title: Super Luminous Ic Supernovae: catching a magnetar by the tail

abstract:
  We report extensive observational data for five of the lowest redshift
Super-Luminous Type Ic Supernovae (SL-SNe Ic) discovered to date, namely
PTF10hgi, SN2011ke, PTF11rks, SN2011kf and SN2012il. Photometric imaging of the
transients at +50 to +230 days after peak combined with host galaxy subtraction
reveals a luminous tail phase for four of these SL-SNe. A high resolution,
optical and near infrared spectrum from xshooter provides detection of a broad
He I $\lambda$10830 emission line in the spectrum (+50d) of SN2012il, revealing
that at least some SL-SNe Ic are not completely helium free. At first sight,
the tail luminosity decline rates that we measure are consistent with the
radioactive decay of \co, and would require 1-4M of \ni to produce the
luminosity. These \ni masses cannot be made consistent with the short diffusion
times at peak, and indeed are insufficient to power the peak luminosity. We
instead favour energy deposition by newborn magnetars as the power source for
these objects. A semi-analytical diffusion model with energy input from the
spin-down of a magnetar reproduces the extensive lightcurve data well. The
model predictions of ejecta velocities and temperatures which are required are
in reasonable agreement with those determined from our observations. We derive
magnetar energies of $0.4\lesssim E$($10^{51}$erg) $\lesssim6.9$ and ejecta
masses of $2.3\lesssim M_{ej}$(\M) $\lesssim 8.6$. The sample of five SL-SNe Ic
presented here, combined with SN 2010gx - the best sampled SL-SNe Ic so far -
point toward an explosion driven by a magnetar as a viable explanation for all
SL-SNe Ic.


title: p-adic Gamma function and traces of Frobenius of elliptic curves

abstract:
  In \cite{mccarthy2}, McCarthy defined a function $_{n}G_{n}[\cdots]$ using
Teichm\"{u}ller character of finite fields and quotients of $p$-adic gamma
function, and expressed the trace of Frobenius of elliptic curves in terms of
special values of $_{2}G_{2}[\cdots]$. We establish two different expressions
for the traces of Frobenius of elliptic curves in terms of the function
$_{2}G_{2}[\cdots]$. As a result, we obtain two relations between special
values of the function $_{2}G_{2}[\cdots]$ with different parameters.


title: Homogeneous projective varieties with semi-continuous rank function

abstract:
  Let $\mathbb X\subset\mathbb P(V)$ be a projective variety, which is not
contained in a hyperplane. Then every vector $v$ in $V$ can be written as a sum
of vectors from the affine cone $X$ over $\mathbb X$. The minimal number of
summands in such a sum is called the rank of $v$. The set of vectors of rank
$r$ is denoted by $X_r$ and its projective image by $\mathbb X_r$. The r-th
secant variety of $X$ is defined $\sigma_r(\mathbb X):=\bar{\sqcup_{s\le
r}\mathbb X_s}$; it is called tame if $\sigma_r(\mathbb X)=\sqcup_{s\le r}
\mathbb X_s$ and wild if the closure contains elements of higher rank. In this
paper, we classify all equivariantly embedded homogeneous projective varieties
$\mathbb X\subset\mathbb P(V)$ with tame secant varieties. Classical examples
are: the variety of rank one matrices (Segre variety with two factors) and the
variety of rank one quadratic forms (quadratic Veronese variety). In the
general setting, $\mathbb X$ is the orbit in $\mathbb P(V)$ of a highest weight
line in an irreducible representation $V$ of a reductive algebraic group $G$.
Thus, our result is a list of all irreducible representations of reductive
groups, where the resulting $\mathbb X$ has tame secant varieties.


title: Exploring exchange mechanisms with a cold atom gas

abstract:
  Fermionic atoms trapped in a double well potential are an ideal setting to
study fundamental exchange mechanisms. We use exact diagonalization and
complementary analytic calculations to demonstrate that two trapped fermions
deliver a minimal model of the direct exchange mechanism. This is an ideal
quantum simulator of the Heisenberg antiferromagnet, exposes the competition
between covalent and ionic bonding, and can create, manipulate, and detect
quantum entanglement. Three trapped atoms form a faithful simulator of the
double exchange mechanism that is the fundamental building block behind many
Heisenberg ferromagnets.


title: Measurements of Top Quark Properties at the LHC

abstract:
  Recent measurements of top quark properties at the LHC from ATLAS and CMS
experiments are presented. The presented results include top quark mass,
dependence of top mass measurements on event kinematics, top anti-top mass
difference, bottom quark content in top quark decays, W boson polarization and
anomalous couplings, search for CP violation in single top events, vector boson
production associated with top-antitop pairs and top polarization.


title:
Buoyancy storms in a zonal stream on the polar beta-plane: experiments
  with altimetry

abstract:
  Results from a new series of experiments on flows generated by localized
heating in the presence of a background zonal current on the polar beta-plane
are presented. The flow induced by a heater without the background zonal flow
is in the form of a beta-plume. Zonal jets of alternating directions are formed
within the plume. The westward transport velocity in the plume is proportional
to the upwelling velocity above the heater in agreement with linear theory.
When the background flow in the form of the eastward zonal current is present,
the beta-plume can be overwhelmed by the eastward current. The main control
parameters of the experiment are the strength of the heater and strength of the
sink which is used to create the background flow. The regime diagram shows the
area where a beta-plume can exist in the parameter space. The critical value of
the velocity of the zonal flow below which the beta-plume can exist is obtained
by considering barotropic Rossby waves emitted by the baroclinic eddies in the
heated area.


title: Hyperfine structure of laser-cooling transitions in fermionic erbium-167

abstract:
  We have measured and analyzed the hyperfine structure of two lines, one at
583nm and one at 401nm, of the only stable fermionic isotope of atomic erbium
as well as determined its isotope shift relative to the four most-abundant
bosonic isotopes. Our work focuses on the J->J+1 laser cooling transitions from
the [Xe] 4f12 6s2 (3H6) ground state to two levels of the excited [Xe] 4f12
6s6p configuration, which are of major interest for experiments on quantum
degenerate dipolar Fermi gases. From a fit to the observed spectra of the
strong optical transition at 401nm we find that the magnetic dipole and
electric quadrupole hyperfine constants for the excited state are
Ae/h=-100.1(3)MHz and Be/h=-3079(30)MHz, respectively. The hyperfine spectrum
of the narrow transition at 583nm, was previously observed and accurate Ae and
Be coefficients are available. A simulated spectrum based on these coefficients
agrees well with our measurements. We have also determined the hyperfine
constants using relativistic configuration-interaction ab initio calculations.
The agreement between the ab initio and fitted data for the ground state is
better than 0.1%, while for the two excited states the agreement is 1% and 11%
for the Ae and Be constants, respectively.


title: Expansive measures for flows

abstract:
  We extend the concept of expansive measure \cite{am} defined for
homeomorphism to flows. We obtain some properties for such measures including
abscense of singularities in the support, aperiodicity, expansivity with
respect to time-$T$ maps, invariance under flow-equivalence, negligibleness of
orbits, characterization of expansive measures for expansive flows and
naturallity under suspensions. As an application we obtain a new proof of the
well known fact that there are no continuous expansive flows on surfaces (e.g.
\cite{hs}).


title: Refined knot invariants and Hilbert schemes

abstract:
  We consider the construction of refined Chern-Simons torus knot invariants by
M. Aganagic and S. Shakirov from the DAHA viewpoint of I. Cherednik. We give a
proof of Cherednik's conjecture on the stabilization of superpolynomials, and
then use the results of O. Schiffmann and E. Vasserot to relate knot invariants
to the Hilbert scheme of points on the plane. Then we use the methods of the
second author to compute these invariants explicitly in the uncolored case. We
also propose a conjecture relating these constructions to the rational
Cherednik algebra, as in the work of the first author, A. Oblomkov, J.
Rasmussen and V. Shende. Among the combinatorial consequences of this work is a
statement of the m/n shuffle conjecture.


title: Mixed Moduli of Smoothness in $L_p$, $1<p<\infty$

abstract:
  In this paper we survey recent developments over the last 25 years on the
mixed fractional moduli of smoothness of periodic functions from $L_p$,
$1<p<\infty$. In particular, the paper includes monotonicity properties,
equivalence and realization results, sharp Jackson, Marchaud, and Ul'yanov
inequalities, interrelations between the moduli of smoothness, the Fourier
coefficients, and "angular" approximation. The sharpness of the results
presented is discussed.


title: Kinetic Solvers with Adaptive Mesh in Phase Space

abstract:
  An Adaptive Mesh in Phase Space (AMPS) methodology has been developed for
solving multi-dimensional kinetic equations by the discrete velocity method. A
Cartesian mesh for both configuration (r) and velocity (v) spaces is produced
using a tree of trees data structure. The mesh in r-space is automatically
generated around embedded boundaries and dynamically adapted to local solution
properties. The mesh in v-space is created on-the-fly for each cell in r-space.
Mappings between neighboring v-space trees implemented for the advection
operator in configuration space. We have developed new algorithms for solving
the full Boltzmann and linear Boltzmann equations with AMPS. Several recent
innovations were used to calculate the discrete Boltzmann collision integral
with dynamically adaptive mesh in velocity space: importance sampling,
multi-point projection method, and the variance reduction method. We have
developed an efficient algorithm for calculating the linear Boltzmann collision
integral for elastic and inelastic collisions in a Lorentz gas. New AMPS
technique has been demonstrated for simulations of hypersonic rarefied gas
flows, ion and electron kinetics in weakly ionized plasma, radiation and light
particle transport through thin films, and electron streaming in
semiconductors. We have shown that AMPS allows minimizing the number of cells
in phase space to reduce computational cost and memory usage for solving
challenging kinetic problems.


title: Zhu-Nakamura theory and the superparabolic level-glancing models

abstract:
  We study the applicability of the Zhu-Nakamura theory to a class of
time-dependent quantum mechanical level-crossing models called superparabolic
level-glancing models. The phenomenon of a level glancing, being on the
borderline between a proper crossing of energy levels and an avoided crossing,
is also an important special case between the two different approximative
expressions in the Zhu-Nakamura theory. It is seen that the application of the
theory to these models is not straightforward. We discuss some possible causes
of these difficulties and also compare the approximative formulas of
Zhu-Nakamura theory to those obtained by the generalization of the DDP theory.


title: A single-spin precessing gravitational wave in closed form

abstract:
  In coming years, gravitational wave detectors should find black hole-neutron
star binaries, potentially coincident with astronomical phenomena like short
GRBs. These binaries are expected to precess. Gravitational wave science
requires a tractable model for precessing binaries, to disentangle precession
physics from other phenomena like modified strong field gravity, tidal
deformability, or Hubble flow; and to measure compact object masses, spins, and
alignments. Moreover, current searches for gravitational waves from compact
binaries use templates where the binary does not precess and are ill-suited for
detection of generic precessing sources. In this paper we provide a closed-form
representation of the single-spin precessing waveform in the frequency domain
by reorganizing the signal as a sum over harmonics, each of which resembles a
nonprecessing waveform. This form enables simple analytic calculations (e.g., a
Fisher matrix) with easily-interpreted results. We have verified that for
generic BH-NS binaries, our model agress with the time-domain waveform to 2\%.
Straightforward extensions of the derivations outlined here [and provided in
full online] allow higher accuracy and error estimates.


title: The Hardy--Littlewood conjecture and rational points

abstract:
  Schinzel's Hypothesis (H) was used by Colliot-Th\'el\`ene and Sansuc, and
later by Serre, Swinnerton-Dyer and others, to prove that the Brauer-Manin
obstruction controls the Hasse principle and weak approximation on pencils of
conics and similar varieties. We show that when the ground field is Q and the
degenerate geometric fibres of the pencil are all defined over Q, one can use
these methods to obtain unconditional results by replacing Hypothesis (H) with
the finite complexity case of the generalised Hardy-Littlewood conjecture
recently established by Green, Tao and Ziegler.


title: Geometric quantum discord with Bures distance

abstract:
  We define a new measure of quantum correlations in bipartite quantum systems
given by the Bures distance of the system state to the set of classical states
with respect to one subsystem, that is, to the states with zero quantum
discord. Our measure is a geometrical version of the quantum discord. As the
latter it quantifies the degree of non-classicality in the system. For pure
states it is identical to the geometric measure of entanglement. We show that
for mixed states it coincides with the optimal success probability of an
ambiguous quantum state discrimination task. Moreover, the closest zero-discord
states to a given state are obtained in terms of the corresponding optimal
measurements.


title:
The Evolution of Dusty Star formation in Galaxy Clusters to z = 1:
  Spitzer IR Observations of the First Red-Sequence Cluster Survey

abstract:
  We present an IR study of high-redshift galaxy clusters with the MIPS camera
on the Spitzer Space Telescope. Employing a sample of 42 clusters from the
RCS-1 over the redshift range 0.3 < z < 1.0 and spanning an approximate range
in mass of 10^{14-15} Msun, we show the number of IR-luminous galaxies in
clusters above a fixed IR luminosity of 2x10^{11} Msun per unit cluster mass
evolves as (1+z)^{5.1+/-1.9}. These results assume a single star forming galaxy
template; the presence of AGN, and an evolution in their relative contribution
to the mid-IR galaxy emission, will alter the overall number counts per cluster
and their rate of evolution. We infer the total SFR per unit cluster mass and
find T_SFR/M_c ~ (1+z)^{5.4+/-1.9}. This evolution can be attributed entirely
to the change in the in-falling field galaxy population. The T_SFR/M_c (binned
over all redshift) decreases with increasing cluster mass with a slope
(T_SFR/M_c ~ M_c^{-1.5+/-0.4}) consistent with the dependence of the
stellar-to-total mass per unit cluster mass seen locally. The inferred star
formation seen here could produce ~5-10% of the total stellar mass in massive
clusters at z = 0. Finally, we show a clear decrease in the number of IR-bright
galaxies per unit optical galaxy in the cluster cores, confirming star
formation continues to avoid the highest density regions of the universe at z ~
0.75 (the average redshift of the high-redshift clusters). While several
previous studies appear to show enhanced star formation in high-redshift
clusters relative to the field we note that these papers have not accounted for
the overall increase in galaxy or dark matter density at the location of
clusters. Once this is done, clusters at z ~ 0.75 have the same or less star
formation per unit mass or galaxy as the field.


title: Pressure induced topological quantum phase transition in Sb_2Se_3

abstract:
  Based on the first-principles band structure calculations, we investigate the
effects of hydrostatic pressure on the conventional insulator (CI) Sb_2Se_3 and
predict that it undergoes a topological quantum phase transition from a CI to a
nontrivial topological insulator at a critical pressure value. The
pressure-induced topological quantum phase transition is confirmed by
calculating the evolution of the bulk energy gap as a function of pressure, the
inversion of energy band structure, and the Z_2 topological invariant, as well
as the existence of the Dirac-like topological surface states. Our predictions
can be tested by both spectroscopy and transport experiments.


title:
Evidence for quasi-chemically homogeneous evolution of massive stars up
  to solar metallicity

abstract:
  Long soft gamma ray bursts (LGRBs) are usually associated with the death of
the most massive stars. A large amount of core angular momentum in the phases
preceding the explosion is required to form LGRBs. A very high initial
rotational velocity can provide this angular momentum. Such a velocity strongly
influences the way the star evolves: it is chemically homogeneously mixed and
evolves directly towards the blue part of the HR diagram from the main
sequence. We have shown that chemically homogeneous evolution (CHE) takes place
in the SMC, at low metallicity. We want to see if there is a metallicity
threshold above which such an evolution does not exist. We perform a
spectroscopic analysis of H-rich early-type WN stars in the LMC and the Galaxy.
We use the code CMFGEN to determine the fundamental properties and the surface
composition of the target stars. We then place the stars in the HR diagram and
determine their evolution. We show that both the LMC and Galactic WNh stars we
selected cannot be explained by standard stellar evolution. They are located on
the left of the main sequence but show surface abundances typical of CN
equilibrium. In addition, they still contain a large amount of hydrogen. They
are thus core-H burning objects. Their properties are consistent with CHE. We
determine the metallicity of the Galactic stars from their position and
Galactic metallicity gradients, and conclude that they have 0.6<Z<1.0. A
moderate coupling between the core and the envelope is required to explain that
stellar winds do not extract to much angular momentum to prevent a blueward
evolution. In view of the findings that some long gamma ray bursts appear in
solar environments, CHE may be a viable way to form them over a wide range of
metallicities.


title: Does the Feigel effect break the first law?

abstract:
  A recent theory posits that the quantum vacuum can transfer momentum to
magnetoelectric media (the Feigel effect). Several related theories of vacuum
momentum transfer to media have since been proposed. Neither these, nor the
original theory have been observed experimentally, the existence a Feigel
effect remaining highly contentious. Some investigations predict a measurable
effect; others conclude vacuum momentum transfer to magnetoelectric media is
not physically possible. Most analyses, including the original Fiegel theory,
do not model experimentally realistic geometries and boundary conditions. I
recently provided an alternative derivation of Feigel theory applied to
realistic geometries, proposing experimental tests. I show here that in such
geometries the existence of a steady Feigel effect (time-independent
magnetoelectric susceptibilities) is equivalent to a violation of the first law
of thermodynamics. A steady Feigel effect should not exist, as confirmed by a
semi-classical quantum electrodynamic analysis. However, unsteady Feigel
effects compatible with QED and thermodynamics are possible, and two such new
effects are proposed.


title:
Lenticular galaxy IC 719: current building of the counterrotating
  large-scale stellar disk

abstract:
  We have obtained and analyzed long-slit spectral data for the lenticular
galaxy IC 719. In this gas-rich S0 galaxy, its large-scale gaseous disk
counterrotates the global stellar disk. Moreover in the IC 719 disk we have
detected a secondary stellar component corotating the ionized gas. By using
emission-line intensity ratios, we have proved the gas excitation by young
stars and so are claiming current star formation, most intense in a ring-like
zone at the radius of 10" (1.4 kpc). The oxygen abundance of the gas in the
starforming ring is about half of the solar abundance. Since the stellar disk
remains dynamically cool, we conclude that smooth prolonged accretion of the
external gas from a neighboring galaxy provides urrent building of the thin
large-scale stellar disk.


title: Detecting quantum non-Gaussianity via the Wigner function

abstract:
  We introduce a family of criteria to detect quantum non-Gaussian states of a
harmonic oscillator, that is, quantum states that can not be expressed as a
convex mixture of Gaussian states. In particular we prove that, for convex
mixtures of Gaussian states, the value of the Wigner function at the origin of
phase space is bounded from below by a non-zero positive quantity, which is a
function only of the average number of excitations (photons) of the state. As a
consequence, if this bound is violated then the quantum state must be quantum
non-Gaussian. We show that this criterion can be further generalized by
considering additional Gaussian operations on the state under examination. We
then apply these criteria to various non-Gaussian states evolving in a noisy
Gaussian channel, proving that the bounds are violated for high values of
losses, and thus also for states characterized by a positive Wigner function.


title: Exoplanet Predictions Based on the Generalised Titius-Bode Relation

abstract:
  We evaluate the extent to which newly detected exoplanetary systems
containing at least four planets adhere to a generalized Titius-Bode (TB)
relation. We find that the majority of exoplanet systems in our sample adhere
to the TB relation to a greater extent than the Solar System does, particularly
those detected by the Kepler mission. We use a generalized TB relation to make
a list of predictions for the existence of 141 additional exoplanets in 68
multiple-exoplanet systems: 73 candidates from interpolation, 68 candidates
from extrapolation. We predict the existence of a low-radius (R < 2.5 Earth
Radii) exoplanet within the habitable zone of KOI-812 and that the average
number of planets in the habitable zone of a star is 1-2. The usefulness of the
TB relation and its validation as a tool for predicting planets will be
partially tested by upcoming Kepler data releases.


title: From ALE to ALF gravitational instantons. II

abstract:
  This paper is the sequel of our previous article "From ALE to ALF
gravitational instantons", where we constructed ALF hyperkahler metrics on
minimal resolutions of dihedral Kleinian singularities. In the present article
we generalize the construction to smooth deformations of these Kleinian
singularities, with help of the computation of the asymptotics of the ALE
gravitational instantons.


title: Givental Action and Trivialisation of Circle Action

abstract:
  In this paper, we show that the Givental group action on genus zero
cohomological field theories, also known as formal Frobenius manifolds or
hypercommutative algebras, naturally arises in the deformation theory of
Batalin--Vilkovisky algebras. We prove that the Givental action is equal to an
action of the trivialisations of the trivial circle action. This result relies
on the equality of two Lie algebra actions coming from two apparently remote
domains: geometry and homotopical algebra.


title:
Four-loop results for the anomalous dimension for a general N=2
  supersymmetric Chern-Simons theory in three dimensions

abstract:
  We present results for the planar contribution to the four-loop anomalous
dimension for a general N=2 supersymmetric Chern-Simons theory in three
dimensions. These results should facilitate higher-order superconformality
checks for theories relevant for the AdS/CFT correspondence.


title: Probabilistic Classification using Fuzzy Support Vector Machines

abstract:
  In medical applications such as recognizing the type of a tumor as Malignant
or Benign, a wrong diagnosis can be devastating. Methods like Fuzzy Support
Vector Machines (FSVM) try to reduce the effect of misplaced training points by
assigning a lower weight to the outliers. However, there are still uncertain
points which are similar to both classes and assigning a class by the given
information will cause errors. In this paper, we propose a two-phase
classification method which probabilistically assigns the uncertain points to
each of the classes. The proposed method is applied to the Breast Cancer
Wisconsin (Diagnostic) Dataset which consists of 569 instances in 2 classes of
Malignant and Benign. This method assigns certain instances to their
appropriate classes with probability of one, and the uncertain instances to
each of the classes with associated probabilities. Therefore, based on the
degree of uncertainty, doctors can suggest further examinations before making
the final diagnosis.


title:
Nondestructive light-shift measurements of single atoms in optical
  dipole traps

abstract:
  We measure the AC-Stark shifts of the 5S{1/2}, F=2 to 5P{3/2}, F'=3
transitions of individual optically trapped 87Rb atoms using a non-destructive
detection technique that allows us to measure the fluorescent signal of
one-and-the-same atom for over 60 seconds. These measurements allow efficient
and rapid characterization of single atom traps that is required for many
coherent quantum information protocols. Although this method is demonstrated
using a single atom trap, the concept is readily extended to resolvable atomic
arrays.


title: Spline regression for zero-inflated models

abstract:
  We propose a regression model for count data when the classical generalized
linear model approach is too rigid due to a high outcome of zero counts and a
nonlinear influence of continuous covariates. Zero-Inflation is applied to take
into account the presence of excess zeros with separate link functions for the
zero and the nonzero component. Nonlinearity in covariates is captured by
spline functions based on B-splines. Our algorithm relies on maximum-likelihood
estimation and allows for adaptive box-constrained knots, thus improving the
goodness of the spline fit and allowing for detection of sensitivity
changepoints. A simulation study substantiates the numerical stability of the
algorithm to infer such models. The AIC criterion is shown to serve well for
model selection, in particular if nonlinearities are weak such that BIC tends
to overly simplistic models. We fit the introduced models to real data of
children's dental sanity, linking caries counts with the so-called
Body-Mass-Index (BMI) and other socioeconomic factors. This reveals a puzzling
nonmonotonic influence of BMI on caries counts which is yet to be explained by
clinical experts.


title:
Fibred coarse embeddings, a-T-menability and the coarse analogue of the
  Novikov conjecture

abstract:
  The connection between the coarse geometry of metric spaces and analytic
properties of topological groupoids is well known. One of the main results of
Skandalis, Tu and Yu is that a space admits a coarse embedding into Hilbert
space if and only if a certain associated topological groupoid is a-T-menable.
This groupoid characterisation then reduces the proof that the coarse
Baum-Connes conjecture holds for a coarsely embeddable space to known results
for a-T-menable groupoids. The property of admitting a fibred coarse embedding
into Hilbert space was introduced by Chen, Wang and Yu to provide a property
that is sufficient for the maximal analogue to the coarse Baum-Connes
conjecture and in this paper we connect this property to the traditional coarse
Baum-Connes conjecture using a restriction of the coarse groupoid and
homological algebra. Additionally we use this results to give a
characterisation of the a-T-menability for residually finite discrete groups.


title: Revisit the carpet cloak from optical conformal mapping

abstract:
  The original carpet cloak [Phys. Rev. Lett. 101, 203901 (2008)] was designed
by a numerical method, the quasi-conformal mapping. Therefore its refractive
index profile was obtained numerically. In this letter, we propose a new carpet
cloak based on the optical conformal mapping, with an analytical form of a
refractive index profile, thereby facilitating future experimental designs.


title:
Return on net sales from three companies in the manufacturing of
  fabricated metal products (except machinery and equipment)

abstract:
  Keywords: corporate finance, Wroc{\l}aw University of Economics, net profit
margin lub net sales profitability


title:
YHap: software for probabilistic assignment of Y haplogroups from
  population re-sequencing data

abstract:
  Y haplogroup analyses are an important component of genealogical
reconstruction, population genetic analyses, medical genetics and forensics.
These fields are increasingly moving towards use of low-coverage, high
throughput sequencing. However, there is as yet no software available for using
sequence data to assign Y haplogroup groups probabilistically, such that the
posterior probability of assignment fully reflects the information present in
the data, and borrows information across all samples sequenced from a
population. YHap addresses this problem.


title: Counting imaginary quadratic points via universal torsors, II

abstract:
  We prove Manin's conjecture for four singular quartic del Pezzo surfaces over
imaginary quadratic number fields, using the universal torsor method.


title: First Principles Study of Bismuth Films on the Nickel(111) Surface

abstract:
  A recent experiment(Bollmann11) suggested that bismuth forms hexagonal close
packed (HCP) films on the Ni(111) surface, of heights 3, 5 and 7 layers. A
quantum size effect based on free electrons was proposed in explanation. To
test this idea, we calculate the total energies of Bi on the Ni(111) surface
using density functional theory. We find that HCP film stabilities disagree
with the observed odd layer preferences, and the structures are mechanically
destabilized by adding capping atoms which pucker the HCP layers. Furthermore,
we find that rhombohedral films based on the bulk Bi structure are
energetically more favorable than the proposed HCP films. These structures also
favor odd numbers of layers, but owing to covalent chemical bonding rather than
confinement of free electrons. Specifically, a strongly bound adsorbed surface
monolayer forms, followed by bulk-like rhombohedral bilayers.


title:
Strong coupling superconductivity and prominent superconducting
  fluctuations in the new superconductor Bi4O4S3

abstract:
  Electric transport and scanning tunneling spectrum (STS) have been
investigated on polycrystalline samples of the new superconductor Bi4O4S3. A
weak insulating behavior in the resistive curve has been induced in the normal
state when the superconductivity is suppressed by applying a magnetic field.
Interestingly, a kink appears on the temperature dependence of resistivity near
4 K at all high magnetic fields above 1 T when the bulk superconductivity is
completely suppressed. This kink associated with the upper critical field as
well as the wide range of excess conductance at low field and high temperature
are explained as the possible evidence of strong superconducting fluctuation.
From the tunneling spectra, a superconducting gap of about 3 meV is frequently
observed yielding a ratio of 2\Delta/(kB*Tc) ~ 16.6. This value is much larger
than the one predicted by the BCS theory in the weak coupling regime
(2\Delta/(kB*Tc) ~ 3.53), which suggests the strong coupling superconductivity
in the present system. Furthermore, the gapped feature persists on the spectra
until 14 K in the STS measurement, which suggests a prominent fluctuation
region of superconductivity. Such superconducting fluctuation can survive at
very high magnetic fields, which are far beyond the critical fields for bulk
superconductivity as inferred both from electric transport and tunneling
measurements.


title:
Convexity of level sets for elliptic problems in convex domains or
  convex rings: two counterexamples

abstract:
  This paper deals with some geometrical properties of solutions of some
semilinear elliptic equations in bounded convex domains or convex rings.
Constant boundary conditions are imposed on the single component of the
boundary when the domain is convex, or on each of the two components of the
boundary when the domain is a convex ring. A function is called quasiconcave if
its superlevel sets, defined in a suitable way when the domain is a convex
ring, are all convex. In this paper, we prove that the superlevel sets of the
solutions do not always inherit the convexity or ring-convexity of the domain.
Namely, we give two counterexamples to this quasiconcavity property: the first
one for some two-dimensional convex domains and the second one for some convex
rings in any dimension.


title: Chiral Symmetry Restoration and Scalar-Pseudoscalar partners in QCD

abstract:
  We describe Scalar-Pseudoscalar partner degeneration at the QCD chiral
transition in terms of the dominant low-energy physical states for the light
quark sector. First, we obtain within model-independent one-loop Chiral
Perturbation Theory (ChPT) that the QCD pseudoscalar susceptibility is
proportional to the quark condensate at low $T$. Next, we show that this
chiral-restoring behaviour for $\chi_P$ is compatible with recent lattice
results for screening masses and gives rise to degeneration between the scalar
and pseudoscalar susceptibilities ($\chi_S$, $\chi_P$) around the transition
point, consistently with an O(4)-like current restoration pattern. This
scenario is clearly confirmed by lattice data when we compare $\chi_S(T)$ with
the quark condensate, expected to scale as $\chi_P(T)$. Finally, we show that
saturating $\chi_S$ with the $\sigma/f_0(500)$ broad resonance observed in pion
scattering and including its finite temperature dependence, allows to describe
the peak structure of $\chi_S(T)$ in lattice data and the associated critical
temperature. This is carried out within a unitarized ChPT scheme which
generates the resonant state dynamically and is also consistent with partner
degeneration.


title:
Performance of Vehicle-to-Vehicle Communication using IEEE 802.11p in
  Vehicular Ad-hoc Network Environment

abstract:
  Traffic safety applications using vehicle-to-vehicle (V2V) communication is
an emerging and promising area within the ITS environment. Many of these
applications require real-time communication with high reliability. To meet a
real-time deadline, timely and predictable access to the channel is paramount.
The medium access method used in 802.11p, CSMA with collision avoidance, does
not guarantee channel access before a finite deadline. The well-known property
of CSMA is undesirable for critical communications scenarios. The simulation
results reveal that a specific vehicle is forced to drop over 80% of its
packets because no channel access was possible before the next message was
generated. To overcome this problem, we propose to use STDMA for real-time data
traffic between vehicles. The real- time properties of STDMA are investigated
by means of the highway road simulation scenario, with promising results.


title: Geometric Ruzsa triangle inequality in metric spaces with dilations

abstract:
  The Appendix of the article arXiv:1212.5056 [math.CO] "On growth in an
abstract plane" by Nick Gill, H. A. Helfgott, Misha Rudnev, contains a general
"geometric Ruzsa triangle inequality" in a Desarguesian projective plane. The
purpose of this note is to give a similar inequality for metric spaces with
dilations, that is in the absence of an algebraic or incidence structure.


title: On the local convexity of intersection bodies of revolution

abstract:
  One of the fundamental results in Convex Geometry is Busemann's theorem,
which states that the intersection body of a symmetric convex body is convex.
Thus, it is only natural to ask if there is a quantitative version of
Busemann's theorem, i.e., if the intersection body operation actually improves
convexity. In this paper we concentrate on the symmetric bodies of revolution
to provide several results on the (strict) improvement of convexity under the
intersection body operation. It is shown that the intersection body of a
symmetric convex body of revolution has the same asymptotic behavior near the
equator as the Euclidean ball. We apply this result to show that in
sufficiently high dimension the double intersection body of a symmetric convex
body of revolution is very close to an ellipsoid in the Banach-Mazur distance.
We also prove results on the local convexity at the equator of intersection
bodies in the class of star bodies of revolution.


title: Hamilton-Jacobi theory in k-cosymplectic field theories

abstract:
  In this paper we extend the geometric formalism of the Hamilton-Jacobi theory
for time dependent Mechanics to the case of classical field theories in the
k-cosymplectic framework.


title:
Electronic structure of KTi(SO4)2.H2O - a S=1/2 frustrated chain
  antiferromagnet

abstract:
  The compound KTi(SO4)2.H2O was recently reported as a quasi one-dimensional
spin 1/2 compound with competing antiferromagnetic nearest neighbor exchange J1
and next-nearest neighbor exchange J2 along the chain with a frustration ratio
alpha = J2/J1 ~ 0.29 [Chem. Mater. vol. 20, pg. 8 (2008)]. Here, we report a
microscopically based magnetic model for this compound derived from density
functional electronic structure calculations along with respective
tight-binding models. Our calculations confirm the quasi one-dimensional nature
of the system with antiferromagnetic J1 and J2, but suggest a significantly
larger frustration ratio alpha ~ 1.1 +- 0.2. Based on transfer matrix
renormalization group calculations we found that, due to an intrinsic symmetry
of the J1-J2 model, our larger frustration ratio alpha is also consistent with
the previous thermodynamic data. To resolve this issue, we propose performing
high-field magnetization measurements and low temperature susceptibility
measurements which should allow to precisely identify the frustration ratio
alpha.


title: Evolution of Swarm Robotics Systems with Novelty Search

abstract:
  Novelty search is a recent artificial evolution technique that challenges
traditional evolutionary approaches. In novelty search, solutions are rewarded
based on their novelty, rather than their quality with respect to a predefined
objective. The lack of a predefined objective precludes premature convergence
caused by a deceptive fitness function. In this paper, we apply novelty search
combined with NEAT to the evolution of neural controllers for homogeneous
swarms of robots. Our empirical study is conducted in simulation, and we use a
common swarm robotics task - aggregation, and a more challenging task - sharing
of an energy recharging station. Our results show that novelty search is
unaffected by deception, is notably effective in bootstrapping the evolution,
can find solutions with lower complexity than fitness-based evolution, and can
find a broad diversity of solutions for the same task. Even in non-deceptive
setups, novelty search achieves solution qualities similar to those obtained in
traditional fitness-based evolution. Our study also encompasses variants of
novelty search that work in concert with fitness-based evolution to combine the
exploratory character of novelty search with the exploitatory character of
objective-based evolution. We show that these variants can further improve the
performance of novelty search. Overall, our study shows that novelty search is
a promising alternative for the evolution of controllers for robotic swarms.


title: On the B*' --> B transition

abstract:
  We present a first Nf=2 lattice estimate of the hadronic coupling g_12 which
parametrises the strong decay of a radially excited B* meson into the ground
state B meson at zero recoil. We work in the static limit of Heavy Quark
Effective Theory (HQET) and solve a Generalised Eigenvalue Problem (GEVP),
which is necessary for the extraction of excited state properties. After an
extrapolation to the continuum limit and a check of the pion mass dependence,
we obtain g_12 = -0.17(4).


title:
On the periodic solutions of a rigid Dumbbell satellite in a circular
  orbit

abstract:
  The aim of the present paper is to provide suficient conditions for the
existence of periodic solutions of the perturbed attitude dynamics of a rigid
dumbbell satellite in a circular orbit.


title: Towards a better approximation for sparsest cut?

abstract:
  We give a new $(1+\epsilon)$-approximation for sparsest cut problem on graphs
where small sets expand significantly more than the sparsest cut (sets of size
$n/r$ expand by a factor $\sqrt{\log n\log r}$ bigger, for some small $r$; this
condition holds for many natural graph families). We give two different
algorithms. One involves Guruswami-Sinop rounding on the level-$r$ Lasserre
relaxation. The other is combinatorial and involves a new notion called {\em
Small Set Expander Flows} (inspired by the {\em expander flows} of ARV) which
we show exists in the input graph. Both algorithms run in time $2^{O(r)}
\mathrm{poly}(n)$. We also show similar approximation algorithms in graphs with
genus $g$ with an analogous local expansion condition. This is the first
algorithm we know of that achieves $(1+\epsilon)$-approximation on such general
family of graphs.


title: Induced representations and harmonic analysis on finite groups

abstract:
  Given a finite group $G$ and a subgroup $K$, we study the commutant of
$\text{Ind}_K^G\theta$, where $\theta$ is an irreducible $K$-representation.
After a careful analysis of Frobenius reciprocity, we are able to introduce an
orthogonal basis in such commutant and an associated Fourier transform. Then we
translate our results in the corresponding Hecke algebra, an isomorphic algebra
in the group algebra of $G$. Again a complete Fourier analysis is developed
and, as particular cases, we obtain some results of Curtis and Fossum on the
irreducible characters of Hecke algebras. Finally, we develop a theory of
Gelfand-Tsetlin bases for Hecke algebras.


title:
Analysis of a rate-adaptive reconciliation protocol and the effect of
  the leakage on the secret key rate

abstract:
  Quantum key distribution performs the trick of growing a secret key in two
distant places connected by a quantum channel. The main reason is that the
legitimate users can bound the information gathered by the eavesdropper. In
practical systems, whether because of finite resources or external conditions,
the quantum channel is subject to fluctuations. A rate adaptive information
reconciliation protocol, that adapts to the changes in the communication
channel, is then required to minimize the leakage of information in the
classical postprocessing.
  We consider here the leakage of a rate-adaptive information reconciliation
protocol. The length of the exchanged messages is larger than that of an
optimal protocol; however, we prove that the min-entropy reduction is limited.
The simulation results, both on the asymptotic and in the finite-length regime,
show that this protocol allows to increase the amount of distillable secret
key.


title:
Constraining the neutron-proton effective mass splitting using empirical
  constraints on the density dependence of nuclear symmetry energy around
  normal density

abstract:
  According to the Hugenholtz-Van Hove theorem, nuclear symmetry energy \esym
and its slope \lr at an arbitrary density $\rho$ are determined by the nucleon
isovector (symmetry) potential \usym and its momentum dependence
$\frac{\partial U_{sym}}{\partial k}$. The latter determines uniquely the
neutron-proton effective k-mass splitting $m^*_{n-p}(\rho,\delta)\equiv (m_{\rm
n}^*-m_{\rm p}^*)/m$ in neutron-rich nucleonic matter of isospin asymmetry
$\delta$. Using currently available constraints on the \es0 and \l0 at normal
density $\rho_0$ of nuclear matter from 28 recent analyses of various
terrestrial nuclear laboratory experiments and astrophysical observations, we
try to infer the corresponding neutron-proton effective k-mass splitting
$m^*_{n-p}(\rho_0,\delta)$. While the mean values of the
$m^*_{n-p}(\rho_0,\delta)$ obtained from most of the studies are remarkably
consistent with each other and scatter very closely around an empirical value
of \emass$=0.27\cdot\delta$, it is currently not possible to scientifically
state surely that the \emass is positive within the present knowledge of the
uncertainties. Quantifying, better understanding and then further reducing the
uncertainties using modern statistical and computational techniques in
extracting the \es0 and \l0 from analyzing the experimental data are much
needed.


title: A Bayesian view of the Higgs sector with higher dimensional operators

abstract:
  We investigate the possibilities of New Physics affecting the Standard Model
(SM) Higgs sector. An effective Lagrangian with dimension-six operators is used
to capture the effect of New Physics. We carry out a global Bayesian inference
analysis, considering the recent LHC data set including all available
correlations, as well as results from Tevatron. Trilinear gauge boson couplings
and electroweak precision observables are also taken into account. The case of
weak bosons tensorial couplings is closely examined and NLO QCD corrections are
taken into account in the deviations we predict. We consider two scenarios, one
where the coefficients of all the dimension-six operators are essentially
unconstrained, and one where a certain subset is loop suppressed. In both
scenarios, we find that large deviations from some of the SM Higgs couplings
can still be present, assuming New Physics arising at 3 TeV. In particular, we
find that a significantly reduced coupling of the Higgs to the top quark is
possible and slightly favored by searches on Higgs production in association
with top quark pairs. The total width of the Higgs boson is only weakly
constrained and can vary between 0.7 and 2.7 times the Standard Model value
within 95% Bayesian credible interval (BCI). We also observe sizeable effects
induced by New Physics contributions to tensorial couplings. In particular, the
Higgs boson decay width into $Z\gamma$ can be enhanced by up to a factor 12
within 95% BCI.


title: Topological properties of a time-integrated activity driven network

abstract:
  Here we consider the topological properties of the integrated networks
emerging from the activity driven model [Perra at al. Sci. Rep. 2, 469 (2012)],
a temporal network model recently proposed to explain the power-law degree
distribution empirically observed in many real social networks. By means of a
mapping to a hidden variables network model, we provide analytical expressions
for the main topological properties of the integrated network, depending on the
integration time and the distribution of activity potential characterizing the
model. The expressions obtained, exacts in some cases, the results of
controlled asymptotic expansions in others, are confirmed by means of extensive
numerical simulations. Our analytical approach, which highlights the
differences of the model with respect to the empirical observations made in
real social networks, can be easily extended to deal with improved, more
realistic modifications of the activity driven network paradigm.


title:
Non-decoupling SUSY in LFV Higgs decays: a window to new physics at the
  LHC

abstract:
  The recent discovery of a SM-like Higgs boson at the LHC, with a mass around
125-126 GeV, together with the absence of results in the direct searches for
supersymmetry, is pushing the SUSY scale ($m_\text{SUSY}$) into the multi-TeV
range. This discouraging situation from a low-energy SUSY point of view has its
counterpart in indirect SUSY observables which present a non-decoupling
behavior with $m_\text{SUSY}$. This is the case of the one-loop lepton flavor
violating Higgs decay rates induced by SUSY, which are shown here to remain
constant as $m_\text{SUSY}$ grows, for large $m_\text{SUSY} >$ 2 TeV values and
for all classes of intergenerational mixing in the slepton sector, $LL$, $LR$,
$RL$ and $RR$. In this work we focus on the LFV decays of the three neutral
MSSM Higgs bosons $h$, $H$, $A \to \tau \mu$, considering the four types of
slepton mixing ($\delta_{23}^{LL}$, $\delta_{23}^{LR}$, $\delta_{23}^{RL}$,
$\delta_{23}^{RR}$), and show that all the three channels could be measurable
at the LHC, being $h \to \tau \mu$ the most promising one, with up to about
hundred of events expected with the current LHC center-of-mass energy and
luminosity. The most promising predictions for the future LHC stage are also
included.


title:
The Curse of Dimensionality for Numerical Integration of Smooth
  Functions II

abstract:
  We prove the curse of dimensionality in the worst case setting for numerical
integration for a number of classes of smooth $d$-variate functions. Roughly
speaking, we consider different bounds for the derivatives of $f \in C^k(D_d)$
and ask whether the curse of dimensionality holds for the respective classes of
functions. We always assume that $D_d \subset \mathbb{R}^d$ has volume one and
consider various values of $k$ including the case $k=\infty$ which corresponds
to infinitely many differentiable functions. We obtain necessary and sufficient
conditions, and in some cases a full characterization for the curse of
dimensionality. For infinitely many differentiable functions we prove the curse
if the bounds on the successive derivatives are appropriately large. The proof
technique is based on a volume estimate of a neighborhood of the convex hull of
$n$ points which decays exponentially fast if $n$ is small relative to $d$. For
$k=\infty$, we also also study conditions for quasi-polynomial, weak and
uniform weak tractability.


title: Subgroups which admit extensions of homomorphisms

abstract:
  We classify by numerical invariants the finite subgroups $H$ of a primary
abelian group $G$ for which every homomorphism or monomorphism of $H$ into $G$,
or every endomorphism of $H$, extends to an endomorphism of $G$. We apply these
results to show that for finitely generated subgroups of general abelian
groups, the extendibility of monomorphisms implies the extendibility of all
homomorphisms.


title:
POPSTAR Evolutionary Synthesis Models III: Photometric properties of
  young star clusters and mixed populations

abstract:
  This is the third paper of a series reporting the results from the POPSTAR
evolutionary synthesis models. The main goal of this work is to present and
discuss the synthetic photometric properties of Single Stellar Populations
(SSPs) resulting from our POPSTAR code. Colours in the Johnson and SDSS
systems, halpha and hbeta luminosities and equivalent widths, and ionising
region size, have been computed for a wide range of metallicity (Z = 0.0001 -
0.05) and age (0.1 Myr to 20 Gyr). We demonstrate the importance of the
contribution of emission lines to broader-band photometry when characterising
stellar populations, through the presentation of both contaminated and
non-contaminated colours (in both the Johnson and SDSS systems). The tabulated
colours include stellar and nebular components, in addition to line emission.
The main application of these models is the determination of physical
properties of a given young ionising cluster, when only photometric
observations are available; for an isolated star forming region, the young star
cluster models can be used, free from the contamination of any underlying
background stellar population. In most cases, however, the ionising population
is usually embedded in a large and complex system, and the observed photometric
properties result from the combination of a young star-forming burst and the
underlying older population of the host. Therefore, the second objective of
this paper is to provide a grid of models useful in the interpretation of mixed
regions where the separation of young and old populations is not sufficiently
reliable. We describe the set of PopStar Spectral Energy Distributions, the
derived colours and other photometric parameters, for mixed populations where
an underlying host population is combined in different mass ratios with a
recent ionising burst.


title:
Degree distribution and scaling in the Connecting Nearest Neighbors
  model

abstract:
  We present a detailed analysis of the Connecting Nearest Neighbors (CNN)
model by V\'azquez. We show that the degree distribution follows a power law,
but the scaling exponent can vary with the parameter setting. Moreover, the
correspondence of the growing version of the Connecting Nearest Neighbors
(GCNN) model to the particular random walk model (PRW model) and recursive
search model (RS model) is established.


title:
SRG/eROSITA prospects for the detection of stellar tidal disruption
  flares

abstract:
  We discuss the potential of the eROSITA telescope on board the
Spectrum-Roentgen-Gamma (SRG) observatory to detect stellar tidal disruption
events (TDE) during its 4-year all-sky survey. These events are expected to
reveal themselves as luminous flares of UV/soft X-ray emission associated with
the centres of previously non-active galaxies and fading by few orders of
magnitude on time-scales of several months to years. Given that eROSITA will
complete an all-sky survey every 6 months and a total of 8 such scans will be
performed over the course of the mission, we propose to distinguish TDEs from
other X-ray transients using two criteria: I) large (more than a factor of 10)
X-ray variation between two subsequent 6-month scans and ii) soft X-ray
spectrum. The expected number of TDE candidates is $\sim 10^3$ per scan (with
most of the events being new discoveries in a given scan), so that a total of
several thousand TDE candidates could be found during the 4-year survey. The
actual number may significantly differ from this estimate, since it is based on
just a few TDEs observed so far. The eROSITA all-sky survey is expected to be
nearly equally sensitive to TDEs occurring near supermassive black holes (SMBH)
of mass between $\sim 10^6$ and $\sim 10^7 M_\odot$ and will thus provide a
unique census of quiescent SMBHs and associated nuclear stellar cusps in the
local Universe ($z\lesssim 0.15$). Information on TDE candidates will be
available within a day after their detection and localization by eROSITA,
making possible follow-up observations that may reveal peculiar types of TDEs.


title: On Hamiltonian flows whose orbits are straight lines

abstract:
  We consider real analytic Hamiltonians whose flow depends linearly on time.
Trivial examples are Hamiltonians $H(q,p)$ that do not depend on the coordinate
$q$. By a theorem of Moser, every polynomial Hamiltonian of degree 3 reduces to
such a $q$-independent Hamiltonian via a linear symplectic change of variables.
We show that such a reduction is impossible, in general, for polynomials of
degree 4 or higher. But we give a condition that implies linear-symplectic
conjugacy to another simple class of Hamiltonians. The condition is shown to
hold for all nondegenerate Hamiltonians that are homogeneous of degree 4.


title: Nonparametric Bayesian testing for monotonicity

abstract:
  This paper studies the problem of testing whether a function is monotone from
a nonparametric Bayesian perspective. Two new families of tests are
constructed. The first uses constrained smoothing splines, together with a
hierarchical stochastic-process prior that explicitly controls the prior
probability of monotonicity. The second uses regression splines, together with
two proposals for the prior over the regression coefficients. The finite-sample
performance of the tests is shown via simulation to improve upon existing
frequentist and Bayesian methods. The asymptotic properties of the Bayes factor
for comparing monotone versus non-monotone regression functions in a Gaussian
model are also studied. Our results significantly extend those currently
available, which chiefly focus on determining the dimension of a parametric
linear model.


title:
Nonlinear excitation of acoustic modes by large amplitude Alfv\'en waves
  in a laboratory plasma

abstract:
  The nonlinear three-wave interaction process at the heart of the parametric
decay process is studied by launching counter-propagating Alfv\'en waves from
antennas placed at either end of the Large Plasma Device (LAPD). A resonance in
the beat wave response produced by the two launched Alfv\'en waves is observed
and is identified as a damped ion acoustic mode based on the measured
dispersion relation. Other properties of the interaction including the spatial
profile of the beat mode and response amplitude are also consistent with
theoretical predictions for a three-wave interaction driven by a non-linear
pondermotive force.


title:
An explicit solution for implicit time stepping in finite strain
  viscoelasticity

abstract:
  We consider the numerical treatment of one of the most popular finite strain
models of the viscoelastic Maxwell body. This model is based on the
multiplicative decomposition of the deformation gradient, combined with
Neo-Hookean hyperelastic relations between stresses and elastic strains. The
evolution equation is six dimensional. For the corresponding local initial
value problem, a fully implicit integration procedure is considered, and a
simple explicit update formula is derived. Thus, no local iterative procedure
is required, which makes the numerical scheme more robust and efficient. The
resulting integration algorithm is unconditionally stable and first order
accurate. The incompressibility constraint of the inelastic flow is exactly
preserved. A rigorous proof of the symmetry of the consistent tangent operator
is provided. Moreover, some properties of the numerical solution, like
invariance under the change of the reference configuration and positive energy
dissipation within a time step, are discussed. Numerical tests show that, in
terms of accuracy, the proposed integration algorithm is equivalent to the
classical implicit scheme based on the exponential mapping. Finally, in order
to check the stability of the algorithm numerically, a representative initial
boundary value problem involving finite viscoelastic deformations is
considered. An FEM solution of the representative problem using MSC.MARC is
presented.


title: Life Before Earth

abstract:
  An extrapolation of the genetic complexity of organisms to earlier times
suggests that life began before the Earth was formed. Life may have started
from systems with single heritable elements that are functionally equivalent to
a nucleotide. The genetic complexity, roughly measured by the number of
non-redundant functional nucleotides, is expected to have grown exponentially
due to several positive feedback factors: gene cooperation, duplication of
genes with their subsequent specialization, and emergence of novel functional
niches associated with existing genes. Linear regression of genetic complexity
on a log scale extrapolated back to just one base pair suggests the time of the
origin of life 9.7 billion years ago. This cosmic time scale for the evolution
of life has important consequences: life took ca. 5 billion years to reach the
complexity of bacteria; the environments in which life originated and evolved
to the prokaryote stage may have been quite different from those envisaged on
Earth; there was no intelligent life in our universe prior to the origin of
Earth, thus Earth could not have been deliberately seeded with life by
intelligent aliens; Earth was seeded by panspermia; experimental replication of
the origin of life from scratch may have to emulate many cumulative rare
events; and the Drake equation for guesstimating the number of civilizations in
the universe is likely wrong, as intelligent life has just begun appearing in
our universe. Evolution of advanced organisms has accelerated via development
of additional information-processing systems: epigenetic memory, primitive
mind, multicellular brain, language, books, computers, and Internet. As a
result the doubling time of complexity has reached ca. 20 years. Finally, we
discuss the issue of the predicted technological singularity and give a
biosemiotics perspective on the increase of complexity.


title:
Analytical self-dual solutions in a nonstandard Yang-Mills-Higgs
  scenario

abstract:
  We have found analytical self-dual solutions within the generalized
Yang-Mills-Higgs model introduced in Phys. Rev. D 86, 085034 (2012). Such
solutions are magnetic monopoles satisfying Bogomol'nyi-Prasad-Sommerfield
(BPS) equations and usual finite energy boundary conditions. Moreover, the new
solutions are classified in two different types according to their capability
of recovering (or not) the usual 't Hooft--Polyakov monopole. Finally, we
compare the profiles of the solutions we found with the standard ones, from
which we comment about the main features exhibited by the new configurations.


title:
Heavy quarkonium production in the Regge limit of QCD: from Tevatron to
  LHC

abstract:
  Heavy quarkonium production in the framework of the non-relativistic quantum
chromodynamics and leading order of the parton Reggeization approach at the
Tevatron and LHC is discussed. In this note, we compare our predictions for the
bottomonium production at the LHC due to the color-singlet approximation of the
non-relativistic quantum chromodynamics with CMS and LHCb data. It is found,
that in the production of Upsilon(1S) states, the color-singlet mechanism is
dominating, whereas to describe the data for the inclusive Upsilon(2S) and
Upsilon(3S) production, the color- octet contributions should be taken into
account.


title:
Black Hole-Neutron Star Mergers with a Hot Nuclear Equation of State:
  Outflow and Neutrino-Cooled Disk for a Low-Mass, High-Spin Case

abstract:
  Neutrino emission significantly affects the evolution of the accretion tori
formed in black hole-neutron star mergers. It removes energy from the disk,
alters its composition, and provides a potential power source for a gamma-ray
burst. To study these effects, simulations in general relativity with a hot
microphysical equation of state and neutrino feedback are needed. We present
the first such simulation, using a neutrino leakage scheme for cooling to
capture the most essential effects and considering a moderate mass (1.4
M_{\odot} neutron star, 5.6 M_{\odot} black hole), high spin (black hole
J/M^2=0.9) system with the K_0=220 MeV Lattimer-Swesty equation of state. We
find that about 0.08 M_{\odot} of nuclear matter is ejected from the system,
while another 0.3 M_{\odot} forms a hot, compact accretion disk. The primary
effects of the escaping neutrinos are (i) to make the disk much denser and more
compact, (ii) to cause the average electron fraction Y_e of the disk to rise to
about 0.2 and then gradually decrease again, and (iii) to gradually cool the
disk. The disk is initially hot (T~6 MeV) and luminous in neutrinos
(L_{\nu}~10^{54} erg s^{-1}), but the neutrino luminosity decreases by an order
of magnitude over 50 ms of post-merger evolution.


title: Infinitesimal rigidity for non-Euclidean bar-joint frameworks

abstract:
  The minimal infinitesimal rigidity of bar-joint frameworks in the
non-Euclidean spaces (R^2, ||.||_q) are characterised in terms of (2,2)-tight
graphs. Specifically, a generically placed bar-joint framework (G,p) in the
plane is minimally infinitesimally rigid with respect to a non-Euclidean l^q
norm if and only if the underlying graph G = (V,E) contains 2|V|-2 edges and
every subgraph H=(V(H),E(H)) contains at most 2|V(H)|-2 edges.


title: Vortices and the Abel-Jacobi map

abstract:
  The abelian Higgs model on a compact Riemann surface \Sigma supports vortex
solutions for any positive vortex number d \in \ZZ. Moreover, the vortex moduli
space for fixed d has long been known to be the symmetrized d-th power of
\Sigma, in symbols, \Sym^d(\Sigma). This moduli space is Kahler with respect to
the physically motivated metric whose geodesics describe slow vortex motion.
  In this paper we appeal to classical properties of \Sym^d(\Sigma) to obtain
new results for the moduli space metric. Our main tool is the Abel-Jacobi map,
which maps \Sym^d(\Sigma) into the Jacobian of \Sigma. Fibres of the
Abel-Jacobi map are complex projective spaces, and the first theorem we prove
states that near the Bradlow limit the moduli space metric restricted to these
fibres is a multiple of the Fubini-Study metric. Additional significance is
given to the fibres of the Abel-Jacobi map by our second result: we show that
if \Sigma is a hyperelliptic surface, there exist two special fibres which are
geodesic submanifolds of the moduli space. Even more is true: the Abel-Jacobi
map has a number of fibres which contain complex projective subspaces that are
geodesic.


title:
X-ray photon detection using superconducting resonators in thermal
  quasi-equilibrium

abstract:
  Superconducting resonators have to date been used for photon detection in a
non-equilibrium manner. In this paper, we demonstrate that such devices can
also be used in a thermal quasi-equilibrium manner to detect X-ray photons. We
have used a resonator to measure the temperature rise induced by an X-ray
photon absorbed in normal metal and superconducting absorbers on continuous and
perforated silicon nitride membranes. We observed two distinct pulses with
vastly different decay times. We attribute the shorter pulses to
non-equilibrium quasiparticle relaxation and the longer pulses to a thermal
relaxation process. In addition, we have measured the temperature dependence of
the X-ray induced temperature rise and decay times. Finally, we have measured
the resonator sensitivity and energy resolution. Superconducting resonators
used in a thermal quasi-equilibrium manner have the potential to be used for
X-ray microcalorimetry.


title: Fibonacci Numbers and Identities II

abstract:
  We give alternative proof of Melham's and Howard's identities on generalised
Fibonacci numbers


title:
Existence of weak solutions to some stationary Schr\"odinger equations
  with singular nonlinearity

abstract:
  We prove some existence (and sometimes also uniqueness) of weak solutions to
some stationary equations associated to the complex Schr\"{o}dinger operator
under the presence of a singular nonlinear term. Among other new facts, with
respect some previous results in the literature for such type of nonlinear
potential terms, we include the case in which the spatial domain is possibly
unbounded (something which is connected with some previous localization results
by the authors), the presence of possible non-local terms at the equation, the
case of boundary conditions different to the Dirichlet ones and, finally, the
proof of the existence of solutions when the right-hand side term of the
equation is beyond the usual $L^2$-space.


title: Quipper: A Scalable Quantum Programming Language

abstract:
  The field of quantum algorithms is vibrant. Still, there is currently a lack
of programming languages for describing quantum computation on a practical
scale, i.e., not just at the level of toy problems. We address this issue by
introducing Quipper, a scalable, expressive, functional, higher-order quantum
programming language. Quipper has been used to program a diverse set of
non-trivial quantum algorithms, and can generate quantum gate representations
using trillions of gates. It is geared towards a model of computation that uses
a classical computer to control a quantum device, but is not dependent on any
particular model of quantum hardware. Quipper has proven effective and easy to
use, and opens the door towards using formal methods to analyze quantum
algorithms.


title: Intensity interferometry with more than two detectors?

abstract:
  The original intensity interferometers were instruments built in the 1950s
and 60s by Hanbury Brown and collaborators, achieving milli-arcsec resolutions
in visible light without optical-quality mirrors. They exploited a then-novel
physical effect, now known as HBT correlation after the experiments of Hanbury
Brown and Twiss, and nowadays considered fundamental in quantum optics. Now a
new generation of inten- sity interferometers is being designed, raising the
possibility of measuring intensity correlations with three or more detectors.
Quantum optics predicts some interesting features in higher-order HBT. One is
that HBT correlation increases combinatorially with the number of detectors.
Signal to noise considerations suggest, that many-detector HBT correlations
would be mea- surable for bright masers, but very difficult for thermal
sources. But the more modest three-detector HBT correlation seems measurable
for bright stars, and would provide image information (namely the bispectrum)
not present in standard HBT.


title: Localization and dimension free estimates for maximal functions

abstract:
  In the recent paper [J. Funct. Anal. {\bf 259} (2010)], Naor and Tao
introduce a new class of measures with a so-called micro-doubling property and
present, via martingale theory and probability methods, a localization theorem
for the associated maximal functions. As a consequence they obtain a weak type
estimate in a general abstract setting for these maximal functions that is
reminiscent of the `$n\log n$ result' of Stein and Str\"omberg in Euclidean
spaces.
  The purpose of this work is twofold. First we introduce a new localization
principle that localizes not only in the time-dilation parameter but also in
space. The proof uses standard covering lemmas and selection processes. Second,
we show that a uniform condition for micro-doubling in the Euclidean spaces
provides indeed dimension free estimates for their maximal functions in all
$L^p$ with $p>1$. This is done introducing a new technique that allows to
differentiate through dimensions.


title: Generic Behaviour Similarity Measures for Evolutionary Swarm Robotics

abstract:
  Novelty search has shown to be a promising approach for the evolution of
controllers for swarm robotics. In existing studies, however, the experimenter
had to craft a domain dependent behaviour similarity measure to use novelty
search in swarm robotics applications. The reliance on hand-crafted similarity
measures places an additional burden to the experimenter and introduces a bias
in the evolutionary process. In this paper, we propose and compare two
task-independent, generic behaviour similarity measures: combined state count
and sampled average state. The proposed measures use the values of sensors and
effectors recorded for each individual robot of the swarm. The characterisation
of the group-level behaviour is then obtained by combining the sensor-effector
values from all the robots. We evaluate the proposed measures in an aggregation
task and in a resource sharing task. We show that the generic measures match
the performance of domain dependent measures in terms of solution quality. Our
results indicate that the proposed generic measures operate as effective
behaviour similarity measures, and that it is possible to leverage the benefits
of novelty search without having to craft domain specific similarity measures.


title:
Limiting spectral distribution for Wigner matrices with dependent
  entries

abstract:
  In this article we show the existence of limiting spectral distribution of a
symmetric random matrix whose entries come from a stationary Gaussian process
with covariances satisfying a summability condition. We provide an explicit
description of the moments of the limiting measure. We also show that in some
special cases the Gaussian assumption can be relaxed. The description of the
limiting measure can also be made via its Stieltjes transform which is
characterized as the solution of a functional equation. In two special cases,
we get a description of the limiting measure - one as a free product
convolution of two distributions, and the other one as a dilation of the Wigner
semicircular law.


title:
Evolution with size in a locally periodic system: Scattering and
  deterministic maps

abstract:
  In this paper we study the evolution of the wave function with the system
size in a locally periodic structure. In particular we analyse the dependence
of the wave function with the number of unit cells, which also reflects
information about its spatial behaviour in the system. We reduce the problem to
a nonlinear map and find an equivalence of its energy regions of single
periodicity and of weak chaos, with the forbidden and allowed bands of the
fully periodic system, respectively. At finite size the wave function decays
exponentially with system size, as well as in space, when the energy lies
inside a region of single periodicity, while for energies in the weak chaotic
region never decays. At the transition between those regions the wave function
still decays but in a $q$-exponential form; we found that the decay length is a
half of the mean free path, which is larger than the lattice constant.


title:
Validated Real Time Middle Ware For Distributed Cyber Physical Systems
  Using HMM

abstract:
  Distributed Cyber Physical Systems designed for different scenario must be
capable enough to perform in an efficient manner in every situation. Earlier
approaches, such as CORBA, has performed but with different time constraints.
Therefore, there was the need to design reconfigurable, robust, validated and
consistent real time middle ware systems with end-to-end timing. In the
DCPS-HMM we have proposed the processor efficiency and data validation which
may proof crucial in implementing various distributed systems such as credit
card systems or file transfer through network.


title: Retrograde versus prograde models of accreting black holes

abstract:
  There is a general consensus that magnetic fields, accretion disks, and
rotating black holes are instrumental in the generation of the most powerful
sources of energy in the known universe. Nonetheless, because magnetized
accretion onto rotating black holes involves both the complications of
nonlinear magnetohydrodynamics that currently cannot fully be treated
numerically, and uncertainties about the origin of magnetic fields that at
present are part of the input, the space of possible solutions remains less
constrained. Consequently, the literature still bears witness to the
proliferation of rather different black hole engine models. But the accumulated
wealth of observational data is now sufficient to meaningfully distinguish
between them. It is in this light that this critical paper compares the recent
retrograde framework with standard "spin paradigm" prograde models.


title: Strong Subadditivity, Null Energy Condition and Charged Black Holes

abstract:
  Using the Hubeny-Rangamani-Takayanagi (HRT) conjectured formula for
entanglement entropy in the context of the AdS/CFT correspondence with
time-dependent backgrounds, we investigate the relation between the bulk null
energy condition (NEC) of the stress-energy tensor with the strong
sub-additivity (SSA) property of entanglement entropy in the boundary theory.
In a background that interpolates between an AdS to an
AdS-Reissner-Nordstrom-type geometry, we find that generically there always
exists a critical surface beyond which the violation of NEC would naively
occur. However, the extremal area surfaces that determine the entanglement
entropy for the boundary theory, can penetrate into this forbidden region only
for certain choices for the mass and the charge functions in the background.
This penetration is then perceived as the violation of SSA in the boundary
theory. We also find that this happens only when the critical surface lies
above the apparent horizon, but not otherwise. We conjecture that SSA, which is
thus non-trivially related to NEC, also characterizes the entire time-evolution
process along which the dual field theory may thermalize.


title: Universal Behavior for Bond Percolation

abstract:
  We collect together results for bond percolation on various lattices from two
to fourteen dimensions which, in the limit of large dimension $d$ or number of
neighbors $z$, smoothly approach a randomly diluted Erd\H{o}s-R\'enyi graph. We
include new results on bond diluted hyper-sphere packs in up to nine
dimensions, which show the mean coordination, excess kurtosis and skewness
evolving smoothly with dimension towards the Erd\H{o}s-R\'enyi limit.


title: Distinguishing Spin Relaxation Mechanisms in Organic Semiconductors

abstract:
  A theory is introduced for spin relaxation and spin diffusion of hopping
carriers in a disordered system. For disorder described by a distribution of
waiting times between hops (e.g. from multiple traps, site-energy disorder
and/or positional disorder) the dominant spin relaxation mechanisms in organic
semiconductors (hyperfine, hopping-induced spin-orbit, and intra-site spin
relaxation) each produce different characteristic spin relaxation and spin
diffusion dependences on temperature. The resulting unique experimental
signatures predicted by the theory for each mechanism in organic semiconductors
provide a prescription for determining the dominant spin relaxation mechanism.


title: Dynamical evolution of black hole sub-systems in idealised star clusters

abstract:
  In this paper, globular star clusters which contain a sub-system of
stellar-mass black holes (BH) are investigated. This is done by considering
two-component models, as these are the simplest approximation of more realistic
multi-mass systems, where one component represents the BH population and the
other represents all the other stars. These systems are found to undergo a long
phase of evolution where the centre of the system is dominated by a dense BH
sub-system. After mass segregation has driven most of the BH into a compact
sub-system, the evolution of the BH sub-system is found to be influenced by the
cluster in which it is contained. The BH sub-system evolves in such a way as to
satisfy the energy demands of the whole cluster, just as the core of a one
component system must satisfy the energy demands of the whole cluster. The BH
sub-system is found to exist for a significant amount of time. It takes
approximately 10t_{rh,i}, where t_{rh,i} is the initial half-mass relaxation
time, from the formation of the compact BH sub-system up until the time when
90% of the sub-system total mass is lost (which is of order 10^{3} times the
half-mass relaxation time of the BH sub-system at its time of formation). Based
on theoretical arguments the rate of mass loss from the BH sub-system
(\dot{M}_2) is predicted to be -(beta*zeta*M)/(alpha*t_{rh}), where M is the
total mass, t_{rh} is the half-mass relaxation time, and alpha, beta, zeta are
three dimensionless parameters (see Section 2 for details). An interesting
consequence of this is that the rate of mass loss from the BH sub-system is
approximately independent of the stellar mass ratio (m_2/m_1) and the total
mass ratio (M_2/M_1) (in the range m_2/m_1 >~ 10 and M_2/M_1 ~ 10^{-2}, where
m_1, m_2 are the masses of individual low-mass and high-mass particles
respectively, and M_1, M_2 are the corresponding total masses).


title: On the Average Number of Edges in Theta Graphs

abstract:
  Theta graphs are important geometric graphs that have many applications,
including wireless networking, motion planning, real-time animation, and
minimum-spanning tree construction. We give closed form expressions for the
average degree of theta graphs of a homogeneous Poisson point process over the
plane. We then show that essentially the same bounds---with vanishing error
terms---hold for theta graphs of finite sets of points that are uniformly
distributed in a square. Finally, we show that the number of edges in a theta
graph of points uniformly distributed in a square is concentrated around its
expected value.


title:
Initial state geometry and the role of hydrodynamics in proton-proton,
  proton-nucleus and deuteron-nucleus collisions

abstract:
  We apply the successful Monte Carlo Glauber and IP-Glasma initial state
models of heavy ion collisions to the much smaller size systems produced in
proton-proton, proton-nucleus and deuteron- nucleus collisions. We observe a
significantly greater sensitivity of the initial state geometry to details of
multi-particle production in these models compared to nucleus-nucleus
collisions. In particular, we find that the size of the system produced in p+A
collisions is very similar to the one produced in p+p collisions, and predict
comparable Hanbury-Brown-Twiss radii in the absence of flow in both systems.
Differences in the eccentricities computed in the models are large, while
differences amongst the generated flow coefficients v_2 and v_3 are smaller.
For a large number of participants in proton-lead collisions, the v_2 generated
in the IP-Glasma model is comparable to the value obtained in proton-proton
collisions. Viscous corrections to flow are large over characteristic lifetimes
in the smaller size systems. In contrast, viscous contributions are
significantly diminished over the longer space-time evolution of a heavy ion
collision.


title: Probing the pattern of holographic thermalization with photons

abstract:
  We investigate the behavior of the retarded Green's function of a U(1) gauge
field in holographic N=4 Super Yang-Mills plasma, taking the leading strong
coupling corrections into account. First, we use the thermal limit of this
quantity to determine the flow of the photon quasinormal mode spectrum away
from the infinite 't Hooft coupling limit, and after this specialize to a
specific model of holographic thermalization, in which we evaluate the
corresponding spectral density. In the latter case, our primary interest lies
in the pattern, with which the spectral density approaches its equilibrium
form, and how this process depends on the value of the coupling as well as the
photon virtuality. All of the results obtained point consistently towards the
weakening of the usual top/down pattern of holographic thermalization, once the
coupling is decreased from the \lambda=infinity limit.


title:
Do Social Explanations Work? Studying and Modeling the Effects of Social
  Explanations in Recommender Systems

abstract:
  Recommender systems associated with social networks often use social
explanations (e.g. "X, Y and 2 friends like this") to support the
recommendations. We present a study of the effects of these social explanations
in a music recommendation context. We start with an experiment with 237 users,
in which we show explanations with varying levels of social information and
analyze their effect on users' decisions. We distinguish between two key
decisions: the likelihood of checking out the recommended artist, and the
actual rating of the artist based on listening to several songs. We find that
while the explanations do have some influence on the likelihood, there is
little correlation between the likelihood and actual (listening) rating for the
same artist. Based on these insights, we present a generative probabilistic
model that explains the interplay between explanations and background
information on music preferences, and how that leads to a final likelihood
rating for an artist. Acknowledging the impact of explanations, we discuss a
general recommendation framework that models external informational elements in
the recommendation interface, in addition to inherent preferences of users.


title:
Merging Satellite Measurements of Rainfall Using Multi-scale Imagery
  Technique

abstract:
  Several passive microwave satellites orbit the Earth and measure rainfall.
These measurements have the advantage of almost full global coverage when
compared to surface rain gauges. However, these satellites have low temporal
revisit and missing data over some regions. Image fusion is a useful technique
to fill in the gaps of one image (one satellite measurement) using another one.
The proposed algorithm uses an iterative fusion scheme to integrate information
from two satellite measurements. The algorithm is implemented on two datasets
for 7 years of half-hourly data. The results show significant improvements in
rain detection and rain intensity in the merged measurements.


title: Electrically-protected resonant exchange qubits in triple quantum dots

abstract:
  We present a modulated microwave approach for quantum computing with qubits
comprising three spins in a triple quantum dot. This approach includes single-
and two-qubit gates that are protected against low-frequency electrical noise,
due to an operating point with a narrowband response to high frequency electric
fields. Furthermore, existing double quantum dot advances, including robust
preparation and measurement via spin-to-charge conversion, are immediately
applicable to the new qubit. Finally, the electric dipole terms implicit in the
high frequency coupling enable strong coupling with superconducting microwave
resonators, leading to more robust two-qubit gates.


title:
e-MERLIN observations at 5 GHz of the GOODS-N region: pinpointing AGN
  cores in high redshift galaxies

abstract:
  We present 5 GHz e-MERLIN observations of the GOODS-N region at sub-arcsec
resolution (0.2--0.5 arcsec). These data form part of the early commissioning
observations for the e-MERLIN interferometer and a pilot for the e-MERLIN
legacy program eMERGE. A total of 17 sources were detected with S/N>3. These
observations provide unique information on the radio source morphology at
sub-arcsec scales. For twelve of these sources, deeper 1.4 GHz MERLIN+VLA
observations at the same spatial resolution are available, allowing radio
spectral indices to be derived for ten sources on sub-arcsec angular scales.
Via analysis of the spectral indices and radio morphologies, these sources have
been identified as AGN cores in moderate-to-high redshift (1<z<4) galaxies.
These results have provided AGN (or AGN candidate) classification for six
previously unclassified sources and confirmed the AGN nature of the rest of the
sample. Ultimately the eMERGE project will image the GOODS-N region at 1.4 and
5 GHz with higher resolution (about 50 mas at 5 GHz) and down to sub-microJy
sensitivities. The unique combination of sensitivity and spatial resolution
will be exploited to study star formation and AGN activity in distant galaxies.


title:
The case for high precision in elemental abundances of stars in the era
  of large spectroscopic surveys

abstract:
  A number of large spectroscopic surveys of stars in the Milky Way are under
way or are being planned. In this context it is important to discuss the extent
to which elemental abundances can be used as discriminators between different
(known and unknown) stellar populations in the Milky Way. We aim to establish
the requirements in terms of precision in elemental abundances, as derived from
spectroscopic surveys of the Milky Way's stellar populations, in order to
detect interesting substructures in elemental abundance space. We present a
simple relation between the minimum number of stars needed to detect a given
substructure and the precision of the measurements. The results are in
agreement with recent small- and large-scale studies, with high and low
precision, respectively. Large-number statistics cannot fully compensate for
low precision in the abundance measurements and each survey should carefully
evaluate what the main science drivers are for the survey and ensure that the
chosen observational strategy will result in the precision necessary to answer
the questions posed.


title:
Spectra and ratios of identified particles in Au+Au and d+Au collisions
  at sqrt(s_NN)=200 GeV

abstract:
  The transverse momentum (p_T) spectra and ratios of identified charged
hadrons (\pi^+/-, K^+/-, p, p^bar) produced in sqrt(s_NN)=200 GeV Au+Au and
d+Au collisions are reported in five different centrality classes for each
collision species. The measurements of pions and protons are reported up to
p_T=6 GeV/c (5 GeV/c), and the measurements of kaons are reported up to p_T=4
GeV/c (3.5 GeV/c) in Au+Au (d+Au) collisions. In the intermediate p_T region,
between 2--5 GeV/c, a significant enhancement of baryon to meson ratios
compared to those measured in p+p collisions is observed. This enhancement is
present in both Au+Au and d+Au collisions, and increases as the collisions
become more central. We compare a class of peripheral Au+Au collisions with a
class of central d+Au collisions which have a comparable number of
participating nucleons and binary nucleon-nucleon collisions. The p_T dependent
particle ratios for these classes display a remarkable similarity, which is
then discussed.


title: Global Warming and Caspian Sea Level Fluctuations

abstract:
  Coastal regions have a high social, economical and environmental importance.
Due to this importance the sea level fluctuations can have many bad
consequences. In this research the correlation between the increasing trend of
temperature in coastal stations due to Global Warming and the Caspian Sea level
has been established. The Caspian Sea level data has been received from the
Jason-1 satellite. It was resulted that the monthly correlation between the
temperature and sea level is high and also positive and almost the same for all
the stations. But the yearly correlation was negative. It means that the sea
level has decreased by the increase in temperature.


title:
Representations of Rational Cherednik algebras with minimal support and
  torus knots

abstract:
  We obtain several results about representations of rational Cherednik
algebras, and discuss their applications. Our first result is the
Cohen-Macaulayness property (as modules over the polynomial ring) of Cherednik
algebra modules with minimal support. Our second result is an explicit formula
for the character of an irreducible minimal support module in type A_{n-1} for
c=m/n, and an expression of its quasispherical part (i.e., the isotypic part of
"hooks") in terms of the HOMFLY polynomial of a torus knot colored by a Young
diagram. We use this formula and the work of Calaque, Enriquez and Etingof to
give explicit formulas for the characters of the irreducible equivariant
D-modules on the nilpotent cone for SL_m. Our third result is the construction
of the Koszul-BGG complex for the rational Cherednik algebra, which generalizes
the construction of the Koszul-BGG resolution by Berest-Etingof-Ginzburg and
Gordon, and the calculation of its homology in type A. We also show in type A
that the differentials in the Koszul-BGG complex are uniquely determined by the
condition that they are nonzero homomorphisms of modules over the Cherednik
algebra. Finally, our fourth result is the symmetry theorem, which identifies
the quasispherical components in the representations with minimal support over
the rational Cherednik algebras H_{m/n}(S_n) and H_{n/m}(S_m). In fact, we show
that the simple quotients of the corresponding quasispherical subalgebras are
isomorphic as filtered algebras. This symmetry has a natural interpretation in
terms of invariants of torus knots.


title: The Resonant Exchange Qubit

abstract:
  We introduce a solid-state qubit in which exchange interactions among
confined electrons provide both the static longitudinal field and the
oscillatory transverse field, allowing rapid and full qubit control via rf
gate-voltage pulses. We demonstrate two-axis control at a detuning sweet-spot,
where leakage due to hyperfine coupling is suppressed by the large exchange
gap. A {\pi}/2-gate time of 2.5 ns and a coherence time of 19 {\mu}s, using
multi-pulse echo, are also demonstrated. Model calculations that include
effects of hyperfine noise are in excellent quantitative agreement with
experiment.


title:
Under Pressure: Star Clusters and the Neutral Hydrogen Medium of Tidal
  Tails

abstract:
  Using archival data from ATCA, WSRT, and the VLA, we have analyzed the HI
emission of 22 tidal tail regions of the Mullan et al. sample of pairwise
interacting galaxies. We have measured the column densities, line-of-sight
velocity dispersions, and kinetic energy densities on ~kpc scales. We also
constructed a tracer of the line-of-sight velocity gradient over ~10 kpc
scales. We compared the distributions of these properties between regions that
do and do not contain massive star cluster candidates (M_V < -8.5; ~10^4--10^6
M_(sun) as observed in HST WFPC2 VI data). In agreement with Maybhate et al.,
we find that a local, ~kpc-scale column density of log N_(HI) = 20.6 cm^(-2) is
frequently required for detecting clustered star formation. This HI gas also
tends to be turbulent, with line-of-sight velocity dispersions ~10--75 km/s,
implying high kinetic energy densities (>46 erg pc^(-2)). Thus, high HI
densities and pressures, partly determined by the tail dynamical age and other
interaction characteristics, are connected to large-scale cluster formation in
tidal tails overall. Lastly, we find that the high mechanical energy densities
of the gas are likely not generally due to feedback from star formation.
Rather, these properties are more likely to be a cause of star formation than a
result.


title:
No flares from Gamma-Ray Burst afterglow blast waves encountering sudden
  circumburst density change

abstract:
  Afterglows of gamma-ray bursts are observed to produce light curves with the
flux following power law evolution in time. However, recent observations reveal
bright flares at times on the order of minutes to days. One proposed
explanation for these flares is the interaction of a relativistic blast wave
with a circumburst density transition. In this paper, we model this type of
interaction computationally in one and two dimensions, using a relativistic
hydrodynamics code with adaptive mesh refinement called RAM, and analytically
in one dimension. We simulate a blast wave traveling in a stellar wind
environment that encounters a sudden change in density, followed by a
homogeneous medium, and compute the observed radiation using a synchrotron
model. We show that flares are not observable for an encounter with a sudden
density increase, such as a wind termination shock, nor for an encounter with a
sudden density decrease. Furthermore, by extending our analysis to two
dimensions, we are able to resolve the spreading, collimation, and edge effects
of the blast wave as it encounters the change in circumburst medium. In all
cases considered in this paper, we find that a flare will not be observed for
any of the density changes studied.


title: Two-Qubit Gates for Resonant Exchange Qubits

abstract:
  A new approach to single-qubit operations using exchange interactions of
single electrons in gate-defined quantum dots has recently been demonstrated:
the resonant exchange qubit. We show that two-qubit operations, specifically
the CPHASE gate, can be performed between resonant exchange qubits very
straightforwardly, using a single exchange pulse. This is in marked contrast to
the best known protocols for exchange qubits where such a gate requires many
pulses so that leakage processes arising from the exchange interaction can be
overcome. For resonant exchange qubits a simple two-qubit gate is possible
because in this mode of operation energy conservation suppresses leakage.


title: Berglund-H\"ubsch-Krawitz Mirrors via Shioda Maps

abstract:
  We give an elementary approach to proving the birationality of multiple
Berglund-H\"ubsch-Krawitz (BHK) mirrors by using Shioda maps. We do this by
creating a birational picture of the BHK correspondence in general. Although a
similar result has been obtained in recent months by Shoemaker, our proof is
new in that it sidesteps using toric geometry and drops an unnecessary
hypothesis. We give an explicit quotient of a Fermat variety to which the
mirrors are birational.


title: An Inequality Paradigm for Probabilistic Knowledge

abstract:
  We propose an inequality paradigm for probabilistic reasoning based on a
logic of upper and lower bounds on conditional probabilities. We investigate a
family of probabilistic logics, generalizing the work of Nilsson [14]. We
develop a variety of logical notions for probabilistic reasoning, including
soundness, completeness justification; and convergence: reduction of a theory
to a simpler logical class. We argue that a bound view is especially useful for
describing the semantics of probabilistic knowledge representation and for
describing intermediate states of probabilistic inference and updating. We show
that the Dempster-Shafer theory of evidence is formally identical to a special
case of our generalized probabilistic logic. Our paradigm thus incorporates
both Bayesian "rule-based" approaches and avowedly non-Bayesian "evidential"
approaches such as MYCIN and DempsterShafer. We suggest how to integrate the
two "schools", and explore some possibilities for novel synthesis of a variety
of ideas in probabilistic reasoning.


title: Probabilistic Interpretations for MYCIN's Certainty Factors

abstract:
  This paper examines the quantities used by MYCIN to reason with uncertainty,
called certainty factors. It is shown that the original definition of certainty
factors is inconsistent with the functions used in MYCIN to combine the
quantities. This inconsistency is used to argue for a redefinition of certainty
factors in terms of the intuitively appealing desiderata associated with the
combining functions. It is shown that this redefinition accommodates an
unlimited number of probabilistic interpretations. These interpretations are
shown to be monotonic transformations of the likelihood ratio p(EIH)/p(El H).
The construction of these interpretations provides insight into the assumptions
implicit in the certainty factor model. In particular, it is shown that if
uncertainty is to be propagated through an inference network in accordance with
the desiderata, evidence must be conditionally independent given the hypothesis
and its negation and the inference network must have a tree structure. It is
emphasized that assumptions implicit in the model are rarely true in practical
applications. Methods for relaxing the assumptions are suggested.