title: Toward a Science of Autonomy for Physical Systems: Paths

abstract:
  An Autonomous Physical System (APS) will be expected to reliably and
independently evaluate, execute, and achieve goals while respecting surrounding
rules, laws, or conventions. In doing so, an APS must rely on a broad spectrum
of dynamic, complex, and often imprecise information about its surroundings,
the task it is to perform, and its own sensors and actuators. For example,
cleaning in a home or commercial setting requires the ability to perceive,
grasp, and manipulate many physical objects, the ability to reliably perform a
variety of subtasks such as washing, folding, and stacking, and knowledge about
local conventions such as how objects are classified and where they should be
stored. The information required for reliable autonomous operation may come
from external sources and from the robot's own sensor observations or in the
form of direct instruction by a trainer. Similar considerations apply across
many domains - construction, manufacturing, in-home assistance, and healthcare.
For example, surgeons spend many years learning about physiology and anatomy
before they touch a patient. They then perform roughly 1000 surgeries under the
tutelage of an expert surgeon, and they practice basic maneuvers such as suture
tying thousands of times outside the operating room. All of these elements come
together to achieve expertise at this task. Endowing a system with robust
autonomy by traditional programming methods has thus far had limited success.
Several promising new paths to acquiring and processing such data are emerging.
This white paper outlines three promising research directions for enabling an
APS to learn the physical and information skills necessary to perform tasks
with independence and flexibility: Deep Reinforcement Learning, Human-Robot
Interaction, and Cloud Robotics.


title: Generalized Fano and non-Fano networks

abstract:
  It is known that the Fano network has a vector linear solution if and only if
the characteristic of the finite field is $2$; and the non-Fano network has a
vector linear solution if and only if the characteristic of the finite field is
not $2$. Using these properties of Fano and non-Fano networks it has been shown
that linear network coding is insufficient. In this paper we generalize the
properties of Fano and non-Fano networks. Specifically, by adding more nodes
and edges to the Fano network, we construct a network which has a vector linear
solution for any vector dimension if and only if the characteristic of the
finite field belongs to an arbitrary given set of primes
$\{p_1,p_2,\ldots,p_l\}$. Similarly, by adding more nodes and edges to the
non-Fano network, we construct a network which has a vector linear solution for
any vector dimension if and only if the characteristic of the finite field does
not belong to an arbitrary given set of primes $\{p_1,p_2,\ldots,p_l\}$.


title:
The problem of kinematic mass corrections for unpolarized semi-inclusive
  deep inelastic scattering

abstract:
  Miraculously, target mass corrections for inclusive deep inelastic scattering
can be calculated exactly. On the contrary, there does not exist a consistent
derivation of kinematic hadron mass corrections for semi-inclusive deep
inelastic scattering (SIDIS). Recently this has become of topical interest,
since there is a significant difference between the measured HERMES and COMPASS
pion and kaon multiplicities, which cannot be explained as a consequence of
evolution in $Q^2$, and it has been suggested that the difference can be
understood if kinematic hadron mass corrections are taken into account. We
explain why this argument is incorrect.


title: Curves of equiharmonic solutions, and problems at resonance

abstract:
  We consider the semilinear Dirichlet problem \[ \Delta u+kg(u)=\mu _1 \varphi
_1+\cdots +\mu _n \varphi _n+e(x) \;\; \mbox{for $x \in \Omega$}, \;\; u=0 \;\;
\mbox{on $\partial \Omega$}, \] where $\varphi _k$ is the $k$-th eigenfunction
of the Laplacian on $\Omega$ and $e(x) \perp \varphi _k$, $k=1, \ldots, n$.
Write the solution in the form $u(x)= \Sigma _{i=1}^n \xi _i \varphi _i+U(x)$,
with $ U \perp \varphi _k$, $k=1, \ldots, n$. Starting with $k=0$, when the
problem is linear, we continue the solution in $k$ by keeping $\xi =(\xi _1,
\ldots,\xi _n)$ fixed, but allowing for $\mu =(\mu _1, \ldots,\mu _n)$ to vary.
Studying the map $\xi \rightarrow \mu$ provides us with the existence and
multiplicity results for the above problem. We apply our results to problems at
resonance, at both the principal and higher eigenvalues. Our approach is
suitable for numerical calculations, which we implement, illustrating our
results.


title: Toward a Science of Autonomy for Physical Systems: Service

abstract:
  A recent study by the Robotic Industries Association has highlighted how
service robots are increasingly broadening our horizons beyond the factory
floor. From robotic vacuums, bomb retrievers, exoskeletons and drones, to
robots used in surgery, space exploration, agriculture, home assistance and
construction, service robots are building a formidable resume. In just the last
few years we have seen service robots deliver room service meals, assist
shoppers in finding items in a large home improvement store, checking in
customers and storing their luggage at hotels, and pour drinks on cruise ships.
Personal robots are here to educate, assist and entertain at home. These
domestic robots can perform daily chores, assist people with disabilities and
serve as companions or pets for entertainment. By all accounts, the growth
potential for service robotics is quite large.


title:
Progress of the Felsenkeller shallow-underground accelerator for nuclear
  astrophysics

abstract:
  Low-background experiments with stable ion beams are an important tool for
putting the model of stellar hydrogen, helium, and carbon burning on a solid
experimental foundation. The pioneering work in this regard has been done by
the LUNA collaboration at Gran Sasso, using a 0.4 MV accelerator. In the
present contribution, the status of the project for a higher-energy underground
accelerator is reviewed. Two tunnels of the Felsenkeller underground site in
Dresden, Germany, are currently being refurbished for the installation of a 5
MV high-current Pelletron accelerator. Construction work is on schedule and
expected to complete in August 2017. The accelerator will provide intense, 50
uA, beams of 1H+, 4He+, and 12C+ ions, enabling research on astrophysically
relevant nuclear reactions with unprecedented sensitivity.


title:
The Projected Power Method: An Efficient Algorithm for Joint Alignment
  from Pairwise Differences

abstract:
  Various applications involve assigning discrete label values to a collection
of objects based on some pairwise noisy data. Due to the discrete---and hence
nonconvex---structure of the problem, computing the optimal assignment
(e.g.~maximum likelihood assignment) becomes intractable at first sight. This
paper makes progress towards efficient computation by focusing on a concrete
joint alignment problem---that is, the problem of recovering $n$ discrete
variables $x_i \in \{1,\cdots, m\}$, $1\leq i\leq n$ given noisy observations
of their modulo differences $\{x_i - x_j~\mathsf{mod}~m\}$. We propose a
low-complexity and model-free procedure, which operates in a lifted space by
representing distinct label values in orthogonal directions, and which attempts
to optimize quadratic functions over hypercubes. Starting with a first guess
computed via a spectral method, the algorithm successively refines the iterates
via projected power iterations. We prove that for a broad class of statistical
models, the proposed projected power method makes no error---and hence
converges to the maximum likelihood estimate---in a suitable regime. Numerical
experiments have been carried out on both synthetic and real data to
demonstrate the practicality of our algorithm. We expect this algorithmic
framework to be effective for a broad range of discrete assignment problems.

categories: cs.IT cs.CV cs.LG math.IT math.OC stat.ML


title: Toward a Science of Autonomy for Physical Systems: Transportation

abstract:
  Transportation systems are currently being transformed by advances in
information and communication technologies. The development of autonomous
transportation holds the promise of providing revolutionary improvements in
speed, efficiency, safety and reliability along with concomitant benefits for
society and economy. It is anticipated these changes will soon affect household
activity patterns, public safety, supply chains and logistics, manufacturing,
and quality of life in general.


title:
Selectively (a)-spaces from almost disjoint families are necessarily
  countable under a certain parametrized weak diamond principle

abstract:
  The second author has recently shown ([20]) that any selectively (a) almost
disjoint family must have cardinality strictly less than $2^{\alpeh_0}$, so
under the Continuum Hypothesis such a family is necessarily countable. However,
it is also shown in the same paper that $2^{\alpeh_0} < 2^{\alpeh_1}$ alone
does not avoid the existence of uncountable selectively (a) almost disjoint
families. We show in this paper that a certain effective parametrized weak
diamond principle is enough to ensure countability of the almost disjoint
family in this context. We also discuss the deductive strength of this specific
weak diamond principle (which is consistent with the negation of the Continuum
Hypothesis, apart from other features).


title:
Principles and design of a Zeeman-Sisyphus decelerator for molecular
  beams

abstract:
  We explore a technique for decelerating molecules using a static magnetic
field and optical pumping. Molecules travel through a spatially varying
magnetic field and are repeatedly pumped into a weak-field seeking state as
they move towards each strong field region, and into a strong-field seeking
state as they move towards weak field. The method is time-independent and so is
suitable for decelerating both pulsed and continuous molecular beams. By using
guiding magnets at each weak field region, the beam can be simultaneously
guided and decelerated. By tapering the magnetic field strength in the strong
field regions, and exploiting the Doppler shift, the velocity distribution can
be compressed during deceleration. We develop the principles of this
deceleration technique, provide a realistic design, use numerical simulations
to evaluate its performance for a beam of CaF, and compare this performance to
other deceleration methods.


title: List 3-dynamic coloring of graphs with small maximum average degree

abstract:
  An $r$-dynamic $k$-coloring of a graph $G$ is a proper $k$-coloring such that
for any vertex $v$, there are at least $\min\{r,\deg_G(v) \}$ distinct colors
in $N_G(v)$. The $r$-dynamic chromatic number $\chi_r^d(G)$ of a graph $G$ is
the least $k$ such that there exists an $r$-dynamic $k$-coloring of $G$. The
{\em list $r$-dynamic chromatic number} of a graph $G$ is denoted by
$ch_r^d(G)$. Recently, Loeb et al. [UI] showed that the list $3$-dynamic
chromatic number of a planar graph is at most 10. And Cheng et al. [Lai-16]
studied the maximum average condition to have $\chi_3^d (G) \leq 4, \ 5$, or
$6$. On the other hand, Song et al. [SLW] showed that if $G$ is planar with
girth at least 6, then $\chi_r^d(G)\le r+5$ for any $r\ge 3$.
  In this paper, we study list 3-dynamic coloring in terms of maximum average
degree. We show that $ch^d_3(G) \leq 6$ if $mad(G) < \frac{18}{7}$, $ch^d_3(G)
\leq 7$ if $mad(G) < \frac{14}{5}$, and $ch^d_3(G) \leq 8$ if $mad(G) < 3$. All
of the bounds are tight.


title:
Gravitational correlation, black hole entropy and information
  conservation

abstract:
  When two objects have gravitational interaction between them, they are no
longer independent of each other. In fact, there exists gravitational
correlation between these two objects. Inspired by E. Verlinde's paper, we
first calculate the entropy change of a system when gravity does positive work
on this system. Based on the concept of gravitational correlation entropy, we
prove that the entropy of a Schwarzschild black hole originates from the
gravitational correlations between the interior matters of the black hole. By
analyzing the gravitational correlation entropies in the process of Hawking
radiation in a general context, we prove that the reduced entropy of a black
hole is exactly carried away by the radiation and the gravitational
correlations between these radiating particles, and the entropy or information
is conserved at all times during Hawking radiation. Finally, we attempt to give
a unified description of the non-extensive black-hole entropy and the extensive
entropy of ordinary matter.


title: A bound on the primes of bad reduction for CM curves of genus 3

abstract:
  We give bounds on the primes of geometric bad reduction for curves of genus
three of primitive CM type in terms of the CM orders. In the case of genus one,
there are no primes of geometric bad reduction because CM elliptic curves are
CM abelian varieties, which have potential good reduction everywhere. However,
for genus at least two, the curve can have bad reduction at a prime although
the Jacobian has good reduction. Goren and Lauter gave the first bound in the
case of genus two.
  In the cases of hyperelliptic and Picard curves, our results imply bounds on
primes appearing in the denominators of invariants and class polynomials, which
are important for algorithmic construction of curves with given characteristic
polynomials over finite fields.


title: Geodesically complete BTZ-type solutions of $2+1$ Born-Infeld gravity

abstract:
  We study Born-Infeld gravity coupled to a static, nonrotating electric field
in $2+1$ dimensions and find exact analytical solutions. Two families of such
solutions represent geodesically complete, and hence nonsingular, spacetimes.
Another family represents a point-like charge with a singularity at the center.
Despite the absence of rotation, these solutions resemble the charged, rotating
BTZ solution of General Relativity but with a richer structure in terms of
horizons. The nonsingular character of the first two families turn out to be
attached to the emergence of a wormhole structure on their innermost region.
This seems to be a generic prediction of extensions of General Relativity
formulated in metric-affine (or Palatini) spaces, where metric and connection
are regarded as independent degrees of freedom.


title:
$P_1$-nonconforming divergence-free finite element method on square
  meshes for Stokes equations

abstract:
  Recently, the $P_1$-nonconforming finite element space over square meshes has
been proved stable to solve Stokes equations with the piecewise constant space
for velocity and pressure, respectively. In this paper, we will introduce its
locally divergence-free subspace to solve the elliptic problem for the velocity
only decoupled from the Stokes equation. The concerning system of linear
equations is much smaller compared to the Stokes equations. Furthermore, it is
split into two smaller ones. After solving the velocity first, the pressure in
the Stokes problem can be obtained by an explicit method very rapidly.


title:
Context-free grammars for several polynomials associated with Eulerian
  polynomials

abstract:
  In this paper, we present grammatical descriptions of several polynomials
associated with Eulerian polynomials, including q-Eulerian polynomials,
alternating run polynomials and derangement polynomials. As applications, we
get several convolution formulas involving these polynomials.


title: Circuit Breakers, Discovery, and API Gateways in Microservices

abstract:
  We review some of the most widely used patterns for the programming of
microservices: circuit breaker, service discovery, and API gateway. By
systematically analysing different deployment strategies for these patterns, we
reach new insight especially for the application of circuit breakers. We also
evaluate the applicability of Jolie, a language for the programming of
microservices, for these patterns and report on other standard frameworks
offering similar solutions. Finally, considerations for future developments are
presented.


title: Cache-Aided Coded Multicast for Correlated Sources

abstract:
  The combination of edge caching and coded multicasting is a promising
approach to improve the efficiency of content delivery over cache-aided
networks. The global caching gain resulting from content overlap distributed
across the network in current solutions is limited due to the increasingly
personalized nature of the content consumed by users. In this paper, the
cache-aided coded multicast problem is generalized to account for the
correlation among the network content by formulating a source compression
problem with distributed side information. A correlation-aware achievable
scheme is proposed and an upper bound on its performance is derived. It is
shown that considerable load reductions can be achieved, compared to state of
the art correlation-unaware schemes, when caching and delivery phases
specifically account for the correlation among the content files.


title: Bounds for VIX Futures given S&P 500 Smiles

abstract:
  We derive sharp bounds for the prices of VIX futures using the full
information of S&P 500 smiles. To that end, we formulate the model-free
sub/superreplication of the VIX by trading in the S&P 500 and its vanilla
options as well as the forward-starting log-contracts. A dual problem of
minimizing/maximizing certain risk-neutral expectations is introduced and shown
to yield the same value.
  The classical bounds for VIX futures given the smiles only use a calendar
spread of log-contracts on the S&P 500. We analyze for which smiles the
classical bounds are sharp and how they can be improved when they are not. In
particular, we introduce a family of functionally generated portfolios which
often improves the classical bounds while still being tractable; more
precisely, determined by a single concave/convex function on the line.
Numerical experiments on market data and SABR smiles show that the classical
lower bound can be improved dramatically, whereas the upper bound is often
close to optimal.


title: Riesz-Kantorovich formulas for operators on multi-wedged spaces

abstract:
  We introduce the notions of multi-suprema and multi-infima for vector spaces
equipped with a collection of wedges, generalizing the notions of suprema and
infima in ordered vector spaces. Multi-lattices are vector spaces closed under
multi-suprema and multi-infima and are thus an abstraction of vector lattices.
The Riesz decomposition property in the multi-wedged setting is also
introduced, leading to Riesz-Kantorovich formulas for multi-suprema and
multi-infima in certain spaces of operators.


title: On Support Relations and Semantic Scene Graphs

abstract:
  Scene understanding is a popular and challenging topic in both computer
vision and photogrammetry. Scene graph provides rich information for such scene
understanding. This paper presents a novel approach to infer such relations and
then to construct the scene graph. Support relations are estimated by
considering important, previously ignored information: the physical stability
and the prior support knowledge between object classes. In contrast to previous
methods for extracting support relations, the proposed approach generates more
accurate results, and does not require a pixel-wise semantic labeling of the
scene. The semantic scene graph which describes all the contextual relations
within the scene is constructed using this information. To evaluate the
accuracy of these graphs, multiple different measures are formulated. The
proposed algorithms are evaluated using the NYUv2 database. The results
demonstrate that the inferred support relations are more precise than
state-of-the-art. The scene graphs are compared against ground truth graphs.


title: Scope for Machine Learning in Digital Manufacturing

abstract:
  This provocation paper provides an overview of the underlying optimisation
problem in the emerging field of Digital Manufacturing. Initially, this paper
discusses how the notion of Digital Manufacturing is transforming from a term
describing a suite of software tools for the integration of production and
design functions towards a more general concept incorporating computerised
manufacturing and supply chain processes, as well as information collection and
utilisation across the product life cycle. On this basis, we use the example of
one such manufacturing process, Additive Manufacturing, to identify an
integrated multi-objective optimisation problem underlying Digital
Manufacturing. Forming an opportunity for a concurrent application of data
science and optimisation, a set of challenges arising from this problem is
outlined.


title: Correlation-Aware Distributed Caching and Coded Delivery

abstract:
  Cache-aided coded multicast leverages side information at wireless edge
caches to efficiently serve multiple groupcast demands via common multicast
transmissions, leading to load reductions that are proportional to the
aggregate cache size. However, the increasingly unpredictable and personalized
nature of the content that users consume challenges the efficiency of existing
caching-based solutions in which only exact content reuse is explored. This
paper generalizes the cache-aided coded multicast problem to a source
compression with distributed side information problem that specifically
accounts for the correlation among the content files. It is shown how joint
file compression during the caching and delivery phases can provide load
reductions that go beyond those achieved with existing schemes. This is
accomplished through a lower bound on the fundamental rate-memory trade-off as
well as a correlation-aware achievable scheme, shown to significantly
outperform state-of-the-art correlation-unaware solutions, while approaching
the limiting rate-memory trade-off.


title: Leptogenesis in a $\Delta(27) \times SO(10)$ SUSY GUT

abstract:
  Although $SO(10)$ Supersymmetric (SUSY) Grand Unification Theories (GUTs) are
very attractive for neutrino mass and mixing, it is often quite difficult to
achieve successful leptogenesis from the lightest right-handed neutrino $N_1$
due to the strong relations between neutrino and up-type quark Yukawa
couplings. We show that in a realistic model these constraints are relaxed,
making $N_1$ leptogenesis viable. To illustrate this, we calculate the baryon
asymmetry of the Universe $ Y_B $ from flavoured $ N_1 $ leptogenesis in a
recently proposed $ \Delta(27) \times SO(10) $ SUSY GUT. The flavoured
Boltzmann equations are solved numerically, and comparison with the observed $
Y_B $ places constraints on the allowed values of right-handed neutrino masses
and neutrino Yukawa couplings. The flavoured $SO(10)$ SUSY GUT is not only
fairly complete and predictive in the lepton sector, but can also explain the
BAU through leptogenesis with natural values in the lepton sector albeit with
some tuning in the quark sector.


title: Deformation of crystals: Connections with statistical physics

abstract:
  We give a bird's-eye view of the plastic deformation of crystals aimed at the
statistical physics community, and a broad introduction into the statistical
theories of forced rigid systems aimed at the plasticity community. Memory
effects in magnets, spin glasses, charge density waves, and dilute colloidal
suspensions are discussed in relation to the onset of plastic yielding in
crystals. Dislocation avalanches and complex dislocation tangles are discussed
via a brief introduction to the renormalization group and scaling. Analogies to
emergent scale invariance in fracture, jamming, coarsening, and a variety of
depinning transitions are explored. Dislocation dynamics in crystals challenges
non equilibrium statistical physics. Statistical physics provides both
cautionary tales of subtle memory effects in nonequilibrium systems, and
systematic tools designed to address complex scale-invariant behavior on
multiple length and time scales.


title: Weighted Lattice Walks and Universality Classes

abstract:
  In this work we consider two different aspects of weighted walks in cones. To
begin we examine a particular weighted model, known as the Gouyou-Beauchamps
model. Using the theory of analytic combinatorics in several variables we
obtain the asymptotic expansion of the total number of Gouyou-Beauchamps walks
confined to the quarter plane. Our formulas are parametrized by weights and
starting point, and we identify six different asymptotic regimes (called
universality classes) which arise according to the values of the weights. The
weights allowed in this model satisfy natural algebraic identities permitting
an expression of the weighted generating function in terms of the generating
function of unweighted walks on the same steps. The second part of this article
explains these identities combinatorially for walks in arbitrary cones and
dimensions, and provides a characterization of universality classes for general
weighted walks. Furthermore, we describe an infinite set of models with
non-D-finite generating function.


title:
Observability and controllability analysis of linear systems subject to
  data losses

abstract:
  We provide algorithmically verifiable necessary and sufficient conditions for
fundamental system theoretic properties of discrete time linear systems subject
to data losses. More precisely, the systems in our modeling framework are
subject to disruptions (data losses) in the feedback loop, where the set of
possible data loss sequences is captured by an automaton. As such, the results
are applicable in the context of shared (wireless) communication networks
and/or embedded architectures where some information on the data loss behaviour
is available a priori. We propose an algorithm for deciding observability (or
the absence of it) for such systems, and show how this algorithm can be used
also to decide other properties including constructibility, controllability,
reachability, null-controllability, detectability and stabilizability by means
of relations that we establish among these properties. The main apparatus for
our analysis is the celebrated Skolem Theorem from linear algebra. Moreover, we
study the relation between the model adopted in this paper and a previously
introduced model where, instead of allowing dropouts in the feedback loop, one
allows for time varying delays.


title:
Comparing the influence of distinct kinds of temporal disorder in a low
  dimensional absorbing transition model

abstract:
  Recently one has stated that temporal disorder constitutes a relevant
perturbation in absorbing phase transitions for all dimensions. However, its
effect for systems other than the standard contact process (CP), its
competition with other ingredients (e.g. particle diffusion) and other kinds of
disorder (besides the standard types) are unknown. In order to shed some light
in the above mentioned points, we investigate a variant of the usual CP, namely
triplet annihilation model (TAM), in which the competition between triplet
annihilation and single particle diffusion leads to an unusual phase diagram
behavior, with reentrant shape and endless activity for sufficient large
diffusion rates. Two kinds of time-dependent disorder have been considered. In
the former, it is introduced in the creation-annihilation parameters (as
commonly considered in recent studies), whereas in the latter the diffusion
rate $D$ (so far unexplored) is allowed to be time dependent. In all cases, the
disorder follows an uniform distribution with fixed mean and width $\sigma$.
Two values of $\sigma$ have been considered, in order to exemplify the regime
of "weaker" and "stronger" temporal disorder strengths. Our results show that
in the former approach, the disorder suppresses the reentrant phase diagram
with a critical behavior deviating from the directed percolation universality
class (DP) in the regime of low diffusion rates, while they strongly suggest
that the DP class is recovered for larger hoping rates. An opposite scenario is
found in the latter disorder approach, with a substantial increase of reentrant
shape and the maximum diffusion, in which the reentrant shape also displays a
critical behavior consistent to the DP universality class (in similarity with
the pure model). Lastly, comparison with the diffusive disordered CP has been
undertaken.


title:
Angular Structure of Jet Quenching Within a Hybrid Strong/Weak Coupling
  Model

abstract:
  Within the context of a hybrid strong/weak coupling model of jet quenching,
we study the modification of the angular distribution of the energy within jets
in heavy ion collisions, as partons within jet showers lose energy and get
kicked as they traverse the strongly coupled plasma produced in the collision.
To describe the dynamics transverse to the jet axis, we add the effects of
transverse momentum broadening into our hybrid construction, introducing a
parameter $K\equiv \hat q/T^3$ that governs its magnitude. We show that,
because of the quenching of the energy of partons within a jet, even when
$K\neq 0$ the jets that survive with some specified energy in the final state
are narrower than jets with that energy in proton-proton collisions. For this
reason, many standard observables are rather insensitive to $K$. We propose a
new differential jet shape ratio observable in which the effects of transverse
momentum broadening are apparent. We also analyze the response of the medium to
the passage of the jet through it, noting that the momentum lost by the jet
appears as the momentum of a wake in the medium. After freezeout this wake
becomes soft particles with a broad angular distribution but with net momentum
in the jet direction. We show that the particles coming from the response of
the medium to the momentum and energy deposited in it leads to a correlation
between the momentum of soft particles well separated from the jet in angle
with the direction of the jet momentum, and find qualitative but not
quantitative agreement with experimental data on observables designed to
extract such a correlation. By confronting the results that we obtain upon
introducing transverse momentum broadening and the response of the medium to
the jet with available jet data, we highlight the importance of these processes
for understanding the internal, soft, angular structure of high energy jets.


title: Limiting distribution of eigenvalues in the large sieve matrix

abstract:
  The large sieve inequality is equivalent to the bound $\lambda_1 \leqslant N
+ Q^2-1$ for the largest eigenvalue $\lambda_1$ of the $N$ by $N$ matrix
$A^{\star} A$, naturally associated to the positive definite quadratic form
arising in the inequality. For arithmetic applications the most interesting
range is $N \asymp Q^2$. Based on his numerical data Ramar\'e conjectured that
when $N \sim \alpha Q^2$ as $Q \rightarrow \infty$ for some finite positive
constant $\alpha$, the limiting distribution of the eigenvalues of $A^{\star}
A$, scaled by $1/N$, exists and is non-degenerate.
  In this paper we prove this conjecture by establishing the convergence of all
moments of the eigenvalues of $A^{\star} A$ as $Q\rightarrow\infty$. Previously
only the second moment was known, due to Ramar\'e. Furthermore, we obtain an
explicit description of the moments of the limiting distribution, and establish
that they vary continuously with $\alpha$. Some of the main ingredients in our
proof include the large-sieve inequality and results on $n$-correlations of
Farey fractions.


title:
Pulsed VHE emission from the Crab Pulsar in the context of
  magnetocentrifugal particle acceleration

abstract:
  The Crab Pulsar has been recently detected at very high energies (VHE) with
its pulsed VHE emission reaching up to $1.5$ TeV. The VHE peaks appear
synchronised with the peaks at GeV energies and show VHE spectra following hard
power-law functions. These new findings have been interpreted as evidence for a
gamma-ray production that happens very close to the light cylinder. Motivated
by these experimental results we consider the efficiency of magnetocentrifugal
particle acceleration in the magnetosphere of the Crab Pulsar, reexamining and
extending results obtained in a previous work (Osmanov & Rieger 2009). It is
shown that efficient magnetocentrifugal acceleration close to the light
cylinder could provide the required electron Lorentz factors of $5\times 10^6$
and that the resulting inverse Compton (IC) scattering off thermal photons
might explain the enigmatic TeV emission of the pulsar. We estimate the
corresponding VHE luminosity and provide a derivation of its spectral
characteristics, that appear remarkably close to the observational results to
encourage further studies.


title:
Electronic and structural properties of rhombohedral [111] and [110]
  oriented ultra-thin bismuth nanowires

abstract:
  Structures and electronic properties of rhombohedral [111] and [110] bismuth
nanowires are calculated with the use of density functional theory. The
formation of an energy band gap from quantum confinement is studied and to
improve estimates for the band gap the GW approximation is applied. The [111]
oriented nanowires require surface bonds to be chemically saturated to avoid
formation of metallic surface states whereas the surface of the [110] nanowires
do not support metallic surface states. It is found that the onset of quantum
confinement in the surface passivated [111] nanowires occurs at larger critical
dimensions than for the [110] nanowires. For the [111] oriented nanowires it is
predicted that a band gap of approximately 0.5 eV can be formed at a diameter
of approximately 6 nm, whereas for the [110] oriented nanowires a diameter of
approximately 3 nm is required to achieve a similar band gap energy. The GW
correction is also applied to estimates of the electron affinity, ionisation
potentials and work functions for both orientations of the nanowires for
various diameters below 5 nm. The magnitude of the energy band gaps that arise
in bismuth at critical dimensions of a few nanometers are of the same order as
for conventional bulk semiconductors.


title:
Cohomological dimension, Lyubeznik numbers, and connectedness properties
  in mixed characteristic

abstract:
  We establish a "second vanishing theorem" for local cohomology modules over
regular rings of unramified mixed characteristic, which relates the
connectedness of the spectrum of a ring with the vanishing of local cohomology.
Applying this, and new results on the mixed characteristic Lyubeznik numbers,
we further study connectedness properties of the spectra of a certain class of
rings.


title:
A syntactic proof of decidability for the logic of bunched implication
  BI

abstract:
  The logic of bunched implication BI provides a framework for reasoning about
resource composition and forms the basis for an assertion language of
separation logic which is used to reason about software programs. Propositional
BI is obtained by freely combining propositional intuitionistic logic and
multiplicative intuitionistic linear logic. It possesses an elegant proof
theory: its bunched calculus combines the sequent calculi for these logics.
Several natural extensions of BI have been shown as undecidable, e.g. Boolean
BI which replaces intuitionistic logic with classical logic. This makes the
decidability of BI, proved recently via an intricate semantical argument,
particularly noteworthy. However, a syntactic proof of decidability has thus
far proved elusive. We obtain such a proof here using a proof-theoretic
argument. The proof is technically interesting, accessible as it uses the usual
bunched calculus (it does not require any knowledge of the semantics of BI),
yields an implementable decision procedure and implies an upper bound on the
complexity of the logic.


title: Thermodynamics of quantum information scrambling

abstract:
  Scrambling of quantum information can be conveniently quantified by so called
out-of-time-order-correlators (OTOCs), whose measurements presents a formidable
experimental challenge. Here we report on a method for the measurement of OTOCs
based on the so-called two-point measurements scheme developed in the field of
non-equilibrium quantum thermodynamics. The scheme is of broader applicability
than methods employed in current experiments and also provides a clear-cut
interpretation of quantum information scrambling in terms of non-equilibrium
fluctuations of thermodynamic quantities such as work. Furthermore, we provide
a numerical example on a spin chain which highlights the utility of our
thermodynamic approach when understanding the differences between integrable
and ergodic behavior. We also discuss connections to some recent experiments.


title:
Starobinsky-Like Inflation and Neutrino Masses in a No-Scale SO(10)
  Model

abstract:
  Using a no-scale supergravity framework, we construct an SO(10) model that
makes predictions for cosmic microwave background observables similar to those
of the Starobinsky model of inflation, and incorporates a double-seesaw model
for neutrino masses consistent with oscillation experiments and late-time
cosmology. We pay particular attention to the behaviour of the scalar fields
during inflation and the subsequent reheating.


title:
Photometric Monitoring of the Coldest Known Brown Dwarf with the Spitzer
  Space Telescope

abstract:
  Because WISE J085510.83$-$071442.5 (hereafter WISE 0855-0714) is the coldest
known brown dwarf ($\sim250$ K) and one of the Sun's closest neighbors (2.2
pc), it offers a unique opportunity for studying a planet-like atmosphere in an
unexplored regime of temperature. To detect and characterize inhomogeneities in
its atmosphere (e.g., patchy clouds, hot spots), we have performed time-series
photometric monitoring of WISE 0855-0714 at 3.6 and 4.5 micron with the Spitzer
Space Telescope during two 23~hr periods that were separated by several months.
For both bands, we have detected variability with peak-to-peak amplitudes of
4-5% and 3-4% in the first and second epochs, respectively. The light curves
are semi-periodic in the first epoch for both bands, but are more irregular in
the second epoch. Models of patchy clouds have predicted a large increase in
mid-IR variability amplitudes (for a given cloud covering fraction) with the
appearance of water ice clouds at $T_{\rm eff}<$375 K, so if such clouds are
responsible for the variability of WISE 0855-0714, then its small amplitudes of
variability indicate a very small deviation in cloud coverage between
hemispheres. Alternatively, the similarity in mid-IR variability amplitudes
between WISE 0855-0714 and somewhat warmer T and Y dwarfs may suggest that they
share a common origin for their variability (i.e., not water clouds). In
addition to our variability data, we have examined other constraints on the
presence of water ice clouds in the atmosphere of WISE 0855-0714, including the
recent mid-IR spectrum from \citet{ske16}. We find that robust evidence of such
clouds is not yet available.


title: Three-Point Vortex Dynamics as a Lie-Poisson System

abstract:
  This paper studies the reduced dynamics of the three-vortex problem from the
point of view of Lie-Poisson reduction on the dual of the Lie algebra of $ U(2)
$. The algebraic study leading to this point of view has been given by Borisov
and Lebedev 1998 (see also Bolsinov, Borisov and Mamaev 1999). The main
contribution of this paper is to properly describe the dynamics as a
Lie-Poisson reduced system on $ (\mathfrak{u}(2) ^\ast, \{\;,\,\}_{\text{LP}} )
$, giving a systematic construction of a one-parameter family of covectors $ \{
\sigma _1, \sigma _2, \sigma _3 \} $ closely related to Pauli spin matrices,
and to bring light to the relation between Lie-Poisson reduction and symplectic
reduction using Jacobi-Bertrand-Haretu coordinates.


title: Flexural phonon scattering induced by electrostatic gating in graphene

abstract:
  Graphene has an extremely high carrier mobility partly due to its planar
mirror symmetry inhibiting scattering by the highly occupied acoustic flexural
phonons. Electrostatic gating of a graphene device can break the planar mirror
symmetry yielding a coupling mechanism to the flexural phonons. We examine the
effect of the gate-induced one-phonon scattering on the mobility for several
gate geometries and dielectric environments using first-principles calculations
based on density functional theory (DFT) and the Boltzmann equation. We
demonstrate that this scattering mechanism can be a mobility-limiting factor,
and show how the carrier density and temperature scaling of the mobility
depends on the electrostatic environment. Our findings may explain the high
deformation potential for in-plane acoustic phonons extracted from experiments
and furthermore suggest a direct relation between device symmetry and resulting
mobility.


title:
Weak solution of a continuum model for vicinal surface in the
  attachment-detachment-limited regime

abstract:
  We study in this work a continuum model derived from 1D
attachment-detachment-limited (ADL) type step flow on vicinal surface, $
u_t=-u^2(u^3)_{hhhh}$, where $u$, considered as a function of step height $h$,
is the step slope of the surface. We formulate a notion of weak solution to
this continuum model and prove the existence of a global weak solution, which
is positive almost everywhere. We also study the long time behavior of weak
solution and prove it converges to a constant solution as time goes to
infinity. The space-time H\"older continuity of the weak solution is also
discussed as a byproduct.


title: Brushing Number and Zero-Forcing Number of Graphs and their Line Graphs

abstract:
  In this paper we compare the brushing number of a graph with the zero-forcing
number of its line graph. We prove that the zero-forcing number of the line
graph is an upper bound for the brushing number by constructing a brush
configuration based on a zero-forcing set for the line graph. Using a similar
construction, we also prove the conjecture that the zero-forcing number of a
graph is no more than the zero-forcing number of its line graph; moreover we
prove that the brushing number of a graph is no more than the brushing number
of its line graph. All three bounds are shown to be tight.


title:
Switching ferromagnetic spins by an ultrafast laser pulse: Emergence of
  giant optical spin-orbit torque

abstract:
  Faster magnetic recording technology is indispensable to massive data storage
and big data sciences. {All-optical spin switching offers a possible solution},
but at present it is limited to a handful of expensive and complex rare-earth
ferrimagnets. The spin switching in more abundant ferromagnets may
significantly expand the scope of all-optical spin switching. Here by studying
40,000 ferromagnetic spins, we show that it is the optical spin-orbit torque
that determines the course of spin switching in both ferromagnets and
ferrimagnets. Spin switching occurs only if the effective spin angular momentum
of each constituent in an alloy exceeds a critical value. Because of the strong
exchange coupling, the spin switches much faster in ferromagnets than
weakly-coupled ferrimagnets. This establishes a paradigm for all-optical spin
switching. The resultant magnetic field (65 T) is so big that it will
significantly reduce high current in spintronics, thus representing the
beginning of photospintronics.


title:
Unbiased constraints on ultralight axion mass from dwarf spheroidal
  galaxies

abstract:
  It has been suggested that the internal dynamics of dwarf spheroidal galaxies
(dSphs) can be used to test whether or not ultralight axions with $m_a\sim
10^{-22}\text{eV}$ are a preferred dark matter candidate. However, comparisons
to theoretical predictions tend to be inconclusive for the simple reason that
while most cosmological models consider only dark matter, one observes only
baryons. Here we use realistic kinematic mock data catalogs of Milky Way dSph's
to show that the "mass-anisotropy degeneracy" in the Jeans equations leads to
biased bounds on the axion mass in galaxies with unknown dark matter halo
profiles. In galaxies with multiple chemodynamical components this bias can be
partly removed by modelling the mass enclosed within each subpopulation.
However, analysis of the mock data reveals that the least-biased constraints on
the axion mass result from fitting the luminosity-averaged velocity dispersion
of the individual chemodynamical components directly. Applying our analysis to
two dSph's with reported stellar subcomponents, Fornax and Sculptor, and
assuming that the halo profile has not been acted on by baryons, yields core
radii $r_{c}>1.5$ kpc and $r_c> 1.2$ kpc respectively, and $m_a<0.4\times
10^{-22}\text{eV}$ at 97.5\% confidence. These bounds are in tension with the
number of observed satellites derived from simple (but conservative) estimates
of the subhalo mass function in Milky Way-like galaxies. We discuss how
baryonic feedback might affect our results, and the impact of such a small
axion mass on the growth of structures in the Universe.


title:
Scaling theory of the Anderson transition in random graphs: ergodicity
  and universality

abstract:
  We study the Anderson transition on a generic model of random graphs with a
tunable branching parameter $1<K\le 2$, through large scale numerical
simulations and finite-size scaling analysis. We find that a single transition
separates a localized phase from an unusual delocalized phase which is ergodic
at large scales but strongly non-ergodic at smaller scales. In the critical
regime, multifractal wavefunctions are located on few branches of the graph.
Different scaling laws apply on both sides of the transition: a scaling with
the linear size of the system on the localized side, and an unusual volumic
scaling on the delocalized side. The critical scalings and exponents are
independent of the branching parameter, which strongly supports the
universality of our results.

categories: cond-mat.stat-mech cond-mat.dis-nn math.PR quant-ph


title:
Phonon-limited electrical transport properties of intermetallic compound
  YbAl3 from first-principles calculations

abstract:
  We combine first-principles calculations and Boltzmann transport theory to
study the electrical transport properties of intermetallic compound YbAl3. To
accurately predict the electronic relaxation time, we use the density
functional perturbation theory and Wannier interpolation techniques which can
effectively treat the electron-phonon scattering. Our calculated transport
coefficients of YbAl3 are in reasonable agreement with the experimentally
measured results. Strikingly, we discover that in evaluating the Seebeck
coefficient of YbAl3, the scattering term has a larger contribution than the
band term and should be explicitly considered in the calculations, especially
for the case with localized bands near the Fermi level. Moreover, we
demonstrate that by reducing the sample size to less than ~30 nm, the
electronic thermal conductivity of YbAl3 can be sufficiently suppressed so that
the thermoelectric figure of merit can be further enhanced.


title:
Spin-dependent transport and current modulation in a current-in-plane
  field-effect transistor

abstract:
  We propose a current-in-plane spin-valve field-effect transistor
(CIP-SV-FET), which is composed of a ferromagnet / nonferromagnet / ferromagnet
trilayer structure and a gate electrode. This is a promising device alternative
to spin metal-oxide-semiconductor field-effect transistors. Here, we fabricate
a ferromagnetic-semiconductor GaMnAs-based CIP-SV-FET and demonstrate its basic
operation of the resistance modulation both by the magnetization configuration
and by the gate electric field. Furthermore, we present the
electric-field-assisted magnetization reversal in this device.


title: Influence of solar flares on behavior of solar neutrino flux

abstract:
  Limiting ourselves to two flavor approximation the motion of the neutrino
flux in the solar matter and twisting magnetic field is considered. For the
neutrino system described by the 4-component wave function $\Psi^T = (\nu_{eL},
\nu_{XL}, {\overline\nu}_{eR}, {\overline\nu}_{XL})$, where $X=\mu, \tau$, an
evolution equation is found. Our consideration carries general character, that
is, it holds for any SM extensions with massive neutrinos. The resonance
transitions of the electron neutrinos are investigated. Factors which influence
on the electron neutrino flux, crossing a region of solar flares (SF) are
defined. When the SF is absent a terrestrial detector records the electron
neutrino flux weakened at the cost both of vacuum oscillations and of the MSW
resonance conversion only. On the other hand, the electron neutrino flux passed
the SF region in preflare period proves to be further weakened in so far as it
undergoes one (Majorana neutrino) or two (Dirac neutrino) additional resonance
conversions, apart from the MSW resonance and vacuum oscillations. The
hypothesis of the $\nu_e$-induced decays which states that decreasing the beta
decay rates of some elements of the periodic table is caused by reduction of
the solar neutrino flux is discussed as well.
  PACS number(s): 12.60.Cn, 14.60.Pg, 96.60.Kx, 95.85.Qx, 96.60.Rd.


title:
All-Optical Detection of Acoustic Pressure Waves with applications in
  Photo-Acoustic Spectroscopy

abstract:
  An all-optical detection method for the detection of acoustic pressure waves
is demonstrated. The detection system is based on a stripped (bare) single-mode
fiber. The fiber vibrates as a standard cantilever and the optical output from
the fiber is imaged to a displacement-sensitive optical detector. The absence
of a conventional microphone makes the demonstrated system less susceptible to
the effects that a hazardous environment might have on the sensor. The sensor
is also useful for measurements in high temperature (above $200^{\circ}$C)
environments where conventional microphones will not operate. The
proof-of-concept of the all-optical detection method is demonstrated by
detecting sound waves generated by the photo-acoustic effect of NO$_2$ excited
by a 455 nm LED, where a detection sensitivity of approximately 50 ppm was
achieved.


title:
The physics mechanisms of light and heavy flavor $v_{2}$ and mass
  ordering in AMPT

abstract:
  A Multi-Phase Transport (AMPT) model has been shown to describe experimental
data well, such as the bulk properties of particle spectra and elliptic
anisotropy ($v_{2}$) in heavy ion collisions. Recent studies have shown that
AMPT describes the $v_{2}$ data in small system collisions as well. In these
proceedings, we first investigate the origin of the mass ordering of identified
hadrons $v_{2}$ in heavy ion as well as small system collisions. We then study
the production mechanism of the charm $v_{2}$ in light of the escape mechanism
for the light quark $v_{2}$.


title: Multiple zeta values and Euler sums

abstract:
  In this paper, we establish some expressions of series involving harmonic
numbers and Stirling numbers of the first kind in terms of multiple zeta
values, and present some new relationships between multiple zeta values and
multiple zeta star values. The relationships obtained allow us to find some
nice closed form representations of nonlinear Euler sums through Riemann zeta
values and linear sums. Furthermore, we show that the combined sums \[H\left(
{a,b;m,p} \right) := \sum\limits_{a + b = m - 1} {\zeta \left( {{{\left\{ p
\right\}}_a},p + 1,{{\left\{ p \right\}}_b}} \right)}\quad (m\in \N,p>1) \] and
\[{H^ \star }\left( {a,b;m,p} \right) := \sum\limits_{a + b = m - 1} {{\zeta ^
\star }\left( {{{\left\{ p \right\}}_a},p + 1,{{\left\{ p \right\}}_b}}
\right)}\quad (m\in \N,p>1) \] are reducible to polynomials in zeta values, and
give explicit recurrence formulas. Some interesting (known or new) consequences
and illustrative examples are considered.


title:
Reconstruction of the phonon relaxation times using solutions of the
  Boltzmann transport equation

abstract:
  We present a method for reconstructing the phonon relaxation time
distribution $\tau_{\omega}= \tau (\omega)$ (including polarization) in a
material from thermal spectroscopy data. The distinguishing feature of this
approach is that it does not make use of the effective thermal conductivity
concept and associated approximations. The reconstruction is posed as an
optimization problem in which the relaxation times $\tau_{\omega}= \tau
(\omega)$ are determined by minimizing the discrepancy between the experimental
relaxation traces and solutions of the Boltzmann transport equation (BTE) for
the same problem. The latter may be analytical, in which case the procedure is
very efficient, or numerical. The proposed method is illustrated using Monte
Carlo solutions of thermal grating relaxation as synthetic experimental data.
The reconstruction is shown to agree very well with the relaxation times used
to generate the synthetic Monte Carlo data and remains robust in the presence
of uncertainty (noise).


title:
Asymptotic properties of maximum likelihood estimator for the growth
  rate for a jump-type CIR process based on continuous time observations

abstract:
  We consider a jump-type Cox--Ingersoll--Ross (CIR) process driven by a
standard Wiener process and a subordinator, and we study asymptotic properties
of the maximum likelihood estimator (MLE) for its growth rate. We distinguish
three cases: subcritical, critical and supercritical. In the subcritical case
we prove weak consistency and asymptotic normality, and, under an additional
moment assumption, strong consistency as well. In the supercritical case, we
prove strong consistency and mixed normal (but non-normal) asymptotic behavior,
while in the critical case, weak consistency and non-standard asymptotic
behavior are described. We specialize our results to so-called basic affine
jump-diffusions as well. Concerning the asymptotic behavior of the MLE in the
supercritical case, we derive a stochastic representation of the limiting mixed
normal distribution, where the almost sure limit of an appropriately scaled
jump-type supercritical CIR process comes into play. This is a new phenomenon,
compared to the critical case, where a diffusion-type critical CIR process
plays a role.


title:
A Cheap Linear Attention Mechanism with Fast Lookups and Fixed-Size
  Representations

abstract:
  The softmax content-based attention mechanism has proven to be very
beneficial in many applications of recurrent neural networks. Nevertheless it
suffers from two major computational limitations. First, its computations for
an attention lookup scale linearly in the size of the attended sequence.
Second, it does not encode the sequence into a fixed-size representation but
instead requires to memorize all the hidden states. These two limitations
restrict the use of the softmax attention mechanism to relatively small-scale
applications with short sequences and few lookups per sequence. In this work we
introduce a family of linear attention mechanisms designed to overcome the two
limitations listed above. We show that removing the softmax non-linearity from
the traditional attention formulation yields constant-time attention lookups
and fixed-size representations of the attended sequences. These properties make
these linear attention mechanisms particularly suitable for large-scale
applications with extreme query loads, real-time requirements and memory
constraints. Early experiments on a question answering task show that these
linear mechanisms yield significantly better accuracy results than no
attention, but obviously worse than their softmax alternative.


title:
Fully Dynamic Connectivity in $O(\log n(\log\log n)^2)$ Amortized
  Expected Time

abstract:
  Dynamic connectivity is one of the most fundamental problems in dynamic graph
algorithms. We present a new randomized dynamic connectivity structure with
$O(\log n (\log\log n)^2)$ amortized expected update time and $O(\log
n/\log\log\log n)$ query time, which comes within an $O((\log\log n)^2)$ factor
of a lower bound due to \Patrascu{} and Demaine. The new structure is based on
a dynamic connectivity algorithm proposed by Thorup in an extended abstract at
STOC 2000, which left out some important details.


title: Some Notes on Dirac operators on the ${\rm S}^3$ and ${\rm S}^2$ spheres

abstract:
  We describe both the Hodge - de Rham and the spin manifold Dirac operator on
the spheres ${\rm S}^3$ and ${\rm S}^2$, following the formalism introduced by
K\"ahler, and exhibit a complete spectral resolution for them in terms of
suitably globally defined eigenspinors.


title:
Asymptotic behavior of large polygonal Wilson loops in confining gauge
  theories

abstract:
  In the framework of effective string theory (EST), the asymptotic behavior of
a large Wilson loop in confining gauge theories can be expressed via Laplace
determinant with Dirichlet boundary condition on the Wilson contour. For a
general polygonal region, Laplace determinant can be computed using the
conformal anomaly and Schwarz-Christoffel transformation. One can construct
ratios of polygonal Wilson loops whose large-size limit can be expressed via
computable Laplace determinants and is independent of the (confining) gauge
group. These ratios are computed for hexagon polygons both in EST and by Monte
Carlo (MC) lattice simulations for the tree-dimensional lattice Z2 gauge theory
(dual to Ising model) near its critical point. For large hexagon Wilson loops a
perfect agreement is observed between the asymptotic EST expressions and the
lattice MC results.


title: Generalized SU(2) Proca Theory

abstract:
  Following previous works on generalized Abelian Proca theory, also called
vector Galileon, we investigate the massive extension of an SU(2) gauge theory,
i.e., the generalized SU(2) Proca model, which could be dubbed non-Abelian
vector Galileon. This particular symmetry group permits fruitful applications
in cosmology such as inflation driven by gauge fields. Our approach consists in
building, in an exhaustive way, all the Lagrangians containing up to six
contracted Lorentz indices. For this purpose, and after identifying by group
theoretical considerations all the independent Lagrangians which can be written
at these orders, we consider the only linear combinations propagating three
degrees of freedom and having healthy dynamics for their longitudinal mode,
i.e., whose pure St\"uckelberg contribution turns into the SU(2) multi-Galileon
dynamics. Finally, and after having considered the curved space-time expansion
of these Lagrangians, we discuss the form of the theory at all subsequent
orders.


title:
Deep Neural Ensemble for Retinal Vessel Segmentation in Fundus Images
  towards Achieving Label-free Angiography

abstract:
  Automated segmentation of retinal blood vessels in label-free fundus images
entails a pivotal role in computed aided diagnosis of ophthalmic pathologies,
viz., diabetic retinopathy, hypertensive disorders and cardiovascular diseases.
The challenge remains active in medical image analysis research due to varied
distribution of blood vessels, which manifest variations in their dimensions of
physical appearance against a noisy background.
  In this paper we formulate the segmentation challenge as a classification
task. Specifically, we employ unsupervised hierarchical feature learning using
ensemble of two level of sparsely trained denoised stacked autoencoder. First
level training with bootstrap samples ensures decoupling and second level
ensemble formed by different network architectures ensures architectural
revision. We show that ensemble training of auto-encoders fosters diversity in
learning dictionary of visual kernels for vessel segmentation. SoftMax
classifier is used for fine tuning each member auto-encoder and multiple
strategies are explored for 2-level fusion of ensemble members. On DRIVE
dataset, we achieve maximum average accuracy of 95.33\% with an impressively
low standard deviation of 0.003 and Kappa agreement coefficient of 0.708 .
Comparison with other major algorithms substantiates the high efficacy of our
model.


title:
Generalized Einstein-Scalar-Maxwell theories and locally geometric
  U-folds

abstract:
  We give a global formulation of the coupling of four-dimensional scalar sigma
models to Abelian gauge fields for the generalized situation when the "duality
structure" of the Abelian gauge theory is described by a flat symplectic vector
bundle $(\mathcal{S},D,\omega)$ defined over the scalar manifold $\mathcal{M}$.
The construction uses a taming of $(\mathcal{S}, \omega)$, which encodes
globally the inverse gauge couplings and theta angles of the "twisted" Abelian
gauge theory in a manner that makes no use of duality frames. We show that
global solutions of the equations of motion of such models give classical
locally geometric U-folds. We also describe the groups of duality
transformations and scalar-electromagnetic symmetries arising in such models,
which involve lifting isometries of $\mathcal{M}$ to a particular class of flat
automorphisms of the bundle $\mathcal{S}$ and hence differ from expectations
based on local analysis. The appropriate version of the Dirac quantization
condition involves a discrete local system defined over $\mathcal{M}$ and gives
rise to a smooth bundle of polarized Abelian varieties, endowed with a flat
symplectic connection. This shows that a generalization of part of the
mathematical structure familiar from $\mathcal{N}=2$ supergravity is already
present in such purely bosonic models, without any coupling to fermions and
hence without any supersymmetry.


title:
On Closed and Exact Grad-grad- and div-Div-Complexes, Corresponding
  Compact Embeddings for Tensor Rotations, and a Related Decomposition Result
  for Biharmonic Problems in 3D

abstract:
  It is shown that the first biharmonic boundary value problem on a
topologically trivial domain in 3D is equivalent to three (consecutively to
solve) second-order problems. This decomposition result is based on a
Helmholtz-like decomposition of an involved non-standard Sobolev space of
tensor fields and a proper characterization of the operator div-Div acting on
this space. Similar results for biharmonic problems in 2D and their impact on
the construction and analysis of finite element methods have been recently
published by the second author. The discussion of the kernel of div-Div leads
to (de Rham-like) closed and exact Hilbert complexes, the div-Div-complex and
its adjoint the Grad-grad-complex, involving spaces of trace-free and symmetric
tensor fields. For these tensor fields we show Helmholtz type decompositions
and, most importantly, new compact embedding results. Almost all our results
hold and are formulated for general bounded strong Lipschitz domains of
arbitrary topology. There is no reasonable doubt that our results extend to
strong Lipschitz domains in arbitrary dimensions.


title: Dimesoatoms production in high energy collisions

abstract:
  The production of two meson electromagnetic bound states and free meson pairs
$\pi^+\pi^-$, $K^+K^-$, $\pi^+ K^{\mp}$ in relativistic collisions has been
considered. It is shown that making use of the exact Coulomb wave function for
dimesoatom (DMA) allows one to calculate the yield of any nS state with desired
accuracy. The relative probabilities of production of DMA and meson pairs in
the free state are estimated. The amplitude of DMA transition from 1S to 2P
state, which is essential for the pionium Lamb shift measurements, has been
obtained.


title:
Modernizing Quantum Annealing II: Genetic algorithms with the Inference
  Primitive Formalism

abstract:
  Quantum annealing allows for quantum fluctuations to be used used to assist
in finding the solution to some of the worlds most challenging computational
problems. Recently, this field has attracted much interest because of the
construction of large-scale flux-qubit based quantum annealing devices. There
has been recent work on [Chancellor NJP 19(2):023024, 2017] how the control
protocols of these devices can be modified so that individual annealer calls on
real devices can take initial conditions. Development is being undertaken to
implement such protocols in the quantum annealing devices designed by D-Wave
Systems Inc. and these features will be available to customers soon. In this
paper, I develop a formalism for algorithmic design in quantum annealers, which
I call the `inference primitive' formalism. This formalism allows for a natural
description of calls to quantum annealers with a general control structure.
This more generalized control structure includes not only the ability to
include initial conditions in an annealer run, but also to control the
annealing schedules of qubits or clusters of qubits independently, thereby
representing relative certainty values of different parts of a candidate
solution. I discuss the compatability of such controls with a wide variety of
other current efforts to improve the performance of annealers, such as
non-stoquatic drivers, synchronizing freeze times for the qubits, and belief
propagation techniques. To demonstrate the power of the formalism I present
here, I discuss how this new formalism can be used to represent annealer
implementations of genetic algorithms, and can represent the addition of
genetic components to currently used algorithms. The new tools I develop will
allow a more complete understanding of the algorithmic space available to
quantum annealers, and thereby make the field more competitive.


title:
On the Phase Transition of Finding a Biclique in a larger Bipartite
  Graph

abstract:
  We report on the phase transition of finding a complete subgraph, of
specified dimensions, in a bipartite graph. Finding a complete subgraph in a
bipartite graph is a problem that has growing attention in several domains,
including bioinformatics, social network analysis and domain clustering. A key
step for a successful phase transition study is identifying a suitable order
parameter, when none is known. To this purpose, we have applied a decision tree
classifier to real-world instances of this problem, in order to understand what
problem features separate an instance that is hard to solve from those that is
not. We have successfully identified one such order parameter and with it the
phase transition of finding a complete bipartite subgraph of specified
dimensions. Our phase transition study shows an
easy-to-hard-to-easy-to-hard-to-easy pattern. Further, our results indicate
that the hardest instances are in a region where it is more likely that the
corresponding bipartite graph will have a complete subgraph of specified
dimensions, a positive answer. By contrast, instances with a negative answer
are more likely to appear in a region where the computational cost is
negligible. This behaviour is remarkably similar for problems of a number of
different sizes.


title:
Geometrically Convergent Distributed Optimization with Uncoordinated
  Step-Sizes

abstract:
  A recent algorithmic family for distributed optimization, DIGing's, have been
shown to have geometric convergence over time-varying undirected/directed
graphs. Nevertheless, an identical step-size for all agents is needed. In this
paper, we study the convergence rates of the Adapt-Then-Combine (ATC) variation
of the DIGing algorithm under uncoordinated step-sizes. We show that the ATC
variation of DIGing algorithm converges geometrically fast even if the
step-sizes are different among the agents. In addition, our analysis implies
that the ATC structure can accelerate convergence compared to the distributed
gradient descent (DGD) structure which has been used in the original DIGing
algorithm.


title: Young People's Burden: Requirement of Negative CO2 Emissions

abstract:
  Global temperature is a fundamental climate metric highly correlated with sea
level, which implies that keeping shorelines near their present location
requires keeping global temperature within or close to its preindustrial
Holocene range. However, global temperature excluding short-term variability
now exceeds +1degC relative to the 1880-1920 mean and annual 2016 global
temperature was almost +1.3degC. We show that global temperature has risen well
out of the Holocene range and Earth is now as warm as during the prior
interglacial, when sea level reached 6-9 meters higher than today. Further,
Earth is out of energy balance with present atmospheric composition, implying
more warming is in the pipeline, and we show that the growth rate of greenhouse
gas climate forcing has accelerated markedly in the past decade. The rapidity
of ice sheet and sea level response to global temperature is difficult to
predict but is dependent on the magnitude of warming. Targets for limiting
global warming should aim to avoid leaving global temperature at Eemian or
higher levels for centuries. Such targets require "negative emissions",
extraction of CO2 from the air. If phasedown of fossil fuel emissions begins
soon, improved agricultural and forestry practices may provide much of the
extraction, and the magnitude and duration of global temperature excursion
above the natural range of the current interglacial could be limited and
irreversible impacts minimized. In contrast, continued high emissions place a
burden on young people to undertake massive technological CO2 extraction to
limit climate change and its consequences. Proposed methods of extraction have
minimal estimated costs of 89-535 trillion dollars this century and have large
risks and uncertain feasibility. Continued high emissions unarguably sentences
young people to a massive, implausible cleanup, growing deleterious climate
impacts or both.


title:
Online Output-Feedback Parameter and State Estimation for Second Order
  Linear Systems

abstract:
  In this paper, a concurrent learning based adaptive observer is developed for
a class of second-order linear time-invariant systems with uncertain system
matrices. The developed technique yields an exponentially convergent state
estimator and an exponentially convergent parameter estimator. As opposed to
persistent excitation required for parameter convergence in traditional
adaptive methods, excitation over a finite time-interval is sufficient for the
developed technique to achieve exponential convergence. Simulation results in
both noise-free and noisy environments are presented to validate the design.


title: Invariance-like results for Nonautonomous Switched Systems

abstract:
  This paper generalizes the Lasalle-Yoshizawa Theorem to switched nonsmooth
systems. Filippov and Krasovskii regularizations of a switched system are shown
to be contained within the convex hull of the Filippov and Krasovskii
regularizations of the subsystems, respectively. A candidate common Lyapunov
function that has a negative semidefinite derivative along the trajectories of
the subsystems is shown to be sufficient to establish LaSalle-Yoshizawa results
for the switched system. Results for regular and non-regular candidate Lyapunov
functions are presented using an appropriate generalization of the time
derivative. The developed generalization is motivated by adaptive control of
switched systems where the derivative of the candidate Lyapunov function is
typically negative semidefinite.


title:
Online and Distributed learning of Gaussian mixture models by Bayesian
  Moment Matching

abstract:
  The Gaussian mixture model is a classic technique for clustering and data
modeling that is used in numerous applications. With the rise of big data,
there is a need for parameter estimation techniques that can handle streaming
data and distribute the computation over several processors. While online
variants of the Expectation Maximization (EM) algorithm exist, their data
efficiency is reduced by a stochastic approximation of the E-step and it is not
clear how to distribute the computation over multiple processors. We propose a
Bayesian learning technique that lends itself naturally to online and
distributed computation. Since the Bayesian posterior is not tractable, we
project it onto a family of tractable distributions after each observation by
matching a set of sufficient moments. This Bayesian moment matching technique
compares favorably to online EM in terms of time and accuracy on a set of data
modeling benchmarks.


title: Supernova Constraints on Massive (Pseudo)Scalar Coupling to Neutrinos

abstract:
  In this paper we derive constraints on the emission of a massive
(pseudo)scalar $S$ from annihilation of neutrinos in the core of supernovae
through the dimension-4 coupling $\nu\nu S$, as well as the effective
dimension-5 operator $\frac{1}{\Lambda}(\nu\nu)(SS)$. While most of earlier
studies have focused on massless or ultralight scalars, our analysis involves
scalar with masses of order $\mathrm{eV- GeV}$ which can be copiously produced
during the explosion of supernovae, whose core temperature is generally of
order $T\sim \mathcal{O}(10)$ MeV. From the luminosity and deleptonization
arguments regarding the observation of SN1987A, we exclude a large range of
couplings $ 10^{-12} \lesssim {|g_{\alpha\beta}|}\lesssim 10^{-5}$ for the
dimension-4 case, depending on the neutrino flavours involved and the scalar
mass. In the case of dimension-5 operator, for a scalar mass from MeV to 100
MeV the coupling $h_{\alpha\beta}$ get constrained from $10^{-6}$ to $10^{-2}$,
with the cutoff scale explicitly set $\Lambda = 1$ TeV. We finally show that if
the neutrino burst of a nearby supernova explosion is detected by
Super-Kamiokande and IceCube, the constraints will be largely reinforced.

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


title: A UV complete partially composite-pNGB Higgs

abstract:
  We explore an electroweak symmetry breaking (EWSB) scenario based on the
mixture of a fundamental Higgs doublet and an SU(4)/Sp(4) composite
pseudo-Nambu-Goldstone doublet -- a particular manifestation of bosonic
technicolor/induced EWSB. Taking the fundamental Higgs mass parameter to be
positive, EWSB is triggered by the mixing of the doublets. This setup has
several attractive features and phenomenological consequences, which we
highlight: i) Unlike traditional bosonic technicolor models, the hierarchy
between $\Lambda_{\rm TC}$ and the electroweak scale depends on vacuum
(mis)alignment and can be sizable, yielding an attractive framework for natural
EWSB; ii) As the strong sector is based on SU(4)/Sp(4), a fundamental
(UV-complete) description of the strong sector is possible, that is informed by
the lattice; iii) The lightest vector resonances occur in the 10-plet, 5-plet
and singlet of Sp(4). Misalignment leads to a 10-plet "parity-doubling"
cancelation in the $S$ parameter, and a suppressed 5-plet contribution; iv)
Higgs coupling deviations are typically of $\mathcal O(1\%)$; v) The 10-plet
isotriplet resonances decay dominantly to a massive technipion and a gauge
boson, or to technipion pairs, rather than to gauge boson or fermion pairs;
moreover, their couplings to fermions are small. Thus, the bounds on this setup
from conventional heavy-vector-triplet searches are weak. A supersymmetric
$U(1)_R$ symmetric realization is briefly described.


title: A Quantum Implementation Model for Artificial Neural Networks

abstract:
  The learning process for multi layered neural networks with many nodes makes
heavy demands on computational resources. In some neural network models, the
learning formulas, such as the Widrow-Hoff formula, do not change the
eigenvectors of the weight matrix while flatting the eigenvalues. In infinity,
this iterative formulas result in terms formed by the principal components of
the weight matrix: i.e., the eigenvectors corresponding to the non-zero
eigenvalues. In quantum computing, the phase estimation algorithm is known to
provide speed-ups over the conventional algorithms for the eigenvalue-related
problems. Combining the quantum amplitude amplification with the phase
estimation algorithm, a quantum implementation model for artificial neural
networks using the Widrow-Hoff learning rule is presented. The complexity of
the model is found to be linear in the size of the weight matrix. This provides
a quadratic improvement over the classical algorithms.


title: Matrix Norms in Data Streams: Faster, Multi-Pass and Row-Order

abstract:
  A central problem in data streams is to characterize which functions of an
underlying frequency vector can be approximated efficiently. Recently there has
been considerable effort in extending this problem to that of estimating
functions of a matrix that is presented as a data-stream. This setting
generalizes classical problems to the analogous ones for matrices. For example,
instead of estimating frequent-item counts, we now wish to estimate
"frequent-direction" counts. A related example is to estimate norms, which now
correspond to estimating a vector norm on the singular values of the matrix.
Despite recent efforts, the current understanding for such matrix problems is
considerably weaker than that for vector problems.
  We study a number of aspects of estimating matrix norms in a stream that have
not previously been considered: (1) multi-pass algorithms, (2) algorithms that
see the underlying matrix one row at a time, and (3) time-efficient algorithms.
Our multi-pass and row-order algorithms use less memory than what is provably
required in the single-pass and entrywise-update models, and thus give
separations between these models (in terms of memory). Moreover, all of our
algorithms are considerably faster than previous ones. We also prove a number
of lower bounds, and obtain for instance, a near-complete characterization of
the memory required of row-order algorithms for estimating Schatten $p$-norms
of sparse matrices.


title: Estimating yield-strain via deformation-recovery simulations

abstract:
  In computational materials science, predicting the yield strain of
crosslinked polymers remains a challenging task. A common approach is to
identify yield as the first critical point of stress-strain curves simulated by
molecular dynamics (MD). However, in such cases the underlying data can be
excessively noisy, making it difficult to extract meaningful results. In this
work, we propose an alternate method for identifying yield on the basis of
deformation-recovery simulations. Notably, the corresponding raw data (i.e.
residual strains) produce a sharper signal for yield via a transition in their
global behavior. We analyze this transition by non- linear regression of
computational data to a hyperbolic model. As part of this analysis, we also
propose uncertainty quantification techniques for assessing when and to what
extent the simulated data is informative of yield. Moreover, we show how the
method directly tests for yield via the onset of permanent deformation and
discuss recent experimental results, which compare favorably with our
predictions.


title: Analysis and optimization of weighted ensemble sampling

abstract:
  We give a mathematical framework for weighted ensemble (WE) sampling, a
binning and resampling technique for efficiently computing probabilities in
molecular dynamics. We prove that WE sampling is unbiased in a very general
setting that includes adaptive binning. We show that when WE is used for
stationary calculations in tandem with a coarse model, the coarse model can be
used to optimize the allocation of replicas in the bins.


title:
Microrheology of viscoelastic solutions studied by magnetic rotational
  spectroscopy

abstract:
  Magnetic rotational spectroscopy is based on the use of magnetic micron-size
wires for viscosity measurements. Submitted to a rotational magnetic field with
increasing frequency, the wires undergo a hydrodynamic instability between a
synchronous and an asynchronous regime. From a comparison between predictions
and experiments, the static shear viscosity and elastic modulus of wormlike
micellar solutions are here determined. The values agree with the determination
by cone-and-plate rheometry.


title:
Non-orthogonality and $\kappa$-dependence eccentricity of polarized
  electromagnetic waves in CPT-even Lorentz violation

abstract:
  We discuss the modified Maxwell action of a $K_{F}$-type Lorentz symmetry
breaking theory and present a solution of Maxwell equations derived in the
cases of linear and elliptically polarized electromagnetic waves in the vacuum
of CPT-even Lorentz violation. We show in this case the Lorentz violation has
the effect of changing the amplitude of one component of the magnetic field,
while leaving the electric field unchanged, leading to non-orthogonal
propagation of eletromagnetic fields and dependence of the eccentricity on
$\kappa$-term. Further, we exhibit numerically the consequences of this effect
in the cases of linear and elliptical polarization, in particular, the regimes
of non-orthogonality of the electromagnetic wave fields and the eccentricity of
the elliptical polarization of the magnetic field with dependence on the
$\kappa$-term.


title: On Faces of the set of Quantum Channels

abstract:
  A linear map $L$ from ${\mathbb C}^{n \times n}$ into ${\mathbb C}^{n \times
n}$ is called a quantum channel if it is completely positive and trace
preserving. The set ${\cal L}_n$ of all such quantum channels is known to be a
compact convex set. While the extreme points of ${\cal L}_n$ can be
characterized, not much is known about the structure of its higher dimensional
faces. Using the so called Choi matrix $Z(L)$ associated with the quantum
channel $L$, we compute the maximum dimension of a proper face of ${\cal L}_n$,
and in addition the possible dimensions of faces generated by $L$ when $rank \
Z(L)=2 $.


title: Equal angles of intersecting geodesics for every hyperbolic metric

abstract:
  We study the geometric properties of the terms of the Goldman bracket between
two free homotopy classes of oriented closed curves in a hyperbolic surface. We
provide an obstruction for the equality of two terms in the Goldman bracket,
namely if two terms in the Goldman bracket are equal to each other then for
every hyperbolic metric, the angles corresponding to the intersection points
are equal to each other. As a consequence, we obtain an alternative proof of a
theorem of Chas, i.e. if one of the free homotopy classes contains a simple
representative then the geometric intersection number and the number of terms
(counted with multiplicity) in the Goldman bracket are the same.


title: A triality Group of nonassociative algebras with involution

abstract:
  This paper is to study for local triality relations and ist global relations
That is, this is a generalization of automorhisms and derivations.


title:
\bf $\delta M$ Formalism: A New Approach to Cosmological Perturbation
  Theory in Anisotropic Inflation

abstract:
  We study the evolution of the metric perturbations in a Bianchi background in
the long-wavelength limit. By applying the gradient expansion to the equations
of motion we exhibit a generalized "Separate Universe" approach to the
cosmological perturbation theory. Having found this consistent separate
universe picture, we introduce the $\delta M $ formalism for calculating the
evolution of the linear tensor perturbations in anisotropic inflation models in
{\it almost} the same way that the so-called $\delta N$ formula is applied to
the super-horizon dynamics of the curvature perturbations. Similar to her twin
formula, $\delta N$, this new method can substantially reduce the amount of
calculations related to the evolution of tensor modes. However, it is not as
general as $\delta N$, it is a "perturbative" formula and solves the shear only
to linear order. In other words, it is restricted to weak shear limit.


title:
HCO+ Detection of Dust-Depleted Gas in the Inner Hole of the LkCa 15
  Pre-Transitional Disk

abstract:
  LkCa 15 is an extensively studied star in the Taurus region known for its
pre-transitional disk with a large inner cavity in dust continuum and normal
gas accretion rate. The most popular hypothesis to explain the LkCa 15 data
invokes one or more planets to carve out the inner cavity, while gas continues
to flow across the gap from the outer disk onto the central star. We present
spatially unresolved HCO+ J=4-3 observations of the LkCa 15 disk from the JCMT
and model the data with the ProDiMo code. We find that: (1) HCO+ line-wings are
clearly detected, certifying the presence of gas in the cavity within <50 AU of
the star. (2) Reproducing the observed line-wing flux requires both a
significant suppression of cavity dust (by a factor >10^4 compared to the ISM)
and a substantial increase in the gas scale-height within the cavity (H_0/R_0 ~
0.6). An ISM dust-to-gas ratio (d:g=10^-2) yields too little line-wing flux
regardless of the scale-height or cavity gas geometry, while a smaller
scale-height also under predicts the flux even with a reduced d:g. (3) The
cavity gas mass is consistent with the surface density profile of the outer
disk extended inwards to the sublimation radius (corresponding to mass M_d ~
0.03 M_sun), and masses lower by a factor >10 appear to be ruled out.


title:
Overlap of exact and Gross-Pitaevskii wavefunctions in Bose-Einstein
  condensates of dilute gases

abstract:
  It has been proven theoretically for bosons with two-body repulsive
interaction potentials in the dilute limit that the Gross-Pitaevskii equation
provides the exact energy and density per particle as does the basic
many-particle Schroedinger equation [Lieb and Seiringer, Phys. Rev. Lett. 88,
170409 (2002)]. Here, we investigate the overlap of the Gross-Pitaevskii and
exact ground state wavefunctions. It is found that this overlap is always
smaller than unity and may even vanish in spite of the fact that both
wavefunctions provide the same energy and density per particle. Consequences
are discussed.


title: Hierarchical Prisoner's Dilemma in Hierarchical Public-Goods Game

abstract:
  The dilemma in cooperation is one of the major concerns in game theory. In a
public-goods game, each individual pays a cost for cooperation, or to prevent
defection, and receives a reward from the collected cost in a group. Thus,
defection is beneficial for each individual, while cooperation is beneficial
for the group. Now, groups (say, countries) consisting of individual players
also play games. To study such a multi-level game, we introduce a hierarchical
public-goods (HPG) game in which two groups compete for finite resources by
utilizing costs collected from individuals in each group. Analyzing this HPG
game, we found a hierarchical prisoner's dilemma, in which groups choose the
defection policy (say, armaments) as a Nash strategy to optimize each group's
benefit, while cooperation optimizes the total benefit. On the other hand, for
each individual within a group, refusing to pay the cost (say, tax) is a Nash
strategy, which turns to be a cooperation policy for the group, thus leading to
a hierarchical dilemma. Here, the reward received by one group increases with
the population, as does the collected cost. In spite of this, we find that
there exists an optimal group size that maximizes its payoff. Furthermore, when
the population asymmetry between two groups is large, a smaller group will
choose a cooperation policy (say, disarmament) to avoid excessive response from
the larger group, which leads to the resolution of the prisoner's dilemma
between the groups. The relevance of the HPG game to policy selection in
society and the optimal size in human or animal groups are discussed
accordingly.


title:
The CALYMHA survey: Lya luminosity function and global escape fraction
  of Lya photons at z=2.23

abstract:
  We present the CAlibrating LYMan-$\alpha$ with H$\alpha$ (CALYMHA) pilot
survey and new results on Lyman-$\alpha$ (Lya) selected galaxies at z~2. We use
a custom-built Lya narrow-band filter at the Isaac Newton Telescope, designed
to provide a matched volume coverage to the z=2.23 Ha HiZELS survey. Here we
present the first results for the COSMOS and UDS fields. Our survey currently
reaches a 3$\sigma$ line flux limit of ~4x10$^{-17}$ erg/s/cm$^{2}$, and a Lya
luminosity limit of ~10$^{42.3}$ erg/s. We find 188 Lya emitters over
7.3x10$^5$ Mpc$^{3}$, but also find significant numbers of other line emitting
sources corresponding to HeII, CIII] and CIV emission lines. These sources are
important contaminants, and we carefully remove them, unlike most previous
studies. We find that the Lya luminosity function at z=2.23 is very well
described by a Schechter function up to L~10$^{43}$ erg/s with
L$^*=10^{42.59+-0.05}$ erg/s, $\phi^*=10^{-3.09+-0.08}$ Mpc$^{-3}$ and
$\alpha$=-1.75+-0.15. Above L~10$^{43}$ erg/s the Lya luminosity function
becomes power-law like, driven by X-ray AGN. We find that Lya-selected emitters
have a high escape fraction of 37+-7%, anti-correlated with Lya luminosity and
correlated with Lya equivalent width. Lya emitters have ubiquitous large (~40
kpc) Lya haloes, 2x larger than their Ha extents. By directly comparing our Lya
and Ha luminosity functions we find that the global/overall escape fraction of
Lya photons (within a 13 kpc radius) from the full population of star-forming
galaxies is 5.1+-0.2% at the peak of the star formation history. An extra
3.3+-0.3% of Lya photons likely still escape, but at larger radii.


title: A Super-Solar Metallicity For Stars With Hot Rocky Exoplanets

abstract:
  The host star metallicity provide a measure of the conditions in
protoplanetary disks at the time of planet formation. Using a sample of over
20,000 Kepler stars with spectroscopic metallicities from the LAMOST survey, we
explore how the exoplanet population depends on host star metallicity as a
function of orbital period and planet size. We find that exoplanets with
orbital periods less than 10 days are preferentially found around metal-rich
stars ([Fe/H]~ 0.15 +- 0.05 dex). The occurrence rates of these hot exoplanets
increases to ~30% for super-solar metallicity stars from ~10% for stars with a
sub-solar metallicity. Cooler exoplanets, that resides at longer orbital
periods and constitute the bulk of the exoplanet population with an occurrence
rate of >~ 90%, have host-star metallicities consistent with solar. At short
orbital periods, P<10 days, the difference in host star metallicity is largest
for hot rocky planets (<1.7 R_Earth), where the metallicity difference is
[Fe/H] =~ 0.25 +- 0.07 dex. The excess of hot rocky planets around metal-rich
stars implies they either share a formation mechanism with hot Jupiters, or
trace a planet trap at the protoplanetary disk inner edge which is
metallicity-dependent. We do not find statistically significant evidence for a
previously identified trend that small planets toward the habitable zone are
preferentially found around low-metallicity stars. Refuting or confirming this
trend requires a larger sample of spectroscopic metallicities.


title:
Stellar populations across the black hole mass - velocity dispersion
  relation

abstract:
  Coevolution between supermassive black holes (BHs) and their host galaxies is
universally adopted in models for galaxy formation. In the absence of feedback
from active galactic nuclei, simulated massive galaxies keep forming stars in
the local Universe. From an observational point of view, however, such
coevolution remains unclear. We present a stellar population analysis of
galaxies with direct BH mass measurements and the BH mass-{\sigma} relation as
a working framework. We find that over-massive BH galaxies, i.e., galaxies
lying above the best-fitting BH mass-{\sigma} line, tend to be older and more
{\alpha}-element enhanced than under-massive BH galaxies. The scatter in the BH
mass-{\sigma}-[{\alpha}/Fe] plane is significantly lower than in the standard
BH mass-{\sigma} relation. We interpret this trend as an imprint of active
galactic nucleus feedback on the star formation histories of massive galaxies.


title:
Quasiparticle interference of heavy fermions in resonant X-ray
  scattering

abstract:
  Resonant X-ray scattering (RXS) has recently become an increasingly important
tool for the study of ordering phenomena in correlated electron systems. Yet,
the interpretation of the RXS experiments remains theoretically challenging due
to the complexity of the RXS cross-section. Central to this debate is the
recent proposal that impurity-induced Friedel oscillations, akin to
quasiparticle interference signals observed with the scanning tunneling
microscope (STM), can lead to scattering peaks in the RXS experiments. The
possibility that quasiparticle properties can be probed in RXS measurements
opens up a new avenue to study the bulk band structure of materials with the
orbital and element selectivity provided by RXS. Here, we test these ideas by
combining RXS and STM measurements of the heavy fermion compound CeMIn$_5$ (M =
Co, Rh). Temperature and doping dependent RXS measurements at the Ce-M$_4$ edge
show a broad scattering enhancement that correlates with the appearance of
heavy f-electron bands in these compounds. The scattering enhancement is
consistent with the measured quasiparticle interference signal in the STM
measurements, indicating that quasiparticle interference can be probed through
the momentum distribution of RXS signals. Overall, our experiments demonstrate
new opportunities for studies of correlated electronic systems using the RXS
technique.


title:
Sensitivity to a Frequency-Dependent Circular Polarization in an
  Isotropic Stochastic Gravitational Wave Background

abstract:
  We calculate the sensitivity to a circular polarization of an isotropic
stochastic gravitational wave background (ISGWB) as a function of frequency for
ground- and space-based interferometers and observations of the cosmic
microwave background. The origin of a circularly polarized ISGWB may be due to
exotic primordial physics (i.e., parity violation in the early universe) and
may be strongly frequency dependent. We present calculations within a coherent
framework which clarifies the basic requirements for sensitivity to circular
polarization, in distinction from previous work which focused on each of these
techniques separately. We find that the addition of an interferometer with the
sensitivity of the Einstein Telescope in the southern hemisphere improves the
sensitivity of the ground-based network to circular polarization by about a
factor of two. The sensitivity curves presented in this paper make clear that
the wide range in frequencies of current and planned observations ($10^{-18}\
{\rm Hz} \lesssim f \lesssim 100\ {\rm Hz}$) will be critical to determining
the physics that underlies any positive detection of circular polarization in
the ISGWB. We also identify a desert in circular polarization sensitivity for
frequencies between $10^{-15}\ {\rm Hz} \lesssim f \lesssim 10^{-3}\ {\rm Hz}$,
given the inability for pulsar timing arrays and indirect-detection methods to
distinguish the gravitational wave polarization.


title: Gauged Lepton Flavour

abstract:
  The gauging of the lepton flavour group is considered in the Standard Model
context and in its extension with three right-handed neutrinos. The anomaly
cancellation conditions lead to a Seesaw mechanism as underlying dynamics for
all leptons; requiring in addition a phenomenologically viable setup leads to
Majorana masses for the neutral sector: the type I Seesaw Lagrangian in the
Standard Model case and the inverse Seesaw in the extended model. Within the
minimal extension of the scalar sector, the Yukawa couplings are promoted to
scalar fields in the bifundamental of the flavour group. The resulting
low-energy Yukawa couplings are proportional to inverse powers of the vacuum
expectation values of those scalars; the protection against flavour changing
neutral currents differs from that of Minimal Flavor Violation. In all cases,
the $\mu-\tau$ flavour sector exhibits rich and promising phenomenological
signals.


title: Mass estimators for flattened dispersion-supported galaxies

abstract:
  We investigate the reliability of mass estimators based on the observable
velocity dispersion and half-light radius $R_\mathrm{h}$ for
dispersion-supported galaxies. We show how to extend them to flattened systems
and provide simple formulae for the mass within an ellipsoid under the
assumption the dark matter density and the stellar density are stratified on
the same self-similar ellipsoids. We demonstrate explicitly that the spherical
mass estimators (Walker et al. 2009, Wolf et al. 2010) give accurate values for
the mass within the half-light ellipsoid, provided $R_\mathrm{h}$ is replaced
by its `circularized' analogue $R_\mathrm{h}\sqrt{1-\epsilon}$. We provide a
mathematical justification for this surprisingly simple and effective
workaround. It means, for example, that the mass-to-light ratios are valid not
just when the light and dark matter are spherically distributed, but also when
they are flattened on ellipsoids of the same constant shape.


title: Dimensional Reduction for D3-brane Moduli

abstract:
  Warped string compactifications are central to many attempts to stabilize
moduli and connect string theory with cosmology and particle phenomenology. We
present a first-principles derivation of the low-energy 4D effective theory
from dimensional reduction of a D3-brane in a warped Calabi-Yau
compactification of type IIB string theory with imaginary self-dual 3-form
flux, including effects of D3-brane motion beyond the probe approximation, and
find the metric on the moduli space of brane positions, the universal volume
modulus, and axions descending from the 4-form potential. As D3-branes may be
considered as carrying either electric or magnetic charges for the self-dual
5-form field strength, we present calculations in both duality frames. Our
results are consistent with, but extend significantly, earlier results on the
low-energy effective theory arising from D3-branes in string compactifications.


title:
Supergravity Backgrounds for Four-Dimensional Maximally Supersymmetric
  Yang-Mills

abstract:
  In this note, we describe supersymmetric backgrounds for the four-dimensional
maximally supersymmetric Yang-Mills theory. As an extension of the method of
Festuccia and Seiberg to sixteen supercharges in four dimensions, we utilize
the coupling of the gauge theory to maximally extended conformal supergravity.
Included among the fields of the conformal supergravity multiplet is the
complexified coupling parameter of the gauge theory; therefore, backgrounds
with spacetime varying coupling--such as appear in F-theory and Janus
configurations--are naturally included in this formalism. We demonstrate this
with a few examples from past literature.