pinecone/core-2020-05-10-deduplication huggingface dataset:
Sigma models with off-shell N=(4,4) supersymmetry and noncommuting
  complex structures

We describe the conditions for extra supersymmetry in N=(2,2) supersymmetric
nonlinear sigma models written in terms of semichiral superfields. We find that
some of these models have additional off-shell supersymmetry. The (4,4)
supersymmetry introduces geometrical structures on the target-space which are
conveniently described in terms of Yano f-structures and Magri-Morosi
concomitants. On-shell, we relate the new structures to the known
bi-hypercomplex structures.Comment: 20 pages; v2: significant corrections, clarifications, and
  reorganization; v3: discussion of supersymmetry vs twisted supersymmetry
  added, relevant signs corrected
Desensitizing Inflation from the Planck Scale

A new mechanism to control Planck-scale corrections to the inflationary eta
parameter is proposed. A common approach to the eta problem is to impose a
shift symmetry on the inflaton field. However, this symmetry has to remain
unbroken by Planck-scale effects, which is a rather strong requirement on
possible ultraviolet completions of the theory. In this paper, we show that the
breaking of the shift symmetry by Planck-scale corrections can be
systematically suppressed if the inflaton field interacts with a conformal
sector. The inflaton then receives an anomalous dimension in the conformal
field theory, which leads to sequestering of all dangerous high-energy
corrections. We analyze a number of models where the mechanism can be seen in
action. In our most detailed example we compute the exact anomalous dimensions
via a-maximization and show that the eta problem can be solved using only
weakly-coupled physics.Comment: 34 pages, 3 figures
Species Doublers as Super Multiplets in Lattice Supersymmetry: Exact
  Supersymmetry with Interactions for D=1 N=2

We propose a new lattice superfield formalism in momentum representation
which accommodates species doublers of the lattice fermions and their bosonic
counterparts as super multiplets. We explicitly show that one dimensional N=2
model with interactions has exact Lie algebraic supersymmetry on the lattice
for all super charges. In coordinate representation the finite difference
operator is made to satisfy Leibnitz rule by introducing a non local product,
the ``star'' product, and the exact lattice supersymmetry is realized. The
standard momentum conservation is replaced on the lattice by the conservation
of the sine of the momentum, which plays a crucial role in the formulation.
Half lattice spacing structure is essential for the one dimensional model and
the lattice supersymmetry transformation can be identified as a half lattice
spacing translation combined with alternating sign structure. Invariance under
finite translations and locality in the continuum limit are explicitly
investigated and shown to be recovered. Supersymmetric Ward identities are
shown to be satisfied at one loop level. Lie algebraic lattice supersymmetry
algebra of this model suggests a close connection with Hopf algebraic exactness
of the link approach formulation of lattice supersymmetry.Comment: 34 pages, 2 figure
Collider signatures of sterile neutrinos in models with a gauge-singlet
  Higgs

Sterile neutrinos have been invoked to explain the observed neutrino masses,
but they can also have significant implications for cosmology and accelerator
experiments. We explore the collider signatures of a simple extension of the
Standard Model, where sterile neutrinos acquire their mass after electroweak
symmetry breaking, via their coupling to a real singlet Higgs. In this model,
heavy sterile neutrinos can be produced in accelerators from decays of the
Higgs bosons. Their own decay can yield distinct signals, suggesting both the
presence of an extended Higgs sector and the coupling of the singlet fermions
to the latter. In the same scenario, a relic matter abundance arises from the
decay of the singlet Higgs into weakly coupled keV sterile neutrinos. The
coupling of the Higgs doublet to particles outside the Standard Model relaxes
the current experimental bounds on its mass.Comment: v2: JHEP accepted version, 19 pages, 9 figure
Non-supersymmetric Extremal RN-AdS Black Holes in N=2 Gauged
  Supergravity

We investigate extremal Reissner-Nordstrom-AdS black holes in
four-dimensional N=2 abelian gauged supergravity. We find a new attractor
equation which is not reduced to the one in the asymptotically flat spacetime.
Focusing on so-called the T^3-model with a single neutral vector multiplet, we
obtain non-supersymmetric extremal Reissner-Nordstrom-AdS black hole solutions
with regular event horizon in the D0-D4 and the D2-D6 charge configurations.
The negative cosmological constant emerges even without the Fayet-Iliopoulos
parameters. Furthermore, we also argue the formal description of the
non-supersymmetric black hole solutions of the T^3-model and the STU-model in
generic configurations.Comment: 23 pages, accepted version in JHE
Quantum finite-size effects for dyonic magnons in the AdS_4 x CP^3

We compute quantum corrections to finite-size effects for various dyonic
giant magnons in the AdS_4 x CP^3 in two different approaches. The off-shell
algebraic curve method is used to quantize the classical string configurations
in semi-classical way and to compute the corrections to the string energies.
These results are compared with the F-term L\"uscher formula based on the
S-matrix of the AdS_4 / CFT_3. The fact that the two results match exactly
provides another stringent test for the all-loop integrability conjecture and
the exact S-matrix based on it.Comment: 21 pages, No figures, corrected typos, added some reference
Heterotic MSSM on a Resolved Orbifold

We construct an MSSM with three generations from the heterotic string
compactified on a smooth 6D internal manifold using Abelian gauge fluxes only.
The compactification space is obtained as a resolution of the T6/Z2xZ2xZ2-free
orbifold. The Z2-free involution of such a resolution breaks the SU(5) GUT
group down to the SM gauge group using a suitably chosen (freely acting) Wilson
line. Surprisingly, the spectrum on a given resolution is larger than the one
on the corresponding orbifold taking into account the branching and Higgsing
due to the blow-up modes. The existence of extra resolution states is closely
related to the fact that the resolution procedure is not unique. Rather, the
various resolutions are connected to each other by flop transitions.Comment: 59 pages, 7 figure
Fourteen new stationary points in the scalar potential of SO(8)-gauged
  N=8, D=4 supergravity

The list of six previously known nontrivial stationary points in the scalar
potential of N=8, D=4 supergravity with gauge group SO(8) is extended by
fourteen new entries, whose properties have been obtained numerically using the
sensitivity backpropagation technique. Eight of the new solutions break the
gauge group completely, while three have a residual symmetry of U(1). Three
further ones break the gauge group to U(1)xU(1), and while the approximate
numerical data are somewhat inconclusive, there is evidence that one of these
may have a residual N=1 supersymmetry, hence correspond to a stable vacuum. It
must be pointed out that this list of new solutions most likely is not
exhaustive.Comment: 23 pages; typo fixes and some adjustments to text; fermion mass
  matrix eigenvalues liste
Phase Structure and Compactness

In order to study the influence of compactness on low-energy properties, we
compare the phase structures of the compact and non-compact two-dimensional
multi-frequency sine-Gordon models. It is shown that the high-energy scaling of
the compact and non-compact models coincides, but their low-energy behaviors
differ. The critical frequency $\beta^2 = 8\pi$ at which the sine-Gordon model
undergoes a topological phase transition is found to be unaffected by the
compactness of the field since it is determined by high-energy scaling laws.
However, the compact two-frequency sine-Gordon model has first and second order
phase transitions determined by the low-energy scaling: we show that these are
absent in the non-compact model.Comment: 21 pages, 5 figures, minor changes, final version, accepted for
  publication in JHE
Boundary stress tensor and counterterms for weakened AdS_3 asymptotic in
  New Massive Gravity

Resorting to the notion of a stress tensor induced on the boundary of a
spacetime, we compute the conserved charges associated to exact solutions of
New Massive Gravity that obey weakened versions of AdS_3 asymptotic boundary
conditions. The computation requires the introduction of additional
counterterms, which play the role of regularizing the semiclassical stress
tensor in the boundary theory. We show that, if treated appropriately,
different ways of prescribing asymptotically AdS_3 boundary conditions yield
finite conserved charges for the solutions. The consistency of the construction
manifests itself in that the charges of hairy asymptotically AdS_3 black holes
computed by this holography-inspired method exactly match the values required
for the Cardy formula to reproduce the black hole entropy. We also consider new
solutions to the equations of motion of New Massive Gravity, which happen to
fulfill Brown-Henneaux boundary conditions despite not being Einstein
manifolds. These solutions are shown to yield vanishing boundary stress tensor.
The results obtained in this paper can be regarded as consistency checks for
the prescription proposed in arXiv:1001.3598.Comment: 13 pages. v2 minor typos correcte
The MHV Lagrangian for a spontaneously broken gauge theory

Starting from the standard Lagrangian for a SU(2) x U(1) gauge theory plus a
Higgs field we derive the corresponding "maximal helicity violating" (MHV)
Lagrangian. From this MHV Lagrangian one deduces simple diagrammatic rules for
the calculation of multi-particle scattering amplitudes. We arrive at the MHV
Lagrangian by a canonical change of the field variables in the light-cone
gauge. We comment on the modifications which occur in a spontaneously broken
gauge theory as compared to a pure (unbroken) Yang-Mills theory.Comment: 29 page
Boundary Giant Magnons and Giant Gravitons

We construct the full set of boundary giant magnons on $\mathbb{R}\times
S^{2}$ attached to the maximal $Z=0$ giant graviton by mapping from the general
solution to static sine-Gordon theory on the interval and compute the values of
$\Delta-J$ at finite $J$, including the leading order corrections when $J$ is
large. We then consider the Born-Infeld theory of the giant graviton itself to
construct BIon spike solutions that correspond to the world volume description
of the boundary giant magnons at finite $J$.Comment: 35 pages, 10 figures. Minor corrections onl
On gauge transformation property of coordinate independent SO(9) vector
  states in SU(2) Matrix Theory

We investigate coordinate independent SO(9) vector states in SU(2) Matrix
theory. There are 36 vector states, and we determine what representations of
SU(2) they are decomposed into. Among them we find a unique set of states
transforming in adjoint representation. We show that this set of states can
appear as the linear term in the coordinate matrices in Taylor expansion of
zero energy bound state wavefunction around the origin i.e. it satisfies the
condition of full supersymmetry.Comment: 21 pages, no figure, v2: minor correction v3: signs in (3.46) and
  (3.51) corrected, further calculation on the linear term of the expansion of
  the wavefunction added, and the conclusion about it changed, v3: minor change
  in the references, version published in JHE
Singlet Extensions of the MSSM in the Quiver Landscape

We map out possible extensions of the MSSM in the context of type II string
theory. We systematically investigate three-stack and four-stack quivers which
realize the MSSM spectrum with the addition of a single MSSM singlet S with an
allowed S H_u H_d term, which can lead to a dynamical electroweak-scale
mu-term. We present the three quivers which satisfy stringent string-theoretic
and phenomenological constraints, including the presence of non-zero masses for
all three families of quarks and leptons, the perturbative and non-perturbative
absence of R-parity violating couplings and rapid dimension-five proton decay,
and a mechanism for small neutrino masses. We find that these quivers can
realize many models in the class of singlet-extended (supersymmetric) standard
models, as D-instanton effects can in principle generate a superpotential of
the form f(S), where f is a polynomial. Finally, we address the issue of the
stabilization and decoupling of charged moduli which generically appear in
D-instanton corrections to the superpotential.Comment: 15 pages, plus references. Version 2: accepted to JHE
Viability of MSSM scenarios at very large tan(beta)

We investigate the MSSM with very large tan(beta) > 50, where the fermion
masses are strongly affected by loop-induced couplings to the "wrong" Higgs,
imposing perturbative Yukawa couplings and constraints from flavour physics.
Performing a low-energy scan of the MSSM with flavour-blind soft terms, we find
that the branching ratio of B->tau nu and the anomalous magnetic moment of the
muon are the strongest constraints at very large tan(beta) and identify the
viable regions in parameter space. Furthermore we determine the scale at which
the perturbativity of the Yukawa sector breaks down, depending on the
low-energy MSSM parameters. Next, we analyse the very large tan(beta) regime of
General Gauge Mediation (GGM) with a low mediation scale. We investigate the
requirements on the parameter space and discuss the implied flavour
phenomenology. We point out that the possibility of a vanishing Bmu term at a
mediation scale M = 100 TeV is challenged by the experimental data on B->tau nu
and the anomalous magnetic moment of the muon.Comment: 29 pages, 7 figures. v2: discussion in sections 1 and 4 expanded,
  conclusions unchanged. Matches version published in JHE
On direct measurement of the W production charge asymmetry at the LHC

The prospects for making a direct measurement of the W production charge
asymmetry at the LHC are discussed. A modification to the method used at the
Tevatron is proposed for measurements at the LHC. The expected sensitivity for
such a measurement to parton distribution functions is compared to that for a
measurement of the lepton charge asymmetry. The direct measurement approach is
found to be less useful for placing constraints on parton distribution
functions at the LHC than a measurement of the lepton charge asymmetry.Comment: 18 pages, 10 figures, v2: references and keywords updated v3:
  Additional paragraph discussing inclusion of W asymmetry in global fits adde
Black holes in supergravity and integrability

Stationary black holes of massless supergravity theories are described by
certain geodesic curves on the target space that is obtained after dimensional
reduction over time. When the target space is a symmetric coset space we make
use of the group-theoretical structure to prove that the second order geodesic
equations are integrable in the sense of Liouville, by explicitly constructing
the correct amount of Hamiltonians in involution. This implies that the
Hamilton-Jacobi formalism can be applied, which proves that all such black hole
solutions, including non-extremal solutions, possess a description in terms of
a (fake) superpotential. Furthermore, we improve the existing integration
method by the construction of a Lax integration algorithm that integrates the
second order equations in one step instead of the usual two step procedure. We
illustrate this technology with a specific example.Comment: 44 pages, small typos correcte
See-saw neutrino masses and large mixing angles in the vortex background
  on a sphere

In the vortex background on a sphere, a single 6-dimensional fermion family
gives rise to 3 zero-modes in the 4-dimensional point of view, which may
explain the replication of families in the Standard Model. Previously, it had
been shown that realistic hierarchical mass and mixing patterns can be
reproduced for the quarks and the charged leptons. Here, we show that the
addition of a single heavy 6-dimensional field that is gauge singlet, unbound
to the vortex, and embedded with a bulk Majorana mass enables to generate 4D
Majorana masses for the light neutrinos through the see-saw mechanism. The
scheme is very predictive. The hierarchical structure of the fermion zero-modes
leads automatically to an inverted pseudo-Dirac mass pattern, and always
predicts one maximal angle in the neutrino see-saw matrix. It is possible to
obtain a second large mixing angle from either the charged lepton or the
neutrino sector, and we demonstrate that this model can fit all observed data
in neutrino oscillations experiments. Also, U_{e3} is found to be of the order
~0.1.Comment: 23 pages, 1 figur
Boundary entropy of supersymmetric Janus solutions

In this paper we compute the holographic boundary entropy for half-BPS Janus
deformations of the $AdS_3\times S^3\times T^4$ vacuum of type IIB
supergravity. Previous work \cite{Chiodaroli:2009yw} has shown that there are
two independent deformations of this sort. In one case, the six-dimensional
dilaton jumps across the interface, while the other case displays a jump of
axion and four-form potential. In case of a jump of the six-dimensional
dilaton, it is possible to compare the holographic result with the
weak-coupling result for a two-dimensional interface CFT where the radii of the
compactified bosons jump across the interface. We find exact agreement between
holographic and CFT results. This is to be contrasted with the holographic
calculation for the non-supersymmetric Janus solution, which agrees with the
CFT result only at the leading order in the jump parameter. We also examine the
implications of the holographic calculation in case of a solution with a jump
in the axion, which can be associated with a deformation of the CFT by the
$Z_2$-orbifold twist operator.Comment: 35 pages, pdf-LaTeX, 5 figures, v2: minor changes, typos corrected,
  reference adde
Giant QCD K-factors beyond NLO

Hadronic observables in Z+jet events can be subject to large NLO corrections
at TeV scales, with K-factors that even reach values of order 50 in some cases.
We develop a method, LoopSim, by which approximate NNLO predictions can be
obtained for such observables, supplementing NLO Z+jet and NLO Z+2-jet results
with a unitarity-based approximation for missing higher loop terms. We first
test the method against known NNLO results for Drell-Yan lepton pt spectra. We
then show our approximate NNLO results for the Z+jet observables. Finally we
examine whether the LoopSim method can provide useful information even in cases
without giant K-factors, with results for observables in dijet events that can
be compared to early LHC data.Comment: 38 pages, 13 figures; v2 includes additional reference
Light dark matter in the NMSSM: upper bounds on direct detection cross
  sections

In the Next-to-Minimal Supersymmetric Standard Model, a bino-like LSP can be
as light as a few GeV and satisfy WMAP constraints on the dark matter relic
density in the presence of a light CP-odd Higgs scalar. We study upper bounds
on the direct detection cross sections for such a light LSP in the mass range
2-20 GeV in the NMSSM, respecting all constraints from B-physics and LEP. The
OPAL constraints on e^+ e^- -> \chi^0_1 \chi^0_i (i > 1) play an important role
and are discussed in some detail. The resulting upper bounds on the
spin-independent and spin-dependent nucleon cross sections are ~ 10^{-42}
cm^{-2} and ~ 4\times 10^{-40} cm^{-2}, respectively. Hence the upper bound on
the spin-independent cross section is below the DAMA and CoGeNT regions, but
could be compatible with the two events observed by CDMS-II.Comment: 17 pages, 3 figure
Zero Sound in Strange Metallic Holography

One way to model the strange metal phase of certain materials is via a
holographic description in terms of probe D-branes in a Lifshitz spacetime,
characterised by a dynamical exponent z. The background geometry is dual to a
strongly-interacting quantum critical theory while the probe D-branes are dual
to a finite density of charge carriers that can exhibit the characteristic
properties of strange metals. We compute holographically the low-frequency and
low-momentum form of the charge density and current retarded Green's functions
in these systems for massless charge carriers. The results reveal a
quasi-particle excitation when z<2, which in analogy with Landau Fermi liquids
we call zero sound. The real part of the dispersion relation depends on
momentum k linearly, while the imaginary part goes as k^2/z. When z is greater
than or equal to 2 the zero sound is not a well-defined quasi-particle. We also
compute the frequency-dependent conductivity in arbitrary spacetime dimensions.
Using that as a measure of the charge current spectral function, we find that
the zero sound appears only when the spectral function consists of a single
delta function at zero frequency.Comment: 20 pages, v2 minor corrections, extended discussion in sections 5 and
  6, added one footnote and four references, version published in JHE
On the Existence of Meta-stable Vacua in Klebanov-Strassler

We solve for the complete space of linearized deformations of the
Klebanov-Strassler background consistent with the symmetries preserved by a
stack of anti-D3 branes smeared on the $S^3$ of the deformed conifold. We find
that the only solution whose UV physics is consistent with that of a
perturbation produced by anti-D3 branes must have a singularity in the
infrared, coming from NS and RR three-form field strengths whose energy density
diverges. If this singularity is admissible, our solution describes the
backreaction of the anti-D3 branes, and is thus likely to be dual to the
conjectured metastable vacuum in the Klebanov-Strassler field theory. If this
singularity is not admissible, then our analysis strongly suggests that anti-D3
branes do not give rise to metastable Klebanov-Strassler vacua, which would
have dramatic consequences for some string theory constructions of de Sitter
space. Key to this result is a simple, universal form for the force on a probe
D3-brane in our ansatz.Comment: 35 pages, LaTeX. v2: further details provided regarding the IR
  singularity and the discussion modified accordingly. typos corrected, refs
  adde
Theoretical and Phenomenological Constraints on Form Factors for
  Radiative and Semi-Leptonic B-Meson Decays

We study transition form factors for radiative and rare semi-leptonic B-meson
decays into light pseudoscalar or vector mesons, combining theoretical
constraints and phenomenological information from Lattice QCD, light-cone sum
rules, and dispersive bounds. We pay particular attention to form factor
parameterisations which are based on the so-called series expansion, and study
the related systematic uncertainties on a quantitative level. In this context,
we also provide the NLO corrections to the correlation function between two
flavour-changing tensor currents, which enters the unitarity constraints for
the coefficients in the series expansion.Comment: 52 pages; v2: normalization error in (29ff.) corrected, conclusion
  about relevance of unitarity bounds modified; form factor fits unaffected;
  references added; v3: discussion on truncation of series expansion added,
  matches version to be published in JHEP; v4: corrected typos in Tables 5 and