title:
Radial distribution of the diffuse gamma-ray emissivity in the galactic
  disk

abstract:
  The Fermi-LAT data accumulated over 7 years of {\gamma}-ray observations,
together with the high resolution gas (CO & HI) and the dust opacity maps, are
used to study the emissivity of {\gamma}-rays induced by interactions of cosmic
rays (CRs) with the interstellar medium. Based on the dust opacity templates,
the {\gamma}-ray emissivity was measured for 36 segments of the Galactic plane.
Furthermore, the {\gamma}-ray emissivity was evaluated in six Galactocentric
rings. Both the absolute emissivity and the energy spectra of {\gamma}-rays
derived in the interval 0.2-100 GeV show significant variations along the
galactic plane. The density of CRs, derived under the assumption that
{\gamma}-rays are predominately produced in CR interactions with the
interstellar gas, is characterised by a strong radial dependence. In the inner
Galaxy the CR density substantially exceeds the density in the outer parts of
the Galaxy: by a factor of a few at 10 GeV, and by more than an order of
magnitude at 1 TeV. Remarkably, the energy distribution of CRs appears to be
substantially harder than the energy spectrum obtained from direct measurements
of local CRs. At the same time, the flux and the energy spectrum of multi-GeV
protons derived from {\gamma}-ray data in the outskirts of the Galaxy is quite
close to the measurements of local CRs.


title: Half-Skyrmion Spin Textures In Polariton Microcavities

abstract:
  We study the polarization dynamics of a spatially expanding polariton
condensate under nonresonant linearly polarized optical excitation. The
spatially and temporally resolved polariton emission reveals the formation of
non-trivial spin textures in the form of a quadruplet polarization pattern both
in the linear and circular Stokes parameters, and an octuplet in the diagonal
Stokes parameter. The continuous rotation of the polariton pseudospin vector
through the condensate due to TE-TM splitting exhibits an ordered pattern of
half-skyrmions associated with a half-integer topological number. A theoretical
model based on a driven-dissipative Gross-Pitaevskii equation coupled with an
exciton reservoir describes the dynamics of the nontrivial spin textures
through the optical spin-Hall effect.


title:
A review on locomotion robophysics: the study of movement at the
  intersection of robotics, soft matter and dynamical systems

abstract:
  In this review we argue for the creation of a physics of moving systems -- a
locomotion "robophysics" -- which we define as the pursuit of the discovery of
principles of self generated motion. Robophysics can provide an important
intellectual complement to the discipline of robotics, largely the domain of
researchers from engineering and computer science. The essential idea is that
we must complement study of complex robots in complex situations with
systematic study of simplified robophysical devices in controlled laboratory
settings and simplified theoretical models. We must thus use the methods of
physics to examine successful and failed locomotion in simplified (abstracted)
devices using parameter space exploration, systematic control, and techniques
from dynamical systems. Using examples from our and other's research, we will
discuss how such robophysical studies have begun to aid engineers in the
creation of devices that begin to achieve life-like locomotor abilities on and
within complex environments, have inspired interesting physics questions in low
dimensional dynamical systems, geometric mechanics and soft matter physics, and
have been useful to develop models for biological locomotion in complex
terrain. The rapidly decreasing cost of constructing sophisticated robot models
with easy access to significant computational power bodes well for scientists
and engineers to engage in a discipline which can readily integrate experiment,
theory and computation.

categories: cs.RO cond-mat.soft nlin.AO physics.bio-ph


title: Modeling of technological performance trends using design theory

abstract:
  Functional technical performance usually follows an exponential dependence on
time but the rate of change (the exponent) varies greatly among technological
domains. This paper presents a simple model that provides an explanatory
foundation for these phenomena based upon the inventive design process.
  The model assumes that invention - novel and useful design- arises through
probabilistic analogical transfers that combine existing knowledge by combining
existing individual operational ideas to arrive at new individual operating
ideas. The continuing production of individual operating ideas relies upon
injection of new basic individual operating ideas that occurs through coupling
of science and technology simulations.
  The individual operational ideas that result from this process are then
modeled as being assimilated in components of artifacts characteristic of a
technological domain. According to the model, two effects (differences in
interactions among components for different domains and differences in scaling
laws for different domains) account for the differences found in improvement
rates among domains whereas the analogical transfer process is the source of
the exponential behavior. The model is supported by a number of known empirical
facts: further empirical research is suggested to independently assess further
predictions made by the model.


title:
Masses of doubly charmed baryons in the extended on-mass-shell
  renormalization scheme

abstract:
  In this work, we investigate the mass corrections of the doubly charmed
baryons up to $N^2LO$ in the extended-on-mass-shell (EOMS) renormalization
scheme, comparing with the results of heavy baryon chiral perturbation theory.
We find that the terms from the heavy baryon approach are a subset of those
obtained in the EOMS scheme. By fitting the lattice data, we can determine the
parameters $\tilde{m}$, $\alpha$, $c_1$ and $c_7$ from the Lagrangian, while in
the heavy baryon approach no information on $c_1$ can be obtained from the
baryons mass. Correspondingly, the masses of $m_{\Xi_{cc}}$ and
$m_{\Omega_{cc}}$ are predicted, in the EOMS scheme, extrapolating the results
from different values of the charm quark and the pion masses of the lattice QCD
calculations.


title:
Prospects of eLISA for Detecting Galactic Binary Black Holes Similar to
  GW150914

abstract:
  We discuss the prospects of eLISA for detecting gravitational waves (GWs)
from Galactic binary black holes (BBHs) similar to GW150914. For a comoving
merger rate that is consistent with current observation, eLISA is likely to
identify at least one BBH with a sufficient signal-to-noise ratio. In addition,
eLISA has a potential to measure the eccentricity of the BBH as small as $e\sim
0.02$, corresponding to the residual value $e\sim 10^{-6}$ at 10Hz. Therefore,
eLISA could provide us with a crucial information to understand the formation
processes of relatively massive BBHs like GW150914. We also derive a simple
scaling relation for the expected number of detectable Galactic BBHs.


title:
Customizable Precision of Floating-Point Arithmetic with Bitslice Vector
  Types

abstract:
  Customizing the precision of data can provide attractive trade-offs between
accuracy and hardware resources. We propose a novel form of vector computing
aimed at arrays of custom-precision floating point data. We represent these
vectors in bitslice format. Bitwise instructions are used to implement
arithmetic circuits in software that operate on customized bit-precision.
Experiments show that this approach can be efficient for vectors of
low-precision custom floating point types, while providing arbitrary bit
precision.


title: Exponentially Many 4-List-Colorings of Triangle-Free Graphs on Surfaces

abstract:
  Thomassen proved that every planar graph $G$ on $n$ vertices has at least
$2^{n/9}$ distinct $L$-colorings if $L$ is a 5-list-assignment for $G$ and at
least $2^{n/10000}$ distinct $L$-colorings if $L$ is a 3-list-assignment for
$G$ and $G$ has girth at least five. Postle and Thomas proved that if $G$ is a
graph on $n$ vertices embedded on a surface $\Sigma$ of genus $g$, then there
exist constants $\epsilon,c_g > 0$ such that if $G$ has an $L$-coloring, then
$G$ has at least $c_g2^{\epsilon n}$ distinct $L$-colorings if $L$ is a
5-list-assignment for $G$ or if $L$ is a 3-list-assignment for $G$ and $G$ has
girth at least five. More generally, they proved that there exist constants
$\epsilon,\alpha>0$ such that if $G$ is a graph on $n$ vertices embedded in a
surface $\Sigma$ of fixed genus $g$, $H$ is a proper subgraph of $G$, and
$\phi$ is an $L$-coloring of $H$ that extends to an $L$-coloring of $G$, then
$\phi$ extends to at least $2^{\epsilon(n - \alpha(g + |V(H)|))}$ distinct
$L$-colorings of $G$ if $L$ is a 5-list-assignment or if $L$ is a
3-list-assignment and $G$ has girth at least five. We prove the same result if
$G$ is triangle-free and $L$ is a 4-list-assignment of $G$, where
$\epsilon=\frac{1}{8}$, and $\alpha= 130$.


title: On weakly sequentially complete Banach spaces

abstract:
  We provide sufficient conditions for a Banach space Y to be weakly
sequentially complete. These conditions are expressed in terms of the existence
of directional derivatives for cone convex mappings with values in Y .


title: Decaying turbulence and developing chaotic attractors

abstract:
  Competition between two main attractors of the distributed chaos, one
associated with translational symmetry (homogeneity) and another associated
with rotational symmetry (isotropy), has been studied in freely decaying
turbulence. It is shown that, unlike the case of statistically stationary
homogeneous isotropic turbulence, the attractor associated with rotational
symmetry (and controlled by Loitsyanskii integral) can dominate turbulent local
dynamics in an intermediate stage of the decay, because the attractor
associated with translational symmetry (and controlled by Birkhoff-Saffman
integral) is still not developed enough. The DNS data have been used in order
to support this conclusion.


title:
A simple but precise method for solving axisymmetric contact problems
  involving elastically graded materials

abstract:
  An efficient method is presented for solving axisymmetric, frictionless
contact problems between a rigid punch and an elastically non-homogeneous,
power-law graded half-space. Provided that the contact area is simply-connected
profiles of arbitrary shape can be considered. Moreover, adhesion in the
framework of the generalized JKR-theory can be taken into account. All results
agree exactly with those given by three-dimensional contact theories. The
method uses the fact that three-dimensional contact problems can be mapped to
one-dimensional ones with a properly defined Winkler-foundation; hence, the
method is to be understood as an extension of the method of dimensionality
reduction. A prerequisite of its applicability forms the generality of contact
stiffness regardless of the geometry of the axisymmetric profile, which is
proved. All the necessary mapping rules are derived and their ease of use
explained by solving contact problems based on actual examples and up to now
unsolved problems.
  -----
  Es wird eine sehr effiziente Methode zur exakten L\"osung des
axialsymmetrischen, reibungsfreien Kontaktproblems zwischen einem starren
Indenter und einem elastisch inhomogenen Halbraum vorgestellt, dessen
Elastizit\"smodul mit der Tiefe nach einem Potenzgesetz zunimmt. Unter der
Voraussetzung einer einfach zusammenh\"angenden Kontaktfl\"ache k\"onnen
beliebig geformte Profile angenommen und auch Kontakte mit Adh\"asion gel\"ost
werden. Die Methode nutzt die Tatsache aus, dass dreidimensionale
Kontaktprobleme auf Kontaktprobleme mit einer eindimensionalen Winklerschen
Bettung abgebildet werden k\"onnen und ist daher als Erweiterung der Methode
der Dimensionsreduktion zu verstehen. In diesem Beitrag werden alle notwendigen
Abbildungsregeln hergeleitet und ihre einfache Anwendung zur L\"osung von
Kontaktproblemen anhand von aktuellen Beispielen und bisher ungel\"osten
Problemen erl\"autert.


title:
Evaluating hospital infection control measures for
  antimicrobial-resistant pathogens using stochastic transmission models:
  application to Vancomycin-Resistant Enterococci in intensive care units

abstract:
  Nosocomial pathogens such as Methicillin-Resistant {\em Staphylococcus
aureus} (MRSA) and Vancomycin-resistant {\em Enterococci} (VRE) are the cause
of significant morbidity and mortality among hospital patients. It is important
to be able to assess the efficacy of control measures using data on patient
outcomes. In this paper we describe methods for analysing such data using
patient-level stochastic models which seek to describe the underlying
unobserved process of transmission. The methods are applied to detailed
longitudinal patient-level data on VRE from a study in a US hospital with eight
intensive care units (ICUs). The data comprise admission and discharge dates,
dates and results of screening tests, and dates during which precautionary
measures were in place for each patient during the study period. Results
include estimates of the efficacy of the control measures, the proportion of
unobserved patients colonized with VRE and the proportion of patients colonized
on admission.


title:
Ultrahigh molecular recognition specificity of competing DNA
  oligonucleotide strands in thermal equilibrium: a cooperative transition to
  order

abstract:
  The specificity of molecular recognition is important to molecular
self-organization. A prominent example is the biological cell where, within a
highly crowded molecular environment, a myriad of different molecular receptor
pairs recognize their binding partner with astonishing accuracy. In thermal
equilibrium it is usually admitted that the affinity of recognizer pairs only
depends on the nature of the two binding molecules. Accordingly, Boltzmann
factors of binding energy differences relate the molecular affinities among
different target molecules that compete for the same probe. Here, we consider
the molecular recognition of short DNA oligonucleotide single strands. We show
that a better matching oligonucleotide strand can prevail against a
disproportionally more concentrated competitor that exhibits reduced affinity
due to a mismatch. The magnitude of deviation from the simple picture above may
reach several orders of magnitude. In our experiments the effective molecular
affinity of a given strand remains elevated only as long as the better matching
competitor is not present. We interpret our observations based on an
energy-barrier of entropic origin that occurs if two competing oligonucleotide
strands occupy the same probe simultaneously. In this situation the relative
binding affinities are reduced asymmetrically, which leads to an expression of
the free energy landscape that represents a formal analogue of a Landau
description of phase transitions. Our mean field description reproduces the
observations in quantitative agreement. The advantage of improved molecular
recognition comes at no energetic cost other than the design of the molecular
ensemble, and the introduction of the competitor. It will be interesting to see
if mechanisms along similar lines as exposed here, contribute to the molecular
synergy that occurs in biological systems.

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


title:
Efficient Representation of Low-Dimensional Manifolds using Deep
  Networks

abstract:
  We consider the ability of deep neural networks to represent data that lies
near a low-dimensional manifold in a high-dimensional space. We show that deep
networks can efficiently extract the intrinsic, low-dimensional coordinates of
such data. We first show that the first two layers of a deep network can
exactly embed points lying on a monotonic chain, a special type of piecewise
linear manifold, mapping them to a low-dimensional Euclidean space. Remarkably,
the network can do this using an almost optimal number of parameters. We also
show that this network projects nearby points onto the manifold and then embeds
them with little error. We then extend these results to more general manifolds.


title:
Functional determinants and Casimir energy in higher dimensional
  spherically symmetric background potentials

abstract:
  In this paper we analyze the spectral zeta function associated with a Laplace
operator acting on scalar functions on an N-dimensional Euclidean space in the
presence of a spherically symmetric background potential. The obtained analytic
continuation of the spectral zeta function is then used to derive very simple
results for the functional determinant of the operator and the Casimir energy
of the scalar field.


title: Stress Induced Charge-Ordering Process in LiMn2O4

abstract:
  In this letter we report the stress induced Mn charge-ordering process in the
LiMn2O4 spinel, evidenced by the lattice strain evolutions due to the
Jahn-Teller effects. In-situ neutron diffraction, reveals that the initial
stage of this process at low stress, indicating the eg electron localization at
the preferential Mn sites during the early phase transition, as an underlying
charge ordering mechanism in the charge-frustrated LiMn2O4. The initial stage
of this transition exhibits as a progressive lattice and charge evolution,
without showing a first-order behavior.


title:
The Rank Theorem and $L^2$-invariants in Free Entropy: Global Upper
  Bounds

abstract:
  Using an analogy with the rank theorem in differential geometry, it is shown
that for a finite $n$-tuple $X$ in a tracial von Neumann algebra and any finite
$m$-tuple $F$ of $*$-polynomials in $n$ noncommuting indeterminates,
\begin{eqnarray*} \delta_0(X) & \leq & \text{Nullity}(D^sF(X)) +
\delta_0(F(X):X) \end{eqnarray*} where $\delta_0$ is the (modified) microstates
free entropy dimension and $D^sF(X)$ is a kind of derivative of $F$ evaluated
at $X$. When $F(X) =0$ and $|D^sF(X)|$ has nonzero Fuglede-Kadison-L\"uck
determinant, then $X$ is $\alpha$-bounded in the sense of \cite{j3} where
$\alpha = \text{Nullity}(D^sF(X))$. Using Linnell's $L^2$ integral domain
results in \cite{l} as well as Elek and Szab\'o's work on L\"uck's determinant
conjecture for sofic groups in \cite{es} the following result is proven.
Suppose $\Gamma$ is a sofic, left-orderable, discrete group with 2 generators
and $\Gamma \neq \{0\}$. The following conditions are equivalent:
  (1) $\Gamma \not\simeq \mathbb F_2$.
  (2) $L(\Gamma) \not\simeq L(\mathbb F_2)$.
  (3) $L(\Gamma)$ is strongly $1$-bounded.
  (4) $\delta_0(X) = 1$ for any finite set of generators $X$ for $L(\Gamma)$.
  From Brodski\u{i} and Howie's results on local indicability (\cite{b},
\cite{h}), it follows that a sofic, torsion-free, one-relator group von Neumann
algebra on two generators with nontrivial relator is strongly $1$-bounded. It
also follows from the residual solvability of the positive one relator groups
(\cite{baum}) that a one-relator group von Neumann algebra on two generators
whose relator is a nontrivial, positive, non-proper word in the generators is
strongly $1$-bounded.


title: Tangles and Connectivity in Graphs

abstract:
  This paper is a short introduction to the theory of tangles, both in graphs
and general connectivity systems. An emphasis is put on the correspondence
between tangles of order k and k-connected components. In particular, we prove
that there is a one-to-one correspondence between the triconnected components
of a graph and its tangles of order 3.


title:
Inverse problems, non-roundness and flat pieces of the effective burning
  velocity from an inviscid quadratic Hamilton-Jacobi model

abstract:
  The main goal of this paper is to understand finer properties of the
effective burning velocity from a combustion model introduced by Majda and
Souganidis [19]. Motivated by results in [4] and applications in turbulent
combustion, we show that when the dimension is two and the flow of the ambient
fluid is either weak or very strong, the level set of the effective burning
velocity has flat pieces. Due to the lack of an applicable Hopf-type rigidity
result, we need to identify the exact location of at least one flat piece.
Implications on the effective flame front and other related inverse type
problems are also discussed.


title: Volterra operators on Hardy spaces of Dirichlet series

abstract:
  For a Dirichlet series symbol $g(s) = \sum_{n \geq 1} b_n n^{-s}$, the
associated Volterra operator $\mathbf{T}_g$ acting on a Dirichlet series
$f(s)=\sum_{n\ge 1} a_n n^{-s}$ is defined by the integral $f\mapsto
-\int_{s}^{+\infty} f(w)g'(w)\,dw$. We show that $\mathbf{T}_g$ is a bounded
operator on the Hardy space $\mathcal{H}^p$ of Dirichlet series with $0 < p <
\infty$ if and only if the symbol $g$ satisfies a Carleson measure condition.
When appropriately restricted to one complex variable, our condition coincides
with the standard Carleson measure characterization of
${\operatorname{BMOA}}(\mathbb{D})$. A further analogy with classical
${\operatorname{BMO}}$ is that $\exp(c|g|)$ is integrable (on the infinite
polytorus) for some $c > 0$ whenever $\mathbf{T}_g$ is bounded. In particular,
such $g$ belong to $\mathcal{H}^p$ for every $p < \infty$. We relate the
boundedness of $\mathbf{T}_g$ to several other ${\operatorname{BMO}}$ type
spaces: ${\operatorname{BMOA}}$ in half-planes, the dual of $\mathcal{H}^1$,
and the space of symbols of bounded Hankel forms. Moreover, we study symbols
whose coefficients enjoy a multiplicative structure and obtain coefficient
estimates for $m$-homogeneous symbols as well as for general symbols. Finally,
we consider the action of $\mathbf{T}_g$ on reproducing kernels for appropriate
sequences of subspaces of $\mathcal{H}^2$. Our proofs employ function and
operator theoretic techniques in one and several variables; a variety of number
theoretic arguments are used throughout the paper in our study of special
classes of symbols $g$.


title:
Effective results for discriminant equations over finitely generated
  domains

abstract:
  Let $A$ be an integral domain with quotient field $K$ of characteristic $0$
that is finitely generated as a $\mathbb{Z}$-algebra. Denote by $D(F)$ the
discriminant of a polynomial $F\in A[X]$. Further, given a finite etale algebra
$\Omega$, we denote by $D_{\Omega/K}(\alpha )$ the discriminant of $\alpha$
over $K$. For non-zero $\delta\in A$, we consider equations \[ D(F)=\delta \]
to be solved in monic polynomials $F\in A[X]$ of given degree $n\geq 2$ having
their zeros in a given finite extension field $G$ of $K$, and \[
D_{\Omega/K}(\alpha)=\delta\,\,\mbox{ in } \alpha\in O, \] where $O$ is an
$A$-order of $\Omega$, i.e., a subring of the integral closure of $A$ in
$\Omega$ that contains $A$ as well as a $K$-basis of $\Omega$.
  In our book ``Discriminant Equations in Diophantine Number Theory, which will
be published by Cambridge University Press we proved that if $A$ is effectively
given in a well-defined sense and integrally closed, then up to natural notions
of equivalence the above equations have only finitely many solutions, and that
moreover, a full system of representatives for the equivalence classes can be
determined effectively. In the present paper, we extend these results to
integral domains $A$ that are not necessarily integrally closed.


title: Approximation to an extremal number, its square and its cube

abstract:
  We study rational approximation properties for successive powers of extremal
numbers defined by Roy. For $n\in{\{1,2\}}$, the classic approximation
constants
$\lambda_{n}(\zeta),\hat{\lambda}_{n}(\zeta),w_{n}(\zeta),\hat{w}_{n}(\zeta)$
connected to an extremal number $\zeta$ have been established and in fact much
more is known. However, so far almost nothing had been known for $n\geq 3$. In
this paper we determine all classic approximation constants as above for $n=3$.
Our methods will more generally provide detailed information on the combined
graph defined by Schmidt and Summerer assigned to an extremal number, its
square and its cube. We provide some results for $n=4$ as well. In the course
of the proof of the main results we establish a very general connection between
Khintchine's transference inequalities and uniform approximation.


title: Affine computation and affine automaton

abstract:
  We introduce a quantum-like classical computational model, called affine
computation, as a generalization of probabilistic computation. After giving the
basics of affine computation, we define affine finite automata (AfA) and
compare it with quantum and probabilistic finite automata (QFA and PFA,
respectively) with respect to three basic language recognition modes. We show
that, in the cases of bounded and unbounded error, AfAs are more powerful than
QFAs and PFAs, and, in the case of nondeterministic computation, AfAs are more
powerful than PFAs but equivalent to QFAs.


title: Sensitivity study for s process nucleosynthesis in AGB stars

abstract:
  In this paper we present a large-scale sensitivity study of reaction rates in
the main component of the $s$ process. The aim of this study is to identify all
rates, which have a global effect on the $s$ process abundance distribution and
the three most important rates for the production of each isotope. We have
performed a sensitivity study on the radiative $^{13}$C-pocket and on the
convective thermal pulse, sites of the $s$ process in AGB stars. We identified
22 rates, which have the highest impact on the $s$-process abundances in AGB
stars.


title:
Current issues in finite-$T$ density-functional theory and
  Warm-Correlated Matter

abstract:
  Finite-temperature DFT has become of topical interest, partly due to the
increasing ability to create novel states of warm-correlated matter (WCM).
Subclasses of WCM are Warm-dense matter (WDM), ultra-fast matter (UFM), and
high-energy density matter (HEDM), containing electyrons (e) and ions (i).
Strong e-e, i-i and e-i correlation effects and partial degeneracies are found
in these systems where the electron temperature $T_e $ is comparable to the
electron Fermi energy. The ion subsystem may be solid, liquid or plasma, with
many states of ionization with ionic charge $Z_j$. Quasi-equilibria with the
ion temperature $T_i\ne T_e$ are common. The ion subsystem in WCM can no longer
be treated as a passive "external potential", as is customary in $T=0$ density
functional theory (DFT) dominated by solid-state theory or quantum chemistry.
Hohenberg-Kohn-Mermin theory can be used for WCMs if finite-$T$
exchange-correlation (XC) functionals are available. They are functionals of
both the one-body electron density $n_e$ and the one-body ion densities
$\rho_j$. A method of approximately but accurately mapping the quantum
electrons to a classical Coulomb gas enables one to treat electron-ion systems
entirely classically at any temperature and arbitrary spin polarization, using
exchange-correlation effects calculated {\it in situ}, directly from the
pair-distribution functions. This eliminates the need for any XC-functionals,
or the use of a Born-Oppenheimer approximation. This classical map has been
used to calculate the equation of state of WDM systems, and construct a
finite-$T$ XC functional that is found to be in close agreement with recent
quantum path-integral simulation data. In this review current developments and
concerns in finite-$T$ DFT, especially in the context of non-relativistic
warm-dense matter and ultra-fast matter will be presented.


title: Electromagnetic Counterparts to Black Hole Mergers Detected by LIGO

abstract:
  Mergers of stellar-mass black holes (BHs), such as GW150914 observed by LIGO,
are not expected to have electromagnetic counterparts. However, the Fermi GBM
detector identified of a gamma-ray transient 0.4 s after the gravitational wave
(GW) signal GW150914 with consistent sky localization. I show that the two
signals might be related if the BH binary detected by LIGO originated from two
clumps in a dumbbell configuration that formed when the core of a rapidly
rotating massive star collapsed. In that case, the BH binary merger was
followed by a gamma-ray burst (GRB) from a jet that originated in the accretion
flow around the remnant BH. A future detection of a GRB afterglow could be used
to determine the redshift and precise localization of the source. A population
of standard GW sirens with GRB redshifts would provide a new approach for
precise measurements of cosmological distances as a function of redshift.

categories: astro-ph.HE astro-ph.CO astro-ph.SR gr-qc hep-ph


title: Footprints of a possible Ceres asteroid paleo-family

abstract:
  Ceres is the largest and most massive body in the asteroid main belt.
Observational data from the Dawn spacecraft reveal the presence of at least two
impact craters about 280~km in diameter on the Ceres surface, that could have
expelled a significant number of fragments. Yet, standard techniques for
identifying dynamical asteroid families have not detected any Ceres family. In
this work, we argue that linear secular resonances with Ceres deplete the
population of objects near Ceres. Also, because of the high escape velocity
from Ceres, family members are expected to be very dispersed, with a
considerable fraction of km-sized fragments that should be able to reach the
pristine region of the main belt, the area between the 5J:-2A and 7J:-3A
mean-motion resonances, where the observed number of asteroids is low. Rather
than looking for possible Ceres family members near Ceres, here we propose to
search in the pristine region. We identified 156 asteroids whose taxonomy,
colors, albedo could be compatible with being fragments from Ceres. Remarkably,
most of these objects have inclinations near that of Ceres itself.


title: The effect of ambipolar diffusion on low-density molecular ISM filaments

abstract:
  The filamentary structure of the molecular interstellar medium and the
potential link of this morphology to star formation have been brought into
focus recently by high resolution observational surveys. An especially puzzling
matter is that local interstellar filaments appear to have the same thickness,
independent of their column density. This requires a theoretical understanding
of their formation process and the physics that governs their evolution. In
this work we explore a scenario in which filaments are dissipative structures
of the large-scale interstellar turbulence cascade and ion-neutral friction
(also called ambipolar diffusion) is affecting their sizes by preventing
small-scale compressions. We employ high-resolution, 3D MHD simulations,
performed with the grid code RAMSES, to investigate non-ideal MHD turbulence as
a filament formation mechanism. We focus the analysis on the mass and thickness
distributions of the resulting filamentary structures. Simulations of both
driven and decaying MHD turbulence show that the morphologies of the density
and the magnetic field are different when ambipolar diffusion is included in
the models. In particular, the densest structures are broader and more massive
as an effect of ion-neutral friction and the power spectra of both the velocity
and the density steepen at a smaller wavenumber. The comparison between ideal
and non-ideal MHD simulations shows that ambipolar diffusion causes a shift of
the filament thickness distribution towards higher values. However, none of the
distributions exhibit the pronounced peak found in the observed local
filaments. Limitations in dynamical range and the absence of self-gravity in
these numerical experiments do not allow us to conclude at this time whether
this is due to the different filament selection or due to the physics inherent
of the filament formation.


title:
Detection of gravitational waves from black holes: Is there a window for
  alternative theories?

abstract:
  Recently LIGO and VIRGO collaborations reported about observation of
gravitational-wave signal corresponding to the inspiral and merger of two black
holes, resulting into formation of the final black hole. It was shown that the
observations are consistent with the Einstein theory of gravity with high
accuracy limited mainly by the statistical error. Angular momentum and mass of
the final black hole were determined with rather large allowance of tens of
percents. Here we shall show that this indeterminacy in the range of the
black-hole parameters allows for some not negligible deformations of the Kerr
spacetime leading to the same frequencies of black-hole ringing. This means
that at the current precision of the experiment there remain some possibilities
for alternative theories of gravity.


title: Spin goups of super metrics and a Theorem of Rogers

abstract:
  We derive the canonical forms of super Riemannian metrics and the local
isometry groups of such metrics. For certain super metrics we also compute the
simply connected covering groups of the local isometry groups and interpret
these as local spin groups of the super metric. Using a generalization of a
Theorem of Rogers, which is itself one of the main results of this paper, we
show that for super metrics we call body reducible, each such simply connected
covering group G is a super Lie group with a conventional super Lie algebra as
its corresponding super Lie algebra. We work exclusively in the $G^{\infty}$
category.


title:
Asymptotics of stochastic 2D Hydrodynamical type systems in unbounded
  domains

abstract:
  In this paper, we prove a central limit theorem and establish a moderate
deviation principle for 2D stochastic hydrodynamical type systems with
multiplicative noise in unbounded domains, which covers 2D Navier-Stokes
equations, 2D MHD models and the 2D magnetic B?enard problem and also shell
models of turbulence. The weak convergence method plays an important role in
obtaining the moderate deviation principle.


title: Delay and Cooperation in Nonstochastic Bandits

abstract:
  We study networks of communicating learning agents that cooperate to solve a
common nonstochastic bandit problem. Agents use an underlying communication
network to get messages about actions selected by other agents, and drop
messages that took more than $d$ hops to arrive, where $d$ is a delay
parameter. We introduce \textsc{Exp3-Coop}, a cooperative version of the {\sc
Exp3} algorithm and prove that with $K$ actions and $N$ agents the average
per-agent regret after $T$ rounds is at most of order $\sqrt{\bigl(d+1 +
\tfrac{K}{N}\alpha_{\le d}\bigr)(T\ln K)}$, where $\alpha_{\le d}$ is the
independence number of the $d$-th power of the connected communication graph
$G$. We then show that for any connected graph, for $d=\sqrt{K}$ the regret
bound is $K^{1/4}\sqrt{T}$, strictly better than the minimax regret $\sqrt{KT}$
for noncooperating agents. More informed choices of $d$ lead to bounds which
are arbitrarily close to the full information minimax regret $\sqrt{T\ln K}$
when $G$ is dense. When $G$ has sparse components, we show that a variant of
\textsc{Exp3-Coop}, allowing agents to choose their parameters according to
their centrality in $G$, strictly improves the regret. Finally, as a by-product
of our analysis, we provide the first characterization of the minimax regret
for bandit learning with delay.


title: Training of spiking neural networks based on information theoretic costs

abstract:
  Spiking neural network is a type of artificial neural network in which
neurons communicate between each other with spikes. Spikes are identical
Boolean events characterized by the time of their arrival. A spiking neuron has
internal dynamics and responds to the history of inputs as opposed to the
current inputs only. Because of such properties a spiking neural network has
rich intrinsic capabilities to process spatiotemporal data. However, because
the spikes are discontinuous 'yes or no' events, it is not trivial to apply
traditional training procedures such as gradient descend to the spiking
neurons. In this thesis we propose to use stochastic spiking neuron models in
which probability of a spiking output is a continuous function of parameters.
We formulate several learning tasks as minimization of certain
information-theoretic cost functions that use spiking output probability
distributions. We develop a generalized description of the stochastic spiking
neuron and a new spiking neuron model that allows to flexibly process rich
spatiotemporal data. We formulate and derive learning rules for the following
tasks:
  - a supervised learning task of detecting a spatiotemporal pattern as a
minimization of the negative log-likelihood (the surprisal) of the neuron's
output
  - an unsupervised learning task of increasing the stability of neurons output
as a minimization of the entropy
  - a reinforcement learning task of controlling an agent as a modulated
optimization of filtered surprisal of the neuron's output.
  We test the derived learning rules in several experiments such as
spatiotemporal pattern detection, spatiotemporal data storing and recall with
autoassociative memory, combination of supervised and unsupervised learning to
speed up the learning process, adaptive control of simple virtual agents in
changing environments.


title: Order isotonicity of the metric projection onto a closed convex cone

abstract:
  The basic tool for solving problems in metric geometry and isotonic
regression is the metric projection onto closed convex cones. Isotonicity of
these projections with respect to a given order relation can facilitate finding
the solutions of the above problems. In the recent note "A. B. N\'emeth and
S.Z. N\'emeth: Isotonic regression and isotonic projection. Linear Algebra and
its Applications, 494: 80-89 (2016)" this problem was studied for the
coordinate-wise ordering. This study was the starting point for further
investigations, such as the ones presented here. The order relation in the
Euclidean space endowed by a proper cone is considered and the proper cones
admitting isotone metric projections with respect to this order relation are
investigated.


title: A Simplified Stabilizer ZX-calculus

abstract:
  The stabilizer ZX-calculus is a rigorous graphical language for reasoning
about quantum mechanics.The language is sound and complete: a stabilizer
ZX-diagram can be transformed into another one if and only if these two
diagrams represent the same quantum evolution or quantum state. We show that
the stabilizer ZX-calculus can be simplified, removing unnecessary equations
while keeping only the essential axioms which potentially capture fundamental
structures of quantum mechanics. We thus give a significantly smaller set of
axioms and prove that meta-rules like 'colour symmetry' and 'upside-down
symmetry', which were considered as axioms in previous versions of the
language, can in fact be derived. In particular, we show that the additional
symbol and one of the rules which had been recently introduced to keep track of
scalars (diagrams with no inputs or outputs) are not necessary.


title:
Helicity is the only integral invariant of volume-preserving
  transformations

abstract:
  We prove that any regular integral invariant of volume-preserving
transformations is equivalent to the helicity. Specifically, given a functional
$\mathcal I$ defined on exact divergence-free vector fields of class $C^1$ on a
compact 3-manifold that is associated with a well-behaved integral kernel, we
prove that $\mathcal I$ is invariant under arbitrary volume-preserving
diffeomorphisms if and only if it is a function of the helicity.


title: Eikonal equations and pathwise solutions to fully non-linear SPDEs

abstract:
  We study the existence and uniqueness of the stochastic viscosity solutions
of fully nonlinear, possibly degenerate, second order stochastic pde with
quadratic Hamiltonians associated to a Riemannian geometry. The results are new
and extend the class of equations studied so far by the last two authors.


title: Secure symmetric ciphers over the real field

abstract:
  Most cryptosystems are defined over finite algebraic structures where
arithmetic operations are performed modulo natural numbers. This applies to
private key as well as to public key ciphers. No secure cryptosystems defined
over the field of real numbers are known. In this work, we demonstrate the
feasibility of constructing secure symmetric key ciphers defined over the field
of real numbers. We consider the security of ciphers introduced in a previous
work and based on solving linear and non-linear equations numerically. We
complement the design of those ciphers to satisfy the requirements of secure
systems and, consequently, extend them into composite ciphers with multiple
encryptions. We show security enhancements by estimating the uncertainty in
finding the keys using a measure based on Shannon's entropy function.


abstract:
  Using a method of F\'elix and Thomas we compute the Betti numbers of
unordered configuration spaces of the torus.


title: Weighted Fourier frames on fractal measures

abstract:
  We generalize an idea of Picioroaga and Weber to construct Paseval frames of
weighted exponential functions for self-affine measures.


abstract:
  This paper gives a review of the recent progress in the study of Fourier
bases and Fourier frames on self-affine measures. In particular, we emphasize
the new matrix analysis approach for checking the completeness of a mutually
orthogonal set. This method helps us settle down a long-standing conjecture
that Hadamard triples generates self-affine spectral measures. It also gives us
non-trivial examples of fractal measures with Fourier frames. Furthermore, a
new avenue is open to investigate whether the Middle Third Cantor measure
admits Fourier frames.


title:
Disruption of Planetary Orbits Through Evection Resonance with an
  External Companion: Circumbinary Planets and Multiplanet Systems

abstract:
  Planets around binary stars and those in multiplanet systems may experience
resonant eccentricity excitation and disruption due to perturbations from a
distant stellar companion. This "evection resonance" occurs when the apsidal
precession frequency of the planet, driven by the quadrupole associated with
the inner binary or the other planets, matches the orbital frequency of the
external companion. We develop an analytic theory to study the effects of
evection resonance on circumbinary planets and multiplanet systems. We derive
the general conditions for effective eccentricity excitation or resonance
capture of the planet as the system undergoes long-term evolution. Applying to
circumbinary planets, we show that inward planet migration may lead to
eccentricity growth due to evection resonance with an external perturber, and
planets around shrinking binaries may not survive the resonant eccentricity
growth. On the other hand, significant eccentricity excitation in multiplanet
systems occurs in limited parameter space of planet and binary semimajor axes,
and requires the planetary migration to be sufficiently slow.


title: Testing cosmology with a catalogue of voids in the BOSS galaxy surveys

abstract:
  We present a public catalogue of voids in the Baryon Oscillation
Spectroscopic Survey (BOSS) Data Release 11 LOWZ and CMASS galaxy surveys. This
catalogue contains information on the location, sizes, densities, shapes and
bounding surfaces of 8956 independent, disjoint voids, making it the largest
public void catalogue to date. Voids are identified using a version of the
ZOBOV algorithm, the operation of which has been calibrated through tests on
mock galaxy populations in N-body simulations, as well as on a suite of 4096
mock catalogues which fully reproduce the galaxy clustering, survey masks and
selection functions. Based on this, we estimate a false positive detection rate
of 3%. Comparison with mock catalogues limits deviations of the void size
distribution from that predicted in the $\Lambda$CDM model to be less than 6%
for voids with effective radius $8<R_v<60\,h^{-1}$Mpc and in the redshift range
$0.15<z<0.7$. This could tightly constrain modified gravity scenarios and
models with a varying equation of state, but we identify systematic biases
which must be accounted for to reduce the theoretical uncertainty in the
predictions for these models to the current level of precision attained from
the data. We also examine the distribution of void densities and identify a
deficit of the deepest voids relative to $\Lambda$CDM expectations, which is
significant at more than the $3\sigma$ equivalent level. We discuss possible
explanations for this discrepancy but at present its cause remains unknown.


title:
Resonant second-harmonic-generation circular-dichroism microscopy
  reveals molecular chirality in native biological tissues

abstract:
  Conventional linear optical activity effects are widely used for studying
chiral materials. However, poor contrast and artifacts due to sample anisotropy
limit the applicability of these methods. Here we demonstrate that nonlinear
second-harmonic-generation circular dichroism spectral microscopy can overcome
these limits. In intact collagenous tissues, clear spectral resonance is
observed with sub-micrometer spatial resolution. By performing gradual protein
denaturation studies, we show that the resonant responses are dominantly due to
the molecular chirality.


title: Towards Robot Task Planning From Probabilistic Models of Human Skills

abstract:
  We describe an algorithm for motion planning based on expert demonstrations
of a skill. In order to teach robots to perform complex object manipulation
tasks that can generalize robustly to new environments, we must (1) learn a
representation of the effects of a task and (2) find an optimal trajectory that
will reproduce these effects in a new environment. We represent robot skills in
terms of a probability distribution over features learned from multiple expert
demonstrations. When utilizing a skill in a new environment, we compute feature
expectations over trajectory samples in order to stochastically optimize the
likelihood of a trajectory in the new environment. The purpose of this method
is to enable execution of complex tasks based on a library of probabilistic
skill models. Motions can be combined to accomplish complex tasks in hybrid
domains. Our approach is validated in a variety of case studies, including an
Android game, simulated assembly task, and real robot experiment with a UR5.


title:
A numerical investigation of coorbital stability and libration in three
  dimensions

abstract:
  Motivated by the dynamics of resonance capture, we study numerically the
coorbital resonance for inclination180 >=I>=0 in the circular restricted
three-body problem. We examine the similarities and differences between planar
and three dimensional coorbital resonance capture and seek their origin in the
stability of coorbital motion at arbitrary inclination. After we present
stability maps of the planar prograde and retrograde coorbital resonances, we
characterize the new coorbital modes in three dimensions. We see that
retrograde mode I (R1) and mode II (R2) persist as we change the relative
inclination, while retrograde mode III (R3) seems to exist only in the planar
problem. A new coorbital mode (R4) appears in 3D which is a retrograde analogue
to an horseshoe-orbit. The Kozai-Lidov resonance is active for retrograde
orbits as well as prograde orbits and plays a key role in coorbital resonance
capture. Stable coorbital modes exist at all inclinations, including retrograde
and polar obits. This result confirms the robustness the coorbital resonance at
large inclination and encourages the search for retrograde coorbital companions
of the solar system's planets.


title: Levy's phenomenon for analytic functions in the polydisc

abstract:
  In this paper we prove some analogue of Wiman's type inequality for random
analytic functions in the polydisc $\mathbb{D}^p=\{z\in\mathbb{C}^p\colon
|z_j|<1, j\in\{1,\ldots,p\}\},\ p\in\mathbb{Z}_+$. The obtained inequality is
sharp.


title: Polariton Spin Whirls

abstract:
  We report on the observation of spin whirls in a radially expanding polariton
condensate formed under non-resonant optical excitation. Real space imaging of
polarization- and time-resolved photoluminescence reveal a spiralling
polarization pattern in the plane of the microcavity. Simulations of the
spatiotemporal dynamics of a spinor condensate reveal the crucial role of
polariton interactions with a spinor exciton reservoir. Harnessing spin
dependent interactions between the exciton reservoir and polariton condensates
allows for the manipulation of spin currents and the realization of dynamic
collective spin effects in solid state systems.


title:
Convergent semi-Lagrangian methods for the Monge-Amp\`ere equation on
  unstructured grids

abstract:
  This paper is concerned with developing and analyzing convergent
semi-Lagrangian methods for the fully nonlinear elliptic Monge-Amp\`ere
equation on general triangular grids. This is done by establishing an
equivalent (in the viscosity sense) Hamilton-Jacobi-Bellman formulation of the
Monge-Amp\`ere equation. A significant benefit of the reformulation is the
removal of the convexity constraint from the admissible space as convexity
becomes a built-in property of the new formulation. Moreover, this new approach
allows one to tap the wealthy numerical methods, such as semi-Lagrangian
schemes, for Hamilton-Jacobi-Bellman equations to solve Monge-Amp\`ere type
equations. It is proved that the considered numerical methods are monotone,
pointwise consistent and uniformly stable. Consequently, its solutions converge
uniformly to the unique convex viscosity solution of the Monge-Amp\`ere
Dirichlet problem. A super-linearly convergent Howard's algorithm, which is a
Newton type method, is utilized as the nonlinear solver to take advantage of
the monotonicity of the scheme. Numerical experiments are also presented to
gauge the performance of the proposed numerical method and the nonlinear
solver.


title: Applied Antineutrino Physics 2015 -- Conference Summary

abstract:
  This is a brief summary of the 11th Applied Antineutrino Physics 2015
workshop held at the Virginia Tech Arlington Research Facility from December
7-8, 2015.


title:
Piecewise conjugacy for multivariable dynamics over the Jacobson
  spectrum of a C*-algebra

abstract:
  We show that if (A,a) and (B,b) are automorphic multivariable C*-dynamical
systems with isometrically isomorphic tensor algebras (or semi crossed
products), then the systems are piecewise conjugate over their Jacobson
spectrum. This answers a question of Kakariadis and the author.


title:
Back reaction effects on the dynamics of heavy probes in heavy quark
  cloud

abstract:
  We holographically study the effect of back reaction on the hydrodynamical
properties of $\mathcal{N} = 4$ strongly coupled super Yang-Mills (SYM) thermal
plasma. The back reaction we consider arises from the presence of static heavy
quarks uniformly distributed over $\mathcal{N} = 4$ SYM plasma. In order to
study the hydrodynamical properties, we use heavy quark as well as heavy
quark-antiquark bound state as probes and compute the jet quenching parameter,
screening length and binding energy. We also consider the rotational dynamics
of heavy probe quark in the back-reacted plasma and analyse associated energy
loss. We observe that the presence of back reaction enhances the energy-loss in
the thermal plasma. Finally, we show that there is no effect of angular drag on
the rotational motion of quark-antiquark bound state probing the back reacted
thermal plasma.


title:
Optimized and Trusted Collision Avoidance for Unmanned Aerial Vehicles
  using Approximate Dynamic Programming (Technical Report)

abstract:
  Safely integrating unmanned aerial vehicles into civil airspace is contingent
upon development of a trustworthy collision avoidance system. This paper
proposes an approach whereby a parameterized resolution logic that is
considered trusted for a given range of its parameters is adaptively tuned
online. Specifically, to address the potential conservatism of the resolution
logic with static parameters, we present a dynamic programming approach for
adapting the parameters dynamically based on the encounter state. We compute
the adaptation policy offline using a simulation-based approximate dynamic
programming method that accommodates the high dimensionality of the problem.
Numerical experiments show that this approach improves safety and operational
performance compared to the baseline resolution logic, while retaining
trustworthiness.


title: On the number of bases of almost all matroids

abstract:
  For a matroid $M$ of rank $r$ on $n$ elements, let $b(M)$ denote the fraction
of bases of $M$ among the subsets of the ground set with cardinality $r$. We
show that $$\Omega(1/n)\leq 1-b(M)\leq O(\log(n)^3/n)\text{ as }n\rightarrow
\infty$$ for asymptotically almost all matroids $M$ on $n$ elements. We derive
that asymptotically almost all matroids on $n$ elements (1) have a
$U_{k,2k}$-minor, whenever $k\leq O(\log(n))$, (2) have girth $\geq
\Omega(\log(n))$, (3) have Tutte connectivity $\geq \Omega(\sqrt{\log(n)})$,
and (4) do not arise as the truncation of another matroid.
  Our argument is based on a refined method for writing compressed descriptions
of any given matroid, which allows bounding the number of matroids in a class
relative to the number of sparse paving matroids.


title: Comments on Graviton Propagation in Light of GW150914

abstract:
  The observation of gravitational waves from the Laser Interferometer
Gravitational-Wave Observatory (LIGO) event GW150914 may be used to constrain
the possibility of Lorentz violation in graviton propagation, and the
observation by the Fermi Gamma-Ray Burst Monitor of a transient source in
apparent coincidence may be used to constrain the difference between the
velocities of light and gravitational waves: $c_g - c_\gamma < 10^{-17}$.

categories: gr-qc astro-ph.CO astro-ph.HE hep-ph hep-th


title:
Resolved gravity duals of ${\cal N}=4$ quiver field theories in 2+1
  dimensions

abstract:
  We generalize the construction by Aharony, Hashimoto, Hirano, and Ouyang of
${\cal N}=4$ quiver gauge theory with gauge group $U(N+M) \times U(N)$, $k$
fundamentals charged under $U(N)$ and bi-fundamentals, to the case with gauge
group $\prod_{i=1}^{\hat k} U(N_i)$ with $k_i$ fundamentals charged under
$U(N_i)$. This construction is facilitated by considering the resolved
$ALE_{\hat k} \times TN_{k}$ background in M-theory including non-trivial
fluxes through the resolved 4-cycles in the geometry. We also describe the
M-theory lift of the IIA Page charge quantization condition. Finally, we
clarify the role of string corrections in various regimes of parameter space.


title:
Slowly rotating neutron stars in scalar-tensor theories with a massive
  scalar field

abstract:
  In the scalar-tensor theories with a massive scalar field the coupling
constants, and the coupling functions in general, which are observationally
allowed, can differ significantly from those in the massless case. This fact
naturally implies that the scalar-tensor neutron stars with a massive scalar
field can have rather different structure and properties in comparison with
their counterparts in the massless case and in general relativity. In the
present paper we study slowly rotating neutron stars in scalar-tensor theories
with a massive gravitational scalar. Two examples of scalar-tensor theories are
examined - the first example is the massive Brans-Dicke theory and the second
one is a massive scalar-tensor theory indistinguishable from general relativity
in the weak field limit. In the later case we study the effect of the scalar
field mass on the spontaneous scalarization of neutron stars. Our numerical
results show that the inclusion of a mass term for the scalar field indeed
changes the picture drastically compared to the massless case. It turns out
that mass, radius and moment of inertia for neutron stars in massive
scalar-tensor theories can differ drastically from the pure general
relativistic solutions if sufficiently large masses of the scalar field are
considered.


title:
Double-heralded generation of two-photon-states by spontaneous
  four-wave-mixing in the presence of noise

abstract:
  We present an experimental method for creating and verifying photon-number
states created by non-degenerate, third-order nonlinear-optical photon-pair
sources. By using spatially multiplexed, thresholding single-photon detectors
and inverting a conditional probability matrix, we determine the photon-number
probabilities created through heralded spontaneous four-wave-mixing. The
deleterious effects of noise photons on reliable heralding are investigated and
shown to degrade the conditional preparation of two-photon number states more
than they degrade conditional single-photon states. We derive the equivalence
between the presence of unwanted noise in the herald channel and loss in the
signal channel of heralded experiments. A procedure for characterizing the
noise-photon contributions, and a means of estimating the herald noise-free
photon-number distribution is demonstrated.


title:
Demonstrating Quantum Error Correction that Extends the Lifetime of
  Quantum Information

abstract:
  The remarkable discovery of Quantum Error Correction (QEC), which can
overcome the errors experienced by a bit of quantum information (qubit), was a
critical advance that gives hope for eventually realizing practical quantum
computers. In principle, a system that implements QEC can actually pass a
"break-even" point and preserve quantum information for longer than the
lifetime of its constituent parts. Reaching the break-even point, however, has
thus far remained an outstanding and challenging goal. Several previous works
have demonstrated elements of QEC in NMR, ions, nitrogen vacancy (NV) centers,
photons, and superconducting transmons. However, these works primarily
illustrate the signatures or scaling properties of QEC codes rather than test
the capacity of the system to extend the lifetime of quantum information over
time. Here we demonstrate a QEC system that reaches the break-even point by
suppressing the natural errors due to energy loss for a qubit logically encoded
in superpositions of coherent states, or cat states of a superconducting
resonator. Moreover, the experiment implements a full QEC protocol by using
real-time feedback to encode, monitor naturally occurring errors, decode, and
correct. As measured by full process tomography, the enhanced lifetime of the
encoded information is 320 microseconds without any post-selection. This is 20
times greater than that of the system's transmon, over twice as long as an
uncorrected logical encoding, and 10% longer than the highest quality element
of the system (the resonator's 0, 1 Fock states). Our results illustrate the
power of novel, hardware efficient qubit encodings over traditional QEC
schemes. Furthermore, they advance the field of experimental error correction
from confirming the basic concepts to exploring the metrics that drive system
performance and the challenges in implementing a fault-tolerant system.


title:
Derived Kn"orrer periodicity and Orlov's theorem for gauged
  Landau-Ginzburg models

abstract:
  We prove a Kn"orrer periodicity type equivalence between derived
factorization categories of gauged LG models, which is an analogy of a theorem
proved by Shipman and Isik independently. As an application, we obtain a gauged
LG version of Orlov's theorem describing a relationship between categories of
graded matrix factorizations and derived categories of hypersurfaces in
projective spaces, by combining the above Kn"orrer periodicity type equivalence
and the theory of variations of GIT quotients due to Ballard, Favero and
Katzarkov.


title: Stability of densities for perturbed degenerate Diffusions

abstract:
  We study the sensitivity of the densities of some Kolmogorov like degenerate
diffusion processes with respect to a perturbation of the coefficients of the
non-degenerate component. Under suitable (quite sharp) assumptions we quantify
how the pertubation of the SDE affects the density. Natural applications of
these results appear in various fields from mathematical finance to kinetic
models.


title: Analyzing modified unimodular gravity via Lagrange multipliers

abstract:
  The so-called unimodular version of General Relativity is revisited.
Unimodular gravity is constructed by fixing the determinant of the metric, what
leads to the trace-free part of the equations instead of the usual Einstein
field equations. Then, a cosmological constant naturally arises as an
integration constant. While unimodular gravity turns out equivalent to General
Relativity (GR) at the classical level, it provides important differences at
the quantum level. Here we extend the unimodular constraint to some extensions
of General Relativity that have drawn a lot of attention over the last years,
as $f(R)$ gravity (or its scalar-tensor picture) and Gauss-Bonnet gravity. The
corresponding unimodular version of such theories is constructed as well as the
conformal transformation that relates the Einstein and Jordan frames for these
non-minimally coupled theories. From the classical point of view, the
unimodular versions of such extensions are completely equivalent to their
originals, but an effective cosmological constant arises naturally, what may
provide a richer description of the universe evolution. Here we analyze the
case of Starobisnky inflation and compared with the original one.


title: The Kennicutt-Schmidt Relation in Extremely Metal-Poor Dwarf Galaxies

abstract:
  The Kennicutt-Schmidt (KS) relation between the gas mass and star formation
rate (SFR) describes the star formation regulation in disk galaxies. It is a
function of gas metallicity, but the low metallicity regime of the KS diagram
is poorly sampled. We have analyzed data for a representative set of extremely
metal-poor galaxies (XMPs), as well as auxiliary data, and compared these to
empirical and theoretical predictions. The majority of the XMPs possess high
specific SFRs, similar to high redshift star-forming galaxies. On the KS plot,
the XMP HI data occupy the same region as dwarfs, and extend the relation for
low surface brightness galaxies. Considering the HI gas alone, a considerable
fraction of the XMPs already fall off the KS law. Significant quantities of
'dark' H$_2$ mass (i.e., not traced by CO) would imply that XMPs possess low
star formation efficiencies (SFE$_{\rm gas}$). Low SFE$_{\rm gas}$ in XMPs may
be the result of the metal-poor nature of the HI gas. Alternatively, the HI
reservoir may be largely inert, the star formation being dominated by
cosmological accretion. Time lags between gas accretion and star formation may
also reduce the apparent SFE$_{\rm gas}$, as may galaxy winds, which can expel
most of the gas into the intergalactic medium. Hence, on global scales, XMPs
could be HI-dominated, high specific SFR ($\gtrsim $ 10$^{-10}$ yr$^{-1}$), low
SFE$_{\rm gas}$ ($\lesssim$ 10$^{-9}$ yr$^{-1}$) systems, in which the total HI
mass is likely not a good predictor of the total H$_2$ mass nor of the SFR.


title: Competing metabolic strategies in a multilevel selection model

abstract:
  The interplay between energy efficiency and evolutionary mechanisms is
addressed. One important question is how evolutionary mechanisms can select for
the optimised usage of energy in situations where it does not lead to immediate
advantage. For example, this problem is of great importance to improve our
understanding about the major transition from unicellular to multicellular form
of life. The immediate advantage of gathering efficient individuals in an
energetic context is not clear. Although this process increases relatedness
among individuals, it also increases local competition. To address this
question, we propose a model of two competing metabolic strategies that makes
explicit reference to the resource usage. We assume the existence of an
efficient strain, which converts resource into energy at high efficiency but
displays a low rate of resource consumption, and an inefficient strain, which
consumes resource at a high rate with a low efficiency in converting it to
energy. We explore the dynamics in both well-mixed and structured populations.
The selection for optimised energy usage is measured by the likelihood of that
an efficient strain can invade a population only comprised by inefficient
strains. It is found that the region of the parameter space at which the
efficient strain can thrive in structured populations is always larger than
observed in well-mixed populations. In fact, in well-mixed populations the
efficient strain is only evolutionarily stable in the domain whereupon there is
no evolutionary dilemma. We also observe that small group sizes enhance the
chance of invasion by the efficient strain in spite of increasing the
competition among relatives. This outcome corroborates the key role played by
kin selection and shows that the group dynamics relied on group expansion,
overlapping generations and group split can balance the negative effects of
local competition.


title: Survival of weak-field seekers inside a TOP trap

abstract:
  In this article, for the first time in the context of TOP trap, the necessary
and sufficient conditions for the adiabatic evolution of weak field seeking
states have been quantitatively examined. It has been well accepted since
decades that adiabaticity has to be obeyed by the atoms for successful magnetic
trapping. However, we show, on the contrary, that atoms can also be confined
beyond the adiabatic limit. Hence, our findings open new possibilities to relax
the restrictions of atom trapping in laboratories.


title:
Alignment of interstellar grains by mechanical torques: suprathermally
  rotating Gaussian random spheres

abstract:
  Collisions of gas particles with a drifting grain give rise to a mechanical
torque on the grain. Recent work by Lazarian & Hoang showed that mechanical
torques might play a significant role in aligning helical grains along the
interstellar magnetic field direction, even in the case of subsonic drift. We
compute the mechanical torques on 13 different irregular grains and examine
their resulting rotational dynamics, assuming steady rotation about the
principal axis of greatest moment of inertia. We find that the alignment
efficiency in the subsonic drift regime depends sensitively on the grain shape,
with more efficient alignment for shapes with a substantial mechanical torque
even in the case of no drift. The alignment is typically more efficient for
supersonic drift. A more rigorous analysis of the dynamics is required to
definitively appraise the role of mechanical torques in grain alignment.


title:
Parameterizable Consensus Connectomes from the Human Connectome Project:
  The Budapest Reference Connectome Server v3.0

abstract:
  Connections of the living human brain, on a macroscopic scale, can be mapped
by a diffusion MR imaging based workflow. Since the same anatomic regions can
be corresponded between distinct brains, one can compare the presence or the
absence of the edges, connecting the very same two anatomic regions, among
multiple cortices. Previously, we have constructed the consensus braingraphs on
1015 vertices first in five, then in 96 subjects in the Budapest Reference
Connectome Server v1.0 and v2.0, respectively. Here we report the construction
of the version 3.0 of the server, generating the common edges of the
connectomes of variously parameterizable subsets of the 1015-vertex connectomes
of 477 subjects of the Human Connectome Project's 500-subject release. The
consensus connectomes are downloadable in csv and GraphML formats, and they are
also visualized on the server's page. The consensus connectomes of the server
can be considered as the "average, healthy" human connectome since all of their
connections are present in at least $k$ subjects, where the default value of
$k=209$, but it can also be modified freely at the web server. The webserver is
available at \url{http://connectome.pitgroup.org}.


title: Schur polynomials and matrix positivity preservers

abstract:
  A classical result by Schoenberg (1942) identifies all real-valued functions
that preserve positive semidefiniteness (psd) when applied entrywise to
matrices of arbitrary dimension. Schoenberg's work has continued to attract
significant interest, including renewed recent attention due to applications in
high-dimensional statistics. However, despite a great deal of effort in the
area, an effective characterization of entrywise functions preserving
positivity in a fixed dimension remains elusive to date. As a first step, we
characterize new classes of polynomials preserving positivity in fixed
dimension. The proof of our main result is representation theoretic, and
employs Schur polynomials. An alternate, variational approach also leads to
several interesting consequences including (a) a hitherto unexplored Schubert
cell-type stratification of the cone of psd matrices, (b) new connections
between generalized Rayleigh quotients of Hadamard powers and Schur
polynomials, and (c) a description of the joint kernels of Hadamard powers.


title: Leinert sets and complemented ideals in Fourier algebras

abstract:
  Let $G$ be a locally compact group. We show how complemented ideals in the
Fourier algebra $A(G)$ of $G$ arise naturally from a class of thin sets known
as Leinert sets. Moreover, we also present an explicit example of a closed
ideal in $A(\mathbb{F}_{N})$, the free group on $N \ge 2$ generators, that is
complemented in $A(\mathbb{F}_{N})$ but it is not completely complemented. Then
by establishing an appropriate extension result for restriction algebras
arising from Leinert sets, we show that any almost connected group $G$ for
which every complemented ideal in $A(G)$ is also completely complemented must
be amenable.


title:
Constraints on frequency-dependent violations of Shapiro delay from
  GW150914

abstract:
  On 14th September 2015, a transient gravitational wave (GW150914) was
detected by the two LIGO detectors at Hanford and Livingston from the
coalescence of a binary black hole system located at a distance of about 400
Mpc. We point out that GW150914 experienced a Shapiro delay due to the
gravitational potential of the mass distribution along the line of sight of
about 1800 days. Also, the near-simultaneous arrival of gravitons over a
frequency range of about 100 Hz within a 0.2 second window allows us to
constrain any violations of Shapiro delay and Einstein's equivalence principle
between the gravitons at different frequencies. From the calculated Shapiro
delay and the observed duration of the signal, frequency-dependent violations
of the equivalence principle for gravitons are constrained to an accuracy of
$\mathcal{O}(10^{-9})$


title: Superconducting properties of tin-copper amorphous thin films

abstract:
  The thermodynamic properties of the superconducting state in the amorphous
${\rm Sn_{1-x}Cu_{x}}$ thin films have been characterized. The concentration of
copper changes in the range from $0.08$ to $0.41$. The calculations have been
conducted in the framework of the strong-coupling formalism, wherein the
Eliashberg functions determined in the tunnel experiment (Phys. Rev. B {\bf
51}, 685 (1995)) have been used. The value of the Coulomb pseudopotential equal
to $0.1$ has been adopted. It has been found that the critical temperature
($T_{C}$) decreases from $7$ K to $3.9$ K. The ratio of the energy gap to the
critical temperature: $R_{\Delta}=2\Delta\left(0\right)/k_{B}T_{C}$, differs
significantly from the BCS value: $R_{\Delta}\in\left<4.4,3.95\right>$.
Similarly behaves the ratio of the specific heat jump to the specific heat of
the normal state: $R_{C}=\Delta C\left(T_{C}\right)/C^{N}\left(T_{C}\right)$,
and the parameter:
$R_{H}=T_{C}C^{N}\left(T_{C}\right)/H^{2}_{C}\left(0\right)$, where
$H_{C}\left(0\right)$ is the thermodynamic critical field. In particular,
$R_{C}\in\left<2.2,1.75\right>$ and $R_{H}\in\left<0.141,0.154\right>$.


title: On Alternation and the Union Theorem

abstract:
  Under the assumption $P=\Sigma_2^p$, we prove a new variant of the Union
Theorem of McCreight and Meyer for the class $\Sigma_2^p$. This yields a union
function $F$ which is computable in time $F(n)^c$ for some constant $c$ and
satisfies $P=DTIME(F)=\Sigma_2(F)=\Sigma_2^p$ with respect to a subfamily
$(\tilde{S}_i)$ of $\Sigma_2$-machines. We show that this subfamily does not
change the complexity classes $P$ and $\Sigma_2^p$. Moreover, a padding
construction shows that this also implies $DTIME(F^c)=\Sigma_2(F^c)$. On the
other hand, we prove a variant of Gupta's result who showed that
$DTIME(t)\subsetneq\Sigma_2(t)$ for time-constructible functions $t(n)$. Our
variant of this result holds with respect to the subfamily $(\tilde{S}_i)$ of
$\Sigma_2$-machines. We show that these two results contradict each other.
Hence the assumption $P=\Sigma_2^p$ cannot hold.


title: Testing local Lorentz invariance with gravitational waves

abstract:
  The effects of local Lorentz violation on dispersion and birefringence of
gravitational waves are investigated. The covariant dispersion relation for
gravitational waves involving gauge-invariant Lorentz-violating operators of
arbitrary mass dimension is constructed. The chirp signal from the
gravitational-wave event GW150914 is used to place numerous first constraints
on gravitational Lorentz violation.


title: Parrondo's Paradox: some new results and new ideas

abstract:
  Parrondo's paradox is about a paradoxical game and gambling where two
probabilistic losing games can be combined to form a winning game. While the
counter intuitive game is interesting in itself, it can be thought of a
discrete version of Brownian flashing ratchet which are employed to understand
noise induced order. There are plenty of examples from physics to biology and
social sciences where the stochastic thermal fluctuations actually help
achieving positive movements. In our study, we study various combinations of
losing games in order to understand how and how far the losing combinations
result in winning. Further we devise an alternative model to study the similar
paradox. The work reported here is mostly done through computer simulations.


title:
Notes on the Discontinuous Galerkin methods for the numerical simulation
  of hyperbolic equations 1 General Context 1.1 Bibliography

abstract:
  The roots of Discontinuous Galerkin (DG) methods is usually attributed to
Reed and Hills in a paper published in 1973 on the numerical approximation of
the neutron transport equation [18]. In fact, the adventure really started with
a rather thoroughfull series of five papers by Cockburn and Shu in the late
80's [7, 5, 9, 6, 8]. Then, the fame of the method, which could be seen as a
compromise between Finite Elements (the center of the method being a weak
formulation) and Finite Volumes (the basis functions are defined cell-wise, the
cells being the elements of the primal mesh) increased and slowly investigated
successfully all the domains of Partial Differential Equations numerical
integration. In particular, one can cite the ground papers for the common
treatment of convection-diffusion equations [4, 3] or the treatment of pure
elliptic equations [2, 17]. For more information on the history of
Discontinuous Galerkin method, please refer to section 1.1 of [15]. Today, DG
methods are widely used in all kind of manners and have applications in almost
all fields of applied mathematics. (TODO: cite applications and
structured/unstructured meshes, steady/unsteady, etc...). The methods is now
mature enough to deserve entire text books, among which I cite a reference book
on Nodal DG Methods by Henthaven and Warburton [15] with the ground basis of DG
integration, numerical analysis of its linear behavior and generalization to
multiple dimensions. Lately, since 2010, thanks to a ground work of Zhang and
Shu [26, 27, 25, 28, 29], Discontinuous Galerkin methods are eventually able to
combine high order accuracy and certain preservation of convex constraints,
such as the positivity of a given quantity, for example. These new steps
forward are very promising since it brings us very close to the "Ultimate
Conservative Scheme", [23, 1].


title: Approximate solutions of continuous-time stochastic games

abstract:
  The paper is concerned with a zero-sum continuous-time stochastic
differential game with a dynamics controlled by a Markov process and a terminal
payoff. The value function of the original game is estimated using the value
function of a model game. The dynamics of the model game differs from the
original one. The general result applied to differential games yields the
approximation of value function of differential game by the solution of
countable system of ODEs.


title:
A Static Cosmological Model Based on the Group of Conservative
  Transformations

abstract:
  The group of Conservative transformations is an enlargement of the group of
diffeomorphisms which leads to a richer geometry than that of general
relativity. The field variables of the theory are the usual orthonormal tetrads
and also internal space tetrads. Using the fundamental geometric object which
is the curvature vector, an appropriate Lagrangian has been defined for both
free-field and fields with sources. Solutions to the corresponding field
equations have been developed. In this paper we use the static spherically
symmetric tetrad field with sources to model the universe. Our fundamental
assumption is that the total density comprised of both ordinary and dark matter
should be constant. The resulting model with one adjustable parameter predicts
that ordinary matter is approximately 77\% of the total mass content, but this
percentage is near 0\% for regions near the center of the universe. The space
is approximately isotropic for $r$ near zero. The radial and tangential
pressures are negative and unequal. The redshift is also modeled without the
expanding universe and an explanation of the value of the cosmological constant
is given. Equations governing particle motion are also derived which can
produce a repulsive effect and produce even larger redshifts. Finally, the
cosmic microwave background and its anisotropies are addressed and heuristic
arguments are given that suggest that our theory is not inconsistent with these
observations. These results add further confirmation that the theory developed
by Pandres is the fundamental theory of physics.


title: A `fast-burning' mechanism for magnetic diffusion

abstract:
  Fast-burning mechanism describes the rapid penetration, with a sharp-shaped
wave-front, of a strong magnetic field into a conductive metal whose electric
resistance poses an abrupt rise at some critical temperature. With its
wave-front sweeping over a solid metal, the fast-burning can melt or vaporize
the metal very rapidly. This paper derives formulas for the existence
conditions and wave-front velocity of a fast-burning.


title:
The $\textit{Fermi}$-LAT gamma-ray excess at the Galactic Center in the
  singlet-doublet fermion dark matter model

abstract:
  The singlet-doublet fermion dark matter model (SDFDM) provides a good DM
candidate as well as the possibility of generating neutrino masses radiatively.
The search and identification of DM requires the combined effort of both
indirect and direct DM detection experiments in addition to the LHC.
Remarkably, an excess of GeV gamma rays from the Galactic Center (GCE) has been
measured with the \textit{Fermi} Large Area Telescope (LAT) which appears to be
robust with respect to changes in the diffuse galactic background modeling.
Although several astrophysical explanations have been proposed, DM remains a
simple and well motivated alternative. In this work, we examine the
sensitivities of dark matter searches in the SDFDM scenario using
$\textit{Fermi}$-LAT, CTA, IceCube/DeepCore, LUX, PICO and LHC with an emphasis
on exploring the regions of the parameter space that can account for the GCE.
We find that DM particles present in this model with masses close to $\sim 99$
GeV and $\sim (173-190)$ GeV annihilating predominantly into the $W^+W^-$
channel and $t\bar{t}$ channel respectively, provide an acceptable fit to the
GCE while being consistent with different current experimental bounds. We also
find that much of the obtained parameter space can be ruled out by future
direct search experiments like LZ and XENON-1T, in case of null results by
these detectors. Interestingly, we show that the most recent data by LUX is
starting to probe the best fit region in the SDFDM model.


title: Fourier extension for extremal quadratic submanifolds

abstract:
  This note establishes the full range of $L^p$--$L^q$ Fourier extension
estimates for the model $n$-dimensional quadratic submanifold in ${\mathbb
R}^{n(n+3)/2}$ parametrized by $\gamma(x_1,\ldots,x_n) := (x_1,\ldots,x_n, (x_i
x_j)_{1 \leq i \leq j \leq n})$. This class of submanifolds is extremal in the
sense that an $n$-dimensional quadratic submanifold of ${\mathbb R}^d$ can only
satisfy nontrivial Fourier extension inequalities when $d \leq
\frac{n(n+3)}{2}$. The proof is via an inflation-type argument, with the
unexpected twist that a significant amount of "overinflation" is necessary but
in no way limits the sharpness of the argument.


title: Differentiation on spaces of triangulations and optimized triangulations

abstract:
  We describe a smooth structure, called Fr\"olicher space, on CW complexes and
spaces of triangulations. This structure enables differential methods for e.g.
minimization of functionnals. As an application, we exhibit how an optimized
triangulation can be obtained in order to solve a standard PDE.


title: Some Properties of the Derivatives on Sierpinski Gasket Type Fractals

abstract:
  In this paper, we focus on Strichartz's derivatives, a family of derivatives
including the normal derivative, on p.c.f. (post critically finite) fractals,
which are defined at vertex points in the graphs that approximate the fractal.
We obtain a weak continuity property of the derivatives for functions in the
domain of the Laplacian. For a function with zero normal derivative at any
fixed vertex, the derivatives, including the normal derivatives of the
neighboring vertices will decay to zero. The optimal rates of approximations
are described and several non-trivial examples are provided to illustrate that
our estimates are sharp. We also study the boundness property of derivatives
for functions in the domain of the Laplacian. A necessary condition for a
function having a weak tangent of order one at a vertex point is provided.
Furthermore, we give a counter-example of a conjecture of Strichartz on the
existence of higher order weak tangents.


title:
Preference Elicitation in Matching Markets via Interviews: A Study of
  Offline Benchmarks

abstract:
  The stable marriage problem and its extensions have been extensively studied,
with much of the work in the literature assuming that agents fully know their
own preferences over alternatives. This assumption however is not always
practical (especially in large markets) and agents usually need to go through
some costly deliberation process in order to learn their preferences. In this
paper we assume that such deliberations are carried out via interviews, where
an interview involves a man and a woman, each of whom learns information about
the other as a consequence. If everybody interviews everyone else, then clearly
agents can fully learn their preferences. But interviews are costly, and we may
wish to minimize their use. It is often the case, especially in practical
settings, that due to correlation between agents' preferences, it is
unnecessary for all potential interviews to be carried out in order to obtain a
stable matching. Thus the problem is to find a good strategy for interviews to
be carried out in order to minimize their use, whilst leading to a stable
matching. One way to evaluate the performance of an interview strategy is to
compare it against a naive algorithm that conducts all interviews. We argue
however that a more meaningful comparison would be against an optimal offline
algorithm that has access to agents' preference orderings under complete
information. We show that, unless P=NP, no offline algorithm can compute the
optimal interview strategy in polynomial time. If we are additionally aiming
for a particular stable matching (perhaps one with certain desirable
properties), we provide restricted settings under which efficient optimal
offline algorithms exist.


title: Bands in the spectrum of a periodic elastic waveguide

abstract:
  We study the spectral linear elasticity problem in an unbounded periodic
waveguide, which consists of a sequence of identical bounded cells connected by
thin ligaments of diameter of order $ h >0$. The essential spectrum of the
problem is known to have band-gap structure. We derive asymptotic formulas for
the position of the spectral bands and gaps, as $h \to 0$.


title:
The Spectacular Radio-Near-IR-X-ray Jet of 3C 111: X-ray Emission
  Mechanism and Jet Kinematics

abstract:
  Relativistic jets are the most energetic manifestation of the active galactic
nucleus (AGN) phenomenon. AGN jets are observed from the radio through
gamma-rays and carry copious amounts of matter and energy from the sub-parsec
central regions out to the kiloparsec and often megaparsec scale galaxy and
cluster environs. While most spatially resolved jets are seen in the radio, an
increasing number have been discovered to emit in the optical/near-IR and/or
X-ray bands. Here we discuss a spectacular example of this class, the 3C 111
jet, housed in one of the nearest, double-lobed FR II radio galaxies known. We
discuss new, deep Chandra and HST observations that reveal both near-IR and
X-ray emission from several components of the 3C 111 jet, as well as both the
northern and southern hotspots. Important differences are seen between the
morphologies in the radio, X-ray and near-IR bands. The long (over 100 kpc on
each side), straight nature of this jet makes it an excellent prototype for
future, deep observations, as it is one of the longest such features seen in
the radio, near-IR/optical and X-ray bands. Several independent lines of
evidence, including the X-ray and broadband spectral shape as well as the
implied velocity of the approaching hotspot, lead us to strongly disfavor the
EC/CMB model and instead favor a two-component synchrotron model to explain the
observed X-ray emission for several jet components. Future observations with
NuSTAR, HST, and Chandra will allow us to further constrain the emission
mechanisms.


title:
Asymptotics of scalar waves on long-range asymptotically Minkowski
  spaces

abstract:
  We show the existence of the full compound asymptotics of solutions to the
scalar wave equation on long-range non-trapping Lorentzian manifolds modeled on
the radial compactification of Minkowski space. In particular, we show that
there is a joint asymptotic expansion at null and timelike infinity for forward
solutions of the inhomogeneous equation. In two appendices we show how these
results apply to certain spacetimes whose null infinity is modeled on that of
the Kerr family. In these cases the leading order logarithmic term in our
asymptotic expansions at null infinity is shown to be nonzero.


title:
Comment on "Constant stress and pressure rheology of colloidal
  suspensions"

abstract:
  This is a comment on the recent letter by Wang and Brady on "Constant stress
and pressure rheology of colloidal suspensions", Phys. Rev. Lett. 115, 158301
(2015).


title: Finite Groups with Odd Sylow Normalizers

abstract:
  We determine the non-abelian composition factors of the finite groups with
Sylow normalizers of odd order. As a consequence, among others, we prove the
McKay conjecture and the Alperin weight conjecture for these groups.


title:
Color-superconductivity and inhomogeneous chiral symmetry breaking in
  isospin-asymmetric quark matter

abstract:
  We investigate the effects of isospin asymmetry on the competition between
color-superconductivity and inhomogeneous chiral symmetry breaking in dense
two-flavor quark matter using an extended Nambu--Jona-Lasinio model. We confirm
the appearance of a coexistence window where chiral symmetry is inhomogeneously
broken and a nonzero spatially homogeneous diquark gap is present, consistently
with previous works, and show that such a phase survives at nonzero isospin
chemical potentials. We also discuss how the model phase structure becomes
modified as large isospin asymmetries are considered.


title: Quantum Perceptron Models

abstract:
  We demonstrate how quantum computation can provide non-trivial improvements
in the computational and statistical complexity of the perceptron model. We
develop two quantum algorithms for perceptron learning. The first algorithm
exploits quantum information processing to determine a separating hyperplane
using a number of steps sublinear in the number of data points $N$, namely
$O(\sqrt{N})$. The second algorithm illustrates how the classical mistake bound
of $O(\frac{1}{\gamma^2})$ can be further improved to
$O(\frac{1}{\sqrt{\gamma}})$ through quantum means, where $\gamma$ denotes the
margin. Such improvements are achieved through the application of quantum
amplitude amplification to the version space interpretation of the perceptron
model.


title: Reduced Complexity Multi-Scale Path-Planning on Probabilistic Maps

abstract:
  We present several modifications to the previously proposed MSPP algorithm
that can speed-up its execution considerably. The MSPP algorithm leverages a
multiscale representation of the environment in $n$ dimensions. The information
of the environment is stored in a tree data structure representing a recursive
dyadic partitioning of the search space. The information used by the algorithm
is the probability that a node in the tree corresponds to an obstacle in the
search space. Such trees are often created from mainstream perception
algorithms, and correspond to quadtrees and octrees in two and three
dimensions, respectively. We first present a new method to compute the graph
neighbors in order to reduce the complexity of each iteration, from $O(| V|^2)$
to $O(| V| \log |V|)$. We then show how to delay expensive intermediate
computations until we know that new information will be required, hence saving
time by not operating on information that is never used during the search.
Finally, we present a way to remove the very expensive need to calculate a full
multi-scale map with the use of sampling and derive an theoretical upperbound
of the probability of failure as a function of the number of samples.


title:
Precision Drell-Yan Measurements at the LHC and Implications for the
  Diphoton Excess

abstract:
  Precision measurements of the Drell-Yan (DY) cross section at the LHC
constrain new physics scenarios that involve new states with electroweak (EW)
charges. We analyze these constraints and apply them to models that can address
the LHC diphoton excess at 750 GeV. We confront these findings with LEP EW
precision tests and show that DY provides stronger constraints than the LEP
data. While 8 TeV data can already probe some parts of the interesting region
of parameter space, LHC14 results are expected to cover a substantial part of
the relevant terrain. We derive the bounds from the existing data, estimate
LHC14 reach and compare them to the bounds one gets from LEP and future FCC-ee
precision measurements.


title: Emergent Conformal Symmetry of Quantum Hall States on Singular surfaces

abstract:
  We show that quantum Hall states on surfaces with conical singularities
behave as conformal primaries near the singular points, with a conformal
dimension controlled by the gravitational anomaly. We show that the electronic
fluid at the cone tip possesses an intrinsic angular momentum equal to the
conformal dimension, in units of the Planck constant. Finally, we argue that
the gravitational anomaly also controls { the fine structure of electronic
density at the tip, and } the exchange statistics of cones in the Laughlin
states, arising from adiabatically braiding conical singularities. Thus, the
gravitational anomaly, which appears as a finite size correction on smooth
surfaces, dominates geometric transport on singular surfaces.


title:
Single-quanta interferometry: which-way versus which-phase information
  stored in an ancillary quantum system

abstract:
  In interferometers, the more information about the quanta's path available in
an ancillary quantum system (AQS), the less visibility the interference has. By
use of Shannon entropy, we try to compare the amount of which-phase information
with the amount of which-way information stored in the AQS of two-path
interferometers with symmetric beam merging. We show that the former is lower
than or equal the latter if the bipartite system of the single-quanta and the
AQS is initially prepared in a pure state and the interaction between the two
parts is unitary. Especially when there exists symmetry, the equality holds. No
which-way information is obtained by the measurement that we use for extracting
the which-phase information and vice versa. In order to verify the results
experimentally, we propose assembling a new single-photon interferometer.


title:
Classification of topological phases in periodically driven interacting
  systems

abstract:
  We consider topological phases in periodically driven (Floquet) systems
exhibiting many-body localization, protected by a symmetry $G$. We argue for a
general correspondence between such phases and topological phases of undriven
systems protected by symmetry $\mathbb{Z} \rtimes G$, where the additional
$\mathbb{Z}$ accounts for the discrete time translation symmetry. Thus, for
example, the bosonic phases in $d$ spatial dimensions without intrinsic
topological order (SPT phases) are classified by the cohomology group
$H^{d+1}(\mathbb{Z} \rtimes G, \mathrm{U}(1))$. For unitary symmetries, we
interpret the additional resulting Floquet phases in terms of the
lower-dimensional SPT phases that are pumped to the boundary during one time
step. These results also imply the existence of novel symmetry-enriched
topological (SET) orders protected solely by the periodicity of the drive.

categories: cond-mat.str-el cond-mat.dis-nn cond-mat.stat-mech quant-ph


title:
DR-ABC: Approximate Bayesian Computation with Kernel-Based Distribution
  Regression

abstract:
  Performing exact posterior inference in complex generative models is often
difficult or impossible due to an expensive to evaluate or intractable
likelihood function. Approximate Bayesian computation (ABC) is an inference
framework that constructs an approximation to the true likelihood based on the
similarity between the observed and simulated data as measured by a predefined
set of summary statistics. Although the choice of appropriate problem-specific
summary statistics crucially influences the quality of the likelihood
approximation and hence also the quality of the posterior sample in ABC, there
are only few principled general-purpose approaches to the selection or
construction of such summary statistics. In this paper, we develop a novel
framework for this task using kernel-based distribution regression. We model
the functional relationship between data distributions and the optimal choice
(with respect to a loss function) of summary statistics using kernel-based
distribution regression. We show that our approach can be implemented in a
computationally and statistically efficient way using the random Fourier
features framework for large-scale kernel learning. In addition to that, our
framework shows superior performance when compared to related methods on toy
and real-world problems.


title:
State Space Analysis of Memristor Based Series and Parallel RLCM
  Circuits

abstract:
  The present paper investigates state space analysis of memristor based series
and parallel RLCM circuits. The stability analysis is carried out with the help
of eigenvalues formulation method, pole-zero plot and transient response of
system. The state space analysis is successfully applied and eigenvalues of the
two circuits are calculated. It is found that the, system follows negative real
part of eigenvalues. The result clearly shows that addition of memristor in
circuits will not alter the stability of system. It is found that systems poles
located at left hand side of the S plane, which indicates stable performance of
system. It clearly evident that eigenvalues has negative real part hence two
systems are internally stable.


title: Woronowicz's Tannaka-Krein duality and free orthogonal quantum groups

abstract:
  Given a finite dimensional Hilbert space H and a collection of operators
between its tensor powers satisfying certain properties, we give a
category-free proof of the existence of a compact quantum group G with a
fundamental representation U on H such that the intertwiners between the tensor
powers of U coincide with the given collection of operators. We then explain
how the general version of Woronowicz's Tannaka-Krein duality can be deduced
from this.


title: Optimal Composition of Modal Currents For Minimal Quality Factor Q

abstract:
  This work describes a powerful, yet simple, procedure how to acquire a
current approaching the lower bound of quality factor Q. This optimal current
can be determined for an arbitrarily shaped electrically small radiator made of
a perfect conductor. Quality factor Q is evaluated by Vandenbosch's relations
yielding stored electromagnetic energy as a function of the source current
density. All calculations are based on a matrix representation of the
integro-differential operators. This approach simplifies the entire development
and results in a straightforward numerical evaluation. The optimal current is
represented in a basis of modal currents suitable for solving the optimization
problem so that the minimum is approached by either one mode tuned to the
resonance, or, by two properly combined modes. An overview of which modes
should be selected and how they should be combined is provided and results
concerning rectangular plate, spherical shell and fractal shapes of varying
geometrical complexity are presented. The reduction of quality factor Q and the
G/Q ratio are studied and, thanks to the modal decomposition, the physical
interpretation of the results is discussed in conjunction with the limitations
of the proposed procedure.