title: Can Facial Uniqueness be Inferred from Impostor Scores?

abstract:
  In Biometrics, facial uniqueness is commonly inferred from impostor
similarity scores. In this paper, we show that such uniqueness measures are
highly unstable in the presence of image quality variations like pose, noise
and blur. We also experimentally demonstrate the instability of a recently
introduced impostor-based uniqueness measure of [Klare and Jain 2013] when
subject to poor quality facial images.


title:
Multiview Navigation based on Extended Layered Depth Image
  Representation

abstract:
  Emerging applications in multiview streaming look for providing interactive
navigation services to video players. The user can ask for information from any
viewpoint with a minimum transmission delay. The purpose is to provide user
with as much information as possible with least number of redundancies. The
recent concept of navigation segment representation consists of regrouping a
given number of viewpoints in one signal and transmitting them to the users
according to their navigation path. The question of the best description
strategy of these navigation segments is however still open. In this paper, we
propose to represent and code navigation segments by a method that extends the
recent layered depth image (LDI) format. It consists of describing the scene
from a viewpoint with multiple images organized in layers corresponding to the
different levels of occluded objects. The notion of extended LDI comes from the
fact that the size of this image is adapted to take into account the sides of
the scene also, in contrary to classical LDI. The obtained results show a
significant rate-distortion gain compared to classical multiview compression
approaches in navigation scenario.


title: Derived functor modules, dual pairs and $U(\mathfrak{g})^K$-actions

abstract:
  Derived functors (or Zuckerman functors) play a very important role in the
study of unitary representations of real reductive groups. These functors are
usually applied on highest weight modules in the so-called good range and the
theory is well-understood. On the other hand, there were several studies on the
irreducibility and unitarizability, in which derived functors are applied to
singular modules. See Enright et al. (Acta. Math. 1985), for example. In this
article, we apply derived functors to certain modules arising from the
formalism of local theta lifting, and investigate the irreducible sub-quotients
of resulting modules. The key technique is to understand
$U(\mathfrak{g})^K$-actions in the setting of a see-saw pair. Our results
strongly suggest that derived functor constructions are compatible with local
theta lifting.


title:
The violation of the No-Hair Conjecture in four-dimensional ungauged
  Supergravity

abstract:
  By choosing a particular, String Theory inspired, Special K\"ahler manifold,
we are able to find a N=2 four-dimensional ungauged Supergravity model that
contains supersymmetric black hole solutions that violate the folk uniqueness
theorems that are expected to hold in ungauged Supergravity. The black hole
solutions are regular in the sense that they have a positive mass and a unique
physical singularity hidden by an event horizon. In contradistinction to most
examples already known in the literature, we find our solutions in a theory
without scalar potential, gaugings or higher order curvature terms.


title:
Fast distributed phononic band-structure calculations through a GPU
  accelerated mixed-variational formulation

abstract:
  In this paper we present a Graphical Processing Unit accelerated mixed
variational formulation for fast phononic band-structure calculation of
arbitrarily complex unit cells and report speed gains of a hundred fold over
unoptimized serial cpu computations. To the author's knowledge this is the
first application of gpu computing to a non-FE/FDTD bandstructure algorithm.
The formulation is presented in a form which is applicable to 1-, 2-, and 3-D
cases. However, in this paper we concentrate on optimizing the formulation
within the paradigm of gpu computing, presenting results for 2-D unit cells. We
describe the application of the formulation with a long term view towards
highly efficient and massively distributed band-structure algorithms suitable
for tackling optimization and inverse problems. We report that the accurate
band-structure evaluation over the boundary of the Irreducible Brillouin Zone
(IBZ) for the first 18 phononic branches of a complex 2-D unit cell (with 1132
different phases) can be achieved in less than 20 seconds on a regular desktop.
For a simpler unit cell, the first few phononic branches are calculated in less
than 2.5 seconds on the same system. The scheme presented in this paper,
therefore, represents considerable savings in the computational costs of
phononic band-structures.


title:
Analysis of High Cadence In-Situ Solar Wind Ionic Composition Data Using
  Wavelet Power Spectra Confidence Levels

abstract:
  The variability inherent in solar wind composition has implications for the
variability of the physical conditions in its coronal source regions, providing
constraints on models of coronal heating and solar wind generation. We present
a generalized prescription for constructing a wavelet power significance
measure (confidence level) for the purpose of characterizing the effects of
missing data in high cadence solar wind ionic composition measurements. We
describe the data gaps present in the 12-minute ACE/SWICS observations of
O7+/O6+ during 2008. The decomposition of the in-situ observations into a `good
measurement' and a `no measurement' signal allows us to evaluate the
performance of a filler signal, i.e., various prescriptions for filling the
data gaps. We construct Monte Carlo simulations of synthetic O7+/O6+
composition data and impose the actual data gaps that exist in the observations
in order to investigate two different filler signals: one, a linear
interpolation between neighboring good data points, and two, the constant mean
value of the measured data. Applied to these synthetic data plus filler signal
combinations, we quantify the ability of the power spectra significance level
procedure to reproduce the ensemble-averaged time-integrated wavelet power per
scale of an ideal case, i.e. the synthetic data without imposed data gaps.
Finally, we present the wavelet power spectra for the O7+/O6+ data using the
confidence levels derived from both the Mean Value and Linear Interpolation
data gap filling signals and discuss the results.


title:
TARK 2013 - Proceedings of the 14. Conference on Theoretical Aspects of
  Rationality and Knowledge

abstract:
  The biannual TARK conferences bring together researchers from a wide variety
of fields sharing a common interest in reasoning about rationality and
knowledge. The impact of this tradition, going back to 1986, is apparent in
many of today's research trends and in the growth of an intellectual community
beyond traditional disciplinary boundaries. This volume documents the 14th TARK
conference, held at the Institute of Mathematical Sciences, Chennai, India on
January 7 to 9, 2013. It includes 18 contributed talks, 8 poster presentations,
and 3 invited talks given at the conference. Like earlier volumes in this
series, it gives a sense of the state of the art in studies of knowledge and
rationality in areas such as game theory, decision theory, belief revision,
language analysis, and computation. It should be of value to researchers,
teachers, and students.


title: The Frequent Paucity of Trivial Strings

abstract:
  A 1976 theorem of Chaitin can be used to show that arbitrarily dense sets of
lengths n have a paucity of trivial strings (only a bounded number of strings
of length n having trivially low plain Kolmogorov complexities). We use the
probabilistic method to give a new proof of this fact. This proof is much
simpler than previously published proofs, and it gives a tighter paucity bound.


title: Conjugacy classes and characters for extensions of finite groups

abstract:
  Let $H$ be an extension of a finite group $Q$ by a finite group $G$. Inspired
by the results of duality theorems for \'etale gerbes on orbifolds, we describe
the number of conjugacy classes of $H$ that maps to the same conjugacy class of
$Q$. Furthermore, we prove a generalization of the orthogonality relation
between characters of $G$.


title: Infrared evidence of a Slater metal-insulator transition in NaOsO3

abstract:
  The magnetically driven metal-insulator transition (MIT) was predicted by
Slater in the fifties. Here a long-range antiferromagnetic (AF) order can open
up a gap at the Brillouin electronic band boundary regardless of the Coulomb
repulsion magnitude. However, while many low-dimensional organic conductors
display evidence for an AF driven MIT, in three-dimensional (3D) systems the
Slater MIT still remains elusive. We employ terahertz and infrared spectroscopy
to investigate the MIT in the NaOsO3 3D antiferromagnet. From the optical
conductivity analysis we find evidence for a continuous opening of the energy
gap, whose temperature dependence can be well described in terms of a second
order phase transition. The comparison between the experimental Drude spectral
weight and the one calculated through Local Density Approximation (LDA) shows
that electronic correlations play a limited role in the MIT. All the
experimental evidence demonstrates that NaOsO3 is the first known 3D Slater
insulator.


title: Landau damping in a collisionless dipolar Bose gas

abstract:
  We present a theory for the Landau damping of low energy quasi-particles in a
collisionless, quasi-2D dipolar Bose gas and produce expressions for the
damping rate in uniform and non-uniform systems. Using simple energy-momentum
conservation arguments, we show that in the homogeneous system, the nature of
the low energy dispersion in a dipolar Bose gas severely inhibits Landau
damping of long wave-length excitations. For a gas with contact and dipolar
interactions, the damping rate for phonons tends to decrease with increasing
dipolar interactions; for strong dipole-dipole interactions, phonons are
virtually undamped over a broad range of temperature. The damping rate for
maxon-roton excitations is found to be significantly larger than the damping
rate for phonons.


title: Single and double diffractive prompt photon production at the LHC

abstract:
  In this contribution we study for the first time the prompt photon production
in single and double diffractive processes considering the resolved Pomeron
model. We estimate the rapidity and transverse momentum dependence of the cross
section for the production of two photons and of a photon and a jet. We show
that these processes are sensitive to the pomeron structure. In contrast with
the dijet and heavy quark production, which are dominated by gluon-gluon
interactions, in prompt photon production, Compton like processes are dominant
for single photon plus jet events. This gives a unique oportunity to constrain
the quark distribution in the Pomeron. The results are obtained for the LHC
energy.


title: Perturbative series and the 1/N expansion for the QED \beta-function

abstract:
  A comparison of the perturbative series and the 1/N expansion for the QED
renormalization group \beta-function in the Minimal Subtraction scheme is
performed. The good agreement between two expansions is found which proves that
the MS \beta-function is under perfect perturbative control.


title: The electromagnetic form factor of the pion: Results from the lattice

abstract:
  This review contains an overview over recent results for the electromagnetic
iso-vector form factor of the pion obtained in lattice QCD with dynamical
fermions. Particular attention is given to the extrapolation to the physical
point and an easy assessment of the control over the main systematic effects by
imposing quality criteria and an associated sign code, similar to the ones used
by the FLAG working group. Also included is a brief discussion of recent
developments and future challenges concerning the accurate extraction of the
form factor in the lattice framework.


title: The local structure theorem for real spherical varieties

abstract:
  Let $G$ be an algebraic real reductive group and $Z$ a real spherical
$G$-variety, that is, it admits an open orbit for a minimal parabolic subgroup
$P$. We prove a local structure theorem for $Z$. In the simplest case where $Z$
is homogeneous, the theorem provides an isomorphism of the open $P$-orbit with
a bundle $Q \times_L S$. Here $Q$ is a parabolic subgroup with Levi
decomposition $LU$, and $S$ is a homogeneous space for a quotient $D=L/L_n$ of
$L$, where $L_n$ is normal in $L$, such that $D$ is compact modulo center.


title: Robust bounds on risk-sensitive functionals via Renyi divergence

abstract:
  We extend the duality between exponential integrals and relative entropy to a
variational formula for exponential integrals involving the Renyi divergence.
This formula characterizes the dependence of risk-sensitive functionals and
related quantities determined by tail behavior to perturbations in the
underlying distributions, in terms of the Renyi divergence. The
characterization gives rise to upper and lower bounds that are meaningful for
all values of a large deviation scaling parameter, allowing one to quantify in
explicit terms the robustness of risk-sensitive costs. As applications we
consider problems of uncertainty quantification when aspects of the model are
not fully known, as well their use in bounding tail properties of an
intractable model in terms of a tractable one.


title: Linear Stability Analysis of Dynamical Quadratic Gravity

abstract:
  We perform a linear stability analysis of dynamical, quadratic gravity in the
high-frequency, geometric optics approximation. This analysis is based on a
study of gravitational and scalar modes propagating on spherically-symmetric
and axially-symmetric, vacuum solutions of the theory. We find dispersion
relations that do no lead to exponential growth of the propagating modes,
suggesting the theory is linearly stable on these backgrounds. The modes are
found to propagate at subluminal and superluminal speeds, depending on the
propagating modes' direction relative to the background geometry, just as in
dynamical Chern-Simons gravity.


title: Reducts of structures and maximal-closed permutation groups

abstract:
  Answering a question of Junker and Ziegler, we construct a countable first
order structure which is not omega-categorical, but does not have any proper
non-trivial reducts, in either of two senses (model-theoretic, and
group-theoretic). We also construct a strongly minimal set which is not
omega-categorical but has no proper non-trivial reducts in the model-theoretic
sense.


title:
The Integrable Bootstrap Program at Large N and its Applications in
  Gauge Theory

abstract:
  We present results for the large-$N$ limit of the (1+1)-dimensional principal
chiral sigma model. This is an asymptotically-free $N\times N$ matrix-valued
field with massive excitations. All the form factors and the exact correlation
functions of the Noether-current operator and the energy-momentum tensor are
found, from Smirnov's form-factor axioms. We consider (2+1)-dimensional
$SU(\infty)$ Yang-Mills theory as an array of principal chiral models with a
current-current interaction. We discuss how to use our new form factors to
calculate physical quantities in this gauge theory.


title:
Universal microscopic correlation functions for products of truncated
  unitary matrices

abstract:
  We investigate the spectral properties of the product of $M$ complex
non-Hermitian random matrices that are obtained by removing $L$ rows and
columns of larger unitary random matrices uniformly distributed on the group
${\rm U}(N+L)$. Such matrices are called truncated unitary matrices or random
contractions. We first derive the joint probability distribution for the
eigenvalues of the product matrix for fixed $N,\ L$, and $M$, given by a
standard determinantal point process in the complex plane. The weight however
is non-standard and can be expressed in terms of the Meijer G-function. The
explicit knowledge of all eigenvalue correlation functions and the
corresponding kernel allows us to take various large $N$ (and $L$) limits at
fixed $M$. At strong non-unitarity, with $L/N$ finite, the eigenvalues condense
on a domain inside the unit circle. At the edge and in the bulk we find the
same universal microscopic kernel as for a single complex non-Hermitian matrix
from the Ginibre ensemble. At the origin we find the same new universality
classes labelled by $M$ as for the product of $M$ matrices from the Ginibre
ensemble. Keeping a fixed size of truncation, $L$, when $N$ goes to infinity
leads to weak non-unitarity, with most eigenvalues on the unit circle as for
unitary matrices. Here we find a new microscopic edge kernel that generalizes
the known results for M=1. We briefly comment on the case when each product
matrix results from a truncation of different size $L_j$.


title: Geometry of the Riemann Zeta Function

abstract:
  The individual terms of the series representing the Riemann zeta function are
examined geometrically from their accumulated plot in the complex plane.
Symmetry is identified and determined mathematically for comparison with more
traditional results of analytic number theory. A new interpretation of analytic
continuation allows a construction, based on the limacon, which shows the
conditions under which zeros can occur. The special importance of prime steps
in the decrease of the real part from 1 to 0 when zeta equals zero is shown.
Discussion of bounds and extension to generalized zeta functions are included.


title:
Variance Based Scheduling Algorithm with Relay Selection and Resource
  Allocation in Cooperative OFDMA Networks

abstract:
  Nowadays the radio interface of several standards is enhanced with advanced
technologies such as OFDMA and extension technology such as relay. By using
those promising transmission technology for the next generation wireless
communications, scheduling problem becomes more crucial and challenging. In our
work, we aim to maximize the overall system capacity while selecting the most
suitable relay station under fairness constraint among both users and relay
station by proposing a Gap- based scheduling. This one considers the channel
state information and the unbalanced rate capacity of the two hops links.
Simulations results show the effectiveness of our approach in terms of fairness
and the overall system performance.


title: Some Remarks on Lower Bounds for Queue Machines (Preliminary Report)

abstract:
  We first give an improved lower bound for the deterministic online simulation
of tapes or pushdown stores by queues. Then we inspect some proofs in a
classical work on queue machines in the area of Formal Languages and outline
why a main argument in the proofs is incomplete. Based on descriptional
complexity, we show the intuition behind the argument to be correct.


title: Inflationary Attractors and their Measures

abstract:
  Several recent misconceptions about the measure problem in inflation and the
nature of inflationary attractors are addressed. We show that within the
Hamiltonian system of flat Friedmann-Lema\^itre-Robertson-Walker cosmology
coupled to a massive scalar field, the focussing of the Liouville measure on
attractor solutions is brought about by a spread in a gauge degree of freedom -
the spatial volume. Using this we show how the Liouville measure formulated on
a surface of constant Hubble rate induces a probability distribution function
on surfaces of other Hubble rates, and the attractor behaviour is seen through
the focussing of this function on a narrow range of physical observables. One
can conclude then that standard techniques from Hamiltonian dynamics suffice to
provide a satisfactory description of attractor solutions and the measure
problem.
  Updated to match published version.


title: Investigating magnetic activity of F stars with the it Kepler mission

abstract:
  The dynamo process is believed to drive the magnetic activity of stars like
the Sun that have an outer convection zone. Large spectroscopic surveys showed
that there is a relation between the rotation periods and the cycle periods:
the longer the rotation period is, the longer the magnetic activity cycle
period will be. We present the analysis of F stars observed by Kepler for which
individual p modes have been measure and with surface rotation periods shorter
than 12 days. We defined magnetic indicators and proxies based on photometric
observations to help characterise the activity levels of the stars. With the
Kepler data, we investigate the existence of stars with cycles (regular or
not), stars with a modulation that could be related to magnetic activity, and
stars that seem to show a flat behaviour.


title: Ensemble Analysis of Adaptive Compressed Genome Sequencing Strategies

abstract:
  Acquiring genomes at single-cell resolution has many applications such as in
the study of microbiota. However, deep sequencing and assembly of all of
millions of cells in a sample is prohibitively costly. A property that can come
to rescue is that deep sequencing of every cell should not be necessary to
capture all distinct genomes, as the majority of cells are biological
replicates. Biologically important samples are often sparse in that sense. In
this paper, we propose an adaptive compressed method, also known as distilled
sensing, to capture all distinct genomes in a sparse microbial community with
reduced sequencing effort. As opposed to group testing in which the number of
distinct events is often constant and sparsity is equivalent to rarity of an
event, sparsity in our case means scarcity of distinct events in comparison to
the data size. Previously, we introduced the problem and proposed a distilled
sensing solution based on the breadth first search strategy. We simulated the
whole process which constrained our ability to study the behavior of the
algorithm for the entire ensemble due to its computational intensity. In this
paper, we modify our previous breadth first search strategy and introduce the
depth first search strategy. Instead of simulating the entire process, which is
intractable for a large number of experiments, we provide a dynamic programming
algorithm to analyze the behavior of the method for the entire ensemble. The
ensemble analysis algorithm recursively calculates the probability of capturing
every distinct genome and also the expected total sequenced nucleotides for a
given population profile. Our results suggest that the expected total sequenced
nucleotides grows proportional to $\log$ of the number of cells and
proportional linearly with the number of distinct genomes.


title: Interpreting the Ionization Sequence in AGN Emission-Line Spectra

abstract:
  We investigate the physical cause of the great range in the ionization level
seen in the spectra of narrow lined active galactic nuclei (AGN). Mean field
independent component analysis identifies examples of individual SDSS galaxies
whose spectra are not dominated by emission due to star formation (SF), which
we designate as AGN. We assembled high S/N ratio composite spectra of a
sequence of these AGN defined by the ionization level of their narrow-line
regions (NLR), extending down to very low-ionization cases. We used a local
optimally emitting cloud (LOC) model to fit emission-line ratios in this AGN
sequence. These included the weak lines that can be measured only in the
co-added spectra, providing consistency checks on strong line diagnostics.
After integrating over a wide range of radii and densities our models indicate
that the radial extent of the NLR is the major parameter in determining the
position of high to moderate ionization AGN along our sequence, providing a
physical interpretation for their systematic variation. Higher ionization AGN
contain optimally emitting clouds that are more concentrated towards the
central continuum source than in lower ionization AGN. Our LOC models indicate
that for the objects that lie on our AGN sequence, the ionizing luminosity is
anticorrelated with the NLR ionization level, and hence anticorrelated with the
radial concentration and physical extent of the NLR. A possible interpretation
that deserves further exploration is that the ionization sequence might be an
age sequence where low ionization objects are older and have systematically
cleared out their central regions by radiation pressure. We consider that our
AGN sequence instead represents a mixing curve of SF and AGN spectra, but argue
that while many galaxies do have this type of composite spectra, our AGN
sequence appears to be a special set of objects with negligible SF excitation.


title: There are no socialist primes less than 10^9

abstract:
  There are no primes $p$ with $5<p<10^{9}$ for which $2!, 3!, \ldots, (p-1)!$
are all distinct modulo $p$; it is conjectured that there are no such primes.


title: Visualizing overtwisted discs in open books

abstract:
  We give an alternative proof of a theorem of Honda-Kazez-Mati\'c that every
non-right-veering open book supports an overtwisted contact structure. We also
study two types of examples that show how overtwisted discs are embedded
relative to right-veering open books.


title: Utility-based Decision-making in Distributed Systems Modelling

abstract:
  We consider a calculus of resources and processes as a basis for modelling
decision-making in multi-agent systems. The calculus represents the regulation
of agents' choices using utility functions that take account of context.
Associated with the calculus is a (Hennessy Milner-style) context sensitive
modal logic of state. As an application, we show how a notion of `trust domain'
can be defined for multi-agent systems.


title: On the Complexity of Dynamic Epistemic Logic

abstract:
  Although Dynamic Epistemic Logic (DEL) is an influential logical framework
for representing and reasoning about information change, little is known about
the computational complexity of its associated decision problems. In fact, we
only know that for public announcement logic, a fragment of DEL, the
satisfiability problem and the model-checking problem are respectively
PSPACE-complete and in P. We contribute to fill this gap by proving that for
the DEL language with event models, the model-checking problem is,
surprisingly, PSPACE-complete. Also, we prove that the satisfiability problem
is NEXPTIME-complete. In doing so, we provide a sound and complete tableau
method deciding the satisfiability problem.


title: The Shape of Reactive Coordination Tasks

abstract:
  This paper studies the interaction between knowledge, time and coordination
in systems in which timing information is available. Necessary conditions are
given for the causal structure in coordination problems consisting of
orchestrating a set of actions in a manner that satisfies a variety of temporal
ordering assumptions. Results are obtained in two main steps: A specification
of coordination is shown to require epistemic properties, and the causal
structure required to obtain these properties is characterised via "knowledge
gain" theorems. A new causal structure called a centibroom structure is
presented, generalising previous causal structures for this model. It is shown
to capture coordination tasks in which a sequence of clusters of events is
performed in linear order, while within each cluster all actions must take
place simultaneously. This form of coordination is shown to require the agents
to gain a nested common knowledge of particular facts, which in turn requires a
centibroom. Altogether, the results presented provide a broad view of the
causal shape underlying partially ordered coordinated actions. This, in turn,
provides insight into and can enable the design of efficient solutions to the
coordination tasks in question.


title: Language-based Games

abstract:
  We introduce language-based games, a generalization of psychological games
[6] that can also capture reference-dependent preferences [7]. The idea is to
extend the domain of the utility function to situations, maximal consistent
sets in some language. The role of the underlying language in this framework is
thus particularly critical. Of special interest are languages that can express
only coarse beliefs [9]. Despite the expressive power of the approach, we show
that it can describe games in a simple, natural way. Nash equilibrium and
rationalizability are generalized to this setting; Nash equilibrium is shown
not to exist in general, while the existence of rationalizable strategies is
proved under mild conditions.


title: Defeasible Modalities

abstract:
  Nonmonotonic logics are usually characterized by the presence of some notion
of 'conditional' that fails monotonicity. Research on nonmonotonic logics is
therefore largely concerned with the defeasibility of argument forms and the
associated normality (or abnormality) of its constituents. In contrast,
defeasible modes of inference aim to formalize the defeasible aspects of modal
notions such as actions, obligations and knowledge. In this work we enrich the
standard possible worlds semantics with a preference ordering on worlds in
Kripke models. The resulting family of modal logics allow for the elegant
expression of defeasible modalities. We also propose a tableau calculus which
is sound and complete with respect to our preferential semantics.


title: Knowledge, Awareness, and Bisimulation

abstract:
  We compare different epistemic notions in the presence of awareness of
propositional variables: the logics of implicit knowledge (in which explicit
knowledge is definable), explicit knowledge, and speculative knowledge.
Different notions of bisimulation are suitable for these logics. We provide
correspondence between bisimulation and modal equivalence on image-finite
models for these logics. The logic of speculative knowledge is equally
expressive as the logic of explicit knowledge, and the logic of implicit
knowledge is more expressive than both. We also provide axiomatizations for the
three logics -- only the one for speculative knowledge is novel. Then we move
to the study of dynamics by recalling action models incorporating awareness. We
show that any conceivable change of knowledge or awareness can be modelled in
this setting, we give a complete axiomatization for the dynamic logic of
implicit knowledge. The dynamic versions of all three logics are, surprising,
equally expressive.


title: Bounded rationality in a dynamic alternate game

abstract:
  From the standpoint of game theory, dominoes is a game that has not received
much attention (specially the variety known as draw). It is usually thought
that this game is already solved, given general results in game theory.
However, the determination of equilibria is not feasible for the general case
because of the well known problem of node explosion in the tree expressing the
game. We propose a new model based in limited forecast as a kind of bounded
rationality for dynamic alternate games.


title: Domains of discontinuity for almost-Fuchsian Groups

abstract:
  An almost-Fuchsian group is a quasi-Fuchsian group such that the quotient
hyperbolic manifold contains a closed incompressible minimal surface with
principal curvatures contained in (-1,1). We show that the domain of
discontinuity of an almost-Fuchsian group contains many balls of a fixed
spherical radius in the visual boundary of hyperbolic 3-space. This yields a
necessary condition for a quasi-Fuchsian group to be almost-Fuchsian which
involves only conformal geometry. As an application, we prove that there are no
doubly-degenerate geometric limits of almost-Fuchsian groups.


title: How To Place a Point to Maximize Angles

abstract:
  We describe a randomized algorithm that, given a set $P$ of points in the
plane, computes the best location to insert a new point $p$, such that the
Delaunay triangulation of $P\cup\{p\}$ has the largest possible minimum angle.
The expected running time of our algorithm is at most cubic, improving the
roughly quartic time of the best previously known algorithm. It slows down to
slightly super-cubic if we also specify a set of non-crossing segments with
endpoints in $P$ and insist that the triangulation respect these segments,
i.e., is the constrained Delaunay triangulation of the points and segments.


title: Timely Common Knowledge

abstract:
  Coordinating activities at different sites of a multi-agent system typically
imposes epistemic constraints on the participants. Specifying explicit bounds
on the relative times at which actions are performed induces combined temporal
and epistemic constraints on when agents can perform their actions. This paper
characterises the interactive epistemic state that arises when actions must
meet particular temporal constraints. The new state, called timely common
knowledge, generalizes common knowledge, as well as other variants of common
knowledge. While known variants of common knowledge are defined in terms of a
fixed point of an epistemic formula, timely common knowledge is defined in
terms of a vectorial fixed point of temporal-epistemic formulae. A general
class of coordination tasks with timing constraints is defined, and timely
common knowledge is used to characterise both solvability and optimal solutions
of such tasks. Moreover, it is shown that under natural conditions, timely
common knowledge is equivalent to an infinite conjunction of temporal-epistemic
formulae, in analogy to the popular definition of common knowledge.


title: Quantization of Whitney functions and reduction

abstract:
  For a possibly singular subset of a regular Poisson manifold we construct a
deformation quantization of its algebra of Whitney functions. We then extend
the construction of a deformation quantization to the case where the underlying
set is a subset of a not necessarily regular Poisson manifold which can be
written as the quotient of a regular Poisson manifold on which a compact Lie
group acts freely by Poisson maps. Finally, if the quotient Poisson manifold is
regular as well, we show a "quantization commutes with reduction" type result.
For the proofs, we use methods stemming from both singularity theory and
Poisson geometry.


title: Ceteris Paribus Structure in Logics of Game Forms

abstract:
  The article introduces a ceteris paribus modal logic interpreted on the
equivalence classes induced by sets of propositional atoms. This logic is used
to embed two logics of agency and games, namely atemporal STIT and the
coalition logic of propositional control (CL-PC). The embeddings highlight a
common ceteris paribus structure underpinning the key modal operators of both
logics, they clarify the relationship between STIT and CL-PC, and enable the
transfer of complexity results to the ceteris paribus logic.


title: Testing assumptions and predictions of star-formation theories

abstract:
  (Abridged). We present numerical simulations of isothermal, MHD, supersonic
turbulence, designed to test various hypotheses frequently assumed in star
formation(SF) theories. We consider three simulations, each with a different
combination of physical size, rms sonic Mach number, and Jeans parameter, but
chosen as to give the same value of the virial parameter and to conform with
Larson's scaling relations. As in the non-magnetic case: we find no
simultaneously subsonic and super-Jeans structures in our MHD simulations. We
find that the fraction of small-scale super-Jeans structures increases when
self gravity is turned on, and that the production of gravitationally unstable
dense cores by turbulence alone is very low. This implies that self-gravity is
in general necessary not only to induce the collapse of Jeans-unstable cores,
but also to form them. We find that denser regions tend to have more negative
values of the velocity divergence, implying a net inwards flow towards the
regions' centers. We compare the results from our simulations with the
predictions from the recent SF theories by Krumholz & McKee, Padoan & Nordlund,
and Hennebelle & Chabrier, using the expressions recently provided by Federrath
& Klessen. We find that none of these theories reproduces the dependence of the
SFEff with Ms observed in our simulations in the MHD case. The SFEff predicted
by the theories ranges between half and one order of magnitude larger than what
we observe in the simulations in both the HD and the MHD cases. We conclude
that the type of flow used in simulations like the ones presented here and
assumed in recent SF theories, may not correctly represent the flow within
actual clouds, and that theories that assume it does may be missing a
fundamental aspect of the flow. We suggest that a more realistic regime may be
that of hierarchical gravitational collapse.


title: Deludedly Agreeing to Agree

abstract:
  We study conditions relating to the impossibility of agreeing to disagree in
models of interactive KD45 belief (in contrast to models of S5 knowledge, which
are used in nearly all the agreements literature). We show that even when the
truth axiom is not assumed it turns out that players will find it impossible to
agree to disagree under fairly broad conditions.


title:
Transport in quenched disorder: light diffusion in strongly
  heterogeneous turbid media

abstract:
  We present a theoretical and experimental study of light transport in
disordered media with strongly heterogeneous distribution of scatterers formed
via non-scattering regions. Step correlations induced by quenched disorder are
found to prevent diffusivity from diverging with increasing heterogeneity
scale, contrary to expectations from annealed models. Spectral diffusivity is
measured for a porous ceramic where nanopores act as scatterers and macropores
render their distribution heterogeneous. Results agree well with Monte Carlo
simulations and a proposed analytical model.


title:
A note on linearized stability of Schwarzschild thin-shell wormholes
  with variable equations of state

abstract:
  We discuss how the assumption of variable equation of state (EoS) allows the
elimination of the instability at equilibrium throat radius $a_0=3M$ featured
by previous Schwarzschild thin-shell wormhole models. Unobstructed stability
regions are found for three choices of variable EoS. Two of these EoS entail
linear stability at every equilibrium radius. Particularly, the thin-shell
remains stable as $a_0$ approaches the Schwarzschild radius $2M$. A
perturbative analysis of the wormhole equation of motion is carried out in the
case of variable Chaplygin EoS. The squared proper angular frequency
$\omega_0^2$ of small throat oscillations is linked with the second derivative
of the thin-shell potential. In various situations $\omega_0^2$ remains
positive and bounded in the limit $a_0\rightarrow 2M$.


title:
H\"older-continuity for the nonlinear stochastic heat equation with
  rough initial conditions

abstract:
  We study space-time regularity of the solution of the nonlinear stochastic
heat equation in one spatial dimension driven by space-time white noise, with a
rough initial condition. This initial condition is a locally finite measure
$\mu$ with, possibly, exponentially growing tails. We show how this regularity
depends, in a neighborhood of $t=0$, on the regularity of the initial
condition. On compact sets in which $t>0$, the classical H\"older-continuity
exponents $\frac{1}{4}-$ in time and $\frac{1}{2}-$ in space remain valid.
However, on compact sets that include $t=0$, the H\"older continuity of the
solution is $\left(\frac{\alpha}{2}\wedge \frac{1}{4}\right)-$ in time and
$\left(\alpha\wedge \frac{1}{2}\right)-$ in space, provided $\mu$ is absolutely
continuous with an $\alpha$-H\"older continuous density.


title:
Cryptanalysis of Sun and Cao's Remote Authentication Scheme with User
  Anonymity

abstract:
  Dynamic ID-based remote user authentication schemes ensure efficient and
anonymous mutual authentication between entities. In 2013, Khan et al. proposed
an improved dynamic ID-based authentication scheme to overcome the security
flaws of Wang et al.'s authentication scheme. Recently, Sun and Cao showed that
Khan et al. does not satisfies the claim of the user's privacy and proposed an
efficient authentication scheme with user anonymity. The Sun and Cao's scheme
achieve improvement over Khan et al.'s scheme in both privacy and performance
point of view. Unfortunately, we identify that Sun and Cao's scheme does not
resist password guessing attack. Additionally, Sun and Cao's scheme does not
achieve forward secrecy.


title:
Symbolic Synthesis of Knowledge-based Program Implementations with
  Synchronous Semantics

abstract:
  This paper deals with the automated synthesis of implementations of
knowledge-based programs with respect to two synchronous semantics (clock and
synchronous perfect recall). An approach to the synthesis problem based on the
use of symbolic representations is described. The method has been implemented
as an extension to the model checker MCK. Two applications of the implemented
synthesis system are presented: the muddy children puzzle (where performance is
compared to an explicit state method for a related problem implemented in the
model checker DEMO), and a knowledge-based program for a dynamic leader
election problem in a ring of processes.


title: Epistemic Logic for Communication Chains

abstract:
  The paper considers epistemic properties of linear communication chains. It
describes a sound and complete logical system that, in addition to the standard
axioms of S5 in a multi-modal language, contains two non-trivial axioms that
capture the linear structure of communication chains.


title: Range Separated Brueckner Coupled Cluster Doubles Theory

abstract:
  We introduce a range-separation approximation to coupled cluster doubles
(CCD) theory that successfully overcomes limitations of regular CCD when
applied to the uniform electron gas. We combine the short-range ladder channel
with the long-range ring channel in the presence of a Bruckner renormalized
one-body interaction and obtain ground-state energies with an accuracy of 0.001
a.u./electron across a wide range of density regimes. Our scheme is
particularly useful in the low-density and strongly-correlated regimes, where
regular CCD has serious drawbacks. Moreover, we cure the infamous
overcorrelation of approaches based on ring diagrams (i.e. the particle-hole
random phase approximation). Our energies are further shown to have appropriate
basis set and thermodynamic limit convergence, and overall this scheme promises
energetic properties for realistic periodic and extended systems which existing
methods do not possess.

categories: physics.chem-ph cond-mat.mtrl-sci cond-mat.other cond-mat.quant-gas


title: Koszul binomial edge ideals

abstract:
  It is shown that if the binomial edge ideal of a graph $G$ defines a Koszul
algebra, then $G$ must be chordal and claw free. A converse of this statement
is proved for a class of chordal and claw free graphs.


title: Estimating Channel Parameters from the Syndrome of a Linear Code

abstract:
  In this letter, we analyse the properties of a maximum likelihood channel
estimator based on the syndrome of a linear code. For the two examples of a
binary symmetric channel and a binary input additive white Gaussian noise
channel, we derive expressions for the bias and the mean squared error and
compare them to the Cram\'er-Rao bound. The analytical expressions show the
relationship between the estimator properties and the parameters of the linear
code, i.e., the number of check nodes and the check node degree.


title:
Transient absorption and photocurrent microscopy show hot electron
  supercollisions describe the rate-limiting relaxation step in graphene

abstract:
  Using transient absorption (TA) microscopy as a hot electron thermometer we
show disorder-assisted acoustic-phonon supercollisions (SCs) best describes the
rate-limiting relaxation step in graphene over a wide range of lattice
temperatures ($T_l=$5-300 K), Fermi energies ($E_F=\pm0.35$ eV), and optical
probe energies (~0.3 - 1.1 eV). Comparison with simultaneously collected
transient photocurrent, an independent hot electron thermometer, confirms the
rate-limiting optical and electrical response in graphene are best described by
the SC-heat dissipation rate model, $H=A(T^3_e- T^3_l)$. Our data further shows
the electron cooling rate in substrate supported graphene is twice as fast as
in suspended graphene sheets, consistent with SC-model prediction for disorder.


title:
Knowledge-Based Programs as Plans: Succinctness and the Complexity of
  Plan Existence

abstract:
  Knowledge-based programs (KBPs) are high-level protocols describing the
course of action an agent should perform as a function of its knowledge. The
use of KBPs for expressing action policies in AI planning has been surprisingly
overlooked. Given that to each KBP corresponds an equivalent plan and vice
versa, KBPs are typically more succinct than standard plans, but imply more
on-line computation time. Here we make this argument formal, and prove that
there exists an exponential succinctness gap between knowledge-based programs
and standard plans. Then we address the complexity of plan existence. Some
results trivially follow from results already known from the literature on
planning under incomplete knowledge, but many were unknown so far.


title: R.E. Axiomatization of Conditional Independence

abstract:
  The paper investigates properties of the conditional independence relation
between pieces of information. This relation is also known in the database
theory as embedded multivalued dependency. In 1980, Parker and Parsaye-Ghomi
established that the properties of this relation can not be described by a
finite system of inference rules. In 1995, Herrmann proved that the
propositional theory of this relation is undecidable. The main result of this
paper is a complete recursively enumerable axiomatization of this theory.


title:
A neutron spectrometer for studying giant resonances with (p, n)
  reactions in inverse kinematics

abstract:
  A neutron spectrometer, the European Low-Energy Neutron Spectrometer (ELENS),
has been constructed to study exotic nuclei in inverse-kinematics experiments.
The spectrometer, which consists of plastic scintillator bars, can be operated
in the neutron energy range of 100 keV to 10 MeV. The neutron energy is
determined using the time-of-flight technique, while the position of the
neutron detection is deduced from the time-difference information from
photomultipliers attached to both ends of each bar. A novel wrapping method has
been developed for the plastic scintillators. The array has a larger than 25%
detection efficiency for neutrons of approximately 500 keV in kinetic energy
and an angular resolution of less than 1 degree. Details of the design,
construction and experimental tests of the spectrometer will be presented.


title: When is an Example a Counterexample?

abstract:
  In this extended abstract, we carefully examine a purported counterexample to
a postulate of iterated belief revision. We suggest that the example is better
seen as a failure to apply the theory of belief revision in sufficient detail.
The main contribution is conceptual aiming at the literature on the
philosophical foundations of the AGM theory of belief revision [1]. Our
discussion is centered around the observation that it is often unclear whether
a specific example is a "genuine" counterexample to an abstract theory or a
misapplication of that theory to a concrete case.


title: Agreeing on Decisions: An Analysis with Counterfactuals

abstract:
  Moses & Nachum ([7]) identify conceptual flaws in Bacharach's generalization
([3]) of Aumann's seminal "agreeing to disagree" result ([1]). Essentially,
Bacharach's framework requires agents' decision functions to be defined over
events that are informationally meaningless for the agents. In this paper, we
argue that the analysis of the agreement theorem should be carried out in
information structures that can accommodate for counterfactual states. We
therefore develop a method for constructing such "counterfactual structures"
(starting from partitional structures), and prove a new agreement theorem
within such structures. Furthermore, we show that our approach also resolves
the conceptual flaws in the sense that, within our framework, decision
functions are always only defined over events that are informationally
meaningful for the agents.


title:
Model Checking an Epistemic mu-calculus with Synchronous and Perfect
  Recall Semantics

abstract:
  We identify a subproblem of the model-checking problem for the epistemic
\mu-calculus which is decidable. Formulas in the instances of this subproblem
allow free variables within the scope of epistemic modalities in a restricted
form that avoids embodying any form of common knowledge. Our subproblem
subsumes known decidable fragments of epistemic CTL/LTL, may express winning
strategies in two-player games with one player having imperfect information and
non-observable objectives, and, with a suitable encoding, decidable instances
of the model-checking problem for ATLiR.


title: Hybrid-Logical Reasoning in False-Belief Tasks

abstract:
  The main aim of the present paper is to use a proof system for hybrid modal
logic to formalize what are called falsebelief tasks in cognitive psychology,
thereby investigating the interplay between cognition and logical reasoning
about belief. We consider two different versions of the Smarties task,
involving respectively a shift of perspective to another person and to another
time. Our formalizations disclose that despite this difference, the two
versions of the Smarties task have exactly the same underlying logical
structure. We also consider the Sally-Anne task, having a somewhat more
complicated logical structure, presupposing a "principle of inertia" saying
that a belief is preserved over time, unless there is belief to the contrary.


title: Strategic Voting and the Logic of Knowledge

abstract:
  We propose a general framework for strategic voting when a voter may lack
knowledge about other votes or about other voters' knowledge about her own
vote. In this setting we define notions of manipulation and equilibrium. We
also model action changing knowledge about votes, such as a voter revealing its
preference or as a central authority performing a voting poll. Some forms of
manipulation are preserved under such updates and others not. Another form of
knowledge dynamics is the effect of a voter declaring its vote. We envisage
Stackelberg games for uncertain profiles. The purpose of this investigation is
to provide the epistemic background for the analysis and design of voting rules
that incorporate uncertainty.


title: PDL as a Multi-Agent Strategy Logic

abstract:
  Propositional Dynamic Logic or PDL was invented as a logic for reasoning
about regular programming constructs. We propose a new perspective on PDL as a
multi-agent strategic logic (MASL). This logic for strategic reasoning has
group strategies as first class citizens, and brings game logic closer to
standard modal logic. We demonstrate that MASL can express key notions of game
theory, social choice theory and voting theory in a natural way, we give a
sound and complete proof system for MASL, and we show that MASL encodes
coalition logic. Next, we extend the language to epistemic multi-agent
strategic logic (EMASL), we give examples of what it can express, we propose to
use it for posing new questions in epistemic social choice theory, and we give
a calculus for reasoning about a natural class of epistemic game models. We end
by listing avenues for future research and by tracing connections to a number
of other logics for reasoning about strategies.


title: Game Theory with Translucent Players

abstract:
  A traditional assumption in game theory is that players are opaque to one
another -- if a player changes strategies, then this change in strategies does
not affect the choice of other players' strategies. In many situations this is
an unrealistic assumption. We develop a framework for reasoning about games
where the players may be translucent to one another; in particular, a player
may believe that if she were to change strategies, then the other player would
also change strategies. Translucent players may achieve significantly more
efficient outcomes than opaque ones.
  Our main result is a characterization of strategies consistent with
appropriate analogues of common belief of rationality. Common Counterfactual
Belief of Rationality (CCBR) holds if (1) everyone is rational, (2) everyone
counterfactually believes that everyone else is rational (i.e., all players i
believe that everyone else would still be rational even if i were to switch
strategies), (3) everyone counterfactually believes that everyone else is
rational, and counterfactually believes that everyone else is rational, and so
on. CCBR characterizes the set of strategies surviving iterated removal of
minimax dominated strategies: a strategy $\sigma_i$ is minimax dominated for i
if there exists a strategy $\sigma'_i$ for i such that $\min_{\mu'_{-i}}
u_i(\sigma_i, \mu_{-i}') > \max_{\mu_{-i}} u_i(\sigma_i, \mu_{-i})$.


title:
Reasoning Under the Principle of Maximum Entropy for Modal Logics K45,
  KD45, and S5

abstract:
  We propose modal Markov logic as an extension of propositional Markov logic
to reason under the principle of maximum entropy for modal logics K45, KD45,
and S5. Analogous to propositional Markov logic, the knowledge base consists of
weighted formulas, whose weights are learned from data. However, in contrast to
Markov logic, in our framework we use the knowledge base to define a
probability distribution over non-equivalent epistemic situations (pointed
Kripke structures) rather than over atoms, and use this distribution to assign
probabilities to modal formulas. As in all probabilistic representations, the
central task in our framework is inference. Although the size of the state
space grows doubly exponentially in the number of propositions in the domain,
we provide an algorithm that scales only exponentially in the size of the
knowledge base. Finally, we briefly discuss the case of languages with an
infinite number of propositions.


title: Facebook and the Epistemic Logic of Friendship

abstract:
  This paper presents a two-dimensional modal logic for reasoning about the
changing patterns of knowledge and social relationships in networks organised
on the basis of a symmetric 'friendship' relation, providing a precise language
for exploring 'logic in the community' [11]. Agents are placed in the model,
allowing us to express such indexical facts as 'I am your friend' and 'You, my
friends, are in danger'.
  The technical framework for this work is general dynamic dynamic logic (GDDL)
[4], which provides a general method for extending modal logics with dynamic
operators for reasoning about a wide range of model-transformations, starting
with those definable in propositional dynamic logic (PDL) and extended to allow
for the more subtle operators involved in, for example, private communication,
as represented in dynamic epistemic logic (DEL) and related systems. We provide
a hands-on introduction to GDDL, introducing elements of the formalism as we
go, but leave the reader to consult [4] for technical details.
  Instead, the purpose of this paper is to investigate a number of conceptual
issues that arise when considering communication between agents in such
networks, both from one agent to another, and broadcasts to socially-defined
groups of agents, such as the group of my friends.


title:
An Epistemic Approach to Compositional Reasoning about Anonymity and
  Privacy

abstract:
  In this paper, we present an epistemic logic approach to the compositionality
of several privacy-related informationhiding/ disclosure properties. The
properties considered here are anonymity, privacy, onymity, and identity. Our
initial observation reveals that anonymity and privacy are not necessarily
sequentially compositional; this means that even though a system comprising
several sequential phases satisfies a certain unlinkability property in each
phase, the entire system does not always enjoy a desired unlinkability
property. We show that the compositionality can be guaranteed provided that the
phases of the system satisfy what we call the independence assumptions. More
specifically, we develop a series of theoretical case studies of what
assumptions are sufficient to guarantee the sequential compositionality of
various degrees of anonymity, privacy, onymity, and/or identity properties.
Similar results for parallel composition are also discussed.


title: On the critical one component regularity for 3-D Navier-Stokes system

abstract:
  Given an initial data $v_0$ with vorticity $\Om_0=\na\times v_0$ in $L^{\frac
3 2},$ (which implies that $v_0$ belongs to the Sobolev space $H^{\frac12}$),
we prove that the solution $v$ given by the classical Fujita-Kato theorem blows
up in a finite time $T^\star$ only if, for any $p$ in $ ]4,6[$ and any unit
vector $e$ in $\R^3,$ there holds $ \int_0^{T^\star}\|v(t)\cdot
e\|_{\dH^{\f12+\f2p}}^p\,dt=\infty.$ We remark that all these quantities are
scaling invariant under the scaling transformation of Navier-Stokes system.


title:
Leveraging Physical Layer Capabilites: Distributed Scheduling in
  Interference Networks with Local Views

abstract:
  In most wireless networks, nodes have only limited local information about
the state of the network, which includes connectivity and channel state
information. With limited local information about the network, each node's
knowledge is mismatched; therefore, they must make distributed decisions. In
this paper, we pose the following question - if every node has network state
information only about a small neighborhood, how and when should nodes choose
to transmit? While link scheduling answers the above question for
point-to-point physical layers which are designed for an interference-avoidance
paradigm, we look for answers in cases when interference can be embraced by
advanced PHY layer design, as suggested by results in network information
theory.
  To make progress on this challenging problem, we propose a constructive
distributed algorithm that achieves rates higher than link scheduling based on
interference avoidance, especially if each node knows more than one hop of
network state information. We compare our new aggressive algorithm to a
conservative algorithm we have presented in [1]. Both algorithms schedule
sub-networks such that each sub-network can employ advanced
interference-embracing coding schemes to achieve higher rates. Our innovation
is in the identification, selection and scheduling of sub-networks, especially
when sub-networks are larger than a single link.


title: The \mu-ordinary locus for Shimura varieties of Hodge type

abstract:
  We review the Newton stratification and Ekedahl-Oort stratification on the
special fiber of a smooth integral model for a Shimura variety of Hodge type at
a prime of good reduction. We show that the \mu-ordinary locus coincides with
the generic Ekedahl-Oort stratum, and that for any two geometric points in the
\mu-ordinary locus there is an isomorphism of the attached Dieudonne modules
with additional structure. As a consequence, we proof that the \mu-ordinary
locus is open and dense, thus generalizing the results which were already known
in the PEL-case. To prove our results we provide a method which allows to
reduce the equality of strata to a group theoretic statement.


title: Explicit resolution of three dimensional terminal singularities

abstract:
  We prove that any three dimensional terminal singularity $P \in X$ can be
resolved by a sequence of divisorial contractions with minimal discrepancies
which are weighted blowups over points.


title:
Simplified Factoring Algorithms for Validating Small-Scale Quantum
  Information Processing Technologies

abstract:
  Tomography has reached its practical limits in characterization of new
quantum devices, and there is a need for a new means of characterizing and
validating new technological advances in this field. We propose a different
verification scheme based on compiled versions of Shor's factoring algorithm
that may be extended to large circuits in the future. The general version
Shor's algorithm has been experimentally elusive due to bottlenecks associated
with the modular exponentiation operation. Experiments to date have only been
able to execute compiled versions of the latter operation. We provide some new
compiled circuits for experimentalists to use in the near future. We also
demonstrate that an additional layer of compilation can be added using
classical operations, that will reduce the number of qubits and gates needed in
a given compiled circuit.


title: Dyadic Torsion of Elliptic Curves

abstract:
  Let $k$ be a field of characteristic $0$, and let $\alpha_{1}$, $\alpha_{2}$,
and $\alpha_{3}$ be algebraically independent and transcendental over $k$. Let
$K$ be the transcendental extension of $k$ obtained by adjoining the elementary
symmetric functions of the $\alpha_{i}$'s. Let $E$ be the elliptic curve
defined over $K$ which is given by the equation $y^{2} = (x - \alpha_{1})(x -
\alpha_{2})(x - \alpha_{3})$. We define a tower of field extensions $K = K_{0}'
\subset K_{1}' \subset K_{2}' \subset ...$ by giving recursive formulas for the
generators of each $K_{n}'$ over $K_{n - 1}'$. We show that $K_{\infty}'$ is a
certain central subextension of the field $K(E[2^{\infty}]) := \bigcup_{n =
0}^{\infty} K(E[2^{n}])$, and a generator of $K(E[2^{\infty}])$ over
$K_{\infty}'(\mu_{2})$ is given. Moreover, if we assume that $k$ contains all
$2$-power roots of unity, for each $n$, we show that $K(E[2^{n}])$ contains
$K_{n}'$ and is contained in a certain quadratic extension of $K_{n + 1}'$.


title: Tomography via Correlation of Noisy Measurement Records

abstract:
  We present methods and results of shot-by-shot correlation of noisy
measurements to extract entangled state and process tomography in a
superconducting qubit architecture. We show that averaging continuous values,
rather than counting discrete thresholded values, is a valid tomographic
strategy and is in fact the better choice in the low signal-to-noise regime. We
show that the effort to measure $N$-body correlations from individual
measurements scales exponentially with $N$, but with sufficient signal-to-noise
the approach remains viable for few-body correlations. We provide a new
protocol to optimally account for the transient behavior of pulsed
measurements. Despite single-shot measurement fidelity that is less than
perfect, we demonstrate appropriate processing to extract and verify entangled
states and processes.


title:
Dynamic Length Scales in Glass-Forming Liquids: A Inhomogeneous
  Molecular Dynamics Simulation Approach

abstract:
  In this work we numerically investigate a new method for the characterization
of growing length scales associated with spatially heterogeneous dynamics of
glass-forming liquids. This approach, motivated by the formulation of the
inhomogeneous mode-coupling theory (IMCT) [Biroli G. et al. Phys. Rev. Lett.
2006 97, 195701], utilizes inhomogeneous molecular dynamics simulations in
which the system is perturbed by a spatially modulated external potential. We
show that the response of the two-point correlation function to the external
field allows one to probe dynamic correlations. We examine the critical
properties shown by this function, in particular the associated dynamic
correlation length, that is found to be comparable to the one extracted from
standardly-employed four-point correlation functions. Our numerical results are
in qualitative agreement with IMCT predictions but suggest that one has to take
into account fluctuations not included in this mean-field approach in order to
reach quantitative agreement. Advantages of our approach over the more
conventional one based on four-point correlation functions are discussed.


title:
Zeeman-tuned rotational level-crossing spectroscopy in a diatomic free
  radical

abstract:
  Rotational levels of molecular free radicals can be tuned to degeneracy using
laboratory-scale magnetic fields. Because of their intrinsically narrow width,
these level crossings of opposite-parity states have been proposed for use in
the study of parity-violating interactions and other applications. We
experimentally study a typical manifestation of this system using $^{138}$BaF.
Using a Stark-mixing method for detection, we demonstrate level-crossing
signals with spectral width as small as 6 kHz. We use our data to verify the
predicted lineshapes, transition dipole moments, and Stark shifts, and to
precisely determine molecular magnetic g-factors. Our results constitute an
initial proof-of-concept for use of this system to study nuclear spin-dependent
parity violating effects.


title:
Optical Conductivity Measurement of a Dimer-Mott to Charge-Order Phase
  Transition in a Two-Dimensional Quarter-Filled Organic Salt Compound

abstract:
  We report a novel insulator-insulator transition arising from the internal
charge degrees of freedom in the two-dimensional quarter-filled organic salt
beta-(meso-DMBEDT-TTF)2PF6. The optical conductivity spectra above Tc = 70 K
display a prominent feature of the dimer-Mott insulator, characterized by a
substantial growth of a dimer peak near 0.6 eV with decreasing temperature. The
dimer-peak growth is rapidly quenched as soon as a peak of the charge order
shows up below Tc, indicating a competition between the two insulating phases.
Our infrared imaging spectroscopy has further revealed a spatially competitive
electronic phases far below Tc, suggesting a nature of quantum phase transition
driven by material-parameter variations.


title:
Finite resolution fluctuation measurements of a trapped Bose-Einstein
  condensate

abstract:
  We consider the fluctuations in atom number that occur within finite-sized
measurement cells in a trapped Bose-Einstein condensate (BEC). This
approximates the fluctuation measurements made in current experiments with
finite resolution in situ imaging. A numerical scheme is developed to calculate
these fluctuations using the quasiparticle modes of a cylindrically symmetric
three-dimensionally trapped condensate with either contact or dipole-dipole
interactions (DDIs). We use this scheme to study the properties of a pancake
shaped condensate using cylindrical cells. The extension of the theory to
washer shaped cells with azimuthal weighting is made and used to discriminate
between the low energy roton modes in a dipolar condensate according to their
pro- jection of angular momentum. Our results are based on the Bogoliubov
approach valid for zero and small finite temperatures.


title:
The Origin of Half-Metallicity in Conjugated Electron System -- a Study
  on Transition Metal Doped Graphyne

abstract:
  We studied the mechanism of half-metallicity (HM) formation in transition
metal doped (TM) conjugated carbon based structures by first-principles
electronic structure simulations. It is found that the HM is a rather complex
phenomenon, determined by the ligand field splitting of d-orbitals of the
transition metal (TM) atoms, the exchange splitting and the number of valence
electrons. Since most of the conjugated carbon based structures possess ligands
with intermediate strength, the ordering of the d-orbital splitting is similar
in all structures, and the HM properties evolve according to the number of
valence electrons. Based on this insight we predict that Cr-, Fe-, Co-doped
graphyne will show HM, while Mn- and Ni-doped graphyne will not. By tuning the
number of valence electron, we are thus able to control the emergence of HM and
control the energy gaps evolving in majority or minority spin channels.


title:
Measurement of Optical Attenuation in Acrylic Light Guides for a Dark
  Matter Detector

abstract:
  Acrylic is a common material used in dark matter and neutrino detectors for
light guides, transparent vessels, and neutron shielding, creating an
intermediate medium between the target volume and photodetectors. Acrylic has
low absorption within the visible spectrum and has a high capture cross section
for neutrons. The natural radioactivity in photodetectors is a major source of
background neutrons for low background detectors making the use of acrylic
attractive for shielding and background reduction. To test the optical
properties of acrylic we measured the transmittance and attenuation length of
fourteen samples of acrylic from four different manufacturers. Samples were
evaluated at five different wavelengths between 375 nm and 632 nm. We found
that all samples had excellent transmittance at wavelengths greater than 550
nm. Transmittance was found to decrease below 550 nm. As expected, UV-absorbing
samples showed a sharp decrease in transmittance below 425 nm compared to
UV-transmitting samples. We report attenuation lengths for the three shortest
wavelengths for comparison and discuss how the acrylic was evaluated for use in
the MiniCLEAN single-phase dark matter detector.


title: Killing frames and S-curvature of homogeneous Finsler spaces

abstract:
  In this paper, we first deduce a formula of S-curvature of homogeneous
Finsler spaces in terms of Killing vector fields. Then we prove that a
homogeneous Finsler space has isotropic S-curvature if and only if it has
vanishing S-curvature. In the special case that the homogeneous Finsler space
is a Randers space, we give an explicit formula which coincides with the
previous formula obtained by the second author using other methods.


title:
Finite-field calculation of the polarizabilities and
  hyperpolarizabilities of Al$^{+}$

abstract:
  In this study, accurate static dipole polarizability and hyperpolarizability
are calculated for Al$^+$ ground state 3s$^{2}$ $^{1}$S$_{0}$ and excited state
$3s3p$ $^{3}$P$_{J}$ with $J$=0, 1, 2. The finite-field computations use
energies obtained with the relativistic configuration interaction approach and
the relativistic coupled-cluster approach. Excellent agreement with previously
recommended values is found for the dipole polarizability of Al$^{+}$ ground
state 3s$^{2}$ $^{1}$S$_{0}$ and excited state $3s3p$ $^{3}$P$_{0}$ as well as
the hyperpolarizability of the ground state 3s$^{2}$ $^{1}$S$_{0}$. The
recommended values of the dipole polarizability of the Al$^{+}$ $3s3p$
$^{3}$P$_{1}$ and $^{3}$P$_{2}$ and the hyperpolarizability of Al$^{+}$ $3s3p$
$^{3}$P$_{0}$, $^{3}$P$_{1}$, and $^{3}$P$_{2}$ are also given. The impacts of
the relativity and spin-orbit coupling are elucidated by analyzing the angular
momentum dependence of the dipole polarizability and the hyperpolarizability
and comparing the fully and scalar relativistic calculated data. It is shown
that the impact of the relativity and spin-orbit coupling are small for the
dipole polarizability but become significant for the hyperpolarizability.
Finally, the black-body radiation shifts contributed by the dipole
polarizability and hyperpolarizability respectively are evaluated for
transitions of Al$^{+}$ 3s$^{2}$ $^{1}$S$_{0}$ to $3s3p$ $^{3}$P$_{J}$ with
$J$=0, 1, 2.


title:
Effects of ozone post deposition treatment on interfacial and electrical
  characteristics of atomic-layer-deposited Al2O3 and HfO2 films on GaSb
  substrates

abstract:
  Atomic-layer-deposited Al2O3 and HfO2 films on GaSb substrates were treated
by in-situ ozone post deposition treatment (PDT). The effects of ozone PDT on
the interfacial and electrical properties of Al2O3 and HfO2 gate dielectric
films on GaSb substrates were investigated carefully. It is found that the
dielectric quality and the interfacial properties of the Al2O3 and HfO2 films
are improved by ozone PDT. After in-situ ozone PDT for 5 min, the Al2O3 and
HfO2 films on GaSb substrates exhibit improved electrical and interfacial
properties, such as reduced frequency dispersion, gate leakage current, border
traps and interface traps. Interface trap density is reduced by ~24% for the
Al2O3/GaSb stacks and ~27% for the HfO2/GaSb stacks. In-situ ozone PDT is
proved to be a promising technique in improving the quality of high-k gate
stacks on GaSb substrates.


title:
Activity Related Variations of High-Degree p-Mode Amplitude, Width and
  Energy in Solar Active Regions

abstract:
  We study the properties of high degree p-mode oscillations in flaring and
dormant ARs and compare them with those in corresponding quiet regions (QRs) to
find the association of mode parameters with magnetic and flare related
activities. Our analysis of several flaring and dormant ARs, showed strong
association of mode amplitude, width and energy with magnetic and flare
activities although their changes are combined effects of foreshortening,
filling factor, magnetic activity, flare activity, and measurement
uncertainties. We find that the largest decrease in mode amplitude and
background power of an AR are caused by the angular distance of the AR from the
solar disc centre. After correcting the mode parameters for foreshortening and
filling factor, we find that the mode amplitude of flaring and dormant ARs are
smaller than in corresponding QRs, and decreases with increasing MAI suggesting
a larger mode power suppression in ARs with stronger magnetic fields. The mode
widths in ARs are larger than in corresponding QRs and increase with MAI,
indicating shorter lifetimes of modes in ARs than in QRs. The largest decrease
(increase) in mode amplitude (mode width) of dormant ARs is found in the five
minute frequency band. The average mode energy of both the flaring and dormant
ARs are smaller than in their corresponding QRs, decreasing with increasing
MAI. But the average mode energy decrease rate in flaring ARs are smaller than
in dormant ARs. Also, the increase in mode width rate in dormant (flaring) ARs
is followed by decrease (increase) in amplitude variation rate. Furthermore,
inclusion of mode corrections for MAI shows that mode amplitude and mode energy
of flaring ARs increase with FI while mode width shows an opposite trend. The
increase (decrease) in mode amplitude (width) is larger in the five minute and
higher frequency band. Increase in width variation rate is ...


title: Neutrino clustering around spherical dark matter halos

abstract:
  Cold dark matter halos form within a smoothly distributed background of relic
neutrinos -- at least some of which are massive and non-relativistic at late
times. We calculate the accumulation of massive neutrinos around spherically
collapsing cold dark matter halos in a cosmological background. We identify the
physical extent of the "neutrino halo" in the spherical collapse model, which
is large in comparison with the virial radius of the dark matter, and
conditions under which neutrinos reaching the cold dark matter halo will remain
bound to the halo at late times. We calculate the total neutrino mass and bound
neutrino mass associated with isolated spherical halos for several neutrino
mass hierarchies and provide fitting formulae for these quantities in terms of
the cold dark matter halo mass and the masses of the individual neutrino
species.


title:
Temporal homogenization of linear ODEs, with applications to parametric
  super-resonance and energy harvest

abstract:
  We consider the temporal homogenization of linear ODEs of the form
$\dot{x}=Ax+\epsilon P(t)x+f(t)$, where $P(t)$ is periodic and $\epsilon$ is
small. Using a 2-scale expansion approach, we obtain the long-time
approximation $x(t)\approx \exp(At) \left( \Omega(t)+\int_0^t \exp(-A \tau)
f(\tau) \, d\tau \right)$, where $\Omega$ solves the cell problem
$\dot{\Omega}=\epsilon B \Omega + \epsilon F(t)$ with an effective matrix $B$
and an explicitly-known $F(t)$. We provide necessary and sufficient condition
for the accuracy of the approximation (over a $\mathcal{O}(\epsilon^{-1})$
time-scale), and show how $B$ can be computed (at a cost independent of
$\epsilon$). As a direct application, we investigate the possibility of using
RLC circuits to harvest the energy contained in small scale oscillations of
ambient electromagnetic fields (such as Schumann resonances). Although a RLC
circuit parametrically coupled to the field may achieve such energy extraction
via parametric resonance, its resistance $R$ needs to be smaller than a
threshold $\kappa$ proportional to the fluctuations of the field, thereby
limiting practical applications. We show that if $n$ RLC circuits are
appropriately coupled via mutual capacitances or inductances, then energy
extraction can be achieved when the resistance of each circuit is smaller than
$n\kappa$. Hence, if the resistance of each circuit has a non-zero fixed value,
energy extraction can be made possible through the coupling of a sufficiently
large number $n$ of circuits ($n\approx 1000$ for the first mode of Schumann
resonances and contemporary values of capacitances, inductances and
resistances). The theory is also applied to the control of the oscillation
amplitude of a (damped) oscillator.


title:
Lattice NRQCD study of in-medium bottomonium states using $N_f = 2+1,
  48^3 \times 12$ HotQCD configurations

abstract:
  The behavior of bottomonium state correlators at non-zero temperature, $140.4
(\beta = 6.664) \le T \le 221 (\beta = 7.280)$ (MeV), where the transition
temperature is $154(9)$ (MeV), is studied, using lattice NRQCD on $48^3 \times
12$ HotQCD HiSQ action configurations with light dynamical $N_f = 2 + 1$
($m_{u,s}/m_s = 0.05$) staggered quarks. In order to understand finite
temperature effects on quarkonium states, zero temperature behavior of
bottomonium correlators is compared based on $32^4$ ($\beta = 6.664, 6.800$ and
$6.950$) and $48^3 \times 64$ ($\beta = 7.280)$ lattices. We find that
temperature effects on S-wave bottomonium states are small but P-wave
bottomonium states show a noticeable temperature dependence above the
transition temperature.


title: Chromospheric Doppler Velocity Oscillations in a Sunspot

abstract:
  We analyse the chromospheric Doppler velocity oscillations in a sunspot using
the high resolution spectral observations obtained from the Fast Imaging Solar
Spectrograph(FISS) of the New Solar Telescope at the Big Bear Solar
Observatory. The Doppler velocity maps are constructed from the bisectors of
the spectral observations. The time series analysis of Doppler velocity maps
show enhanced power in the sunspot umbra at higher frequencies and in the
penumbra at lower frequencies. We find that the peak power frequency decreases
gradually from the umbra to outward.


title: Boundary Value Problems for a Family of Domains in the Sierpinski Gasket

abstract:
  For a family of domains in the Sierpinski gasket, we study harmonic functions
of finite energy, characterizing them in terms of their boundary values, and
study their normal derivatives on the boundary. We characterize those domains
for which there is an extension operator for functions of finite energy. We
give an explicit construction of the Green's function for these domains.


title: Seismology of Flaring and Dormant Active Regions

abstract:
  We study photospheric and sub-photospheric properties of active and quiet
regions observed during 11-17 February 2011 including the first X-class flare
X2.2 of the solar cycle 24 which occurred in the active region NOAA 11158 on 15
February 2011. The p-mode parameters and sub-photospheric flows are computed
from the ring-diagrams and inversions. We found larger frequency shifts in
active regions than quiet regions. The active region NOAA 11158 shows stronger
twisted sub-photospheric flows than dormant active regions. The kinetic
helicity density of sub-photospheric flows of the active region NOAA 11158
shows different structure on the flare day than the pre- and post flare days.


title:
Frequency Modulation Spectroscopy at High Modulation Depth in an Indium
  Atomic Beam

abstract:
  We present a detailed analysis of an application of frequency modulation (FM)
spectroscopy in the high modulation depth limit. We have recently completed and
reported a measurement of the Stark shift in the indium $5p_{1/2}\rightarrow
6s_{1/2}$ 410 nm transition using this spectroscopy method [Ranjit, et al.
Phys. Rev. A 87, 032506 (2013)]. FM spectroscopy proved essential to resolve
spectroscopic features in an atomic beam where the optical depth was $\sim
10^{-3}$. A dual-modulation scheme is described which ensures truly
background-free FM signals even in the low-density limit. Lock-in detection of
the FM signal was accomplished using both the fundamental (1f) and
second-harmonic (2f) modulation frequencies. A derivation of both the 1f and 2f
signal line shapes in the high-modulation-depth limit is presented. These line
shapes form the basis for quantitative fits to a wide variety of experimental
FM spectra.


title: Ramsey precompact expansions of homogeneous directed graphs

abstract:
  In 2005, Kechris, Pestov and Todorcevic provided a powerful tool to compute
an invariant of topological groups known as the universal minimal flow,
immediately leading to an explicit representation of this invariant in many
concrete cases. More recently, the framework was generalized allowing for
further applications, and the purpose of this paper is to apply these new
methods in the context of homogeneous directed graphs.
  In this paper, we show that the age of any homogeneous directed graph allows
a Ramsey precompact expansion. Moreover, we verify the relative expansion
properties and consequently describe the respective universal minimal flows.


title:
Representation of integers by a family of cubic forms in seven variables
  II

abstract:
  In an earlier paper [4], we derived asymptotic formulas for the number of
representations of zero and of large positive integers by the cubic forms in
seven variables which can be written as $L_1(x_1,x_2,x_3) Q_1(x_1,x_2,x_3)+
L_2(x_4,x_5,x_6) Q_2(x_4,x_5,x_6) + a_7 x_7^3$ where $L_1$ and $L_2$ are linear
forms, $Q_1$ and $Q_2$ are quadratic forms and $a_7$ is a non-zero integer and
for which certain quantities related to $L_1Q_1$ and $L_2Q_2$ were non-zero. In
this paper, we consider the case when one or both of these quantities is zero
but $L_1Q_1$ and $L_2Q_2$ are still nondegenerate cubic forms in three
variables.


title:
Measurement of $H(z)$ and $D_A(z)$ from the two-dimensional power
  spectrum of Sloan Digital Sky Survey luminous red galaxies

abstract:
  We present a method to measure the Hubble parameter $H(z)$ and the angular
diameter distance $D_A(z)$ simultaneously from the two-dimensional matter power
spectrum from galaxy surveys with broad sky coverage. We validate this method
by applying it to the LasDamas mock galaxy catalogs. Then we apply this method
to Sloan Digital Sky Survey (SDSS) Data Release 7 and obtain measurements of
$\Omega_mh^2=0.1268 \pm 0.0085$, $H(z=0.35)=81.3\pm 3.8$km/s/Mpc, $D_A(z=0.35)
= 1037\pm44$Mpc, without assuming a dark energy model or a flat universe. We
also find that the derived parameters $H(0.35)r_s(z_d)/c=0.0431 \pm 0.0018$ and
$D_A(0.35)/r_s(z_d)=6.48 \pm 0.25$. These are in excellent agreement with
similar measurements from the two-dimensional correlation function of the same
data.


title: Superluminal Vector in Ghost-free Massive Gravity

abstract:
  We present a classical analysis on the issue of vector superluminality in the
decoupling limit ghost-free massive gravity with a Minkowski reference metric.
We show explicitly in the Lorenz gauge that the theory is free of superluminal
vector excitations around a nontrivial solution at the cubic order in the
fields. In the same gauge, we demonstrate that superluminal vector modes arise
at the quartic order and compute some superluminal propagating solutions. We
then generalize our findings to all orders in a gauge-independent way. We check
the physical consistency of the vector superluminalities, arguing that they are
not physically detectable in the perturbation theory but could be trusted
classically in the strong coupling region. Nevertheless, these
superluminalities involve only low frequency group and phase velocities and are
unable to determine the acausality of the theory.


title:
Minkowski structure for purity and entanglement of Gaussian bipartite
  states

abstract:
  The relation between the symplectic and Lorentz groups is explored to
investigate entanglement features in a two-mode bipartite Gaussian state. We
verify that the correlation matrix of arbitrary Gaussian states can be
associated to a hyperbolic space with a Minkowski metric, which is divided in
two regions - separablelike and entangledlike, in equivalence to timelike and
spacelike in special relativity. This correspondence naturally allows the
definition of two insightful invariant squared distances measures - one related
to the purity and another related to amount of entanglement. The second
distance allows us to define a measure for entanglement in terms of the
invariant interval between the given state and its closest separable state,
given in a natural manner without the requirement of a minimization procedure.


title:
A Liouville theorem for the planer Navier-Stokes equations with the
  no-slip boundary condition and its application to a geometric regularity
  criterion

abstract:
  We establish a Liouville type result for a backward global solution to the
Navier-Stokes equations in the half plane with the no-slip boundary condition.
No assumptions on spatial decay for the vorticity nor the velocity field are
imposed. We study the vorticity equations instead of the original Navier-Stokes
equations. As an application, we extend the geometric regularity criterion for
the Navier-Stokes equations in the three-dimensional half space under the
no-slip boundary condition.


title:
Radiative emission of neutrino pair from nucleus and inner core
  electrons in heavy atoms

abstract:
  Radiative emission of neutrino pair (RENP) from atomic states is a new tool
to experimentally investigate undetermined neutrino parameters such as the
smallest neutrino mass, the nature of neutrino masses (Majorana vs Dirac), and
their CP properties. We study effects of neutrino pair emission either from
nucleus or from inner core electrons in which the zero-th component of quark or
electron vector current gives rise to large coupling. Both the overall rate and
the spectral shape of photon energy are given for a few cases of interesting
target atoms. Calculated rates exceed those of previously considered target
atoms by many orders of magnitudes.


title:
On the F-rationality and cohomological properties of matrix Schubert
  varieties

abstract:
  We characterize complete intersection matrix Schubert varieties, generalizing
the classical result on one-sided ladder determinantal varieties. We also give
a new proof of the F-rationality of matrix Schubert varieties. Although it is
known that such varieties are F-regular (hence F-rational) by the global
F-regularity of Schubert varieties, our proof is of independent interest since
it does not require the Bott-Samelson resolution. As a consequence, this
provides an alternative proof of the classical fact that Schubert varieties in
flag varieties are normal and have rational singularities.


title: A possible Harappan Astronomical Observatory at Dholavira

abstract:
  Astronomy arises very early in a civilization and evolves as the civilization
advances. It is therefore reasonable to assume that a vibrant knowledge of
astronomy would have been a feature of a civilization the size of the Harappan
Civilization. We suggest that structures dedicated to astronomy existed in
every major Harappan city. One such city was Dholavira, an important trading
port that was located on an island in what is now the Rann of Kutch during the
peak of the Harappan Civilization. We have analyzed an unusual structure at
Dholavira that includes two circular rooms. Upon assuming strategically-placed
holes in their ceilings we examine the internal movement of sunlight within
these rooms and suggest that the larger structure of which they formed a part
could have functioned as an astronomical observatory.


title:
A time continuation based fast approximate algorithm for compressed
  sensing related optimization

abstract:
  Recently, significant connections between compressed sensing problems and
optimization of a particular class of functions relating to solutions of
Hamilton-Jacobi equation was discovered. In this paper we introduce a fast
approximate algorithm to optimize this particular class of functions and
subsequently find the solution to the compressed sensing problem. Although we
emphasize that the methodology of our algorithm finds an approximate solution,
numerical experiments show that our algorithm perfectly recovers the solution
when the solution is relatively sparse with respect to the number of
measurements. In these scenarios, the recovery is extremely fast compare to
other methods available. Numerical experiments also demonstrate that the
algorithm exhibits a sharp phase transition in success rate of recovery of the
solution to compressed sensing problems as sparsity of solution varies. The
algorithm proposed here is parameter free (except a tolerance parameter due to
numerical machine precision), and very easy to implement.


title:
Minority-spin $t_{2g}$ states and the degree of spin polarization in
  ferromagnetic metallic La$_{2-2x}$Sr$_{1+2x}$Mn$_2$O$_7$ ($x=0.38$)

abstract:
  Using angle-resolved photoemission spectroscopy (ARPES), we investigate the
electronic band structure and Fermi surface of ferromagnetic
La$_{2-2x}$Sr$_{1+2x}$Mn$_2$O$_7$ ($x=0.38$). Besides the expected two hole
pockets and one electron pocket of majority-spin $e_g$ electrons, we show an
extra electron pocket around the $\Gamma$ point. A comparison with
first-principles spin-polarized band-structure calculations shows that the
extra electron pocket arises from $t_{2g}$ electrons of minority-spin
character, indicating this compound is not a complete half-metallic
ferromagnet, with similar expectations for lightly-doped cubic manganites.
However, our data suggest that a complete half-metallic state is likely to be
reached as long as the bandwidth is mildly reduced. Moreover, the band-resolved
capability of ARPES enables us to investigate the band structure effects on
spin polarization for different experimental conditions.


title: Mixing in high-dimensional expanders

abstract:
  We prove a generalization of the Expander Mixing Lemma for arbitrary (finite)
simplicial complexes. The original lemma states that concentration of the
Laplace spectrum of a graph implies combinatorial expansion (which is also
referred to as mixing, or quasi-randomness). Recently, an analogue of this
Lemma was proved for simplicial complexes of arbitrary dimension, provided that
the skeleton of the complex is complete. More precisely, it was shown that a
concentrated spectrum of the simplicial Hodge Laplacian implies a similar type
of expansion as in graphs. In this paper we remove the assumption of a complete
skeleton, showing that concentration of the Laplace spectra in all dimensions
implies combinatorial expansion in any complex. As applications we show that
spectral concentration implies Gromov's geometric overlap property, and can be
used to bound the chromatic number of a complex.


title:
Strange and multi-strange particle production in Pb-Pb collisions at
  $\sqrt{s_{NN}}$ = 2.76 TeV with ALICE

abstract:
  We present ALICE results on strange and multi-strange hadron production as a
function of centrality in Pb-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 2.76 TeV
at the LHC. Their transverse momentum spectra, yields and particle ratios are
compared to the corresponding measurements in pp collisions to address
strangeness enhancement and high $p_{\rm T}$ particle suppression. The results
are also compared to measurements at RHIC and SPS energies.


title:
Modular Transformations and Verlinde Formulae for Logarithmic
  $(p_+,p_-)$-Models

abstract:
  The $(p_+,p_-)$ singlet algebra is a vertex operator algebra that is strongly
generated by a Virasoro field of central charge $1-6(p_+-p_-)^2/p_+p_-$ and a
single Virasoro primary field of conformal weight $(2p_+-1)(2p_--1)$. Here, the
modular properties of the characters of the uncountably many simple modules of
each singlet algebra are investigated and the results used as the input to a
continuous analogue of the Verlinde formula to obtain the "fusion rules" of the
singlet modules. The effect of the failure of fusion to be exact in general is
studied at the level of Verlinde products and the rules derived are lifted to
the $(p_+,p_-)$ triplet algebras by regarding these algebras as simple current
extensions of their singlet cousins. The result is a relatively effortless
derivation of the triplet "fusion rules" that agrees with those previously
proposed in the literature.


title:
Spin-Spin Correlation Enhanced by Impurities in a Frustrated Two-leg
  Spin Ladder

abstract:
  We theoretically study a spin-spin correlation enhanced by non-magnetic
impurities in a frustrated two-leg spin ladder. The frustration is introduced
by the next-nearest-neighbor antiferromagnetic interaction in the leg direction
in the antiferromagnetic two-leg spin ladder. The spin-spin correlation
function around impurity site is calculated by the density-matrix
renormalization-group method. We find that the spin-spin correlation is
enhanced around impurity site with the wavenumber reflecting the frustration.
As increasing the frustration, the wavenumber is shifted from commensurate to
incommensurate. We discuss several experimental results on BiCu2PO6 in the
light of our theory.


title: Barrier Certificates Revisited

abstract:
  A barrier certificate can separate the state space of a con- sidered hybrid
system (HS) into safe and unsafe parts ac- cording to the safety property to be
verified. Therefore this notion has been widely used in the verification of
HSs. A stronger condition on barrier certificates means that less expressive
barrier certificates can be synthesized. On the other hand, synthesizing more
expressive barrier certificates often means high complexity. In [9], Kong et al
consid- ered how to relax the condition of barrier certificates while still
keeping their convexity so that one can synthesize more expressive barrier
certificates efficiently using semi-definite programming (SDP). In this paper,
we first discuss how to relax the condition of barrier certificates in a
general way, while still keeping their convexity. Particularly, one can then
utilize different weaker conditions flexibly to synthesize dif- ferent kinds of
barrier certificates with more expressiveness efficiently using SDP. These
barriers give more opportuni- ties to verify the considered system. We also
show how to combine two functions together to form a combined barrier
certificate in order to prove a safety property under consid- eration, whereas
neither of them can be used as a barrier certificate separately, even according
to any relaxed condi- tion. Another contribution of this paper is that we
discuss how to discover certificates from the general relaxed condi- tion by
SDP. In particular, we focus on how to avoid the unsoundness because of numeric
error caused by SDP with symbolic checking


title:
Algebraic combinatorial geometry: the polynomial method in arithmetic
  combinatorics, incidence combinatorics, and number theory

abstract:
  Arithmetic combinatorics is often concerned with the problem of bounding the
behaviour of arbitrary finite sets in a group or ring with respect to
arithmetic operations such as addition or multiplication. Similarly,
combinatorial geometry is often concerned with the problem of bounding the
behaviour of arbitrary finite collections of geometric objects such as points,
lines, or circles with respect to geometric operations such as incidence or
distance. Given the presence of arbitrary finite sets in these problems, the
methods used to attack these problems have primarily been combinatorial in
nature. In recent years, however, many outstanding problems in these questions
have been solved by algebraic means (and more specifically, using tools from
algebraic geometry and/or algebraic topology), giving rise to an emerging set
of techniques which is now known as the polynomial method.
  While various instances of the polynomial method have been known for decades
(e.g. Stepanov's method, the combinatorial nullstellensatz, or Baker's
theorem), the general theory of this method is still in the process of
maturing; in particular, the limitations of the polynomial method are not well
understood, and there is still considerable scope to apply deeper results from
algebraic geometry or algebraic topology to strengthen the method further. In
this survey we present several of the known applications of these methods,
focusing on the simplest cases to illustrate the techniques. We will assume as
little prior knowledge of algebraic geometry as possible.


title:
Temperature Dependence of Alkali-Metal Rattling Dynamics in the
  {\beta}-Pyrochlores, AOs2O6 (A = K, Rb, Cs), from MD Simulation

abstract:
  We investigate the temperature response of the alkali-metal rattling modes in
{\beta}-pyrochlores, AOs2O6 (A = K, Rb, Cs), from the results of ab initio
molecular dynamics (MD) simulations performed at 20 K, 100 K, and 300 K. Our
results show that the temperature response of the T1u mode is clearly different
from that of the T2g mode for all three pyrochlores. In this regard, two
features are of particular note for both K and Rb; (1) the T1u mode exhibits a
distinctly stronger softening response with decreasing temperature compared to
the T2g mode, and (2) the T1u mode becomes stronger and sharper with decreasing
temperature. These two findings suggest that the T1u mode is significantly more
anharmonic and sensitive to the cage dynamics than the T2g mode. Examination of
the local potentials around the alkali-metal atoms reveals that K has the
flattest and most anharmonic potential at all temperatures while Cs exhibits
the narrowest potential. The temperature dependence of the local potentials
reveals that, for K, the potential at a higher temperature is not a simple
extrapolation to higher energy of that at a lower temperature. Instead, we find
significant reconstruction of the potential at different temperatures. Finally,
we explore the temperature response of the coupling between the alkali metals
and find a complex temperature dependence which suggests that the origin of the
coupling may be more complex than a pure Coulomb interaction. We also find an
unexpected increase in the static disorder of the system at low temperatures
for the K and Rb pyrochlores.