pinecone/core-2020-05-10-deduplication huggingface dataset:
The type IIB string axiverse and its low-energy phenomenology

We study closed string axions in type IIB orientifold compactifications. We
show that for natural values of the background fluxes the moduli stabilisation
mechanism of the LARGE Volume Scenario (LVS) gives rise to an axiverse
characterised by the presence of a QCD axion plus many light axion-like
particles whose masses are logarithmically hierarchical. We study the
phenomenological features of the LVS axiverse, deriving the masses of the
axions and their couplings to matter and gauge fields. We also determine when
closed string axions can solve the strong CP problem, and analyse the first
explicit examples of semi-realistic models with stable moduli and a QCD axion
candidate which is not eaten by an anomalous Abelian gauge boson. We discuss
the impact of the choice of inflationary scenario on the LVS axiverse, and
summarise the astrophysical, cosmological and experimental constraints upon it.
Moreover, we show how models can be constructed with additional light
axion-like particles that could explain some intriguing astrophysical
anomalies, and could be searched for in the next generation of axion
helioscopes and light-shining-through-a-wall experiments.Comment: 47 pages + appendices, 1 figure; v2: minor corrections and references
  adde
Wall Crossing, Quivers and Crystals

We study the spectrum of BPS D-branes on a Calabi-Yau manifold using the 0+1
dimensional quiver gauge theory that describes the dynamics of the branes at
low energies. The results of Kontsevich and Soibelman predict how the
degeneracies change. We argue that Seiberg dualities of the quiver gauge
theories, which change the basis of BPS states, correspond to crossing the
"walls of the second kind." There is a large class of examples, including local
del Pezzo surfaces, where the BPS degeneracies of quivers corresponding to one
D6 brane bound to arbitrary numbers of D4, D2 and D0 branes are counted by
melting crystal configurations. We show that the melting crystals that arise
are a discretization of the Calabi-Yau geometry. The shape of the crystal is
determined by the Calabi-Yau geometry and the background B-field, and its
microscopic structure by the quiver Q. We prove that the BPS degeneracies
computed from Q and Q' are related by the Kontsevich Soibelman formula, using a
geometric realization of the Seiberg duality in the crystal. We also show that,
in the limit of infinite B-field, the combinatorics of crystals arising from
the quivers becomes that of the topological vertex. We thus re-derive the
Gromov-Witten/Donaldson-Thomas correspondence
Spectrum of Higher Derivative 6D Chiral Supergravity

Gauged off-shell Maxwell-Einstein supergravity in six dimensions with N=(1,0)
supersymmetry has a higher derivative extension afforded by a supersymmetrized
Riemann squared term. This theory admits a supersymmetric Minkowski x S^2
compactification with a U(1) monopole of unit charge on S^2. We determine the
full spectrum of the theory on this background. We also determine the spectrum
on a non-supersymmetric version of this compactification in which the monopole
charge is different from unity, and we find the peculiar feature that there are
massless gravitini in a representation of the S^2 isometry group determined by
the monopole charge.Comment: typos correcte
MINLO: Multi-scale improved NLO

In the present work we consider the assignment of the factorization and
renormalization scales in hadron collider processes with associated jet
production, at next-to-leading order (NLO) in perturbation theory. We propose a
simple, definite prescription to this end, including Sudakov form factors to
consistently account for the distinct kinematic scales occuring in such
collisions. The scheme yields results that are accurate at NLO and, for a large
class of observables, it resums to all orders the large logarithms that arise
from kinematic configurations involving disparate scales. In practical terms
the method is most simply understood as an NLO extension of the matrix element
reweighting procedure employed in tree level matrix element-parton shower
merging algorithms. By way of a proof-of-concept, we apply the method to Higgs
and Z boson production in association with up to two jets.Comment: 27 pages, 17 figure
Conformal blocks of Chiral fields in N=2 SUSY CFT and Affine Laumon
  Spaces

We consider the problem of computing N=2 superconformal block functions. We
argue that the Kazama-Suzuki coset realization of N=2 superconformal algebra in
terms of the affine sl(2) algebra provides relations between N=2 and affine
sl(2) conformal blocks. We show that for N=2 chiral fields the corresponding
sl(2) construction of the conformal blocks is based on the ordinary highest
weight representation. We use an AGT-type correspondence to relate the
four-point sl(2) conformal block with Nekrasov's instanton partition functions
of a four-dimensional N=2 SU(2) gauge theory in the presence of a surface
operator. Since the previous relation proposed by Alday and Tachikawa requires
some special modification of the conformal block function, we revisit this
problem and find direct correspondence for the four-point conformal block. We
thus find an explicit representation for the affine sl(2) four-point conformal
block and hence obtain an explicit combinatorial representation for the N=2
chiral four-point conformal block.Comment: 15 page
Thermodynamics of Superstring on Near-extremal NS5 and Effective
  Hagedorn Behavior

We study the thermodynamical torus partition function of superstring on the
near-extremal black NS5-brane background. The exact partition function has been
computed with the helps of our previous works:[arXiv:1012.5721 [hep-th]],
[arXiv:1109.3365 [hep-th]], and naturally decomposed into two parts. The first
part is contributed from strings freely propagating in the asymptotic region,
which are identified as the superstring gas at the Hawking temperature on the
linear-dilaton background. The second part includes the contribution localized
around the `tip of cigar', which characterizes the non-extremality. Remarkably,
the latter part includes massless excitations with non-vanishing thermal
winding, which signifies that the Hagedorn-like behavior effectively appears,
even though the Hawking temperature is much lower than the Hagedorn
temperature. We also explore the high-temperature backgrounds defined by the
orbifolding along the Euclidean time direction. In those cases, the thermal
winding modes localized around the tip are found to be tachyonic, reflecting
the singularities of Euclidean backgrounds caused by orbifolding.Comment: 1+29 pages, no figure; v2 the footnote 1 is enhanced, to appear in
  JHE
Background independent holographic description : From matrix field
  theory to quantum gravity

We propose a local renormalization group procedure where length scale is
changed in spacetime dependent way. Combining this scheme with an earlier
observation that high energy modes in renormalization group play the role of
dynamical sources for low energy modes at each scale, we provide a prescription
to derive background independent holographic duals for field theories. From a
first principle construction, it is shown that the holographic theory dual to a
D-dimensional matrix field theory is a (D+1)-dimensional quantum theory of
gravity coupled with matter fields of various spins. The gravitational theory
has (D+1) first-class constraints which generate local spacetime
transformations in the bulk. The (D+1)-dimensional diffeomorphism invariance is
a consequence of the freedom to choose different local RG schemes.Comment: 34 pages, 4 figures; v2) sections VIII and IX added; v3) typos
  corrected (to appear in JHEP
A consistent picture for large penguins in D -> pi+ pi-, K+ K-

A long-standing puzzle in charm physics is the large difference between the
D0 -> K+ K- and D0 -> pi+ pi- decay rates. Recently, the LHCb and CDF
collaborations reported a surprisingly large difference between the direct CP
asymmetries, Delta A_CP, in these two modes. We show that the two puzzles are
naturally related in the Standard Model via s- and d-quark "penguin
contractions". Their sum gives rise to Delta A_CP, while their difference
contributes to the two branching ratios with opposite sign. Assuming nominal
SU(3) breaking, a U-spin fit to the D0 -> K+ pi-, pi+ K-, pi+ pi-, K+ K- decay
rates yields large penguin contractions that naturally explain Delta A_CP.
Expectations for the individual CP asymmetries are also discussed.Comment: 24 pages, 8 figure
Building an explicit de Sitter

We construct an explicit example of a de Sitter vacuum in type IIB string
theory that realizes the proposal of K\"ahler uplifting. As the large volume
limit in this method depends on the rank of the largest condensing gauge group
we carry out a scan of gauge group ranks over the Kreuzer-Skarke set of toric
Calabi-Yau threefolds. We find large numbers of models with the largest gauge
group factor easily exceeding a rank of one hundred. We construct a global
model with K\"ahler uplifting on a two-parameter model on
$\mathbb{CP}^4_{11169}$, by an explicit analysis from both the type IIB and
F-theory point of view. The explicitness of the construction lies in the
realization of a D7 brane configuration, gauge flux and RR and NS flux choices,
such that all known consistency conditions are met and the geometric moduli are
stabilized in a metastable de Sitter vacuum with spontaneous GUT scale
supersymmetry breaking driven by an F-term of the K\"ahler moduli.Comment: 61 pages, 6 figure
B-> D* zero-recoil formfactor and the heavy quark expansion in QCD: a
  systematic study

We present a QCD analysis of heavy quark mesons focussing on the B -> D*
formfactor at zero recoil, F_D*(1). An advanced treatment of the perturbative
corrections in the Wilsonian approach is presented. We estimate the
higher-order power corrections to the OPE sum rule and describe a refined
analysis of the nonresonant continuum contribution. In the framework of a
model-independent approach, we show that the inelastic contribution in the
phenomenological part of the OPE is related to the mQ-dependence of the
hyperfine splitting and conclude that the former is large, lowering the
prediction for F_D*(1) down to about 0.86. This likewise implies an enhanced
yield of radial and D-wave charm excitations in semileptonic B decays and
alleviates the problem with the inclusive yield of the wide excited states. We
also apply the approach to the expectation values of dimension 7 and 8 local
operators and to a few other issues in the heavy quark expansion.Comment: 70 pages, 13 figure
Towards the glueball spectrum from unquenched lattice QCD

We use a variational technique to study heavy glueballs on gauge
configurations generated with 2+1 flavours of ASQTAD improved staggered
fermions. The variational technique includes glueball scattering states. The
measurements were made using 2150 configurations at 0.092 fm with a pion mass
of 360 MeV. We report masses for 10 glueball states. We discuss the prospects
for unquenched lattice QCD calculations of the oddballs.Comment: 19 pages, 4 tables and 8 figures. One figure added. Now matches the
  published versio
Intersecting Flavor Branes

We consider an instance of the AdS/CFT duality where the bulk theory contains
an open string tachyon, and study the instability from the viewpoint of the
boundary field theory. We focus on the specific example of the AdS_5 X S^5
background with two probe D7 branes intersecting at general angles. For generic
angles supersymmetry is completely broken and there is an open string tachyon
between the branes. The field theory action for this system is obtained by
coupling to N =4 super Yang-Mills two N =2 hyper multiplets in the fundamental
representation of the SU(N) gauge group, but with different choices of
embedding of the two N=2 subalgebras into N=4. On the field theory side we find
a one-loop Coleman-Weinberg instability in the effective potential for the
fundamental scalars. We identify a mesonic operator as the dual of the open
string tachyon. By AdS/CFT, we predict the tachyon mass for small 't Hooft
coupling (large bulk curvature) and confirm that it violates the AdS stability
bound.Comment: 36 page
Can spacetime curvature induced corrections to Lamb shift be observable?

The Lamb shift results from the coupling of an atom to vacuum fluctuations of
quantum fields, so corrections are expected to arise when the spacetime is
curved since the vacuum fluctuations are modified by the presence of spacetime
curvature. Here, we calculate the curvature-induced correction to the Lamb
shift outside a spherically symmetric object and demonstrate that this
correction can be remarkably significant outside a compact massive
astrophysical body. For instance, for a neutron star or a stellar mass black
hole, the correction is $\sim$ 25% at a radial distance of $4GM/c^2$, $\sim$
16% at $10GM/c^2$ and as large as $\sim$ 1.6% even at $100GM/c^2$, where $M$ is
the mass of the object, $G$ the Newtonian constant, and $c$ the speed of light.
In principle, we can look at the spectra from a distant compact super-massive
body to find such corrections. Therefore, our results suggest a possible way of
detecting fundamental quantum effects in astronomical observations.Comment: 13 pages, 3 figures, slight title change, clarifications and more
  discussions added, version to be published in JHE
Large N and Bosonization in Three Dimensions

Bosonization is normally thought of as a purely two-dimensional phenomenon,
and generic field theories with fermions in D>2 are not expected be describable
by local bosonic actions, except in some special cases. We point out that 3D
SU(N) gauge theories on R^{1,1} x S^{1}_{L} with adjoint fermions can be
bosonized in the large N limit. The key feature of such theories is that they
enjoy large N volume independence for arbitrary circle size L. A consequence of
this is a large N equivalence between these 3D gauge theories and certain 2D
gauge theories, which matches a set of correlation functions in the 3D theories
to corresponding observables in the 2D theories. As an example, we focus on a
3D SU(N) gauge theory with one flavor of adjoint Majorana fermions and derive
the large-N equivalent 2D gauge theory. The extra dimension is encoded in the
color degrees of freedom of the 2D theory. We then apply the technique of
non-Abelian bosonization to the 2D theory to obtain an equivalent local theory
written purely in terms of bosonic variables. Hence the bosonized version of
the large N three-dimensional theory turns out to live in two dimensions.Comment: 30 pages, 2 tables. v2 minor revisions, references adde
Extending the Belavin-Knizhnik "wonderful formula" by the
  characterization of the Jacobian

A long-standing question in string theory is to find the explicit expression
of the bosonic measure, a crucial issue also in determining the superstring
measure. Such a measure was known up to genus three. Belavin and Knizhnik
conjectured an expression for genus four which has been proved in the framework
of the recently introduced vector-valued Teichmueller modular forms. It turns
out that for g>3 the bosonic measure is expressed in terms of such forms. In
particular, the genus four Belavin-Knizhnik "wonderful formula" has a
remarkable extension to arbitrary genus whose structure is deeply related to
the characterization of the Jacobian locus. Furthermore, it turns out that the
bosonic string measure has an elegant geometrical interpretation as generating
the quadrics in P^{g-1} characterizing the Riemann surface. All this leads to
identify forms on the Siegel upper half-space that, if certain conditions
related to the characterization of the Jacobian are satisfied, express the
bosonic measure as a multiresidue in the Siegel upper half-space. We also
suggest that it may exist a super analog on the super Siegel half-space.Comment: 15 pages. Typos corrected, refs. and comments adde
Refined Checks and Exact Dualities in Three Dimensions

We discuss and provide nontrivial evidence for a large class of dualities in
three-dimensional field theories with different gauge groups. We match the full
partition functions of the dual phases for any value of the couplings to
underpin our proposals. We focus on two classes of models. The first class,
motivated by the AdS/CFT conjecture, consists of necklace U(N) quiver gauge
theories with non chiral matter fields. We also consider orientifold
projections and establish dualities among necklace quivers with alternating
orthogonal and symplectic groups. The second class consists of theories with
tensor matter fields with free theory duals. In most of these cases the
R-symmetry mixes with IR accidental symmetries and we develop the prescription
to include their contribution into the partition function and the extremization
problem accordingly.Comment: 38 pages, 3 figure, using jheppu
Exploring Holographic General Gauge Mediation

We study models of gauge mediation with strongly coupled hidden sectors,
employing a hard wall background as an holographic dual description. The
structure of the soft spectrum depends crucially on the boundary conditions one
imposes on bulk fields at the IR wall. Generically, vector and fermion
correlators have poles at zero momentum, leading to gauge mediation by massive
vector messengers and/or generating Dirac gaugino masses. Instead, non-generic
choices of boundary conditions let one cover all of GGM parameter space.
Enriching the background with R-symmetry breaking scalars, the SSM soft term
structure becomes more constrained and similar to previously studied top-down
models, while retaining the more analytic control the present bottom-up
approach offers.Comment: 28 pages, 4 figures; v2: typos corrected and refs adde
Momentum asymmetries as CP violating observables

Three body decays can exhibit CP violation that arises from interfering
diagrams with different orderings of the final state particles. We construct
several momentum asymmetry observables that are accessible in a hadron collider
environment where some of the final state particles are not reconstructed and
not all the kinematic information can be extracted. We discuss the
complications that arise from the different possible production mechanisms of
the decaying particle. Examples involving heavy neutralino decays in
supersymmetric theories and heavy Majorana neutrino decays in Type-I seesaw
models are examined.Comment: 20 pages, 9 figures. Clarifying comments and one reference added,
  matches published versio
Kerr-AdS and its Near-horizon Geometry: Perturbations and the Kerr/CFT
  Correspondence

We investigate linear perturbations of spin-s fields in the Kerr-AdS black
hole and in its near-horizon geometry (NHEK-AdS), using the Teukolsky master
equation and the Hertz potential. In the NHEK-AdS geometry we solve the
associated angular equation numerically and the radial equation exactly. Having
these explicit solutions at hand, we search for linear mode instabilities. We
do not find any (non-)axisymmetric instabilities with outgoing boundary
conditions. This is in agreement with a recent conjecture relating the
linearized stability properties of the full geometry with those of its
near-horizon geometry. Moreover, we find that the asymptotic behaviour of the
metric perturbations in NHEK-AdS violates the fall-off conditions imposed in
the formulation of the Kerr/CFT correspondence (the only exception being the
axisymmetric sector of perturbations).Comment: 26 pages. 4 figures. v2: references added. matches published versio
4d N=2 gauge theories and quivers: the non-simply laced case

We construct the BPS quivers with superpotential for the 4d N = 2 gauge theories with non-simply laced Lie groups (B n, C n, F 4 and G 2). The construction is inspired by the BIKMSV geometric engineering of these gauge groups as non-split singular elliptic fibrations. From the categorical viewpoint of arXiv:1203.6734, the fibration of the light category ℒ (g) over the (degenerate) Gaiotto curve has a monodromy given by the action of the outer automorphism of the corresponding unfolded Lie algebra. In view of the Katz-Vafa 'matter from geometry' mechanism, the monodromic idea may be extended to the construction of (Q,W) for SYM coupled to higher matter representations. This is done through a construction we call specialization. © 2012 SISSA
Higgs After the Discovery: A Status Report

Recently, the ATLAS and CMS collaborations have announced the discovery of a
125 GeV particle, commensurable with the Higgs boson. We analyze the 2011 and
2012 LHC and Tevatron Higgs data in the context of simplified new physics
models, paying close attention to models which can enhance the diphoton rate
and allow for a natural weak-scale theory. Combining the available LHC and
Tevatron data in the ZZ* 4-lepton, WW* 2-lepton, diphoton, and b-bbar channels,
we derive constraints on the effective low-energy theory of the Higgs boson. We
map several simplified scenarios to the effective theory, capturing numerous
new physics models such as supersymmetry, composite Higgs, dilaton. We further
study models with extended Higgs sectors which can naturally enhance the
diphoton rate. We find that the current Higgs data are consistent with the
Standard Model Higgs boson and, consequently, the parameter space in all models
which go beyond the Standard Model is highly constrained.Comment: 37 pages; v2: ATLAS dijet-tag diphoton channel added, dilaton and
  doublet-singlet bugs corrected, references added; v3: ATLAS WW channel
  included, comments and references adde
The radiation pattern of a QCD antenna in a dense medium

We calculate the radiation spectrum off a qq-bar pair of a fixed opening
angle theta_qq-bar traversing a medium of length L. Multiple interactions with
the medium are handled in the harmonic oscillator approximation, valid for soft
gluon emissions. We discuss the time-scales relevant to the decoherence of
correlated partons traversing the medium and demonstrate how this relates to
the hard scale that govern medium-induced radiation. For large angle radiation,
the hard scale is given by Qhard = max(r_perp^{-1}, Qs), where r_perp =
theta_qq-bar L is the probed transverse size and Qs is the maximal transverse
momentum accumulated by the emitted gluon in the medium. These situations
define in turn two distinct regimes, which we call "dipole" and "decoherence"
regimes, respectively, and which are discussed in detail. A feature common to
both cases is that coherence of the radiation is restored at large transverse
momenta, k_\perp > Qhard.Comment: 44 pages, 8 figure
Double Handled Brane Tilings

We classify the first few brane tilings on a genus 2 Riemann surface and
identify their toric Calabi-Yau moduli spaces. These brane tilings are
extensions of tilings on the 2-torus, which represent one of the largest known
classes of 4d N=1 superconformal field theories for D3-branes. The
classification consists of 16 distinct genus 2 brane tilings with up to 8
quiver fields and 4 superpotential terms. The Higgs mechanism is used to relate
the different theories.Comment: 86 pages, 43 figures, 13 table
Higher derivative corrections to Lifshitz backgrounds

We explore the effect of curvature-square corrections on Lifshitz solutions
to the Einstein-Maxwell-dilaton system. After exhibiting the renormalized
Lifshitz scaling solution to the system with parameterized R^2 corrections, we
turn to a toy model with coupling g(\phi)C_{\mu\nu\rho\sigma}^2 and demonstrate
that such a term can both stabilize the dilaton and resolve the Lifshitz
horizon to AdS_2 x R^2. As an example, we construct numerical flows from AdS_4
in the UV to an intermediate Lifshitz region and then to AdS_2 x R^2 in the
deep IR.Comment: 25 pages, 8 figures, references added and minor correction to
  Appendix