title: Temporal Chiral Spiral in Strong Magnetic Fields

abstract:
  Vacuum properties of quantum chromodynamics in strong magnetic and finite
electric fields are investigated. We show that when a uniform electric field is
instantaneously applied in the parallel direction to a strong magnetic field,
it induces temporal oscillation of the chiral and pion condensates. This is a
temporal analog to the chiral spiral. The oscillation originates with the
propagation of the collective mode, which is protected by the axial anomaly and
thus nondissipative.


title:
A Ten Billion Solar Mass Outflow of Molecular Gas Launched by Radio
  Bubbles in the Abell 1835 Brightest Cluster Galaxy

abstract:
  We report ALMA Early Science observations of the Abell 1835 brightest cluster
galaxy (BCG) in the CO (3-2) and CO (1-0) emission lines. We detect 5E10 solar
masses of molecular gas within 10 kpc of the BCG. Its velocity width of ~130
km/s FWHM is too narrow to be supported by dynamical pressure. The gas may
instead be supported in a rotating, turbulent disk oriented nearly face-on. The
disk is forming stars at a rate of 100-180 solar masses per year. Roughly 1E10
solar masses of molecular gas is projected 3-10 kpc to the north-west and to
the east of the nucleus with line of sight velocities lying between -250 km/s
to +480 km/s with respect to the systemic velocity. Although inflow cannot be
ruled out, the rising velocity gradient with radius is consistent with a broad,
bipolar outflow driven by radio jets or buoyantly rising X-ray cavities. The
molecular outflow may be associated with an outflow of hot gas in Abell 1835
seen on larger scales. Molecular gas is flowing out of the BCG at a rate of
approximately 200 solar masses per year, which is comparable to its star
formation rate. How radio bubbles lift dense molecular gas in their updrafts,
how much gas will be lost to the BCG, and how much will return to fuel future
star formation and AGN activity are poorly understood. Our results imply that
radio-mechanical (radio mode) feedback not only heats hot atmospheres
surrounding elliptical galaxies and BCGs, it is able to sweep higher density
molecular gas away from their centers.


title: Massive molecular gas flows in the Abell 1664 brightest cluster galaxy

abstract:
  We report ALMA Early Science CO(1-0) and CO(3-2) observations of the
brightest cluster galaxy (BCG) in Abell 1664. The BCG contains 1.1x10^{10}
solar masses of molecular gas divided roughly equally between two distinct
velocity systems: one from -250 to +250 km/s centred on the BCG's systemic
velocity and a high velocity system blueshifted by 570 km/s with respect to the
systemic velocity. The BCG's systemic component shows a smooth velocity
gradient across the BCG center with velocity proportional to radius suggestive
of solid body rotation about the nucleus. However, the mass and velocity
structure are highly asymmetric and there is little star formation coincident
with a putative disk. It may be an inflow of gas that will settle into a disk
over several 10^8 yr. The high velocity system consists of two gas clumps, each
~2 kpc across, located to the north and southeast of the nucleus. Each has a
line of sight velocity spread of 250-300 km/s. The velocity of the gas in the
high velocity system tends to increase towards the BCG center and could signify
a massive high velocity flow onto the nucleus. However, the velocity gradient
is not smooth and these structures are also coincident with low optical-UV
surface brightness regions, which could indicate dust extinction associated
with each clump. If so, the high velocity gas would be projected in front of
the BCG and moving toward us along the line of sight in a massive outflow most
likely driven by the AGN. A merger origin is unlikely but cannot be ruled out.


title:
Bottom-up superconducting and Josephson junction devices inside a
  group-IV semiconductor

abstract:
  Superconducting circuits are exceptionally flexible, enabling many different
devices from sensors to quantum computers. Separately, epitaxial semiconductor
devices such as spin qubits in silicon offer more limited device variation but
extraordinary quantum properties for a solid-state system. It might be possible
to merge the two approaches, making single-crystal superconducting devices out
of a semiconductor by utilizing the latest atomistic fabrication techniques.
Here we propose superconducting devices made from precision hole-doped regions
within a silicon (or germanium) single crystal. We analyze the properties of
this superconducting semiconductor and show that practical superconducting
wires, Josephson tunnel junctions or weak links, superconducting quantum
interference devices (SQUIDs), and qubits are feasible. This work motivates the
pursuit of "bottom-up" superconductivity for improved or fundamentally
different technology and physics.


title:
Magnetocapacitance as a sensitive probe of magnetostructural changes in
  NiCr$_2$O$_4$

abstract:
  The spinel NiCr$_2$O$_4$ is characterized using dielectric and high magnetic
field measurements. The trends in the magnetodielectric response fall into
three clear temperature regimes corresponding to known magnetic and structural
transitions. Above 65\,K, weak magnetic field dependence of the dielectric
constant is observed with no hysteresis. When 30\,K\,$\leq\,T\,\leq$\,65\,K, a
strong dependence of the dielectric constant on the magnetic field is observed
and hysteresis develops resulting in so called butterfly loops. Below 30\,K,
magnetodielectric hysteresis is enhanced. Magnetodielectric hysteresis mirrors
magnetic hysteresis suggesting that spin-spin interactions are the mechanism
for the magnetoelectric effect in NiCr$_2$O$_4$. At high fields however, the
magnetization continues to increase while the dielectric constant saturates.
Magnetodielectric measurements of NiCr$_2$O$_4$ suggest an additional,
previously unobserved transition at 20\,K. Subtle changes in magnetism and
structure suggest that this 20\,K anomaly corresponds to the completion of
ferrimagnetic ordering and the spin driven structural distortion. We
demonstrate that magnetocapacitance is a sensitive probe of magnetostructural
distortion.


title: NNLOPS simulation of Higgs boson production

abstract:
  We detail a simulation of Higgs boson production via gluon fusion, accurate
at next-to-next-to-leading order in the strong coupling, including matching to
a parton shower, yielding a fully exclusive, hadron-level description of the
final-state. The approach relies on the POWHEG method for merging the NLO Higgs
plus jet cross-section with the parton shower, and on the MINLO method to
simultaneously achieve NLO accuracy for inclusive Higgs boson production. The
NNLO accuracy is reached by a reweighting procedure making use of the HNNLO
program.


title:
Radionuclide Ionization in Protoplanetary Disks: Calculations of Decay
  Product Radiative Transfer

abstract:
  We present simple analytic solutions for the ionization rate
$\zeta_{\rm{SLR}}$ arising from the decay of short-lived radionuclides (SLRs)
within protoplanetary disks. We solve the radiative transfer problem for the
decay products within the disk, and thereby allow for the loss of radiation at
low disk surface densities; energy loss becomes important outside $R\gtrsim30$
for typical disk masses $M_g=0.04$ M$_\odot$. Previous studies of
chemistry/physics in these disks have neglected the impact of ionization by
SLRs, and often consider only cosmic rays (CRs), because of the high CR-rate
present in the ISM. However, recent work suggests that the flux of CRs present
in the circumstellar environment could be substantially reduced by relatively
modest stellar winds, resulting in severely modulated CR ionization rates,
$\zeta_{\rm{CR}}$, equal to or substantially below that of SLRs
($\zeta_{\rm{SLR}}\lesssim10^{-18}$ s$^{-1}$). We compute the net ionizing
particle fluxes and corresponding ionization rates as a function of position
within the disk for a variety of disk models. The resulting expressions are
especially simple for the case of vertically gaussian disks (frequently assumed
in the literature). Finally, we provide a power-law fit to the ionization rate
in the midplane as a function of gas disk surface density and time. Depending
on location in the disk, the ionization rates by SLRs are typically in the
range $\zeta_{\rm{SLR}}\sim(1-10)\times10^{-19}$ s$^{-1}$.


title: The Breuil--Mezard conjecture for quaternion algebras

abstract:
  We formulate a version of the Breuil--Mezard conjecture for quaternion
algebras, and show that it follows from the Breuil--Mezard conjecture for GL_2.
In the course of the proof we establish a mod p analogue of the
Jacquet--Langlands correspondence for representations of GL_2(k), k a finite
field of characteristic p.


title:
Cogeneration of Dark Matter and Baryons by Non-Standard-Model Sphalerons
  in Unified Models

abstract:
  Sphalerons of a new gauge interaction can convert a primordial asymmetry in B
or L into a dark matter asymmetry. From the equilibrium conditions for the
sphalerons of both the electroweak and the new interactions, one can compute
the ratios of B, L, and X, where X is the dark matter number, thus determining
the mass of the dark matter particle fairly precisely. Such a scenario can
arise naturally in the context of unification with larger groups. An
illustrative model embeddable in $SU(6) \times SU(2) \subset E_6$ is described
as well as an equally simple model based on SU(7).


title:
Exotic Higgs Decay h to 2a at the International Linear Collider: a
  Snowmass White Paper

abstract:
  A Higgs factory like the International Linear Collider (ILC) can play a
significant role in searching for exotic decays of Higgs bosons. As an
illustration, we investigate the ILC sensitivity for the decay topology $h\to
a_1 a_1 \to \tau\bar \tau\tau \bar \tau$ in the
Next-to-Minimal-Supersymmetric-Standard-Model (NMSSM). Here $h$ can be either
Standard-Model-like or non-standard, and $a_{1}$ is the lightest CP-odd Higgs
boson. We also compare results to expectations for this channel at the LHC.


title:
Scaling in Modeling of Core Losses in Soft Magnetic Materials Exposed to
  Nonsinusoidal Flux Waveforms and DC Bias

abstract:
  Assuming that core loss data of Soft Magnetic Materials obey scaling
relations, models describing the power losses in materials exposed to
non-sinusoidal flux waveforms and DC Bias conditions have been derived. In
order to test these models, the measurement data for two materials have been
collected and the core losses calculated. Agreement between the experimental
data and the model predictions is satisfactory.


title: Arrays of open, independently tunable microcavities

abstract:
  Optical cavities are of central importance in numerous areas of physics,
including precision measurement, cavity optomechanics and cavity quantum
electrodynamics. The miniaturisation and scaling to large numbers of sites is
of interest for many of these applications, in particular for quantum
computation and simulation. Here we present the first scaled microcavity system
which enables the creation of large numbers of highly uniform, tunable
light-matter interfaces using ions, neutral atoms or solid-state qubits. The
microcavities are created by means of silicon micro-fabrication, are coupled
directly to optical fibres and can be independently tuned to the chosen
frequency, paving the way for arbitrarily large networks of optical
microcavities.


title:
Inconsistency of Pitman-Yor process mixtures for the number of
  components

abstract:
  In many applications, a finite mixture is a natural model, but it can be
difficult to choose an appropriate number of components. To circumvent this
choice, investigators are increasingly turning to Dirichlet process mixtures
(DPMs), and Pitman-Yor process mixtures (PYMs), more generally. While these
models may be well-suited for Bayesian density estimation, many investigators
are using them for inferences about the number of components, by considering
the posterior on the number of components represented in the observed data. We
show that this posterior is not consistent --- that is, on data from a finite
mixture, it does not concentrate at the true number of components. This result
applies to a large class of nonparametric mixtures, including DPMs and PYMs,
over a wide variety of families of component distributions, including
essentially all discrete families, as well as continuous exponential families
satisfying mild regularity conditions (such as multivariate Gaussians).


title:
Intrinsic Charm Parton Distribution Functions from CTEQ-TEA Global
  Analysis

abstract:
  We study the possibility of intrinsic (non-perturbative) charm in parton
distribution functions (PDF) of the proton, within the context of the CT10
next-to-next-to-leading order (NNLO) global analysis. Three models for the
intrinsic charm (IC) quark content are compared: (i) $\hat{c}(x) = 0$ (zero-IC
model); (ii) $\hat{c}(x)$ is parametrized by a valence-like parton distribution
(BHPS model); (iii) $\hat{c}(x)$ is parametrized by a sea-like parton
distribution (SEA model). In these models, the intrinsic charm content,
$\hat{c}(x)$, is included in the charm PDF at the matching scale $Q_c=m_c=1.3$
GeV. The best fits to data are constructed and compared. Correlations between
the value of $m_c$ and the amount of IC are also considered.


title:
Prospects for a Heavy Vector-Like Charge 2/3 Quark T search at the LHC
  with \sqrt{s}=14 TeV and 33 TeV. "A Snowmass 2013 Whitepaper"

abstract:
  We present the prospects for the discovery or exclusion of heavy vector-like
charge 2/3 quarks, T, in proton-proton collisions at two center-of-mass
energies, 14 and 33 TeV at the LHC. In this note, the pair production of T
quark and its antiparticle, with decays to W boson and a b quark (Wb), a top
quark and the Higgs boson (tH), and a top quark and Z boson (tZ) are
investigated. Higgs boson decays to $b\bar b$ and $W^+W^-$ final states are
selected for this study.


title:
Real-space structure of the impurity screening cloud in the Resonant
  Level Model

abstract:
  We present a detailed investigation of the impurity screening cloud in the
Resonant Level Model. The screening is visible in the structure of
impurity-bath correlators as a function of distance from the impurity. We
characterize the screening cloud through scaling analyses of impurity-bath
correlators and entanglement entropies. We devise and study several situations
where the screening cloud is destroyed or modified: finite temperatures,
energetic detuning of the impurity from the chemical potential, and the
situation of an unconventional bath with diverging density of states.


title: Lorentzian compact manifolds: isometries and geodesics

abstract:
  In this work we investigate families of compact Lorentzian manifolds in
dimension four. We show that every lightlike geodesic on such spaces is
periodic, while there are closed and non-closed spacelike and timelike
geodesics. Their isometry groups are computed. We also show that there is a non
trivial action by isometries of $\Heis_3(\RR)$ on the nilmanifold $S^1\times
(\Gamma_k \bsh \Heis_3(\RR))$ for $\Gamma_k$ a lattice of $\Heis_3(\RR)$.


title: A Canonical Partition of the Primes of Logic Functions

abstract:
  This paper presents algorithms that relate to the problem of finding a
minimum-cost sum-of-primes representation of a Boolean function f when the cost
function C is positive and additive. A set of primes whose sum equals f is
called a basis for f, so a solution to the problem is a minimum-cost basis.
  The algorithms construct the following canonical partition of the complete
set of primes and identify the members of sets 1, 2, and 3:
  (1) Essential Primes, which must be part of any basis for f,
  (2) Unnecessary Primes that cannot be part of a minimum-cost basis for f for
any positive additive cost function,
  (3) Unique disjoint sets of primes, PS1,...,PSN with associated "covering"
tables TS1,..., TSN such that any minimum-cost basis consists of the union of
the sets
  Essential Primes, QS1(C), ..., QSN(C) where QSi(C) is contained in PSi and
QSi(C) is a minimum-cost "cover" for PSi. Covering is defined by operation
Cascade(QS, TS), which has the property that QS covers PS if and only if
Cascade(QS, TS) is empty.
  The key to the results is the study of objects called Ancestor Sets. The
Ancestor Theorem proves that if A is an Ancestor Set for f, every minimum-cost
basis includes a minimum-cost cover for the set of primes PS in Ancestor Set A
and a minimum-cost cover for the set of primes that are not in A (and are not
covered by the the union of the Essentials with PS). The PSi in the partition
are the sets of primes in canonical disjoint Independent Ancestor Sets Ai,
which are easy to generate when the calculation of the primes (and their
consensus combinations) is within computational scope. The paper also presents
a condition under which QSi(C) can be easily determined, and another condition
such that PSi can be broken into disjoint pieces that can be minimized
separately.


title: Varieties Characterized by their Endomorphisms

abstract:
  We show that two varieties X and Y with isomorphic endomorphism semigroups
are isomorphic up to field automorphism if one of them is affine and contains a
copy of the affine line. A holomorphic version of this result is due to the
first author.


title:
Post-Newtonian parameters gamma and beta of scalar-tensor gravity with a
  general potential

abstract:
  We calculate the PPN parameters gamma and beta for scalar-tensor gravity with
a generic coupling function omega and scalar potential V in the Jordan
conformal frame in the case of a static spherically symmetric source. Since the
potential generally introduces a radial dependence to the effective
gravitational constant as well as to gamma and beta, we discuss the issue of
defining these PPN parameters and compare our expressions with previous
calculations in simpler cases. We confront our results with current
observational constraints on the values of gamma and beta and thus draw
restrictions on the form of the functions omega and V around their asymptotic
background values.


title:
Superconducting instability of a non-magnetic metallic band in an
  antiferromagnetic background

abstract:
  It is shown that a non-magnetic metallic band in the presence of an
antiferromagnetic background coupled only by the exchange interaction develops
a superconducting instability similar to the one described by BCS theory plus
additional terms that strongly renormalize the spin excitation spectra. A
Bardeen-Pines-like hole-hole interaction Hamiltonian, mediated by magnetic
excitations, is deduced from a microscopic model of a fermion band and a spin
band that interact with each other only via the exchange interaction. The
theory shows the appearance of an attractive interaction when the Fermi
velocity in the non-magnetic band is larger than the magnon velocity in the
magnetic band. The electron-magnon scattering is suppressed by the appearance
of a spin gap simultaneously with the superconducting state. Although this
model may well describe a general class of materials to be discovered, the
possibility that this theory could describe superconducting cuprates is
discussed.


title:
Magnetic Inhibition of Convection and the Fundamental Properties of
  Low-Mass Stars. I. Stars with a Radiative Core

abstract:
  Magnetic fields are hypothesized to inflate the radii of low-mass
stars---defined as less massive than 0.8$M_\odot$---in detached eclipsing
binaries (DEBs). We investigate this hypothesis using the recently introduced
magnetic Dartmouth stellar evolution code. In particular, we focus on stars
thought to have a radiative core and convective outer envelope by studying in
detail three individual DEBs: UV Psc, YY Gem, and CU Cnc. The results suggest
that the stabilization of thermal convection by a magnetic field is a plausible
explanation for the observed model-radius discrepancies. However, surface
magnetic field strengths required by the models are significantly stronger than
those estimated from the observed coronal X-ray emission. Agreement between
model predicted surface magnetic field strengths and those inferred from X-ray
observations can be found by assuming that the magnetic field sources its
energy from convection. This approach makes the transport of heat by convection
less efficient and is akin to reduced convective mixing length methods used in
other studies. Predictions for the metallicity and magnetic field strengths of
the aforementioned systems are reported. We also develop an expression relating
a reduction in the convective mixing length to a magnetic field strength in
units of the equipartition value. Our results are compared with those from
previous investigations to incorporate magnetic fields to explain the low-mass
DEB radius inflation. Finally, we explore how the effects of magnetic fields
might affect mass determinations using asteroseismic data and the implication
of magnetic fields on exoplanet studies.


title: Why is the superconducting Tc so high in rare-earth-doped CaFe2As2?

abstract:
  In rare-earth doped single crystalline CaFe2As2, the mysterious small volume
fraction which superconducts up to 49 K, much higher than the bulk Tc ~ 30s K,
has prompted a long search for a hidden variable that could enhance the Tc by
more than 30% in iron-based superconductors of the same structure. Here we
report a chemical, structural, and magnetic study of CaFe2As2 systematically
doped with La, Ce, Pr, and Nd. Coincident with the high Tc phase, we find
extreme magnetic anisotropy, accompanied by an unexpected doping-independent Tc
and equally unexpected superparamagnetic clusters associated with As vacancies.
These observations lead us to conjecture that the tantalizing Tc enhancement
may be associated with naturally occurring chemical interfaces and may thus
provide a new paradigm in the search for superconductors with higher Tc.


title:
Nonequilibrium first-order transition in coupled oscillator systems with
  inertia and noise

abstract:
  We study the dynamics of a system of coupled oscillators of distributed
natural frequencies, by including the features of both thermal noise,
parametrized by a temperature, and inertial terms, parametrized by a moment of
inertia. For a general unimodal frequency distribution, we report here the
complete phase diagram of the model in the space of dimensionless moment of
inertia, temperature, and width of the frequency distribution. We demonstrate
that the system undergoes a nonequilibrium first-order phase transition from a
synchronized phase at low parameter values to an incoherent phase at high
values. We provide strong numerical evidence for the existence of both the
synchronized and the incoherent phase, treating the latter analytically to
obtain the corresponding linear stability threshold that bounds the first-order
transition point from below. In the limit of zero noise and inertia, when the
dynamics reduces to the one of the Kuramoto model, we recover the associated
known continuous transition. At finite noise and inertia but in the absence of
natural frequencies, the dynamics becomes that of a well-studied model of
long-range interactions, the Hamiltonian mean-field model. Close to the
first-order phase transition, we show that the escape time out of metastable
states scales exponentially with the number of oscillators, which we explain to
be stemming from the long-range nature of the interaction between the
oscillators.


title: Non-universal SUGRA at LHC: Prospects and Discovery Potential

abstract:
  We explore supersymmetry (SUSY) parameter space with non-universal high scale
parameters in gravity mediated SUSY breaking (SUGRA) scenario that accommodates
a Higgs mass of (125$\pm$2) GeV while satisfying cold dark matter relic density
and other low energy constraints. We indicate a few benchmark points consistent
with different dark matter annihilation processes where third family squarks
are lighter than the first two as a requirement to keep the Higgs mass within
the limit. We show that bottom rich and leptonic final states have better reach
in such parameter space points and is the most likely scenario to discover SUSY
at the upcoming run of LHC with center-of-mass energy 14 TeV.


title:
Observational nuclear astrophysics: neutron-capture element abundances
  in old, metal-poor stars

abstract:
  The chemical abundances of metal-poor stars provide a great deal of
information regarding the individual nucleosynthetic processes that created the
observed elements and the overall process of chemical enrichment of the galaxy
since the formation of the first stars. Here we review the abundance patterns
of the neutron-capture elements (Z > 38) in those metal-poor stars and our
current understanding of the conditions and sites of their production at early
times. We also review the relative contributions of these different processes
to the build-up of these elements within the galaxy over time, and outline
outstanding questions and uncertainties that complicate the interpretation of
the abundance patterns observed in metal-poor stars. It is anticipated that
future observations of large samples of metal-poor stars will help discriminate
between different proposed neutron-capture element production sites and better
trace the chemical evolution of the galaxy.


title: The Ramsey Number $R(3,K_{10}-e)$ and Computational Bounds for $R(3,G)$

abstract:
  Using computer algorithms we establish that the Ramsey number $R(3,K_{10}-e)$
is equal to 37, which solves the smallest open case for Ramsey numbers of this
type. We also obtain new upper bounds for the cases of $R(3,K_k-e)$ for $11 \le
k \le 16$, and show by construction a new lower bound $55 \le R(3,K_{13}-e)$.
  The new upper bounds on $R(3,K_k-e)$ are obtained by using the values and
lower bounds on $e(3,K_l-e,n)$ for $l \le k$, where $e(3,K_k-e,n)$ is the
minimum number of edges in any triangle-free graph on $n$ vertices without
$K_k-e$ in the complement. We complete the computation of the exact values of
$e(3,K_k-e,n)$ for all $n$ with $k \leq 10$ and for $n \leq 34$ with $k = 11$,
and establish many new lower bounds on $e(3,K_k-e,n)$ for higher values of $k$.
  Using the maximum triangle-free graph generation method, we determine two
other previously unknown Ramsey numbers, namely $R(3,K_{10}-K_3-e)=31$ and
$R(3,K_{10}-P_3-e)=31$. For graphs $G$ on 10 vertices, %besides $G=K_{10}$,
this leaves 6 other open besides $G=K_{10}$, this leaves 6 open cases of the
form $R(3,G)$. The hardest among them appears to be $G=K_{10}-2K_2$, for which
we establish the bounds $31 \le R(3,K_{10}-2K_2) \le 33$.


title:
On completions of symmetric and antisymmetric block diagonal partial
  matrices

abstract:
  A partial matrix is a matrix where only some of the entries are given. We
determine the maximum rank of the symmetric completions of a symmetric partial
matrix where only the diagonal blocks are given and the minimum rank and the
maximum rank of the antisymmetric completions of an antisymmetric partial
matrix where only the diagonal blocks are given.


title: Enhanced Flow in Small-World Networks

abstract:
  The small-world property is known to have a profound effect on the navigation
efficiency of complex networks [J. M. Kleinberg, Nature 406, 845 (2000)].
Accordingly, the proper addition of shortcuts to a regular substrate can lead
to the formation of a highly efficient structure for information propagation.
Here we show that enhanced flow properties can also be observed in these
complex topologies. Precisely, our model is a network built from an underlying
regular lattice over which long-range connections are randomly added according
to the probability, $P_{ij}\sim r_{ij}^{-\alpha}$, where $r_{ij}$ is the
Manhattan distance between nodes $i$ and $j$, and the exponent $\alpha$ is a
controlling parameter. The mean two-point global conductance of the system is
computed by considering that each link has a local conductance given by
$g_{ij}\propto r_{ij}^{-\delta}$, where $\delta$ determines the extent of the
geographical limitations (costs) on the long-range connections. Our results
show that the best flow conditions are obtained for $\delta=0$ with $\alpha=0$,
while for $\delta \gg 1$ the overall conductance always increases with
$\alpha$. For $\delta\approx 1$, $\alpha=d$ becomes the optimal exponent, where
$d$ is the topological dimension of the substrate. Interestingly, this exponent
is identical to the one obtained for optimal navigation in small-world networks
using decentralized algorithms.


title:
Revision of the derivation of stellar rates from experiment and impact
  on Eu s-process contributions

abstract:
  A new, general formalism to include experimental data in revised stellar
rates is discussed, containing revised uncertainties. Application to the
s-process shows that the actual uncertainties in the neutron capture rates can
be larger than would be expected from the experimental errors alone. As a
specific example for how astrophysical conclusions can depend on the approach
selected to derive stellar rates, the 151Eu/(151Eu+153Eu) abundance ratio from
AGB star models is presented. Finally, a recommended workflow for the
derivation of stellar rates from experiment is laid out.


title: Quantum associative memory for the diagnosis of some tropical diseases

abstract:
  In this paper we present a model of Quantum Associative Memory which can be a
helpful tool for physicians without experience or laboratory facilities, for
the diagnosis of four tropical diseases (malaria, typhoid fever, yellow fever
and dengue) which have similar symptoms. The memory can distinguish single
infection from multi-infection. The algorithm used for Quantum Associative
Memory is an improve model of original algorithm made by Ventura for Quantum
Associative Memory. From the simulation results given, it appears that the
efficiency of recognition is good when a particular symptom of a disease with a
similar symptoms are inserted.


title:
Fundamental groups of finite volume, bounded negatively curved
  4-manifolds are not 3-manifold groups

abstract:
  We study noncompact, complete, finite volume, Riemannian 4-manifolds $M$ with
sectional curvature $-1<K<0$. We prove that $\pi_1 M$ cannot be a 3-manifold
group. A classical theorem of Gromov says that $M$ is homeomorphic to the
interior of a compact manifold $\M$ with boundary $\partial\barM$. We show that
for each $\pi_1$-injective boundary component $C$ of $\M$, the map $i_*$
induced by inclusion $i\colon C\rightarrow \M$ has infinite index image
$i_*(\pi_1 C)$ in $\pi_1 \M$. We also prove that $M$ cannot be homotoped to be
contained in $\partial\M$.


title: Nested Head-Tail Vlasov Solver

abstract:
  Nested Head-Tail (NHT) is a Mathematica-based Vlasov solver for transverse
oscillations in multi-bunch beams. It takes into account azimuthal, radial,
coupled-bunch and beam-beam degrees of freedom, single- and inter-bunch dipole
wakes, an arbitrary damper, beam-beam effects and Landau damping.


title:
Non-radial Oscillations in Rotating Giant Planets with Solid Cores:
  Application to Saturn and its Rings

abstract:
  Recent observations have revealed evidence for the global oscillations of
Jupiter and Saturn, which can potentially provide a new window into the
interior structure of giant planets. Motivated by these observations, we study
the non-radial oscillation modes of giant planets containing a solid core. Our
calculations include the elastic response of the core and consider a wide range
of possible values of the core shear modulus. While the elasticity of the core
only slightly changes the frequencies of acoustic modes, which reside mostly in
the fluid envelope, it adds two new classes of shear modes that are largely
confined to the core. We also calculate the effects of the Coriolis force on
the planetary oscillation modes. In addition to changing the mode frequencies,
the Coriolis force can cause the shear modes to mix with the f-modes. Such
mixing occurs when the frequencies of the shear mode and the f-mode are close
to each other, and results in "mixed modes" with similar properties that are
slightly split in frequency. We discuss our results in light of the recent work
by Hedman & Nicholson (2013), which revealed the presence of density waves in
Saturn's C-ring that appear to be excited by the gravitational perturbations
associated with the f-mode oscillations within Saturn. We find that the fine
splitting in wave frequencies observed in the rings can in principle be
explained by the rotation-induced mixing between core shear modes and f-modes,
possibly indicating the presence of a solid core within Saturn. However, in our
current calculations, which assume rigid-body rotation and include only
first-order rotational effects, significant fine-tuning in the planetary model
parameters is needed in order to achieve these mode mixings and to explain the
observed fine frequency splitting. We briefly discuss other effects that may
modify the f-modes and facilitate mode mixing.


title:
The Stochastic Solution to a Cauchy Problem for Degenerate Parabolic
  Equations

abstract:
  We study the stochastic solution to a Cauchy problem for a degenerate
parabolic equation arising from option pricing. When the diffusion coefficient
of the underlying price process is locally H\"older continuous with exponent
$\delta\in (0, 1]$, the stochastic solution, which represents the price of a
European option, is shown to be a classical solution to the Cauchy problem.
This improves the standard requirement $\delta\ge 1/2$. Uniqueness results,
including a Feynman-Kac formula and a comparison theorem, are established
without assuming the usual linear growth condition on the diffusion
coefficient. When the stochastic solution is not smooth, it is characterized as
the limit of an approximating smooth stochastic solutions. In deriving the main
results, we discover a new, probabilistic proof of Kotani's criterion for
martingality of a one-dimensional diffusion in natural scale.


title: The primordial helium abundance from updated emissivities

abstract:
  Observations of metal-poor extragalactic H II regions allow the determination
of the primordial helium abundance, Y_p. The He I emissivities are the
foundation of the model of the H II region's emission. Porter, Ferland, Storey,
& Detisch (2012) have recently published updated He I emissivities based on
improved photoionization cross-sections. We incorporate these new atomic data
and update our recent Markov Chain Monte Carlo analysis of the dataset
published by Izotov, Thuan, & Stasinska (2007). As before, cuts are made to
promote quality and reliability, and only solutions which fit the data within
95% confidence level are used to determine the primordial He abundance. The
previously qualifying dataset is almost entirely retained and with strong
concordance between the physical parameters. Overall, an upward bias from the
new emissivities leads to a decrease in Y_p. In addition, we find a general
trend to larger uncertainties in individual objects (due to changes in the
emissivities) and an increased variance (due to additional objects included).
From a regression to zero metallicity, we determine Y_p = 0.2465 +/- 0.0097, in
good agreement with the Planck result of Y_p = 0.2485 +/- 0.0002. In the
future, a better understanding of why a large fraction of spectra are not well
fit by the model will be crucial to achieving an increase in the precision of
the primordial helium abundance determination.


title: Dark Matter Annihilations in the Causal Diamond

abstract:
  We investigate the implications of dark matter annihilations for cosmological
parameter constraints using the causal entropic principle. In this approach
cosmologies are weighted by the total entropy production within a causally
connected region of spacetime. We calculate the expected entropy from dark
matter annihilations within the causal diamond and investigate the preferred
values of the cosmological constant and the mass and annihilation cross section
of the annihilating dark matter and their dependence on the assumptions in the
models. For realistic values of the cross section we typically find preferred
values of $\Lambda $ on the order of $10^{-5}$ of the present value assuming
dark matter annihilations are the primary source of entropy production. The
greatest amount of entropy production from dark matter within the causal
diamond is likely to occur with light keV scale dark matter with low
annihilation cross section. We also investigate the effect of combining this
entropy with the entropy production from stars, and show that if the primary
source of entropy production is from stars, varying the dark matter cross
section directly produces a preferred value of $\Omega_m$ in excellent
agreement with observations.


title: The Euclidean distance degree of an algebraic variety

abstract:
  The nearest point map of a real algebraic variety with respect to Euclidean
distance is an algebraic function. For instance, for varieties of low rank
matrices, the Eckart-Young Theorem states that this map is given by the
singular value decomposition. This article develops a theory of such nearest
point maps from the perspective of computational algebraic geometry. The
Euclidean distance degree of a variety is the number of critical points of the
squared distance to a generic point outside the variety. Focusing on varieties
seen in applications, we present numerous tools for exact computations.


title:
Donaldson-Thomas Invariants of 2-Dimensional sheaves inside threefolds
  and modular forms

abstract:
  Motivated by the S-duality conjecture, we study the Donaldson-Thomas
invariants of the 2 dimensional Gieseker stable sheaves on a threefold. These
sheaves are supported on the fibers of a nonsingular threefold X fibered over a
nonsingular curve. In the case where X is a K3 fibration, we express these
invariants in terms of the Euler characteristic of the Hilbert scheme of points
on the K3 fiber and the Noether-Lefschetz numbers of the fibration. We prove
that a certain generating function of these invariants is a vector modular form
of weight -3/2 as predicted in S-duality.


title: Counting curves on surfaces in Calabi-Yau 3-folds

abstract:
  Motivated by S-duality modularity conjectures in string theory, we define new
invariants counting a restricted class of 2-dimensional torsion sheaves,
enumerating pairs $Z\subset H$ in a Calabi-Yau threefold X. Here H is a member
of a sufficiently positive linear system and Z is a 1-dimensional subscheme of
it. The associated sheaf is the ideal sheaf of $Z\subset H$, pushed forward to
X and considered as a certain Joyce-Song pair in the derived category of X. We
express these invariants in terms of the MNOP invariants of X.


title: Accelerating a Cloud-Based Software GNSS Receiver

abstract:
  In this paper we discuss ways to reduce the execution time of a software
Global Navigation Satellite System (GNSS) receiver that is meant for offline
operation in a cloud environment. Client devices record satellite signals they
receive, and send them to the cloud, to be processed by this software. The goal
of this project is for each client request to be processed as fast as possible,
but also to increase total system throughput by making sure as many requests as
possible are processed within a unit of time. The characteristics of our
application provided both opportunities and challenges for increasing
performance. We describe the speedups we obtained by enabling the software to
exploit multi-core CPUs and GPGPUs. We mention which techniques worked for us
and which did not. To increase throughput, we describe how we control the
resources allocated to each invocation of the software to process a client
request, such that multiple copies of the application can run at the same time.
We use the notion of effective running time to measure the system's throughput
when running multiple instances at the same time, and show how we can determine
when the system's computing resources have been saturated.


title: Commuting matrices, and modules over Artinian local rings

abstract:
  Gerstenhaber showed in 1961 that any commuting pair of n x n matrices over a
field k generates a k-algebra A of k-dimension \leq n. A well-known example
shows that the corresponding statement for 4 matrices is false. The question
for 3 matrices is open.
  Gerstenhaber's result can be looked at as a statement about the relation
between the length of a 2-generator finite-dimensional commutative k-algebra A
and the lengths of faithful A-modules. Wadsworth generalized this result to a
larger class of commutative rings than those generated by two elements over a
field. We recover his generalization, using a slightly improved argument.
  We then explore some examples, raise further questions, and make a bit of
progress toward answering some of them.
  An appendix gives some results on generation and subdirect decompositions of
modules over not necessarily commutative Artinian rings, generalizing a special
case used in the paper.
  What I originally thought of as my main result turned out to have been
anticipated by Wadsworth, so I probably won't submit this for publication
unless I find further strong results to add. However, others may find
interesting the observations, partial results, and questions noted, and perhaps
make some progress on them.


title: An introduction to the half-infinite wedge

abstract:
  After a quick review of the representation theory of the symmetric group, we
give an exposition of the tools brought about by the so-called half-infinite
wedge representation of the infinite symmetric group. We show how these can be
applied to find the limit shapes of several distributions on partitions. We
also briefly review the variational methods available to compute these limit
shapes.


title:
Fourier transforms of positive definite kernels and the Riemann
  $\xi$-Function

abstract:
  The purpose of this paper is to investigate the distribution of zeros of
entire functions which can be represented as the Fourier transforms of certain
admissible kernels. The principal results bring to light the intimate
connection between the Bochner-Khinchin-Mathias theory of positive definite
kernels and the generalized real Laguerre inequalities. The concavity and
convexity properties of the Jacobi theta function play a prominent role
throughout this work. The paper concludes with several questions and open
problems.


title:
Generalized Donaldson-Thomas Invariants of 2-Dimensional sheaves on
  local P^2

abstract:
  Let X be the total space of the canonical bundle of P^2. We study the
generalized Donaldson-Thomas invariants, defined in the work of Joyce-Song, of
the moduli spaces of the 2-dimensional Gieseker semistable sheaves on X with
first Chern class equal to k times the class of the zero section of X. When
k=1, 2 or 3, and semistability implies stability, we express the invariants in
terms of known modular forms. We prove a combinatorial formula for the
invariants when k=2 in the presence of the strictly semistable sheaves, and
verify the BPS integrality conjecture of Joyce-Song in some cases.


title: Neutron capture rates and r-process nucleosynthesis

abstract:
  Simulations of r-process nucleosynthesis require nuclear physics information
for thousands of neutron-rich nuclear species from the line of stability to the
neutron drip line. While arguably the most important pieces of nuclear data for
the r-process are the masses and beta decay rates, individual neutron capture
rates can also be of key importance in setting the final r-process abundance
pattern. Here we consider the influence of neutron capture rates in forming the
A~80 and rare earth peaks.


title:
The sensitivity of r-process nucleosynthesis to the properties of
  neutron-rich nuclei

abstract:
  About half of the heavy elements in the Solar System were created by rapid
neutron capture, or r-process, nucleosynthesis. In the r-process, heavy
elements are built up via a sequence of neutron captures and beta decays in
which an intense neutron flux pushes material out towards the neutron drip
line. The nuclear network simulations used to test potential astrophysical
scenarios for the r-process therefore require nuclear physics data (masses,
beta decay lifetimes, neutron capture rates, fission probabilities) for
thousands of nuclei far from stability. Only a small fraction of this data has
been experimentally measured. Here we discuss recent sensitivity studies that
aim to determine the nuclei whose properties are most crucial for r-process
calculations.


title:
Sensitivity studies for r-process nucleosynthesis in three astrophysical
  scenarios

abstract:
  In rapid neutron capture, or r-process, nucleosynthesis, heavy elements are
built up via a sequence of neutron captures and beta decays that involves
thousands of nuclei far from stability. Though we understand the basics of how
the r-process proceeds, its astrophysical site is still not conclusively known.
The nuclear network simulations we use to test potential astrophysical
scenarios require nuclear physics data (masses, beta decay lifetimes, neutron
capture rates, fission probabilities) for all of the nuclei on the neutron-rich
side of the nuclear chart, from the valley of stability to the neutron drip
line. Here we discuss recent sensitivity studies that aim to determine which
individual pieces of nuclear data are the most crucial for r-process
calculations. We consider three types of astrophysical scenarios: a traditional
hot r-process, a cold r-process in which the temperature and density drop
rapidly, and a neutron star merger trajectory.


title:
Comparative studies of many-body corrections to an interacting Bose
  condensate

abstract:
  We compare many-body theories describing fluctuation corrections to the
mean-field theory in a weakly interacting Bose-condensed gas. Using a
generalized random-phase approximation, we include both density fluctuations
and fluctuations in the particle-particle scattering channel in a consistent
manner. We also separately examine effects of the fluctuations within the
framework of the random-phase approximation. Effects of fluctuations in the
particle-particle scattering channel are also separately examined by using the
many-body T-matrix approximation. We assess these approximations with respect
to the transition temperature, the order of phase transition, as well as the
so-called Nepomnyashchii-Nepomnyashchii identity, which states the vanishing
off-diagonal self-energy in the low-energy and low-momentum limit. Since the
construction of a consistent theory for interacting bosons which satisfies
various required conditions is a long standing problem in cold atom physics,
our results would be useful for this important challenge.


title: Inelastic Current Noise in Nanoscale Systems: Scattering Theory Analysis

abstract:
  We present a scattering theory description for the inelastic current noise in
the presence of electron-vibration interactions. In this description, we
specify elastic and inelastic scattering contributions to the shot noise by
examining charge transfers between scattering states and energy exchange
between electrons and vibrations. The elastic and inelastic scattering
processes are further decomposed into current correlations of electrons at the
same energy and those of electrons at different energies. Focusing on the
inelastic noise signals defined as steps in the voltage derivative of the shot
noise, we show that single-channel systems have two ranges of transmission at
which the inelastic noise signals exhibit the crossover between positive and
negative signs. In a high transmission regime, even and odd vibrational modes
of mirror-symmetric systems provide upper and lower bounds to the ratio of the
inelastic noise signal to the conductance step. This can be a theoretical
justification for models used to understand the recent noise experiment [Phys.
Rev. Lett. 108, 146602 (2012)] and numerical calculations on gold atomic chains
[Phys. Rev. B 86, 155411 (2012)].


title: Even-dimensional General Relativity from Born-Infeld gravity

abstract:
  It is an accepted fact that requiring the Lovelock theory to have the maximun
possible number of degree of freedom, fixes the parameters in terms of the
gravitational and the cosmological constants. In odd dimensions, the Lagrangian
is a Chern-Simons form for the (A)dS group. In even dimensions, the action has
a Born-Infeld-like form. Recently was shown that standard odd-dimensional
General Relativity can be obtained from Chern-Simons Gravity theory for a
certain Lie algebra B. Here we report on a simple model that suggests a
mechanism by which standard even-dimensional General Relativity may emerge as a
weak coupling constant limit of a Born-Infeld theory for a certain Lie
subalgebra of the algebra B. Possible extension to the case of even-dimensional
supergravity is briefly discussed.


title:
Logistic Growth for the Nuzi Cuneiform Tablets: Analyzing Family
  Networks in Ancient Mesopotamia

abstract:
  We reconstruct the year of publication of each cuneiform tablet of the Nuzi
society in ancient Mesopotamia. The tablets, are on land transaction, marriage,
loan, slavery contracts etc. The number of tablets seem to increase by logistic
growth until saturation. It may show the dynamics of concentration of lands or
other properties into few powerful families in a period of about twenty years.
We reconstruct family trees and social networks of Nuzi and estimate the
publication years of cuneiform tablets consistently with the trees and
networks, formulating least squares problems with linear inequality
constraints.


title:
An electrical conductivity relaxation study of oxygen transport in
  samarium doped ceria

abstract:
  The efficacy of the electrical conductivity relaxation (ECR) technique for
investigating the oxygen transport properties of mixed conducting oxides has
been evaluated. Fifteen mol% samarium doped ceria (SDC15), for which
approximate values of the two principal transport properties, bulk oxygen
diffusivity, $D_{Chem}$, and surface reaction rate constant, $k_S$, can be
found in the literature, was chosen as the benchmark material against which to
validate the methodology. Measurements were carried out at temperatures between
750 $^\circ$C and 850 $^\circ$C and over a wide range of oxygen partial
pressures. An unexpectedly high p-type electronic transference number enabled
ECR measurements under oxidizing conditions. A systematic data analysis
procedure was developed to permit reliable extraction of the kinetic parameters
even in the general case of simultaneous bulk and surface limitation. The
$D_{Chem}$ from this study showed excellent qualitative and quantitative
agreement with expected values, falling in the range from $\sim 2\times10^{-5}$
to $2\times10^{-4}$ cm$^2$/s. The surface reaction constant under H$_2$/H$_2$O
mixtures also showed good agreement with literature results. Remarkably, this
value increased by a factor of 40 under mixtures of CO/CO$_2$ or O$_2$/Ar. This
observation suggests kinetic advantages for production of CO rather than H$_2$
in a two-step solar-driven thermochemical process based on samarium doped
ceria.


title:
Automated Verification of Interactive Rule-Based Configuration Systems
  (Additional Material)

abstract:
  Additional material for the original paper "Automated Verification of
Interactive Rule-Based Configuration Systems".


title: Congestion Due to Random Walk Routing

abstract:
  In this paper we derive an analytical expression for the mean load at each
node of an arbitrary undirected graph for the uniform multicommodity flow
problem under random walk routing. We show the mean load is linearly dependent
on the nodal degree with a common multiplier equal to the sum of the inverses
of the non-zero eigenvalue of the graph Laplacian. Even though some aspects of
the mean load value, such as linear dependence on the nodal degree, are
intuitive and may be derived from the equilibrium distribution of the random
walk on the undirected graph, the exact expression for the mean load in terms
of the full spectrum of the graph has not been known before. Using the explicit
expression for the mean load, we give asymptotic estimates for the load on a
variety of graphs whose spectral density are well known. We conclude with
numerical computation of the mean load for other well-known graphs without
known spectral densities.


title:
Hawking radiation of Reissner-Nordstrom-de Sitter black hole by
  Hamilton-Jacobi method

abstract:
  In Refs. (M. Atiqur Rahman, M. Ilias Hossain (2012) Phys. Lett. B {\bf 712}
1), we have developed Hamilton-Jacobi method for dynamical spacetime and
discussed Hawking radiation of Schwarzschild-de Sitter black hole by massive
particle tunneling method. In this letter, we have investigated the hawking
purely thermal and nonthermal radiations of Reissner-Nordstr\"{o}m-de Sitter
(RNdS) black hole. We have considered energy and angular momentum as conserved
and shown that the tunneling rate is related to the change of
Bekenstein-Hawking entropy and the derived emission spectrum deviates from the
pure thermal spectrum. The results we have obtained for RNdS black hole is also
in accordance with Parikh and Wilczek\rq s opinion and recovered the new result
for Hawking radiation of RNdS black hole.


title: C-Semi- Inner Product Spaces

abstract:
  In this paper we introduce a generalization of Hilbert C-modules which are
pre- Finsler module namely C-semi-inner product spaces. Some properties and
results of such spaces are investigated, specially the orthogonality in these
spaces will be considered. We then study bounded linear operators on
C-semi-inner product spaces.


title:
Ballistic quantum state transfer in spin chains: general theory for
  quasi-free models and arbitrary initial states

abstract:
  Ballistic quantum-information transfer through spin chains is based on the
idea of making the spin dynamics ruled by collective excitations with linear
dispersion relation. Unlike perfect state transfer schemes, a ballistic
transmission requires only a minimal engineering of the interactions; in fact,
for most practical purposes, the optimization of the couplings to the ends of
the chain is sufficient to obtain an almost perfect transmission. In this work
we review different ballistic quantum-state transfer protocols based on the
dynamics of quasi-free spin chains, and further generalize them both at zero
and finite temperature. In particular, besides presenting novel analytical
results for XX, XY, and Ising spin models, it is shown how, via a complete
control on the first and last two qubits of the chain, destructive thermal
effects can be cancelled, leading to a high-quality state transmission
irrespective of the temperature.


title:
First-principles Study On The Electronic And Optical Properties Of Cubic
  ABX3 Halide Perovskites

abstract:
  The electronic properties of ABX3 (A = Cs, CH3NH3, NH2CHNH2; B = Sn, Pb; X =
Cl, Br, I) type compounds in the cubic phase are systematically studied using
the first-principles calculations. We find that these compounds have direct
band gaps at R point where the valance band maximum is an anti-bonding state of
B s-X p coupling, while the conduction band minimum is a non-bonding state with
B p characters. The chemical trend of their properties as A or B or X varies is
fully investigated, which is of great importance to understand and optimize
this kind of solar cell materials. We find that: (i) as the size of A
increases, the band gap of ABX3 will increase; (ii) as B varies from Sn to Pb,
the band gap of ABX3 will increase; and (iii) as X ranges from Cl to Br to I,
the band gap will decrease. We explained these trends by analyzing their band
structures. Furthermore, optical properties of the ABX3 compounds are
investigated. Our calculations show that taking into account the spin-orbit
coupling effect is crucial for predicting the accurate band gap of these halide
perovskites. We predict that CH3NH3SnBr3 is a promising material for solar
cells absorber with a perfect band gap and good optical absorption.


title:
Origin of defects responsible for charge transport in resistive random
  access memory based on hafnia

abstract:
  A promising candidate for universal memory, which would involve combining the
most favourable properties of both high-speed dynamic random access memory
(DRAM) and non-volatile flash memory, is resistive random access memory
(ReRAM). ReRAM is based on switching back and forth from a high-resistance
state (HRS) to a low-resistance state (LRS). ReRAM cells are small, allowing
for the creation of memory on the scale of terabits. One of the most promising
materials for use as the active medium in resistive memory is hafnia (HfO$_2$).
  However, an unresolved physics is the nature of defects and traps that are
responsible for the charge transport in HRS state of resistive memory.
  In this study, we demonstrated experimentally and theoretically that oxygen
vacancies are responsible for the HRS charge transport in resistive memory
elements based on HfO$_2$. We also demonstrated that LRS transport occurs
through a mechanism described according to percolation theory.
  Based on the model of multiphonon tunneling between traps, and assuming that
the electron traps are oxygen vacancies, good quantitative agreement between
the experimental and theoretical data of current-voltage characteristics were
achieved. The thermal excitation energy of the traps in hafnia was determined
based on the excitation spectrum and luminescence of the oxygen vacancies.
  The findings of this study demonstrate that in resistive memory elements
using hafnia, the oxygen vacancies in hafnia play a key role in creating
defects in HRS charge transport.


title:
Liquid Crystal Equations with Infinite Energy Local Well-posedness and
  Blow Up Criterion

abstract:
  In this paper, we consider the Cauchy problem of the incompressible liquid
crystal equations in $n$ dimensions. We prove the local well-posedness of mild
solutions to the liquid crystal equations with $L^\infty$ initial data, in
particular, the initial energy may be infinite. We prove that the solutions are
smooth with respect to the space variables away from the initial time. Based on
this regularity estimate, we employ the blow up argument and Liouville type
theorems to establish vorticity direction type blow up criterions for the type
I mild solutions established in the present paper.


title:
SilentSense: Silent User Identification via Dynamics of Touch and
  Movement Behavioral Biometrics

abstract:
  With the increased popularity of smartphones, various security threats and
privacy leakages targeting them are discovered and investigated. In this work,
we present \ourprotocoltight, a framework to authenticate users silently and
transparently by exploiting dynamics mined from the user touch behavior
biometrics and the micro-movement of the device caused by user's screen-touch
actions. We build a "touch-based biometrics" model of the owner by extracting
some principle features, and then verify whether the current user is the owner
or guest/attacker. When using the smartphone, the unique operating dynamics of
the user is detected and learnt by collecting the sensor data and touch events
silently. When users are mobile, the micro-movement of mobile devices caused by
touch is suppressed by that due to the large scale user-movement which will
render the touch-based biometrics ineffective. To address this, we integrate a
movement-based biometrics for each user with previous touch-based biometrics.
We conduct extensive evaluations of our approaches on the Android smartphone,
we show that the user identification accuracy is over 99%.


title: Locally Finite Root Supersystems

abstract:
  We introduce the notion of locally finite root supersystems as a
generalization of both locally finite root systems and generalized root
systems. We classify irreducible locally finite root supersystems.


title: Note on affine Deligne-Lusztig varieties

abstract:
  This note is based on my talk at ICCM 2013, Taipei. We give an exposition of
the group-theoretic method and recent results on the questions of non-emptiness
and dimension of affine Deligne-Lusztig varieties in affine flag varieties.


title:
Zeros of the partition function and dynamical singularities in
  spin-glass systems

abstract:
  We study spin-glass systems characterized by continuous occurrence of
singularities. The theory of Lee-Yang zeros is used to find the singularities.
By using the replica method in mean-field systems, we show that two-dimensional
distributions of zeros of the partition function in a complex parameter plane
are characteristic feature of random systems. The results of several models
indicate that the concept of chaos in the spin-glass state is different from
that of the replica symmetry breaking. We discuss that a chaotic phase at
imaginary temperature is different from the spin-glass phase and is accessible
by quantum dynamics in a quenching protocol.


title:
Self-seeded lasing in ionized air pumped by 800 nm femtosecond laser
  pulses

abstract:
  We report on the lasing in air and pure nitrogen gas pumped by a single 800
nm femtosecond laser pulse. Depending on gas pressure, incident laser power and
beam convergence, different lasing lines are observed in the forward direction
with rapid change of their relative intensities. The lines are attributed to
transitions between vibrational and rotational levels of the first negative
band of the singly charged nitrogen molecule-ion. We show that self-seeding
plays an important role in the observed intensity changes.


title:
Electron carrier-mediated room temperature ferromagnetism in anatase
  (Ti,Co)O2

abstract:
  Since the discovery of room temperature ferromagnetism in (Ti,Co)O2, the
mechanism has been under discussion for a decade. Particularly, the central
concern has been whether or not the ferromagnetic exchange interaction is
mediated by charge carriers like (Ga,Mn)As. Recent two studies on the control
of ferromagnetism in anatase (Ti,Co)O2 at room temperature via electric field
effect [Y. Yamada et al., Science 332, 1065 (2011)] and chemical doping [Y.
Yamada et al., Appl. Phys. Lett. 99, 242502 (2011)] indicate a principal role
of electrons in the carrier-mediated exchange interaction. In this article, the
authors review fundamental properties of anatase (Ti,Co)O2 and discuss the
carrier mediated ferromagnetism.


title: Primacy analysis of the system of Bulgarian cities

abstract:
  We study the primacy in the Bulgarian urban system. Two groups of cities are
studied: (i) the whole Bulgaria city system that contains about 250 cities and
is studied in the time interval between 2004 and 2011; and (ii) A system of 33
cities, studied over the time interval 1887 till 2010. For these cities the
1946 population was over $10\ 000$ inhabitants. The notion of primacy in the
two systems of cities is studied first from the global primacy index of
Sheppard [$^1$]. Several (new) additional indices are introduced in order to
compensate defects in the Sheppard index. Numerical illustrations are
illuminating through the so called "length ratio".


title:
Effect of loss on the dispersion relation of photonic and phononic
  crystals

abstract:
  A theoretical analysis is made of the transformation of the dispersion
relation of waves in artificial crystals under the influence of loss, including
the case of photonic and phononic crystals. Considering a general dispersion
relation in implicit form, an analytic procedure is derived to obtain the
transformed dispersion relation. It is shown that the dispersion relation is
generally shifted in the complex $(k,\omega)$ plane, with $k$ the wavenumber
and $\omega$ the angular frequency. The value of the shift is obtained
explicitly as a function of the perturbation of material constants accounting
for loss. The method is shown to predict correctly the transformation of the
complex band structure $k(\omega)$. Several models of the dispersion relation
near a symmetry point of the Brillouin zone are analyzed. A lower bound for the
group velocity, related to the local shape of the band around symmetry points,
is derived for each case.


title: A Combination of Flow Shop Scheduling and the Shortest Path Problem

abstract:
  This paper studies a combinatorial optimization problem which is obtained by
combining the flow shop scheduling problem and the shortest path problem. The
objective of the obtained problem is to select a subset of jobs that
constitutes a feasible solution to the shortest path problem, and to execute
the selected jobs on the flow shop machines to minimize the makespan. We argue
that this problem is NP-hard even if the number of machines is two, and is
NP-hard in the strong sense for the general case. We propose an intuitive
approximation algorithm for the case where the number of machines is an input,
and an improved approximation algorithm for fixed number of machines.


title:
Combinations of Some Shop Scheduling Problems and the Shortest Path
  Problem: Complexity and Approximation Algorithms

abstract:
  We consider several combinatorial optimization problems which combine the
classic shop scheduling problems, namely open shop scheduling or job shop
scheduling, and the shortest path problem. The objective of the obtained
problem is to select a subset of jobs that forms a feasible solution of the
shortest path problem, and to execute the selected jobs on the open (or job)
shop machines to minimize the makespan. We show that these problems are NP-hard
even if the number of machines is two, and cannot be approximated within a
factor less than 2 if the number of machines is an input unless P=NP. We
present several approximation algorithms for these combination problems.


title: Chiral-odd pion generalized parton distributions beyond leading twist

abstract:
  We define in a systematic way, based on the light-cone collinear
factorization method, the chiral-odd generalized parton distributions (GPDs) of
a pseudoscalar hadron (such as the pi0) up to twist 5. For that, we introduce
the relevant matrix elements for 2-parton non-local operators, as well as
matrix elements for 3-parton non-local correlators. Their detailed
parametrization is fixed based on parity, charge conjugation and time reversal
invariance. This leads to the introduction of 20 real GPDs, whose symmetry
properties are explicitely given. The reduction of these GPDs to a minimal set
is performed by the use of constraints provided by QCD equations of motion and
rotation on the light-cone. We show that these 20 GPDs can be expressed through
8 GPDs which satisfy 4 integral sum rules. A surprising outcome of this
analysis is the fact that, when assuming the vanishing of 3-parton correlators,
as in the so-called Wandzura-Wilczek approximation, the whole set of GPDs
vanishes.


title: Higher spin fields with reversed spin-statistics relation

abstract:
  A construction of massive free fields with arbitrary spin and reversed
spin-statistics relation is presented. The main idea of the construction is to
consider fields that transform according to representations of the Lorentz
group that are doubled in comparison with the representations according to
which normal (physical) fields transform. This allows the definition of
opposite commutation properties for these fields, while the spin of the
particles they describe remains unchanged. The correspondence established by
the construction between fields obeying normal and reversed spin-statistics
relation makes it possible to express e.g. the polarization states,
(anti)commutators, or Feynman propagators of the latter fields in terms of
those of the normal fields to which they correspond. The cases of the scalar
and Dirac fields are discussed in additional detail.


title:
Artificial Intelligence Based Cognitive Routing for Cognitive Radio
  Networks

abstract:
  Cognitive radio networks (CRNs) are networks of nodes equipped with cognitive
radios that can optimize performance by adapting to network conditions. While
cognitive radio networks (CRN) are envisioned as intelligent networks,
relatively little research has focused on the network level functionality of
CRNs. Although various routing protocols, incorporating varying degrees of
adaptiveness, have been proposed for CRNs, it is imperative for the long term
success of CRNs that the design of cognitive routing protocols be pursued by
the research community. Cognitive routing protocols are envisioned as routing
protocols that fully and seamless incorporate AI-based techniques into their
design. In this paper, we provide a self-contained tutorial on various AI and
machine-learning techniques that have been, or can be, used for developing
cognitive routing protocols. We also survey the application of various classes
of AI techniques to CRNs in general, and to the problem of routing in
particular. We discuss various decision making techniques and learning
techniques from AI and document their current and potential applications to the
problem of routing in CRNs. We also highlight the various inference, reasoning,
modeling, and learning sub tasks that a cognitive routing protocol must solve.
Finally, open research issues and future directions of work are identified.


title:
Quantum Phase Diagram of the Triangular-Lattice XXZ Model in a Magnetic
  Field

abstract:
  The triangular lattice of S=1/2 spins with XXZ anisotropy is a ubiquitous
model for various frustrated systems in different contexts. We determine the
quantum phase diagram of the model in the plane of the anisotropy parameter and
the magnetic field by means of a large-size cluster mean-field method with a
scaling scheme. We find that quantum fluctuations break up the nontrivial
continuous degeneracy into two first-order phase transitions. In between the
two transition boundaries, the degeneracy lifting results in the emergence of a
new coplanar phase not predicted in the classical counterpart of the model. We
suggest that the quantum phase transition to the nonclassical coplanar state
can be observed in triangular-lattice antiferromagnets with large easy-plane
anisotropy or in the corresponding optical-lattice systems.


title: On the determinant of hexagonal grids $H_{k,n}$

abstract:
  We analyse the problem of singularity of graphs for hexagonal grid graphs. We
introduce methods for transforming weighted graph, which do not change the
determinant of adjacency matrix. We use these methods to calculate the
determinant of all hexagonal grid graphs which describe certain hexagon-shaped
benzenoid systems. The final result is the explicit formula for the determinant
of graphs $H_{k,n}$. From the theorem we draw the conclusion, that all graphs
of this kind are non-singular.


title:
Caching Gain in Wireless Networks with Fading: A Multi-User Diversity
  Perspective

abstract:
  We consider the effect of caching in wireless networks where fading is the
dominant channel effect. First, we propose a one-hop transmission strategy for
cache-enabled wireless networks, which is based on exploiting multi-user
diversity gain. Then, we derive a closed-form result for throughput scaling of
the proposed scheme in large networks, which reveals the inherent trade-off
between cache memory size and network throughput. Our results show that
substantial throughput improvements are achievable in networks with sources
equipped with large cache size. We also verify our analytical result through
simulations.


title:
Three and four-body systems in one dimension: integrability,
  superintegrability and discrete symmetries

abstract:
  Families of three-body Hamiltonian systems in one dimension have been
recently proved to be maximally superintegrable by interpreting them as
one-body systems in the three-dimensional Euclidean space, examples are the
Calogero, Wolfes and Tramblay Turbiner Winternitz systems. For some of these
systems, we show in a new way how the superintegrability is associated with
their dihedral symmetry in the three-dimensional space, the order of the
dihedral symmetries being associated with the degree of the polynomial in the
momenta first integrals. As a generalization, we introduce the analysis of
integrability and superintegrability of four-body systems in one dimension by
interpreting them as one-body systems with the symmetries of the Platonic
polyhedra in the four-dimensional Euclidean space. The paper is intended as a
short review of recent results in the sector, emphasizing the relevance of
discrete symmetries for the superintegrability of the systems considered.


title:
The disk evaporation model for the spectral features of low-luminosity
  active galactic nuclei

abstract:
  Observations show that the accretion flows in low-luminosity active galactic
nuclei (LLAGNs) probably have a two-component structure with an inner ADAF and
an outer truncated accretion disk. As shown by Taam et al. (2012), the
truncation radius as a function of mass accretion rate is strongly affected by
including the magnetic field within the framework of disk evaporation model,
i.e., an increase of the magnetic field results in a smaller truncation radius
of the accretion disk. In this work, we calculate the emergent spectrum of an
inner ADAF + an outer truncated accretion disk around a supermassive black hole
based on the prediction by Taam et al. (2012). It is found that an increase of
the magnetic field from $\beta=0.8$ to $\beta=0.5$ (with magnetic pressure
$p_{\rm m}=B^2/{8\pi}=(1-\beta)p_{\rm tot}$, $p_{\rm tot}=p_{\rm gas}+p_{\rm
m}$) results in an increase of $\sim 8.7$ times of the luminosity from the
truncated accretion disk. We found that the equipartition of gas pressure to
magnetic pressure, i.e., $\beta=0.5$, failed to explain the observed
anti-correlation between $L_{\rm 2-10 keV}/L_{\rm Edd}$ and the bolometric
correction $\kappa_{\rm 2-10 keV}$ (with $\kappa_{\rm 2-10 keV} = L_{\rm
bol}/L_{\rm 2-10 keV}$). The emergent spectra for larger value $\beta=0.8$ or
$\beta=0.95$ can well explain the observed $L_{\rm 2-10 keV}/L_{\rm
Edd}$-$\kappa_{\rm 2-10 keV}$ correlation. We argue that in the disk
evaporation model, the electrons in the corona are assumed to be heated only by
a transfer of energy from the ions to electrons via Coulomb collisions, which
is reasonable for the accretion with a lower mass accretion rate. Coulomb
heating is the dominated heating mechanism for the electrons only if the
magnetic field is strongly sub-equipartition, which is roughly consistent with
observations.


title:
The \gamma\ parameter in Brans-Dicke-like (light-)Scalar-Tensor theory
  with a universal scalar/matter coupling

abstract:
  The post-Newtonian parameter \gamma\ resulting from a universal scalar/matter
coupling is investigated in Brans-Dicke-like Scalar-Tensor theories where the
scalar potential is assumed to be negligible. Conversely to previous studies,
we use a perfect fluid formalism in order to get the explicit scalar-field
equation. It is shown that the metric can be put in its standard post-Newtonian
form. However, it is pointed out that 1-\gamma\ could be either positive, null
or negative for finite value of \omega_0, depending on the coupling function;
while Scalar-Tensor theories without coupling always predict \gamma<1 for
finite value of \omega_0.


title: Harmonic morphisms and eigenfamilies on the exceptional Lie group G2

abstract:
  We construct harmonic morphisms on the compact simple Lie group G2. The
construction uses eigenfamilies in a representation theoretic scheme.


title:
The NGC 3341 minor merger: a panchromatic view of the active galactic
  nucleus in a dwarf companion

abstract:
  We present X-ray (Chandra), radio (EVLA and EVN), and archival optical data
of the triple-merging system in NGC3341. Our panchromatic analysis confirms the
presence of a Seyfert 2 AGN in NGC3341B, one of the secondary dwarf companions.
On the other hand, the nucleus of the primary galaxy, consistent with a
star-forming region of a few solar masses per year, and NGC3341C are very
unlikely to host an AGN. We therefore suggest that NGC3341 is an exceptional
example of an AGN triggered in the satellite galaxy of a minor-merging system.
The existence of such a system can have important implications in the models of
hierarchical growth of structures. Further observational and theoretical
efforts on NGC3341 and potentially similar sources are needed in order to
understand the role of minor mergers on the onset of AGN activity, and in the
evolution of massive galaxies.


title:
Meson dominance implications for the bottomness preserving decays of the
  B_c^+ meson

abstract:
  Encouraged by a recent observation of the B_c^+ -> B_s^0 + pi^+ decay by the
LHCb collaboration we present the meson dominance predictions for other weak
decays of the B_c^+ into B_s^0 or B^0 in the form of branching ratios to the
observed decay.


title:
Simulation study on cavity growth in ductile metal materials under
  dynamic loading

abstract:
  Cavity growth in ductile metal materials under dynamic loading is
investigated via the material point method. Two typical cavity effects in the
region subjected to rarefaction wave are identified: (i) part of material
particles flow away from the cavity in comparison to the initial loading
velocity, (ii) local regions show weaker negative or even positive pressures.
Neighboring cavities interact via coalescence of isobaric contours. The growth
of cavity under tension shows staged behaviors. After the initial slow stage,
the volume and the dimensions in both the tensile and transverse directions
show linear growth rate with time until the global tensile wave arrives at the
upper free surface. It is interesting that the growth rate in the transverse
direction is faster than that in the tensile direction. The volume growth rate
linearly increases with the initial tensile velocity. After the global tensile
wave passed the cavity, both the maximum particle velocity in the tensile
direction and the maximum particle velocity in the opposite direction increase
logarithmically with the initial tensile speed. The shock wave reflected back
from the cavity and compression wave from the free surface induce the initial
behavior of interfacial instabilities such as the Richtmyer-Meshkov
instability, which is mainly responsible for the irregularity in the morphology
of deformed cavity. The local temperatures and distribution of hot spots are
determined by the plastic work. Compared with the dynamical process, the heat
conduction is much slower.


title:
Quark deconfinement transition in neutron stars with the field
  correlator method

abstract:
  A phase of strong interacting matter with deconfined quarks is expected in
the core of massive neutron stars. In this article, we perform a study of the
hadron-quark phase transition in cold (T = 0) neutron star matter and we
calculate various structural properties of hybrid stars. For the quark phase,
we make use of an equation of state (EOS) derived with the field correlator
method (FCM) recently extended to the case of nonzero baryon density. For the
hadronic phase, we consider both pure nucleonic and hyperonic matter, and we
derive the corresponding EOS within a relativistic mean field approach. We make
use of measured neutron star masses, and particularly the mass $M = 1.97 \pm
0.04 \, M_\odot$ of PSR J1614 -2230 to constrain the values of the gluon
condensate $G_2$, which is one of the EOS parameters within the FCM. We find
that the values of $G_2$ extracted from the mass measurement of PSR J1614 -2230
are consistent with the values of the same quantity derived within the FCM from
recent lattice QCD calculations of the deconfinement transition temperature at
zero baryon chemical potential. The FCM thus provides a powerful tool to link
numerical calculations of QCD on a space-time lattice with measured neutron
star masses.


title: Fluctuations in lipid bilayers: Are they understood?

abstract:
  We review recent computer simulation studies of undulating lipid bilayers.
Theoretical interpretations of such fluctuating membranes are most commonly
based on generalized Helfrich-type elastic models, with additional
contributions of local "protrusions" and/or density fluctuations. Such models
provide an excellent basis for describing the fluctuations of tensionless
bilayers in the fluid phase at a quantitative level.
  However, this description is found to fail for membranes in the gel phase and
for membranes subject to high tensions. The fluctuations of tilted gel
membranes show a signature of the modulated ripple structure, which is a nearby
phase observed in the pretransition regime between the fluid and tilted gel
state. This complicates a quantitative analysis on mesoscopic length scales. In
the case of fluid membranes under tension, the large-wavelength fluctuation
modes are found to be significantly softer than predicted by theory.
  In the latter context, we also address the general problem of the relation
between frame tension and the fluctuation tension, which has been discussed
somewhat controversially in recent years. Simulations of very simple model
membranes with fixed area show that the fluctuations should be controlled by
the frame tension, and not by the internal tension.


title: Soliton Solutions of Fractional order KdV-Burger's Equation

abstract:
  In this article, the new exact travelling wave solutions of the time-and
space-fractional KdV-Burgers equation has been found. For this the fractional
complex transformation have been implemented to convert nonlinear partial
fractional differential equations to nonlinear ordinary differential equations,
in the sense of the Jumarie's modified Riemann-Liouville derivative.
Afterwards, the improved (G'/G)-expansion method can be implemented to
celebrate the soliton solutions of KdV-Burger's equation of fractional order.


title: Self-Consistent Field Approach for Crosslinked Copolymer Materials

abstract:
  A generalized self-consistent field approach for polymer networks with fixed
topology is developed. It is shown that the theory reproduces the localization
of crosslinks which is characteristic for gels. The theory is then used to
study the order-disorder transition in regular networks of endlinked diblock
copolymers. Compared to diblock copolymer melts, the transition is shifted
towards lower values of the incompatibility parameter $\chi$ (the Flory-
Huggins parameter). Moreover, the transition becomes strongly first order
already at the mean-field level. If stress is applied, the transition is
further shifted and finally vanishes in a critical point.


title:
Detecting multiple periodicities in observational data with the
  multifrequency periodogram - II. Frequency Decomposer, a parallelized
  time-series analysis algorithm

abstract:
  This is a parallelized algorithm performing a decomposition of a noisy time
series into a number of sinusoidal components. The algorithm analyses all
suspicious periodicities that can be revealed, including the ones that look
like an alias or noise at a glance, but later may prove to be a real variation.
After selection of the initial candidates, the algorithm performs a complete
pass through all their possible combinations and computes the rigorous
multifrequency statistical significance for each such frequency tuple. The
largest combinations that still survived this thresholding procedure represent
the outcome of the analysis.
  The parallel computing on a graphics processing unit (GPU) is implemented
through CUDA and brings a significant performance increase. It is still
possible to run FREDEC solely on CPU in the traditional single-threaded mode,
when no suitable GPU device is available.
  To verify the practical applicability of our algorithm, we apply it to an
artificial time series as well as to some real-life exoplanetary
radial-velocity data. We demonstrate that FREDEC can successfully reveal
several known exoplanets. Moreover, it detected a new $9.8$-day variation in
the Lick data for the five-planet system of 55 Cnc. It might indicate the
existence of a small sixth planet in the 3:2 commensurability with the planet
55 Cnc b, although this detection is model-dependent and still needs a detailed
verification.


title:
Long GRBs and massive stellar explosions from frame dragging around
  rotating black holes

abstract:
  The most energetic GRB-supernovae probably derive from rotating stellar mass
black holes. Based on BeppoSax data, we identify a mechanism for exploding a
remnant stellar envelope by disk winds. A specific signature is high frequency
modulations in the accompanying prompt GRB emission from dissipation in high
energy emissions along the black hole spin axis due, in part, to forced
turbulence in the inner disk or torus mediated by frame dragging. A majority of
long GRBs are found to have significant autocorrelation below 10 Hz with chirps
extending up to 1000 Hz. Their comoving Fourier spectra satisfy a power law
with index $\alpha\simeq-0.82$ up to about one hundred Hz and comoving chirp
spectra show broken power laws with $\alpha\simeq-0.65$ up to 10 Hz,
$\alpha\simeq-0.25$ up to a few hundred Hz and $\alpha\simeq0$ beyond. These
high frequency signatures are the most direct signature of long-lived
turbulence down to the ISCO of rotating black holes, pointing directly
accompanying long duration bursts in gravitational wave emission.


title:
Recent developments in the determination of the amplitude and phase of
  quantum oscillations for the linear chain of coupled orbits

abstract:
  De Haas-van Alphen oscillations are studied for Fermi surfaces (FS)
illustrating the model proposed by Pippard in the early sixties, namely the
linear chain of orbits coupled by magnetic breakdown. This FS topology is
relevant for many multiband quasi-two dimensional (q-2D) organic metals such as
$\kappa$-(BEDT-TTF)$_2$Cu(NCS)$_2$ and
$\theta$-(BEDT-TTF)$_4$CoBr$_4$(C$_6$H$_4$Cl$_2$) which are considered in
detail. Whereas the Lifshits-Kosevich model only involves a first order
development of field- and temperature-dependent damping factors, second order
terms may have significant contribution on the Fourier components amplitude for
such q-2D systems at high magnetic field and low temperature. The strength of
these second order terms depends on the relative value of the involved damping
factors, which are in turns strongly dependent on parameters such as the
magnetic breakdown field, effective masses and, most of all, effective
Land\'{e} factors. In addition, the influence of field-dependent Onsager phase
factors on the oscillation spectra is considered.


title: The magnetosphere of the close accreting PMS binary V4046 Sgr

abstract:
  V4046 Sagittarii AB is a close short-period classical T Tauri binary. It is a
circularised and synchronised system accreting from a circumbinary disk. In
2009 it was observed as part of a coordinated program involving
near-simultaneous spectropolarimetric observations with ESPaDOnS at the
Canada-France-Hawai'i Telescope and high-resolution X-ray observations with
XMM-Newton. Magnetic maps of each star were derived from Zeeman-Doppler
imaging. After briefly highlighting the most significant observational
findings, we present a preliminary 3D model of the binary magnetosphere
constructed from the magnetic maps using a newly developed binary magnetic
field extrapolation code. The large-scale fields (the dipole components) of
both stars are highly tilted with respect to their rotation axes, and their
magnetic fields are linked.


title: Fractional revivals of superposed coherent states

abstract:
  We study the dynamics of superposed wave packets in a specific nonlinear
Hamiltonian which models the wave packet propagation in Kerr-like media and the
dynamics of Bose-Einstein condensates. We show the dependence of initial wave
packet superposition on fractional revival times using analysis based on the
expectation values, R\'{e}nyi entropy and Wigner function. We also show how the
selective identification of fractional revivals using moments of appropriate
observables depends on the number of wave packets present in the initial state.


title: Algebraic independence and normality of the values of Mahler's functions

abstract:
  The main purpose of this article is to provide new results on algebraic
independence of values of Mahler functions and their generalizations.
Simultaneously, we establish new measures of algebraic independence for these
values. Among the other things, we provide a measure of algebraic independence
for values of Mahler's functions at complex transcendental points, a result of
type which has never appeared in the literature in the past.
  As an example of application of our new measures of algebraic independence,
we prove that a Mahler number does not belong to the class $U$ in Mahler's
classification. Also, our results imply new examples, for $n\geq 1$ arbitrarily
large, of sets $\left(\theta_1,\dots,\theta_n\right)\in\mathbb{R}^n$ normal in
the sense of G.~Chudnovsky (1980).


title:
Nature of the magnetic ground state in the mixed valence compound
  CeRuSn: a single-crystal study

abstract:
  We report on detailed low temperature measurements of the magnetization, the
specific heat and the electrical resistivity on high quality CeRuSn single
crystals. The compound orders antiferromagnetically at $T_{\rm N} = 2.8$ K with
the Ce$^{3+}$ ions locked within the $a-c$ plane of the monoclinic structure.
Magnetization shows that below $T_{\rm N}$ CeRuSn undergoes a metamagnetic
transition when applying a magnetic field of 1.5 and 0.8 T along the $a$ and
$c$--axis, respectively. This transition manifests in a tremendous negative
jump of $\sim 25$% in the magnetoresistance. The value of the saturated
magnetization along the easy magnetization direction ($c$--axis) and the
magnetic entropy above $T_{\rm N}$ derived from specific heat data correspond
to the scenario where only one third of the Ce ions in the compound being
trivalent and carrying a stable Ce$^{3+}$ magnetic moment, whereas the other
two thirds of the Ce ions are in a nonmagnetic tetravalent and/or mixed valence
state. This is consistent with the low temperature CeRuSn crystal structure
i.\,e.\,, a superstructure consisting of three unit cells of the CeCoAl-type
piled up along the $c$--axis, and in which the Ce$^{3+}$ ions are characterized
by large distances from the Ru ligands while the Ce-Ru distances of the other
Ce ions are much shorter causing a strong 4{\it f}-ligand hybridization and
hence leading to tetravalent and/or mixed valence Ce ions.


title:
Nonlinear evolution of the tidal elliptical instability in gaseous
  planets and stars

abstract:
  Tidally distorted rotating stars and gaseous planets are subject to a
well-known linear fluid instability -- the elliptical instability. It has been
proposed that this instability might drive enough energy dissipation to solve
the long-standing problem of the origin of tidal dissipation in stars and
planets. But the nonlinear outcome of the elliptical instability has yet to be
investigated in the parameter regime of interest, and the resulting turbulent
energy dissipation has not yet been quantified. We do so by performing three
dimensional hydrodynamical simulations of a small patch of a tidally deformed
fluid planet or star subject to the elliptical instability. We show that when
the tidal deformation is weak, the nonlinear outcome of the instability leads
to the formation of long-lived columnar vortices aligned with the axis of
rotation. These vortices shut off the elliptical instability, and the net
result is insufficient energy dissipation to account for tidal dissipation.
However, further work is required to account for effects neglected here,
including magnetic fields, turbulent convection, and realistic boundary
conditions.


title:
Nonlinear evolution of the elliptical instability in the presence of
  weak magnetic fields

abstract:
  We investigate whether the elliptical instability is important for tidal
dissipation in gaseous planets and stars. In a companion paper, we found that
the conventional elliptical instability results in insufficient dissipation
because it produces long-lived vortices that then quench further instability.
Here, we study whether the addition of a magnetic field prevents those vortices
from forming, and hence leads to enhanced dissipation. We present results from
magnetohydrodynamical simulations that evolve the elliptical instability in a
local patch of a rotating planet or star, in the presence of a weak magnetic
field. We find that magnetic fields do indeed prevent vortices from forming,
and hence greatly enhance the steady state dissipation rate. In addition, the
resulting turbulence acts as a small-scale dynamo, amplifying the initially
weak field. The inferred tidal dissipation is potentially important at short
orbital periods. For example, it can circularise hot Jupiters with orbital
periods shorter than 2.5 days, and synchronise their spins with their orbits
out to 6 days. However, it appears unable to account for the hot Jupiters that
appear to have been circularised out to six to ten day orbital periods. It also
cannot account for the inferred circularisation of many close binary stars.


title:
Wegner estimate and localization for alloy-type models with
  sign-changing exponentially decaying single-site potentials

abstract:
  We study Schr\"odinger operators on $L^2 (\RR^d)$ and $\ell^2(\ZZ^d)$ with a
random potential of alloy-type. The single-site potential is assumed to be
exponentially decaying but not necessarily of fixed sign. In the continuum
setting we require a generalized step-function shape. Wegner estimates are
bounds on the average number of eigenvalues in an energy interval of finite box
restrictions of these types of operators. In the described situation a Wegner
estimate which is polynomial in the volume of the box and linear in the size of
the energy interval holds. We apply the established Wegner estimate as an
ingredient for a localization proof via multiscale analysis.


title: ADI schemes for pricing American options under the Heston model

abstract:
  In this paper a simple, effective adaptation of Alternating Direction
Implicit (ADI) time discretization schemes is proposed for the numerical
pricing of American-style options under the Heston model via a partial
differential complementarity problem. The stability and convergence of the new
methods are extensively investigated in actual, challenging applications. In
addition a relevant theoretical result is proved.


title:
Turing Instability in Reaction-Diffusion Systems with a Single Diffuser:
  Characterization Based on Root Locus

abstract:
  Cooperative behaviors arising from bacterial cell-to-cell communication can
be modeled by reaction-diffusion equations having only a single diffusible
component. This paper presents the following three contributions for the
systematic analysis of Turing instability in such reaction-diffusion systems.
(i) We first introduce a unified framework to formulate the reaction-diffusion
system as an interconnected multi-agent dynamical system. (ii) Then, we
mathematically classify biologically plausible and implausible Turing
instabilities and characterize them by the root locus of each agent's dynamics,
or the local reaction dynamics. (iii) Using this characterization, we derive
analytic conditions for biologically plausible Turing instability, which
provide useful guidance for the design and the analysis of biological networks.
These results are demonstrated on an extended Gray-Scott model with a single
diffuser.


title:
An introduction to multivariate Krawtchouk polynomials and their
  applications

abstract:
  Orthogonal polynomials for the multinomial distribution m(x, p) of N balls
dropped into d boxes (box i has probability p(i)) are called multivariate
Krawtchouk polynomials. This paper gives an introduction to their properties,
collections of natural Markov chains which they explicitly diagonalize and
associated bivariate multinomial distributions.


title:
Non-Asymptotic Convergence Analysis of Inexact Gradient Methods for
  Machine Learning Without Strong Convexity

abstract:
  Many recent applications in machine learning and data fitting call for the
algorithmic solution of structured smooth convex optimization problems.
Although the gradient descent method is a natural choice for this task, it
requires exact gradient computations and hence can be inefficient when the
problem size is large or the gradient is difficult to evaluate. Therefore,
there has been much interest in inexact gradient methods (IGMs), in which an
efficiently computable approximate gradient is used to perform the update in
each iteration. Currently, non-asymptotic linear convergence results for IGMs
are typically established under the assumption that the objective function is
strongly convex, which is not satisfied in many applications of interest; while
linear convergence results that do not require the strong convexity assumption
are usually asymptotic in nature. In this paper, we combine the best of these
two types of results and establish---under the standard assumption that the
gradient approximation errors decrease linearly to zero---the non-asymptotic
linear convergence of IGMs when applied to a class of structured convex
optimization problems. Such a class covers settings where the objective
function is not necessarily strongly convex and includes the least squares and
logistic regression problems. We believe that our techniques will find further
applications in the non-asymptotic convergence analysis of other first-order
methods.