and couples via kinetic mixing to an almost massless open string
axion living on a D3-brane at a singularity. The interaction of this
ultra-light axion with photons is induced by U(1) kinetic mixing. After
describing the Calabi-Yau geometry and the brane set-up, we discuss in depth
moduli stabilisation, the resulting mass spectrum and the strength of all
relevant couplings.Comment: 27 pages + appendices, 1 figure; typos corrected, references added,
  additional comments on the cosmological history and DM production in the
  conclusion
A New Class of de Sitter Vacua in Type IIB Large Volume
  Compactifications

We construct a new class of metastable de Sitter vacua of flux
compactifications of type IIB string theory. These solutions provide a natural
extension of the `Large Volume Scenario' anti-de Sitter vacua, and can
analogously be realised at parametrically large volume and weak string
coupling, using standard ${\cal N}=1$ supergravity. For these new vacua, a
positive vacuum energy is achieved from the inclusion of a small amount of
flux-induced supersymmetry breaking in the complex structure and axio-dilaton
sector, and no additional `uplift' contribution (e.g.~from anti-branes) is
required. We show that the approximate no-scale structure of the effective
theory strongly influences the spectrum of the stabilised moduli: one complex
structure modulus remains significantly lighter than the supersymmetry breaking
scale, and metastability requires only modest amounts of tuning. After
discussing these general results, we provide a recipe for constructing de
Sitter vacua on a given compactification manifold, and give an explicit example
of a de Sitter vacuum for the compactification on the Calabi-Yau orientifold
realised in $\mathbb{CP}^4_{11169}$. Finally, we note that these solutions have
intriguing implications for phenomenology, predicting no superpartners in the
spectrum below $\sim$50 TeV, and no WIMP dark matter.Comment: 34 page
Newton-Cartan Gravity and Torsion

We compare the gauging of the Bargmann algebra, for the case of arbitrary
torsion, with the result that one obtains from a null-reduction of General
Relativity. Whereas the two procedures lead to the same result for
Newton-Cartan geometry with arbitrary torsion, the null-reduction of the
Einstein equations necessarily leads to Newton-Cartan gravity with zero
torsion. We show, for three space-time dimensions, how Newton-Cartan gravity
with arbitrary torsion can be obtained by starting from a Schroedinger field
theory with dynamical exponent z=2 for a complex compensating scalar and next
coupling this field theory to a z=2 Schroedinger geometry with arbitrary
torsion. The latter theory can be obtained from either a gauging of the
Schroedinger algebra, for arbitrary torsion, or from a null-reduction of
conformal gravity.Comment: 21 page
Suppression of maximal linear gluon polarization in angular asymmetries

We perform a phenomenological analysis of the $\cos 2 \phi $ azimuthal
asymmetry in virtual photon plus jet production induced by the linear
polarization of gluons in unpolarized $pA$ collisions. Although the linearly
polarized gluon distribution becomes maximal at small $x$, TMD evolutionleads
to a Sudakov suppression of the asymmetry with increasing invariant mass of the
$\gamma^*$-jet pair. Employing a small-$x$ model input distribution, the
asymmetry is found to be strongly suppressed under TMD evolution, but still
remains sufficiently large to be measurable in the typical kinematical region
accessible at RHIC or LHC at moderate photon virtuality, whereas it is expected
to be negligible in $Z/W$-jet pair production at LHC. We point out the optimal
kinematics for RHIC and LHC studies, in order to expedite the first
experimental studies of the linearly polarized gluon distribution through this
process. We further argue that this is a particularly clean process to test the
$k_t$-resummation formalism in the small-$x$ regime.Comment: 11 pages, 6 figure
Bounds for OPE coefficients on the Regge trajectory

We consider the Regge limit of the CFT correlation functions $\langle {\cal
J} {\cal J} {\cal O}{\cal O}\rangle$ and $\langle TT {\cal O}{\cal O}\rangle$,
where ${\cal J}$ is a vector current, $T$ is the stress tensor and ${\cal O}$
is some scalar operator. These correlation functions are related by a type of
Fourier transform to the AdS phase shift of the dual 2-to-2 scattering process.
AdS unitarity was conjectured some time ago to be positivity of the imaginary
part of this bulk phase shift. This condition was recently proved using purely
CFT arguments. For large $N$ CFTs we further expand on these ideas, by
considering the phase shift in the Regge limit, which is dominated by the
leading Regge pole with spin $j(\nu)$, where $\nu$ is a spectral parameter. We
compute the phase shift as a function of the bulk impact parameter, and then
use AdS unitarity to impose bounds on the analytically continued OPE
coefficients $C_{{\cal J}{\cal J}j(\nu)}$ and $C_{TTj(\nu)}$ that describe the
coupling to the leading Regge trajectory of the current ${\cal J}$ and stress
tensor $T$. AdS unitarity implies that the OPE coefficients associated to
non-minimal couplings of the bulk theory vanish at the intercept value $\nu=0$,
for any CFT. Focusing on the case of large gap theories, this result can be
used to show that the physical OPE coefficients $C_{{\cal J}{\cal J}T}$ and
$C_{TTT}$, associated to non-minimal bulk couplings, scale with the gap
$\Delta_g$ as $\Delta_g^{-2}$ or $\Delta_g^{-4}$. Also, looking directly at the
unitarity condition imposed at the OPE coefficients $C_{{\cal J}{\cal J}T}$ and
$C_{TTT}$ results precisely in the known conformal collider bounds, giving a
new CFT derivation of these bounds. We finish with remarks on finite $N$
theories and show directly in the CFT that the spin function $j(\nu)$ is
convex, extending this property to the continuation to complex spin.Comment: 47 pages, 3 figures, v2: JHEP versio
Small-$x$ Asymptotics of the Gluon Helicity Distribution

We determine the small-$x$ asymptotics of the gluon helicity distribution in
a proton at leading order in perturbative QCD at large $N_c$. To achieve this,
we begin by evaluating the dipole gluon helicity TMD at small $x$. In the
process we obtain an interesting new result: in contrast to the unpolarized
dipole gluon TMD case, the operator governing the small-$x$ behavior of the
dipole gluon helicity TMD is different from the operator corresponding to the
polarized dipole scattering amplitude (used in our previous work to determine
the small-$x$ asymptotics of the quark helicity distribution). We then
construct and solve novel small-$x$ large-$N_c$ evolution equations for the
operator related to the dipole gluon helicity TMD. Our main result is the
small-$x$ asymptotics for the gluon helicity distribution: $\Delta G \sim
\left( \tfrac{1}{x} \right)^{\alpha_h^G}$ with $\alpha_h^G = \tfrac{13}{4
\sqrt{3}} \, \sqrt{\tfrac{\alpha_s \, N_c}{2 \pi}} \approx 1.88 \,
\sqrt{\tfrac{\alpha_s \, N_c}{2 \pi}}$. We note that the power $\alpha_h^G$ is
approximately 20$\%$ lower than the corresponding power $\alpha_h^q$ for the
small-$x$ asymptotics of the quark helicity distribution defined by $\Delta q
\sim \left( \tfrac{1}{x} \right)^{\alpha_h^q}$ with $\alpha_h^q =
\tfrac{4}{\sqrt{3}} \, \sqrt{\tfrac{\alpha_s \, N_c}{2 \pi}} \approx 2.31 \,
\sqrt{\tfrac{\alpha_s \, N_c}{2 \pi}}$ found in our earlier work.Comment: 36 pages, 9 figures; v3: minus signs and factors of 2 corrected, main
  results remained the sam
Operator bases, $S$-matrices, and their partition functions

Relativistic quantum systems that admit scattering experiments are
quantitatively described by effective field theories, where $S$-matrix
kinematics and symmetry considerations are encoded in the operator spectrum of
the EFT. In this paper we use the $S$-matrix to derive the structure of the EFT
operator basis, providing complementary descriptions in (i) position space
utilizing the conformal algebra and cohomology and (ii) momentum space via an
algebraic formulation in terms of a ring of momenta with kinematics implemented
as an ideal. These frameworks systematically handle redundancies associated
with equations of motion (on-shell) and integration by parts (momentum
conservation).
  We introduce a partition function, termed the Hilbert series, to enumerate
the operator basis--correspondingly, the $S$-matrix--and derive a matrix
integral expression to compute the Hilbert series. The expression is general,
easily applied in any spacetime dimension, with arbitrary field content and
(linearly realized) symmetries.
  In addition to counting, we discuss construction of the basis. Simple
algorithms follow from the algebraic formulation in momentum space. We
explicitly compute the basis for operators involving up to $n=5$ scalar fields.
This construction universally applies to fields with spin, since the operator
basis for scalars encodes the momentum dependence of $n$-point amplitudes.
  We discuss in detail the operator basis for non-linearly realized symmetries.
In the presence of massless particles, there is freedom to impose additional
structure on the $S$-matrix in the form of soft limits. The most na\"ive
implementation for massless scalars leads to the operator basis for pions,
which we confirm using the standard CCWZ formulation for non-linear
realizations.Comment: 75 pages plus appendice