title:
Reconstruction of Complex-Valued Fractional Brownian Motion Fields Based
  on Compressive Sampling and Its Application to PSF Interpolation in Weak
  Lensing Survey

abstract:
  A new reconstruction method of complex-valued fractional Brownian motion
(CV-fBm) field based on Compressive Sampling (CS) is proposed. The decay
property of Fourier coefficients magnitude of the fBm signals/ fields indicates
that fBms are compressible. Therefore, a few numbers of samples will be
sufficient for a CS based method to reconstruct the full field. The
effectiveness of the proposed method is showed by simulating, random sampling,
and reconstructing CV-fBm fields. Performance evaluation shows advantages of
the proposed method over boxcar filtering and thin plate methods. It is also
found that the reconstruction performance depends on both of the fBm's Hurst
parameter and the number of samples, which in fact is consistent with the CS
reconstruction theory. In contrast to other fBm or fractal interpolation
methods, the proposed CS based method does not require the knowledge of fractal
parameters in the reconstruction process; the inherent sparsity is just
sufficient for the CS to do the reconstruction. Potential applicability of the
proposed method in weak gravitational lensing survey, particularly for
interpolating non-smooth PSF (Point Spread Function) distribution representing
distortion by a turbulent field is also discussed.


title:
Reductions of the Navier-Stokes-Allen-Cahn and the
  Navier-Stokes-Cahn-Hilliard equations

abstract:
  This paper studies two well-known models for two-phase fluid flow at constant
temperature, the isothermal Navier-Stokes-Allen-Cahn and the isothermal
Navier-Stokes-Cahn-Hilliard equations, both of which consist of equations for
the (total) fluid density rho, the (mass-averaged)velocity u and the
concentration (of one of the phases,) c. Assuming in either case that both
phases are incompressible with different densities, each of the models is shown
to reduce to a system of evolution equations in rho and u alone. In the case of
the Navier-Stokes-Allen-Cahn model, this reduced system is the classical
Navier-Stokes-Korteweg model. The reduced system resulting from the
Navier-Stokes-Cahn-Hilliard equations is a novel `integro'-differential system
in which a non-local operator acts on the divergence of the velocity.


title:
Extension of Minimal Fermionic Dark Matter Model : A Study with Two
  Higgs Doublet Model

abstract:
  We explore a fermionic dark matter model with a possible extension of
Standard Model (SM) of particle physics into two Higgs doublet model. Higgs
doublets couple to the singlet fermionic dark matter (FDM) through a non
renormalisable coupling providing a new physics scale. We explore the viability
of such dark matter candidate and constrain the model parameter space by
collider serach, relic density of DM, direct detection measurements of
DM-nucleon scattreing cross-section and with the experimentally obtained
results from indirect search of dark matter.


title: Face to phase with RU Lupi

abstract:
  We present new results on the classical T Tauri star RU Lupi based on three
observing runs collecting high-resolution spectra, complementary NIR spectra,
multicolour photometric data, and X-ray observations. The photospheric
absorption lines are weakened. This veiling becomes extremely strong on
occasion, and we show that this effect is due to narrow emission lines that
fill in the photospheric lines. The blue-shifted wings in the optical emission
lines of He I, attributed to a stellar wind, are remarkably stable in
equivalent width. In contrast, the red-shifted wings change dramatically in
strength depending on rotational phase. From the pattern of variability we
infer that these wings originate in accreting gas close to the star, and that
the accretion funnels are bent and trail the hot spot. Forbidden emission lines
are very stable over the entire observing period and originate in the disk
wind. A system of narrow blue-shifted absorption features seen in lines of Ca
II and Na I can be traced to a disk wind as well. Slightly blue-shifted
emission components are present in the forbidden lines and might be related to
a wide angle molecular disk wind.


title:
Random flights governed by Klein-Gordon-type partial differential
  equations

abstract:
  In this paper we study random flights in R^d with displacements possessing
Dirichlet distributions of two different types and uniformly oriented. The
randomization of the number of displacements has the form of a generalized
Poisson process whose parameters depend on the dimension d. We prove that the
distributions of the point X(t) and Y(t), t \geq 0, performing the random
flights (with the first and second form of Dirichlet intertimes) are related to
Klein-Gordon-type partial differential equations. Our analysis is based on
McBride theory of integer powers of hyper-Bessel operators. A special attention
is devoted to the three-dimensional case where we are able to obtain the
explicit form of the equations governing the law of X(t) and Y(t). In
particular we show that that the distribution of Y(t) satisfies a
telegraph-type equation with time-varying coefficients.


title:
Dark halos and elliptical galaxies as marginally stable dynamical
  systems

abstract:
  The origin of equilibrium gravitational configurations is sought in terms of
the stability of their trajectories, as described by the curvature of their
Lagrangian configuration manifold of particle positions --- a context in which
subtle spurious effects originating from the singularity in the two body
potential become particularly clear. We focus on the case of spherical systems,
which support only regular orbits in the collisionless limit, despite the
persistence of local exponential instability of $N$-body trajectories in the
anomalous case of discrete point particle representation even as $N \rightarrow
\infty$. When the singularity in the potential is removed, this apparent
contradiction disappears. In the absence of fluctuations, equilibrium
configurations generally correspond to positive scalar curvature, and thus
support stable trajectories. A null scalar curvature is associated with an
effective, averaged, equation of state describing dynamically relaxed
equilibria with marginally stable trajectories. The associated configurations
are quite similar to those of observed elliptical galaxies and simulated
cosmological halos, and are necessarily different from the systems dominated by
isothermal cores, expected from entropy maximization in the context of the
standard theory of violent relaxation. It is suggested that this is the case
because a system starting far from equilibrium does not reach a 'most probable
state' via violent relaxation, but that this process comes to an end as the
system finds and (settles in) a configuration where it can most efficiently
wash out perturbations. We explicitly test this interpretation by means of
direct simulations.


title:
Temperature - pressure phase diagram of CeCoSi: Pressure induced
  high-temperature phase

abstract:
  We have studied the temperature-pressure phase diagram of CeCoSi by
electrical-resistivity experiments under pressure. Our measurements revealed a
very unusual phase diagram. While at low pressures no dramatic changes and only
a slight shift of the Ne\'{e}l temperature $T_N$ ($\approx 10$ K) are observed,
at about 1.45 GPa a sharp and large anomaly, indicative of the opening of a
spin-density-wave (SDW) gap, appears at a comparatively high temperature $T_S
\approx 38$ K. With further increasing pressure $T_S$ shifts rapidly to low
temperatures and disappears at about 2.15 GPa, likely continuously in a quantum
critical point, but without evidence for superconductivity. Even more
surprisingly, we observed a clear shift of $T_S$ to higher temperatures upon
applying a magnetic field. We discuss two possible origins for $T_S$, either
magnetic ordering of Co or a meta-orbital type of transition of Ce.


title: A Clifford algebraic Approach to Line Geometry

abstract:
  In this paper we combine methods from projective geometry, Klein's model, and
Clifford algebra. We develop a Clifford algebra whose Pin group is a double
cover of the group of regular projective transformations. The Clifford algebra
we use is constructed as homogeneous model for the five-dimensional real
projective space $P^5(\mathbb{R})$ where Klein's quadric $M_2^4$ defines the
quadratic form. We discuss all entities that can be represented naturally in
this homogeneous Clifford algebra model. Projective automorphisms of Klein's
quadric induce projective transformations of $P^3(\mathbb{R})$ and vice versa.
Cayley-Klein geometries can be represented by Clifford algebras, where the
group of Cayley-Klein isometries is given by the Pin group of the corresponding
Clifford algebra. Therefore, we examine the versor group and study the
correspondence between versors and regular projective transformations
represented as $4\times 4$ matrices. Furthermore, we give methods to compute a
versor corresponding to a given projective transformation.


title: Lagrangian tori near resonances of near-integrable Hamiltonian systems

abstract:
  In this paper we study families of Lagrangian tori that appear in a
neighborhood of a resonance of a near-integrable Hamiltonian system. Such
families disappear in the "integrable" limit $\varepsilon\to 0$. Dynamics on
these tori is oscillatory in the direction of the resonance phases and rotating
with respect to the other (non-resonant) phases.
  We also show that, if multiplicity of the resonance equals one, generically
these tori occupy a set of large relative measure in the resonant domains in
the sense that the relative measure of the remaining "chaotic" set is of order
$\sqrt\varepsilon$. Therefore for small $\varepsilon > 0$ a random initial
condition in a $\sqrt\varepsilon$-neighborhood of a single resonance occurs
inside this set (and therefore generates a quasi-periodic motion) with a
probability much larger than in the "chaotic" set.
  We present results of numerical simulations and discuss the form of
projection of such tori to the action space.


title: 3+1 dimensional viscous hydrodynamics at high baryon densities

abstract:
  We apply a 3+1D viscous hydrodynamic + cascade model to the heavy ion
collision reactions with $\sqrt{s_{NN}}=6.3\dots39$ GeV. To accommodate the
model for a given collision energy range, the initial conditions for
hydrodynamic phase are taken from UrQMD, and the equation of state at finite
baryon density is based on Chiral model coupled to the Polyakov loop.
  We study the collision energy dependence of pion and kaon rapidity
distributions and $m_T$-spectra, as well as charged hadron elliptic flow and
how shear viscosity affects them. The model calculations are compared to the
data for Pb-Pb collisions at CERN SPS, as well as for Au-Au collisions in the
Beam Energy Scan (BES) program energies at BNL RHIC. The data favours the value
of shear viscosity $\eta/s\gtrsim0.2$ for this collision energy range.


title: The geometry of the moduli space of one-dimensional sheaves

abstract:
  Let $\mathbf{M}_d$ be the moduli space of stable sheaves on $\mathbb{P}^2$
with Hilbert polynomial $dm+1$. In this paper, we determine the effective and
the nef cone of the space $\mathbf{M}_d$ by natural geometric divisors. Main
idea is to use the wall-crossing on the space of Bridgeland stability
conditions and to compute the intersection numbers of divisors with curves by
using the Grothendieck-Riemann-Roch theorem. We also present the stable base
locus decomposition of the space $\mathbf{M}_6$. As a byproduct, we obtain the
Betti numbers of the moduli spaces, which confirm the prediction in physics.


title:
Two-particle correlations and balance functions in p-Pb and Pb-Pb
  collisions at LHC energies with ALICE

abstract:
  Recent measurements of two-particle correlations in high-multiplicity p-Pb
collisions at $\sqrt{s_{NN}} = 5.02$ TeV revealed a long-range structure (large
separation in $\Delta\eta$) at the near- ($\Delta\varphi\simeq0$) and away-side
($\Delta\varphi\simeq\pi$) of the trigger particle. At LHC energies, these
ridge-like structures have not only been observed in Pb-Pb collisions, but also
in high-multiplicity pp collisions. In the first case, this phenomenon is
commonly related to collectivity in hadron production, i.e. hydrodynamic
evolution, whereas in the latter, mechanisms like longitudinal color
connections and multi-parton interactions might play an important role. To shed
light on the particle production mechanisms in p-Pb and Pb-Pb collisions and
answer the question about collectivity, we extend the two-particle correlation
analysis for hadrons in two directions: identified particles, which should show
a characteristic pattern in case of collective motion in a hydrodynamic medium,
and charge-dependent correlations studied with the balance function, which are
sensitive to charge-dependent effects like local charge conservation.


title:
Numerical methods for parameter identification in stationary radiative
  transfer

abstract:
  We consider the identification of scattering and absorption rates in the
stationary radiative transfer equation. For a stable solution of this parameter
identification problem, we consider Tikhonov regularization within Banach
spaces. A regularized solution is then defined via an optimal control problem
constrained by an integro partial differential equation. By establishing the
weak-continuity of the parameter-to-solution map, we are able to ensure the
existence of minimizers and thus the well-posedness of the regularization
method. In addition, we prove certain differentiability properties, which allow
us to construct numerical algorithms for finding the minimizers and to analyze
their convergence. Numerical results are presented to support the theoretical
findings and illustrate the necessity of the assumptions made in the analysis.


title: Nearly Planar Graphs and {\lambda}-flat Graphs

abstract:
  A graph G is {\xi}-nearly planar if it can be embedded in the sphere so that
each of its edges is crossed at most {\xi} times. The family of {\xi}-nearly
planar graphs is widely extending the notion of planarity. We introduce an
alternative parameterized graph family extending the notion of planarity, the
{\lambda}-flat graphs, this time defined as powers of plane graphs in regard to
a novel notion of distance, the wall-by-wall distance. We show that the two
parameterized graph classes are parametrically equivalent.


title:
On the length of the shortest non-trivial element in the derived and the
  lower central series

abstract:
  We provide upper and lower bounds on the length of the shortest non-trivial
element in the derived series and lower central series in the free group on two
generators. The techniques are used to provide new estimates on the nilpotent
residual finiteness growth and on almost laws for compact groups.


title: Probing a dark matter density spike at the Galactic Center

abstract:
  The dark matter halo profile in the inner Galaxy is very uncertain. Yet its
radial dependence toward the Galactic Center is of crucial importance for the
determination of the gamma-ray and radio fluxes originating from dark matter
annihilations. Here we use synchrotron emission to probe the dark matter energy
distribution in the inner Galaxy. We first solve the problem of the cosmic ray
diffusion on very small scales, typically smaller than 10^{-3} pc, by using a
Green's function approach and use this technique to quantify the effect of a
spiky profile (rho(r) ~ r^{-7/3}) on the morphology and intensity of the
synchrotron emission expected from dark matter. We illustrate our results using
10 and 800 GeV candidate weakly interacting dark matter particles annihilating
directly into e+ e-. Our most critical assumptions are that the dark matter is
heavier than a few GeV and directly produces a reasonable amount of electrons
and positrons in the Galaxy. We conclude that dark matter indirect detection
techniques (including the Planck experiment) could be used to shed light on the
dark matter halo profile on scales that lie beyond the capability of any
current numerical simulations.


title: Exponential Splines of Complex Order

abstract:
  We extend the concept of exponential B-spline to complex orders. This
extension contains as special cases the class of exponential splines and also
the class of polynomial B-splines of complex order. We derive a time domain
representation of a complex exponential B-spline depending on a single
parameter and establish a connection to fractional differential operators
defined on Lizorkin spaces. Moreover, we prove that complex exponential splines
give rise to multiresolution analyses of $L^2(\mathbb{R})$ and define wavelet
bases for $L^2(\mathbb{R})$.


title:
New Li-Ethylenediamine-Intercalated Superconductor
  Li$_x$(C$_2$H$_8$N$_2$)$_y$Fe$_{2-z}$Se$_2$ with $T_c$ = 45 K

abstract:
  A new iron-based superconductor Li$_x$(C$_2$H$_8$N$_2$)$_y$Fe$_{2-z}$Se$_2$
with $T_c$ = 45 K has successfully been synthesized via intercalation of
dissolved lithium metal in ethylenediamine. The distance between neighboring Fe
layers is 10.37 {\AA} and much larger than those of FeSe with $T_c$ = 8 K and
K$_x$Fe$_2$Se$_2$ with $T_c$ ~ 30 K. It seems that the high-$T_c$ of
Li$_x$(C$_2$H$_8$N$_2$)$_y$Fe$_{2-z}$Se$_2$ is caused by the possible
two-dimensional electronic structure due to the large $c$-axis length.


title:
Topological genericity of nowhere differentiable functions in the disc
  algebra

abstract:
  In this paper we introduce a class of functions contained in the disc algebra
$\mathcal{A}(D)$. We study functions $f \in \mathcal{A}(D)$, which have the
property that the continuous periodic function $u = Ref|_{\mathbb{T}}$, where
$\mathbb{T}$ is the unit circle, is nowhere differentiable. We prove that this
class is non-empty and instead, generically, every function $f \in
\mathcal{A}(D)$ has the above property. Afterwards, we strengthen this result
by proving that, generically, for every function $f \in \mathcal{A}(D)$, both
continuous periodic functions $u=Ref|_\mathbb{T}$ and $\tilde{u} =
Imf|_\mathbb{T}$ are nowhere differentiable. We avoid any use of the
Weierstrass function and we mainly use Baire's Category Theorem.


title: Exact Methods for Self Interacting Neutrinos

abstract:
  The effective many-body Hamiltonian which describes vacuum oscillations and
self interactions of neutrinos in a two flavor mixing scheme under the single
angle approximation has the same dynamical symmetries as the well known BCS
pairing Hamiltonian. These dynamical symmetries manifest themselves in terms of
a set of constants of motion and can be useful in formulating the collective
oscillation modes in an intuitive way. In particular, we show that a neutrino
spectral split can be simply viewed as an avoided level crossing between the
eigenstates of a mean field Hamiltonian which includes a Lagrange multiplier in
order to fix the value of an exact many-body constant of motion. We show that
the same dynamical symmetries also exist in the three neutrino mixing scheme by
explicitly writing down the corresponding constants of motion.


title: Some Notes on the Rapanui Archaeoastronomy

abstract:
  This paper is dedicated to the research of secrets of Easter Island (Rapa
Nui), a remote plot of land in the Pacific; the work includes not only
necessary ethnological data, but also some results on the archaeoastronomy. The
analysis of several rock drawings lets us date them. The priests Hina Mango and
Rahu (Rahi) were not only experts on the script, but also great astronomers.
There is abundant evidence that the priests-astronomers used the astrolabe in
their studies. The local astronomical terminology has been decoded. The
observatory at the ceremonial platform Ahu Tongariki has been investigated
carefully. The orientation of a female statue on the slope of the Rano Raraku
volcano allows us to suggest that it was an image of the Moon (the moon
goddess). A number of additional astronomical and calendar records in the rock
art and in the writing have been deciphered.


title:
Lattice dynamics and electronic structure of energetic solids LiN3 and
  NaN3: A first principles study

abstract:
  We report density functional theory calculations on the crystal structure,
elastic, lattice dynamics and electronic properties of iso-structural layered
monoclinic alkali azides, LiN3 and NaN3. The effect of van der Waals
interactions on the ground- state structural properties is studied by using
various dispersion corrected density functionals. Based on the equilibrium
crystal structure, the elastic constants, phonon dispersion and phonon density
of states of the compounds are calculated. The accurate energy band gaps are
obtained by using the recently developed Tran Blaha-modified Becke Johnson
(TB-mBJ) functional and found that both the azides are direct band gap
insulators.


title:
A comparison of the new exact solutions of the relativistic wave
  equations of a charged particle propagating in a strong laser field in an
  underdense plasma

abstract:
  The relativistic wave equations of a charged particle propagating in a
classical monochromatic electromagnetic plane wave, in a medium of index of
refraction n_m < 1, have been studied. In the Dirac case the found exact
solutions [arXiv:1305.4370] are expressed in terms of new complex polynomials,
and in the Klein-Gordon case they are expressed in term of Ince polynomials
[arXiv:1306.0097]. In each case these solutions form a doubly infinite discrete
set, parametrized by quantized momentum components of the charged particle
along the polarization vector and along the propagation direction of the
electromagnetic radiation (which may be considered as a plasmon wave of
arbitrary high amplitude, propagating in an underdense plasma). These solutions
describe a high-contrast periodic structure of the particle density on the
plasma length scale, and they may have relevance in the study of novel
acceleration mechanisms.


title:
On the Source of the Dust Extinction in Type Ia Supernovae and the
  Discovery of Anomalously Strong Na I Absorption

abstract:
  High-dispersion observations of the Na I D 5890, 5896 and K I 7665, 7699
interstellar lines, and the diffuse interstellar band at 5780 Angstroms in the
spectra of 32 Type Ia supernovae are used as an independent means of probing
dust extinction. We show that the dust extinction of the objects where the
diffuse interstellar band at 5780 Angstroms is detected is consistent with the
visual extinction derived from the supernova colors. This strongly suggests
that the dust producing the extinction is predominantly located in the
interstellar medium of the host galaxies and not in circumstellar material
associated with the progenitor system. One quarter of the supernovae display
anomalously large Na I column densities in comparison to the amount of dust
extinction derived from their colors. Remarkably, all of the cases of unusually
strong Na I D absorption correspond to "Blueshifted" profiles in the
classification scheme of Sternberg et al. (2011). This coincidence suggests
that outflowing circumstellar gas is responsible for at least some of the cases
of anomalously large Na I column densities. Two supernovae with unusually
strong Na I D absorption showed essentially normal K I column densities for the
dust extinction implied by their colors, but this does not appear to be a
universal characteristic. Overall, we find the most accurate predictor of
individual supernova extinction to be the equivalent width of the diffuse
interstellar band at 5780 Angstroms, and provide an empirical relation for its
use. Finally, we identify ways of producing significant enhancements of the Na
abundance of circumstellar material in both the single-degenerate and
double-degenerate scenarios for the progenitor system.


title:
Charged jet spectra in proton-proton collisions with the ALICE
  experiment at the LHC

abstract:
  Jets are collimated sprays of particles resulting from fragmentation of hard
scattered partons. They are measured in different types of collisions at
different energies to test perturbative Quantum Chromodynamic calculations and
are used to study the hard scattering, fragmentation and hadronisation of
partons. These phenomena, measured in simple systems such as proton--proton
collisions, serve as a baseline to investigate their modifications by hot and
dense nuclear matter created in high energy heavy-ion collisions.
  We have analysed data from minimum bias proton--proton collisions at centre
of mass energy of 2.76 and 7 TeV collected using the ALICE detector system at
the LHC and reconstructed the inclusive jet cross section from charged tracks
at midrapidity. We present jet spectra reconstructed using the infrared and
colinear safe anti-kT algorithm with underlying event subtraction, corrected
for detector effects via unfolding for both collision energies. Furthermore,
results from analyses of fragmentation distributions and jet shape observables
are shown. All results are compared with measurements of other LHC experiments
and with Monte Carlo generators.


title: Vacuum alignment and phase structure of holographic bi-layers

abstract:
  We study the D3/probe D5 system with two domain wall hypermultiplets. The
conformal symmetry can be broken by a magnetic field, B, (or running coupling)
which promotes condensation of the fermions on each individual domain wall.
Separation of the domain walls promotes condensation of the fermions between
one wall and the other. We study the competition between these two effects
showing a first order phase transition when the separation is ~ 0.56 lambda^1/4
B^-1/2. We identify extremal brane configurations which exhibit both
condensations simultaneously but they are not the preferred ground state.


title:
Exact criterion for global existence and blow up to a degenerate
  Keller-Segel system

abstract:
  A degenerate Keller-Segel system with diffusion exponent
$2n/(n+2)<m<2-\frac{2}{n}$ in multi dimension is studied. An exact criterion
for global existence and blow up of solution is obtained. The estimates on
$L^{2n/(n+2)}$ norm of the solution play important roles in our analysis. These
estimates are closely related to the optimal constant in Haddy- Littlewood-
Sobolev inequality. In the case of initial free energy less than a universal
constant which depends on the inverse of total mass, there exists a constant
such that if the $L^{2n/(n+2)}$ norm of initial data is less than this
constant, then the weak solution exists globally; if the $L^{2n/(n+2)}$ norm of
initial data is larger than the same constant, then the solution must blow-up
in finite time. Our result shows that the total mass, which plays the
deterministic role in two dimension case, might not be an appropriate criterion
for existence and blow up discussion in multi-dimension, while the
$L^{\frac{2n}{n+2}}$ norm of the initial data and the relation between initial
free energy and initial mass are more important.


title:
A Study On ID-based Authentication Schemes for Telecare Medical
  Information System

abstract:
  The smart card based authentication schemes are designed and developed to
ensure secure and authorized communication between remote user and the server.
In recent times, many smart card based authentication schemes for the telecare
medical information systems (TMIS) have been presented. In this article, we
briefly discuss some of the recently published smart card based authentication
schemes for TMIS and try to show why efficient login and password change phases
are required. In other word, the study demonstrates how inefficient password
change phase leads to denial of server attack and how inefficient login phase
increase the communication and computation overhead and decrease the
performance of the system.


title: Supersymmetric KdV equation: Darboux transformation and discrete systems

abstract:
  For the supersymmetric KdV equation, a proper Darboux transformation is
presented. This Darboux transformation leads to the B\"{a}cklund transformation
found early by Liu and Xie \cite{liu2}. The Darboux transformation and the
related B\"{a}cklund transformation are used to construct integrable super
differential-difference and difference-difference systems. The continuum limits
of these discrete systems and of their Lax pairs are also considered.


title: Higher-order Sobolev embeddings and isoperimetric inequalities

abstract:
  Optimal higher-order Sobolev type embeddings are shown to follow via
isoperimetric inequalities. This establishes a higher-order analogue of a
well-known link between first-order Sobolev embeddings and isoperimetric
inequalities. Sobolev type inequalities of any order, involving arbitrary
rearrangement-invariant norms, on open sets in $\rn$, possibly endowed with a
measure density, are reduced to much simpler one-dimensional inequalities for
suitable integral operators depending on the isoperimetric function of the
relevant sets.
  As a consequence, the optimal target space in the relevant Sobolev embeddings
can be determined both in standard and in non-standard classes of function
spaces and underlying measure spaces. In particular, our results are applied to
any-order Sobolev embeddings in regular (John) domains of the Euclidean space,
in Maz'ya classes of (possibly irregular) Euclidean domains described in terms
of their isoperimetric function, and in families of product probability spaces,
of which the Gauss space is a classical instance.


title:
Mean-Field Limit for a Collision-Avoiding Flocking System and the
  Time-Asymptotic Flocking Dynamics for the Kinetic Equation

abstract:
  A Collision-Avoiding flocking particle system proposed in [8] is studied in
this paper. The global wellposedness of its corresponding Vlasov-type kinetic
equation is proved. As a corollary of the global stability result, the mean
field limit of the particle system is obtained. Furthermore, the
time-asymptotic flocking behavior of the solution to the kinetic equation is
also derived. The technics used for local wellposedness and stability follow
from similar ideas to those have been used in [3,22,14]. While in order to
extend the local result globally, the main contribution here is to generate a
series of new estimates for this Vlasov type equation, which imply that the
growing of the characteristics can be controlled globally. Further estimates
also show the long time flocking phenomena.


title: Compactness of higher-order Sobolev embeddings

abstract:
  We study higher-order compact Sobolev embeddings on a domain $\Omega
\subseteq \mathbb R^n$ endowed with a probability measure $\nu$ and satisfying
certain isoperimetric inequality. Given $m\in \mathbb N$, we present a
condition on a pair of rearrangement-invariant spaces $X(\Omega,\nu)$ and
$Y(\Omega,\nu)$ which suffices to guarantee a compact embedding of the Sobolev
space $V^mX(\Omega,\nu)$ into $Y(\Omega,\nu)$. The condition is given in terms
of compactness of certain one-dimensional operator depending on the
isoperimetric function of $(\Omega,\nu)$. We then apply this result to the
characterization of higher-order compact Sobolev embeddings on concrete measure
spaces, including John domains, Maz'ya classes of Euclidean domains and product
probability spaces, whose standard example is the Gauss space.


title:
$L_{1/2}$ Regularization: Convergence of Iterative Half Thresholding
  Algorithm

abstract:
  In recent studies on sparse modeling, the nonconvex regularization approaches
(particularly, $L_{q}$ regularization with $q\in(0,1)$) have been demonstrated
to possess capability of gaining much benefit in sparsity-inducing and
efficiency. As compared with the convex regularization approaches (say, $L_{1}$
regularization), however, the convergence issue of the corresponding algorithms
are more difficult to tackle. In this paper, we deal with this difficult issue
for a specific but typical nonconvex regularization scheme, the $L_{1/2}$
regularization, which has been successfully used to many applications. More
specifically, we study the convergence of the iterative \textit{half}
thresholding algorithm (the \textit{half} algorithm for short), one of the most
efficient and important algorithms for solution to the $L_{1/2}$
regularization. As the main result, we show that under certain conditions, the
\textit{half} algorithm converges to a local minimizer of the $L_{1/2}$
regularization, with an eventually linear convergence rate. The established
result provides a theoretical guarantee for a wide range of applications of the
\textit{half} algorithm. We provide also a set of simulations to support the
correctness of theoretical assertions and compare the time efficiency of the
\textit{half} algorithm with other known typical algorithms for $L_{1/2}$
regularization like the iteratively reweighted least squares (IRLS) algorithm
and the iteratively reweighted $l_{1}$ minimization (IRL1) algorithm.


title:
Spectra and elliptic flow for identified hadrons in 2.76 A TeV Pb+Pb
  collisions

abstract:
  Using the VISHNU hybrid model that couples (2+1)-dimensional viscous
hydrodynamics to a microscopic hadronic transport model, we calculate the
multiplicity, p_T spectra and elliptic flow for pions, kaons, and protons in
2.76 A TeV Pb+Pb collisions, using MC-KLN initializations with smoothed initial
conditions, obtained by averaging over a large number of events. The results
from our calculations are compared to data from the ALICE collaboration,
showing nice agreement over several centrality bins. Using the same inputs, we
predict the p_T spectra and elliptic flow for phi mesons and explore its flow
development in the strong and weak coupling limits through hydrodynamic
calculations with different decoupling temperatures. In addition we study the
influence of baryon and anti-baryon annihilation processes on common
observables and demonstrate that by including annihilation processes below a
switching temperature of 165 MeV, VISHNU provides a good description of the
multiplicity and p_T spectra for pions, kaons and protons measured by PHENIX
and ALICE at both RHIC and the LHC.


title:
Plasmons in metallic monolayer and bilayer transition metal
  dichalcogenides

abstract:
  We study the collective electronic excitations in metallic single- and
bilayer transition metal dichalcogenides (TMDCs) using time dependent density
functional theory in the random phase approximation. For very small momentum
transfers (below $q\approx0.02$~\AA$^{-1}$) the plasmon dispersion follows the
$\sqrt{q}$ behavior expected for free electrons in two dimensions. For larger
momentum transfer the plasmon energy is significantly red shifted due to
screening by interband transitions. At around $q\approx 0.1$ \AA$^{-1}$ the
plasmon enters the dissipative electron-hole continuum and the plasmon
dispersions flatten out at an energy around 0.6-1.1 eV, depending on the
material. Using bilayer NbSe$_2$ as example, we show that the plasmon modes of
a bilayer structure take the form of symmetric and anti-symmetric hybrids of
the single-layer modes. The spatially anti-symmetric mode is rather weak with a
linear dispersion tending to zero for $q=0$ while the energy of the symmetric
mode follows the single-layer mode dispersion with a slight blue shift.


title: A new view on spin reduced density matrix for relativistic particles

abstract:
  We present a new interpretation for reduced density matrices of secondary
variables in relativistic systems via an analysis of Wigner's method to
construct the irreducible unitary representations of the Poincar\'e group. We
argue that the usual partial trace method used to obtain spin reduced matrices
is not fully rigorous, however, employing our interpretation, similar effective
reduced density matrices can be constructed. In addition, we show that our
proposal is more useful than the usual one since we are not restricted only to
the reduced density matrices that could be obtained by the ordinary partial
trace method.


title: Higher moments for random multiplicative measures

abstract:
  We obtain a condition for the $L^q$-convergence of martingales generated by
random multiplicative cascade measures for $q>1$ without any self-similarity
requirements on the cascades.


title:
Effect of Se doping in recently discovered layered Bi4O4S3
  Superconductor

abstract:
  We report suppression of superconductivity in Bi4O4S3 compound by Se doping
at S site. Bulk polycrystalline samples are synthesized by solid state reaction
route. The Rietveld refined of XRD data of all the studied samples show that
the same are crystallized in tetragonal I4/mmm space group with slightly
increased c lattice constant with the Se doping. Superconductivity is observed
at below 4.5 K in both dc magnetization and resistivity with temperature
measurements for all Bi4O4S3-xSex (x = 0, 0.03, 0.09 and 0.15) samples, though
the same is decreased slightly with increase in Se content. The upper critical
field of the Bi4O4S3 is estimated from resistivity under magnetic field [R(T)H]
measurements of up to 2T (Tesla), and the same decreases for Se doped samples.
The flux flow activation energies being obtained by fitting to the the
Arrhenius equation are 18.60 meV for Bi4O4S3, 13.69 meV for Bi4O4S2.97Se0.03
and 13.16 meV for Bi4O4S2.85Se0.15 samples in applied magnetic field of 200 Oe.
In conclusion the S site Se substitution showed detrimental effect on
superconductivity of Bi4O4S3.


title: Iterative Bilateral Filtering of Polarimetric SAR Data

abstract:
  In this paper, we introduce an iterative speckle filtering method for
polarimetric SAR (PolSAR) images based on the bilateral filter. To locally
adapt to the spatial structure of images, this filter relies on pixel
similarities in both spatial and radiometric domains. To deal with polarimetric
data, we study the use of similarities based on a statistical distance called
Kullback-Leibler divergence as well as two geodesic distances on Riemannian
manifolds. To cope with speckle, we propose to progressively refine the result
thanks to an iterative scheme. Experiments are run over synthetic and
experimental data. First, simulations are generated to study the effects of
filtering parameters in terms of polarimetric reconstruction error, edge
preservation and smoothing of homogeneous areas. Comparison with other methods
shows that our approach compares well to other state of the art methods in the
extraction of polarimetric information and shows superior performance for edge
restoration and noise smoothing. The filter is then applied to experimental
data sets from ESAR and FSAR sensors (DLR) at L-band and S-band, respectively.
These last experiments show the ability of the filter to restore structures
such as buildings and roads and to preserve boundaries between regions while
achieving a high amount of smoothing in homogeneous areas.


title:
Dynamical Image Charge Effect in Molecular Tunnel Junctions: Beyond
  Energy Level Alignment

abstract:
  When an electron tunnels between two metal contacts it temporarily induces an
image charge (IC) in the electrodes which acts back on the tunneling electron.
It is usually assumed that the IC forms instantaneously such that a static
model for the image potential applies. Here we investigate how the finite IC
formation time affects charge transport through a molecule suspended between
two electrodes. For a single level model, an analytical treatment shows that
the conductance is suppressed by a factor $Z^2$ (compared to the static IC
approximation) where $Z$ is the quasiparticle renormalization factor. We show
that $Z$ can be expressed either in terms of the plasma frequency of the
electrode or as the overlap between the ground states of the electrode with and
without an electron on the molecule. First-principles GW calculations for
benzene-diamine connected to gold electrodes show that the dynamical
corrections can reduce the conductance by more than a factor of two.


title:
Emergence of small-world anatomical networks in self-organizing
  clustered neuronal cultures

abstract:
  In vitro primary cultures of dissociated invertebrate neurons from locust
ganglia are used to experimentally investigate the morphological evolution of
assemblies of living neurons, as they self-organize from collections of
separated cells into elaborated, clustered, networks. At all the different
stages of the culture's development, identification of neurons' and neurites'
location by means of a dedicated software allows to ultimately extract an
adjacency matrix from each image of the culture. In turn, a systematic
statistical analysis of a group of topological observables grants us the
possibility of quantifying and tracking the progression of the main network's
characteristics during the self-organization process of the culture. Our
results point to the existence of a particular state corresponding to a
small-world network configuration, in which several relevant graph's micro- and
meso-scale properties emerge. Finally, we identify the main physical processes
ruling the culture's morphological transformations, and embed them into a
simplified growth model qualitatively reproducing the overall set of
experimental observations.


title: Nonlinear Optical Probe of Indirect Excitons

abstract:
  We propose the application of nonlinear optics for studies of spatially
indirect excitons in coupled quantum wells. We demonstrate, that despite their
vanishing oscillator strength, indirect excitons can strongly contribute to the
photoinduced reflectivity and Kerr rotation. This phenomenon is governed by the
interaction between direct and indirect excitons. Both dark and bright states
of indirect excitons can be probed by these nonlinear optical techniques.


title:
Constraining the spin-down timescale of the white-dwarf progenitors of
  Type Ia supernovae

abstract:
  Justham (2011) and DiStefano et al.\ (2011) proposed that the white-dwarf
progenitor of a Type Ia supernova (SN Ia) may have to spin down before it can
explode. As the white dwarf spin-down timescale is not well known
theoretically, we here try to constrain it empirically (within the framework of
this spin-down model) for progenitor systems that contain a giant donor and for
which circumbinary material has been detected after the explosion: we obtain an
upper limit of a few $10^{\rm 7} {\rm yr}$. Based on the study of Di Stefano &
Kilic (2012) this means that it is too early to rule out the existence of a
surviving companion in SNR 0509-67.5.


title:
Andreev spectroscopy of CrO$_{2}$ thin films on TiO$_{2}$ and
  Al$_{2}$O$_{3}$

abstract:
  Here we analyse the spectroscopic information gathered at a number of single
CrO$_{2}$ / Pb interfaces. We examine thin films requiring additional
interfacial layers to generate long range spin triplet proximity effect
superconductivity (CrO$_{2}$/TiO$_{2}$) or not (CrO$_{2}$/Al$_{2}$O$_{3}$). We
analyse the data using two theoretical models and explore the use of a
parameter free method to determine the agreement between the models and
experimental observations, showing the necessary temperature range that would
be required to make a definitive statement. The use of the excess current as a
further tool to distinguish between models is also examined. Analysis of the
spectra demonstrates that the temperature dependence of the normalised zero
bias conductance is independent of the substrate onto which the films are
grown. This result has important implications for the engineering of interfaces
required for the long range spin triplet proximity effect.


title: Neutron skin of $^{208}$Pb from Coherent Pion Photoproduction

abstract:
  Information on the size and shape of the neutron skin on $^{208}$Pb has been
extracted from coherent pion photoproduction cross sections measured using the
Crystal Ball together with the Glasgow tagger at the MAMI electron beam
facility. On exploitation of an interpolated fit of a theoretical model to the
measured cross sections the half-height radius and diffuseness of the neutron
distribution are found to be 6.70$\pm 0.03(stat)$ fm and 0.55$\pm
0.01(stat)$$^{+0.02}_{-0.03}(sys)$ fm respectively, corresponding to a neutron
skin thickness $\Delta r_{np}$=0.15$\pm 0.03(stat)$$^{+0.01}_{-0.03}(sys)$ fm.
The results give the first successful extraction of a neutron skin with an
electromagnetic probe and indicate the skin of $^{208}$Pb has a halo character.
The measurement provides valuable new constraints on both the structure of
nuclei and the equation of state for neutron-rich matter.


title:
Pushing the limits of the eigenstate thermalization hypothesis towards
  mesoscopic quantum systems

abstract:
  In the ongoing discussion on thermalization in closed quantum many-body
systems, the eigenstate thermalization hypothesis (ETH) has recently been
proposed as a universal concept which attracted considerable attention. So far
this concept is, as the name states, hypothetical. The majority of attempts to
overcome this hypothetical character is based on exact diagonalization which
implies for, e.g., spin systems a limitation to roughly 15 spins. In this
Letter we present an approach which pushes this limit up to system sizes of
roughly 35 spins, thereby going significantly beyond what is possible with
exact diagonalization. A concrete application to a Heisenberg spin-ladder which
yields conclusive results is demonstrated.


title: A Technique for Efficiently Managing SRAM-NVM Hybrid Cache

abstract:
  In this paper, we present a SRAM-PCM hybrid cache design, along with a cache
replacement policy, named dead fast block (DFB) to manage the hybrid cache.
This design aims to leverage the best features of both SRAM and PCM devices.
Compared to a PCM-only cache, the hybrid cache with DFB policy provides
superior results on all relevant evaluation metrics, viz. cache lifetime,
performance and energy efficiency. Also, use of DFB policy for managing the
hybrid cache provides better results compared to LRU replacement policy on all
the evaluation metrics.


title:
Chemical Property of Colliding Sources in 124,136Xe and 112,124Sn
  Induced Collisions in Isobaric Ratio Difference and Isoscaling Methods

abstract:
  The isoscaling and isobaric ratio difference (IBD) methods are used to study
the $\Delta\mu/T$ ($\Delta\mu$ being the difference between the chemical
potentials of neutron and proton, and $T$ being the temperature) in the
measured 1$A$ GeV $^{124}$Sn + $^{124}$Sn, $^{112}$Sn + $^{112}$Sn, $^{136}$Xe
+ Pb and $^{124}$Xe + Pb reactions. The isoscaling phenomena in the
$^{124}$Sn/$^{112}$Sn and the $^{136}$Xe/$^{124}$Xe reactions pairs are
investigated, and the isoscaling parameter $\alpha$ and $\beta$ are obtained.
The $\Delta\mu/T$ determined by the isoscaling method (IS--$\Delta\mu/T$) and
IBD method (IB--$\Delta\mu/T$) in the measured Sn and Xe reactions are
compared. It is shown that in most of fragments, the IS-- and IB--
$\Delta\mu/T$ are consistent in the Xe reactions, while the IS-- and IB--
$\Delta\mu/T$ are only similar in the less neutron-rich fragments in the Sn
reactions. The shell effects in IB--$\Delta\mu/T$ are also discussed.


title: The PFR Conjecture Holds for Two Opposing Special Cases

abstract:
  Let $A \subseteq F_2^n$ be a set with $|2A| = K|A|$. We prove that if (1) for
at least a fraction $1-K^{-9}$ of all $s \in 2A$, the set $(A+s) \cap A$ has
size at most $L\cdot|A|/K$, or (2) for at least a fraction $K^{-L}$ of all $s
\in 2A$, the set $(A+s) \cap A$ has size at least $|A|\cdot(1- K^{-1/L})$, then
there is a subset $B \subseteq A$ of size $|A|/K^{O_L(1)}$ such that
$\mathrm{span}(B) \leq K^{O_L(1)}\cdot|A|$.


title:
An alternative proof of a PTAS for fixed-degree polynomial optimization
  over the simplex

abstract:
  The problem of minimizing a polynomial over the standard simplex is one of
the basic NP-hard nonlinear optimization problems --- it contains the maximum
clique problem in graphs as a special case. It is known that the problem allows
a polynomial-time approximation scheme (PTAS) for polynomials of fixed degree,
which is based on polynomial evaluations at the points of a sequence of regular
grids. In this paper, we provide an alternative proof of the PTAS property. The
proof relies on the properties of Bernstein approximation on the simplex. We
also refine a known error bound for the scheme for polynomials of degree three.
The main contribution of the paper is to provide new insight into the PTAS by
establishing precise links with Bernstein approximation and the multinomial
distribution.


title: Spectral Functions for Regular Sturm-Liouville Problems

abstract:
  In this paper we provide a detailed analysis of the analytic continuation of
the spectral zeta function associated with one-dimensional regular
Sturm-Liouville problems endowed with self-adjoint separated and coupled
boundary conditions. The spectral zeta function is represented in terms of a
complex integral and the analytic continuation in the entire complex plane is
achieved by using the Liouville-Green (or WKB) asymptotic expansion of the
eigenfunctions associated with the problem. The analytically continued
expression of the spectral zeta function is then used to compute the functional
determinant of the Sturm-Liouville operator and the coefficients of the
asymptotic expansion of the associated heat kernel.


title: Euler systems for modular forms over imaginary quadratic fields

abstract:
  We construct an Euler system attached to a weight 2 modular form twisted by a
Groessencharacter of an imaginary quadratic field, and apply this to bounding
Selmer groups.


title: Slow foliation of a slow-fast stochastic evolutionary system

abstract:
  This work is concerned with the dynamics of a slow-fast stochastic
evolutionary system quantified with a scale parameter. An invariant foliation
decomposes the state space into geometric regions of different dynamical
regimes, and thus helps understand dynamics. A slow invariant foliation is
established for this system. It is shown that the slow foliation converges to a
critical foliation (i.e., the scale parameter is zero) in probability
distribution, as the scale parameter tends to zero. The approximation of slow
foliation is also constructed with error estimate in distribution. Furthermore,
the geometric structure of the slow foliation is investigated: every fiber of
the slow foliation parallels each other, with the slow manifold as a special
fiber. In fact, when an arbitrarily chosen point of a fiber falls in the slow
manifold, the fiber must be the slow manifold itself.


title: Consistency relation in power law G-inflation

abstract:
  In the standard inflationary scenario based on a minimally coupled scalar
field, canonical or non-canonical, the subluminal propagation of speed of
scalar perturbations ensures the following consistency relation: $r \leq -
8n_{_T}$, where $r$ is the tensor-to-scalar-ratio and $n_{_T}$ is the spectral
index for tensor perturbations. However, recently, it has been demonstrated
that this consistency relation could be violated in Galilean inflation models
even in the absence of superluminal propagation of scalar perturbations. It is
therefore interesting to investigate whether the subluminal propagation of
scalar field perturbations impose any bound on the ratio $r/|n_{_T}|$ in
G-inflation models. In this paper, we derive the consistency relation for a
class of G-inflation models that lead to power law inflation. Within these
class of models, it turns out that one can have $r > - 8n_{_T}$ or $r \leq -
8n_{_T}$ depending on the model parameters. However, the subluminal propagation
of speed of scalar field perturbations, as required by causality, restricts $r
\leq -(32/3)\,n_{_T}$.


title: Recurrence of bipartite planar maps

abstract:
  This paper concerns random bipartite planar maps which are defined by
assigning weights to their faces. The paper presents a threefold contribution
to the theory. Firstly, we prove the existence of the local limit for all
choices of weights and describe it in terms of an infinite mobile. Secondly, we
show that the local limit is in all cases almost surely recurrent. And thirdly,
we show that for certain choices of weights the local limit has exactly one
face of infinite degree and has in that case spectral dimension $4/3$ (the
latter requires a mild moment condition).


title:
Inhomogeneous phases in one-dimensional mass- and spin-imbalanced Fermi
  gases

abstract:
  We compute the phase diagram of strongly interacting fermions in one
dimension at finite temperature, with mass and spin imbalance. By including the
possibility of the existence of a spatially inhomogeneous ground state, we find
regions where spatially varying superfluid phases are favored over homogeneous
phases. We obtain estimates for critical values of the temperature, mass and
spin imbalance, above which these phases disappear. Finally, we show that an
intriguing relation exists between the general structure of the phase diagram
and the binding energies of the underlying two-body bound-state problem.

categories: cond-mat.quant-gas cond-mat.other hep-ph nucl-th


title:
Superconducting complementary metasurfaces for THz ultrastrong
  light-matter coupling

abstract:
  A superconducting metasurface operating in the THz range and based on the
complementary metamaterial approach is discussed. Experimental measurements as
a function of temperature and magnetic field display a modulation of the
metasurface with a change in transmission amplitude and frequency of the
resonant features. Such a metasurface is successively used as a resonator for a
cavity quantum electrodynamic experiment displaying ultrastrong coupling to the
cyclotron transition of a 2DEG. A finite element modeling is developed and its
results are in good agreement with the experimental data. In this system a
normalized coupling ratio of $\frac{\Omega}{\omega_c}=0.27$ is measured and a
clear modulation of the polaritonic states as a function of the temperature is
observed.


title:
The Log-Volume of Optimal Codes for Memoryless Channels, Asymptotically
  Within A Few Nats

abstract:
  Shannon's analysis of the fundamental capacity limits for memoryless
communication channels has been refined over time. In this paper, the maximum
volume $M_\avg^*(n,\epsilon)$ of length-$n$ codes subject to an average
decoding error probability $\epsilon$ is shown to satisfy the following tight
asymptotic lower and upper bounds as $n \to \infty$: \[ \underline{A}_\epsilon
+ o(1) \le \log M_\avg^*(n,\epsilon) - [nC - \sqrt{nV_\epsilon}
\,Q^{-1}(\epsilon) + \frac{1}{2} \log n] \le \overline{A}_\epsilon + o(1) \]
where $C$ is the Shannon capacity, $V_\epsilon$ the $\epsilon$-channel
dispersion, or second-order coding rate, $Q$ the tail probability of the normal
distribution, and the constants $\underline{A}_\epsilon$ and
$\overline{A}_\epsilon$ are explicitly identified. This expression holds under
mild regularity assumptions on the channel, including nonsingularity. The gap
$\overline{A}_\epsilon - \underline{A}_\epsilon$ is one nat for weakly
symmetric channels in the Cover-Thomas sense, and typically a few nats for
other symmetric channels, for the binary symmetric channel, and for the $Z$
channel. The derivation is based on strong large-deviations analysis and
refined central limit asymptotics. A random coding scheme that achieves the
lower bound is presented. The codewords are drawn from a capacity-achieving
input distribution modified by an $O(1/\sqrt{n})$ correction term.


title:
The effect of recombination radiation on the temperature and ionization
  state of partially ionized gas

abstract:
  A substantial fraction of all ionizing photons originate from radiative
recombinations. However, in radiative transfer calculations this recombination
radiation is often assumed to be absorbed 'on-the-spot' because for most
methods the computational cost associated with the inclusion of gas elements as
sources is prohibitive. We present a new, CPU and memory efficient
implementation for the transport of ionizing recombination radiation in the
TRAPHIC radiative transfer scheme. TRAPHIC solves the radiative transfer
equation by tracing photon packets at the speed of light and in a
photon-conserving manner in spatially adaptive smoothed particle hydrodynamics
simulations. Our new implementation uses existing features of the TRAPHIC
scheme to add recombination radiation at no additional cost in the limit in
which the fraction of the simulation box filled with radiation approaches 1. We
test the implementation by simulating an HII region in photoionization
equilibrium and comparing to reference solutions presented in the literature,
finding excellent agreement. We apply our implementation to discuss the
evolution of the HII region to equilibrium. We show that the widely used case A
and B approximations yield accurate ionization profiles only near the source
and near the ionization front, respectively. We also discuss the impact of
recombination radiation on the geometry of shadows behind optically thick
absorbers. We demonstrate that the shadow region may be completely ionized by
the diffuse recombination radiation field and discuss the important role of
heating by recombination radiation in the shadow region.


title: Left-right twin Higgs model confronted with the latest LHC Higgs data

abstract:
  Motivated by the latest LHC Higgs data, we calculate the new physics
contributions to the Higgs decay channels of $h\to \gamma\gamma, Z\gamma,
\tau\tau, WW^*$ and $ ZZ^*$ in the left-right twin Higgs (LRTH) model, induced
by the loops involving the heavy T-quark, the $W_H$ and $\phi^\pm$ bosons
appeared in the LRTH model. We find that (a) for a SM-like Higgs boson around
125.5 GeV, the signal rates normalized to the corresponding standard model (SM)
predictions are always suppressed when new physics contributions are taken into
account and approach the SM predictions for a large scalar parameter $f$; and
(b) the LRTH prediction for $R_{\gamma\gamma}$ agree well with the CMS
measurement $R_{\gamma\gamma}=0.77\pm 0.27$ at $1\sigma$ level, but differ with
the ATLAS result. The forthcoming precision measurement of the diphoton signal
at the LHC can be a sensitive probe for the LRTH model.


title: Spectroscopy of Masses and Couplings during Inflation

abstract:
  In this work, we extend the idea of Quasi Single Field inflation to the case
of multiple isocurvaton fields with masses of order of Hubble, which are
coupled kinetically to the inflaton field and have some interactions among
themselves. We consider the effects of these massive modes in both the size and
the shape of the bispectrum. We show that the shape of the bispectrum in the
squeezed limit is dominated by the lightest field and is the same as in Quasi
Single Field inflation. This is a generic feature of multiple isocurvaton
fields and is independent of the details of the interactions among the massive
fields. When the isocurvaton fields have similar masses, we can potentially
distinguish two different shapes in the squeezed limit so that the shape of the
bispectrum can act as a particle detector. However, in the presence of
hierarchy among the massive fields, the dominant effect is due to the lightest
field.


title:
On a question of Hof, Knill and Simon on palindromic substitutive
  systems

abstract:
  In a 1995 paper, Hof, Knill and Simon obtain a sufficient combinatorial
criterion on the hull $\Omega$ of the potential of a discrete Schr\"odinger
operator which guarantees purely singular continuous spectrum on a generic
subset of $\Omega.$ In part, this condition requires the existence of
infinitely many palindromic factors. In this same paper, they introduce the
class P of morphisms $f:A^*\rightarrow B^*$ of the form $a\mapsto pq_a$ and ask
whether every palindromic subshift generated by a primitive substitution arises
from morphisms of class P or by morphisms of the form $a\mapsto q_ap$ where
again $p$ and $q_a$ are palindromes. In this paper we give a partial
affirmative answer to the question of Hof, Knill and Simon: we show that every
rich primitive substitutive subshift is generated by at most two morphisms each
of which is conjugate to a morphism of class P. More precisely, we show that
every rich (or almost rich in the sense of finite defect) primitive morphic
word $y\in B^\omega$ is of the form $y=f(x)$ where $f:A^*\rightarrow B^*$ is
conjugate to a morphism of class P, and where $x$ is a rich word fixed by a
primitive substitution $g:A^*\rightarrow A^*$ of class P.


title: Twistor relative locality

abstract:
  We present a version of relative locality based on the geometry of twistor
space. This can also be thought of as a new kind of deformation of twistor
theory based on the construction of a bundle of twistor spaces over momentum
space. Locality in space-time is emergent and is deformed in a precise way when
a connection on that bundle is non-flat. This gives a precise and controlled
meaning to Penrose's hypothesis that quantum gravity effects will deform
twistor space in such a way as to maintain causality and relativistic
invariance while weakening the notion that interactions take place at points in
spacetime.


title: The Gromov-Eliashberg theorem by microlocal sheaf theory

abstract:
  The Gromov-Eliashberg theorem says that the group of symplectomorphisms of a
symplectic manifold is C^0-closed in the group of diffeomorphisms. This can be
translated into a statement about the Lagrangian submanifolds which are graphs
of symplectomorphisms. It is also known that such Lagrangian submanifolds are
locally microsupports of sheaves. We explain how we can deduce the
Gromov-Eliashberg theorem from the involutivity theorem of Kashiwara and
Schapira which says that the microsupport of a sheaf is coisotropic.


title:
Polynomial solutions for a class of second-order linear differential
  equations

abstract:
  We analyze the polynomial solutions of the linear differential equation
$p_2(x)y''+p_1(x)y'+p_0(x)y=0$ where $p_j(x)$ is a $j^{\rm th}$-degree
polynomial. We discuss all the possible polynomial solutions and their
dependence on the parameters of the polynomials $p_j(x)$. Special cases are
related to known differential equations of mathematical physics. Classes of new
soluble problems are exhibited. General results are obtained for weight
functions and orthogonality relations.


title:
A Hermite pseudospectral solver for two-dimensional incompressible flows
  on infinite domains

abstract:
  The Hermite pseudospectral method is applied to solve the Navier-Stokes
equations on a two-dimensional infinite domain. The feature of Hermite function
allows us to adopt larger time steps than other spectral methods, but also
leads to some extra computation when the stream-function is calculated from the
vorticity field. The scaling factor is employed to increase the resolution
within the region of our main interest, and the aliasing error is fully removed
by the 2/3-$rule$. Several traditional numerical experiments are performed with
high accuracy, and some related future work on physical applications of this
program is also discussed.


title: On the typical properties of inverse problems in statistical mechanics

abstract:
  In this work we consider the problem of extracting a set of interaction
parameters from an high-dimensional dataset describing T independent
configurations of a complex system composed of N binary units. This problem is
formulated in the language of statistical mechanics as the problem of finding a
family of couplings compatible with a corresponding set of empirical
observables in the limit of large N. We focus on the typical properties of its
solutions and highlight the possible spurious features which are associated
with this regime (model condensation, degenerate representations of data,
criticality of the inferred model). We present a class of models (complete
models) for which the analytical solution of this inverse problem can be
obtained, allowing us to characterize in this context the notion of stability
and locality. We clarify the geometric interpretation of some of those aspects
by using results of differential geometry, which provides means to quantify
consistency, stability and criticality in the inverse problem. In order to
provide simple illustrative examples of these concepts we finally apply these
ideas to datasets describing two stochastic processes (simulated realizations
of a Hawkes point-process and a set of time-series describing financial
transactions in a real market).


title: Describe the Fibonacci map by principal nests

abstract:
  In this paper,we studied some properties of the Fibonacci map and find a
property of this map related to the notation of principal nest. And weproved
this property with some additional conditions equals the original definition of
Fibonacci map. Therefore give us a new method to describe Fibonacci map.


title: Sobolev spaces on graded groups

abstract:
  We study the Lp-properties of positive Rockland operators and define Sobolev
spaces on general graded groups. This generalises the case of sub-Laplacians on
stratified groups studied by G. Folland in [3]. We show that the defined
Sobolev spaces are actually independent of the choice of a positive Rockland
operator. Furthermore, we show that they are interpolation spaces and establish
duality and Sobolev embedding theorems in this context.


title: Kinetic theory of acoustic-like modes in nonextensive pair plasmas

abstract:
  The low-frequency acoustic-like modes in a pair plasma (electron-positron or
pair-ion) is studied by employing a kinetic theory model based on the Vlasov
and Poisson's equation with emphasizing the Tsallis's nonextensive statistics.
The possibility of the acoustic-like modes and their properties in both fully
symmetric and temperature-asymmetric cases are examined by studying the
dispersion relation, Landau damping and instability of modes. The resultant
dispersion relation in this study is compatible with the acoustic branch of the
experimental data [W. Oohara, D. Date, and R. Hatakeyama, Phys. Rev. Lett. 95,
175003 (2005)], in which the electrostatic waves have been examined in a pure
pair-ion plasma. Particularly, our study reveals that the occurrence of growing
or damped acoustic-like modes depends strongly on the nonextensivity of the
system as a measure for describing the long-range Coulombic interactions and
correlations in the plasma. The mechanism that leads to the unstable modes lies
in the heart of the nonextensive formalism yet, the mechanism of damping is the
same developed by Landau. Furthermore, the solutions of acoustic-like waves in
an equilibrium Maxwellian pair plasma are recovered in the extensive limit
($q\rightarrow1$), where the acoustic modes have only the Landau damping and no
growth.


title: Typical martingale diverges at a typical point

abstract:
  We investigate convergence of martingales adapted to a given filtration of
finite $\sigma$-algebras. To any such filtration we associate a canonical
metrizable compact space $K$ such that martingales adapted to the filtration
can be canonically represented on $K$. We further show that (except for trivial
cases) typical martingale diverges at a comeager subset of $K$. `Typical
martingale' means a martingale from a comeager set in any of the standard
spaces of martingales. In particular we show that a typical $L^1$-bounded
martingale of norm at most one converges almost surely to zero and has maximal
possible oscillation on a comeager set.


title: On the Listsize Capacity with Feedback

abstract:
  The listsize capacity of a discrete memoryless channel is the largest
transmission rate for which the expectation---or, more generally, the $\rho$-th
moment---of the number of messages that could have produced the output of the
channel approaches one as the blocklength tends to infinity. We show that for
channels with feedback this rate is upper-bounded by the maximum of Gallager's
$E_0$ function divided by $\rho$, and that equality holds when the zero-error
capacity of the channel is positive. To establish this inequality we prove that
feedback does not increase the cutoff rate. Relationships to other notions of
channel capacity are explored.


title: Goals for teacher learning about energy degradation and usefulness

abstract:
  The Next Generation Science Standards (NGSS) require teachers to understand
aspects of energy degradation and the second law of thermodynamics, including
energy's availability and usefulness, changes in energy concentration, and the
tendency of energy to spread uniformly. In an effort to develop learning goals
that support teachers in building robust understandings of energy from their
existing knowledge, we studied teachers' impromptu conversations about these
topics during professional development courses about energy. Many of these
teachers' ideas appear to align with statements from the NGSS, including the
intuition that energy can be present but inaccessible, that energy can change
in its usefulness as it transforms within a system, and that energy can lose
its usefulness as it disperses, often ending up as thermal energy. Some
teachers' ideas about energy degradation go beyond what is articulated in the
NGSS, including the idea that thermal energy can be useful in some situations
and the idea that energy's usefulness depends on the objects included in a
scenario. Based on these observations, we introduce learning goals for energy
degradation and the second law of thermodynamics that (1) represent a
sophisticated physics understanding of these concepts, (2) originate in ideas
that teachers already use, and (3) align with the NGSS.


title:
Measurement of the Target-Normal Single-Spin Asymmetry in Deep-Inelastic
  Scattering from the Reaction $^{3}\mathrm{He}^{\uparrow}(e,e')X$

abstract:
  We report the first measurement of the target-normal single-spin asymmetry in
deep-inelastic scattering from the inclusive reaction
$^3$He$^{\uparrow}\left(e,e' \right)X$ on a polarized $^3$He gas target.
Assuming time-reversal invariance, this asymmetry is strictly zero in the Born
approximation but can be non-zero if two-photon-exchange contributions are
included. The experiment, conducted at Jefferson Lab using a 5.89 GeV electron
beam, covers a range of $1.7 < W < 2.9$ GeV, $1.0<Q^2<4.0$ GeV$^2$ and
$0.16<x<0.65$. Neutron asymmetries were extracted using the effective nucleon
polarization and measured proton-to-$^3$He cross section ratios. The measured
neutron asymmetries are negative with an average value of $(-1.09 \pm 0.38)
\times10^{-2}$ for invariant mass $W>2$ GeV, which is non-zero at the
$2.89\sigma$ level. Our measured asymmetry agrees both in sign and magnitude
with a two-photon-exchange model prediction that uses input from the Sivers
transverse momentum distribution obtained from semi-inclusive deep-inelastic
scattering.


title: Decomposing Truthful and Competitive Online Double Auctions

abstract:
  In this paper, we study online double auctions, where multiple sellers and
multiple buyers arrive and depart dynamically to exchange one commodity. We
show that there is no deterministic online double auction that is truthful and
competitive for maximising social welfare in an adversarial model. However,
given the prior information that sellers are patient and the demand is not more
than the supply, a deterministic and truthful greedy mechanism is actually
2-competitive, i.e. it guarantees that the social welfare of its allocation is
at least half of the optimal one achievable offline. Moreover, if the number of
incoming buyers is predictable, we demonstrate that an online double auction
can be reduced to an online one-sided auction, and the truthfulness and
competitiveness of the reduced online double auction follow that of the online
one-sided auction. Notably, by using the reduction, we find a truthful
mechanism that is almost 1-competitive, when buyers arrive randomly. Finally,
we argue that these mechanisms also have a promising applicability in more
general settings without assuming that sellers are patient, by decomposing a
market into multiple sub-markets.


title: On the Lie group structure of pseudo-Finsler isometries

abstract:
  Using an extension to isometries of the associated Sasaki structure, we
establish a Lie transformation group structure for the set of isometries of a
pseudo-Finsler conical metric.


title: Quasi-Invariance under Flows Generated by Non-Linear PDEs

abstract:
  The paper is concerned with the change of probability measures $\mu$ along
non-random probability measure valued trajectories $\nu_t$, $t\in [-1,1]$.
Typically solutions to non-linear PDEs, modeling spatial development as time
progresses, generate such trajectories. Depending on in which direction the map
$\nu\equiv\nu_0\mapsto\nu_t$ does not exit the state space, for $t\in [-1,0]$
or for $t\in [0,1]$, quasi-invariance of the measure $\mu$ under the map
$\nu\mapsto\nu_t$ is established and the Radon-Nikodym derivative of
$\mu\circ\nu_t$ with respect to $\mu$ is determined. It is also investigated
how Fr\'echet differentiability of the solution map of the PDE can contribute
to the existence of this Radon-Nikodym derivative. The first application is a
certain Boltzmann type equation. Here the Fr\'echet derivative of the solution
map is calculated explicitly and quasi-invariance is established. The second
application is a PDE related to the asymptotic behavior of a Fleming-Viot type
particle system. Here quasi-invariance is obtained and it is demonstrated how
this result can be used in order to derive a corresponding integration by parts
formula.


title:
Exploring atmospheres of hot mini-Neptunes and extrasolar giant planets
  orbiting different stars with application to HD 97658b, WASP-12b, CoRoT-2b,
  XO-1b and HD 189733b

abstract:
  We calculated an atmospheric grid for hot mini-Neptune and giant exoplanets,
that links astrophysical observable parameters- orbital distance and stellar
type- with the chemical atmospheric species expected. The grid can be applied
to current and future observations to characterize exoplanet atmospheres and
serves as a reference to interpret atmospheric retrieval analysis results. To
build the grid, we developed a 1D code for calculating the atmospheric thermal
structure and link it to a photochemical model that includes disequilibrium
chemistry (molecular diffusion, vertical mixing and photochemistry). We compare
thermal profiles and atmospheric composition of planets at different semimajor
axis (0.01$\leq$a$\leq$0.1AU) orbiting F, G, K and M stars. Temperature and UV
flux affect chemical species in the atmosphere. We explore which effects are
due to temperature and which due to stellar characteristics, showing the
species most affected in each case. CH$_4$ and H$_2$O are the most sensitive to
UV flux, H displaces H$_2$ as the most abundant gas in the upper atmosphere for
planets receiving a high UV flux. CH$_4$ is more abundant for cooler planets.
We explore vertical mixing, to inform degeneracies on our models and in the
resulting spectral observables. For lower pressures observable species like
H$_2$O or CO$_2$ can indicate the efficiency of vertical mixing, with larger
mixing ratios for a stronger mixing. By establishing the grid, testing the
sensitivity of the results and comparing our model to published results, our
paper provides a tool to estimate what observations could yield. We apply our
model to WASP-12b, CoRoT-2b, XO-1b, HD189733b and HD97658b.


title: A systematic comparison of supervised classifiers

abstract:
  Pattern recognition techniques have been employed in a myriad of industrial,
medical, commercial and academic applications. To tackle such a diversity of
data, many techniques have been devised. However, despite the long tradition of
pattern recognition research, there is no technique that yields the best
classification in all scenarios. Therefore, the consideration of as many as
possible techniques presents itself as an fundamental practice in applications
aiming at high accuracy. Typical works comparing methods either emphasize the
performance of a given algorithm in validation tests or systematically compare
various algorithms, assuming that the practical use of these methods is done by
experts. In many occasions, however, researchers have to deal with their
practical classification tasks without an in-depth knowledge about the
underlying mechanisms behind parameters. Actually, the adequate choice of
classifiers and parameters alike in such practical circumstances constitutes a
long-standing problem and is the subject of the current paper. We carried out a
study on the performance of nine well-known classifiers implemented by the Weka
framework and compared the dependence of the accuracy with their configuration
parameter configurations. The analysis of performance with default parameters
revealed that the k-nearest neighbors method exceeds by a large margin the
other methods when high dimensional datasets are considered. When other
configuration of parameters were allowed, we found that it is possible to
improve the quality of SVM in more than 20% even if parameters are set
randomly. Taken together, the investigation conducted in this paper suggests
that, apart from the SVM implementation, Weka's default configuration of
parameters provides an performance close the one achieved with the optimal
configuration.


title: SDC13 infrared dark clouds: Longitudinally collapsing filaments?

abstract:
  Formation of stars is now believed to be tightly linked to the dynamical
evolution of interstellar filaments in which they form. In this paper we
analyze the density structure and kinematics of a small network of infrared
dark filaments, SDC13, observed in both dust continuum and molecular line
emission with the IRAM 30m telescope. These observations reveal the presence of
18 compact sources amongst which the two most massive, MM1 and MM2, are located
at the intersection point of the parsec-long filaments. The dense gas velocity
and velocity dispersion observed along these filaments show smooth, strongly
correlated, gradients. We discuss the origin of the SDC13 velocity field in the
context of filament longitudinal collapse. We show that the collapse timescale
of the SDC13 filaments (from 1 Myr to 4 Myr depending on the model parameters)
is consistent with the presence of Class I sources in them, and argue that, on
top of bringing more material to the centre of the system, collapse could
generate additional kinematic support against local fragmentation, helping the
formation of starless super-Jeans cores.


title:
Mosco Type Convergence and Weak Convergence for a Fleming-Viot type
  Particle System

abstract:
  We are concerned with Mosco type convergence for a non-symmetric $n$-particle
Fleming-Viot system $\{X_1,\ldots,X_n\}$ in a bounded $d$-dimensional domain
$D$ with smooth boundary. Moreover, we are interested in relative compactness
of the $n$-particle processes. It turns out that integration by parts relative
to the initial measure and the generator is the appropriate mathematical tool.
For finitely many particles, such integration by parts is established by using
probabilistic arguments. For the limiting infinite dimensional configuration we
use a result from infinite dimensional non-gaussian calculus.


title:
Quantum field theory solves the problem of the collapse of the wave
  function

abstract:
  The problem of measurement in quantum mechanics is that the quantum particle
in the course of evolution, as described by the linear Schrodinger equation,
exists in all of its possible states, but in measuring, the particle is always
detected in only one of its states. This property is called the "collapse of
the wave function" and was formulated by Von Neumann as one of the postulates
of quantum mechanics. However, it remains unclear at what point in time and
under what laws this transition occurs. This article demonstrates that the
collapse of the wave function may be due to the creation or annihilation of
particles (quasi-particles). The processes of the creation or annihilation of
particles play a key role in the measurements and are described on the basis of
quantum field theory. The system of equations of quantum field theory of
particles and fields is non-linear; as a result, the principle of superposition
does not hold for the theory. The collapse of the wave function is a
consequence of this non-linearity and occurs at the moment of creation
(annihilation) of a particle. This result demonstrates that the wave function
collapse can occur in both microscopic and macroscopic systems. Understanding
the mechanisms of the collapse of the wave function can lead to the creation of
microscopic devices involved in the calculations based on quantum computing.


title:
Newtonian, Post Newtonian and Parameterized Post Newtonian limits of
  f(R, G) gravity

abstract:
  We discuss in detail the weak field limit of f(R,G) gravity taking into
account analytic functions of the Ricci scalar R and the Gauss-Bonnet invariant
G. Specifically, we develop, in metric formalism, the Newtonian, Post Newtonian
and Parameterized Post Newtonian limits starting from general f(R, G)
Lagrangian. The special cases of f(R) and f(G) gravities are considered. In the
case of the Newtonian limit of f(R, G) gravity, a general solution in terms of
Green's functions is achieved.


title: Kwee-van Woerden method: To use or not to use?

abstract:
  The trustworthiness of orbital period analyses of eclipsing binaries strictly
depends on the correctness of the observed mid-eclipse time determination, as
well the reliability of its uncertainty estimation. The majority of them has
been determined by means of the Kwee-van Woerden method (KWM). There are also
other possibilities: to use physical models of eclipsing binaries or light
curve templates and to determine mid-eclipse times using the least square
method (LSM). We compared results yielded by both methods by means of a
computer simulation on the synthetic model of AR\,Aur primary minimum. Minima
times determined by the KWM and the exact LSM approach are nearly the same,
while the scatter of LSM times is always smaller than the scatter of KWM times.
KWM uncertainties are systematically underestimated. We think that the time is
ripe for the Kwee-van Woerden method to retire.


title: Stein fillings of planar open books

abstract:
  We prove that if a contact manifold $(M,\xi)$ is supported by a planar open
book, then Euler characteristic and signature of any Stein filling of $(M,\xi)$
is bounded. We also prove a similar finiteness result for contact manifolds
supported by spinal open books with planar pages. Moving beyond the geography
of Stein fillings, we classify fillings of some lens spaces.


title: Anderson localization of light with topological dislocations

abstract:
  We predict Anderson localization of light with nested screw topological
dislocations propagating in disordered two-dimensional arrays of hollow
waveguides illuminated by vortex beams. The phenomenon manifests itself in the
statistical presence of topological dislocations in ensemble-averaged output
distributions accompanying standard disorder-induced localization of light
spots. Remarkably, screw dislocations are captured by the light spots despite
the fast and irregular transverse displacements and topological charge flipping
undertaken by the dislocations due to the disorder. The statistical averaged
modulus of the output local topological charge depends on the initial vorticity
carried by the beam.


title:
Quantum discord for two-qubit $X$-states: A comprehensive approach
  inspired by classical polarization optics

abstract:
  Classical correlation and quantum discord are computed for two-qubit
$X$-states. Our approach, which is inspired by the methods of classical
polarization optics, is geometric in the sense that the entire analysis is tied
to the correlation ellipsoid of all normalized conditional states of the
A-qubit with measurement elements applied to the B-qubit. Aspects of the
computation which depend on the location of the reduced state of A inside the
ellipsoid get clearly separated from those which do not. Our treatment is
comprehensive\,: all known results are reproduced, often more economically, and
several new insights and results emerge. Detailed reexamination of the famous
work of Ali, Rau, and Alber [Phys. Rev. A {\bf 81}, 042105 (2010)], in the
light of ours and a counterexample we manufacture against their principal
theorem points to an uncommon situation in respect of their principal result\,:
their theorem turns out to be `numerically correct' in all but a very tiny
region in the space of $X$-states, notwithstanding the fact that their proof of
the theorem seems to make, in the disguise of an unusual group theoretic
argument, an {\em a priori} assumption equivalent to the theorem itself.


title: Hunter & Mole

abstract:
  We consider a variation of a cops and robbers game in which the cop---here
referred to as "hunter"---is not constrained by the graph but must play in the
dark against a "mole." We characterize the graphs---which we will call
"hunter-win"---on which the hunter can guarantee capture of the mole in bounded
time. We also define an optimal hunter strategy (and consequently an upper
bound on maximum game time on hunter-win graphs) and note that an optimal
hunter strategy need not take advantage of the hunter's unconstrained movement!
This game comes from a puzzle of unknown origin which was told to the authors
by Dick Hess.


title:
Baseline optimization for the measurement of CP violation, mass
  hierarchy, and $\theta_{23}$ octant in a long-baseline neutrino oscillation
  experiment

abstract:
  Next-generation long-baseline electron neutrino appearance experiments will
seek to discover CP violation, determine the mass hierarchy and resolve the
$\theta_{23}$ octant. In light of the recent precision measurements of
$\theta_{13}$, we consider the sensitivity of these measurements in a study to
determine the optimal baseline, including practical considerations regarding
beam and detector performance. We conclude that a detector at a baseline of at
least 1000 km in a wide-band muon neutrino beam is the optimal configuration.


title:
Polynomial entropy for the circle homeomorphisms and for $C^1$
  nonvanishing vector fields on $\T^2$

abstract:
  We prove that the polynomial entropy of an orientation preserving
homeomorphism of the circle equals 1 when the homeomorphism is not conjugate to
a rotation and that it is 0 otherwise. In a second part we prove that the
polynomial entropy of a flow on the two dimensional torus associated with a
$C^1$ nonvanishing vector field is less that $1$. We moreover prove that when
the flow possesses periodic orbits its polynomial entropy equals 1 unless it is
conjugate to a rotation (in this last case, the polynomial entropy is zero).


title:
Centrality, rapidity and transverse momentum dependence of $J/\psi$
  suppression in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$=2.76 TeV

abstract:
  The inclusive $J/\psi$ nuclear modification factor $R_{\rm AA}$ in Pb-Pb
collisions at $\sqrt{s_{\rm NN}}$=2.76 TeV has been measured by ALICE as a
function of centrality in the e$^+$e$^-$ decay channel at mid-rapidity
$|y|<0.8$ and as a function of centrality, transverse momentum and rapidity in
the $\mu^{+}\mu^{-}$ decay channel at forward-rapidity $2.5<y<4$.The $J/\psi$
yields measured in Pb-Pb are suppressed compared to those in pp collisions
scaled by the number of binary collisions. The $R_{\rm AA}$ integrated over a
centrality range corresponding to 90% of the inelastic Pb-Pb cross section is
$0.72\pm0.06$ (stat.) $\pm0.10$ (syst.) at mid-rapidity and $0.57 \pm 0.01$
(stat.) $\pm0.09$ (syst.) at forward-rapidity. At low transverse momentum,
significantly larger values of $R_{\rm AA}$ are measured at forward-rapidity
compared to measurements at lower energy. These features suggest that a
contribution to the $J/\psi$ yield originates from charm quarks (re)combination
in the deconfined partonic medium.


title:
Development of Parallel Plate Avalanche Counter PPAC for BigRIPS
  fragment separator

abstract:
  We have developed a position-sensitive Parallel Plate Avalanche Counter
(PPAC), which has been used as a focal plane detector in the BigRIPS fragment
separator and the subsequent RI-beam delivery lines at the RIKEN Nishina Center
RI Beam Factory. The PPAC detector plays an important role not only in the
tuning of the separator and delivery lines but also in the particle
identification of rare isotope (RI) beams. The PPAC detector has a sensitive
area of 240 mm x 150 mm, and the position information is obtained by a
delay-line readout method. Being called double PPAC, it is composed of two full
PPACs, each measuring the particle locus in two dimensions. High detection
efficiency has been made possible by the twofold measurement using the double
PPAC detector. The sensitivity uniformity is also found to be excellent. The
root-mean-square position resolution is measured to be 0.25 mm using an alpha
source, while the position linearity is as good as +/-0.1 mm for the detector
size of 240 mm. Characteristics, operating principles, specifications,
performance and issues of the PPAC detector are presented, including its signal
transmission system using optical fiber cables.


title: Searching a Dark Photon with HADES

abstract:
  We present a search for the e+e- decay of a hypothetical dark photon, also
names U vector boson, in inclusive dielectron spectra measured by HADES in the
p (3.5 GeV) + p, Nb reactions, as well as the Ar (1.756 GeV/u) + KCl reaction.
An upper limit on the kinetic mixing parameter squared epsilon^{2} at 90% CL
has been obtained for the mass range M(U) = 0.02 - 0.55 GeV/c2 and is compared
with the present world data set. For masses 0.03 - 0.1 GeV/c^2, the limit has
been lowered with respect to previous results, allowing now to exclude a large
part of the parameter region favoured by the muon g-2 anomaly. Furthermore, an
improved upper limit on the branching ratio of 2.3 * 10^{-6} has been set on
the helicity-suppressed direct decay of the eta meson, eta-> e+e-, at 90% CL.


title: Universal Axial Algebras and a Theorem of Sakuma

abstract:
  In the first half of this paper, we define axial algebras: nonassociative
commutative algebras generated by axes, that is, semisimple idempotents---the
prototypical example of which is Griess' algebra [C85] for the Monster group.
When multiplication of eigenspaces of axes is controlled by fusion rules, the
structure of the axial algebra is determined to a large degree. We give a
construction of the universal Frobenius axial algebra on $n$ generators with a
specified fusion rules, of which all $n$-generated Frobenius axial algebras
with the same fusion rules are quotients. In the second half, we realise this
construction in the Majorana / Ising / $\mathrm{Vir}(4,3)$-case on $2$
generators, and deduce a result generalising Sakuma's theorem in VOAs [S07].


title:
Analysis of topological structure of the QCD vacuum with overlap-Dirac
  operator eigenmode

abstract:
  Using the eigenmodes of the overlap-Dirac operator, we study the topological
structure of the QCD vacuum. We investigate the space-time profile of the
low-lying eigenmodes and their contribution to the vacuum action density and
chiral condensate under the existence of static color sources. We demonstrate
that the low-lying Dirac eigenmode shows the flux-tube structure, which
suggests the relevance to confinement. We also analyze the chiral condensate in
the flux-tube. Chiral symmetry is partially restored inside the flux, and the
reduction of the condensate is about 20% at the center of the tube.


title:
Joint Estimation of Multiple Graphical Models from High Dimensional Time
  Series

abstract:
  In this manuscript we consider the problem of jointly estimating multiple
graphical models in high dimensions. We assume that the data are collected from
n subjects, each of which consists of T possibly dependent observations. The
graphical models of subjects vary, but are assumed to change smoothly
corresponding to a measure of closeness between subjects. We propose a kernel
based method for jointly estimating all graphical models. Theoretically, under
a double asymptotic framework, where both (T,n) and the dimension d can
increase, we provide the explicit rate of convergence in parameter estimation.
It characterizes the strength one can borrow across different individuals and
impact of data dependence on parameter estimation. Empirically, experiments on
both synthetic and real resting state functional magnetic resonance imaging
(rs-fMRI) data illustrate the effectiveness of the proposed method.


title:
Kaluza-Klein multidimensional models with Ricci-flat internal spaces:
  the absence of the KK particles

abstract:
  In this paper we consider a multidimensional Kaluza-Klein (KK) model with a
Ricci-flat internal space, e.g., a Calabi-Yau manifold. We perturb this
background metrics by a system of gravitating masses, e.g., astrophysical
objects such as our Sun. We suppose that these masses are pressureless in the
external space but they have relativistic pressure in the internal space. We
show that metric perturbations do not depend on coordinates of the internal
space and gravitating masses should be uniformly smeared over the internal
space. This means, first, that KK modes corresponding to the metric
fluctuations are absent and, second, particles should be only in the ground
quantum state with respect to the internal space. In our opinion, these results
look very unnatural. According to statistical physics, any nonzero temperature
should result in fluctuations, i.e. in KK modes. We also get formulae for the
metric correction terms which enable to calculate the gravitational tests: the
deflection of light, the time-delay of the radar echoes and the perihelion
advance.


title: Guided modes in a spatially dispersive wire medium slab

abstract:
  We study the guided modes in the wire medium slab taking into account both
the nonlocality and losses in the structure. We show that due to the fact that
the wire medium is an extremeley spatially dispersive metamaterial, the effect
of nonlocality plays a critical role since it results in coupling between the
otherwise orthogonal guided modes. We observe both the effects of strong and
weak coupling, depending on the level of losses in the system.


title: Online Learning with Multiple Operator-valued Kernels

abstract:
  We consider the problem of learning a vector-valued function f in an online
learning setting. The function f is assumed to lie in a reproducing Hilbert
space of operator-valued kernels. We describe two online algorithms for
learning f while taking into account the output structure. A first contribution
is an algorithm, ONORMA, that extends the standard kernel-based online learning
algorithm NORMA from scalar-valued to operator-valued setting. We report a
cumulative error bound that holds both for classification and regression. We
then define a second algorithm, MONORMA, which addresses the limitation of
pre-defining the output structure in ONORMA by learning sequentially a linear
combination of operator-valued kernels. Our experiments show that the proposed
algorithms achieve good performance results with low computational cost.


title:
Exploring the X-ray and gamma-ray properties of the redback millisecond
  pulsar PSR J1723-2837

abstract:
  We have investigated the X-ray and $\gamma$-ray properties of the redback
millisecond pulsar PSR J1723-2837 with XMM-Newton, Chandra and Fermi. We have
discovered the X-ray orbital modulation of this binary system with the minimum
that coincides with the phases of radio eclipse. The X-ray emission is clearly
non-thermal in nature which can be well described by a simple power-law with a
photon index of $\sim1.2$. The phase-averaged luminosity is
$\sim9\times10^{31}$ erg/s in 0.3-10 keV which consumes $\sim0.2\%$ of the
spin-down power. We have detected the $\gamma-$ray emission in $0.1-300$ GeV
from this system at a significance of $\sim6\sigma$ for the first time. The
$\gamma-$rays in this energy range consumes $\sim2\%$ of the spin-down power
and can be modeled by a power-law with a photon index of $\sim2.6$. We discuss
the high energy properties of the new redback in the context of a intrabinary
shock model.


title:
Faster Algorithms For Vertex Partitioning Problems Parameterized by
  Clique-width

abstract:
  Many NP-hard problems, such as Dominating Set, are FPT parameterized by
clique-width. For graphs of clique-width $k$ given with a $k$-expression,
Dominating Set can be solved in $4^k n^{O(1)}$ time. However, no FPT algorithm
is known for computing an optimal $k$-expression. For a graph of clique-width
$k$, if we rely on known algorithms to compute a $(2^{3k}-1)$-expression via
rank-width and then solving Dominating Set using the $(2^{3k}-1)$-expression,
the above algorithm will only give a runtime of $4^{2^{3k}} n^{O(1)}$. There
have been results which overcome this exponential jump; the best known
algorithm can solve Dominating Set in time $2^{O(k^2)} n^{O(1)}$ by avoiding
constructing a $k$-expression [Bui-Xuan, Telle, and Vatshelle. Fast dynamic
programming for locally checkable vertex subset and vertex partitioning
problems. Theoret. Comput. Sci., 2013. doi:10.1016/j.tcs.2013.01.009]. We
improve this to $2^{O(k\log k)}n^{O(1)}$. Indeed, we show that for a graph of
clique-width $k$, a large class of domination and partitioning problems
(LC-VSP), including Dominating Set, can be solved in $2^{O(k\log{k})}
n^{O(1)}$. Our main tool is a variant of rank-width using the rank of a $0$-$1$
matrix over the rational field instead of the binary field.


title: Emergent Symmetry on Black Hole Horizons

abstract:
  For a stationary and axisymmetric black hole, there is a natural way to split
the fields into a probe sector and a background sector. The equations of motion
for the probe sector enjoy a significantly enhanced symmetry on the black hole
horizon. The extended symmetry is conformal in four dimensions, while in higher
dimensions it is much bigger. This puts conformal symmetry at the bottom of the
ladder of symmetries that can arise on black hole horizons in generic
dimensions.