title:
Classification of the sign of the critical Casimir force in two
  dimensional systems at asymptotically large separations

abstract:
  We classify the sign of the critical Casimir force between two finite objects
separated by a large distance in the two dimensional systems that can be
described by conformal field theory (CFT). In particular, we show that as far
as the smallest scaling dimension present in the spectrum of the system is
smaller than one, the sign of the force is independent of the shape of the
objects and can be determined by the elements of the modular $S$-matrix of the
CFT. The provided formula for the sign of the force indicates that the force is
always attractive for equal boundary conditions independent of the shape of the
objects. However, different boundary conditions can lead to attractive or
repulsive forces. Using the derived formula, we prove the known results
regarding the Ising model and the free bosons. As new examples, we give
detailed results regarding the Q=3-states Potts model and the compactified
bosons. In particular, for the latter model we show that Dirichlet boundary
condition does not always lead to an attractive force.


title:
Magnetoresistance and surface roughness study of electrodeposited
  Ni50Co50/Cu multilayers

abstract:
  Room-temperature transport properties (the zero-field resistivity, \rho 0,
and the GMR) were studied for ED Ni50Co50/Cu multilayers as a function of the
individual layer thicknesses and total multilayer thickness. The Cu deposition
potential was optimized in order to obtain the preset layer thicknesses. The
surface roughness development was studied by AFM, which revealed an exponential
roughening with total thickness. The Cu layer thickness strongly influenced the
roughness evolution. As expected, \rho 0 decreased with increasing Cu layer
thickness whereas it increased strongly for large total multilayer thicknesses
that could be ascribed to the observed deposit roughening. All multilayers with
Cu layer thicknesses above about 1.5 nm exhibited a GMR behavior with a maximum
GMR of about 5 %. The GMR decreased for total multilayer thicknesses above
about 300 nm due to the strong increase of \rho 0, the latter caused by the
enhanced roughness. The GMR data indicated the appearance of a current at angle
to plane type scattering due to the layer undulations. The thickness evolution
of the MR data was analyzed in detail after separating the ferromagnetic and
superparamagnetic GMR contributions. It could be established that ED Ni-Co/Cu
multilayers do not exhibit an oscillatory GMR behavior with spacer thickness.


title:
Low-power Spin Valve Logic using Spin-transfer Torque with Automotion of
  Domain Walls

abstract:
  A novel scheme for non-volatile digital computation is proposed using
spin-transfer torque (STT) and automotion of magnetic domain walls (DWs). The
basic computing element is composed of a lateral spin valve (SV) with two
ferromagnetic (FM) wires served as interconnects, where DW automotion is used
to propagate the information from one device to another. The non-reciprocity of
both device and interconnect is realized by sizing different contact areas at
the input and the output as well as enhancing the local damping mechanism. The
proposed logic is suitable for scaling due to a high energy barrier provided by
a long FM wire. Compared to the scheme based on non-local spin valves (NLSVs)
in the previous proposal, the devices can be operated at lower current density
due to utilizing all injected spins for local magnetization reversals, and thus
improve both energy efficiency and resistance to electromigration. This device
concept is justified by simulating a buffer, an inverter, and a 3-input
majority gate with comprehensive numerical simulations, including spin
transport through the FM/non-magnetic (NM) interfaces as well as the NM channel
and stochastic magnetization dynamics inside FM wires. In addition to digital
computing, the proposed framework can also be used as a transducer between DWs
and spin currents for higher wiring flexibility in the interconnect network.


title: Robust quantum optimizer with full connectivity

abstract:
  Quantum phenomena have the potential to speed up the solution of hard
optimization problems. For example quantum annealing, based on the quantum
tunneling effect, has recently been shown to scale exponentially better with
system size as compared with classical simulated annealing. However, current
realizations of quantum annealers with superconducting qubits face two major
challenges. First, the connectivity between the qubits is limited, excluding
many optimization problems from a direct implementation. Second, decoherence
degrades the success probability of the optimization. We address both of these
shortcomings and propose an architecture in which the qubits are robustly
encoded in continuous variable degrees of freedom. Remarkably, by leveraging
the phenomenon of flux quantization, all-to-all connectivity is obtained
without overhead. Furthermore, we demonstrate the robustness of this
architecture by simulating the optimal solution of a small instance of the
NP-hard and fully connected number partitioning problem in the presence of
dissipation.


title: Robotic Swarm Control from Spatio-Temporal Specifications

abstract:
  In this paper, we study the problem of controlling a two-dimensional robotic
swarm with the purpose of achieving high level and complex spatio-temporal
patterns. We use a rich spatio-temporal logic that is capable of describing a
wide range of time varying and complex spatial configurations, and develop a
method to encode such formal specifications as a set of mixed integer linear
constraints, which are incorporated into a mixed integer linear programming
problem. We plan trajectories for each individual robot such that the whole
swarm satisfies the spatio-temporal requirements, while optimizing total robot
movement and/or a metric that shows how strongly the swarm trajectory resembles
given spatio-temporal behaviors. An illustrative case study is included.


title: An Improved Point-Line Incidence Bound Over Arbitrary Fields

abstract:
  We prove a new upper bound for the number of incidences between points and
lines in a plane over an arbitrary field $\mathbb{F}$, a problem first
considered by Bourgain, Katz and Tao. Specifically, we show that $m$ points and
$n$ lines in $\mathbb{F}^2$, with $m^{7/8}<n<m^{8/7}$, determine at most
$O(m^{11/15}n^{11/15})$ incidences (where, if $\mathbb{F}$ has positive
characteristic $p$, we assume $m^{-2}n^{13}\ll p^{15}$). This improves on the
previous best known bound, due to Jones. To obtain our bound, we first prove an
optimal point-line incidence bound on Cartesian products, using a reduction to
a point-plane incidence bound of Rudnev. We then cover most of the point set
with Cartesian products, and we bound the incidences on each product
separately, using the bound just mentioned. We give several applications, to
sum-product-type problems, an expander problem of Bourgain, the distinct
distance problem and Beck's theorem.


title: Constraints on scattering amplitudes in multistate Landau-Zener theory

abstract:
  We derive a set of constraints, which we will call hierarchy constraints
(HCs), on scattering amplitudes of an arbitrary multistate Landau-Zener model
(MLZM). The presence of additional symmetries can transform such constraints
into nontrivial relations between elements of the transition probability
matrix. This observation can be used to derive complete solutions of some MLZMs
or, for models that cannot be solved completely, to reduce the number of
independent elements of the transition probability matrix.

categories: quant-ph cond-mat.mes-hall math-ph math.MP nlin.SI


title:
Global existence and asymptotic behavior of solutions to the Euler
  equations with time-dependent damping

abstract:
  We study the isentropic Euler equations with time-dependent damping, given by
$\frac{\mu}{(1+t)^\lambda}\rho u$. Here, $\lambda,\mu$ are two non-negative
constants to describe the decay rate of damping with respect to time. We will
investigate the global existence and asymptotic behavior of small data
solutions to the Euler equations when $0<\lambda<1,0<\mu$ in multi-dimensions
$n\geq 1$. The asymptotic behavior will coincide with the one that obtained by
many authors in the case $\lambda=0$. We will also show that the solution can
only decay polynomially in time while in the three dimensions, the vorticity
will decay exponentially fast.


title: Distributed Lagrangian Methods for Network Resource Allocation

abstract:
  Motivated by a variety of applications in control engineering and information
sciences, we study network resource allocation problems where the goal is to
optimally allocate a fixed amount of resource over a network of nodes. In these
problems, due to the large scale of the network and complicated
inter-connections between nodes, any solution must be implemented in parallel
and based only on local data resulting in a need for distributed algorithms. In
this paper, we propose a novel distributed Lagrangian method, which requires
only local computation and communication. Our focus is to understand the
performance of this algorithm on the underlying network topology. Specifically,
we obtain an upper bound on the rate of convergence of the algorithm as a
function of the size and the topology of the underlying network. The
effectiveness and applicability of the proposed method is demonstrated by its
use in solving the important economic dispatch problem in power systems,
specifically on the benchmark IEEE-14 and IEEE-118 bus systems.


title: No positive cone in a free product is regular

abstract:
  We show that there exists no left order on the free product of two
nontrivial, finitely generated, left-orderable groups such that the
corresponding positive cone is represented by a regular language. Since there
are orders on free groups of rank at least two with positive cone languages
that are context-free (in fact, 1-counter languages), our result provides a
bound on the language complexity of positive cones in free products that is the
best possible within the Chomsky hierarchy. It also provides a strengthening of
a result by Cristobal Rivas stating that the positive cone in a free product of
nontrivial, finitely generated, left-orderable groups cannot be finitely
generated as a semigroup.


title: Spinorial representation of submanifolds in metric Lie groups

abstract:
  In this paper we give a spinorial representation of submanifolds of any
dimension and codimension into Lie groups equipped with left invariant metrics.
As applications, we get a spinorial proof of the Fundamental Theorem for
submanifolds into Lie groups, we recover previously known representations of
submanifolds in $\mathbb{R}^n$ and in the 3-dimensional Lie groups $S^3$ and
$E(\kappa,\tau),$ and we get a new spinorial representation for surfaces in the
3-dimensional semi-direct products: this achieves the spinorial representations
of surfaces in the 3-dimensional homogeneous spaces. We finally indicate how to
recover a Weierstrass-type representation for CMC-surfaces in 3-dimensional
metric Lie groups recently given by Meeks, Mira, Perez and Ros.


title: Nested Words for Order-2 Pushdown Systems

abstract:
  We study linear time model checking of collapsible higher-order pushdown
systems (CPDS) of order 2 (manipulating stack of stacks) against MSO and PDL
(propositional dynamic logic with converse and loop) enhanced with push/pop
matching relations. To capture these linear time behaviours with matchings, we
propose order-2 nested words. These graphs consist of a word structure
augmented with two binary matching relations, one for each order of stack,
which relate a push with matching pops (or collapse) on the respective stack.
Due to the matching relations, satisfiability and model checking are
undecidable. Hence we propose an under-approximation, bounding the number of
times an order-1 push can be popped. With this under-approximation, which still
allows unbounded stack height, we get decidability for satisfiability and model
checking of both MSO and PDL. The problems are ExpTime-Complete for PDL.


title:
Relativistic Energies and Scattering Phase Shifts for the Fermionic
  Particles Scattered by Hyperbolical potential with the Pseudo (Spin) Symmetry

abstract:
  In this paper, we studied the approximate scattering state solutions of the
Dirac equation with the hyperbolical potential with pseudospin and spin
symmetries. Using a suitable short range approximation within the formalism of
functional analytical method, we obtained the spin-orbit quantum numbers
dependent scattering phase shifts for the spin and pseudospin symmetries. The
normalization constants, lower and upper radial spinor for the two symmetries
and the relativistic energy spectra were presented. Our results reveal that
both the symmetry constants (C_ps and C_s) and the spin-orbit quantum number
\k{appa} affect scattering phase shifts significantly.


title: Solitons in one-dimensional lattices with a flat band

abstract:
  We investigate the spectral properties of a quasi-one-dimensional lattice in
two possible dimerisation configurations. Both configurations are characterized
by the same lattice topology and the identical spectra containing a flat band
at zero energy. We find that one of the dimerised configuration has similar
symmetry to a one-dimensional chain proposed by Su-Schrieffer-Heeger for
studying solitons in conjugated polymers. Whereas, the other dimerised
configuration only shows non-trivial topological properties in the presence of
chiral-symmetry breaking adiabatic pumping.


title: Non-boost-invariant dissipative hydrodynamics

abstract:
  The one-dimensional non-boost-invariant evolution of the quark-gluon plasma,
presumably produced during the early stages of heavy-ion collisions, is
analyzed within the frameworks of viscous and anisotropic hydrodynamics. We
neglect transverse dynamics and assume homogeneous conditions in the transverse
plane but, differently from Bjorken expansion, we relax longitudinal boost
invariance in order to study the rapidity dependence of various hydrodynamical
observables. We compare the results obtained using several formulations of
second-order viscous hydrodynamics with a recent approach to anisotropic
hydrodynamics, which treats the large initial pressure anisotropy in a
non-perturbative fashion. The results obtained with second-order viscous
hydrodynamics depend on the particular choice of the second-order terms
included, which suggests that the latter should be included in the most
complete way. The results of anisotropic hydrodynamics and viscous
hydrodynamics agree for the central hot part of the system, however, they
differ at the edges where the approach of anisotropic hydrodynamics helps to
control the undesirable growth of viscous corrections observed in standard
frameworks.


title: The Return of the King: No-Scale ${\cal F}$-$SU(5)$

abstract:
  We revisit the viable parameter space in No-Scale ${\cal F}$-$SU(5)$,
examining the Grand Unified Theory within the context of the prevailing gluino
mass limits established by the LHC. The satisfaction of both the No-Scale
boundary condition and the experimentally measured Standard Model (SM) like
Higgs boson mass requires a lower limit on the gluino mass in the model space
of about 1.9 TeV, which maybe not coincidentally is the current LHC
supersymmetry search bound. This offers a plausible explanation as to why a
supersymmetry signal has thus far not been observed at the LHC. On the
contrary, since the vector-like flippon particles are relatively heavy due to
the strict condition that the supersymmetry breaking soft term $B_{\mu}$ must
vanish at the unification scale, we also cannot address the recently vanished
750 GeV diphoton resonance at the 13 TeV LHC. Therefore, No-Scale ${\cal
F}$-$SU(5)$ returns as a King after the spurious 750 GeV diphoton excess was
gone with the wind.


title: Near-Optimal (Euclidean) Metric Compression

abstract:
  The metric sketching problem is defined as follows. Given a metric on $n$
points, and $\epsilon>0$, we wish to produce a small size data structure
(sketch) that, given any pair of point indices, recovers the distance between
the points up to a $1+\epsilon$ distortion. In this paper we consider metrics
induced by $\ell_2$ and $\ell_1$ norms whose spread (the ratio of the diameter
to the closest pair distance) is bounded by $\Phi>0$. A well-known
dimensionality reduction theorem due to Johnson and Lindenstrauss yields a
sketch of size $O(\epsilon^{-2} \log (\Phi n) n\log n)$, i.e., $O(\epsilon^{-2}
\log (\Phi n) \log n)$ bits per point. We show that this bound is not optimal,
and can be substantially improved to $O(\epsilon^{-2}\log(1/\epsilon) \cdot
\log n + \log\log \Phi)$ bits per point. Furthermore, we show that our bound is
tight up to a factor of $\log(1/\epsilon)$.
  We also consider sketching of general metrics and provide a sketch of size
$O(n\log(1/\epsilon)+ \log\log \Phi)$ bits per point, which we show is optimal.


title: Gravitational radiation from a rotating magnetic dipole

abstract:
  The gravitational radiation emitted by a rotating magnetic dipole is
calculated. Formulas for the polarization amplitudes and the radiated power are
obtained in closed forms. A comparison is made with other sources of
gravitational and electromagnetic radiation, particularly neutron stars with
extremely powerful magnetic fields.


title: A Generalization of the {\L}o\'s-Tarski Preservation Theorem

abstract:
  In this dissertation, we present for each natural number $k$, semantic
characterizations of the $\exists^k \forall^*$ and $\forall^k \exists^*$ prefix
classes of first order logic sentences, over all structures finite and
infinite. This result, that we call the *generalized {\L}o\'s-Tarski theorem*,
abbreviated $\mathsf{GLT}(k)$, yields the classical {\L}o\'s-Tarski
preservation theorem when $k$ equals 0. It also provides new characterizations
of the $\Sigma^0_2$ and $\Pi^0_2$ prefix classes, that are finer than all
characterizations of these classes in the literature. Further, our semantic
notions are finitary in nature, in contrast to those contained in the
literature characterizations.
  In the context of finite structures, we formulate an abstract combinatorial
property of structures, that when satisfied by a class, ensures that
$\mathsf{GLT}(k)$ holds over the class. This property, that we call the
*Equivalent Bounded Substructure Property*, abbreviated $\mathsf{EBSP}$,
intuitively states that a large structure contains a small "logically similar"
substructure. It turns out that this simply stated property is enjoyed by a
variety of classes of interest in computer science: examples include words,
trees (unordered, ordered or ranked), nested words, graph classes of bounded
tree-depth/shrub-depth, and $m$-partite cographs. Further, $\mathsf{EBSP}$
remains preserved under various well-studied operations, such as
complementation, transpose, the line-graph operation, disjoint union, cartesian
and tensor products, etc. This enables constructing a wide spectrum of classes
that satisfy $\mathsf{EBSP}$, and hence $\mathsf{GLT}(k)$. Remarkably,
$\mathsf{EBSP}$ can be regarded as a finitary analogue of the classical
downward L\"owenheim-Skolem property.
  In summary, this dissertation provides new notions and results in both
contexts, that of all structures and that of finite structures.


title:
The scalar glueball operator, the a-theorem, and the onset of
  conformality

abstract:
  We show that the anomalous dimension $\gamma_G$ of the scalar glueball
operator contains information on the mechanism that leads to the onset of
conformality at the lower edge of the conformal window in a non-Abelian gauge
theory. In particular, it distinguishes whether the merging of an UV and an IR
fixed point -- the simplest mechanism associated to a conformal phase
transition and preconformal scaling -- does or does not occur. At the same
time, we shed light on new analogies between QCD and its supersymmetric
version. In SQCD, we derive an exact relation between $\gamma_G$ and the mass
anomalous dimension $\gamma_m$, and we prove that the SQCD exact beta function
is incompatible with merging as a consequence of the $a$-theorem; we also
derive the general conditions that the latter imposes on the existence of fixed
points, and prove the absence of an UV fixed point at nonzero coupling above
the conformal window of SQCD. Perhaps not surprisingly, we then show that an
exact relation between $\gamma_G$ and $\gamma_m$, fully analogous to SQCD,
holds for the massless Veneziano limit of large-N QCD. We argue, based on the
latter relation, the $a$-theorem, perturbation theory and physical arguments,
that the incompatibility with merging may extend to QCD.


title:
Corrigendum: "On the dynamics of the Meissner effect", arXiv:1508.03307,
  Phys. Scr. 91, 035801 (2016)

abstract:
  The paper erroneously assumed that the normal carriers giving rise to the
backflow could be either electrons or holes.


title: A Dynamical Boundary for Anti-de Sitter Space

abstract:
  We argue that a natural boundary condition for gravity in asymptotically AdS
spaces is to hold the {\em renormalized} boundary stress tensor density fixed,
instead of the boundary metric. This leads to a well-defined variational
problem, as well as new counter-terms and a finite on-shell action. We
elaborate this in various (even and odd) dimensions in the language of
holographic renormalization. Even though the {\em form} of the new renormalized
action is distinct from the standard one, once the cut-off is taken to
infinity, their {\em values} on classical solutions coincide when the trace
anomaly vanishes. For AdS$_4$, we compute the ADM form of this renormalized
action and show in detail how the correct thermodynamics of Kerr-AdS black
holes emerge. We comment on the possibility of a consistent quantization with
our boundary conditions when the boundary is dynamical, and make a connection
to the results of Compere and Marolf. The difference between our approach and
microcanonical-like ensembles in standard AdS/CFT is emphasized.


title: Anomalous Dynamical Behavior of Freestanding Graphene Membranes

abstract:
  We report subnanometer, high-bandwidth measurements of the out-of-plane
(vertical) motion of atoms in freestanding graphene using scanning tunneling
microscopy. By tracking the vertical position over a long time period, a
1000-fold increase in the ability to measure space-time dynamics of atomically
thin membranes is achieved over the current state-of-the-art imaging
technologies. We observe that the vertical motion of a graphene membrane
exhibits rare long-scale excursions characterized by both anomalous
mean-squared displacements and Cauchy-Lorentz power law jump distributions.


title: Color-Based Coding Unit Level Adaptive Quantization for HEVC

abstract:
  HEVC HM 16 includes a Coding Unit (CU) level perceptual quantization
technique named AdaptiveQP. AdaptiveQP adjusts the Quantization Parameter (QP)
at the CU level based on the spatial activity of samples in the four
constituent NxN sub-blocks of the luma Coding Block (CB), which is contained
within a 2Nx2N CU. In this paper, we propose C-BAQ, which, in contrast to
AdaptiveQP, adjusts the CU level QP according to the spatial activity of
samples in the four constituent NxN sub-blocks of both the luma and chroma CBs.
By computing the sum of luma, chroma Cb and chroma Cr spatial activity in a CU,
a richer reflection of spatial activity in the CU is attained. Therefore, a
more appropriate CU level QP can be selected, thus leading to important
improvements in terms of coding efficiency. We evaluate the proposed technique
in HEVC HM 16.7 using 4:4:4, 4:2:2 and 4:2:0 YCbCr sequences. Both subjective
and objective evaluations are undertaken during which we compare C-BAQ with
AdaptiveQP. The objective evaluation reveals that C-BAQ attains a maximum
BD-Rate reduction of 15.9% (Y), 13.1% (Cr) and 16.1% (Cb) in addition to a
maximum decoding time reduction of 11.0%.


title: Floquet Topological Order in Interacting Systems of Bosons and Fermions

abstract:
  Periodically driven noninteracting systems may exhibit anomalous chiral edge
modes, despite hosting bands with trivial topology. We find that these drives
have surprising many-body analogs, corresponding to class A, which exhibit
anomalous charge and information transport at the boundary. Drives of this form
are applicable to generic systems of bosons, fermions, and spins, and may be
characterized by the anomalous unitary operator that acts at the edge of an
open system. We find that these operators are robust to all local perturbations
and may be classified by a pair of coprime integers. This defines a notion of
dynamical topological order that may be applied to general time-dependent
systems, including many-body localized phases or time crystals.


title:
Bayesian Mass Estimates of the Milky Way: including measurement
  uncertainties with hierarchical Bayes

abstract:
  We present a hierarchical Bayesian method for estimating the total mass and
mass profile of the Milky Way Galaxy. The new hierarchical Bayesian approach
further improves the framework presented by Eadie, Harris, & Widrow (2015) and
Eadie & Harris (2016) and builds upon the preliminary reports by Eadie et al
(2015a,c). The method uses a distribution function $f(\mathcal{E},L)$ to model
the galaxy and kinematic data from satellite objects such as globular clusters
(GCs) to trace the Galaxy's gravitational potential. A major advantage of the
method is that it not only includes complete and incomplete data simultaneously
in the analysis, but also incorporates measurement uncertainties in a coherent
and meaningful way. We first test the hierarchical Bayesian framework, which
includes measurement uncertainties, using the same data and power-law model
assumed in Eadie & Harris (2016), and find the results are similar but more
strongly constrained. Next, we take advantage of the new statistical framework
and incorporate all possible GC data, finding a cumulative mass profile with
Bayesian credible regions. This profile implies a mass within $125$kpc of
$4.8\times10^{11}M_{\odot}$ with a 95\% Bayesian credible region of
$(4.0-5.8)\times10^{11}M_{\odot}$. Our results also provide estimates of the
true specific energies of all the GCs. By comparing these estimated energies to
the measured energies of GCs with complete velocity measurements, we observe
that (the few) remote tracers with complete measurements may play a large role
in determining a total mass estimate of the Galaxy. Thus, our study stresses
the need for more remote tracers with complete velocity measurements.


title: Disorder-driven topological phase transition in Bi2Se3 films

abstract:
  Topological insulators (TI) are a phase of matter that host unusual metallic
states on their surfaces. Unlike the states that exist on the surface of
conventional materials, these so-called topological surfaces states (TSS) are
protected against disorder-related localization effects by time reversal
symmetry through strong spin-orbit coupling. By combining transport
measurements, angle-resolved photo-emission spectroscopy and scanning tunneling
microscopy, we show that there exists a critical level of disorder beyond which
the TI Bi2Se3 loses its ability to protect the metallic TSS and transitions to
a fully insulating state. The absence of the metallic surface channels dictates
that there is a change in topological character, implying that disorder can
lead to a topological phase transition even without breaking the time reversal
symmetry. This observation challenges the conventional notion of
topologically-protected surface states, and will provoke new studies as to the
fundamental nature of topological phase of matter in the presence of disorder.


title: The Parallel-Repeated Magic Square Game is Rigid

abstract:
  We show that the $n$-round parallel repetition of the Magic Square game of
Mermin and Peres is rigid, in the sense that for any entangled strategy
succeeding with probability $1 -\varepsilon$, the players' shared state is
$O(\mathrm{poly}(n\varepsilon))$-close to $2n$ EPR pairs under a local
isometry. Furthermore, we show that, under local isometry, the players'
measurements in said entangled strategy must be
$O(\mathrm{poly}(n\varepsilon))$ close to the "ideal" strategy when acting on
the shared state.


title:
The GALEX Time Domain Survey. II. Wavelength-Dependent Variability of
  Active Galactic Nuclei in the Pan-STARRS1 Medium Deep Survey

abstract:
  We analyze the wavelength-dependent variability of a sample of
spectroscopically confirmed active galactic nuclei (AGN) selected from near-UV
($NUV$) variable sources in the GALEX Time Domain Survey that have a large
amplitude of optical variability (difference-flux S/N $>$ 3) in the Pan-STARRS1
Medium Deep Survey (PS1 MDS). By matching GALEX and PS1 epochs in 5 bands
($NUV$, $g_{P1}$, $r_{P1}$, $i_{P1}$, $z_{P1}$) in time, and taking their flux
difference, we create co-temporal difference-flux spectral energy distributions
($\Delta f$SEDs) using two chosen epochs for each of the 23 objects in our
sample on timescales of about a year.
  We confirm the "bluer-when-brighter" trend reported in previous studies, and
measure a median spectral index of the $\Delta f$SEDs of $\alpha_{\lambda}$ =
2.1 that is consistent with an accretion disk spectrum. We further fit the
$\Delta f$SEDs of each source with a standard accretion disk model in which the
accretion rate changes from one epoch to the other. In our sample, 17 out of 23
($\sim$74 %) sources are well described by this variable accretion-rate disk
model, with a median average characteristic disk temperature $\bar{T}^*$ of
$1.2\times 10^5$~K that is consistent with the temperatures expected given the
distribution of accretion rates and black hole masses inferred for the sample.
Our analysis also shows that the variable accretion rate model is a better fit
to the $\Delta f$SEDs than a simple power law.


title:
The Properties of the Circumgalactic Medium in Red and Blue Galaxies:
  Results from the COS-GASS+COS-Halos Surveys

abstract:
  We use the combined data from the COS-GASS and COS-Halos surveys to
characterize the Circum-Galactic Medium (CGM) surrounding typical low-redshift
galaxies in the mass range $\rm~M_*\sim~10^{9.5-11.5}~M_{\odot} $, and over a
range of impact parameters extending to just beyond the halo virial radius
($\rm~R_{vir}$). We find the radial scale length of the distributions of the
equivalent widths of the Lyman~$\alpha$ and Si III absorbers to be 0.9 and 0.4
$\rm~R_{vir}$, respectively. The radial distribution of equivalent widths is
relatively uniform for the blue galaxies, but highly patchy (low covering
fraction) for the red galaxies. We also find that the Lyman~$\alpha$ and Si III
equivalent widths show significant positive correlations with the specific
star-formation rate (sSFR) of the galaxy. We find a surprising lack of
correlations between the halo mass (virial velocity) and either the velocity
dispersions or velocity offsets of the Lyman~$\alpha$ lines. The ratio of the
velocity offset to the velocity dispersion for the Lyman~$\alpha$ absorbers has
a mean value of $\sim$ 4, suggesting that a given the line-of-sight is
intersecting a dynamically coherent structure in the CGM rather than a sea of
orbiting clouds. The kinematic properties of the CGM are similar in the blue
and red galaxies, although we find that a significantly larger fraction of the
blue galaxies have large Lyman~$\alpha$ velocity offsets (>200 km s$^{-1}$). We
show that - if the CGM clouds represent future fuel for star-formation - our
new results could imply a large drop in the specific star-formation rate across
the galaxy mass-range we probe.


title: The Galactic fountain as an origin for the Smith Cloud

abstract:
  The recent discovery of an enriched metallicity for the Smith high-velocity
HI cloud (SC) lends support to a Galactic origin for this system. We use a
dynamical model of the galactic fountain to reproduce the observed properties
of the SC. In our model, fountain clouds are ejected from the region of the
disc spiral arms and move through the halo interacting with a pre-existing hot
corona. We find that a simple model where cold gas outflows vertically from the
Perseus spiral arm reproduces the kinematics and the distance of the SC, but is
in disagreement with the cloud's cometary morphology, if this is produced by
ram-pressure stripping by the ambient gas. To explain the cloud morphology we
explore two scenarios: a) the outflow is inclined with respect to the vertical
direction; b) the cloud is entrained by a fast wind that escapes an underlying
superbubble. Solutions in agreement with all observational constraints can be
found for both cases, the former requires outflow angles >40 deg while the
latter requires >1000 km/s winds. All scenarios predict that the SC is in the
ascending phase of its trajectory and have large - but not implausible - energy
requirements.


title: Exclusive Weak Radiative Higgs Decays in the Standard Model and Beyond

abstract:
  We perform a detailed study of the exclusive Higgs decays $h\to MZ$ and $h\to
MW$, where $M$ is a pseudoscalar or vector meson, using the QCD factorization
approach. We allow for the presence of new-physics effects in the form of
modified Higgs couplings to gauge bosons and fermions, including the
possibility of flavor-changing Higgs couplings. We show that the decays $h\to
VZ$ exhibit a strong sensitivity to the effective CP-even and CP-odd $h\gamma
Z$ couplings. When combined with a measurement of the $h\to\gamma Z$ decay
rate, this can be used to extract these couplings up to a sign ambiguity in the
CP-odd coefficient. Some of the $h\to MW$ decay modes can be used to probe for
flavor-violating Higgs couplings involving the top quark.


title:
Cooling phonons with phonons: acoustic reservoir-engineering with
  silicon-vacancy centers in diamond

abstract:
  We study a setup where a single negatively-charged silicon-vacancy center in
diamond is magnetically coupled to a low-frequency mechanical bending mode and
via strain to the high-frequency phonon continuum of a semi-clamped diamond
beam. We show that under appropriate microwave driving conditions, this setup
can be used to induce a laser cooling like effect for the low-frequency
mechanical vibrations, where the high-frequency longitudinal compression modes
of the beam serve as an intrinsic low-temperature reservoir. We evaluate the
experimental conditions under which cooling close to the quantum ground state
can be achieved and describe an extended scheme for the preparation of a
stationary entangled state between two mechanical modes. By relying on
intrinsic properties of the mechanical beam only, this approach offers an
interesting alternative for quantum manipulation schemes of mechanical systems,
where otherwise efficient optomechanical interactions are not available.


title:
Anomalous Triple Gauge Couplings in the Effective Field Theory Approach
  at the LHC

abstract:
  We discuss how to perform consistent extractions of anomalous triple gauge
couplings (aTGC) from electroweak boson pair production at the LHC in the
Standard Model Effective Field Theory (SMEFT). After recasting recent ATLAS and
CMS searches in $pp\to WZ (WW) \to \ell' \nu \ell^+\ell^- (\nu_{\ell})$
channels, we find that: (a) working consistently at order $\Lambda^{-2}$ in the
SMEFT expansion the existing aTGC bounds from Higgs and LEP-2 data are not
improved, (b) the strong limits quoted by the experimental collaboration are
due to the partial $\Lambda^{-4}$ corrections (dimension-6 squared
contributions). Using helicity selection rule arguments we are able to explain
the suppression in some of the interference terms, and discuss conditions on
New Physics (NP) models that can benefit from such LHC analyses. Furthermore,
standard analyses assume implicitly a quite large NP scale, an assumption that
can be relaxed by imposing cuts on the underlying scale of the process
($\sqrt{\hat{s}}$). In practice, we find almost no correlation between
$\sqrt{\hat{s}}$ and the experimentally accessible quantities, which
complicates the SMEFT interpretation. Nevertheless, we provide a method to set
(conservative) aTGC bounds in this situation, and recast the present searches
accordingly. Finally, we introduce a simple NP model for aTGC to compare the
bounds obtained directly in the model with those from the SMEFT analysis.


title:
Fermion-induced quantum critical points in three-dimensional Weyl
  semimetals

abstract:
  Fermion-induced quantum critical points (FIQCPs) were recently discovered at
the putatively first-order transitions between two-dimensional (2D) Dirac
semimetals and the Kekule valence bond solids on the honeycomb lattice by
sign-free quantum Monte Carlo simulations [Nature Communications 8, 314,
(2017)]. Here, we investigate possible FIQCP in 3D topological Weyl semimetals
at a $Z_3$ symmetry-breaking transition that is putatively first-order
according to the Landau criterion. We construct a lattice model featuring 3D
double-Weyl fermions (monopole charges $\pm$2) and we show that $Z_3$
nodal-nematic transitions occur under finite Hubbard interaction. Furthermore,
using renormalization-group analysis, we identify such a transition as a
genuine FIQCP where the cubic terms are irrelevant and an enlarged U(1)
symmetry emerges at low energy. We further discuss quantum critical behaviors
and experimental signatures of such FIQCPs in 3D double-Weyl semimetals.


title:
Second quantization of Leinaas-Myrheim anyons in one dimension and their
  relation to the Lieb-Liniger model

abstract:
  In one spatial dimension, anyons in the original description of Leinaas and
Myrheim are formally equivalent to locally interacting bosons described by the
Lieb-Liniger model. This admits an interesting reinterpretation of interacting
bosons in the context of anyons. We elaborate on this parallel, particularly
including the many-body bound states from the attractive Lieb-Liniger model. In
the anyonic context these bound states are created purely by
quantum-statistical attraction and coined quantum-statistical condensate, which
is more robust than the Bose-Einstein condensate. We introduce the second
quantization formalism for the present anyons and construct the generalized
Jordan-Wigner transformation that connects them to the bosons of the
Lieb-Liniger model.


title: TGAS Error Renormalization from the RR Lyrae Period-Luminosity Relation

abstract:
  The Gaia team has applied a renormalization to their internally-derived
parallax errors $\sigma_{\rm int}(\pi)$ $$ \sigma_{tgas}(\pi) =
\sqrt{[A\sigma_{int}(\pi)]^2 + \sigma_0^2}; \ \ \ \ (A,\sigma_0) = (1.4,0.20\
\rm mas) $$ based on comparison to Hipparcos astrometry. We use a completely
independent method based on the RR Lyrae $K$-band period-luminosity relation to
derive a substantially different result, with smaller ultimate errors $$
(A,\sigma_0) = (1.1,0.12\ \rm mas) \ \ \ \ (this\ paper). $$ We argue that our
estimate is likely to be more accurate and therefore that the reported TGAS
parallax errors should be reduced according to the prescription: $$
\sigma_{true}(\pi) = \sqrt{(0.79\sigma_{tgas}(\pi))^2 - (0.10\ \rm mas)^2}. $$


title:
The Molecular Wind in the Nearest Seyfert Galaxy Circinus Revealed by
  ALMA

abstract:
  We present ALMA observations of the inner 1' (1.2 kpc) of the Circinus
galaxy, the nearest Seyfert. We target CO (1-0) in the region associated with a
well-known multiphase outflow driven by the central active galactic nucleus
(AGN). While the geometry of Circinus and its outflow make disentangling the
latter difficult, we see indications of outflowing molecular gas at velocities
consistent with the ionized outflow. We constrain the mass of the outflowing
molecular gas to be 1.5e5 -5.1e6 solar masses, yielding a molecular outflow
rate of 0.35-12.3 solar masses per year. The values within this range are
comparable to the star formation rate in Circinus, indicating that the outflow
indeed regulates star formation to some degree. The molecular outflow in
Circinus is considerably lower in mass and energetics than previously-studied
AGN-driven outflows, especially given its high ratio of AGN luminosity to
bolometric luminosity. The molecular outflow in Circinus is, however,
consistent with some trends put forth in Cicone et al. (2014), including a
linear relation between kinetic power and AGN luminosity, as well as its
momentum rate vs. bolometric luminosity (although the latter places Circinus
among the starburst galaxies in that sample). We detect additional molecular
species including CN and C17O.


title: Deep inelastic scattering on ultracold gases

abstract:
  We discuss Bragg scattering on both Bose and Fermi gases with strong
short-range interactions in the deep inelastic regime of large wave vector
transfer $q$, where the dynamic structure factor is dominated by a resonance
near the free-particle energy $\hbar\omega=\varepsilon_{\bf q}=\hbar^2q^2/2m$.
Using a systematic short-distance expansion, the structure factor at high
momentum is shown to exhibit a nontrivial dependence on frequency characterized
by two separate scaling regimes. First, for frequencies that differ from the
single-particle energy by terms of order ${\cal O}(q)$ (i.e., small deviations
compared to the single-particle energy), the dynamic structure factor is
described by the impulse approximation of Hohenberg and Platzman. Second,
deviations of order ${\cal O}(q^2)$ (i.e., of the same order or larger than the
single-particle energy) are described by the operator product expansion, with a
universal crossover connecting both regimes. The scaling is consistent with a
number of sum rules in the large momentum limit. Furthermore, we derive an
exact expression for the shift and width of the single-particle peak at large
momentum due to interactions, thus extending a result by Beliaev [JETP 7, 299
(1958)] for the low-density Bose gas to arbitrary values of the scattering
length $a$. The shift exhibits a maximum around $qa \simeq 1$, which is
connected with a maximum in the static structure factor due to strong
short-range correlations. For Bose gases with moderate interaction strengths,
the theoretically predicted shift is consistent with the value observed by Papp
et al. [Phys. Rev. Lett. 101, 135301 (2008)]. Finally, we develop a
diagrammatic theory for the dynamic structure factor which accounts for the
correlations beyond Bogoliubov theory and which covers the full range of
momenta and frequencies, showing the correct asymptotic scaling at large
momentum.


title: Asymptotic Symmetries in de Sitter and Inflationary Spacetimes

abstract:
  Soft gravitons produced by the expansion of de Sitter can be viewed as the
Nambu-Goldstone bosons of spontaneously broken asymptotic symmetries of the de
Sitter spacetime. We explicitly construct the associated charges, and show that
acting with the charges on the vacuum creates a new state equivalent to a
change in the local coordinates induced by the soft graviton. While the effect
remains unobservable within the domain of a single observer where the symmetry
is unbroken, this change is physical when comparing different asymptotic
observers, or between a transformed and un-transformed initial state,
consistent with the scale-dependent statistical anisotropies previously derived
using semiclassical relations. We then compute the overlap, $\langle0|
0'\rangle$, between the unperturbed de Sitter vacuum $|0\rangle$, and the state
$| 0'\rangle$ obtained by acting $\mathcal{N}$ times with the charge. We show
that when $\mathcal{N}\to M_p^2/H^2$ this overlap receives order one
corrections and $\langle0| 0'\rangle\to 0$, which corresponds to an infrared
perturbative breakdown after a time $t_{dS} \sim M_p^2/H^3$ has elapsed,
consistent with earlier arguments in the literature arguing for a perturbative
breakdown on this timescale. We also discuss the generalization to inflation,
and rederive the 3-point and one-loop consistency relations.


title:
Shadows of our Former Companions: How the Single-Degenerate Binary Type
  Ia Supernova Scenario Affects Remnants

abstract:
  Here we present three-dimensional high resolution simulations of Type Ia
supernova in the presence of a non-degenerate companion. We find that the
presence of a nearby companion leaves a long-lived hole in the supernova
ejecta. In particular, we aim to study the long term evolution of this hole as
the supernova ejecta interacts with the surrounding interstellar medium. Using
estimates for the x-ray emission, we find that the hole generated by the
companion remains for many centuries after the interaction between the ejecta
and the interstellar medium. We also show that the hole is discernible over a
wide range of viewing angles and companion masses.


title: A small weak scale from a small cosmological constant

abstract:
  We propose a framework in which Weinberg's anthropic explanation of the
cosmological constant problem also solves the hierarchy problem. The weak scale
is selected by chiral dynamics that controls the stabilization of an extra
dimension. When the Higgs vacuum expectation value is close to a fermion mass
scale, the radius of an extra dimension becomes large, and develops an enhanced
number of vacua available to scan the cosmological constant down to its
observed value. At low energies, the radion necessarily appears as an
unnaturally light scalar, in a range of masses and couplings accessible to
fifth-force searches as well as scalar dark matter searches with atomic clocks
and gravitational-wave detectors. The fermion sector that controls the size of
the extra dimension consists of a pair of electroweak doublets and several
singlets. These leptons satisfy approximate mass relations related to the weak
scale and are accessible to the LHC and future colliders.


title:
Cosmic ray heating in cool core clusters - I. Diversity of steady state
  solutions

abstract:
  The absence of large cooling flows in cool core clusters appears to require
self-regulated energy feedback by active galactic nuclei (AGNs) but the exact
heating mechanism has not yet been identified. Here, we analyse whether a
combination of cosmic ray (CR) heating and thermal conduction can offset
radiative cooling. To this end, we compile a large sample of 39 cool core
clusters and determine steady state solutions of the hydrodynamic equations
that are coupled to the CR energy equation. We find solutions that match the
observed density and temperature profiles for all our clusters well. Radiative
cooling is balanced by CR heating in the cluster centres and by thermal
conduction on larger scales, thus demonstrating the relevance of both heating
mechanisms. Our mass deposition rates vary by three orders of magnitude and are
linearly correlated to the observed star formation rates. Clusters with large
mass deposition rates show larger cooling radii and require a larger radial
extent of the CR injection function. Interestingly, our sample shows a
continuous sequence in cooling properties: clusters hosting radio mini halos
are characterised by the largest cooling radii, star formation and mass
deposition rates in our sample and thus signal the presence of a higher cooling
activity. The steady state solutions support the structural differences between
clusters hosting a radio mini halo and those that do not.


title:
Cosmic ray heating in cool core clusters - II. Self-regulation cycle and
  non-thermal emission

abstract:
  Self-regulated feedback by active galactic nuclei (AGNs) appears to be
critical in balancing radiative cooling of the low-entropy gas at the centres
of galaxy clusters and in regulating star formation in central galaxies. In a
companion paper, we found steady-state solutions of the hydrodynamic equations
that are coupled to the CR energy equation for a large cluster sample. In those
solutions, radiative cooling in the central region is balanced by streaming CRs
through the generation and dissipation of resonantly generated Alfv{\'e}n waves
and by thermal conduction at large radii. Here we demonstrate that the
predicted non-thermal emission resulting from hadronic CR interactions in the
intra-cluster medium exceeds observational radio (and gamma-ray) data in a
subsample of clusters that host radio mini halos (RMHs). In contrast, the
predicted non-thermal emission is well below observational data in cooling
galaxy clusters without RMHs. These are characterised by exceptionally large
AGN radio fluxes, indicating high CR yields and associated CR heating rates. We
suggest a self-regulation cycle of AGN feedback in which non-RMH clusters are
heated by streaming CRs homogeneously throughout the central cooling region. We
predict {\em radio micro halos} surrounding the AGNs of these CR-heated
clusters in which the primary emission may predominate the hadronically
generated emission. Once the CR population has streamed sufficiently far and
lost enough energy, the cooling rate increases, which explains the increased
star formation rates in clusters hosting RMHs. Those could be powered
hadronically by CRs that have previously heated the cluster core.


title: Automated Visual Fin Identification of Individual Great White Sharks

abstract:
  This paper discusses the automated visual identification of individual great
white sharks from dorsal fin imagery. We propose a computer vision photo ID
system and report recognition results over a database of thousands of
unconstrained fin images. To the best of our knowledge this line of work
establishes the first fully automated contour-based visual ID system in the
field of animal biometrics. The approach put forward appreciates shark fins as
textureless, flexible and partially occluded objects with an individually
characteristic shape. In order to recover animal identities from an image we
first introduce an open contour stroke model, which extends multi-scale region
segmentation to achieve robust fin detection. Secondly, we show that
combinatorial, scale-space selective fingerprinting can successfully encode fin
individuality. We then measure the species-specific distribution of visual
individuality along the fin contour via an embedding into a global `fin space'.
Exploiting this domain, we finally propose a non-linear model for individual
animal recognition and combine all approaches into a fine-grained
multi-instance framework. We provide a system evaluation, compare results to
prior work, and report performance and properties in detail.


title: The Interior of Saturn

abstract:
  We review our current understanding of the interior structure and thermal
evolution of Saturn, with a focus on recent results in the Cassini era. There
has been important progress in understanding physical inputs, including
equations of state of planetary materials and their mixtures, physical
parameters like the gravity field and rotation rate, and constraints on
Saturnian free oscillations. At the same time, new methods of calculation,
including work on the gravity field of rotating fluid bodies, and the role of
interior composition gradients, should help to better constrain the state of
Saturn's interior, now and earlier in its history. However, a better
appreciation of modeling uncertainties and degeneracies, along with a greater
exploration of modeling phase space, still leave great uncertainties in our
understanding of Saturn's interior. Further analysis of Cassini data sets, as
well as precise gravity field measurements from the Cassini Grand Finale
orbits, will further revolutionize our understanding of Saturn's interior over
the next few years.


title:
Exact distributions of cover times for $N$ independent random walkers in
  one dimension

abstract:
  We study the probability density function (PDF) of the cover time $t_c$ of a
finite interval of size $L$, by $N$ independent one-dimensional Brownian
motions, each with diffusion constant $D$. The cover time $t_c$ is the minimum
time needed such that each point of the entire interval is visited by at least
one of the $N$ walkers. We derive exact results for the full PDF of $t_c$ for
arbitrary $N \geq 1$, for both reflecting and periodic boundary conditions. The
PDFs depend explicitly on $N$ and on the boundary conditions. In the limit of
large $N$, we show that $t_c$ approaches its average value $\langle t_c \rangle
\approx L^2/(16\, D \, \ln N)$, with fluctuations vanishing as $1/(\ln N)^2$.
We also compute the centered and scaled limiting distributions for large $N$
for both boundary conditions and show that they are given by nontrivial
$N$-independent scaling functions.


title:
Probing nonstandard neutrino cosmology with terrestrial neutrino
  experiments

abstract:
  Neutrino masses and the number of light neutrino species can be tested in a
variety of laboratory experiments and also can be constrained by particle
astrophysics and precision cosmology. A conflict between these various results
could be an indication of new physics in the neutrino sector. In this paper we
explore the possibility for reconciliation of otherwise discrepant results in a
simple model containing a light scalar field which produces Mass Varying
Neutrinos (MaVaNs). We extend previous work on MaVaNs to consider issues of
neutrino clumping, the effects of additional contributions to neutrino mass,
and reconciliation of eV mass sterile neutrinos with cosmology.


title: Temporal Map Labeling: A New Unified Framework with Experiments

abstract:
  The increased availability of interactive maps on the Internet and on
personal mobile devices has created new challenges in computational cartography
and, in particular, for label placement in maps. Operations like rotation,
zoom, and translation dynamically change the map over time and make a
consistent adaptation of the map labeling necessary.
  In this paper, we consider map labeling for the case that a map undergoes a
sequence of operations over a specified time span. We unify and generalize
several preceding models for dynamic map labeling into one versatile and
flexible model. In contrast to previous research, we completely abstract from
the particular operations (e.g., zoom, rotation, etc.) and express the labeling
problem as a set of time intervals representing the labels' presences,
activities, and conflicts. The model's strength is manifested in its simplicity
and broad range of applications. In particular, it supports label selection
both for map features with fixed position as well as for moving entities (e.g.,
for tracking vehicles in logistics or air traffic control).
  Through extensive experiments on OpenStreetMap data, we evaluate our model
using algorithms of varying complexity as a case study for navigation systems.
Our experiments show that even simple (and thus, fast) algorithms achieve
near-optimal solutions in our model with respect to an intuitive objective
function.


title:
Multiwavelength monitoring and X-ray brightening of Be X-ray binary PSR
  J2032+4127/MT91 213 on its approach to periastron

abstract:
  The radio and gamma-ray pulsar PSR J2032+4127 was recently found to be in a
decades-long orbit with the Be star MT91 213, with the pulsar moving rapidly
towards periastron. This binary shares many similar characteristics with the
previously unique binary system PSR B1259-63/LS 2883. Here, we describe radio,
X-ray, and optical monitoring of PSR J2032+4127/MT91 213. Our extended orbital
phase coverage in radio, supplemented with Fermi gamma-ray data, allows us to
update and refine the orbital period to 45-50 yr and time of periastron passage
to 2017 November. We analyse archival and recent Chandra and Swift observations
and show that PSR J2032+4127/MT91 213 is now brighter in X-rays by a factor of
~70 since 2002 and ~20 since 2010. While the pulsar is still far from
periastron, this increase in X-rays is possibly due to collisions between
pulsar and Be star winds. Optical observations of the Halpha emission line of
the Be star suggest that the size of its circumstellar disc may be varying by
~2 over timescales as short as 1-2 months. Multiwavelength monitoring of PSR
J2032+4127/MT91 213 will continue through periastron passage, and the system
should present an interesting test case and comparison to PSR B1259-63/LS 2883.


title:
Many-Body Theory of Trion Absorption Features in Two-Dimensional
  Semiconductors

abstract:
  Recent optical studies of monolayer transition metal dechalcogenides have
demonstrated that their excitonic absorption feature splits into two widely
separated peaks at finite carrier densities. The additional peak is usually
attributed to the presence of trions, bound states of two electrons and a hole
or an electron and two holes. Here we argue that in the density range over
which the trion peak is well resolved, it cannot be interpreted in terms of
weakly coupled three-body systems, and that the appropriate picture is instead
one in which excitons are dressed by interactions with a Fermi sea of excess
carriers. This coupling splits the exciton spectrum into a lower energy
attractive exciton-polaron branch, normally identified as a trion branch, and a
higher energy repulsive exciton-polaron branch, normally identified as an
exciton branch. We have calculated the frequency and doping dependence of the
optical conductivity and found that: (i) the splitting varies linearly with the
Fermi energy of the excess quasiparticles; (ii) the trion peak is dominant at
high carrier densities; (iii) and the trion peak width is considerably smaller
than that of the excitonic peak. Our results are in good agreement with recent
experiments.


title: A Time-Dependent Wave-Thermoelastic Solid Interaction

abstract:
  This paper presents a combined field and boundary integral equation method
for solving the time-dependent scattering problem of a thermoelastic body
immersed in a compressible, inviscid and homogeneous fluid. The approach here
is a generalization of the coupling procedure employed by the authors for the
treatment of the time-dependent fluid-structure interaction problem. Using an
integral representation of the solution in the infinite exterior domain
occupied by the fluid, the problem is reduced to one defined only over the
finite region occupied by the solid, with nonlocal boundary conditions. The
nonlocal boundary problem is analyzed with Lubich's approach for time-dependent
boundary integral equations. Existence and uniqueness results are established
in terms of time-domain data with the aid of Laplace-domain techniques.
Galerkin semi-discretization approximations are derived and error estimates are
obtained. A full discretization based on the Convolution Quadrature method is
also outlined. Some numerical experiments in 2D are also included in order to
demonstrate the accuracy and efficiency of the procedure.


title: Max-affine estimators for convex stochastic programming

abstract:
  In this paper, we consider two sequential decision making problems with a
convexity structure, namely an energy storage optimization task and a
multi-product assembly example. We formulate these problems in the stochastic
programming framework and discuss an approximate dynamic programming technique
for their solutions. As the cost-to-go functions are convex in these cases, we
use max-affine estimates for their approximations. To train such a max-affine
estimate, we provide a new convex regression algorithm, and evaluate it
empirically for these planning scenarios.


title:
Radiative Transfer Modeling of Radio-band Linear Polarization
  Observations as a Probe of the Physical Conditions in the Jets of Gamma-ray
  Flaring Blazars

abstract:
  Since the mid-1980s the shock-in-jet model has been the preferred paradigm to
explain radio-band flaring in blazar jets. We describe our radiative transfer
model incorporating relativistically-propagating shocks, and illustrate how the
4.8, 8, and 14.5 GHz linear polarization and total flux density data from the
University of Michigan monitoring program, in combination with the model,
constrain jet flow conditions and shock attributes. Results from strong
Fermi-era flares in 4 blazars with widely-ranging properties are presented.
Additionally, to investigate jet evolution on decadal time scales we analyze 3
outbursts in OT 081 spanning nearly 3 decades and find intrinsic changes
attributable to flow changes at a common spatial location, or, alternatively,
to a change in the jet segment viewed. The model's success in reproducing these
data supports a scenario in which relativistic shocks compress a plasma with an
embedded passive, initially-turbulent magnetic field, with additional ordered
magnetic field components, one of which may be helical.


title:
Tailoring Thermal Conductivity of Single-stranded Carbon-chain Polymers
  through Atomic Mass Modification

abstract:
  Tailoring the thermal conductivity of polymers is central to enlarge their
applications in the thermal management of flexible integrated circuits.
Progress has been made over the past decade by fabricating materials with
various nanostructures, but a clear relationship between various functional
groups and thermal properties of polymers remains to be established. Here, we
numerically study the thermal conductivity of single-stranded carbon-chain
polymers with multiple substituents of hydrogen atoms through atomic mass
modification. We find that their thermal conductivity can be tuned by atomic
mass modifications as revealed through molecular dynamics simulations. The
simulation results suggest that heavy homogeneous substituents do not assist
heat transport and trace amounts of heavy substituents can in fact hinder heat
transport substantially. Our analysis indicates that carbon chain has the
biggest contribution (over 80%) to the thermal conduction in single-stranded
carbon-chain polymers. We further demonstrate that atomic mass modifications
influence the phonon bands of bonding carbon atoms, and the discrepancies of
phonon bands between carbon atoms are responsible for the remarkable drops in
thermal conductivity and large thermal resistances in carbon chains. Our study
provides fundamental insight into how to tailor the thermal conductivity of
polymers through variable substituents.


title: Blockage induced condensation controlled by a local reaction

abstract:
  We consider the set-up of stationary Zero Range models and discuss the onset
of condensation induced by a local blockage on the lattice. We show that the
introduction of a local feedback on the hopping rates allows to control the
particle fraction in the condensed phase. This phenomenon results in a current
vs. blockage parameter curve characterized by two non--analyticity points.


title:
Unsupervised learning of transcriptional regulatory networks via latent
  tree graphical models

abstract:
  Gene expression is a readily-observed quantification of transcriptional
activity and cellular state that enables the recovery of the relationships
between regulators and their target genes. Reconstructing transcriptional
regulatory networks from gene expression data is a problem that has attracted
much attention, but previous work often makes the simplifying (but unrealistic)
assumption that regulator activity is represented by mRNA levels. We use a
latent tree graphical model to analyze gene expression without relying on
transcription factor expression as a proxy for regulator activity. The latent
tree model is a type of Markov random field that includes both observed gene
variables and latent (hidden) variables, which factorize on a Markov tree.
Through efficient unsupervised learning approaches, we determine which groups
of genes are co-regulated by hidden regulators and the activity levels of those
regulators. Post-processing annotates many of these discovered latent variables
as specific transcription factors or groups of transcription factors. Other
latent variables do not necessarily represent physical regulators but instead
reveal hidden structure in the gene expression such as shared biological
function. We apply the latent tree graphical model to a yeast stress response
dataset. In addition to novel predictions, such as condition-specific binding
of the transcription factor Msn4, our model recovers many known aspects of the
yeast regulatory network. These include groups of co-regulated genes,
condition-specific regulator activity, and combinatorial regulation among
transcription factors. The latent tree graphical model is a general approach
for analyzing gene expression data that requires no prior knowledge of which
possible regulators exist, regulator activity, or where transcription factors
physically bind.


title:
Performing Hong-Ou-Mandel-type Numerical Experiments with Repulsive
  Condensates: The case of Dark and Dark-bright Solitons

abstract:
  The Hong-Ou-Mandel experiment leads indistinguishable photons simultaneously
reaching a 50:50 beam splitter to emerge on the same port through two-photon
interference. Motivated by this phenomenon, we consider numerical experiments
of the same flavor for classical, {\it wave} objects in the setting of
repulsive condensates. We examine dark solitons interacting with a repulsive
barrier, a case in which we find no significant asymmetries in the emerging
waves after the collision, presumably due to their topological nature. We also
consider case examples of two-component systems, where the dark solitons trap a
bright structure in the second-component (dark-bright solitary waves). For
these, pronounced asymmetries upon collision {\it are} possible for the
non-topological bright component. We also show an example of a similar
phenomenology for ring dark-bright structures in two dimensions.


title:
Hydrocarbon emission rings in protoplanetary disks induced by dust
  evolution

abstract:
  We report observations of resolved C2H emission rings within the gas-rich
protoplanetary disks of TW Hya and DM Tau using the Atacama Large Millimeter
Array (ALMA). In each case the emission ring is found to arise at the edge of
the observable disk of mm-sized grains (pebbles) traced by (sub)mm-wave
continuum emission. In addition, we detect a C3H2 emission ring with an
identical spatial distribution to C2H in the TW Hya disk. This suggests that
these are hydrocarbon rings (i.e. not limited to C2H). Using a detailed
thermo-chemical model we show that reproducing the emission from C2H requires a
strong UV field and C/O > 1 in the upper disk atmosphere and outer disk, beyond
the edge of the pebble disk. This naturally arises in a disk where the
ice-coated dust mass is spatially stratified due to the combined effects of
coagulation, gravitational settling and drift. This stratification causes the
disk surface and outer disk to have a greater permeability to UV photons.
Furthermore the concentration of ices that transport key volatile carriers of
oxygen and carbon in the midplane, along with photochemical erosion of CO,
leads to an elemental C/O ratio that exceeds unity in the UV-dominated disk.
Thus the motions of the grains, and not the gas, lead to a rich hydrocarbon
chemistry in disk surface layers and in the outer disk midplane.


title:
Assessing the Impact of Retreat Mechanisms in a Simple Antarctic Ice
  Sheet Model Using Bayesian Calibration

abstract:
  The response of the Antarctic ice sheet (AIS) to changing climate forcings is
an important driver of sea-level changes. Anthropogenic climate change may
drive a sizeable AIS tipping point response with subsequent increases in
coastal flooding risks. Many studies analyzing flood risks use simple models to
project the future responses of AIS and its sea-level contributions. These
analyses have provided important new insights, but they are often silent on the
effects of potentially important processes such as Marine Ice Sheet Instability
(MISI) or Marine Ice Cliff Instability (MICI). These approximations can be well
justified and result in more parsimonious and transparent model structures.
This raises the question of how this approximation impacts hindcasts and
projections. Here, we calibrate a previously published and relatively simple
AIS model, which neglects the effects of MICI and regional characteristics,
using a combination of observational constraints and a Bayesian inversion
method. Specifically, we approximate the effects of missing MICI by comparing
our results to those from expert assessments with more realistic models and
quantify the bias during the last interglacial when MICI may have been
triggered. Our results suggest that the model can approximate the process of
MISI and reproduce the projected median melt from some previous expert
assessments in the year 2100. Yet, our mean hindcast is roughly 3/4 of the
observed data during the last interglacial period and our mean projection is
roughly 1/6 and 1/10 of the mean from a model accounting for MICI in the year
2100. These results suggest that missing MICI and/or regional characteristics
can lead to a low-bias during warming period AIS melting and hence a potential
low-bias in projected sea levels and flood risks.


title: Profiting from correlations: Adjusted estimators for categorical data

abstract:
  To take sample biases and skewness in the observations into account,
practitioners frequently weight their observations according to some marginal
distribution. The present paper demonstrates that such weighting can indeed
improve the estimation. Studying contingency tables, estimators for marginal
distributions are proposed under the assumption that another marginal is known.
It is shown that the weighted estimators have a strictly smaller asymptotic
variance whenever the two marginals are correlated. The finite sample
performance is illustrated in a simulation study. As an application to traffic
accident data the method allows for correcting a well-known bias in the
observed injury severity distribution.


title: Pattern Recognition In Non-Kolmogorovian Structures

abstract:
  We present a generalization of the problem of pattern recognition to
arbitrary probabilistic models. This version deals with the problem of
recognizing an individual pattern among a family of different species or
classes of objects which obey probabilistic laws which do not comply with
Kolmogorov's axioms. We show that such a scenario accommodates many important
examples, and in particular, we provide a rigorous definition of the classical
and the quantum pattern recognition problems, respectively. Our framework
allows for the introduction of non-trivial correlations (as entanglement or
discord) between the different species involved, opening the door to a new way
of harnessing these physical resources for solving pattern recognition
problems. Finally, we present some examples and discuss the computational
complexity of the quantum pattern recognition problem, showing that the most
important quantum computation algorithms can be described as non-Kolmogorovian
pattern recognition problems.


title: Markov Random Field Model-Based Salt and Pepper Noise Removal

abstract:
  Problem of impulse noise reduction is a very well studied problem in image
processing community and many different approaches have been proposed to tackle
this problem. In the current work, the problem of fixed value impulse noise
(salt and pepper) removal from images is investigated by use of a Markov Random
Field (MRF) models with smoothness priors. After the formulation of the problem
as an inpainting problem, graph cuts with $\alpha$-expansion moves are
considered for minimization of the energy functional. As for comparisons,
several other minimization techniques that are widely used for MRF models'
optimization are considered and the results are compared using
Peak-Signal-to-Noise-Ratio (PSNR) and Structural Similarity Index (SSIM) as
metrics. The investigations show the superiority of graph cuts with
$\alpha$-expansion moves over the other techniques both in terms of PSNR and
also computational times.


title:
Finding Linear-Recurrent Solutions to Hofstadter-Like Recurrences Using
  Symbolic Computation

abstract:
  The Hofstadter Q-sequence, with its simple definition, has defied all
attempts at analyzing its behavior. Defined by a simple nested recurrence and
an initial condition, the sequence looks approximately linear, though with a
lot of noise. But, nobody even knows whether the sequence is infinite. In the
years since Hofstadter published his sequence, various people have found
variants with predictable behavior. Oftentimes, the resulting sequence looks
complicated but provably grows linearly. Other times, the sequences are
eventually linear recurrent. Proofs describing the behaviors of both types of
sequence are inductive. In the first case, the inductive hypotheses are fairly
ad-hoc, but the proofs in the second case are highly automatable. This suggests
that a search for more sequences like these may be fruitful. In this paper, we
develop a step-by-step symbolic algorithm to search for these sequences. Using
this algorithm, we determine that such sequences come in infinite families that
are themselves plentiful. In fact,there are hundreds of easy to describe
families based on the Hofstadter Q-recurrence alone.


title: The Asymptotics of Representations for Cyclic Opers

abstract:
  Given a Riemann surface $X = (\Sigma, J)$ we find an expression for the
dominant term for the asymptotics of the holonomy of opers over that Riemann
surface corresponding to rays in the Hitchin base of the form
$(0,0,\cdots,t\omega_n)$. Moreover, we find an associated equivariant map from
the universal cover $(\tilde{\Sigma},\tilde{J})$ to the symmetric space
SL$_n(\mathbb{C}) / \mbox{SU}(n)$ and show that limits of these maps tend to a
sub-building in the asymptotic cone. That sub-building is explicitly
constructed from the local data of $\omega_n$.


title:
Controlling the Multiport Nature of Bragg Diffraction in Atom
  Interferometry

abstract:
  Bragg diffraction has been used in atom interferometers because it allows
signal enhancement through multiphoton momentum transfer and suppression of
systematics by not changing the internal state of atoms. Its multi-port nature,
however, can lead to parasitic interferometers, allows for intensity-dependent
phase shifts in the primary interferometers, and distorts the ellipses used for
phase extraction. We study and suppress these unwanted effects. Specifically,
phase extraction by ellipse fitting and the resulting systematic phase shifts
are calculated by Monte Carlo simulations. Phase shifts arising from the
thermal motion of the atoms are controlled by spatial selection of atoms and an
appropriate choice of Bragg intensity. In these simulations, we found that
Gaussian Bragg pulse shapes yield the smallest systematic shifts. Parasitic
interferometers are suppressed by a "magic" Bragg pulse duration. The
sensitivity of the apparatus was improved by the addition of AC Stark shift
compensation, which permits direct experimental study of sub-part-per-billion
(ppb) systematics. This upgrade allows for a 310\,$\hbar k$ momentum transfer,
giving an unprecedented 6.6\,Mrad measured in a Ramsey-Bord\'e interferometer.


title:
Entwicklung eines Reputationssystems f\"ur cyber-physikalische Systeme
  am Beispiel des inHMotion Forschungsprojektes

abstract:
  Through the continued progress and advances of networking technology and also
through efforts like Industry 4.0, SmartGrid, SmartCities, systems, that have
been self-sustaining for the most part are now forming networked Cyber-physical
Systems (CPS). Networking does not only have undoubtely benefits but also
increase the often overlooked attack surface of these systems. A basic problem
in information technology systems is building and sustaining trust. This work
looks at the usage of reputation systems in the field of CPS and whether they
could be used to assert the trustworthyness of communication partners. This is
done in context of a research project inHMotion of the University of applied
Sciences Munich, which is in the field of Intelligent Transportation Systems
(ITS). A risk based analysis is performed for this project. Based on solicited
threats mitigations are proposed. A possible solution might be the usage of a
reputation system, which is designed and a prototype implementation for a
simulation ist done. The concept of a meta reputation system, which combines
different reputation systems and verification systems can achieve promising
results in a simple simulation. In a concluding discussion criticism and
possible improvements are given.


title: An approximate version of a conjecture of Aharoni and Berger

abstract:
  Aharoni and Berger conjectured that in every proper edge-colouring of a
bipartite multigraph by $n$ colours with at least $n+1$ edges of each colour
there is a rainbow matching using every colour. This conjecture generalizes a
longstanding problem of Brualdi and Stein about transversals in Latin squares.
Here an approximate version of the Aharoni-Berger Conjecture is proved---it is
shown that if there are at least $n+o(n)$ edges of each colour in a proper
$n$-edge-colouring of a bipartite multigraph then there is a rainbow matching
using every colour.


title: Stabilizing Embedology: Geometry-Preserving Delay-Coordinate Maps

abstract:
  Delay-coordinate mapping is an effective and widely used technique for
reconstructing and analyzing the dynamics of a nonlinear system based on
time-series outputs. The efficacy of delay-coordinate mapping has long been
supported by Takens' embedding theorem, which guarantees that delay-coordinate
maps use the time-series output to provide a reconstruction of the hidden state
space that is a one-to-one embedding of the system's attractor. While this
topological guarantee ensures that distinct points in the reconstruction
correspond to distinct points in the original state space, it does not
characterize the quality of this embedding or illuminate how the specific
parameters affect the reconstruction. In this paper, we extend Takens' result
by establishing conditions under which delay-coordinate mapping is guaranteed
to provide a stable embedding of a system's attractor. Beyond only preserving
the attractor topology, a stable embedding preserves the attractor geometry by
ensuring that distances between points in the state space are approximately
preserved. In particular, we find that delay-coordinate mapping stably embeds
an attractor of a dynamical system if the stable rank of the system is large
enough to be proportional to the dimension of the attractor. The stable rank
reflects the relation between the sampling interval and the number of delays in
delay-coordinate mapping. Our theoretical findings give guidance to choosing
system parameters, echoing the trade-off between irrelevancy and redundancy
that has been heuristically investigated in the literature. Our initial result
is stated for attractors that are smooth submanifolds of Euclidean space, with
extensions provided for the case of strange attractors.


title: The Minimum Halo Mass for Star Formation at z = 6 - 8

abstract:
  Recent analysis of strongly-lensed sources in the Hubble Frontier Fields
indicates that the rest-frame UV luminosity function of galaxies at $z=$6--8
rises as a power law down to $M_\mathrm{UV}=-15$, and possibly as faint as
-12.5. We use predictions from a cosmological radiation hydrodynamic simulation
to map these luminosities onto physical space, constraining the minimum dark
matter halo mass and stellar mass that the Frontier Fields probe. While
previously-published theoretical studies have suggested or assumed that early
star formation was suppressed in halos less massive than $10^9$--$10^{11}
M_\odot$, we find that recent observations demand vigorous star formation in
halos at least as massive as (3.1, 5.6, 10.5)$\times10^9 M_\odot$ at
$z=(6,7,8)$. Likewise, we find that Frontier Fields observations probe down to
stellar masses of (8.1, 18, 32)$\times10^6 M_\odot$; that is, they are
observing the likely progenitors of analogues to Local Group dwarfs such as
Pegasus and M32. Our simulations yield somewhat different constraints than two
complementary models that have been invoked in similar analyses, emphasizing
the need for further observational constraints on the galaxy-halo connection.


title:
A review of matrix scaling and Sinkhorn's normal form for matrices and
  positive maps

abstract:
  Given a nonnegative matrix $A$, can you find diagonal matrices $D_1,~D_2$
such that $D_1AD_2$ is doubly stochastic? The answer to this question is known
as Sinkhorn's theorem. It has been proved with a wide variety of methods, each
presenting a variety of possible generalisations. Recently, generalisations
such as to positive maps between matrix algebras have become more and more
interesting for applications. This text gives a review of over 70 years of
matrix scaling. The focus lies on the mathematical landscape surrounding the
problem and its solution as well as the generalisation to positive maps and
contains hardly any nontrivial unpublished results.


title:
Extension of the osp(m|n)~ so(m-n) Correspondence to the
  Infinite-Dimensional Chiral Spinors and Self Dual Tensors

abstract:
  The spinor representations of the orthosymplectic Lie superalgebras osp(m|n)
are considered and constructed. These are infinite-dimensional irreducible
representations, of which the superdimension coincides with the dimension of
the spinor representation of so(m-n). Next, we consider the self dual tensor
representations of osp(m|n) and their generalizations: these are also
infinite-dimensional and correspond to the highest irreducible component of the
$p^{th}$ power of the spinor representation. We determine the character of
these representations, and deduce a superdimension formula. From this, it
follows that also for these representations the osp(m|n)~ so(m-n)
correspondence holds.


title: Cosmology with Independently Varying Neutrino Temperature and Number

abstract:
  We consider Big Bang nucleosynthesis and the cosmic microwave background when
both the neutrino temperature and neutrino number are allowed to vary from
their standard values. The neutrino temperature is assumed to differ from its
standard model value by a fixed factor from Big Bang nucleosynthesis up to the
present. In this scenario, the effective number of relativistic degrees of
freedom, $N_{\rm eff}^{\rm CMB}$, derived from observations of the cosmic
microwave background is not equal to the true number of neutrinos, $N_\nu$. We
determine the element abundances predicted by Big Bang nucleosynthesis as a
function of the neutrino number and temperature, converting the latter to the
equivalent value of $N_{\rm eff}^{\rm CMB}$. We find that a value of $N_{\rm
eff}^{\rm CMB} \approx 3$ can be made consistent with $N_\nu = 4$ with a
decrease in the neutrino temperature of $\sim 5\%$, while $N_\nu = 5$ is
excluded for any value of $N_{\rm eff}^{\rm CMB}$. No observationally-allowed
values for $N_{\rm eff}^{\rm CMB}$ and $N_\nu$ can solve the lithium problem.


title:
Magnetic field dependence of the internal quality factor and noise
  performance of lumped-element kinetic inductance detectors

abstract:
  We present a technique for increasing the internal quality factor of kinetic
inductance detectors (KIDs) by nulling ambient magnetic fields with a properly
applied magnetic field. The KIDs used in this study are made from thin-film
aluminum, they are mounted inside a light-tight package made from bulk
aluminum, and they are operated near $150 \, \mathrm{mK}$. Since the thin-film
aluminum has a slightly elevated critical temperature ($T_\mathrm{c} = 1.4 \,
\mathrm{K}$), it therefore transitions before the package ($T_\mathrm{c} = 1.2
\, \mathrm{K}$), which also serves as a magnetic shield. On cooldown, ambient
magnetic fields as small as approximately $30 \, \mathrm{\mu T}$ can produce
vortices in the thin-film aluminum as it transitions because the bulk aluminum
package has not yet transitioned and therefore is not yet shielding. These
vortices become trapped inside the aluminum package below $1.2 \, \mathrm{K}$
and ultimately produce low internal quality factors in the thin-film
superconducting resonators. We show that by controlling the strength of the
magnetic field present when the thin film transitions, we can control the
internal quality factor of the resonators. We also compare the noise
performance with and without vortices present, and find no evidence for excess
noise beyond the increase in amplifier noise, which is expected with increasing
loss.


title: Degraded Broadcast Channel with Secrecy Outside a Bounded Range

abstract:
  The $K$-receiver degraded broadcast channel with secrecy outside a bounded
range is studied, in which a transmitter sends $K$ messages to $K$ receivers,
and the channel quality gradually degrades from receiver $K$ to receiver 1.
Each receiver $k$ is required to decode message $W_1,\ldots,W_k$, for $1\leq
k\leq K$, and to be kept ignorant of $W_{k+2},\ldots,W_K$, for $k=1,\ldots,
K-2$. Thus, each message $W_k$ is kept secure from receivers with at least
two-level worse channel quality, i.e., receivers 1, $\ldots$, $k-2$. The
secrecy capacity region is fully characterized. The achievable scheme
designates one superposition layer to each message with binning employed for
each layer. Joint embedded coding and binning are employed to protect all
upper-layer messages from lower-layer receivers. Furthermore, the scheme allows
adjacent layers to share rates so that part of the rate of each message can be
shared with its immediate upper-layer message to enlarge the rate region. More
importantly, an induction approach is developed to perform Fourier-Motzkin
elimination of $2K$ variables from the order of $K^2$ bounds to obtain a
close-form achievable rate region. An outer bound is developed that matches the
achievable rate region, whose proof involves recursive construction of the rate
bounds and exploits the intuition gained from the achievable scheme.


title:
Recognizing Detailed Human Context In-the-Wild from Smartphones and
  Smartwatches

abstract:
  The ability to automatically recognize a person's behavioral context can
contribute to health monitoring, aging care and many other domains. Validating
context recognition in-the-wild is crucial to promote practical applications
that work in real-life settings. We collected over 300k minutes of sensor data
with context labels from 60 subjects. Unlike previous studies, our subjects
used their own personal phone, in any way that was convenient to them, and
engaged in their routine in their natural environments. Unscripted behavior and
unconstrained phone usage resulted in situations that are harder to recognize.
We demonstrate how fusion of multi-modal sensors is important for resolving
such cases. We present a baseline system, and encourage researchers to use our
public dataset to compare methods and improve context recognition in-the-wild.


title: Outlaw distributions and locally decodable codes

abstract:
  Locally decodable codes (LDCs) are error correcting codes that allow for
decoding of a single message bit using a small number of queries to a corrupted
encoding. Despite decades of study, the optimal trade-off between query
complexity and codeword length is far from understood. In this work, we give a
new characterization of LDCs using distributions over Boolean functions whose
expectation is hard to approximate (in~$L_\infty$~norm) with a small number of
samples. We coin the term `outlaw distributions' for such distributions since
they `defy' the Law of Large Numbers. We show that the existence of outlaw
distributions over sufficiently `smooth' functions implies the existence of
constant query LDCs and vice versa. We give several candidates for outlaw
distributions over smooth functions coming from finite field incidence
geometry, additive combinatorics and from hypergraph (non)expanders.
  We also prove a useful lemma showing that (smooth) LDCs which are only
required to work on average over a random message and a random message index
can be turned into true LDCs at the cost of only constant factors in the
parameters.


title: Review on carrier multiplication in graphene

abstract:
  The remarkable gapless and linear band structure of graphene opens up new
carrier relaxation channels bridging the valence and the conduction band. These
Auger scattering processes change the number of charge carriers and can give
rise to a significant multiplication of optically excited carriers in graphene.
This is an ultrafast many-particle phenomenon that is of great interest both
for fundamental many-particle physics as well as technological applications.
Here, we review the research on carrier multiplication in graphene and
Landau-quantized graphene including theoretical modelling and experimental
demonstration.


title:
Sparse Blind Deconvolution and Demixing Through
  $\ell_{1,2}$-Minimization

abstract:
  This paper concerns solving the sparse deconvolution and demixing problem
using $\ell_{1,2}$-minimization. We show that under a certain structured random
model, robust and stable recovery is possible. The results extend results of
Ling and Strohmer [Self Calibration and Biconvex Compressive Sensing, Inverse
Problems, 2015], and in particular theoretically explain certain experimental
findings from that paper. Our results do not only apply to the deconvolution
and demixing problem, but to recovery of column-sparse matrices in general.


title:
Breakdown of the equivalence between active gravitational mass and
  energy for a quantum body

abstract:
  We determine active gravitational mass operator of the simplest composite
quantum body - a hydrogen atom - within the semiclassical approach to the
Einstein equation for a gravitational field. We show that the expectation value
of the mass is equivalent to energy for stationary quantum states. On the other
hand, it occurs that, for quantum superpositions of stationary states with
constant expectation values of energy, the expectation values of the
gravitational mass exhibit time-dependent oscillations. This breaks the
equivalence between active gravitational mass and energy and can be observed as
a macroscopic effect for a macroscopic ensemble of coherent quantum states of
the atoms. The corresponding experiment could be the first direct observation
of quantum effects in General Relativity.


title:
Game among Interdependent Networks: The Impact of Rationality on System
  Robustness

abstract:
  Many real-world systems are composed of interdependent networks that rely on
one another. Such networks are typically designed and operated by different
entities, who aim at maximizing their own payoffs. There exists a game among
these entities when designing their own networks. In this paper, we study the
game investigating how the rational behaviors of entities impact the system
robustness. We first introduce a mathematical model to quantify the interacting
payoffs among varying entities. Then we study the Nash equilibrium of the game
and compare it with the optimal social welfare. We reveal that the cooperation
among different entities can be reached to maximize the social welfare in
continuous game only when the average degree of each network is constant.
Therefore, the huge gap between Nash equilibrium and optimal social welfare
generally exists. The rationality of entities makes the system inherently
deficient and even renders it extremely vulnerable in some cases. We analyze
our model for two concrete systems with continuous strategy space and discrete
strategy space, respectively. Furthermore, we uncover some factors (such as
weakening coupled strength of interdependent networks, designing suitable
topology dependency of the system) that help reduce the gap and the system
vulnerability.


title:
Grassmann phase-space methods for fermions: uncovering classical
  probability structure

abstract:
  The phase-space description of bosonic quantum systems has numerous
applications in such fields as quantum optics, trapped ultracold atoms, and
transport phenomena. Extension of this description to the case of fermionic
systems leads to formal Grassmann phase-space quasiprobability distributions
and master equations. The latter are usually considered as not possessing
probabillistic interpretation and as not directly computationally accessible.
Here, we describe how to construct $c$-number interpretations of Grassmann
phase space representations and their master equations. As a specific example,
the Grassmann $B$ representation is considered. We disscuss how to introduce
$c$-number probability distributions on Grassmann algebra and how to integrate
them. A measure of size and proximity is defined for Grassmann numbers, and the
Grassmann derivatives are introduced which are based on infinitesimal
variations of function arguments. An example of $c$-number interpretation of
formal Grassmann equations is presented.

categories: quant-ph cond-mat.quant-gas math-ph math.MP


title: Prethermalization from a low-density Holstein-Primakoff expansion

abstract:
  We consider the non-equilibrium dynamics arising after a quench of the
transverse magnetic field of a quantum Ising chain, together with the sudden
switch-on of a long-range interaction term. The dynamics after the quantum
quench is mapped onto a fully-connected model of hard-core bosons, after a
suitable combination of a Holstein-Primakoff transformation and of a
low-density expansion in the quasi-particles injected by the quench. This
mapping holds for a broad class of initial states and for quenches which do not
cross the critical point of the transverse field Ising model. We then study the
algebraic relaxation in time of a number of observables towards a metastable,
pre-thermal state, which becomes the asymptotic steady state in the
thermodynamic limit.


title:
Impact of the tidal p-g instability on the gravitational wave signal
  from coalescing binary neutron stars

abstract:
  Recent studies suggest that coalescing neutron stars are subject to a fluid
instability involving the nonlinear coupling of the tide to $p$-modes and
$g$-modes. Its influence on the inspiral dynamics and thus the gravitational
wave signal is, however, uncertain because we do not know precisely how the
instability saturates. Here we construct a simple, physically motivated model
of the saturation that allows us to explore the instability's impact as a
function of the model parameters. We find that for plausible assumptions about
the saturation, current gravitational wave detectors might miss $> 70\%$ of
events if only point particle waveforms are used. Parameters such as the chirp
mass, component masses, and luminosity distance might also be significantly
biased. On the other hand, we find that relatively simple modifications to the
point particle waveform can alleviate these problems and enhance the science
that emerges from the detection of binary neutron stars.


title:
Stationary averaging for multi-scale continuous time Markov chains using
  parallel replica dynamics

abstract:
  We propose two algorithms for simulating continuous time Markov chains in the
presence of metastability. We show that the algorithms correctly estimate,
under the ergodicity assumption, stationary averages of the process. Both
algorithms, based on the idea of the parallel replica method, use parallel
computing in order to explore metastable sets more efficiently. The algorithms
require no assumptions on the Markov chains beyond ergodicity and the presence
of identifiable metastability.
  In particular, there is no assumption on reversibility. For simpler
illustration of the algorithms, we assume that a synchronous architecture is
used throughout of the paper. We present error analyses, as well as numerical
simulations on multi-scale stochastic reaction network models in order to
demonstrate consistency of the method and its efficiency.


title: Sparse Bounds for Oscillatory and Random Singular Integrals

abstract:
  Let $ T_{P } f (x) = \int e ^{i P (y)} K (y) f (x-y) \; dy $, where $ K (y)$
is a smooth Calder\'on-Zygmund kernel on $ \mathbb R ^{n}$, and $ P$ be a
polynomial. We show that there is a sparse bound for the bilinear form $
\langle T_P f, g \rangle$. This in turn easily implies $ A_p $ inequalities.
The method of proof is applied in a random discrete setting, yielding the first
weighted inequalities for operators defined on sparse sets of integers.


title:
Phenomenological Implications of the $p_T$ Spectra of $\phi$ and
  $\Omega$ produced at LHC and RHIC

abstract:
  The data on the $p_T$ spectra of $\phi$ and $\Omega$ at LHC can be presented
in a format that shows exponential behavior up to $p_T\approx 6$ GeV/c with the
same slope for both particles and for nearly all centralities. They are
empirical properties that are shared at lower energies with the inverse slope
showing a power-law dependence on $\sqrt{s_{NN}}$. The shared properties of the
spectra are shown to emerge naturally from the recombination model. No flow is
needed. We find experimental hints for the possibility that $\phi$ and $\Omega$
are mostly produced in the ridge that are generated by minijets. Appropriate
experimental test is suggested.


title: The JCMT Gould Belt Survey: Dense Core Clusters in Orion A

abstract:
  The Orion A molecular cloud is one of the most well-studied nearby
star-forming regions, and includes regions of both highly clustered and more
dispersed star formation across its full extent. Here, we analyze dense,
star-forming cores identified in the 850 {\mu}m and 450 {\mu}m SCUBA-2 maps
from the JCMT Gould Belt Legacy Survey. We identify dense cores in a uniform
manner across the Orion A cloud and analyze their clustering properties. Using
two independent lines of analysis, we find evidence that clusters of dense
cores tend to be mass segregated, suggesting that stellar clusters may have
some amount of primordial mass segregation already imprinted in them at an
early stage. We also demonstrate that the dense core clusters have a tendency
to be elongated, perhaps indicating a formation mechanism linked to the
filamentary structure within molecular clouds.


title:
Anomalous Hall hysteresis in Tm3Fe5O12/Pt with strain-induced
  perpendicular magnetic anisotropy

abstract:
  We demonstrate robust interface strain-induced perpendicular magnetic
anisotropy in atomically flat ferrimagnetic insulator Tm3Fe5O12 films grown
with pulsed laser deposition on substituted-Gd3Ga5O12 substrate which maximizes
the tensile strain at the interface. In bilayers consisting of Pt and TIG, we
observe large squared Hall hysteresis loops over a wide range of thicknesses of
Pt at room temperature. When a thin Cu layer is inserted between Pt and TIG,
the Hall hysteresis magnitude decays but stays finite as the thickness of Cu
increases up to 5 nm. However, if the Cu layer is placed atop Pt instead, the
Hall hysteresis magnitude is consistently larger than when the Cu layer with
the same thickness is inserted in between for all Cu thicknesses. These results
suggest that both the proximity-induced ferromagnetism and spin current
contribute to the anomalous Hall effect.