title: Jordan groups and automorphism groups of algebraic varieties

abstract:
  This is the expanded version of my talk at the workshop "Groups of
Automorphisms in Birational and Affine Geometry", October 29--November 3, 2012,
Levico Terme, Italy. The first section is focused on Jordan groups in abstract
setting, the second on that in the settings of automorphisms groups and groups
of birational self-maps of algebraic varieties. The appendix is the expanded
version of my notes on open problems posted on the site of this workshop. It
contains formulations of some open problems and the relevant comments.


title:
Orbital stability of standing waves of a class of fractional Schrodinger
  equations with a general Hartree-type integrand

abstract:
  This article is concerned with the mathematical analysis of a class of a
nonlinear fractional Schrodinger equations with a general Hartree-type
integrand. We prove existence and uniqueness of global-in-time solutions to the
associated Cauchy problem. Under suitable assumptions, we also prove the
existence of standing waves using the method of concentration-compactness by
studying the associated constrained minimization problem. Finally we show the
orbital stability of standing waves which are the minimizers of the associate
variational problem.


title: The Random Coding Bound Is Tight for the Average Linear Code or Lattice

abstract:
  In 1973, Gallager proved that the random-coding bound is exponentially tight
for the random code ensemble at all rates, even below expurgation. This result
explained that the random-coding exponent does not achieve the expurgation
exponent due to the properties of the random ensemble, irrespective of the
utilized bounding technique. It has been conjectured that this same behavior
holds true for a random ensemble of linear codes. This conjecture is proved in
this paper. Additionally, it is shown that this property extends to Poltyrev's
random-coding exponent for a random ensemble of lattices.


title:
Long-term study of backgrounds in the DRIFT-II directional dark matter
  experiment

abstract:
  Low-pressure gas Time Projection Chambers being developed for directional
dark matter searches offer a technology with strong particle identification
capability combined with the potential to produce a definitive detection of
Galactic Weakly Interacting Massive Particle (WIMP) dark matter. A source of
events able to mimic genuine WIMP-induced nuclear recoil tracks arises in such
experiments from the decay of radon gas inside the vacuum vessel. The recoils
that result from associated daughter nuclei are termed Radon Progeny Recoils
(RPRs). We present here experimental data from a long-term study using the
DRIFT-II directional dark matter experiment at the Boulby Underground
Laboratory of the RPRs, and other backgrounds that are revealed by relaxing the
normal cuts that are applied to WIMP search data. By detailed examination of
event classes in both spatial and time coordinates using 5.5 years of data, we
demonstrate the ability to determine the origin of 4 specific background
populations and describe development of new technology and mitigation
strategies to suppress them.


title: Pencils of small degree on curves on unnodal Enriques surfaces

abstract:
  We use vector-bundle techniques in order to compute $\dim W^1_d(C)$ where $C$
is general and smooth in a linear system on an unnodal Enriques surface. We
furthermore find new examples of smooth curves on Enriques surfaces with an
infinite number of $g^1_{\gon(C)}$'s.


title: Loop Quantum Cosmology and the Fine Structure Constant

abstract:
  The cosmological implications of introducing a variation to the fine
structure `constant', \alpha are examined within the context of Loop Quantum
Cosmology. The evolution of \alpha is described using the model introduced by
Bekenstein, Sandvik, Barrow and Magueijo, in which a ghost scalar field
produces the variation. The dynamics of the system are examined in flat and
closed cosmological settings. Matter consisting of the scalar field and
radiation are examined with a thermodynamically motivated coupling between the
two, which can lead to a series of bounces induced by both the negative density
effects of the ghost field and the loop effects.


title:
Projections and Idempotents in star-reducing Rings Involving the
  Moore-Penrose Inverse

abstract:
  In [Comput. Math. Appl. 59 (2010) 764-778], Baksalary and Trenkler
characterized some complex idempotent matrices of the form
$(I-PQ)^{\dag}P(I-Q)$, $(I-QP)^{\dag}(I-Q)$ and $P(P+Q-QP)^{\dag}$ in terms of
the column spaces and null spaces of $P$ and $Q$, where $P, Q\in
\mathbb{C}^{\textsf{OP}}_n = \{L\in \mathbb{C}_{n,n}\ |\ L^2 = L = L^*\}$. We
generalize these results from $\mathbb{C}_{n,n}$ to any *-reducing rings.


title: Computing the bound of an Ore polynomial. Applications to factorization

abstract:
  We develop a fast algorithm for computing the bound of an Ore polynomial over
a skew field, under mild conditions. As an application, we state a criterion
for deciding whether a bounded Ore polynomial is irreducible, and we discuss a
factorization algorithm. The asymptotic time complexity in the degree of the
given Ore polynomial is studied. In the class of Ore polynomials over a finite
field, our algorithm is an alternative to Giesbretch's one that reduces the
complexity in the degree of the polynomial.


title:
K$^0_{\rm S}$ and $\rm \Lambda$ production in Pb-Pb collisions at
  $\sqrt{s_{\rm NN}}$ = 2.76 TeV

abstract:
  The ALICE measurement of K$^0_{\rm S}$ and $\rm\Lambda$ production at
mid-rapidity in Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 2.76$ TeV is
presented. The transverse momentum ($p_{\rm T}$) spectra are shown for several
collision centrality intervals and in the $p_{\rm T}$ range from 0.4 GeV/$c$
(0.6 GeV/$c$ for $\rm\Lambda$) to 12 GeV/$c$. The $p_{\rm T}$ dependence of the
$\rm \Lambda$/K$^0_{\rm S}$ ratios exhibits maxima in the vicinity of 3
GeV/$c$, and the positions of the maxima shift towards higher $p_{\rm T}$ with
increasing collision centrality. The magnitude of these maxima increases by
almost a factor of three between most peripheral and most central Pb-Pb
collisions. This baryon excess at intermediate $p_{\rm T}$ is not observed in
pp interactions at sqrt(s) = 0.9 TeV and at sqrt(s) = 7 TeV. Qualitatively, the
baryon enhancement in heavy-ion collisions is expected from radial flow.
However, the measured $p_{\rm T}$ spectra above 2 GeV/$c$ progressively
decouple from hydrodynamical-model calculations. For higher values of $p_{\rm
T}$, models that incorporate the influence of the medium on the fragmentation
and hadronization processes describe qualitatively the $p_{\rm T}$ dependence
of the $\rm\Lambda$/K$^0_{\rm S}$ ratio.


title:
SOV approach for integrable quantum models associated to general
  representations on spin-1/2 chains of the 8-vertex reflection algebra

abstract:
  The analysis of the transfer matrices associated to the most general
representations of the 8-vertex reflection algebra on spin-1/2 chains is here
implemented by introducing a quantum separation of variables (SOV) method which
generalizes to these integrable quantum models the method first introduced by
Sklyanin. More in detail, for the representations reproducing in their
homogeneous limits the open XYZ spin-1/2 quantum chains with the most general
integrable boundary conditions, we explicitly construct representations of the
8-vertex reflection algebras for which the transfer matrix spectral problem is
separated. Then, in these SOV representations we get the complete
characterization of the transfer matrix spectrum (eigenvalues and eigenstates)
and its non-degeneracy. Moreover, we present the first fundamental step toward
the characterization of the dynamics of these models by deriving determinant
formulae for the matrix elements of the identity on separated states, which
apply in particular to transfer matrix eigenstates. The comparison of our
analysis for the 8-vertex reflection algebra with that of [1, 2] for the
6-vertex one leads to the interesting remark that a profound similarity in both
the characterization of the spectral problems and of the scalar products exists
for these two different realizations of the reflection algebra once they are
described by SOV method. As it will be shown in a future publication, this
remarkable similarity will be at the basis of the simultaneous determination of
form factors of local operators of integrable quantum models associated to
general reflection algebra representations of both 8-vertex and 6-vertex type.


title:
Quantum entanglement for two electrons in the excited states of
  helium-like systems

abstract:
  The quantum entanglement for the two electrons in the excited states of the
helium-like atom/ions is investigated using the two-electron wave functions
constructed by the B-spline basis. As a measure of the spatial
(electron-electron orbital) entanglement, the von Neumann entropy and linear
entropy of the reduced density matrix are calculated for the 1s2s 1,3S excited
states for systems with some selected Z values from Z=2 to Z=100. Results for
the helium atom are compared with other available calculations. We have also
investigated the entropies for these excited states when the nucleus charge is
reduced from Z=2 to Z=1. At such a critical charge, all the singly-excited
states of this system become unbound, and the linear entropies and the von
Neumann entropies for the excited states are approaching 1/2 and 1,
respectively, the limits for the entropies when one electron is bound to the
nucleus, and the other being free.


title: An Enhanced Spectroscopic Census of the Orion Nebula Cluster

abstract:
  We report new spectral types or spectral classification constraints for over
600 stars in the Orion Nebula Cluster (ONC) based on medium resolution R~
1500-2000 red optical spectra acquired using the Palomar 200" and Kitt Peak
3.5m telescopes. Spectral types were initially estimated for F, G, and early K
stars from atomic line indices while for late K and M stars, constituting the
majority of our sample, indices involving TiO and VO bands were used. To ensure
proper classification, particularly for reddened, veiled, or
nebula-contaminated stars, all spectra were then visually examined for type
verification or refinement. We provide an updated spectral type table that
supersedes Hillenbrand (1997), increasing the percentage of optically visible
ONC stars with spectral type information from 68% to 90%. However, for many
objects, repeated observations have failed to yield spectral types primarily
due to the challenges of adequate sky subtraction against a bright and
spatially variable nebular background. The scatter between our new and our
previously determined spectral types is approximately 2 spectral sub-classes.
We also compare our grating spectroscopy results with classification based on
narrow-band TiO filter photometry from Da Rio et al. (2012, finding similar
scatter. While the challenges of working in the ONC may explain much of the
spread, we highlight several stars showing significant and unexplained bona
fide spectral variations in observations taken several years apart; these and
similar cases could be due to a combination of accretion and extinction
changes. Finally, nearly 20% of ONC stars exhibit obvious Ca II triplet
emission indicative of strong accretion.


title:
A New Optimization Approach Based on Rotational Mutation and Crossover
  Operator

abstract:
  Evaluating a global optimal point in many global optimization problems in
large space is required to more calculations. In this paper, there is presented
a new approach for the continuous functions optimization with rotational
mutation and crossover operator. This proposed method (RMC) starts from the
point which has best fitness value by elitism mechanism and after that
rotational mutation and crossover operator are used to reach optimal point. RMC
method is implemented by GA (Briefly RMCGA) and is compared with other
wellknown algorithms such as: DE, PGA, Grefensstette and Eshelman[15,16] and
numerical and simulating results show that RMCGA achieve global optimal point
with more decision by smaller generations.


title: Non-minimal Gravitational Coupling of Phantom and Big Rip Singularity

abstract:
  We consider a non-minimal coupling of a perfect fluid matter system with
geometry, which the coupling function is taken to be an arbitrary function of
the Ricci scalar. Due to such a coupling, the matter stress tensor is no longer
conserved and there is an energy transfer between the two components. By
solving the conservation equation and applying the second law of
thermodynamics, we show that direction of the energy transfer depends on the
equation of state of the matter fluid. In particular, a phantom fluid should
loose energy with expansion of the universe. This energy reduction can avoid
the universe to end with a cosmic doomsday.


title:
Electromagnetic two-point functions and Casimir densities for a
  conducting plate in de Sitter spacetime

abstract:
  We evaluate the two-point function for the electromagnetic field tensor in
$(D+1)$-dimensional de Sitter spacetime assuming that the field is prepared in
Bunch-Davies vacuum state. This two-point function is used for the
investigation of the vacuum expectation values (VEVs) of the field squared and
the energy-momentum tensor in the presence of a conducting plate. The VEVs are
decomposed into the boundary-free and plate-induced parts. For the latter,
closed form analytical expressions are given in terms of the hypergeometric
function. For $3\leqslant D\leqslant 8$ the plate-induced part in the VEV of
the electric field squared is positive everywhere, whereas for $D\geqslant 9$
it is positive near the plate and negative at large distances. The VEV of the
energy-momentum tensor, in addition to the diagonal components, contains an
off-diagonal component which corresponds to the energy flux along the direction
normal to the plate. Simple asymptotic expressions are provided at small and
large distances from the plate compared with the de Sitter curvature scale. For
$D\geqslant 4$, all the diagonal components of the plate-induced vacuum
energy-momentum tensor are negative and the energy flux is directed from the
plate.


title:
Some symmetry results for entire solutions of an elliptic system arising
  in phase separation

abstract:
  We study the one dimensional symmetry of entire solutions to an elliptic
system arising in phase separation for Bose-Einstein condensates with multiple
states. We prove that any monotone solution, with arbitrary algebraic growth at
infinity, must be one dimensional in the case of two spatial variables. We also
prove the one dimensional symmetry for half-monotone solutions, i.e., for
solutions having only one monotone component.


title: Dual-readout Calorimetry

abstract:
  The RD52 Project at CERN is a pure instrumentation experiment whose goal is
to understand the fundamental limitations to hadronic energy resolution, and
other aspects of energy measurement, in high energy calorimeters. We have found
that dual-readout calorimetry provides heretofore unprecedented information
event-by-event for energy resolution, linearity of response, ease and
robustness of calibration, fidelity of data, and particle identification,
including energy lost to binding energy in nuclear break-up. We believe that
hadronic energy resolutions of {\sigma}/E $\approx$ 1 - 2% are within reach for
dual-readout calorimeters, enabling for the first time comparable measurement
preci- sions on electrons, photons, muons, and quarks (jets). We briefly
describe our current progress and near-term future plans. Complete information
on all aspects of our work is available at the RD52 website
http://highenergy.phys.ttu.edu/dream/.


title: Superintegrability in two dimensions and the Racah-Wilson algebra

abstract:
  The analysis of the most general second-order superintegrable system in two
dimensions: the generic 3-parameter model on the 2-sphere, is cast in the
framework of the Racah problem for the su(1,1) algebra. The Hamiltonian of the
3-parameter system and the generators of its quadratic symmetry algebra are
seen to correspond to the total and intermediate Casimir operators of the
combination of three su(1,1) algebras, respectively. The construction makes
explicit the isomorphism between the Racah-Wilson algebra, which is the
fundamental algebraic structure behind the Racah problem for su(1,1), and the
invariance algebra of the generic 3-parameter system. It also provides an
explanation for the occurrence of the Racah polynomials as overlap coefficients
in this context. The irreducible representations of the Racah-Wilson algebra
are reviewed as well as their connection with the Askey scheme of classical
orthogonal polynomials.


title: On the Pricing of Storable Commodities

abstract:
  This paper introduces an information-based model for the pricing of storable
commodities such as crude oil and natural gas. The model uses the concept of
market information about future supply and demand as a basis for valuation.
Physical ownership of a commodity is taken to provide a stream of convenience
dividends equivalent to a continuous cash flow. The market filtration is
assumed to be generated jointly by (i) current and past levels of the dividend
rate, and (ii) partial information concerning the future of the dividend flow.
The price of a commodity is the expectation under a suitable pricing measure of
the totality of the discounted risk-adjusted future convenience dividend,
conditional on the information provided by the market filtration. In the
situation where the dividend rate is modelled by an Ornstein-Uhlenbeck process,
the prices of options on commodities can be derived in closed form. The
approach that we present can be applied to other assets that yield potentially
negative effective cash flows, such as real estate, factories, refineries,
mines, and power generating plants.


title: Comparative Statics On The Allocation Of Spectrum

abstract:
  Allocation of spectrum is an important policy issue and decisions taken have
ramifications for future growth of wireless communications and achieving
universal connectivity. In this paper, on a common footing we compare the
social welfare obtained from the allocation of new spectrum under different
alternatives: to licensed providers in monopolistic, oligopolistic and
perfectly competitive settings, and for unlicensed access. For this purpose we
use mathematical models of competition in congestible resources. Initially we
assume that any new bandwidth is available for free, but we also generalize our
results to include investment decisions when prices are charged for bandwidth
acquisition.


title: Fourier-Dedekind Sums and an Extension of Rademacher Reciprocity

abstract:
  Fourier-Dedekind sums are a generalization of Dedekind sums - important
number-theoretical objects that arise in many areas of mathematics, including
lattice point enumeration, signature defects of manifolds and pseudo random
number generators. A remarkable feature of Fourier-Dedekind sums is that they
satisfy a reciprocity law called Rademacher reciprocity. In this paper, we
study several aspects of Fourier-Dedekind sums: properties of general
Fourier-Dedekind sums, extensions of the reciprocity law, average behavior of
Fourier-Dedekind sums, and finally, extrema of 2-dimensional Fourier-Dedekind
sums.
  On properties of general Fourier-Dedekind sums we show that a general
Fourier-Dedekind sum is simultaneously a convolution of simpler
Fourier-Dedekind sums, and a linear combination of these with integer
coefficients. We show that Fourier-Dedekind sums can be extended naturally to a
group under convolution. We introduce "Reduced Fourier-Dedekind sums", which
encapsulate the complexity of a Fourier-Dedekind sum, describe these in terms
of generating functions, and give a geometric interpretation.
  Next, by finding interrelations among Fourier-Dedekind sums, we extend the
range on which Rademacher reciprocity Theorem holds.
  We go on to study the average behavior of Fourier-Dedekind sums, showing that
the average behavior of a Fourier-Dedekind sum is described concisely by a
lower-dimensional, simpler Fourier-Dedekind sum.
  Finally, we focus our study on 2-dimensional Fourier-Dedekind sums. We find
tight upper and lower bounds on these for a fixed $t$, estimates on the argmax
and argmin, and bounds on the sum of their "reciprocals".


title:
Multi-strange baryon production at mid-rapidity in Pb-Pb collisions at
  $\sqrt{s_{\rm NN}}$ = 2.76 TeV

abstract:
  The production of ${\rm\Xi}^-$ and ${\rm\Omega}^-$ baryons and their
anti-particles in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV has been
measured using the ALICE detector. The transverse momentum spectra at
mid-rapidity ($|y| < 0.5$) for charged $\rm\Xi$ and $\rm\Omega$ hyperons have
been studied in the range $0.6 < p_{\rm T} < 8.0$ GeV/$c$ and $1.2 < p_{\rm T}
< 7.0$ GeV/$c$, respectively, and in several centrality intervals (from the
most central 0-10% to the most peripheral 60-80% collisions). These spectra
have been compared with the predictions of recent hydrodynamic models. In
particular, the Krak${\'o}$w and EPOS models give a satisfactory description of
the data, with the latter covering a wider $p_{\rm T}$ range. Mid-rapidity
yields, integrated over $p_{\rm T}$, have been determined. The hyperon-to-pion
ratios are similar to those at RHIC: they rise smoothly with centrality up to
$\langle N_{\rm part}\rangle$~150 and saturate thereafter. The enhancements
(yields per participant nucleon relative to pp collisions) increase both with
the strangeness content of the baryon and with centrality, but are less
pronounced than at lower energies.


title: Work and Quantum Phase Transitions: Is there Quantum Latency?

abstract:
  We study the physics of quantum phase transitions from the perspective of
non-equilibrium thermodynamics. For first order quantum phase transitions, we
find that the average work done per quench in crossing the critical point is
discontinuous. This leads us to introduce the quantum latent work in analogy
with the classical latent heat of first order classical phase transitions. For
second order quantum phase transitions the irreversible work is closely related
to the fidelity susceptibility for weak sudden quenches of the system
Hamiltonian. We demonstrate our ideas with numerical simulations of first,
second, and infinite order phase transitions in various spin chain models.


title: Influence of excitation frequency on Raman modes of In1-xGaxN thin films

abstract:
  Low energy optical modes of MBE-grown In1-xGaxN thin films with different
values of x are investigated using Raman spectroscopy. We also studied the
influence of Raman excitation frequency using red and green lasers on
scattering intensity of various Raman modes. For those In1-xGaxN alloys whose
bandgap energy is close to the red laser, a huge enhancement in the intensities
of A1(LO) mode and its 2A1(LO) replica is observed when excited with red laser
as compared to the green laser excitation. We found that the energies of
longitudinal optical modes (A1 (LO) and 2A1 (LO)) vary nonlinearly unlike the
E2 mode with increasing Ga atomic fraction. A Raman mode ~ 540 cm-1 was
observed in all In1-xGaxN films with low energy red laser excitation but was
absent with green laser excitation. We attribute this mode to A1(TO) mode of
the underneath GaN buffer layer.


title:
Quantum group approach to steady states of boundary-driven open quantum
  systems

abstract:
  We present a systematic approach for constructing steady state density
operators of Markovian dissipative evolution for open quantum chain models with
integrable bulk interaction and boundary incoherent driving. The construction
is based on fundamental solutions of the quantum Yang-Baxter equation
pertaining to quantum algebra symmetries and their quantizations
(q-deformations). In particular, we facilitate a matrix-product state
description, by resorting to generic spin-s infinite-dimensional solutions
associated with non-compact spins, serving as ancillary degrees of freedom.
After formally deriving already known solutions for the anisotropic spin-1/2
Heisenberg chain from first symmetry principles, we obtain a class of solutions
belonging to interacting quantum gases with SU(N)-symmetric Hamiltonians, using
a restricted set of incoherent boundary jump processes, and point out how new
non-trivial generalizations emerge from twists of quantum group structures.
Finally, we discuss possibilities of analytic calculation of observables by
employing algebraic properties of associated auxiliary vertex operators.

categories: quant-ph cond-mat.stat-mech math-ph math.MP


title: Linear-Time Recognition of Probe Interval Graphs

abstract:
  The interval graph for a set of intervals on a line consists of one vertex
for each interval, and an edge for each intersecting pair of intervals. A probe
interval graph is a variant that is motivated by an application to genomics,
where the intervals are partitioned into two sets: probes and non-probes. The
graph has an edge between two vertices if they intersect and at least one of
them is a probe. We give a linear-time algorithm for determining whether a
given graph and partition of vertices into probes and non-probes is a probe
interval graph. If it is, we give a layout of intervals that proves this. We
can also determine whether the layout of the intervals is uniquely constrained
within the same time bound. As part of the algorithm, we solve the
consecutive-ones probe matrix problem in linear time, develop algorithms for
operating on PQ trees, and give results that relate PQ trees for different
submatrices of a consecutive-ones matrix.


title:
Emission of forward neutrons by 158A GeV indium nuclei in collisions
  with Al, Cu, Sn and Pb

abstract:
  The cross sections of forward emission of one, two and three neutrons by 158A
GeV 115In nuclei in collisions with Al, Cu, Sn and Pb targets are reported. The
measurements were performed in the framework of the ALICE-LUMI experiment at
the SPS facility at CERN. Various corrections accounting for the absorption of
beam nuclei and produced neutrons in target material and surrounding air were
introduced. The corrected cross section data are compared with the predictions
of the RELDIS model for electromagnetic fragmentation of 115In in
ultraperipheral collisions, as well as with the results of the
abrasion-ablation model for neutron emission in hadronic interactions. The
measured neutron emission cross sections well agree with the RELDIS results,
with the exception of In-Al collisions where the measured cross sections are
larger compared to RELDIS. This is attributed to a relatively large
contribution of hadronic fragmentation of In on Al target with respect to
electromagnetic fragmentation, on the contrary to similar measurements
performed earlier with 30A GeV 208Pb colliding with Al.


title:
Insufficiency of Linear-Feedback Schemes In Gaussian Broadcast Channels
  with Common Message

abstract:
  We consider the $K\geq 2$-user memoryless Gaussian broadcast channel (BC)
with feedback and common message only. We show that linear-feedback schemes
with a message point, in the spirit of Schalkwijk & Kailath's scheme for
point-to-point channels or Ozarow & Leung's scheme for BCs with private
messages, are strictly suboptimal for this setup. Even with perfect feedback,
the largest rate achieved by these schemes is strictly smaller than capacity
$C$ (which is the same with and without feedback). In the extreme case where
the number of receivers $K\to \infty$, the largest rate achieved by
linear-feedback schemes with a message point tends to 0.
  To contrast this negative result, we describe a scheme for
\emph{rate-limited} feedback that uses the feedback in an intermittent way,
i.e., the receivers send feedback signals only in few channel uses. This scheme
achieves all rates $R$ up to capacity $C$ with an $L$-th order exponential
decay of the probability of error if the feedback rate $R_{\textnormal{fb}}$ is
at least $(L-1)R$ for some positive integer $L$.


title:
Exact closed equation for reduced equilibrium distribution functions of
  the many-particle system

abstract:
  An exact closed equation for s - particle equilibrium distribution function
(s<N) of the system of N>>1 interacting particles is obtained. This
integra-differential {\beta} - convolution equation ({\beta}=1/k_{B}T) follows
from the Bloch equation for the canonical distribution function by applying the
projection operator integrating off the coordinates of N-s irrelevant
particles. The method of expansion of the obtained equation kernel in the
particle density n is suggested. The solution to this equation in the linear in
n approximation for the kernel is found.


title: Regularized Discrete Optimal Transport

abstract:
  This article introduces a generalization of the discrete optimal transport,
with applications to color image manipulations. This new formulation includes a
relaxation of the mass conservation constraint and a regularization term. These
two features are crucial for image processing tasks, which necessitate to take
into account families of multimodal histograms, with large mass variation
across modes.
  The corresponding relaxed and regularized transportation problem is the
solution of a convex optimization problem. Depending on the regularization
used, this minimization can be solved using standard linear programming methods
or first order proximal splitting schemes.
  The resulting transportation plan can be used as a color transfer map, which
is robust to mass variation across images color palettes. Furthermore, the
regularization of the transport plan helps to remove colorization artifacts due
to noise amplification.
  We also extend this framework to the computation of barycenters of
distributions. The barycenter is the solution of an optimization problem, which
is separately convex with respect to the barycenter and the transportation
plans, but not jointly convex. A block coordinate descent scheme converges to a
stationary point of the energy. We show that the resulting algorithm can be
used for color normalization across several images. The relaxed and regularized
barycenter defines a common color palette for those images. Applying color
transfer toward this average palette performs a color normalization of the
input images.


title:
Any Positive Feedback Rate Increases the Capacity of Strictly Less-Noisy
  Broadcast Channels

abstract:
  We propose two coding schemes for discrete memoryless broadcast channels
(DMBCs) with rate-limited feedback from only one receiver. For any positive
feedback rate and for the class of strictly less-noisy DMBCs, our schemes
strictly improve over the no-feedback capacity region.


title: Production of hypernuclei in peripheral relativistic ion collisions

abstract:
  Within a dynamical and statistical approach we study the main regularities in
production of hypernuclei coming from projectile and target residues in
relativistic ion collisions. We demonstrate that yields of hypernuclei increase
considerably above the energy threshold for Lambda hyperons, and there is a
saturation for yields of single hypernuclei with increasing the beam energy up
to few TeV. Production of specific hypernuclei depend very much on the isotopic
composition of the projectile, and this gives a chance to obtain exotic
hypernuclei that may be difficult to reach in traditional hypernuclear
experiments. Possibilities for the detection of such hypernuclei with planned
and available relativistic ion facilities are discussed.


title: An Equivariant Version of Hatcher's G/O Construction

abstract:
  We explicitly construct generators of the rational homotopy groups of the
space of stable h-cobordisms of the classifying space of a cyclic group of
order n by generalizing a construction of Hatcher. This result will be used in
a separate paper by the third author to classify axiomatic higher twisted
torsion invariants.


title: Semi-negativity of Hodge bundles associated to Du Bois families

abstract:
  In this note we show that the sheaf $R^1 f_* \mathcal{O}_X$ is an anti-nef
vector bundle (i.e., its dual is nef), where $f : X \to Y$ is a family of Du
Bois schemes of pure dimension.


title: Long Gamma Ray Bursts Trace The Star Formation History

abstract:
  We show that if the broad-line supernova explosions of type Ic (SNeIc)
produce the bulk of the observed long duration gamma ray bursts (LGRBs), which
include the high luminosity GRBs, low luminosity GRBs and X-ray flashes (XRFs),
and if LGRBs have the geometry assumed in the cannonball (CB) model of LGRBs,
then their rate measured by Swift and their redshift distribution are
consistent with the star formation rate (SFR) over the entire range of
redshifts where the SFR has been measured with sufficient accuracy.


title:
Room-Temperature Electronically-Controlled Ferromagnetism at the
  LaAlO3/SrTiO3 Interface

abstract:
  Reports of emergent conductivity, superconductivity, and magnetism at oxide
interfaces have helped to fuel intense interest in their rich physics and
technological potential. Here we employ magnetic force microscopy to search for
room-temperature magnetism in the well-studied LaAlO3/SrTiO3 system. Using
electrical top gating to deplete electrons from the oxide interface, we
directly observe an in-plane ferromagnetic phase with sharply defined domain
walls. Itinerant electrons, introduced by a top gate, align
antiferromagnetically with the magnetization, at first screening and then
destabilizing it as the conductive state is reached. Subsequent depletion of
electrons results in a new, uncorrelated magnetic pattern. This newfound
control over emergent magnetism at the interface between two non-magnetic
oxides portends a number of important technological applications.


title: Mixtures of Common Skew-t Factor Analyzers

abstract:
  A mixture of common skew-t factor analyzers model is introduced for
model-based clustering of high-dimensional data. By assuming common component
factor loadings, this model allows clustering to be performed in the presence
of a large number of mixture components or when the number of dimensions is too
large to be well-modelled by the mixtures of factor analyzers model or a
variant thereof. Furthermore, assuming that the component densities follow a
skew-t distribution allows robust clustering of skewed data. The alternating
expectation-conditional maximization algorithm is employed for parameter
estimation. We demonstrate excellent clustering performance when our model is
applied to real and simulated data.This paper marks the first time that skewed
common factors have been used.


title: Scattering of singular beams by subwavelength objects

abstract:
  In recent years, there has been a mounting interest in better methods of
measuring nanoscale objects, especially in fields such as nanotechnology,
biomedicine, cleantech, and microelectronics. Conventional methods have proved
insufficient, due to the classical diffraction limit or slow and complicated
measuring procedures. The purpose of this paper is to explore the special
characteristics of singular beams with respect to the investigation of
subwavelength objects. Singular beams are light beams that contain one or more
singularities in their physical parameters, such as phase or polarization. We
focus on the three-dimensional interaction between electromagnetic waves and
subwavelength objects to extract information about the object from the
scattered light patterns.


title: Towards a common analysis framework for gamma-ray astronomy

abstract:
  Thanks to the success of current gamma-ray telescopes (Fermi, H.E.S.S.,
MAGIC, VERITAS), and in view of the prospects of planned observatories such as
the Cherenkov Telescope Array (CTA) or the High-Altitude Water Cherenkov
Observatory (HAWC), gamma-ray astronomy is becoming an integral part of modern
astrophysical research. Analysis today relies on a large diversity of tools and
software frameworks that were specifically and independently developed for each
instrument. With the aim of unifying the analysis of gamma-ray data, we are
currently developing GammaLib (http://sourceforge.net/projects/gammalib), a C++
library interfaced to Python that provides a framework for an instrument
independent analysis of gamma-ray data. On top of GammaLib we have created
ctools (http://cta.irap.omp.eu/ctools), a set of analysis executables that is
being developed as one of the prototypes for the CTA high-level science
analysis framework, but which is equally suited for the analysis of gamma-ray
data from the existing Fermi-LAT telescope and current Cherenkov telescope
arrays. In particular, ctools and GammaLib provide the novel opportunity of a
simultaneous multi-instrument analysis. We present the status of the software
development, and illustrate its capabilities with a spectral analysis of the
Crab nebula emission over seven decades in energy (1 MeV to 10 TeV) using
multi-instrument (COMPTEL, Fermi-LAT, H.E.S.S.) gamma-ray observations as well
as a simulation of a CTA observation of the supernova remnant RX J1713.7-3946.


title:
On the Linear Convergence of the ADMM in Decentralized Consensus
  Optimization

abstract:
  In decentralized consensus optimization, a connected network of agents
collaboratively minimize the sum of their local objective functions over a
common decision variable, where their information exchange is restricted
between the neighbors. To this end, one can first obtain a problem
reformulation and then apply the alternating direction method of multipliers
(ADMM). The method applies iterative computation at the individual agents and
information exchange between the neighbors. This approach has been observed to
converge quickly and deemed powerful. This paper establishes its linear
convergence rate for decentralized consensus optimization problem with strongly
convex local objective functions. The theoretical convergence rate is
explicitly given in terms of the network topology, the properties of local
objective functions, and the algorithm parameter. This result is not only a
performance guarantee but also a guideline toward accelerating the ADMM
convergence.


title:
A Mini X-Ray Survey of Sub-DLAs; Searching for AGNs Formed in
  Protogalaxies

abstract:
  A significant fraction of the sub-damped Lyman-alpha (sub-DLA) absorption
systems in quasar spectra appear to be metal-rich, many with even super-solar
element abundances. This raises the question whether some sub-DLAs may harbor
active galactic nuclei (AGN) since supersolar metallicities are observed in
AGN. Here we investigate this question based on a mini-survey of 21 quasars
known to contain sub-DLAs in their spectra. The X-ray observations were
performed with the Chandra X-ray Observatory. In cases of no detection we
estimated upper limits of the X-ray luminosities of possible AGNs at the
redshifts of the sub-DLAs. In six cases we find possible X-ray emission within
~ 1 arcsec of the background quasar consistent with the presence of a nearby
X-ray source. If these nearby X-ray sources are at the redshifts of the
sub-DLAs, their estimated 0.2-10 keV luminosities range between 0.8 x
10^{44}h^{-2} and 4.2 x 10^{44}h^{-2} erg s^{-1}, thus ruling out a normal
late-type galaxy origin, and suggesting that the emission originates in a
galactic nucleus near the center of a protogalaxy. The projected distances of
these possible nearby X-ray sources from the background quasars lie in the
range of 3-7 h^{-1} kpc, consistent with our hypothesis that they represent
AGNs centered on the sub-DLAs. Deeper follow-up X-ray and optical observations
are required to confirm the marginal detections of X-rays from these sub-DLA
galaxies.


title:
Social interactions dominate speed control in driving natural flocks
  toward criticality

abstract:
  Flocks of birds exhibit a remarkable degree of coordination and collective
response. It is not just that thousands of individuals fly, on average, in the
same direction and at the same speed, but that even the fluctuations around the
mean velocity are correlated over long distances. Quantitative measurements on
flocks of starlings, in particular, show that these fluctuations are
scale-free, with effective correlation lengths proportional to the linear size
of the flock. Here we construct models for the joint distribution of velocities
in the flock that reproduce the observed local correlations between individuals
and their neighbors, as well as the variance of flight speeds across
individuals, but otherwise have as little structure as possible. These
minimally structured, or maximum entropy models provide quantitative,
parameter-free predictions for the spread of correlations throughout the flock,
and these are in excellent agreement with the data. These models are
mathematically equivalent to statistical physics models for ordering in
magnets, and the correct prediction of scale-free correlations arises because
the parameters - completely determined by the data - are in the critical
regime. In biological terms, criticality allows the flock to achieve maximal
correlation across long distances with limited speed fluctuations.


title: Simple examples of affine manifolds with infinitely many exotic models

abstract:
  We give a simple general method of construction of affine varieties with
infinitely many exotic models. In particular we show that for every d>1 there
exists a Stein manifold of dimension d which has uncountably many different
structures of affine variety.


title:
RNA/peptide binding driven by electrostatics -- Insight from
  bi-directional pulling simulations

abstract:
  RNA/protein interactions play crucial roles in controlling gene expression.
They are becoming important targets for pharmaceutical applications. Due to RNA
flexibility and to the strength of electrostatic interactions, standard docking
methods are insufficient. We here present a computational method which allows
studying the binding of RNA molecules and charged peptides with atomistic,
explicit-solvent molecular dynamics. In our method, a suitable estimate of the
electrostatic interaction is used as an order parameter (collective variable)
which is then accelerated using bi-directional pulling simulations. Since the
electrostatic interaction is only used to enhance the sampling, the
approximations used to compute it do not affect the final accuracy. The method
is employed to characterize the binding of TAR RNA from HIV-1 and a small
cyclic peptide. Our simulation protocol allows blindly predicting the binding
pocket and pose as well as the binding affinity. The method is general and
could be applied to study other electrostatics-driven binding events.

categories: q-bio.BM cond-mat.soft physics.bio-ph physics.chem-ph


title:
Topological order in a correlated three-dimensional topological
  insulator

abstract:
  Motivated by experimental progress in the growth of heavy transition metal
oxides, we theoretically study a class of lattice models of interacting
fermions with strong spin-orbit coupling. Focusing on interactions of
intermediate strength, we derive a low-energy effective field theory for a
fully gapped, topologically ordered, fractionalized state with an eight-fold
ground-state degeneracy. This state is a fermionic symmetry-enriched
topological phase with particle-number conservation and time-reversal symmetry.
The topological terms in the effective field theory describe a quantized
magnetoelectric response and nontrivial mutual braiding statistics of dynamical
extended vortex loops with emergent fermions in the bulk. We explicitly compute
the expected mutual statistics in a specific model on the pyrochlore lattice
within a slave-particle mean-field theory. We argue that our model also
provides a possible condensed-matter realization of oblique confinement.


title:
Many-body nodal hypersurface and domain averages for correlated wave
  functions

abstract:
  We outline the basic notions of nodal hypersurface and domain averages for
antisymmetric wave functions. We illustrate their properties and analyze the
results for a few electron explicitly solvable cases and discuss possible
further developments.

categories: quant-ph cond-mat.other physics.atom-ph physics.chem-ph


title: Partial positivity: geometry and cohomology of q-ample line bundles

abstract:
  We give an overview of partial positivity conditions for line bundles, mostly
from a cohomological point of view. Although the current work is to a large
extent of expository nature, we present some minor improvements over the
existing literature and a new result: a Kodaira-type vanishing theorem for
effective q-ample Du Bois divisors and log canonical pairs.


title:
N-tupling the capacity of each polarization state in radio links by
  using electromagnetic vorticity

abstract:
  The congestion of the radio frequency bands imposes serious limitations on
the capacity and capability of modern wireless information infrastructures. One
approach to enable frequency re-use is to exploit other physical conserved
quantities of the electromagnetic fields, such as the orbital angular momentum
(OAM) in addition to linear momentum, which is exploited in present-day
telecommunications. Whereas in the optical regime the increase of channel
capacity by using OAM states was demonstrated recently, the receiving antennas
in commercial radio links have a much smaller extent than the transmitted beam,
making the signal reception and characterization of the OAM state demanding.
Moreover, radio data transmission with more than two channels per polarization
state at the same frequency for radio links is known to be notoriously
difficult to realize even with multiport techniques, long antenna baselines and
digital post-processing. Here we report results from an outdoor, proof of
concept experiment where the physical properties of OAM states were used to
transfer information, using far-field multiplexing/demultiplexing of three
coexisting collinear, vertically polarized and mutually independent OAM radio
beams, opening new perspectives in wireless telecommunications.


title:
Asymptotic theory of microstructured surfaces: An asymptotic theory for
  waves guided by diffraction gratings or along microstructured surfaces

abstract:
  An effective surface equation, that encapsulates the detail of a
microstructure, is developed to model microstructured surfaces. The equations
deduced accurately reproduce a key feature of surface wave phenomena, created
by periodic geometry, that are commonly called Rayleigh-Bloch waves, but which
also go under other names such as Spoof Surface Plasmon Polaritons in
photonics. Several illustrative examples are considered and it is shown that
the theory extends to similar waves that propagate along gratings. Line source
excitation is considered and an implicit long-scale wavelength is identified
and compared to full numerical simulations. We also investigate non-periodic
situations where a long-scale geometric variation in the structure is
introduced and show that localised defect states emerge which the asymptotic
theory explains.


title:
Fabrication-Adaptive Optimization, with an Application to Photonic
  Crystal Design

abstract:
  It is often the case that the computed optimal solution of an optimization
problem cannot be implemented directly, irrespective of data accuracy, due to
either (i) technological limitations (such as physical tolerances of machines
or processes), (ii) the deliberate simplification of a model to keep it
tractable (by ignoring certain types of constraints that pose computational
difficulties), and/or (iii) human factors (getting people to "do" the optimal
solution). Motivated by this observation, we present a modeling paradigm called
"fabrication-adaptive optimization" for treating issues of
implementation/fabrication. We develop computationally-focused theory and
algorithms, and we present computational results for incorporating
considerations of implementation/fabrication into constrained optimization
problems that arise in photonic crystal design. The fabrication-adaptive
optimization framework stems from the robust regularization of a function. When
the feasible region is not a normed space (as typically encountered in
application settings), the fabrication-adaptive optimization framework
typically yields a non-convex optimization problem. (In the special case where
the feasible region is a finite-dimensional normed space, we show that
fabrication-adaptive optimization can be re-cast as an instance of modern
robust optimization.) We study a variety of problems with special structures on
functions, feasible regions, and norms, for which computation is tractable, and
develop an algorithmic scheme for solving these problems in spite of the
challenges of non-convexity. We apply our methodology to compute
fabrication-adaptive designs of two-dimensional photonic crystals with a
variety of prescribed features.


title: Vector bileptons and the decays $h\rightarrow \gamma\gamma,Z\gamma$

abstract:
  Takeing into account of the constraints on the relevant parameters from the
muon anomalous magnetic moment, we consider the contributions of the vector
bileptons $V^{\pm}$ and $U^{\pm\pm}$ predicted by the reduced minimal 331 model
to the Higgs decay channels $h \rightarrow \gamma \gamma$ and $Z\gamma$. Our
numerical results show that the vector bileptons can enhance the partial width
$\Gamma(h\rightarrow \gamma\gamma)$, while reduce the partial width
$\Gamma(h\rightarrow Z\gamma)$, which are anti-correlated. With reasonable
values of the relevant free parameters, the vector bileptons can explain the
$LHC$ data for the $\gamma\gamma$ signal. If the $CMS$ data persists, the value
of the free parameters $ \lambda_{2}$ and $ \lambda_{3}$ should be severe
constrained.


title: Topological influence and back-action between topological excitations

abstract:
  Topological objects can influence each other if the underlying homotopy
groups are non-Abelian. Under such circumstances, the topological charge of
each individual object is no longer a conserved quantity and can be transformed
to each other. Yet, we can identify the conservation law by considering the
back-action of topological influence. We develop a general theory of
topological influence and back-action based on the commutators of the
underlying homotopy groups. We illustrate the case of the topological influence
of a half-quantum vortex on the sign change of a point defect and point out
that the topological back-action from the point defect is such twisting of the
vortex that the total twist of the vortex line carries the change in the
point-defect charge to conserve the total charge. We use this theory to
classify charge transfers in condensed matter systems and show that a
non-Abelian charge transfer can be realized in a spin-2 Bose-Einstein
condensate.


title:
Matrix group structure and Markov invariants in the strand symmetric
  phylogenetic substitution model

abstract:
  We consider the continuous-time presentation of the strand symmetric
phylogenetic substitution model (in which rate parameters are unchanged under
nucleotide permutations given by Watson-Crick base conjugation). Algebraic
analysis of the model's underlying structure as a matrix group leads to a
change of basis where the rate generator matrix is given by a two-part block
decomposition. We apply representation theoretic techniques and, for any
(fixed) number of phylogenetic taxa $L$ and polynomial degree $D$ of interest,
provide the means to classify and enumerate the associated Markov invariants.
In particular, in the quadratic and cubic cases we prove there are precisely
1/3$(3^L+(-1)^L)$ and $6^{L-1}$ linearly independent Markov invariants,
respectively. Additionally, we give the explicit polynomial forms of the Markov
invariants for (i) the quadratic case with any number of taxa $L$, and (ii) the
cubic case in the special case of a three-taxa phylogenetic tree. We close by
showing our results are of practical interest since the quadratic Markov
invariants provide independent estimates of phylogenetic distances based on (i)
substitution rates within Watson-Crick conjugate pairs, and (ii) substitution
rates across conjugate base pairs.

categories: q-bio.PE math.RT math.ST q-bio.QM stat.TH


title: Effect of strong magnetic fields on the pasta phase structure

abstract:
  The effect of strong magnetic fields on the properties of the pasta
structures is calculated within a Thomas Fermi approach using relativistic mean
field models to modulate stellar matter. It is shown how quantities such as the
size of the clusters and Wigner-Seitz cells, the surface tension and the
transition between configurations are affected. It is expected that these
effects may give rise to large stresses in the pasta phase if the local
magnetic field suffers fluctuations.


title:
Multi-TGDR: a regularization method for multi-class classification in
  microarray experiments

abstract:
  Background
  With microarray technology becoming mature and popular, the selection and use
of a small number of relevant genes for accurate classification of samples is a
hot topic in the circles of biostatistics and bioinformatics. However, most of
the developed algorithms lack the ability to handle multiple classes, which
arguably a common application. Here, we propose an extension to an existing
regularization algorithm called Threshold Gradient Descent Regularization
(TGDR) to specifically tackle multi-class classification of microarray data.
When there are several microarray experiments addressing the same/similar
objectives, one option is to use meta-analysis version of TGDR (Meta-TGDR),
which considers the classification task as combination of classifiers with the
same structure/model while allowing the parameters to vary across studies.
However, the original Meta-TGDR extension did not offer a solution to the
prediction on independent samples. Here, we propose an explicit method to
estimate the overall coefficients of the biomarkers selected by Meta-TGDR. This
extension permits broader applicability and allows a comparison between the
predictive performance of Meta-TGDR and TGDR using an independent testing set.
  Results
  Using real-world applications, we demonstrated the proposed multi-TGDR
framework works well and the number of selected genes is less than the sum of
all individualized binary TGDRs. Additionally, Meta-TGDR and TGDR on the
batch-effect adjusted pooled data approximately provided same results. By
adding Bagging procedure in each application, the stability and good predictive
performance are warranted.
  Conclusions
  Compared with Meta-TGDR, TGDR is less computing time intensive, and requires
no samples of all classes in each study. On the adjusted data, it has
approximate same predictive performance with Meta-TGDR. Thus, it is highly
recommended.


title:
Analytic compactifications of C^2 part II - one irreducible curve at
  infinity

abstract:
  We classify 'primitive normal compactifications' of C^2 (i.e. normal analytic
surfaces containing C^2 for which the curve at infinity is irreducible),
compute the moduli space of these surfaces and their groups of auomorphisms. In
particular we show that in 'most' of these surfaces C^2 is 'rigidly embedded'.
As an application we give a description of 'embedded isomorphism classes' of
planar curves with one place at infinity. We also compute the canonical divisor
of these surfaces; it turns out that their log discrepancy is related to the
Frobenius number of the semigroup of poles along the curve at infinity. We use
the computation to classify Gorenstein primitive compactifications of C^2 with
rational and minimally elliptic singularities, extending a result of Brenton,
Drucker and Prins (Ann. of Math. Stud., vol 100, 1981). As another application
we characterize weighted projective spaces of the form P^2(1,1,q) in terms of
their 'log discrepancy' and 'index', generalizing a characterization of P^2 due
to Borisov (Journal of Algebraic Combinatorics, 2014).


title:
Magnetic induction dependence of the dispersion of magnetoplasmon in a
  two-dimensional electron gas with finite layer thickness

abstract:
  Magnetic induction dependence of the dispersion of longitudinal
magnetoplasmon in a two-dimensional electron gas with finite layer thickness
under a static uniform magnetic field normal to the layer plane is calculated
using the self-consistent linear response approximation. Two longitudinal
magnetoplasmon modes are obtained. The calculated dispersion agrees with the
experiment by Batke {\it et al.} [Phys. Rev. B {\bf 34}, 6951 (1986)].


title:
The impact of Type Ia supernova explosions on helium companions in the
  Chandrasekhar-mass explosion scenario

abstract:
  In the version of the SD scenario of SNe Ia studied here, a CO WD explodes
close to the Chandrasekhar limit after accreting material from a non-degenerate
He companion. In the present study, we employ the Stellar GADGET code to
perform 3D hydrodynamical simulations of the interaction of the SN Ia ejecta
with the He companion taking into account its orbital motion and spin. It is
found that only 2%--5% of the initial companion mass are stripped off from the
outer layers of He companions due to the SN impact. The dependence of the
unbound mass (or the kick velocity) on the orbital separation can be fitted in
good approximation by a power law for a given companion model. After the SN
impact, the outer layers of a He donor star are significantly enriched with
heavy elements from the low-expansion-velocity tail of SN Ia ejecta. The total
mass of accumulated SN-ejecta material on the companion surface reaches about >
10e-3 M_sun for different companion models. This enrichment with heavy elements
provides a potential way to observationally identify the surviving companion
star in SN remnants. Finally, by artificially adjusting the explosion energy of
the W7 explosion model, we find that the total accumulation of SN ejecta on the
companion surface is also dependent on the explosion energy with a power law
relation in good approximation.


title: The brightness and spatial distributions of terrestrial radio sources

abstract:
  Faint undetected sources of radio-frequency interference (RFI) might become
visible in long radio observations when they are consistently present over
time. Thereby, they might obstruct the detection of the weak astronomical
signals of interest. This issue is especially important for Epoch of
Reionisation (EoR) projects that try to detect the faint redshifted HI signals
from the time of the earliest structures in the Universe. We explore the RFI
situation at 30-163 MHz by studying brightness histograms of visibility data
observed with LOFAR, similar to radio-source-count analyses that are used in
cosmology. An empirical RFI distribution model is derived that allows the
simulation of RFI in radio observations. The brightness histograms show an RFI
distribution that follows a power-law distribution with an estimated exponent
around -1.5. With several assumptions, this can be explained with a uniform
distribution of terrestrial radio sources whose radiation follows existing
propagation models. Extrapolation of the power law implies that the current
LOFAR EoR observations should be severely RFI limited if the strength of RFI
sources remains strong after time integration. This is in contrast with actual
observations, which almost reach the thermal noise and are thought not to be
limited by RFI. Therefore, we conclude that it is unlikely that there are
undetected RFI sources that will become visible in long observations.
Consequently, there is no indication that RFI will prevent an EoR detection
with LOFAR.


title:
Multiband Diagnostics of Unidentified 1FGL Sources with Suzaku and Swift
  X-ray Observations

abstract:
  We have analyzed all the archival X-ray data of 134 unidentified (unID)
gammaray sources listed in the first Fermi/LAT (1FGL) catalog and subsequently
followed up by Swift/XRT. We constructed the spectral energy distributions
(SEDs) from radio to gamma-rays for each X-ray source detected, and tried to
pick up unique objects that display anomalous spectral signatures. In these
analysis, we target all the 1FGL unID sources, using updated data from the
second Fermi/LAT (2FGL) catalog on their LAT position and spectra. We found
several potentially interesting objects, particularly three sources, 1FGL
J0022.2-1850, 1FGL J0038.0+1236 and 1FGL J0157.0-5259, which were then more
deeply observed with Suzaku as a part of an AO7 program in 2012. We
successfully detected an X-ray counterpart for each source whose X-ray spectra
were well fitted by a single power-law function. The positional coincidence
with a bright radio counterpart (currently identified as AGN) in the 2FGL error
circles suggests these are definitely the X-ray emission from the same AGN, but
their SEDs show a wide variety of behavior. In particular, the SED of 1FGL
J0038.0+1236 is difficult to be explained by conventional emission models of
blazars. The source 1FGL J0022.2-1850 may be in a transition state between a
low-frequency peaked BL Lac and a high-frequency peaked BL Lac object, and 1FGL
J0157.0-5259 could be a rare kind of extreme blazar. We discuss the possible
nature of these three sources observed with Suzaku, together with the X-ray
identification results and SEDs of all 134 sources observed with Swift/XRT.


title: Random Rates for 0-Extension and Low-Diameter Decompositions

abstract:
  Consider the problem of partitioning an arbitrary metric space into pieces of
diameter at most \Delta, such every pair of points is separated with relatively
low probability. We propose a rate-based algorithm inspired by
multiplicatively-weighted Voronoi diagrams, and prove it has optimal
trade-offs. This also gives us another logarithmic approximation algorithm for
the 0-extension problem.


title:
Characterizations and construction methods for linear functional-repair
  storage codes

abstract:
  We present a precise characterization of linear functional-repair storage
codes in terms of {\em admissible states/}, with each state made up from a
collection of vector spaces over some fixed finite field. To illustrate the
usefulness of our characterization, we provide several applications. We first
describe a simple construction of functional-repair storage codes for a family
of code parameters meeting the cutset bound outside the MBR and MSR points;
these codes are conjectured to have optimal rate with respect to their repair
locality. Then, we employ our characterization to develop a construction method
to obtain functional repair codes for given parameters using symmetry groups,
which can be used both to find new codes and to improve known ones. As an
example of the latter use, we describe a beautiful functional-repair storage
code that was found by this method, with parameters belonging to the family
investigated earlier, which can be specified in terms of only eight different
vector spaces.


title: Vortex pinning by surface geometry in superfluid helium

abstract:
  We present measurements of how a single vortex line in superfluid helium
interacts with a macroscopic bump on the chamber wall. At a general level our
measurements confirm computational work on vortex pinning by a hemispherical
bump, but not all the details agree. Rather than observing a unique pin
location, we find that a given applied velocity field can support pinning at
multiple sites along the bump, both near its apex and near its edge. We also
find that pinning is less favorable than expected. A vortex can pass near or
even traverse the bump itself with or without pinning, depending on its path of
approach to the bump.


title: Impacts of non-geometric moduli on effective theory of 5D supergravity

abstract:
  5D supergravity generically has non-geometric moduli other than the radion
that belong to 5D vector multiplets. We summarize the impacts of such moduli on
4D effective theory of 5D supergravity on S^1/Z_2. We mainly discuss the
structure of the effective Kahler potential including the one-loop quantum
corrections. As an illustrative example, we construct a model in which the size
of the extra dimension is stabilized at an exponentially large value compared
to the Planck length, which is similar to the LARGE volume scenario in string
theory.


title:
Kinetic Monte Carlo Simulation of Electrodeposition using the
  Embedded-Atom Method

abstract:
  A kinetic Monte Carlo (KMC) method is presented to simulate the
electrodeposition of a metal on a single crystal surface of the same metal
under galvanostatic conditions. This method utilizes the multi-body
embedded-atom method (EAM) potential to characterize the interactions of metal
atoms and adatoms. The KMC method accounts for deposition and surface diffusion
processes including hopping, atom exchange and step-edge atom exchange.
Steady-state deposition configurations obtained using the KMC method are
validated by comparison with the structures obtained through the use of
molecular dynamics (MD) simulations to relax KMC constraints. The results of
this work support the use of the proposed KMC method to simulate
electrodeposition processes at length (microns) and time (seconds) scales that
are not feasible using other methods.


title:
Automated One-loop Computation in Quarkonium Process within NRQCD
  Framework

abstract:
  In last decades, it has been realized that the next-to-leading order
corrections may become very important, and sometimes requisite, for some
processes involving quarkoinum production or decay, e.g., $e^+e^- \to J/\psi +
\eta_c$ and $J/\psi \to 3\gamma$. In this article, we review some basic steps
to perform automated one-loop computations in quarkonium process within the
Non-relativistic Quantum Chromodynamics (NRQCD) factorization framework, and we
give an introduction to some related public tools or packages and their usages
in each step. We start from generating Feynman diagrams and amplitudes with
\textsc{FeynArts} for the quarkonium process, performing Dirac- and Color-
algebras simplifications using \textsc{FeynCalc} and \textsc{FeynCalcFormLink},
and then to doing partial fractions on the linear-dependent propagators by
\textsc{APart}, and finally to reducing the Tensor Integrals (TI) into Scalar
Integrals (SI) or Master Integrals (MI) using Integration-By-Parts (IBP) method
with the help of \textsc{Fire}. We will use a simple concrete example to
demonstrate the basic usages of the corresponding packages or tools in each
step.


title: New Method to Estimate Binary Mass Ratios by Using Superhumps

abstract:
  We propose a new dynamical method to estimate binary mass ratios by using the
period of superhumps in SU UMa-type dwarf novae during the growing stage (the
stage A superhumps). This method is based on a working hypothesis in which the
period of the superhumps at the growing stage is determined by the dynamical
precession rate at the 3:1 resonance radius, a picture suggested in our new
interpretation of the superhump period evolution during the superoutburst
(Osaki, Kato 2013, arXiv:1305.5877). By comparison with the objects with known
mass ratios, we show that our method can provide sufficiently accurate mass
ratios comparable to those obtained by quiescent eclipse observations. This
method is very advantageous in that it requires neither eclipses, nor an
experimental calibration. It is particularly suited for exploring the low
mass-ratio end of the evolution of cataclysmic variables, where the secondary
is undetectable by conventional methods. Our analysis suggests that previous
estimates of mass ratios using superhump periods during superoutburst were
systematically underestimated for low mass-ratio systems and we provided a new
calibration. It suggests that most of WZ Sge-type dwarf novae have secondaries
close to the border of the lower main-sequence and brown dwarfs, and most of
the objects have not yet reached the evolutionary stage of period bouncers. Our
result is not in contradiction with an assumption that the observed minimum
period (~77 min) of ordinary hydrogen-rich cataclysmic variables is indeed the
period minimum. We highlight the importance of early observation of stage A
superhumps and propose a future desirable strategy of observation.


title: The Second Parameter Problem(s)

abstract:
  The Second Parameter (2ndP) Problem recognizes the remarkable role played by
horizontal branch (HB) morphology in the development of our understanding of
globular clusters, and the Galaxy, over the last 50 years. I will describe the
historical development of the 2ndP and discuss recent advances that are finally
providing some answers. I will discuss how the controversies surrounding the
nature of the 2ndP can be reconciled if we acknowledge that there are actually
two distinct problems with entirely different solutions.


title:
Clustered Geometries Exploiting Quantum Coherence Effects for Efficient
  Energy Transfer in Light Harvesting

abstract:
  Elucidating quantum coherence effects and geometrical factors for efficient
energy transfer in photosynthesis has the potential to uncover non-classical
design principles for advanced organic materials. We study energy transfer in a
linear light-harvesting model to reveal that dimerized geometries with strong
electronic coherences within donor and acceptor pairs exhibit significantly
improved efficiency, which is in marked contrast to predictions of the
classical F\"orster theory. We reveal that energy tuning due to coherent
delocalization of photoexcitations is mainly responsible for the efficiency
optimization. This coherence-assisted energy-tuning mechanism also explains the
energetics and chlorophyll arrangements in the widely-studied
Fenna-Matthews-Olson complex. We argue that a clustered network with rapid
energy relaxation among donors and resonant energy transfer from donor to
acceptor states provides a basic formula for constructing efficient
light-harvesting systems, and the general principles revealed here can be
generalized to larger systems and benefit future innovation of efficient
molecular light-harvesting materials.

categories: physics.bio-ph cond-mat.mes-hall physics.chem-ph quant-ph


title: A Novel Equation based Classifier for Detecting Human in Images

abstract:
  Shape based classification is one of the most challenging tasks in the field
of computer vision. Shapes play a vital role in object recognition. The basic
shapes in an image can occur in varying scale, position and orientation. And
specially when detecting human, the task becomes more challenging owing to the
largely varying size, shape, posture and clothing of human. So, in our work we
detect human, based on the head-shoulder shape as it is the most unvarying part
of human body. Here, firstly a new and a novel equation named as the Omega
Equation that describes the shape of human head-shoulder is developed and based
on this equation, a classifier is designed particularly for detecting human
presence in a scene. The classifier detects human by analyzing some of the
discriminative features of the values of the parameters obtained from the Omega
equation. The proposed method has been tested on a variety of shape dataset
taking into consideration the complexities of human head-shoulder shape. In all
the experiments the proposed method demonstrated satisfactory results.


title:
Proof search for propositional abstract separation logics via labelled
  sequents

abstract:
  Separation logics are a family of extensions of Hoare logic for reasoning
about programs that mutate memory. These logics are "abstract" because they are
independent of any particular concrete memory model. Their assertion languages,
called propositional abstract separation logics, extend the logic of (Boolean)
Bunched Implications (BBI) in various ways.
  We develop a modular proof theory for various propositional abstract
separation logics using cut-free labelled sequent calculi. We first extend the
cut-fee labelled sequent calculus for BBI of Hou et al to handle Calcagno et
al's original logic of separation algebras by adding sound rules for
partial-determinism and cancellativity, while preserving cut-elimination. We
prove the completeness of our calculus via a sound intermediate calculus that
enables us to construct counter-models from the failure to find a proof. We
then capture other propositional abstract separation logics by adding sound
rules for indivisible unit and disjointness, while maintaining completeness. We
present a theorem prover based on our labelled calculus for these propositional
abstract separation logics.


title:
Conserving and Gapless Hartree-Fock-Bogoliubov theory for 3D dilute Bose
  gas at finite temperature

abstract:
  The energy spectrum for the three dimensional Bose gas in Bose-Einstein
Condensation phase is calculated with Modified Hartree-Fock-Bogoliubov theory,
which is both conserving and gapless. From Improved $\Phi -$% derivable theory,
the diagrams needed to preserve Ward-Takahashi Identity are resummed in a
systematic and nonperturbative way. The results show significant discrepancies
with Popov theory at finite temperature. It is valid up to the critical
temperature where the dispersion relation of the low energy excitation spectrum
changes from linear to quadratic. Because of the repulsive interaction, the
critical temperature has a positive shift from that of idea gas, which is in
accordance with the result from the previous calculations in the uncondensed
phase.


title: On decompositions of trigonometric polynomials

abstract:
  Let $\mathbb R_t[\theta]$ be the ring generated over $\mathbb R$ by
$\cos\theta$ and $\sin\theta$, and $\mathbb R_t(\theta)$ be its quotient field.
In this paper we study the ways in which an element p of $\mathbb R_t[\theta]$
can be decomposed into a composition of functions of the form $p=R(q),$ where
$\mathbb R\in \mathbb R(x)$ and $q\in \mathbb R_t(\theta)$. In particular, we
describe all possible solutions of the functional equation $R_1(q_1)=R_2(q_2)$,
where $R_1, R_2 \in \mathbb R[x]$ and $q_1,q_2\in \mathbb R_t[\theta].$


title: Locomotion of microspheres for super-resolution imaging

abstract:
  Super-resolution imaging using sub-diffraction field localization by micron
sized transparent beads (microspheres) was recently demonstrated [1]. Practical
applications in microscopy require control over the positioning of the
microspheres. We present a simple method of positioning and controllable
movement of a microsphere by using a glass micropipette. This allows
sub-diffraction imaging at arbitrary points in three dimensions, as well as the
ability to track moving objects. The results are relevant to a broad scope of
applications, including sample inspection, and bio-imaging.


title:
Transition from ultrafast laser photo-electron emission to space charge
  limited current in a 1D gap

abstract:
  A one-dimensional (1D) model has been constructed to study the transition of
the time-dependent ultrafast laser photo-electron emission from a flat metallic
surface to the space charge limited (SCL) current, including the effect of
non-equilibrium laser heating on metals at the ultrafast time scale. At a high
laser field, it is found that the space charge effect cannot be ignored and the
SCL current emission is reached at a lower value predicted by a short pulse SCL
current model that assumed a time-independent emission process. The threshold
of the laser field to reach the SCL regime is determined over a wide range of
operating parameters. The calculated results agree well with particle-in-cell
(PIC) simulation. It is found that the space charge effect is more important
for materials with lower work function like tungsten (4.4 eV) as compared to
gold (5.4 eV). However for a flat surface, both materials will reach the space
charge limited regime at the sufficiently high laser field such as $>$ 5 GV/m
with a laser pulse length of tens to one hundred femtoseconds.


title:
Random variables with an invariant random shift in compact metrisable
  abelian groups

abstract:
  The main result of this paper states that for independent random variables
$X, Y$ taking values in a compact metrisable abelian group, $X + Y$ has the
same distribution as $X$, if and only if there exists a compact subgroup $A$
such that $P(Y\in A)=1$ and $X + a$ has the same distribution as $X$ for all
$a\in A$. As a conclusion from the above it is shown that for independent
random variables $X, Y$ such that $X+Y$ has the same distribution as $X$, $X+Y$
and $Y$ are also independent. It becomes also apparent that the distribution of
$X$ is the Haar measure (uniform distribution) if for each open set $U$,
$P(Y\in U) > 0$.


title:
New discrete method for investigating the response properties in finite
  electric field

abstract:
  In this paper we develop a new discrete method for calculating the dielectric
tensor and Born effective charge tensor in finite electric field by using
Berry's phase and the gauge invariance. We present a new method to overcome
non-periodicity of the potential in finite electric field due to the gauge
invariance, and construct the dielectric tensor and Born effective charge
tensor that satisfy translational symmetry in finite electric field. In order
to demonstrate the correctness of this method, we also perform calculations for
the semiconductors AlAs and GaAs under the finite electric field to compare
with the preceding method and the experiment.


title:
Performance comparison of State-of-the-art Missing Value Imputation
  Algorithms on Some Bench mark Datasets

abstract:
  Decision making from data involves identifying a set of attributes that
contribute to effective decision making through computational intelligence. The
presence of missing values greatly influences the selection of right set of
attributes and this renders degradation in classification accuracies of the
classifiers. As missing values are quite common in data collection phase during
field experiments or clinical trails appropriate handling would improve the
classifier performance. In this paper we present a review of recently developed
missing value imputation algorithms and compare their performance on some bench
mark datasets.


title: Tractability results for the weighted star-discrepancy

abstract:
  The weighted star-discrepancy has been introduced by Sloan and
Wo{\'z}niakowski to reflect the fact that in multidimensional integration
problems some coordinates of a function may be more important than others. It
provides upper bounds for the error of multidimensional numerical integration
algorithms for functions belonging to weighted function spaces of Sobolev type.
In the present paper, we prove several tractability results for the weighted
star-discrepancy. In particular, we obtain rather sharp sufficient conditions
under which the weighted star-discrepancy is strongly tractable. The proofs are
probabilistic, and use empirical process theory.


title: Kinetic Energy Plus Penalty Functions for Sparse Estimation

abstract:
  In this paper we propose and study a family of sparsity-inducing penalty
functions. Since the penalty functions are related to the kinetic energy in
special relativity, we call them \emph{kinetic energy plus} (KEP) functions. We
construct the KEP function by using the concave conjugate of a
$\chi^2$-distance function and present several novel insights into the KEP
function with $q=1$. In particular, we derive a thresholding operator based on
the KEP function, and prove its mathematical properties and asymptotic
properties in sparsity modeling. Moreover, we show that a coordinate descent
algorithm is especially appropriate for the KEP function. Additionally, we
discuss the relationship of KEP with the penalty functions $\ell_{1/2}$ and
MCP. The theoretical and empirical analysis validates that the KEP function is
effective and efficient in high-dimensional data modeling.


title: Uncertainty and absence of arbitrage opportunity

abstract:
  It is shown that absence of arbitrage opportunity in financial markets is a
particular case of existence of uncertainty in decision system. Absence of
arbitrage opportunity is considered in the sense of the Arrow-Debreu model of
financial market with a riskless asset, while uncertainty (or ambiguity) is
defined on the basis of the principle of internal coherence of M. Allais.


title:
Analytical expression for the harmonic Hall voltages in evaluating spin
  orbit torques

abstract:
  Solid understanding of current induced torques is key to the development of
current and voltage controlled magnetization dynamics in ultrathin magnetic
heterostructures. A versatile technique is needed to evaluate such torques in
various systems. Here we examine the adiabatic (low frequency) harmonic Hall
voltage measurement that has been recently developed to study current induced
effective field that originate from the spin orbit effects. We analytically
derive a form that can be used to evaluate the harmonic Hall voltages and
extract relevant parameters in two representative systems, i.e. out of plane
and in-plane magnetized systems. Contributions from the anomalous Hall and
planar Hall effects are considered.


title:
Probing Physics beyond the Standard Model with He/Xe clock comparison
  experiments

abstract:
  The comparison of the free precession of co-located 3He-129Xe spins (clock
comparison) enables us to search for very tiny nonmagnetic spin interactions.
With our setup we could establish new limits for Lorentz invariance violating
interactions of spins with a relic background field which permeates the
Universe and points in a preferred direction in space.


title: On one stable birational invariant

abstract:
  This is an expository article, which contributes to the Proceedings of the
conference "Groups of Automorphisms in Birational and Affine Geometry", held in
Trento in 2012. We propose that (rational) fibrations on the projective space
$\p^n$ by (birationally) Abelian hypersurfaces, for an arbitrary $n\ge 2$,
provide an obstruction to stable rationality of algebraic varieties. We discuss
the evidence for this proposition and derive some (almost straightforward)
corollaries from it.


title:
Stochastic Target Games and Dynamic Programming via Regularized
  Viscosity Solutions

abstract:
  We study a class of stochastic target games where one player tries to find a
strategy such that the state process almost-surely reaches a given target, no
matter which action is chosen by the opponent. Our main result is a geometric
dynamic programming principle which allows us to characterize the value
function as the viscosity solution of a non-linear partial differential
equation. Because abstract mea-surable selection arguments cannot be used in
this context, the main obstacle is the construction of measurable
almost-optimal strategies. We propose a novel approach where smooth
supersolutions are used to define almost-optimal strategies of Markovian type,
similarly as in ver-ification arguments for classical solutions of
Hamilton--Jacobi--Bellman equations. The smooth supersolutions are constructed
by an exten-sion of Krylov's method of shaken coefficients. We apply our
results to a problem of option pricing under model uncertainty with different
interest rates for borrowing and lending.


title: Characterising a Higgs-like resonance at the LHC

abstract:
  We present the implementation of an effective lagrangian via FeynRules,
featuring bosons X(J^P) with various assignments of spin/parity J^P = 0^+, 0^-,
1^+, 1^-, or 2^+, that allows one to perform characterisation studies of the
boson recently discovered at the LHC, for all the relevant channels and in a
consistent, systematic and accurate way.


title:
Global behavior of the Solutions to a Class of Nonlinear, Singular
  Second Order ODE

abstract:
  In this paper the initial value problem and global properties of solutions
are studied for the scalar second order ODE: $ (|u'|^{l}u')' + c|u'|^{\alpha}u'
+ d|u|^\beta u=0$, where $\alpha,\beta,l,c, d$ are positive constants. In
particular, existence, uniqueness and regularity as well as optimal decay rates
of solutions to 0 are obtained depending on the various parameters, and the
oscillatory or non-oscillatory behavior is elucidated.


title: Graphs of quantum groups and K-amenability

abstract:
  Building on a construction of J-P. Serre, we associate to any graph of
C*-algebras a maximal and a reduced fundamental C*-algebra and use this theory
to construct the fundamental quantum group of a graph of discrete quantum
groups. This construction naturally gives rise to a quantum Bass-Serre tree
which can be used to study the K-theory of the fundamental quantum group. To
illustrate the properties of this construction, we prove that if all the vertex
qantum groups are amenable, then the fundamental quantum group is K-amenable.
This generalizes previous results of P. Julg, A. Valette, R. Vergnioux and the
first author.


title: A binomial splitting process in connection with corner parking problems

abstract:
  A special type of binomial splitting process is studied. Such a process can
be used to model a high-dimensional corner parking problem, as well as the
depth of random PATRICIA tries (a special class of digital tree data
structures). The later also has natural interpretations in terms of distinct
values in iid geometric random variables and the occupancy problem in urn
models. The corresponding distribution is marked by logarithmic mean and
bounded variance, which is oscillating, if the binomial parameter $p$ is not
equal to 1/2, and asymptotic to 1 in the unbiased case. Also, the limiting
distribution does not exist owing to periodic fluctuations.


title:
Correct Solvability, Embedding Theorems and Separability for the
  Sturm-Liouville Equation

abstract:
  We consider the equation - y"(x)+q(x)y(x)=f(x), x\in R and the weighted
function space S_p^{(2)}(R,q)=\{y\in
AC_{\loc}^{(1)}(R):\|y"-qy\|_p+\|q^{1/p}y\|_p<\infty\}; p\in[1,\infty), f\in
L_p(R)$ and $0\le q\in L_1^{\loc}(R)$. We show that there exists an embedding
S_p^{(2)}(R,q)\hookrightarrow L_p(R) if and only if equation above is correctly
solvable in $L_p(R).


title: Efficient Range Reporting of Convex Hull

abstract:
  We consider the problem of reporting convex hull points in an orthogonal
range query in two dimensions. Formally, let $P$ be a set of $n$ points in
$\mathbb{R}^{2}$. A point lies on the convex hull of a point set $S$ if it lies
on the boundary of the minimum convex polygon formed by $S$. In this paper, we
are interested in finding the points that lie on the boundary of the convex
hull of the points in $P$ that also fall with in an orthogonal
range$[x_{lt},x_{rt}]\times{}[y_b, y_t]$. We propose a $O(n \log^{2} n) $ space
data structure that can support reporting points on a convex hull inside an
orthogonal range query, in time $O(\log^{3} n + h)$. Here $h$ is the size of
the output. This work improves the result of (Brass et al. 2013) \cite{brass}
that builds a data structure that uses $O(n \log^{2} n)$ space and has a
$O(\log^{5} n + h)$ query time. Additionally, we show that our data structure
can be modified slightly to solve other related problems. For instance, for
counting the number of points on the convex hull in an orthogonal query
rectangle, we propose an $O(n \log^{2}n)$ space data structure that can be
queried upon in $O(\log^{3} n)$ time. We also propose a $O(n \log^{2} n) $
space data structure that can compute the $area$ and $perimeter$ of the convex
hull inside an orthogonal range query in $O(\log^{3} n$) time.


title:
Optimal Primary-Secondary user Cooperation Policies in Cognitive Radio
  Networks

abstract:
  In cognitive radio networks, secondary users (SUs) may cooperate with the
primary user (PU), so that the success probability of PU transmissions are
improved, while SUs obtain more transmission opportunities. Thus, SUs have to
take intelligent decisions on whether to cooperate or not and with what power
level, in order to maximize their throughput subject to average power
constraints. Cooperation policies in this framework require the solution of a
constrained Markov decision problem with infinite state space. In our work, we
restrict attention to the class of stationary policies that take randomized
decisions in every time slot based only on spectrum sensing. The proposed class
of policies is shown to achieve the same set of SU rates as the more general
policies, and enlarge the stability region of PU queue. Moreover, algorithms
for the distributed calculation of the set of probabilities used by the
proposed class of policies are presented.


title:
Analytic Study of First-Order Phase Transition in Holographic
  Superconductor and Superfluid

abstract:
  We use the matching method to investigate the first-order phase transition in
holographic superconductor and superfluid. We first use the simple holographic
superconductor model to describe the matching method and mention how to see the
first-order phase transition. Next, we study the holographic superconductor
with St\"uckelberg term and see that the analytic results indicate the
existence of first-order phase transition. Finally, we study the holographic
superfluid and show that the first-order phase transition can be found for some
values of parameters. We determine the critical value analytically and compare
it with the previous numerical result.


title:
Comment on "System-environment coupling derived by Maxwell's boundary
  conditions from the weak to the ultrastrong light-matter coupling regime"

abstract:
  In a recent work [arXiv:1301.3960], Bamba and Ogawa developed a microscopic
model describing the field of a photonic cavity coupled to a matter
exciton-like resonance. One of the results they obtain studying such a model is
that, in the ultrastrong coupling regime, usually safe approaches can give
wrong results for the dissipation rates of the polaritonic excitations. In
particular the dissipation rates calculated applying the rotating wave
approximation on the system-environment coupling qualitatively differ from the
ones calculated using a microscopic theory based on the quantum electrodynamics
for dielectric media. Here I show that this result is an artifact, caused by an
inconsistent application of the rotating wave approximation and by a
questionable parameter choice.


title: The Neutron Star Born in the Antlia Supernova Remnant

abstract:
  Among all known young nearby neutron stars, we search for the neutron star
that was born in the same supernova event that formed the Antlia supernova
remnant (SNR). We also look for a runaway star that could have been the former
companion to the neutron star (if it exists) and then got ejected due to the
same supernova. We find the pulsar PSR J0630-2834 to be the best candidate for
a common origin with the Antlia SNR. In that scenario the SNR is ~1.2 Myr old
and is presently located at a distance of ~138 pc. We consider the runaway star
HIP 47155 a former companion candidate to PSR J0630-2834. The encounter time
and place is consistent with both stars being ejected from the Antlia SNR. We
measured the radial velocity of HIP 47155 as 32.42 +/- 0.70km/s.


title: Robust Quantitative Comparative Statics for a Multimarket Paradox

abstract:
  We introduce a quantitative approach to comparative statics that allows to
bound the maximum effect of an exogenous parameter change on a system's
equilibrium. The motivation for this approach is a well known paradox in
multimarket Cournot competition, where a positive price shock on a monopoly
market may actually reduce the monopolist's profit. We use our approach to
quantify for the first time the worst case profit reduction for multimarket
oligopolies exposed to arbitrary positive price shocks. For markets with affine
price functions and firms with convex cost technologies, we show that the
relative profit loss of any firm is at most 25% no matter how many firms
compete in the oligopoly. We further investigate the impact of positive price
shocks on total profit of all firms as well as on social welfare. We find tight
bounds also for these measures showing that total profit and social welfare
decreases by at most 25% and 16.6%, respectively. Finally, we show that in our
model, mixed, correlated and coarse correlated equilibria are essentially
unique, thus, all our bounds apply to these game solutions as well.


title: Minimal Length and Small Scale Structure of Spacetime

abstract:
  Many generic arguments support the existence of a minimum spacetime interval
$L_0$. Such a "zero-point" length can be naturally introduced in a locally
Lorentz invariant manner via Synge's world function bi-scalar $\Omega(p,P)$
which measures squared geodesic interval between spacetime events $p$ and $P$.
I show that there exists a \emph{non-local} deformation of spacetime geometry
given by a \emph{disformal} coupling of metric to the bi-scalar $\Omega(p,P)$,
which yields a geodesic interval of $L_0$ in the limit $p \rightarrow P$.
Locality is recovered when $\Omega(p,P) >> L_0^2/2$. I discuss several
conceptual implications of the resultant small-scale structure of spacetime for
QFT propagators as well as spacetime singularities.


title: On the Mailbox Problem

abstract:
  The Mailbox Problem was described and solved by Aguilera, Gafni, and Lamport
in their 2010 DC paper with an algorithm that uses two flag registers that
carry 14 values each. An interesting problem that they ask is whether there is
a mailbox algorithm with smaller flag values. We give a positive answer by
describing a mailbox algorithm with 6 and 4 values in the two flag registers.


title: On the spaces of $\lambda-$ convergent and bounded series

abstract:
  The main purpose of this study is to introduce the spaces $cs^{\lambda},
cs_0^{\lambda}$ and $bs^{\lambda}$ which are $BK-$spaces of non-absolute type.
We prove that these spaces are linearly isomorphic to the spaces $cs, cs_0$ and
$bs$, respectively and derive some inclusion relations. Additionally, their
Schauder bases have been constructed and the $\alpha-,\beta-$ and $\gamma-$
duals of these spaces have been computed. Finally, we characterize some matrix
classes from the spaces $cs^{\lambda}, cs_0^{\lambda}$ and $bs^{\lambda}$ to
spaces $\ell_p, c$ and $c_0$, where $1\leq p\leq\infty$ .


title:
Nanophotonic Filters and Integrated Networks in Flexible 2D Polymer
  Photonic Crystals

abstract:
  Polymers have appealing optical, biochemical, and mechanical qualities,
including broadband transparency, ease of functionalization, and
biocompatibility. However, their low refractive indices have precluded
wavelength-scale optical confinement and nanophotonic applications in polymers.
Here, we introduce a suspended polymer photonic crystal (SPPC) architecture
that enables the implementation of nanophotonic structures typically limited to
high-index materials. Using the SPPC platform, we demonstrate nanophotonic
band-edge filters, waveguides, and nanocavities featuring quality ($Q$) factors
exceeding $2,300$ and mode volumes ($V_{mode}$) below
\textbf{$1.7(\lambda/n)^{3}$}. The unprecedentedly high $Q/V_{mode}$ ratio
results in a spectrally selective enhancement of radiative transitions of
embedded emitters via the cavity Purcell effect with an enhancement factor
exceeding 100. Moreover, the SPPC architecture allows straightforward
integration of nanophotonic networks, shown here by a waveguide-coupled cavity
drop filter with sub-nanometer spectral resolution. The nanoscale optical
confinement in polymer promises new applications ranging from optical
communications to organic opto-electronics, and nanophotonic polymer sensors.


title:
Spin rectification in thermally driven XXZ spin chain via the
  spin-Seebeck effect

abstract:
  We study the phenomenon of spin-current rectification in a one-dimensional
XXZ spin chain in the presence of a thermal drive. In our model a pure spin
current is generated by a temperature difference between two harmonic heat
baths which in turn creates a spin voltage via the spin-Seebeck effect. Along
with a local spin-current operator definition and the nonequilibrium modified
Redfield solution we study the spin-rectification ratio as a function of system
size and external magnetic field. Intriguing effects are observed at low
temperatures such as oscillations with system size and high range of tunability
with external magnetic field making magnetic insulators, which are well
described by the XXZ model, ideal candidates to build spin devices based on
rectification.


title: Quantum cosmology and late-time singularities

abstract:
  The development of dark energy models has stimulated interest to cosmological
singularities, which differ from the traditional Big Bang and Big Crunch
singularities. We review a broad class of phenomena connected with soft
cosmological singularities in classical and quantum cosmology. We discuss the
classification of singularities from the geometrical point of view and from the
point of view of the behaviour of finite size objects, crossing such
singularities. We discuss in some detail quantum and classical cosmology of
models based on perfect fluids (anti-Chaplygin gas and anti-Chaplygin gas plus
dust), of models based on the Born-Infeld-type fields and of the model of a
scalar field with a potential inversely proportional to the field itself. We
dwell also on the phenomenon of the phantom divide line crossing in the scalar
field models with cusped potentials. Then we discuss the Friedmann equations
modified by quantum corrections to the effective action of the models under
considerations and the influence of such modification on the nature and the
existence of soft singularities. We review also quantum cosmology of models,
where the initial quantum state of the universe is presented by the density
matrix (mixed state). Finally, we discuss the exotic singularities arising in
the brane-world cosmological models.


title:
Generalized Stirling permutations and forests: Higher-order Eulerian and
  Ward numbers

abstract:
  We define a new family of generalized Stirling permutations that can be
interpreted in terms of ordered trees and forests. We prove that the number of
generalized Stirling permutations with a fixed number of ascents is given by a
natural three-parameter generalization of the well-known Eulerian numbers. We
give the generating function for this new class of numbers and, in the simplest
cases, we find closed formulas for them and the corresponding row polynomials.
By using a non-trivial involution our generalized Eulerian numbers can be
mapped onto a family of generalized Ward numbers, forming a Riordan inverse
pair, for which we also provide a combinatorial interpretation.