title: The nature of extremely red galaxies in the local universe

abstract:
  We investigate the nature of extremely red galaxies (ERGs), objects whose
colours are redder than those found in the red sequence present in
colour-magnitude diagrams of galaxies. We selected from the Sloan Digital Sky
Survey Data Release 7 a volume-limited sample of such galaxies in the redshift
interval 0.010 < z < 0.030, brighter than M_r = -17.8 (magnitudes dereddened,
corrected for the Milky Way extinction) and with (g-r) colours larger than
those of galaxies in the red sequence. This sample contains 416 ERGs, which
were classified visually. Our classification was cross-checked with other
classifications available in the literature. We found from our visual
classification that the majority of objects in our sample are edge-on spirals
(73%). Other spirals correspond to 13%, whereas elliptical galaxies comprise
only 11% of the objects. After comparing the morphological mix and the
distributions of H\alpha/H\beta and axial ratios of ERGs and objects in the red
sequence, we suggest that dust, more than stellar population effects, is the
driver of the red colours found in these extremely red galaxies.


title: A Hybrid Scheme for Heavy Flavors: Merging the FFNS and VFNS

abstract:
  We introduce a Hybrid Variable Flavor Number Scheme for heavy flavors,
denoted H-VFNS, which incorporates the advantages of both the traditional
Variable Flavor Number Scheme (VFNS) as well as the Fixed Flavor Number Scheme
(FFNS). By including an explicit $N_F$-dependence in both the Parton
Distribution Functions (PDFs) and the strong coupling constant $\alpha_S$, we
generate coexisting sets of PDFs and $\alpha_S$ for $N_F=\{3,4,5,6\}$ at any
scale $\mu$, that are related analytically by the $\overline{\text{MS}}$
matching conditions. The H-VFNS resums the heavy quark contributions and
provides the freedom to choose the optimal $N_F$ for each particular data set.
Thus, we can fit selected HERA data in a FFNS framework, while retaining the
benefits of the VFNS to analyze LHC data at high scales. We illustrate how such
a fit can be implemented for the case of both HERA and LHC data.


title: Physical interpretation of Kundt spacetimes using geodesic deviation

abstract:
  We investigate the fully general class of non-expanding, non-twisting and
shear-free D-dimensional geometries using the invariant form of geodesic
deviation equation which describes the relative motion of free test particles.
We show that the local effect of such gravitational fields on the particles
basically consists of isotropic motion caused by the cosmological constant
Lambda, Newtonian-type tidal deformations typical for spacetimes of algebraic
type D or II, longitudinal motion characteristic for spacetimes of type III,
and type N purely transverse effects of exact gravitational waves with D(D-3)/2
polarizations. We explicitly discuss the canonical forms of the geodesic
deviation motion in all algebraically special subtypes of the Kundt family for
which the optically privileged direction is a multiple Weyl aligned null
direction (WAND), namely D(a), D(b), D(c), D(d), III(a), III(b), IIIi, IIi,
II(a), II(b), II(c) and II(d). We demonstrate that the key invariant quantities
determining these algebraic types and subtypes also directly determine the
specific local motion of test particles, and are thus measurable by
gravitational detectors. As an example, we analyze an interesting class of type
N or II gravitational waves which propagate on backgrounds of type O or D,
including Minkowski, Bertotti-Robinson, Nariai and Plebanski-Hacyan universes.


title:
Augmented Superfield Approach to Nilpotent Symmetries in the Modified
  Version of 2D Proca Theory

abstract:
  We derive the complete set of off-shell nilpotent and absolutely
anticommuting Becchi-Rouet-Stora-Tyutin (BRST), anti-BRST and (anti-)co-BRST
symmetry transformations for all the fields of the modified version of two
(1+1)-dimensional (2D) Proca theory by exploiting the "augmented" superfield
formalism where the (dual-)horizontality conditions and (dual-)gauge-invariant
restrictions are exploited together. We capture the (anti-)BRST and
(anti-)co-BRST invariance of the Lagrangian density in the language of
superfield formalism. We also express the nilpotency and absolute
anticommutativity of the (anti-)BRST and (anti-)co-BRST charges within the
framework of augmented superfield formalism. This exercise leads to some novel
observations which have, hitherto, not been pointed out in the literature
within the framework of superfield approach to BRST formalism. For the sake of
completeness, we also mention, very briefly, a unique bosonic symmetry, the
ghost-scale symmetry and discrete symmetries of the theory and show that the
algebra of conserved charges captures the cohomological aspects of differential
geometry. Thus, our present modified 2D Proca theory is a model for the Hodge
Theory.


title: Escape, capture, and levitation of matter in Eddington outbursts

abstract:
  Context: An impulsive increase in luminosity by one half or more of the
Eddington value will lead to ejection of all optically thin plasma from
Keplerian orbits around the radiating star, if gravity is Newtonian and the
Poynting-Robertson drag is neglected. Radiation drag may bring some particles
down to the stellar surface. On the other hand, general relativistic
calculations show that gravity may be balanced by a sufficiently intense
radiation field at a certain distance from the star.
  Aims: We investigate the motion of test particles around highly luminous
stars to determine conditions under which plasma may be ejected from the
system.
  Results: In Einstein's gravity, if the outburst is close to the Eddington
luminosity, all test particles orbiting outside an "escape sphere" will be
ejected from the system, while all others will be captured from their orbits
onto the surface of another sphere, which is well above the stellar surface,
and may even be outside the escape sphere, depending on the value of
luminosity. Radiation drag will bring all the captured particles to rest on
this "Eddington capture sphere," where they will remain suspended in an
equilibrium state as long as the local flux of radiation does not change and
remains at the effective Eddington value.


title: Optimal Feature Selection in High-Dimensional Discriminant Analysis

abstract:
  We consider the high-dimensional discriminant analysis problem. For this
problem, different methods have been proposed and justified by establishing
exact convergence rates for the classification risk, as well as the l2
convergence results to the discriminative rule. However, sharp theoretical
analysis for the variable selection performance of these procedures have not
been established, even though model interpretation is of fundamental importance
in scientific data analysis. This paper bridges the gap by providing sharp
sufficient conditions for consistent variable selection using the sparse
discriminant analysis (Mai et al., 2012). Through careful analysis, we
establish rates of convergence that are significantly faster than the best
known results and admit an optimal scaling of the sample size n, dimensionality
p, and sparsity level s in the high-dimensional setting. Sufficient conditions
are complemented by the necessary information theoretic limits on the variable
selection problem in the context of high-dimensional discriminant analysis.
Exploiting a numerical equivalence result, our method also establish the
optimal results for the ROAD estimator (Fan et al., 2012) and the sparse
optimal scaling estimator (Clemmensen et al., 2011). Furthermore, we analyze an
exhaustive search procedure, whose performance serves as a benchmark, and show
that it is variable selection consistent under weaker conditions. Extensive
simulations demonstrating the sharpness of the bounds are also provided.


title: Magnetic-field asymmetry of nonlinear thermoelectric and heat transport

abstract:
  Nonlinear transport coefficients do not obey, in general, reciprocity
relations. We here discuss the magnetic-field asymmetries that arise in
thermoelectric and heat transport of mesoscopic systems. Based on a scattering
theory of weakly nonlinear transport, we analyze the leading-order symmetry
parameters in terms of the screening potential response to either voltage or
temperature shifts. We apply our general results to a quantum Hall antidot
system. Interestingly, we find that certain symmetry parameters show a
dependence on the measurement configuration.


title: Detonations in white dwarf dynamical interactions

abstract:
  In old, dense stellar systems collisions of white dwarfs are a rather
frequent phenomenon. Here we present the results of a comprehensive set of
Smoothed Particle Hydrodynamics simulations of close encounters of white dwarfs
aimed to explore the outcome of the interaction and the nature of the final
remnants for different initial conditions. Depending on the initial conditions
and the white dwarf masses, three different outcomes are possible.
Specifically, the outcome of the interaction can be either a direct or a
lateral collision or the interaction can result in the formation of an
eccentric binary system. In those cases in which a collision occurs, the
infalling material is compressed and heated such that the physical conditions
for a detonation may be reached during the most violent phases of the merger.
While we find that detonations occur in a significant number of our
simulations, in some of them the temperature increase in the shocked region
rapidly lifts degeneracy, leading to the quenching of the burning. We thus
characterize under which circumstances a detonation is likely to occur as a
result of the impact of the disrupted star on the surface of the more massive
white dwarf. Finally, we also study which interactions result in bound systems,
and in which ones the more massive white dwarf is also disrupted as a
consequence of the dynamical interaction. The sizable number of simulations
performed in this work allows to find how the outcome of the interaction
depends on the distance at closest approach, and on the masses of the colliding
white dwarfs, and which is the chemical pattern of the nuclearly processed
material. Finally, we also discuss the influence of the masses and core
chemical compositions of the interacting white dwarfs and the different kinds
of impact in the properties of the remnants.


title:
Nonzero solutions of perturbed Hammerstein integral equations with
  deviated arguments and applications

abstract:
  We provide a theory to establish the existence of nonzero solutions of
perturbed Hammerstein integral equations with deviated arguments, being our
main ingredient the theory of fixed point index. Our approach is fairly general
and covers a variety of cases. We apply our results to a periodic boundary
value problem with reflections and to a thermostat problem. In the case of
reflections we also discuss the optimality of some constants that occur in our
theory. Some examples are presented to illustrate the theory.


title: A Search for Boron in Damped Ly{\alpha} Systems

abstract:
  We present the first systematic study of boron beyond the Local Group. This
analysis is performed on a sample of 30 damped Ly{\alpha} systems (DLAs) with
strong metal-lines, which are expected to trace the interstellar medium of high
z galaxies. We report on two boron detections at > 3{\sigma} significance; one
new detection and one confirmation. The ratios of B/O and, for the first time,
B/S are compared with previous stellar and interstellar measurements in the
Milky Way and Small Magellanic Cloud. The novel comparison with sulphur, which
tracks oxygen's abundance, alleviates the uncertainty associated with stellar
oxygen measurements. For both detections, the inferred B/S ratio is in excess
of the prediction of primary boron production from spallation processes.
Possible sources of contamination are discussed, as well as physical effects
that could impact the observed ratios. However taken at face value, the
implication of these measurements suggest potentially higher cosmic ray fluxes
in DLAs. The prospects for future boron detections in other high redshift DLAs
to confirm our results is also discussed.


title: Forking in Short and Tame Abstract Elementary Classes

abstract:
  We develop a notion of forking for Galois-types in the context of Abstract
Elementary Classes (AECs). Under the hypotheses that an AEC $K$ is tame,
type-short, and failure of an order-property, we consider
  {\bf Definition.} Let $M_0 \prec N$ be models from $K$ and $A$ be a set. We
say that the Galois-type of $A$ over $M$ \emph{does not fork over $M_0$} iff
for all small $a \in A$ and all small $N^- \prec N$, we have that Galois-type
of $a$ over $N^-$ is realized in $M_0$.
  Assuming property (E) (see Definition 3.3) we show that this non-forking is a
well behaved notion of independence, in particular satisfies symmetry and
uniqueness and has a corresponding U-rank. We find conditions for a universal
local character, in particular derive superstability-like property from little
more than categoricity in a \big cardinal". Finally, we show that under large
cardinal axioms the proofs are simpler and the non-forking is more powerful. In
[BGKV] it is established that this notion of non-forking is the only
independence relation possible.


title:
Quantum phase transition between one-channel and two-channel Kondo
  polarons

abstract:
  For a mobile spin-1/2 impurity, coupled antiferromagnetically to a
one-dimensional gas of fermions, perturbative ideas have been used to argue in
favor of two-channel Kondo behavior of the impurity spin. Here we combine
general considerations and extensive numerical simulations to show that the
problem displays a novel quantum phase transition between two-channel and
one-channel Kondo screening upon increasing the Kondo coupling. We construct a
ground-state phase diagram and discuss the various non-trivial crossovers as
well as possible experimental realizations.


title:
The Fly's Eye Camera System -- an instrument design for large \'etendue
  time-domain survey

abstract:
  In this paper we briefly summarize the design concepts of the Fly's Eye
Camera System, a proposed high resolution all-sky monitoring device which
intends to perform high cadence time domain astronomy in multiple optical
passbands while still accomplish a high \'etendue. Fundings have already been
accepted by the Hungarian Academy of Sciences in order to design and build a
Fly's Eye device unit. Beyond the technical details and the actual scientific
goals, this paper also discusses the possibilities and yields of a network
operation involving ~10 sites distributed geographically in a nearly
homogeneous manner. Currently, we expect to finalize the mount assembly -- that
performs the sidereal tracking during the exposures -- until the end of 2012
and to have a working prototype with a reduced number of individual cameras
sometimes in the spring or summer of 2013.


title: The chemical case for no winds in dwarf irregular galaxies

abstract:
  We argue that isolated gas-rich dwarf galaxies -- in particular, dwarf
irregular (dIrr) galaxies -- do not necessarily undergo significant gas loss.
Our aim is to investigate whether the observed properties of isolated, gas-rich
dwarf galaxies, not affected by external environmental processes, can be
reproduced by self-consistent chemo-photometric infall models with continuous
star formation histories and no mass or metals loss. The model is characterized
by the total mass of primordial gas available to the object, its characteristic
collapse timescale, and a constant star formation efficiency. A grid of 144
such models has been computed by varying these parameters, and their
predictions (elemental abundances, stellar and gas masses, photometric colors)
have been compared with a set of observations of dIrr galaxies obtained from
the literature. It is found that the models with moderate to low efficiency are
able to reproduce most of the observational data, including the relative
abundances of nitrogen and oxygen.


title:
Three Problems Related to the Eigenvalues of Complex Non-central Wishart
  Matrices with a Rank-1 Mean

abstract:
  Recently, D. Wang has devised a new contour integral based method to simplify
certain matrix integrals. Capitalizing on that approach, we derive a new
expression for the probability density function (p.d.f.) of the joint
eigenvalues of a complex non-central Wishart matrix with a rank-1 mean. The
resulting functional form in turn enables us to use powerful classical
orthogonal polynomial techniques in solving three problems related to the
non-central Wishart matrix. To be specific, for an $n\times n$ complex
non-central Wishart matrix $\mathbf{W}$ with $m$ degrees of freedom ($m\geq n$)
and a rank-1 mean, we derive a new expression for the cumulative distribution
function (c.d.f.) of the minimum eigenvalue ($\lambda_{\min}$). The c.d.f. is
expressed as the determinant of a square matrix, the size of which depends only
on the difference $m-n$. This further facilitates the analysis of the
microscopic limit for the minimum eigenvalue which takes the form of the
determinant of a square matrix of size $m-n$ with the Bessel kernel. We also
develop a moment generating function based approach to derive the p.d.f. of the
random variable $\frac{\text{tr}(\mathbf{W})}{\lambda_{\min}}$, where
$\text{tr}(\cdot)$ denotes the trace of a square matrix. This random quantity
is of great importance in the so-called smoothed analysis of Demmel condition
number. Finally, we find the average of the reciprocal of the characteristic
polynomial $\det[z\mathbf{I}_n+\mathbf{W}],\; |\arg z|<\pi$, where
$\mathbf{I}_n$ and $\det[\cdot]$ denote the identity matrix of size $n$ and the
determinant, respectively.


title:
Constraining the atmosphere of GJ 1214b using an optimal estimation
  technique

abstract:
  We explore cloudy, extended H2-He atmosphere scenarios for the warm
super-Earth GJ 1214b using an optimal estimation retrieval technique. This
planet, orbiting an M4.5 star only 13 pc from the Earth, is of particular
interest because it lies between the Earth and Neptune in size and may be a
member of a new class of planet that is neither terrestrial nor gas giant. Its
relatively flat transmission spectrum has so far made atmospheric
characterisation difficult. The NEMESIS algorithm (Irwin et al. 2008) is used
to explore the degenerate model parameter space for a cloudy, H2-He-dominated
atmosphere scenario. Optimal estimation is a data-led approach that allows
solutions beyond the range permitted by ab initio equilibrium model atmosphere
calculations, and as such prevents restriction from prior expectations. We show
that optimal estimation retrieval is a powerful tool for this kind of study,
and present an exploration of the degenerate atmospheric scenarios for GJ
1214b. Whilst we find a family of solutions that provide a very good fit to the
data, the quality and coverage of these data are insufficient for us to more
precisely determine the abundances of cloud and trace gases given an H2-He
atmosphere, and we also cannot rule out the possibility of a high molecular
weight atmosphere. Future ground- and space-based observations will provide the
opportunity to confirm or rule out an extended H2-He atmosphere, but more
precise constraints will be limited by intrinsic degeneracies in the retrieval
problem, such as variations in cloud top pressure and temperature.


title:
Tricritical Point in Quantum Phase Transitions of the Coleman-Weinberg
  Model at Higgs Mass

abstract:
  The tricritical point, which separates first and second order phase
transitions in three-dimensional superconductors, is studied in the
four-dimensional Coleman-Weinberg model, and the similarities as well as the
differences with respect to the three-dimensional result are exhibited. The
position of the tricritical point in the Coleman-Weinberg model is derived and
found to be in agreement with the Thomas-Fermi approximation in the
three-dimensional Ginzburg-Landau theory. From this we deduce a special role of
the tricritical point for the Standard Model Higgs sector in the scope of the
latest experimental results, which suggests the unexpected relevance of
tricritical behavior in the electroweak interactions.


title:
Monotone gradient dynamics and location of stationary
  (p,q)-configurations

abstract:
  Exploiting the monotone property of the gradient dynamics of the
Frenkel-Kontorova model, we locate in the space of (p,q)-configurations the
ordered and unordered stationary states, as well as forbidden regions for such
states. Moreover we show that some generalized Frenkel--Kontorova models
(associated to multiharmonic standard maps) can have ordered
(p,q)--configurations that are neither action minimizing nor minimaximizing,
and give their location with respect to the set of (p,q)--minimizers and
minimaximizers.


title: Chaos at Fifty Four in 2013

abstract:
  In contrast to the claim of Motter and Campbell on Chaos at Fifty, done at
arXiv:1306.5777, it is pointed out that in 2013 we are at Chaos Fifty Four, if
to count correctly and to remember about pioneering results of Boris Chirikov
obtained in 1959.


title:
Time-dependent density functional theory for X-ray near-edge
  spectroscopy

abstract:
  We derive a time-dependent density functional theory appropriate for
calculating the near-edge X-ray absorption spectrum in molecules and condensed
matter. The basic assumption is to increase the space of many-body wave
functions from one Slater determinant to two. The equations of motion derived
from Dirac's variational principle provide an exact solution for the linear
response when the interaction Hamiltonian has only a core-electron field. The
equations can be solved numerically nearly as easily as the ordinary real-time
time-dependent Kohn-Sham equations. We carry out the solution under conditions
that permit comparison with the expected power-law behavior. Our extracted
power-law exponents are similar to those derived by Nozieres and DeDominicis,
but are not in quantitative agreement. We argue that our calculational method
can be readily generalized to density functionals that take into account the
more general electron-electron interactions that are needed for treating
dynamic effects such as plasmon excitations.


title:
Stochastic Optimal Control as Non-equilibrium Statistical Mechanics:
  Calculus of Variations over Density and Current

abstract:
  In Stochastic Optimal Control (SOC) one minimizes the average cost-to-go,
that consists of the cost-of-control (amount of efforts), cost-of-space (where
one wants the system to be) and the target cost (where one wants the system to
arrive), for a system participating in forced and controlled Langevin dynamics.
We extend the SOC problem by introducing an additional cost-of-dynamics,
characterized by a vector potential. We propose derivation of the generalized
gauge-invariant Hamilton-Jacobi-Bellman equation as a variation over density
and current, suggest hydrodynamic interpretation and discuss examples, e.g.,
ergodic control of a particle-within-a-circle, illustrating non-equilibrium
space-time complexity.

categories: cond-mat.stat-mech cs.SY math-ph math.MP math.OC


title: Plethora of q-oscillators possessing pairwise energy level degeneracy

abstract:
  Using the q,p-deformed oscillators as basic generating system, we obtain
diverse classes (which form distinct sectors of functional continua) of novel
versions of q-deformed oscillators, all of which share the property of
"accidental" degeneracy within a fixed pair of energy levels E_{m} = E_{m+1},
m\ge 1, occurring at the real deformation parameter fixed by an appropriate
value q(m) that depends on m and on particular model. Likewise, the degeneracy
E_{0} = E_{k} (where k\ge 2) takes place, for properly fixed q=q(k), in most of
those models. The formerly studied model of q-oscillator known as the
Tamm-Dancoff cutoff deformed oscillator is contained in the continua as
isolated special case.


title: On Corrections to the Born-Oppenheimer Approximation

abstract:
  This report presents a new approach for treating the coupling of electrons
and nuclei in quantum mechanical calculations for molecules and condensed
matter. It includes the standard "Born-Oppenheimer approximation" as a special
case but treats both adiabatic and non-adiabatic corrections using perturbation
theory. The adiabatic corrections include all terms that do not explicitly
involve the nuclear wavefunctions, so that the nuclei move on a single
electronic potential surface. The non-adiabatic corrections, which allow the
nuclei to move on more than one potential surface, include coupling between the
electronic and nuclear wavefunctions. The method is related to an approach
first proposed by Born and Huang, but it differs in the methodology and in the
definition of the electronic wavefunctions and potential surfaces. A simple
example is worked out to illustrate the mechanics of the technique. The report
also includes a review of previous work.


title: Scattering Equations and KLT Orthogonality

abstract:
  Several recent developments point to the fact that rational maps from
n-punctured spheres to the null cone of D dimensional momentum space provide a
natural language for describing the scattering of massless particles in D
dimensions. In this note we identify and study equations relating the kinematic
invariants and the puncture locations, which we call the scattering equations.
We provide an inductive algorithm in the number of particles for their
solutions and prove a remarkable property which we call KLT Orthogonality. In a
nutshell, KLT orthogonality means that "Parke-Taylor" vectors constructed from
the solutions to the scattering equations are mutually orthogonal with respect
to the Kawai-Lewellen-Tye (KLT) bilinear form. We end with comments on possible
connections to gauge theory and gravity amplitudes in any dimension and to the
high-energy limit of string theory amplitudes.


title: On the largest Lyapunov exponent for products of Gaussian matrices

abstract:
  The paper provides a new integral formula for the largest Lyapunov exponent
of Gaussian matrices, which is valid in the real, complex and quaternion-valued
cases. This formula is applied to derive asymptotic expressions for the largest
Lyapunov exponent when the size of the matrix is large and compare the Lyapunov
exponents in models with a spike and no spikes.


title: An Equation of State for Helium

abstract:
  This report describes a new equation of state (EOS) for helium. The PANDA
code was used to construct separate EOS tables for the solid and fluid phases.
The solid and fluid EOS were then assembled into a multiphase EOS table using
the PANDA phase transition option. Contributions from thermal electronic
excitation and ionization were also included in the model. The EOS gives very
good agreement with all static and shock-wave data, except at temperatures
below 20K, where further work is needed. This EOS was developed primarily for
use in models of the giant planets, the sun, and stars but should be useful in
other applications as well.


title: Multiphysics simulation of corona discharge induced ionic wind

abstract:
  Ionic wind devices or electrostatic fluid accelerators are becoming of
increasing interest as tools for thermal management, in particular for
semiconductor devices. In this work, we present a numerical model for
predicting the performance of such devices, whose main benefit is the ability
to accurately predict the amount of charge injected at the corona electrode.
Our multiphysics numerical model consists of a highly nonlinear strongly
coupled set of PDEs including the Navier-Stokes equations for fluid flow,
Poisson's equation for electrostatic potential, charge continuity and heat
transfer equations. To solve this system we employ a staggered solution
algorithm that generalizes Gummel's algorithm for charge transport in
semiconductors. Predictions of our simulations are validated by comparison with
experimental measurements and are shown to closely match. Finally, our
simulation tool is used to estimate the effectiveness of the design of an
electrohydrodynamic cooling apparatus for power electronics applications.


title:
Matter Wave Interferometry of a Levitated Thermal Nano-Oscillator
  Induced and Probed by a Spin

abstract:
  We show how the interference between spatially separated states of the center
of mass (COM) of a mesoscopic harmonic oscillator can be evidenced by coupling
it to a spin and performing solely spin manipulations and measurements (Ramsey
Interferometry). We propose to use an optically levitated diamond bead
containing an NV center spin. The nano-scale size of the bead makes the
motional decoherence due to levitation negligible. The form of the spin-motion
coupling ensures that the scheme works for thermal states so that moderate
feedback cooling suffices. No separate control or observation of the COM state
is required and thereby one dispenses with cavities, spatially resolved
detection and low mass-dispersion ensembles. The controllable relative phase in
the Ramsey interferometry stems from a gravitational potential difference so
that it uniquely evidences coherence between states which involve the whole
nano-crystal being in spatially distinct locations.


title: Tautological relations in moduli spaces of weighted pointed curves

abstract:
  Pandharipande-Pixton have used the geometry of the moduli space of stable
quotients to produce relations between tautological Chow classes on the moduli
space $M_g$ of smooth genus g curves. We study a natural extension of their
methods to the boundary and more generally to Hassett's moduli spaces
$\overline M_{g, w}$ of stable nodal curves with weighted marked points.
Algebraic manipulation of these relations brings them into a Faber-Zagier type
form. We show that they give Pixton's generalized FZ relations when all weights
are one. As a special case, we give a formulation of FZ relations for the
n-fold product of the universal curve over $M_g$.


title:
Funciones Esf\'ericas Matriciales Asociadas a las Esferas y a los
  Espacios Proyectivos Reales

abstract:
  In this work we start by determining all irreducible spherical functions
$\Phi$ of any $K $-type associated to the pair $(G,K)=(\SO(4),\SO(3))$. The
functions $P=P(u)$ corresponding to the irreducible spherical functions of a
fixed $K$-type $\pi_\ell$ are appropriately packaged into a sequence of matrix
valued polynomials $(P_w)_{w\ge0}$ of size $(\ell+1)\times(\ell+1)$. Finally we
prove that $\widetilde P_w={P_0}^{-1}P_w$ is a sequence of matrix orthogonal
polynomials with respect to a weight matrix $W$. Moreover, we show that $W$
admits a second order symmetric hypergeometric operator $\widetilde D$ and a
first order symmetric differential operator $\widetilde E$.
  Later, we establish a direct relationship between the spherical functions of
the $n$-dimensional sphere $S^n\simeq\SO(n+1)/\SO(n)$ and the spherical
functions of the $n$-dimensional real projective space
$P^n(\mathbb{R})\simeq\SO(n+1)/\mathrm{O}(n)$. Concluding that to find all the
spherical functions of one of these pairs is equivalent to do the same it with
the other.
  Finally, we study the spherical functions of certain types of the
$n$-dimensional sphere $S^{n}\simeq \SO(n+1)/\SO(n)$, for any $n$. More
precisely, we give explicitly all the spherical functions whose associated
functions $H$ are scalar valued, including those of trivial type, and then we
study the irreducible spherical functions of fundamental type, describing them
in terms of matrix valued hypergeometric functions $_2!F_1$. Thereafter, for
every fundamental type we build a sequence of ortogonal matrix valued
polynomials with respect to a weight $W$, which are associated to the spherical
functions. We also prove that, for any $n$, $W$ admits a second order symmetric
differential operator.


title: Ekpyrotic loop quantum cosmology

abstract:
  We consider the ekpyrotic paradigm in the context of loop quantum cosmology.
In loop quantum cosmology the classical big-bang singularity is resolved due to
quantum gravity effects, and so the contracting ekpyrotic branch of the
universe and its later expanding phase are connected by a smooth bounce. Thus,
it is possible to explicitly determine the evolution of scalar perturbations,
from the contracting ekpyrotic phase through the bounce and to the post-bounce
expanding epoch. The possibilities of having either one or two scalar fields
have been suggested for the ekpyrotic universe, and both cases will be
considered here. In the case of a single scalar field, the constant mode of the
curvature perturbations after the bounce is found to have a blue spectrum. On
the other hand, for the two scalar field ekpyrotic model where scale-invariant
entropy perturbations source additional terms in the curvature perturbations,
the power spectrum in the post-bounce expanding cosmology is shown to be nearly
scale-invariant and so agrees with observations.


title:
A note on Keen's model: The limits of Schumpeter's "Creative
  Destruction"

abstract:
  This paper presents a general solution for a recent model by Keen for
endogenous money creation. The solution provides an analytic framework that
explains all significant dynamical features of Keen's model and their
parametric dependence, including an exact result for both the period and
subsidence rate of the Great Moderation. It emerges that Keen's model has just
two possible long term solutions: stable growth or terminal collapse. While
collapse can come about immediately from economies that are nonviable by virtue
of unsuitable parameters or initial conditions, in general the collapse is
preceded by an interval of exponential growth. In first approximation, the
duration of that exponential growth is half a period of a sinusoidal
oscillation. The period is determined by reciprocal of the imaginary part of
one root of a certain quintic polynomial. The real part of the same root
determines the rate of growth of the economy. The coefficients of that
polynomial depend in a complicated way upon the numerous parameters in the
problem and so, therefore, the pattern of roots. For a favorable choice of
parameters, the salient root is purely real. This is the circumstance that
admits the second possible long term solution, that of indefinite stable
growth, i.e. an infinite period.


title:
An introduction to the coverage of the Data Citation Index
  (Thomson-Reuters): disciplines, document types and repositories

abstract:
  In the past years, the movement of data sharing has been enjoying great
popularity. Within this context, Thomson Reuters launched at the end of 2012 a
new product inside the Web of Knowledge family: the Data Citation Index. The
aim of this tool is to enable discovery and access, from a single place, to
data from a variety of data repositories from different subject areas and from
around the world. In this short note we present some preliminary results from
the analysis of the Data Citation Index. Specifically, we address the following
issues: discipline coverage, data types present in the database, and
repositories that were included at the time of the study


title:
Dynamics of the fast component of nano-confined water under electric
  field

abstract:
  We report the diffusion of water molecules confined in the pores of folded
silica materials (FSM-12 with average pore diameter of $\sim$ 16 \AA), measured
by means of quasielastic neutron scattering using the cold neutron chopper
spectrometer (CNCS). The goal is to investigate the effect of electric field on
the previously observed fast component of nano-confined water. The measurements
were taken at temperatures between 220 K and 245 K, and at two electric field
values, 0 kV/mm and 2 kV/mm. Similar to the recently observed electric field
induced enhancement of the slow translational motion of confined water, there
is a an equally important impact of the field on the faster diffusion.


title:
The impact of the phase-space density on the indirect detection of dark
  matter

abstract:
  We study the indirect detection of dark matter when the local dark matter
velocity distribution depends upon position, as expected for the Milky Way and
its dwarf spheroidal satellites, and the annihilation cross-section is not
purely s-wave. Using a phase-space distribution consistent with the dark matter
density profile, we present estimates of cosmic and gamma-ray fluxes from dark
matter annihilations. The expectations for the indirect detection of dark
matter can differ significantly from the usual calculation that assumes that
the velocity of the dark matter particles follows a Maxwell-Boltzmann
distribution.


title: SPH-based simulation of multi-material asteroid collisions

abstract:
  We give a brief introduction to smoothed particle hydrodynamics methods for
continuum mechanics. Specifically, we present our 3D SPH code to simulate and
analyze collisions of asteroids consisting of two types of material: basaltic
rock and ice. We consider effects like brittle failure, fragmentation, and
merging in different impact scenarios. After validating our code against
previously published results we present first collision results based on
measured values for the Weibull flaw distribution parameters of basalt.


title: Moderate deviations for importance sampling estimators of risk measures

abstract:
  Importance sampling has become an important tool for the computation of
tail-based risk measures. Since such quantities are often determined mainly by
rare events standard Monte Carlo can be inefficient and importance sampling
provides a way to speed up computations. This paper considers moderate
deviations for the weighted empirical process, the process analogue of the
weighted empirical measure, arising in importance sampling. The moderate
deviation principle is established as an extension of existing results. Using a
delta method for large deviations established by Gao and Zhao (Ann. Statist.,
2011) together with classical large deviation techniques, the moderate
deviation principle for the weighted empirical process is extended to
functionals of the weighted empirical process which correspond to risk
measures. The main results are moderate deviation principles for importance
sampling estimators of the quantile function of a distribution and Expected
Shortfall.


title: Dirac reduction for Poisson vertex algebras

abstract:
  We construct an analogue of Dirac's reduction for an arbitrary local or
non-local Poisson bracket in the general setup of non-local Poisson vertex
algebras. This leads to Dirac's reduction of an arbitrary non-local Poisson
structure. We apply this construction to an example of a generalized
Drinfeld-Sokolov hierarchy.


title: Exchange interaction and its tuning in magnetic binary chalcogenides

abstract:
  Using a first-principles Green's function approach we study magnetic
properties of the magnetic binary chalcogenides Bi2Te3, Bi2Se3, and Sb2Te3. The
magnetic coupling between transition-metal impurities is long-range, extends
beyond a quintuple layer, and decreases with increasing number of d electrons
per 3d atom. We find two main mechanisms for the magnetic interaction in these
materials: the indirect exchange interaction mediated by free carriers and the
indirect interaction between magnetic moments via chalcogen atoms. The
calculated Curie temperatures of these systems are in good agreement with
available experimental data. Our results provide deep insight into magnetic
interactions in magnetic binary chalcogenides and open a way to design new
materials for promising applications.


title: Variational thermodynamics of relativistic thin disks

abstract:
  We present a relativistic model describing a thin disk system composed of two
fluids. The system is surrounded by a halo in the presence of a non-trivial
electromagnetic field. We show that the model is compatible with the
variational multi-fluid thermodynamics formalism, allowing us to determine all
the thermodynamic variables associated with the matter content of the disk. The
asymptotic behaviour of these quantities indicates that the single fluid
interpretation should be abandoned in favour of a two-fluid model.


title: On classical finite and affine W-algebras

abstract:
  This paper is meant to be a short review and summary of recent results on the
structure of finite and affine classical W-algebras, and the application of the
latter to the theory of generalized Drinfeld-Sokolov hierarchies.


title:
Network Sparsification for Steiner Problems on Planar and Bounded-Genus
  Graphs

abstract:
  We propose polynomial-time algorithms that sparsify planar and bounded-genus
graphs while preserving optimal or near-optimal solutions to Steiner problems.
Our main contribution is a polynomial-time algorithm that, given an unweighted
graph $G$ embedded on a surface of genus $g$ and a designated face $f$ bounded
by a simple cycle of length $k$, uncovers a set $F \subseteq E(G)$ of size
polynomial in $g$ and $k$ that contains an optimal Steiner tree for any set of
terminals that is a subset of the vertices of $f$.
  We apply this general theorem to prove that: * given an unweighted graph $G$
embedded on a surface of genus $g$ and a terminal set $S \subseteq V(G)$, one
can in polynomial time find a set $F \subseteq E(G)$ that contains an optimal
Steiner tree $T$ for $S$ and that has size polynomial in $g$ and $|E(T)|$; * an
analogous result holds for an optimal Steiner forest for a set $S$ of terminal
pairs; * given an unweighted planar graph $G$ and a terminal set $S \subseteq
V(G)$, one can in polynomial time find a set $F \subseteq E(G)$ that contains
an optimal (edge) multiway cut $C$ separating $S$ and that has size polynomial
in $|C|$.
  In the language of parameterized complexity, these results imply the first
polynomial kernels for Steiner Tree and Steiner Forest on planar and
bounded-genus graphs (parameterized by the size of the tree and forest,
respectively) and for (Edge) Multiway Cut on planar graphs (parameterized by
the size of the cutset). Additionally, we obtain a weighted variant of our main
contribution.


title:
Signature of an $h_1$ state in the $J/\psi \to \eta h_1 \to \eta
  K^{*0}\bar{K}^{*0}$ decay

abstract:
  The BES data on the $J/\psi \to \eta K^{*0}\bar{K}^{*0}$ reaction show a
clear enhancement in the $K^{*0}\bar{K}^{*0}$ mass distribution close to the
threshold of this channel. Such an enhancement is usually a signature of a L=0
resonance around threshold, which in this case would correspond to an $h_1$
state with quantum numbers $I^G(J^{PC})=0^-(1^{+-})$. A state around $1800\
\text{MeV}$ results from the interaction of the $K^* \bar{K}^*$ using the local
hidden gauge approach. We show that the peak observed in $J/\psi \to \eta
K^{*0}\bar{K}^{*0}$ naturally comes from the creation of this $h_1$ state with
mass and width around $1830\ \text{MeV}$ and $110\ \text{MeV}$, respectively. A
second analysis, model independent, corroborates the first result, confirming
the relationship of the enhancement in the invariant mass spectrum with the
$h_1$ resonance.


title: Altmetrics: New Indicators for Scientific Communication in Web 2.0

abstract:
  In this paper we review the socalled altmetrics or alternative metrics. This
concept raises from the development of new indicators based on Web 2.0, for the
evaluation of the research and academic activity. The basic assumption is that
variables such as mentions in blogs, number of twits or of researchers
bookmarking a research paper for instance, may be legitimate indicators for
measuring the use and impact of scientific publications. In this sense, these
indicators are currently the focus of the bibliometric community and are being
discussed and debated. We describe the main platforms and indicators and we
analyze as a sample the Spanish research output in Communication Studies.
Comparing traditional indicators such as citations with these new indicators.
The results show that the most cited papers are also the ones with a highest
impact according to the altmetrics. We conclude pointing out the main
shortcomings these metrics present and the role they may play when measuring
the research impact through 2.0 platforms.


title:
Self-assembly of catalytically active colloidal molecules: Tailoring
  activity through surface chemistry

abstract:
  A heterogeneous and dilute suspension of catalytically active colloids is
studied as a non-equilibrium analogue of ionic systems, which has the
remarkable feature of action-reaction symmetry breaking. Symmetrically coated
colloids are found to join up to form self-assembled molecules that could be
inert or have spontaneous activity in the form of net translational velocity
and spin depending on their symmetry properties and their constituents. The
type of activity can be adjusted by changing the surface chemistry and ambient
variables that control the surface reactions and the phoretic drift.


title:
Earthquake Disaster based Efficient Resource Utilization Technique in
  IaaS Cloud

abstract:
  Cloud Computing is an emerging area. The main aim of the initial
search-and-rescue period after strong earthquakes is to reduce the whole number
of mortalities. One main trouble rising in this period is to and the greatest
assignment of available resources to functioning zones. For this issue a
dynamic optimization model is presented. The model uses thorough descriptions
of the operational zones and of the available resources to determine the
resource performance and efficiency for different workloads related to the
response. A suitable solution method for the model is offered as well. In this
paper, Earthquake Disaster Based Resource Scheduling (EDBRS) Framework has been
proposed. The allocation of resources to cloud workloads based on urgency
(emergency during Earthquake Disaster). Based on this criterion, the resource
scheduling algorithm has been proposed. The performance of the proposed
algorithm has been assessed with the existing common scheduling algorithms
through the CloudSim. The experimental results show that the proposed algorithm
outperforms the existing algorithms by reducing execution cost and time of
cloud consumer workloads submitted to the cloud.


title:
A More Complicated Hardness Proof for Finding Densest Subgraphs in
  Bounded Degree Graphs

abstract:
  We consider the Densest-Subgraph problem, where a graph and an integer k is
given and we search for a subgraph on exactly k vertices that induces the
maximum number of edges. We prove that this problem is NP-hard even when the
input graph has maximum degree three.


title: Vector Polynomials and a Matrix Weight Associated to Dihedral Groups

abstract:
  The space of polynomials in two real variables with values in a 2-dimensional
irreducible module of a dihedral group is studied as a standard module for
Dunkl operators. The one-parameter case is considered (omitting the
two-parameter case for even dihedral groups). The matrix weight function for
the Gaussian form is found explicitly by solving a boundary value problem, and
then computing the normalizing constant. An orthogonal basis for the
homogeneous harmonic polynomials is constructed. The coefficients of these
polynomials are found to be balanced terminating $_4F_3$-series.


title:
Semiclassical description of resonance-assisted tunneling in
  one-dimensional integrable models

abstract:
  Resonance-assisted tunneling is investigated within the framework of
one-dimensional integrable systems. We present a systematic recipe, based on
Hamiltonian normal forms, to construct one-dimensional integrable models that
exhibit resonance island chain structures with accurately controlled sizes and
positions of the islands. Using complex classical trajectories that evolve
along suitably defined paths in the complex time domain, we construct a
semiclassical theory of the resonance-assisted tunneling process. This
semiclassical approach yields a compact analytical expression for
tunneling-induced level splittings which is found to be in very good agreement
with the exact splittings obtained through numerical diagonalisation.


title:
Stable Determination of Time-Dependent Scalar Potential From Boundary
  Measurements in a Periodic Quantum Waveguide

abstract:
  We prove logarithmic stability in the determination of the time-dependent
scalar potential in a 1-periodic quantum cylindrical waveguide, from the
boundary measurements of the solution to the dynamic Schr\"odinger equation.


title: On the Continuum Time Limit of Reaction-Diffusion Systems

abstract:
  The parity conserving branching-annihilating random walk (pc-BARW) model is a
reaction-diffusion system on a lattice where particles can branch into $m$
offsprings with even $m$ and hop to neighboring sites. If two or more particles
land on the same site, they immediately annihilate pairwise. In this way the
number of particles is preserved modulo two. It is well known that the pc-BARW
with $m=2$ in 1 spatial dimension has no phase transition (it is always
subcritical), if the hopping is described by a continuous time random walk. In
contrast, the $m=2$ 1-d pc-BARW has a phase transition when formulated in
discrete time, but we show that the continuous time limit is non-trivial: When
the time step $\delta t\to 0$, the branching and hopping probabilities at the
critical point scale with different powers of $\delta t$. These powers are
different for different microscopic realizations. Although this phenomenon is
not observed in some other reaction-diffusion systems like, e.g. the contact
process, we argue that it should be generic and not restricted to the 1-d
pc-BARW model.


title:
Parametric amplification of the mechanical vibrations of a suspended
  nanowire by magnetic coupling to a Bose-Einstein condensate

abstract:
  We consider the possibility of parametric amplification of a mechanical
vibration mode of a nanowire due to its interaction with a Bose-Einstein
condensate (BEC) of ultracold atoms. The magneto-mechanical coupling is
mediated by the vibrationally modulated magnetic field around the
current-carrying nanowire, which can induce atomic transitions between
different hyperfine sublevels. We theoretically analyze the limitations arising
from the fact that the spin inverted atomic medium which feeds the mechanical
oscillation has a finite bandwidth in the range of the chemical potential of
the condensate.


title: Jet Cross-Section Measurements In CMS

abstract:
  The Large Hadron Collider (LHC) experiment has successfully completed data
taking at center of mass (COM) energy 7 TeV in 2011 and very recently for 8
TeV. Measurement of cross sections predicted by the standard model were the
main tasks in the beginning. The inclusive jet cross section and dijet mass
measurement is already done at 7 TeV energy by Compact Muon Solenoid (CMS)
detector with integrated luminosity 5 fb$^{-1}$. In these measurement one needs
to understand and measure precisely the kinematic properties of jets which
involve many theoretical and experimental issues. The goal of this article is
to discuss all these issues including jet measurements in CMS and subsequently
review the inclusive jet cross section and dijet mass measurement in CMS at 7
TeV with integrated luminosity 5 fb$^{-1}$. The measurements, after unfolding
the data, are also compared with the next leading order (NLO) theory
predictions, corrected for the non-perturbative (NP) effects, for five
different sets of parton distribution functions (PDF). It is observed that the
measurements, for both cases, agree with the theory prediction within
$\sim$8-10% depending on transverse momentum ($p_T$) and dijet invariant mass
($M_{jj}$) of jets.


title: Combinatorial Hopf algebra structure on packed square matrices

abstract:
  We construct a new bigraded Hopf algebra whose bases are indexed by square
matrices with entries in the alphabet $\{0, 1, ..., k\}$, $k \geq 1$, without
null rows or columns. This Hopf algebra generalizes the one of permutations of
Malvenuto and Reutenauer, the one of $k$-colored permutations of Novelli and
Thibon, and the one of uniform block permutations of Aguiar and Orellana. We
study the algebraic structure of our Hopf algebra and show, by exhibiting
multiplicative bases, that it is free. We moreover show that it is self-dual
and admits a bidendriform bialgebra structure. Besides, as a Hopf subalgebra,
we obtain a new one indexed by alternating sign matrices. We study some of its
properties and algebraic quotients defined through alternating sign matrices
statistics.


title:
Interactions between teaching assistants and students boost engagement
  in physics labs

abstract:
  Through in-class observations of teaching assistants (TAs) and students in
the lab sections of a large introductory physics course, we study which TA
behaviors can be used to predict student engagement and, in turn, how this
engagement relates to learning. For the TAs, we record data to determine how
they adhere to and deliver the lesson plan and how they interact with students
during the lab. For the students, we use observations to record the level of
student engagement and pre- and post-tests of lab skills to measure learning.
We find that the frequency of TA-student interactions, especially those
initiated by the TAs, is a positive and significant predictor of student
engagement. Interestingly, the length of interactions is not significantly
correlated with student engagement. In addition, we find that student
engagement was a better predictor of post-test performance than pre-test
scores. These results shed light on the manner in which students learn how to
conduct inquiry and suggest that, by proactively engaging students, TAs may
have a positive effect on student engagement, and therefore learning, in the
lab.


title:
Dissipative Bohmian mechanics within the Caldirola-Kanai framework: A
  trajectory analysis of wave-packet dynamics in viscid media

abstract:
  Classical viscid media are quite common in our everyday life. However, we are
not used to find such media in quantum mechanics, and much less to analyze
their effects on the dynamics of quantum systems. In this regard, the
Caldirola-Kanai time-dependent Hamiltonian constitutes an appealing model,
accounting for friction without including environmental fluctuations (as it
happens, for example, with quantum Brownian motion). Here, a Bohmian analysis
of the associated friction dynamics is provided in order to understand how a
hypothetical, purely quantum viscid medium would act on a wave packet from a
(quantum) hydrodynamic viewpoint. To this purpose, a series of paradigmatic
contexts have been chosen, such as the free particle, the motion under the
action of a linear potential, the harmonic oscillator, or the superposition of
two coherent wave packets. Apart from their analyticity, these examples
illustrate interesting emerging behaviors, such as localization by "quantum
freezing" or a particular type of quantum-classical correspondence. The
reliability of the results analytically determined has been checked by means of
numerical simulations, which has served to investigate other problems lacking
of such analyticity (e.g., the coherent superpositions).


title:
Bounds on the volume of an inclusion in a body from a complex
  conductivity measurement

abstract:
  We derive bounds on the volume of an inclusion in a body in two or three
dimensions when the conductivities of the inclusion and the surrounding body
are complex and assumed to be known. The bounds are derived in terms of average
values of the electric field, current, and certain products of the electric
field and current. All of these average values are computed from a single
electrical impedance tomography measurement of the voltage and current on the
boundary of the body. Additionally, the bounds are tight in the sense that at
least one of the bounds gives the exact volume of the inclusion for certain
geometries and boundary conditions.


title: T-Duality in Gauged Linear Sigma-Models with Torsion

abstract:
  (0,2) gauged linear sigma models with torsion, corresponding to principal
torus bundles over warped CY bases, provide a useful framework for getting
exact statements about perturbative dualities in the presence of fluxes. In
this context we first study dualities mapping the torus fiber onto itself,
implying the existence of quantization constraints on the torus moduli for
consistency. Second, we investigate dualities mixing the principal torus bundle
with the gauge bundle, relating the torsional GLSMs to ordinary ones
corresponding to CY compactifications with non-standard embeddings, namely two
classes of models with different target-space topologies.


title: Meron Ground State of Rashba Spin-Orbit-Coupled Dipolar Bosons

abstract:
  We study the effects of dipolar interactions on a Bose-Einstein condensate
with synthetically generated Rashba spin-orbit coupling. The dipolar
interaction we consider includes terms that couple spin and orbital angular
momentum in a way perfectly congruent with the single-particle Rashba coupling.
We show that this internal spin-orbit coupling plays a crucial role in the rich
ground-state phase diagram of the trapped condensate. In particular, we predict
the emergence of a thermodynamically stable ground state with a meron spin
configuration.


title: Physics with Charmonium -- A few recent highlights of BESIII

abstract:
  Despite the successes of the standard model, the non-perturbative dynamics of
the strong interaction are not fully understood yet. Charmonium spectroscopy
serves as an ideal tool to shed light on the dynamics of the strong interaction
such as quark confinement and the generation of hadron masses. The BESIII
collaboration studies extensively the strong interaction and various aspects
that could shed light on physics beyond the standard model via copious
e$^+$e$^-$ collisions at the BESIII/BEPCII facility in Beijing, China, in the
charmonium mass regime. I present a few of the recent results with the emphasis
on charmonium spectroscopy and decay studies using 106$\times10^6$ $\psi(3686)$
events.


title: Semi-holographic model revisited

abstract:
  In a recent work Zhang, Li and Noh [Phys. Lett. B {\bf 694}, 177
(2010)]proposed a model for dark energy assuming this component strictly obeys
the holographic principle. They performed a dynamical system analysis, finding
a scaling solution which is helpful to solve the coincidence problem. However
they need explicitly a cosmological constant. In this paper we derive an
explicit analytical solution, without $\Lambda$, that shows agreement with the
Supernovae data. However this solution is not physical because violate all the
energy conditions.


title: Closed flat Riemannian 4-manifolds

abstract:
  In this paper we describe the classification of all the geometric fibrations
of a closed flat Riemannian 4-manifold over a 1-orbifold.


title:
Analytic Wavefunctions for Neutral Bulk Excitations in Fractional
  Quantum Hall Fluids

abstract:
  We show the model wavefunctions for the neutral collective modes in
fractional quantum Hall (FQH) states have simple analytic forms obtained from
judicially reducing the powers of selected pairs in the ground state Jastrow
factor. This scheme of "pair excitations" works for the magneto-roton modes of
single-component Abelian and non-Abeliean FQH states, as well as the neutral
fermion mode for the Moore-Read (MR) state. The analytic wavefunctions allow us
to compute the "quadrupole gap" of the magneto-roton mode in the thermodynamic
limit, which was previously inaccessible to the numerics. The quadrupole gap is
related to the fusion of the charges in the two-dimensional plasma picture,
extending the plasma analogy to neutral excitations. A lattice diagrammatic
method of representing these many-body wavefunctions and FQH elementary
excitations is also presented.


title:
Explicit error bound for modified numerical iterated integration by
  means of Sinc methods

abstract:
  This paper reinforces numerical iterated integration developed by
Muhammad--Mori in the following two points: 1) the approximation formula is
modified so that it can achieve a better convergence rate in more general
cases, and 2) explicit error bound is given in a computable form for the
modified formula. The formula works quite efficiently, especially if the
integrand is of a product type. Numerical examples that confirm it are also
presented.


title: $\Psi$ and $\Upsilon$ Production In pp Collisions at 7.0 TeV

abstract:
  This is an extension of recent studies [arXiv:1207.3296] for $\Upsilon(nS)$
and $\Psi(1S,2S)$ production at the LHC in pp collisions, $\sqrt{s}$=7.0 GeV,
with the ALICE detector.


title: A dynamical characterization of universally tight lens spaces

abstract:
  We give necessary and sufficient conditions for a closed connected
co-orientable contact $3$-manifold $(M,\xi)$ to be a standard lens space based
on assumptions on the Reeb flow associated to a defining contact form. Our
methods also provide rational global surfaces of section for nondegenerate Reeb
flows on $(L(p,q),\xi_{\rm std})$ with prescribed binding orbits.


title: Photoproduction and mixing effects of scalar a0 and f0 mesons

abstract:
  The photoproduction processes gp-->a0(980)p and gp-->f0(980)p at energies
close to threshold are considered. These reactions are studied in the \pi\pi p,
\pi\eta p, and K-barK p channels. Production cross sections are estimated in
different models. The role of the a0^0-f0 mixing is examined in the invariant
\pi\pi-,\pi\eta-, and K-barK-mass spectra.


title: A Unified Theory of Quasibound States

abstract:
  We have developed a formalism that includes both quasibound states with real
energies and quantum resonances within the same theoretical framework, and that
admits a clean and unambiguous distinction between these states and the states
of the embedding continuum. States described broadly as 'quasibound' are
defined as having a connectedness (in the mathematical sense) to true bound
states through the growth of some parameter. The approach taken here builds on
our earlier work by clarifying several crucial points and extending the
formalism to encompass a variety of continuous spectra, including those with
degenerate energy levels. The result is a comprehensive framework for the study
of quasibound states. The theory is illustrated by examining several cases
pertinent to applications widely discussed in the literature.


title:
Generalised cusp anomalous dimension in beta-deformed super Yang Mills
  theory

abstract:
  In this work we study the cusp anomalous dimension of the marginally deformed
N=4 sYM theory. We find the expression of the cusp anomalous dimension both at
the weak and strong coupling limits. On the gravity side we partially map the
system of equations to that of undeformed N=4 sYM, by defining in the internal
space an effective angle \Delta \theta_{eff} which depends on the deformation
parameter. The cusp anomalous dimension then can be read from that of the N=4
sYM theory, by using this effective angle instead of the usual angle of the
undeformed 5-sphere. In the weak coupling regime we find no beta dependence up
to two loops. Based on these results we conjecture that for any value of
lambda, the cusp anomalous dimension is given by the N=4 sYM result using the
coupling dependent effective angle. As a consequence of this, we derive a
BPS-like condition between the angle of the AdS space and the \Delta
\theta_{eff} of the deformed sphere which when satisfied, nullifies the cusp
anomalous dimension.


title: On the possibility of measuring the Unruh effect

abstract:
  There is a persistent state of confusion regarding the nature of the Unruh
effect. We will argue that, in contrast to some interpretations thereof, the
effect does not represent any novel physics and that, by its very nature, the
effect is fundamentally unmeasurable in all experiments of the kind that have
been contemplated until now. Also, we discuss what aspects connected with this
effect one might consider as possibilities to be explored empirically and what
their precise meaning may be regarding the issue at hand.


title:
Measuring fermion parity correlations and relaxation rates in 1D
  topological superconducting wires

abstract:
  Zero energy Majorana fermion states (Majoranas) can arise at the ends of a
semiconducting wire in proximity with a superconductor. A first generation of
experiments has detected a zero bias conductance peak in these systems that
strongly suggests these Majoranas do exist; however, a definitive demonstration
of the long-ranged entanglement that is crucial for potential applications in
quantum computing has yet to be carried out. This work discusses two possible
measurement schemes to detect this long-ranged entanglement in a wire system
with two coupled pairs of Majoranas, by varying the coupling between one pair
while measuring the fermion parity of the second pair. First, in a system with
two coupled pairs of Majoranas, we discuss how varying the coupling of one pair
in time, while measuring temporal fermion parity correlations of the second
pair, allows for an experimental probe of long-ranged Majorana entanglement.
Second, we show that the power spectrum of the charge noise (fermion parity
noise) of one pair contains signatures of these correlations, as well as
allowing one to infer the parity relaxation rate.


title: Photoevaporation of Circumstellar Disks Revisited: The Dust-Free Case

abstract:
  Photoevaporation by stellar ionizing radiation is believed to play an
important role in the dispersal of disks around young stars. The mass loss
model for dust-free disks developed by Hollenbach et al. is currently regarded
as a conventional one and has been used in a wide variety of studies. However,
the rate in this model was derived by the crude so-called 1+1D approximation of
ionizing radiation transfer, which assumes that diffuse radiation propagates in
a direction vertical to the disk. In this study, we revisit the
photoevaporation of dust-free disks by solving the 2D axisymmetric radiative
transfer for steady-state disks. Unlike that solved by the conventional model,
we determine that direct stellar radiation is more important than the diffuse
field at the disk surface. The radial density distribution at the ionization
boundary is represented by the single power-law with an index -3/2 in contrast
to the conventional double power-law. For this distribution, the
photoevaporation rate from the entire disk can be written as a function of the
ionizing photon emissivity, Phi_EUV, from the central star and the disk outer
radius, r_d, as follows: Mdot_PE = 5.4 x 10^-5 x (Phi_EUV/10^49 sec^-1)^1/2 x
(r_d/1000 AU)^1/2 Msun/yr. This new rate depends on the outer disk radius
rather than on the gravitational radius as in the conventional model, caused by
the enhanced contribution to the mass loss from the outer disk annuli. In
addition, we discuss its applications to present-day as well as primordial star
formation.


title:
A Radio-Selected Black Hole X-ray Binary Candidate in the Milky Way
  Globular Cluster M62

abstract:
  We report the discovery of a candidate stellar-mass black hole in the Milky
Way globular cluster M62. We detected the black hole candidate, which we term
M62-VLA1, in the core of the cluster using deep radio continuum imaging from
the Karl G. Jansky Very Large Array. M62-VLA1 is a faint source, with a flux
density of 18.7 +/- 1.9 microJy at 6.2 GHz and a flat radio spectrum
(alpha=-0.24 +/- 0.42, for S_nu = nu^alpha). M62 is the second Milky Way
cluster with a candidate stellar-mass black hole; unlike the two candidate
black holes previously found in the cluster M22, M62-VLA1 is associated with a
Chandra X-ray source, supporting its identification as a black hole X-ray
binary. Measurements of its radio and X-ray luminosity, while not simultaneous,
place M62-VLA1 squarely on the well-established radio--X-ray correlation for
stellar-mass black holes. In archival Hubble Space Telescope imaging, M62-VLA1
is coincident with a star near the lower red giant branch. This possible
optical counterpart shows a blue excess, H alpha emission, and optical
variability. The radio, X-ray, and optical properties of M62-VLA1 are very
similar to those for V404 Cyg, one of the best-studied quiescent stellar-mass
black holes. We cannot yet rule out alternative scenarios for the radio source,
such as a flaring neutron star or background galaxy; future observations are
necessary to determine whether M62-VLA1 is indeed an accreting stellar-mass
black hole.


title:
Modification of the MOOG spectral synthesis codes to account for Zeeman
  broadening of spectral lines

abstract:
  In an attempt to widen access to the study of magnetic fields in stellar
astronomy, I present MOOGStokes, a version of the MOOG one-dimensional LTE
radiative transfer code, overhauled to incorporate a Stokes vector treatment of
polarized radiation through a magnetic medium. MOOGStokes is a suite of three
complementary programs, which together can synthesize the disk-averaged
emergent spectrum of a star with a magnetic field. The first element (a
pre-processing script called CounterPoint) calculates for a given magnetic
field strength, wavelength shifts and polarizations for the components of
Zeeman sensitive lines. The second element (a MOOG driver called SynStokes
derived from the existing MOOG driver Synth) uses the list of Zeeman shifted
absorption lines together with the existing machinery of MOOG to synthesize the
emergent spectrum at numerous locations across the stellar disk, accounting for
stellar and magnetic field geometry. The third and final element (a
post-processing script called DiskoBall) calculates the disk-averaged spectrum
by weighting the individual emergent spectra by limb darkening and projected
area, and applying the effects of Doppler broadening. All together, the
MOOGStokes package allows users to synthesize emergent spectra of stars with
magnetic fields in a familiar computational framework. MOOGStokes produces
disk-averaged spectra for all Stokes vectors (I, Q, U, and V), normalized by
the continuum. MOOGStokes agrees well with the predictions of INVERS10 a
polarized radiative transfer code with a long history of use in the study of
stellar magnetic fields. In the non-magnetic limit, MOOGStokes also agrees with
the predictions of the scalar version of MOOG.


title: Kuiper Belt Occultation Predictions

abstract:
  Here we present observations of 7 large Kuiper Belt Objects. From these
observations, we extract a point source catalog with $\sim0.01"$ precision, and
astrometry of our target Kuiper Belt Objects with $0.04-0.08"$ precision within
that catalog. We have developed a new technique to predict the future
occurrence of stellar occultations by Kuiper Belt Objects. The technique makes
use of a maximum likelihood approach which determines the best-fit adjustment
to cataloged orbital elements of an object. Using simulations of a theoretical
object, we discuss the merits and weaknesses of this technique compared to the
commonly adopted ephemeris offset approach. We demonstrate that both methods
suffer from separate weaknesses, and thus, together provide a fair assessment
of the true uncertainty in a particular prediction. We present occultation
predictions made by both methods for the 7 tracked objects, with dates as late
as 2015. Finally, we discuss observations of three separate close passages of
Quaoar to field stars, which reveal the accuracy of the element adjustment
approach, and which also demonstrate the necessity of considering the
uncertainty in stellar position when assessing potential occultations.


title: The Mass Distribution of Subgiant Planet Hosts

abstract:
  High mass stars are hostile to Doppler measurements due to rotation and
activity on the main-sequence, so radial velocity searches for planets around
massive stars have relied on evolved stars. A large number of planets have been
found around evolved stars with M>1.5 Msun. To test the robustness of mass
determinations, Lloyd (2011) compared mass distributions of planet hosting
subgiants with distributions from integrating isochrones and concluded it is
unlikely the subgiant planet hosts are this massive, but rather the mass
inferences are systematically in error. The conclusions of Lloyd (2011) have
been called in to question by Johnson, Morton & Wright (2013), who show
TRILEGAL-based mass distributions disagree with the mass distributions in Lloyd
(2011), which they attribute to Malmquist bias. Johnson, Morton & Wright (2013)
argue that the very small spectroscopic observational uncertainties favor high
masses, and there are a large number of high mass sub giants in RV surveys.
However, in this letter, it is shown that Malmquist bias does not impact the
mass distributions, but the mass distribution is sensitive to Galaxy model. The
relationship needed to reconcile the subgiant planet host masses with any model
of the Galactic stellar population is implausible, and the conclusion of Lloyd
(2011) that spectroscopic mass determinations of subgiants are likely to have
been overestimated is robust.


title:
Local Group timing in Milgromian dynamics. A past Milky Way-Andromeda
  encounter at z>0.8

abstract:
  The Local Group timing has been one of the first historical probes of the
missing mass problem. Whilst modern cosmological probes indicate that pure
baryonic dynamics is not sufficient on the largest scales, nearby galaxies and
small galaxy groups persistently obey Milgrom's MOND law, which implies that
dynamics at small scales is possibly entirely predicted by the baryons. Here,
we investigate the Local Group timing in this context of Milgromian dynamics.
Making use of the latest measured proper motions and radial velocities for
Andromeda and the Magellanic clouds, we integrate backwards their orbits by
making use of the Milgromian two-body equation of motion. We find that, with
the currently measured proper motions and radial velocity of M31, MOND would
imply that the Milky Way and M31 first moved apart via Hubble expansion after
birth, but then necessarily got attracted again by the Milgromian gravitational
attraction, and had a past fly-by encounter before coming to their present
positions. This encounter would most probably have happened 7 to 11 Gyr ago
(0.8<z<3). The absence of a dark matter halo and its associated dynamical
friction is necessary for such a close encounter not to trigger a merger.
Observational arguments which could exclude or favour such a past encounter
would thus be very important in view of falsifying or vindicating Milgromian
dynamics on the scale of the Local Group. Interestingly, the closest approach
of the encounter is small enough (<55 kpc) to have severe consequences on the
disk dynamics, including perhaps thick disk formation, and on the satellite
systems of both galaxies. The ages of the satellite galaxies and of the young
halo globular clusters, all of which form the vast polar structure around the
Milky Way, are consistent with these objects having been born in this
encounter.


title: Topology of Future Infinity in dS/CFT

abstract:
  The dS/CFT proposal of Anninos, Hartman, and Strominger relates quantum
Vasiliev gravity in dS_4 to a large N vector theory in three dimensions. We use
this proposal to compute the Wheeler-de Witt wave function of a universe having
a particular topology at future infinity. This amplitude is found to grow
rapidly with the topological complexity of the spatial slice; this is due to
the plethora of states of the Chern-Simons theory that is needed to impose the
singlet constraint. Various mechanisms are considered which might ameliorate
this growth, but none seems completely satisfactory. We also study the topology
dependence in Einstein gravity by computing the action of complex instantons;
the wave function then depends on a choice of contour through the space of
metrics. The most natural contour prescription leads to a growth with genus
similar to the one found in Vasiliev theory, albeit with a different power of
Newton's constant.


title: Calculating Track Thrust with Track Functions

abstract:
  In e+e- event shapes studies at LEP, two different measurements were
sometimes performed: a "calorimetric" measurement using both charged and
neutral particles, and a "track-based" measurement using just charged
particles. Whereas calorimetric measurements are infrared and collinear safe
and therefore calculable in perturbative QCD, track-based measurements
necessarily depend on non-perturbative hadronization effects. On the other
hand, track-based measurements typically have smaller experimental
uncertainties. In this paper, we present the first calculation of the event
shape track thrust and compare to measurements performed at ALEPH and DELPHI.
This calculation is made possible through the recently developed formalism of
track functions, which are non-perturbative objects describing how energetic
partons fragment into charged hadrons. By incorporating track functions into
soft-collinear effective theory, we calculate the distribution for track thrust
with next-to-leading logarithmic resummation. Due to a partial cancellation
between non-perturbative parameters, the distributions for calorimeter thrust
and track thrust are remarkably similar, a feature also seen in LEP data.


title: Non-Degenerate Squarks from Flavored Gauge Mediation

abstract:
  We study the squark spectra of Flavored Gauge Mediation Models, in which
messenger-matter superpotential couplings generate new, generation-dependent
contributions to the squark masses. The new couplings are controlled by the
same flavor symmetry that explains the fermion masses, leading to excellent
alignment of the quark and squark mass matrices. This allows for large squark
mass splittings consistent with all flavor bounds. In particular,
second-generation squarks are often significantly lighter than the
first-generation squarks. As squark production at the LHC is dominated by the
up- and down-squarks and the efficiencies for squark searches increase with
their masses, the charm and/or strange squark masses can be well below the
current LHC bounds. At the same time, even with a single set of messengers, the
models can generate large stop mixings which result in large loop contributions
to the Higgs mass.


title:
Numerical Simulations of Bubble-Induced Star Formation in Dwarf
  Irregular Galaxies with a Novel Stellar Feedback Scheme

abstract:
  To study the star formation and feedback mechanism, we simulate the evolution
of an isolated dwarf irregular galaxy (dIrr) in a fixed dark matter halo,
similar in size to WLM, using a new stellar feedback scheme. We use the new
version of our original N-body/smoothed particle chemodynamics code, GCD+,
which adopts improved hydrodynamics, metal diffusion between the gas particles
and new modelling of star formation and stellar wind and supernovae (SNe)
feedback. Comparing the simulations with and without stellar feedback effects,
we demonstrate that the collisions of bubbles produced by strong feedback can
induce star formation in a more widely spread area. We also demonstrate that
the metallicity in star forming regions is kept low due to the mixing of the
metal-rich bubbles and the metal-poor inter-stellar medium. Our simulations
also suggest that the bubble-induced star formation leads to many
counter-rotating stars. The bubble-induced star formation could be a dominant
mechanism to maintain star formation in dIrrs, which is different from larger
spiral galaxies where the non-axisymmetric structures, such as spiral arms, are
a main driver of star formation.


title: An approximate NNNLO cross section for Higgs production in gluon fusion

abstract:
  An approximate expression for the inclusive Higgs production cross section in
gluon fusion at NNNLO in QCD with finite top mass is presented. We argue that
an accurate approximation can be constructed combining (and improving) the
large- and small-z behaviours of the partonic cross section, which are both
known to all orders from soft-gluon (Sudakov) and high-energy (BFKL)
resummations, respectively. For a 125 GeV Higgs at LHC at 8 TeV, we find an
increase of about 6-13% with respect to the NNLO inclusive cross section for
the conventional scale \mu_R=m_H/2, suggesting that higher order QCD
corrections might be underestimated by presently available results. We also
find a significant reduction of the scale uncertainty.


title: Current Sheets Formation in Tangled Coronal Magnetic Fields

abstract:
  We investigate the dynamical evolution of magnetic fields in closed regions
of solar and stellar coronae. To understand under which conditions current
sheets form, we examine dissipative and ideal reduced magnetohydrodynamic
models in cartesian geometry, where two magnetic field components are present:
the strong guide field $B_0$, extended along the axial direction, and the
dynamical orthogonal field $\mathbf{b}$. Magnetic field lines thread the system
along the axial direction, that spans the length $L$, and are line-tied at the
top and bottom plates. The magnetic field $b$ initially has only large scales,
with its gradient (current) length-scale of order $\ell_b$. We identify the
magnetic intensity threshold $b/B_0 \sim \ell_b/L$. For values of $b$ below
this threshold, field-line tension inhibits the formation of current sheets,
while above the threshold they form quickly on fast ideal timescales. In the
ideal case, above the magnetic threshold, we show that current sheets thickness
decreases in time until it becomes smaller than the grid resolution, with the
analyticity strip width $\delta$ decreasing at least exponentially, after which
the simulations become under-resolved.


title: Can supermassive black hole seeds form in galaxy mergers?

abstract:
  It has been recently suggested that supermassive black holes at z = 5-6 might
form from super-fast (\dot M > 10^4 Msun/yr) accretion occurring in unstable,
massive nuclear gas disks produced by mergers of Milky-Way size galaxies.
Interestingly, such mechanism is claimed to work also for gas enriched to solar
metallicity. These results are based on an idealized polytropic equation of
state assumption, essentially preventing the gas from cooling. We show that
under more realistic conditions, the disk rapidly (< 1 yr) cools, the accretion
rate drops, and the central core can grow only to \approx 100 Msun. In
addition, most of the disk becomes gravitationally unstable in about 100 yr,
further quenching the accretion. We conclude that this scenario encounters a
number of difficulties that possibly make it untenable.


title:
An empirical formula for the distribution function of a thin exponential
  disc

abstract:
  An empirical formula for a Shu distribution function that reproduces a thin
disc with exponential surface density to good accuracy is presented. The
formula has two free parameters that specify the functional form of the
velocity dispersion. Conventionally, this requires the use of an iterative
algorithm to produce the correct solution, which is computationally taxing for
applications like Markov Chain Monte Carlo (MCMC) model fitting. The formula
has been shown to work for flat, rising and falling rotation curves.
Application of this methodology to one of the Dehnen distribution functions is
also shown. Finally, an extension of this formula to reproduce velocity
dispersion profiles that are an exponential function of radius is also
presented. Our empirical formula should greatly aid the efficient comparison of
disc models with large stellar surveys or N-body simulations.


title:
Dynamical signatures of infall around galaxy clusters: a generalized
  Jeans equation

abstract:
  We study the internal kinematics of galaxy clusters in the region beyond the
sphere of virialization. Galaxies around a virialized cluster are infalling
towards the cluster centre with a non-zero mean radial velocity. We develop a
new formalism for describing the dynamical state of clusters, by generalizing
the standard Jeans formalism with the inclusion of the peculiar infall motions
of galaxies and the Hubble expansion as well as the contributions due to
background cosmology. Using empirical fits to the radial profiles of density,
mean radial velocity and velocity anisotropy of both a stacked cluster-mass
halo and two isolated halos of a cosmological dark matter only simulation, we
verify that our generalized Jeans equation correctly predicts the radial
velocity dispersion out to 4 virial radii. We find that the radial velocity
dispersion inferred from the standard Jeans equation is accurate up to 2 virial
radii, but overestimated by \approx 20% for the stacked halo and by \approx 40%
for the isolated halos, in the range \approx 2-3 virial radii. Our model
depends on the logarithmic growth rate of the virial radius (function of halo
mass or concentration), which we estimate in 7 different ways, and on the
departure from self-similarity of the evolution of the peculiar velocity
profile in virial units.


title: Ricci dark energy in Chern-Simons modified gravity

abstract:
  In this work, we have considered the Ricci dark energy model, where the
energy density of the universe is proportional to the Ricci scalar curvature,
in the dynamic Chern-Simons modified gravity. We show that in this context the
evolution of the scale factor is similar to that displayed by the modified
Chaplygin gas.


title: Enhanced noise at high bias in atomic-scale Au break junctions

abstract:
  Heating in nanoscale systems driven out of equilibrium is of fundamental
importance, has ramifications for technological applications, and is a
challenge to characterize experimentally. Prior experiments using nanoscale
junctions have largely focused on heating of ionic degrees of freedom, while
heating of the electrons has been mostly neglected. We report measurements in
atomic-scale Au break junctions, in which the bias-driven component of the
current noise is used as a probe of the electronic distribution. At low biases
($<$ 150~mV) the noise is consistent with expectations of shot noise at a fixed
electronic temperature. At higher biases, a nonlinear dependence of the noise
power is observed. We consider candidate mechanisms for this increase,
including flicker noise (due to ionic motion), heating of the bulk electrodes,
nonequilibrium electron-phonon effects, and local heating of the electronic
distribution impinging on the ballistic junction. We find that flicker noise
and bulk heating are quantitatively unlikely to explain the observations. We
discuss the implications of these observations for other nanoscale systems, and
experimental tests to distinguish vibrational and electron interaction
mechanisms for the enhanced noise.


title:
Spherically symmetric model stellar atmospheres and limb darkening II:
  limb-darkening laws, gravity-darkening coefficients and angular diameter
  corrections for FGK dwarf stars

abstract:
  Limb darkening is a fundamental ingredient for interpreting observations of
planetary transits, eclipsing binaries, optical/infrared interferometry and
microlensing events. However, this modeling traditionally represents limb
darkening by a simple law having one or two coefficients that have been derived
from plane-parallel model stellar atmospheres, which has been done by many
researchers. More recently, researchers have gone beyond plane-parallel models
and considered other geometries. We previously studied the limb-darkening
coefficients from spherically symmetric and plane-parallel model stellar
atmospheres for cool giant and supergiant stars, and in this investigation we
apply the same techniques to FGK dwarf stars. We present limb-darkening
coefficients, gravity-darkening coefficients and interferometric angular
diameter corrections from Atlas and SAtlas model stellar atmospheres. We find
that sphericity is important even for dwarf model atmospheres, leading to
significant differences in the predicted coefficients.


title: Long-distance distribution of genuine energy-time entanglement

abstract:
  Any practical realization of entanglement-based quantum communication must be
intrinsically secure and able to span long distances avoiding the need of a
straight line between the communicating parties. The violation of Bell's
inequality offers a method for the certification of quantum links without
knowing the inner workings of the devices. Energy-time entanglement quantum
communication satisfies all these requirements. However, currently there is a
fundamental obstacle with the standard configuration adopted: an intrinsic
geometrical loophole that can be exploited to break the security of the
communication, in addition to other loopholes. Here we show the first
experimental Bell violation with energy-time entanglement distributed over 1 km
of optical fibers that is free of this geometrical loophole. This is achieved
by adopting a new experimental design, and by using an actively stabilized
fiber-based long interferometer. Our results represent an important step
towards long-distance secure quantum communication in optical fibers.


title: The galaxy environment of a QSO at z ~ 5.7

abstract:
  High-redshift quasars are believed to reside in massive halos in the early
universe and should therefore be located in fields with overdensities of
galaxies, which are thought to evolve into galaxy clusters seen in the local
universe. However, despite many efforts, the relationship between galaxy
overdensities and z~6 quasars is ambiguous. This can possibly be attributed to
the difficulty of finding galaxies with accurate redshifts in the vicinity of
z~6 quasars. So far, overdensity searches around z~6 quasars have been based on
studies of Lyman break galaxies (LBGs), which probe a redshift range of Delta z
~ 1. This range is large enough to select galaxies that may not be physically
related to the quasar. We use deep narrow- and broadband imaging to study the
environment of the z=5.72 quasar ULAS J0203+0012. The redshift range probed by
our narrow-band selection of Lyman alpha emitters (LAEs) is Delta z ~ 0.1,
which is significantly narrower than the LBG searches. This is the first time
that LAEs were searched for near a z~6 quasar, in an effort to provide clues
about the environments of quasars at the end of the epoch of reionization. We
find no enhancement of LAEs in the surroundings of ULAS J0203+0012 in
comparison with blank fields. We explore different explanations and
interpretations for this non-detection of a galaxy overdensity, including that
(1) the strong ionization from the quasar may prevent galaxy formation in its
immediate vicinity and (2) high-redshift quasars may not reside in the center
of the most massive dark matter halos.


title:
Search for top squarks in R-parity-violating supersymmetry using three
  or more leptons and b-tagged jets

abstract:
  A search for anomalous production of events with three or more isolated
leptons and bottom-quark jets produced in pp collisions at sqrt(s) = 8 TeV is
presented. The analysis is based on a data sample corresponding to an
integrated luminosity of 19.5 inverse femtobarns collected by the CMS
experiment at the LHC in 2012. No excess above the standard model expectations
is observed. The results are interpreted in the context of supersymmetric
models with signatures that have low missing transverse energy arising from
light top-squark pair production with R-parity-violating decays of the lightest
supersymmetric particle. In two models with different R-parity-violating
couplings, top-squarks are excluded below masses of 1020 GeV and 820 GeV when
the lightest supersymmetric particle has a mass of 200 GeV.


title:
Forecasting constraints on the cosmic duality relation with galaxy
  clusters

abstract:
  One of the fundamental hypotheses in observational cosmology is the validity
of the so-called cosmic distance-duality relation (CDDR). In this paper, we
perform Monte Carlo simulations based on the method developed in Holanda,
Goncalves & Alcaniz (2012) [JCAP 1206 (2012) 022] to answer the following
question: what is the number of galaxy clusters observations N_{crit} needed to
check the validity of this relation at a given confidence level? At 2\sigma, we
find that N_{crit} should be increased at least by a factor of 5 relative to
the current sample size if we assume the current observational uncertainty
\sigma_{obs}. Reducing this latter quantity by a factor of 2, we show that the
present number of data would be already enough to check the validity of the
CDDR at 2\sigma.


title:
Effective action and phase transitions of scalar field on the fuzzy
  sphere

abstract:
  Scalar field theory on the fuzzy two-sphere, represented as a hermitian
matrix model that includes kinetic, mass and quartic interaction terms, is
studied. The effective action in the symmetric large-N regime is analyzed using
a self-consistent bootstrap method which fixes its form up to sixth order in
the eigenvalues and gives a closed expression to all orders in the quadratic
invariant of the matrix, valid close to semicircular distributions. Using this
action the eigenvalue distribution is calculated for the interacting theory in
the appropriate scaling limit and the phase transition from the disordered to
the symmetric ordered phase is identified, including nonperturbative effects.

categories: hep-th cond-mat.stat-mech math-ph math.MP


title: Large-scale 3D galaxy correlation function and non-Gaussianity

abstract:
  We investigate the properties of the 2-point galaxy correlation function at
very large scales, including all geometric and local relativistic effects --
wide-angle effects, redshift space distortions, Doppler terms and Sachs-Wolfe
type terms in the gravitational potentials. The general three-dimensional
correlation function has a nonzero dipole and octupole, in addition to the even
multipoles of the flat-sky limit. We study how corrections due to primordial
non-Gaussianity and General Relativity affect the multipolar expansion, and we
show that they are of similar magnitude (when f_NL is small), so that a
relativistic approach is needed. Furthermore, we look at how large-scale
corrections depend on the model for the growth rate in the context of modified
gravity, and we discuss how a modified growth can affect the non-Gaussian
signal in the multipoles.


title: Photometric and spectroscopic variability of the FUor star V582 Aurigae

abstract:
  We carried out BVRI CCD photometric observations in the field of V582 Aur
from 2009 August to 2013 February. We acquired high-, medium-, and
low-resolution spectroscopy of V582 Aur during this period. To study the
pre-outburst variability of the target and construct its historical light
curve, we searched for archival observations in photographic plate collections.
Both CCD and photographic observations were analyzed using a sequence of 14
stars in the field of V582 Aur calibrated in BVRI. The pre-outburst
photographic observations of V582 Aur show low-amplitude light variations
typical of T Tauri stars. Archival photographic observations indicate that the
increase in brightness began in late 1984 or early 1985 and the star reached
the maximum level of brightness at 1986 January. The spectral type of V582 Aur
can be defined as G0I with strong P Cyg profiles of H alpha and Na I D lines,
which are typical of FU Orionis objects. Our BVRI photometric observations show
large amplitude variations V~2.8 mag. during the 3.5 year period of
observations. Most of the time, however, the star remains in a state close to
the maximum brightness. The deepest drop in brightness was observed in the
spring of 2012, when the brightness of the star fell to a level close to the
pre-outburst. The multicolor photometric data show a color reversal during the
minimum in brightness, which is typical of UX Ori variables. The corresponding
spectral observations show strong variability in the profiles and intensities
of the spectral lines (especially H alpha), which indicate significant changes
in the accretion rate. On the basis of photometric monitoring performed over
the past three years, the spectral properties of the maximal light, and the
shape of the long-term light curve, we confirm the affiliation of V582 Aur to
the group of FU Orionis objects.


title: Finite momentum at string endpoints

abstract:
  We argue that classical strings, both bosonic and supersymmetric, can have
finite energy and momentum at their endpoints. We show that in a general curved
background, string endpoints must propagate along null geodesics as long as
their energy remains finite. Finite endpoint momentum allows strings with a
fixed energy to travel a greater distance in an AdS5-Schwarzschild background
than has been possible for classical solutions considered previously. We review
the relevance to heavy ion phenomenology of the dependence of this distance on
energy, and we propose a scheme for determining the instantaneous rate of
energy loss.


title: Measurements of collective machine intelligence

abstract:
  Independent from the still ongoing research in measuring individual
intelligence, we anticipate and provide a framework for measuring collective
intelligence. Collective intelligence refers to the idea that several
individuals can collaborate in order to achieve high levels of intelligence. We
present thus some ideas on how the intelligence of a group can be measured and
simulate such tests. We will however focus here on groups of artificial
intelligence agents (i.e., machines). We will explore how a group of agents is
able to choose the appropriate problem and to specialize for a variety of
tasks. This is a feature which is an important contributor to the increase of
intelligence in a group (apart from the addition of more agents and the
improvement due to common decision making). Our results reveal some interesting
results about how (collective) intelligence can be modeled, about how
collective intelligence tests can be designed and about the underlying dynamics
of collective intelligence. As it will be useful for our simulations, we
provide also some improvements of the threshold allocation model originally
used in the area of swarm intelligence but further generalized here.