title:
Dynamical phase transition in large deviation statistics of the
  Kardar-Parisi-Zhang equation

abstract:
  We study the short-time behavior of the probability distribution
$\mathcal{P}(H,t)$ of the surface height $h(x=0,t)=H$ in the
Kardar-Parisi-Zhang (KPZ) equation in $1+1$ dimension. The process starts from
a stationary interface: $h(x,t=0)$ is given by a realization of two-sided
Brownian motion constrained by $h(0,0)=0$. We find a singularity of the large
deviation function of $H$ at a critical value $H=H_c$. The singularity has the
character of a second-order phase transition. It reflects spontaneous breaking
of the reflection symmetry $x \leftrightarrow -x$ of optimal paths $h(x,t)$
predicted by the weak-noise theory of the KPZ equation. At $|H|\gg |H_c|$ the
corresponding tail of $\mathcal{P}(H)$ scales as $-\ln \mathcal{P} \sim
|H|^{3/2}/t^{1/2}$ and agrees, at any $t>0$, with the proper tail of the
Baik-Rains distribution, previously observed only at long times. The other tail
of $\mathcal{P}$ scales as $-\ln \mathcal{P} \sim |H|^{5/2}/t^{1/2}$ and
coincides with the corresponding tail for the sharp-wedge initial condition.


title:
Stability of closed solutions to the VFE hierarchy with application to
  the Hirota equation

abstract:
  The Vortex Filament Equation (VFE) is part of an integrable hierarchy of
filament equations. Several equations part of this hierarchy have been derived
to describe vortex filaments in various situations. Inspired by these results,
we develop a general framework for studying the existence and the linear
stability of closed solutions of the VFE hierarchy. The framework is based on
the correspondence between the VFE and the nonlinear Schr\"odinger (NLS)
hierarchies. Our results show that it is possible to establish a connection
between the AKNS Floquet spectrum and the stability properties of the solutions
of the filament equations. We apply our machinery to solutions of the filament
equation associated to the Hirota equation. We also discuss how our framework
applies to soliton solutions.


title:
Alternating Anderson-Richardson method: An efficient alternative to
  preconditioned Krylov methods for large, sparse linear systems

abstract:
  We present the Alternating Anderson-Richardson (AAR) method: an efficient and
scalable alternative to preconditioned Krylov solvers for the solution of
large, sparse linear systems on high performance computing platforms.
Specifically, we generalize the recently proposed Alternating Anderson-Jacobi
(AAJ) method (Pratapa et al., J. Comput. Phys. (2016), 306, 43--54) to include
preconditioning, discuss efficient parallel implementation, and provide serial
MATLAB and parallel C/C++ implementations. In serial applications to
nonsymmetric systems, we find that AAR is comparably robust to GMRES, using the
same preconditioning, while often outperforming it in time to solution; and
find AAR to be more robust than Bi-CGSTAB for the problems considered. In
parallel applications to the Helmholtz and Poisson equations, we find that AAR
shows superior strong and weak scaling to GMRES, Bi-CGSTAB, and Conjugate
Gradient (CG) methods, using the same preconditioning, with consistently
shorter times to solution at larger processor counts. Finally, in massively
parallel applications to the Poisson equation, on up to 110,592 processors, we
find that AAR shows superior strong and weak scaling to CG, with shorter
minimum time to solution. We thus find that AAR offers a robust and efficient
alternative to current state-of-the-art solvers, with increasing advantages as
the number of processors grows.


title: Dynamic Watermarking: Active Defense of Networked Cyber-Physical Systems

abstract:
  The coming decades may see the large scale deployment of networked
cyber-physical systems to address global needs in areas such as energy, water,
healthcare, and transportation. However, as recent events have shown, such
systems are vulnerable to cyber attacks. Being safety critical, their
disruption or misbehavior can cause economic losses or injuries and loss of
life. It is therefore important to secure such networked cyber-physical systems
against attacks. In the absence of credible security guarantees, there will be
resistance to the proliferation of cyber-physical systems, which are much
needed to meet global needs in critical infrastructures and services.
  This paper addresses the problem of secure control of networked
cyber-physical systems. This problem is different from the problem of securing
the communication network, since cyber-physical systems at their very essence
need sensors and actuators that interface with the physical plant, and
malicious agents may tamper with sensors or actuators, as recent attacks have
shown.
  We consider physical plants that are being controlled by multiple actuators
and sensors communicating over a network, where some sensors could be
"malicious," meaning that they may not report the measurements that they
observe. We address a general technique by which the actuators can detect the
actions of malicious sensors in the system, and disable closed-loop control
based on their information. This technique, called "watermarking," employs the
technique of actuators injecting private excitation into the system which will
reveal malicious tampering with signals. We show how such an active defense can
be used to secure networked systems of sensors and actuators.


title: The radio evolution of supernova SN$\,$2008iz in M$\,$82

abstract:
  We report on multi-frequency Very Large Array (VLA) and Very Long Baseline
Interferometry (VLBI) radio observations for a monitoring campaign of supernova
SN$\,$2008iz in the nearby irregular galaxy M$\,$82. We fit two models to the
data, a simple time power-law, S$\propto$ t$^\beta$, and a simplified Weiler
model, yielding decline indices, $\beta$ of -1.22$\pm$0.07 (days 100-1500) and
-1.41$\pm$0.02 (days 76-2167), respectively. The late-time radio light curve
evolution shows flux-density flares at $\sim\,$970 and $\sim\,$1400 days which
are a factor of $\sim\,$2 and $\sim\,$4 higher than the expected flux,
respectively. The later flare, besides being brighter, does not show signs of
decline at least from results examined so far (2014 January 23, day 2167). We
derive the spectral index, $\alpha$, S$\propto$ $\nu^\alpha$ for frequencies
1.4 to 43$\,$GHz for SN$\,$2008iz during the period from $\sim\,$430 to 2167
days after the supernova explosion. The value of $\alpha$ shows no signs of
evolution and remains steep $\approx$$-$1 throughout the period, unlike that of
SN$\,$1993J which started flattening at $\sim\,$day 970. From the 4.8 and
8.4$\,$GHz VLBI images, the supernova expansion is seen to start with shell
like structure that gets more and more asymmetric, then breaks up in the later
epochs with bright structures dominating the southern part of the ring. This
structural evolution differs significantly from SN$\,$1993J, which remains
circularly symmetric over 4000 days after the explosion. The VLBI 4.8 and
8.4$\,$GHz images are used to derive a deceleration index, $m$, for
SN$\,$2008iz, of 0.86$\,\pm\,$0.02, and the average expansion velocity between
days 73 and 1400 as (12.1$\pm$0.2)$\times$10$^{3}\,$km$\,$s$^{-1}$.


title:
Monotonicity-preserving finite element schemes based on differentiable
  nonlinear stabilization

abstract:
  In this work, we propose a nonlinear stabilization technique for scalar
conservation laws with implicit time stepping. The method relies on an
artificial diffusion method, based on a graph-Laplacian operator. It is
nonlinear, since it depends on a shock detector. The same shock detector is
used to gradually lump the mass matrix. The resulting method is LED, positivity
preserving, linearity preserving, and also satisfies a global DMP. Lipschitz
continuity has also been proved. However, the resulting scheme is highly
nonlinear, leading to very poor nonlinear convergence rates. We propose a
smooth version of the scheme, which leads to twice differentiable nonlinear
stabilization schemes. It allows one to straightforwardly use Newton's method
and obtain quadratic convergence. In the numerical experiments, steady and
transient linear transport, and transient Burgers' equation have been
considered in 2D. Using the Newton method with a smooth version of the scheme
we can reduce 10 to 20 times the number of iterations of Anderson acceleration
with the original non-smooth scheme. In any case, these properties are only
true for the converged solution, but not for iterates. In this sense, we have
also proposed the concept of projected nonlinear solvers, where a projection
step is performed at the end of every nonlinear iteration onto a FE space of
admissible solutions. The space of admissible solutions is the one that
satisfies the desired monotonic properties (maximum principle or positivity).


title:
A new method to assign galaxy cluster membership using photometric
  redshifts

abstract:
  We introduce a new effective strategy to assign group and cluster membership
probabilities $P_{mem}$ to galaxies using photometric redshift information.
Large dynamical ranges both in halo mass and cosmic time are considered. The
method takes the magnitude distribution of both cluster and field galaxies as
well as the radial distribution of galaxies in clusters into account using a
non-parametric formalism and relies on Bayesian inference to take photometric
redshift uncertainties into account. We successfully test the method against
1,208 galaxy clusters within redshifts $z=0.05-2.58$ and masses
$10^{13.29-14.80}~M_\odot$ drawn from wide field simulated galaxy mock catalogs
developed for the Euclid mission. Median purity $(55^{+17}_{-15})\%$ and
completeness $(95^{+5}_{-10})\%$ are reached for galaxies brighter than
0.25$L_\ast$ within $r_{200}$ of each simulated halo and for a statistical
photometric redshift accuracy $\sigma((z_s-z_p)/(1+z_s))=0.03$. The mean values
$p=56\%$ and $c=93\%$ have sub-percent uncertainties. Accurate photometric
redshifts ($\sigma((z_s-z_p)/(1+z_s))\lesssim0.05$) and robust estimates for
the cluster redshift and the center coordinates are required. The method is
applied to derive accurate richness estimates. A statistical comparison between
the true ($N_{\rm true}$) vs estimated richness ($\lambda=\sum P_{mem}$) yields
on average to unbiased results, $Log(\lambda/N_{\rm true})=-0.0051\pm0.15$. The
scatter around the mean of the logarithmic difference between $\lambda$ and the
halo mass is 0.10~dex, for massive halos $\gtrsim10^{14.5}~M_\odot$. Our
estimates could be useful to calibrate independent cluster mass estimates from
weak lensing, SZ, and X-ray studies. Our method can be applied to any list of
galaxy clusters or groups in both present and forthcoming surveys such as SDSS,
CFHTLS, DES, LSST, and Euclid.


title: Plastic response and correlations in athermally sheared amorphous solids

abstract:
  The onset of irreversible deformation in low-temperature amorphous solids is
due to the accumulation of elementary events, consisting of spacially and
temporally localized atomic rearrangements involving only a few tens of atoms.
Recently, numerical and experimental work addressed the issue of
spatio-temporal correlations between these plastic events. Here, we provide
further insight into these correlations by investigating, via molecular
dynamics (MD) simulations, the plastic response of a two-dimensional amorphous
solid to artificially triggered local shear transformations. We show that while
the plastic response is virtually absent in as-quenched configurations, it
becomes apparent if a shear strain was previously imposed on the system.
Plastic response has a four-fold symmetry which is characteristic of the shear
stress redistribution following the local transformation. At high shear rate we
report evidence for a fluctuation-dissipation relation, connecting plastic
response and correlation, which seems to break down if lower shear rates are
considered.


title: Vortex Lattices in the Bose-Fermi Superfluid Mixture

abstract:
  In this letter we show that the vortex lattice structure in the Bose-Fermi
superfluid mixture can undergo a sequence of structure transitions when the
Fermi superfluid is tuned from the BCS regime to the BEC regime. This is due to
different vortex core structure of the Fermi superfluid in the BCS regime and
in the BEC regime. In the former the vortex core is nearly filled, while the
density at the vortex core gradually decreases until it empties out at the BEC
regime. Therefore, with the density-density interaction between the Bose and
the Fermi superfluids, the two sets of vortex lattices interact stronger in the
BEC regime that yields the structure transition of vortex lattices. In view of
recent realization of this superfluid mixture and vortices therein, our
theoretical predication can be verified experimentally in near future.


title:
Simulations of 3D-Si sensors for the innermost layer of the ATLAS pixel
  upgrade

abstract:
  The LHC is expected to reach luminosities up to 3000fb-1 and the innermost
layer of the ATLAS upgrade plans to cope with higher occupancy and to decrease
the pixel size. 3D-Si sensors are a good candidate for the innermost layer of
the ATLAS pixel upgrade since they exhibit good performance under high fluences
and the new designs will have smaller pixel size to fulfill the electronics
expectations. This paper reports TCAD simulations of the 3D-Si sensors designed
at IMB-CNM with non passing-through columns that are being fabricated for the
next innermost layer of the ATLAS pixel upgrade, shows the charge collection
response before and after irradiation, and the response of 3D-Si sensors
located at large $\eta$ angles.


title:
Modeling the shock-cloud interaction in SN 1006: unveiling the origin of
  nonthermal X-ray and gamma-ray emission

abstract:
  The supernova remnant SN 1006 is a source of high-energy particles and its
southwestern limb is interacting with a dense ambient cloud, thus being a
promising region for gamma-ray hadronic emission. We aim at describing the
physics and the nonthermal emission associated with the shock-cloud interaction
to derive the physical parameters of the cloud (poorly constrained by the data
analysis), to ascertain the origin of the observed spatial variations in the
spectral properties of the X-ray synchrotron emission, and to predict spectral
and morphological features of the resulting gamma-ray emission. We performed
3-D magnetohydrodynamic simulations modeling the evolution of SN 1006 and its
interaction with the ambient cloud, and explored different model setups. By
applying the REMLIGHT code on the model results, we synthesized the synchrotron
X-ray emission, and compared it with actual observations, to constrain the
parameters of the model. We also synthesized the leptonic and hadronic
gamma-ray emission from the models, deriving constraints on the energy content
of the hadrons accelerated at the southwestern limb. We found that the impact
of the SN 1006 shock front with a uniform cloud with density 0.5 cm^-3 can
explain the observed morphology, the azimuthal variations of the cutoff
frequency of the X-ray synchrotron emission, and the shock proper motion in the
interaction region. Our results show that the current upper limit for the total
hadronic energy in the southwestern limb is 2.5e49 erg.


title:
Variational Geometric Approach to Generalized Differential and Fenchel
  Conjugate Calculi in Convex Analysis

abstract:
  This paper develops a geometric approach of variational analysis for the case
of convex objects considered in locally convex topological spaces and also in
Banach space settings. Besides deriving in this way new results of convex
calculus, we present an overview of some known achievements with their unified
and simplified proofs based on the developed geometric variational schemes.


title: Device-independence for two-party cryptography and position verification

abstract:
  Quantum communication has demonstrated its usefulness for quantum
cryptography far beyond quantum key distribution. One domain is two-party
cryptography, whose goal is to allow two parties who may not trust each other
to solve joint tasks. Another interesting application is position-based
cryptography whose goal is to use the geographical location of an entity as its
only identifying credential. Unfortunately, security of these protocols is not
possible against an all powerful adversary. However, if we impose some
realistic physical constraints on the adversary, there exist protocols for
which security can be proven, but these so far relied on the knowledge of the
quantum operations performed during the protocols. In this work we give
device-independent security proofs of two-party cryptography and Position
Verification for memoryless devices under different physical constraints on the
adversary. We assess the quality of the devices by observing a Bell violation
and we show that security can be attained for any violation of the
Clauser-Holt-Shimony-Horne inequality.


title: Comparison of OFDM and Single-Carrier for Large-Scale Antenna Systems

abstract:
  Large-scale antenna (LSA) or massive multiple-input multiple-output (MIMO)
has gained a lot of attention due to its potential to significantly improve
system throughput. As a natural evolution from traditional MIMO-orthogonal
frequency division multiplexing (OFDM), LSA has been combined with OFDM to deal
with frequency selectivity of wireless channels in most existing works. As an
alternative approach, single-carrier (SC) has also been proposed for LSA
systems due to its low implementation complexity. In this article, a
comprehensive comparison between LSA-OFDM and LSA-SC is presented, which is of
interest to the waveform design for the next generation wireless systems.


title: On quadratic polynomial mappings $f: \Bbb C^2 \to \Bbb C^2$

abstract:
  We show that up to linear equivalence, there is only finitely many polynomial
quadratic mappings $f:\Bbb C^2\to\Bbb C^2$ and $f:\Bbb R^2\to \Bbb R^2.$ We
list all possibilities.


title: Reweighting QCD matrix-element and parton-shower calculations

abstract:
  We present the implementation and validation of the techniques used to
efficiently evaluate parametric and perturbative theoretical uncertainties in
matrix-element plus parton-shower simulations within the Sherpa event-generator
framework. By tracing the full $\alpha_s$ and PDF dependences, including the
parton-shower component, as well as the fixed-order scale uncertainties, we
compute variational event weights on-the-fly, thereby greatly reducing the
computational costs to obtain theoretical-uncertainty estimates.


title:
Dual and chiral objects for optical activity in general scattering
  directions

abstract:
  Optically active artificial structures have attracted tremendous research
attention. Such structures must meet two requirements: Lack of spatial
inversion symmetries and, a condition usually not explicitly considered, the
structure shall preserve the helicity of light, which implies that there must
be a vanishing coupling between the states of opposite polarization handedness
among incident and scattered plane waves. Here, we put forward and demonstrate
that a unit cell made from chiraly arranged electromagnetically dual scatterers
serves exactly this purpose. We prove this by demonstrating optical activity of
such unit cell in general scattering directions.


title:
Experimental evidence of independence of nuclear de-channeling length on
  the particle charge sign

abstract:
  Under coherent interactions, particles undergo correlated collisions with the
crystal lattice and their motion result in confinement in the fields of atomic
planes, i.e. particle channeling. Other than coherently interacting with the
lattice, particles also suffer incoherent interactions with individual nuclei
and may leave their bounded motion, i.e., they de-channel. This latter is the
main limiting factor for applications of coherent interactions in
crystal-assisted particle steering. We experimentally investigated the nature
of dechanneling of 120 GeV/c $e^{-}$ and $e^{+}$ in a bent silicon crystal at
H4-SPS external line at CERN. We found out that while channeling efficiency
differs significantly for $e^{-}$ ($2\pm2$ $\%$) and $e^{+}$ ($54\pm2$ $\%$),
their nuclear dechanneling length is comparable, $(0.6\pm0.1)$ mm for $e^{-}$
and $(0.7\pm0.3)$ mm for $e^{+}$. The experimental proof of the equality of the
nuclear dechanneling length for positrons and electrons is interpreted in terms
of similar dynamics undergone by the channeled particles in the field of nuclei
no matter of their charge.


title:
On the (non-)uniqueness of the Levi-Civita solution in the
  Einstein-Hilbert-Palatini formalism

abstract:
  We study the most general solution for affine connections that are compatible
with the variational principle in the Palatini formalism for the
Einstein-Hilbert action (with possible minimally coupled matter terms). We find
that there is a family of solutions generalising the Levi-Civita connection,
characterised by an arbitrary, non-dynamical vector field ${\cal A}_\mu$. We
discuss the mathematical properties and the physical implications of this
family and argue that, although there is a clear mathematical difference
between these new Palatini connections and the Levi-Civita one, both
unparametrised geodesics and the Einstein equation are shared by all of them.
Moreover, the Palatini connections are characterised precisely by these two
properties, as well as by other properties of its parallel transport. Based on
this, we conclude that physical effects associated to the choice of one or the
other will not be distinguishable, at least not at the level of solutions or
test particle dynamics. We propose a geometrical interpretation for the
existence and unobservability of the new solutions.


title: Stochastic Models of Vesicular Sorting in Cellular Organelles

abstract:
  The proper sorting of membrane components by regulated exchange between
cellular organelles is crucial to intra-cellular organisation. This process
relies on the budding and fusion of transport vesicles, and should be strongly
influenced by stochastic fluctuations considering the relatively small size of
many organelles. We identify the perfect sorting of two membrane components
initially mixed in a single compartment as a first passage process, and we show
that the mean sorting time exhibits two distinct regimes as a function of the
ratio of vesicle fusion to budding rates. Low ratio values lead to fast
sorting, but results in a broad size distribution of sorted compartments
dominated by small entities. High ratio values result in two well defined
sorted compartments but is exponentially slow. Our results suggest an optimal
balance between vesicle budding and fusion for the rapid and efficient sorting
of membrane components, and highlight the importance of stochastic effects for
the steady-state organisation of intra-cellular compartments.


title:
Survey of Nodeless Regular Almost-Everywhere Holomorphic Solutions for
  Exactly Solvable Gauss-Reference Liouville Potentials on the Line I.Subsets
  of Nodeless Jacobi-Seed Solutions Co-Existent with Discrete Energy Spectrum

abstract:
  The paper collates a complete list of nodeless regular almost-everywhere
holomorphic (AEH) solutions for a subset of rational canonical Sturm-Liouville
equations (RCSLEs) exactly quantized on a finite interval by classical Jacobi
polynomials. The subset was constrained by the requirement that the appropriate
Liouville transformation results in the Schrodinger equation on the line. The
common remarkable feature of the selected nodeless solutions co-existent with
the discrete energy spectrum is that they can be used as seed functions for
multi-step 'canonical Liouville-Darboux transformations' (CLDTs) to convert the
Gauss-Reference (GRef) potential (appearing in the resultant Schrodinger
equation) into its isospectral rational SUSY partners conditionally exactly
quantized by the so-called 'Jacobi-Seed' Heine polynomials.


title:
Bayesian analysis of immune response dynamics with sparse time series
  data

abstract:
  In vaccine development, the temporal profiles of relative abundance of
subtypes of immune cells (T-cells) is key to understanding vaccine efficacy.
Complex and expensive experimental studies generate very sparse time series
data on this immune response. Fitting multi-parameter dynamic models of the
immune response dynamics-- central to evaluating mechanisms underlying vaccine
efficacy-- is challenged by data sparsity. The research reported here addresses
this challenge. For HIV/SIV vaccine studies in macaques, we: (a) introduce
novel dynamic models of progression of cellular populations over time with
relevant, time-delayed components reflecting the vaccine response; (b) define
an effective Bayesian model fitting strategy that couples Markov chain Monte
Carlo (MCMC) with Approximate Bayesian Computation (ABC)-- building on the
complementary strengths of the two approaches, neither of which is effective
alone; (c) explore questions of information content in the sparse time series
for each of the model parameters, linking into experimental design and model
simplification for future experiments; and (d) develop, apply and compare the
analysis with samples from a recent HIV/SIV experiment, with novel insights and
conclusions about the progressive response to the vaccine, and how this varies
across subjects.


title:
Figure-eight choreographies of the equal mass three-body problem with
  Lennard-Jones-type potentials

abstract:
  We report on figure-eight choreographic solutions to a system of three
identical particles interacting through a potential of Lennard-Jones type,
$1/r^{12}-1/r^6$ where $r$ is a distance between the particles. By numerical
search, we found there are a multitude of such solutions. A series of them are
close to a figure-eight solutions to a homogeneous system with no $1/r^{12}$
term in the potential. The rest are very different from them and have several
points with large curvatures in their figure-eight orbits, at which particles
are repelled. Here figure-eight choreographies are the periodic motion whose
shape is symmetric in both horizontal and vertical axis, starting with an
isosceles triangle configuration and going back to an isosceles triangle
configuration with opposite direction through Euler configuration. Thus the
lobe of this figure-eight may be complex shape and needs not to be convex.


title:
A Dissipative Systems Theory for FDTD with Application to Stability
  Analysis and Subgridding

abstract:
  This paper establishes a far-reaching connection between the
Finite-Difference Time-Domain method (FDTD) and the theory of dissipative
systems. The FDTD equations for a rectangular region are written as a dynamical
system having the magnetic and electric fields on the boundary as inputs and
outputs. Suitable expressions for the energy stored in the region and the
energy absorbed from the boundaries are introduced, and used to show that the
FDTD system is dissipative under a generalized Courant-Friedrichs-Lewy
condition. Based on the concept of dissipation, a powerful theoretical
framework to investigate the stability of FDTD methods is devised. The new
method makes FDTD stability proofs simpler, more intuitive, and modular.
Stability conditions can indeed be given on the individual components (e.g.
boundary conditions, meshes, embedded models) instead of the whole coupled
setup. As an example of application, we derive a new subgridding method with
material traverse, arbitrary grid refinement, and guaranteed stability. The
method is easy to implement and has a straightforward stability proof.
Numerical results confirm its stability, low reflections, and ability to handle
material traverse.


title: A user's guide to cloning systems

abstract:
  In joint work of the author with Stefan Witzel, a procedure was developed for
building new examples of groups in the extended family of R. Thompson's groups,
using what we termed \emph{cloning systems}. These new Thompson-like groups can
be thought of as limits of families of groups, though unlike other limiting
processes, e.g., direct limits, these tend to be well behaved with respect to
finiteness properties. In this expository note, we distill the crucial parts of
that 50-page paper into a more digestible form, for those curious to understand
the construction but less curious about the gritty details. We also give one
new example, of a cloning system involving signed symmetric groups.


title: Beyond Linear Fields: the Lie-Taylor Expansion

abstract:
  The work extends the linear fields' solution of compressible nonlinear
magnetohydrodynamics~(MHD) to the case where the magnetic field depends on
superlinear powers of position vector, usually but not always, expressed in
Cartesian components. Implications of the resulting Lie-Taylor series expansion
for physical applicability of the Dolzhansky-Kirchhoff~(D-K) equations are
found to be positive. It is demonstrated how resistivity may be included in the
D-K model. Arguments are put forward that the D-K equations may be regarded as
illustrating properties of nonlinear MHD in the same sense that the Lorenz
equations inform about the onset of convective turbulence. It is suggested that
the Lie-Taylor series approach may lead to valuable insights into other fluid
models.


title: Complexity Bounds of Constant-Space Quantum Computation

abstract:
  We realize constant-space quantum computation by measure-many two-way quantum
finite automata and evaluate their language recognition power by analyzing
patterns of their exotic behaviors and by exploring their structural
properties. In particular, we show that, when the automata halt "in finite
steps" along all computation paths, they must terminate in worst-case liner
time. In the bounded-error probability case, the acceptance of the automata
depends only on the computation paths that terminate within exponentially many
steps even if not all computation paths may terminate. We also present a
classical simulation of those automata on two-way multi-head probabilistic
finite automata with cut points. Moreover, we discuss how the recognition power
of the automata varies as the automata's acceptance criteria change to error
free, one-sided error, bounded error, and unbounded error by comparing the
complexity of their computational powers. We further note that, with the use of
arbitrary complex transition amplitudes, two-way unbounded-error quantum finite
automata and two-way bounded-error 2-head quantum finite automata can recognize
certain non-recursive languages, whereas two-way error-free quantum finite
automata recognize only recursive languages.


title:
Exciting Reflectionless Unidirectional Edge Modes in a Reciprocal
  Photonic Topological Insulator Medium

abstract:
  Photonic topological insulators are an interesting class of materials whose
photonic band structure can have a bandgap in the bulk while supporting
topologically protected unidirectional edge modes. Recent studies [1-6] on
bianisotropic metamaterials that emulate the electronic quantum spin Hall
effect using its electromagnetic analog are examples of such systems with
relatively simple and elegant design. In this paper, we present a rotating
magnetic dipole antenna, composed of two perpendicularly oriented coils, that
can efficiently excite the unidirectional topologically protected surface waves
in the bianisotropic metawaveguide (BMW) structure recently realized by Ma, et
al. [1], despite the fact that the BMW medium does not break time-reversal
invariance. In addition to achieving high directivity, the antenna can be tuned
continuously to excite reflectionless edge modes to the two opposite directions
with various amplitude ratios. We demonstrate its performance through
experiment and compare to simulation results.


title: Robust Massively Parallel Sorting

abstract:
  We investigate distributed memory parallel sorting algorithms that scale to
the largest available machines and are robust with respect to input size and
distribution of the input elements. The main outcome is that four sorting
algorithms cover the entire range of possible input sizes. For three algorithms
we devise new low overhead mechanisms to make them robust with respect to
duplicate keys and skewed input distributions. One of these, designed for
medium sized inputs, is a new variant of quicksort with fast high-quality pivot
selection.
  At the same time asymptotic analysis provides performance guarantees and
guides the selection and configuration of the algorithms. We validate these
hypotheses using extensive experiments on 7 algorithms, 10 input distributions,
up to 262144 cores, and varying input sizes over 9 orders of magnitude. For
difficult input distributions, our algorithms are the only ones that work at
all. For all but the largest input sizes, we are the first to perform
experiments on such large machines at all and our algorithms significantly
outperform the ones one would conventionally have considered.


title: $D^*$ $\Xi N$ bound state in strange three-body systems

abstract:
  The recent update of the strangeness $-2$ ESC08c Nijmegen potential
incorporating the NAGARA and KISO events predicts a $\Xi N$ bound state, $D^*$,
in the $^3S_1 (I=1)$ channel. We study if the existence of this two-body bound
state could give rise to stable three-body systems. For this purpose we solve
the bound state problem of three-body systems where the $\Xi N$ state is merged
with $N$'s, $\Lambda$'s, $\Sigma's$ or $\Xi$'s, making use of the most recent
updates of the two-body ESC08c Nijmegen potentials. We found that there appear
stable states in the $\Xi NN$ and $\Xi \Xi N$ systems, the $\Xi \Lambda N$ and
$\Xi \Sigma N$ systems being unbound.


title:
Degree-correlation, robustness, and vulnerability in finite scale-free
  networks

abstract:
  Many naturally occurring networks have a power-law degree distribution as
well as a non-zero degree correlation. Despite this, most studies analyzing the
robustness to random node-deletion and vulnerability to targeted node-deletion
have concentrated only on power-law degree distribution and ignored degree
correlation. This study looks specifically at the effect degree-correlation has
on robustness and vulnerability in scale-free networks. Our results confirm
Newman's finding that positive degree-correlation increases robustness and
decreases vulnerability. However, we found that networks with positive
degree-correlation are more vulnerable to random node-deletion than to targeted
deletion methods that utilize knowledge of initial node-degree only. Targeted
deletion sufficiently alters the topology of the network to render this method
less effective than uniform random methods unless changes in topology are
accounted for. This result indicates the importance of degree correlation in
certain network applications.


title: A note on the scaling limits of random P\'olya trees

abstract:
  Panagiotou and Stufler (arXiv:1502.07180v2) recently proved one important
fact on their way to establish the scaling limits of random P\'{o}lya trees: a
uniform random P\'{o}lya tree of size $n$ consists of a conditioned critical
Galton-Watson tree $C_n$ and many small forests, where with probability tending
to one as $n$ tends to infinity, any forest $F_n(v)$, that is attached to a
node $v$ in $C_n$, is maximally of size $\vert F_n(v)\vert=O(\log n)$. Their
proof used the framework of a Boltzmann sampler and deviation inequalities.
  In this paper, first, we employ a unified framework in analytic combinatorics
to prove this fact with additional improvements on the bound of $\vert
F_n(v)\vert$, namely $\vert F_n(v)\vert=\Theta(\log n)$. Second, we give a
combinatorial interpretation of the rational weights of these forests and the
defining substitution process in terms of automorphisms associated to a given
P\'{o}lya tree. Finally, we derive the limit probability that for a random node
$v$ the attached forest $F_n(v)$ is of a given size.


title:
Time-dependent global sensitivity analysis with active subspaces for a
  lithium ion battery model

abstract:
  Renewable energy researchers use computer simulation to aid the design of
lithium ion storage devices. The underlying models contain several physical
input parameters that affect model predictions. Effective design and analysis
must understand the sensitivity of model predictions to changes in model
parameters, but global sensitivity analyses become increasingly challenging as
the number of input parameters increases. Active subspaces are part of an
emerging set of tools for discovering and exploiting low-dimensional structures
in the map from high-dimensional inputs to model outputs. We extend linear and
quadratic model-based heuristic for active sub- space discovery to
time-dependent processes and apply the resulting technique to a lithium ion
battery model. The results reveal low-dimensional structure and sensitivity
metrics that a designer may exploit to study the relationship between
parameters and predictions.


title:
Characterising the physical and chemical properties of a young Class 0
  protostellar core embedded in the Orion B9 filament

abstract:
  The present study aims to characterise the physical and chemical properties
of the protostellar core Orion B9-SMM3. The APEX telescope was used to perform
a follow-up molecular line survey of SMM3. The following species were
identified from the frequency range 218.2-222.2 GHz: $^{13}$CO, C$^{18}$O, SO,
para-H$_2$CO, and E$_1$-type CH$_3$OH. The on-the-fly mapping observations at
215.1-219.1 GHz revealed that SMM3 is associated with a dense gas core as
traced by DCO$^+$ and p-H$_2$CO. Altogether three different p-H$_2$CO
transitions were detected with clearly broadened linewidths (8.2-11 km s$^{-1}$
in FWHM). The derived p-H$_2$CO rotational temperature, $64\pm15$ K, indicates
the presence of warm gas. We also detected a narrow p-H$_2$CO line (FWHM=0.42
km s$^{-1}$) at the systemic velocity. The p-H$_2$CO abundance for the broad
component appears to be enhanced by two orders of magnitude with respect to the
narrow line value ($\sim3\times10^{-9}$ versus $\sim2\times10^{-11}$). The
detected methanol line shows a linewidth similar to those of the broad
p-H$_2$CO lines, which indicates their coexistence. The CO isotopologue data
suggest that the CO depletion factor decreases from $\sim27\pm2$ towards the
core centre to a value of $\sim8\pm1$ towards the core edge. In the latter
position, the N$_2$D$^+$/N$_2$H$^+$ ratio is revised down to $0.14\pm0.06$. The
origin of the subfragments inside the SMM3 core we found previously can be
understood in terms of the Jeans instability if non-thermal motions are taken
into account. The estimated fragmentation timescale, and the derived chemical
abundances suggest that SMM3 is a few times $10^5$ yr old, in good agreement
with its Class 0 classification inferred from the spectral energy distribution
analysis. The broad p-H$_2$CO and CH$_3$OH lines, and the associated warm gas
provide the first clear evidence of a molecular outflow driven by SMM3.


title:
Search for bottom squark pair production in proton--proton collisions at
  $\sqrt{s}=$13 TeV with the ATLAS detector

abstract:
  The result of a search for pair production of the supersymmetric partner of
the Standard Model bottom quark ($\tilde{b}_1$) is reported. The search uses
3.2 fb$^{-1}$ of $pp$ collisions at $\sqrt{s}=$13 TeV collected by the ATLAS
experiment at the Large Hadron Collider in 2015. Bottom squarks are searched
for in events containing large missing transverse momentum and exactly two jets
identified as originating from $b$-quarks. No excess above the expected
Standard Model background yield is observed. Exclusion limits at 95% confidence
level on the mass of the bottom squark are derived in phenomenological
supersymmetric $R$-parity-conserving models in which the $\tilde{b}_1$ is the
lightest squark and is assumed to decay exclusively via $\tilde{b}_1
\rightarrow b \tilde{\chi}_1^0$, where $\tilde{\chi}_1^0$ is the lightest
neutralino. The limits significantly extend previous results; bottom squark
masses up to 800 (840) GeV are excluded for the $\tilde{\chi}_1^0$ mass below
360 (100) GeV whilst differences in mass above 100 GeV between the
$\tilde{b}_1$ and the $\tilde{\chi}_1^0$ are excluded up to a $\tilde{b}_1$
mass of 500 GeV.


title: Measure Algebras on Homogeneous Spaces

abstract:
  For a locally compact group $G$ and a compact subgroup $H$, we show that the
Banach space $M(G/H)$ may be considered as a quotient space of $M(G)$. Also, we
define a convolution on $M(G/H)$ which makes it into a Banach algebra. It may
be identified with a closed subalgebra of the involutive Banach algebra $M(G)$,
and there is no involution on $M(G/H)$ compatible with this identification
unless $H$ is a normal subgroup of $G$. In other words, $M(G/H)$ is a
$*$-Banach subalgebra of $M(G)$ only if $H$ is a normal subgroup of $G$. As
well, it is a unital Banach algebra just when $H$ is a normal subgroup.
Furthermore, when $G/H$ is attached to a strongly quasi-invariant measure,
$L^1(G/H)$ is a Banach subspace of $M(G/H)$. Using the restriction of the
convolution on $M(G/H)$, we obtain a Banach algebra $L^1(G/H)$, which may be
considered as a Banach subalgebra of $L^1(G)$, with a right approximate
identity. It has no involution and no left approximate identity except for a
normal subgroup $H$. Consequently, the Banach algebra $L^1(G/H)$ is amenable if
and only if $H$ is a normal subgroup and $G$ is amenable.


title:
Control of Spin Helix Symmetry in Semiconductor Quantum Wells by Crystal
  Orientation

abstract:
  We investigate the possibility of spin-preserving symmetries due to the
interplay of Rashba and Dresselhaus spin-orbit coupling in n-doped zinc-blende
semiconductor quantum wells of general crystal orientation. It is shown that a
conserved spin operator can be realized if and only if at least two
growth-direction Miller indices agree in modulus. The according spin-orbit
field has in general both in-plane and out-of-plane components and is always
perpendicular to the shift vector of the corresponding persistent spin helix.
We also analyze higher-order effects arising from the Dresselhaus term, and the
impact of our results on weak (anti)localization corrections.


title: Mass density of the Earth from a Gravito-Electro-Magnetic 5D vacuum

abstract:
  We calculate the mass density of the Earth using a Gravito-Electro-Magnetic
theory on an extended 5D Schwarzschild-de Sitter metric, in which we define the
vacuum. Our results are in very good agreement with that of the
Dziewonski-Anderson model.


title:
Performance of dynamical decoupling in bosonic environments and under
  pulse-timing fluctuations

abstract:
  We study the suppression of qubit dephasing through Uhrig dynamical
decoupling (UDD) in nontrivial environments modeled within the spin-boson
formalism. In particular, we address the case of (i) a qubit coupled to a
bosonic bath with power-law spectral density, and (ii) a qubit coupled to a
single harmonic oscillator that dissipates energy into a bosonic bath, which
embodies an example of a structured bath for the qubit. We then model the
influence of random time jitter in the UDD protocol by sorting
pulse-application times from Gaussian distributions centered at appropriate
values dictated by the optimal protocol. In case (i) we find that, when few
pulses are applied and a sharp cutoff is considered, longer coherence times and
robust UDD performances (against random timing errors) are achieved for a
super-Ohmic bath. On the other hand, when an exponential cutoff is considered a
super-Ohmic bath is undesirable. In case (ii) the best scenario is obtained for
an overdamped harmonic motion. Our study provides relevant information for the
implementation of optimized schemes for the protection of quantum states from
decoherence.


title: "Show me the cup": Reference with Continuous Representations

abstract:
  One of the most basic functions of language is to refer to objects in a
shared scene. Modeling reference with continuous representations is challenging
because it requires individuation, i.e., tracking and distinguishing an
arbitrary number of referents. We introduce a neural network model that, given
a definite description and a set of objects represented by natural images,
points to the intended object if the expression has a unique referent, or
indicates a failure, if it does not. The model, directly trained on reference
acts, is competitive with a pipeline manually engineered to perform the same
task, both when referents are purely visual, and when they are characterized by
a combination of visual and linguistic properties.


title: Could Segue 1 be a destroyed star cluster? - a dynamical perspective

abstract:
  We attempt to find a progenitor for the ultra-faint object Segue 1 under the
assumption that it formed as a dark matter free star cluster in the past. We
look for orbits, using the elongation of Segue 1 on the sky as a tracer of its
path. Those orbits are followed backwards in time to find the starting points
of our N-body simulations. The successful orbit, with which we can reproduce
Segue 1 has a proper motion of mu_alpha = -0.19 mas/yr and mu_delta = -1.9
mas/yr, placing Segue 1 near its apo-galacticon today. Our best fitting model
has an initial mass of 6224 Msun and an initial scale-length of 5.75 pc.


title:
Interface propagation in fiber bundles: Local, mean-field and
  intermediate range-dependent statistics

abstract:
  The fiber bundle model is essentially an array of elements that break when
sufficient load is applied on them. With a local loading mechanism, this can
serve as a model for a one-dimensional interface separating the broken and
unbroken parts of a solid in mode-I fracture. The interface can propagate
through the system depending on the loading rate and disorder present in the
failure thresholds of the fibers. In the presence of a quasi-static drive, the
intermittent dynamics of the interface mimic front propagation in disordered
media. Such situations appear in diverse physical systems such as mode-I crack
propagation, domain wall dynamics in magnets, charge density waves, contact
line in wetting etc. We study the effect of the range of interaction, i.e. the
neighborhood of the interface affected following a local perturbation, on the
statistics of the intermittent dynamics of the front. There exists a crossover
from local to global behavior as the range of interaction grows and a
continuously varying `universality' in the intermediate range. This means that
the interaction range is a relevant parameter of any resulting physics. This is
particularly relevant in view of the fact that there is a scatter in the
experimental observations of the exponents, in even idealized experiments on
fracture fronts, and also a possibility in changing the interaction range in
real samples.


title:
Comment on "Frustration and Multicriticality in the Antiferromagnetic
  Spin-1 Chain"

abstract:
  The phase diagram of the spin-1 chain with bilinear-biquadratic and
next-nearest neighbor inter- actions, recently investigated by Pixley, Shashi
and Nevidomskyy [Phys. Rev. B 90, 214426 (2014)], has been revisited in the
light of results we have recently obtained on a similar model. Combining
extensive Density Matrix Renormalization Group (DMRG) simulations with
conformal-field theory arguments, we confirm the presence of the three phases
identified by Pixley et al, a Haldane phase, a next-nearest neighbor (NNN)
Haldane phase, and a dimerized phase, but we come to significantly different
conclusions regarding the nature of the phase transitions to the dimerized
phase: i) We provide numerical evidence of a continuous Ising transition
between the NNN-Haldane phase and the dimerized phase; ii) We show that the
tri-critical end point, where the continuous transition between the Haldane
phase and the dimerized phase turns into a first order transition, is distinct
from the triple point where the three phases meet; iii) Finally, we demonstrate
that the tri-critical end point is in the same Wess-Zumino-Witten (WZW) SU(2)
level 2 universality class as the continuous transition line that ends at this
point


title: Simulating generic spin-boson models with matrix product states

abstract:
  The global coupling of few-level quantum systems ("spins") to a discrete set
of bosonic modes is a key ingredient for many applications in quantum science,
including large-scale entanglement generation, quantum simulation of the
dynamics of long-range interacting spin models, and hybrid platforms for force
and spin sensing. We present a general numerical framework for treating the
out-of-equilibrium dynamics of such models based on matrix product states. Our
approach applies for generic spin-boson systems: it treats any spatial and
operator dependence of the two-body spin-boson coupling and places no
restrictions on relative energy scales. We show that the full counting
statistics of collective spin measurements and infidelity of quantum simulation
due to spin-boson entanglement, both of which are difficult to obtain by other
techniques, are readily calculable in our approach. We benchmark our method
using a recently developed exact solution for a particular spin-boson coupling
relevant to trapped ion quantum simulators. Finally, we show how decoherence
can be incorporated within our framework using the method of quantum
trajectories, and study the dynamics of an open-system spin-boson model with
spatially non-uniform spin-boson coupling relevant for trapped atomic ion
crystals in the presence of molecular ion impurities.


title: The time evolution of gaps in tidal streams

abstract:
  We model the time evolution of gaps in tidal streams caused by the impact of
a dark matter subhalo, while both orbit a spherical gravitational potential. To
this end, we make use of the simple behaviour of orbits in action-angle space.
A gap effectively results from the divergence of two nearby orbits whose
initial phase-space separation is, for very cold thin streams, largely given by
the impulse induced by the subhalo. We find that in a spherical potential the
size of a gap increases linearly with time for sufficiently long timescales. We
have derived an analytic expression that shows how the growth rate depends on
the mass of the perturbing subhalo, its scale and its relative velocity with
respect to the stream. We have verified these scalings using N-body simulations
and find excellent agreement. For example, a subhalo of mass 10^8 Msun directly
impacting a very cold thin stream on an inclined orbit can induce a gap that
may reach a size of several tens of kpc after a few Gyr. The gap size
fluctuates importantly with phase on the orbit, and it is largest close to
pericentre. This indicates that it may not be fully straightforward to invert
the spectrum of gaps present in a stream to recover the mass spectrum of the
subhalos.


title:
Assessment of Models of Galactic Thermal Dust Emission Using COBE/FIRAS
  and COBE/DIRBE Observations

abstract:
  Accurate modeling of the spectrum of thermal dust emission at millimeter
wavelengths is important for improving the accuracy of foreground subtraction
for CMB measurements, for improving the accuracy with which the contributions
of different foreground emission components can be determined, and for
improving our understanding of dust composition and dust physics. We fit four
models of dust emission to high Galactic latitude COBE/FIRAS and COBE/DIRBE
observations from 3 millimeters to 100 microns and compare the quality of the
fits. We consider the two-level systems model because it provides a physically
motivated explanation for the observed long wavelength flattening of the dust
spectrum and the anticorrelation between emissivity index and dust temperature.
We consider the model of Finkbeiner, Davis, and Schlegel because it has been
widely used for CMB studies, and the generalized version of this model recently
applied to Planck data by Meisner and Finkbeiner. For comparison we have also
fit a phenomenological model consisting of the sum of two graybody components.
We find that the two-graybody model gives the best fit and the FDS model gives
a significantly poorer fit than the other models. The Meisner and Finkbeiner
model and the two-level systems model remain viable for use in Galactic
foreground subtraction, but the FIRAS data do not have sufficient
signal-to-noise ratio to provide a strong test of the predicted spectrum at
millimeter wavelengths.


title: Nonlocal Infrared Modifications of Gravity. A Review

abstract:
  We review an approach developed in the last few years by our group in which
GR is modified in the infrared, at an effective level, by nonlocal terms
associated to a mass scale. We begin by recalling the notion of quantum
effective action and its associated nonlocalities, illustrating some of their
features with the anomaly-induced effective actions in $D=2$ and $D=4$. We
examine conceptual issues of nonlocal theories such as causality, degrees of
freedoms and ghosts, stressing the importance of the fact that these
nonlocalities only emerge at the effective level. We discuss a particular class
of nonlocal theories where the nonlocal operator is associated to a mass scale,
and we show that they perform very well in the comparison with cosmological
observations, to the extent that they fit CMB, supernovae, BAO and structure
formation data at a level fully competitive with $\Lambda$CDM, with the same
number of free parameters. We explore some extensions of these `minimal'
models, and we finally discuss some directions of investigation for deriving
the required effective nonlocality from a fundamental local QFT.


title:
Phenomenology of SU(5) low-energy realizations: the diphoton excess and
  Higgs flavor violation

abstract:
  We discuss different $\rm SU(5)$ low-energy realizations and illustrate their
use with the diphoton excess and Higgs flavor violation, which require new
physics at the TeV scale. In particular, we study two scenarios for a $750$ GeV
resonance: in the first one the resonance belongs to the adjoint of $\rm
SU(5)$, being either an $\rm SU(2)_L$ singlet or a triplet, while in the second
case the signal is due to the CP-even and CP-odd states of a new $\rm SU(2)_L$
Higgs doublet belonging to a ${\bf 45}_H$ or a ${\bf 70}_H$ representations,
giving rise to a two-Higgs doublet model at low energies. We study the
fine-tuning needed for the desired members of the multiplets to be light
enough, while having the rest at the GUT scale. In these scenarios, the
production and decay into photons of the new resonance are mediated by the
leptoquarks (LQ) present in these large $\rm SU(5)$ representations. We analyse
the phenomenology of such scenarios, focusing on the most relevant predictions
that can help to disentangle the different models, like decays into gauge
bosons, Standard Model (SM) fermions and LQs pair production. In the case of
the ${\bf 45}_H$ (the Georgi-Jarlskog model), we also study the possibility to
have Higgs flavor violation. We find that $B_s$ mixing limits (in addition to
$\tau\rightarrow \mu \gamma$) always imply that $\rm{BR}(h\rightarrow
\tau\mu,\,bs)\lesssim 10^{-5}$.


title: Negative stiffness and modulated states in active nematics

abstract:
  We examine the dynamics of a compressible active nematic liquid crystal on a
frictional substrate. When frictional damping dominates over viscous
dissipation, we eliminate flow in favor of active stresses to obtain a minimal
dynamical model for the nematic order parameter, with elastic constants
renormalized by activity. The renormalized elastic constants can become
negative at large activity, leading to the selection of spatially inhomogeneous
patterns via a mechanism analogous to that responsible for modulated phases
arising at an equilibrium Lifshitz point. Tuning activity and the degree of
nematic order in the passive system, we obtain a linear stability phase diagram
that exhibits a nonequilibrium tricritical point where ordered, modulated and
disordered phases meet. Numerical solution of the nonlinear equations yields a
succession of spatial structures of increasing complexity with increasing
activity, including kink walls and active turbulence, as observed in
experiments on microtubule bundles confined at an oil-water interface. Our work
provides a minimal model for an overdamped active nematic that reproduces all
the nonequilibrium structures seen in simulations of the full active nematic
hydrodynamics and provides a framework for understanding some of the mechanisms
for selection of the nonequilibrium patterns in the language of equilibrium
critical phenomena.


title:
Darboux transformation and analytic solutions of the discrete
  \PT-symmetric nonlocal nonlinear Schrodinger equation

abstract:
  In this letter, for the discrete parity-time-symmetric nonlocal nonlinear
Schr\"{o}dinger equation, we construct the Darboux transformation, which
provides an algebraic iterative algorithm to obtain a series of analytic
solutions from a known one. To illustrate, the breathing-soliton solutions,
periodic-wave solutions and localized rational soliton solutions are derived
with the zero and plane-wave solutions as the seeds. The properties of those
solutions are also discussed, and particularly the asymptotic analysis reveals
all possible cases of the interaction between the discrete rational dark and
antidark solitons.


title: Oscillations in epidemic models with spread of awareness

abstract:
  We study ODE models of epidemic spreading with a preventive behavioral
response that is triggered by awareness of the infection. Previous studies of
such models have mostly focused on the impact of the response on the initial
growth of an outbreak and the existence and location of endemic equilibria.
Here we study the question whether this type of response is sufficient to
prevent future flare-ups from low endemic levels if awareness is assumed to
decay over time. In the ODE context, such flare-ups would translate into
sustained oscillations with significant amplitudes.
  Our results show that such oscillations are ruled out in
Susceptible-Aware-Infectious-Susceptible models with a single compartment of
aware hosts, but can occur if we consider two distinct compartments of aware
hosts who differ in their willingness to alert other susceptible hosts.


title:
Ultrafast molecular dynamics of dissociative ionization in OCS probed by
  soft X-ray synchrotron radiation

abstract:
  Soft X-rays (90-173 eV) from the 3rd generation Canadian Light Source have
been used in conjunction with a multi coincidence time and position sensitive
detection apparatus to observe the dissociative ionization of OCS. By varying
the X-ray energy we can compare dynamics from direct and Auger ionization
processes, and access ionization channels which result in two or three body
breakup, from 2+ to 4+ ionization states. We make several new observations for
the 3+ state such as kinetic energy release limited by photon energy, and using
Dalitz plots we can see evidence of timescale effects between the direct and
Auger ionization process for the first time. Finally, using Dalitz plots for
OCS$^{4+}$ we observe for the first time that breakup involving an O$^{2+}$ ion
can only proceed from out of equilibrium nuclear arrangement for S(2p) Auger
ionization.


title: Robust Tverberg and colorful Carath\'eodory results via random choice

abstract:
  We use the probabilistic method to obtain versions of the colorful
Carath\'eodory theorem and Tverberg's theorem with tolerance.
  In particular, we give bounds for the smallest integer $N=N(t,d,r)$ such that
for any $N$ points in $R^d$, there is a partition of them into $r$ parts for
which the following condition holds: after removing any $t$ points from the
set, the convex hulls of what is left in each part intersect.
  We prove the bound $N=rt+O(\sqrt{t})$ for fixed $r,d$ which is polynomial in
each parameters. Our bounds extend to colorful versions of Tverberg's theorem,
as well as Reay-type variations of this theorem.


title:
Phase diagram and self-organising dynamics in a strongly-interacting
  thermal Rydberg ensemble

abstract:
  Abstract Far-from equilibrium dynamics that lead to self-organization are
highly relevant to complex dynamical systems not only in physics, but also in
life-, earth-, and social sciences. It is challenging however to find systems
with sufficiently controllable parameters that allow quantitatively modelling
of emergent properties. Here, we study a non-equilibrium phase transition and
observe signatures of self-organized criticality in a dilute thermal vapour of
atoms optically excited to strongly interacting Rydberg states.
Electromagnetically induced transparency (EIT) provides excellent control over
the population dynamics and enables high-resolution probing of the
driven-dissipative dynamics, which also exhibits phase bistability. Increased
sensitivity compared to previous work allows us to reconstruct the complete
phase diagram including in the vicinity of the critical point. We observe that
interaction-induced energy shifts and enhanced decay only occur in one of the
phases above a critical Rydberg population. This limits the application of
generic mean-field models, however a modified, threshold-dependent approach is
in qualitative agreement with experimental data. Near threshold, we observe
self-organized dynamics in the form of population jumps that return the density
to a critical value.


title:
Reply to comment by K.A. Duderstadt et al. on "Atmospheric ionization by
  high-fluence, hard spectrum solar proton events and their probable appearance
  in the ice core archive"

abstract:
  Duderstadt et al. [2016b] comment that the Melott et al. [2016] study of
nitrate formation by solar proton events (SPEs) and comparison with the ice
core archive is "fundamentally flawed," because it does not include
pre-existing HNO3 in the stratosphere. We show that they exaggerate both the
enhancement predicted by our findings and pre-industrial HNO3 levels in their
model, and fail to prove this assertion. Our feasibility study matched expected
SPE nitrate production with ground truth measurements. It is not clear that
their approach is more realistic and absence of a detailed mechanism does not
disprove our results. Models can be no better than the information they are
provided and in this case there continue to be significant unknowns and
uncertainties, especially in the role of polar stratospheric clouds (PSCs) and
possible interactions with cosmic rays that constitute lower boundary
conditions. Duderstadt et al. [2014; 2016a] used incomplete, poorly-constrained
and incorrect initial and boundary conditions, and they continue to advocate on
the basis of uncertain results. Meanwhile, Smart et al. [2014] identified a
series of ice core nitrate spikes that have since been confirmed in 10Be by
McCracken and Beer [2015]. Melott et al. [2016] computationally reproduced the
ionization profile of the only major balloon measurements to date. We show that
our calculated nitrate enhancement is consistent with measured results, given
current levels of uncertainty, and that extreme SPEs can potentially produce
occasional nitrate spikes with hundreds of percent increases. Instead of
repeating old arguments to dismiss nitrates as proxies of SPEs, it is past time
for a dedicated, fine-resolution, multi-parameter, replicate ice core field
campaign to resolve this debate.

categories: physics.ao-ph astro-ph.EP astro-ph.IM astro-ph.SR physics.geo-ph


title: Modeling Industrial ADMET Data with Multitask Networks

abstract:
  Deep learning methods such as multitask neural networks have recently been
applied to ligand-based virtual screening and other drug discovery
applications. Using a set of industrial ADMET datasets, we compare neural
networks to standard baseline models and analyze multitask learning effects
with both random cross-validation and a more relevant temporal validation
scheme. We confirm that multitask learning can provide modest benefits over
single-task models and show that smaller datasets tend to benefit more than
larger datasets from multitask learning. Additionally, we find that adding
massive amounts of side information is not guaranteed to improve performance
relative to simpler multitask learning. Our results emphasize that multitask
effects are highly dataset-dependent, suggesting the use of dataset-specific
models to maximize overall performance.


title: Maurer-Cartan elements in the Lie models of finite simplicial complexes

abstract:
  In a previous work, we have associated a complete differential graded Lie
algebra to any finite simplicial complex in a functorial way. Similarly, we
have also a realization functor from the category of complete differential
graded Lie algebras to the category of simplicial sets. We have already
interpreted the homology of a Lie algebra in terms of homotopy groups of its
realization. In this paper, we begin a dictionary between models and simplicial
complexes by establishing a correspondence between the Deligne groupoid of the
model and the connected components of the finite simplicial complex.


title: Sideband Cooling Beyond the Quantum Limit with Squeezed Light

abstract:
  Quantum fluctuations of the electromagnetic vacuum impose an observable
quantum limit to the lowest temperatures that can be reached with conventional
laser cooling techniques. As laser cooling experiments continue to bring
massive mechanical systems to unprecedented temperatures, this quantum limit
takes on increasingly greater practical importance in the laboratory.
Fortunately, vacuum fluctuations are not immutable, and can be "squeezed"
through the generation of entangled photon pairs. Here we propose and
experimentally demonstrate that squeezed light can be used to sideband cool the
motion of a macroscopic mechanical object below the quantum limit. To do so, we
first cool a microwave cavity optomechanical system with a coherent state of
light to within 15% of this limit. We then cool by more than 2 dB below the
quantum limit using a squeezed microwave field generated by a Josephson
Parametric Amplifier (JPA). From heterodyne spectroscopy of the mechanical
sidebands, we measure a minimum thermal occupancy of 0.19 phonons. With this
novel technique, even low frequency mechanical oscillators can in principle be
cooled arbitrarily close to the motional ground state, enabling the exploration
of quantum physics in larger, more massive systems.


title:
The anisotropic Ising correlations as elliptic integrals: duality and
  differential equations

abstract:
  We present the reduction of the correlation functions of the Ising model on
the anisotropic square lattice to complete elliptic integrals of the first,
second and third kind, the extension of Kramers-Wannier duality to anisotropic
correlation functions, and the linear differential equations for these
anisotropic correlations. More precisely, we show that the anisotropic
correlation functions are homogeneous polynomials of the complete elliptic
integrals of the first, second and third kind. We give the exact dual
transformation matching the correlation functions and the dual correlation
functions. We show that the linear differential operators annihilating the
general two-point correlation functions are factorised in a very simple way, in
operators of decreasing orders.


title: Dynamics of Certain Distal Actions on Spheres

abstract:
  Consider the action of $SL(n+1,\mathbb{R})$ on $\mathbb{S}^n$ arising as the
quotient of the linear action on $\mathbb{R}^{n+1}\setminus\{0\}$. We show that
for a semigroup $\mathfrak{S}$ of $SL(n+1,\mathbb{R})$, the following are
equivalent: $(1)$ $\mathfrak{S}$ acts distally on the unit sphere
$\mathbb{S}^n$. $(2)$ the closure of $\mathfrak{S}$ is a compact group. We also
show that if $\mathfrak{S}$ is closed, the above conditions are equivalent to
the condition that every cyclic subsemigroup of $\mathfrak{S}$ acts distally on
$\mathbb{S}^n$. On the unit circle $\mathbb{S}^1$, we consider the `affine'
actions corresponding to maps in $GL(2,\mathbb{R})$ and discuss the conditions
for the existence of fixed points and periodic points, which in turn imply that
these maps are not distal.


title: Quark masses and strong coupling constant in 2+1 flavor QCD

abstract:
  We present a determination of the strange, charm and bottom quark masses as
well as the strong coupling constant in 2+1 flavor lattice QCD simulations
using highly improved staggered quark action. The ratios of the charm quark
mass to the strange quark mass and the bottom quark mass to the charm quark
mass are obtained from the meson masses calculated on the lattice and found to
be $m_c/m_s=11.871(91)$ and $m_b/m_c=4.528(57)$ in the continuum limit. We also
determine the strong coupling constant and the charm quark mass using the
moments of pseudoscalar charmonium correlators: $\alpha_s(\mu=m_c)=0.3697(85)$
and $m_c(\mu=m_c)=1.267(12)$ GeV. Our result for $\alpha_s$ corresponds to the
determination of the strong coupling constant at the lowest energy scale so far
and is translated to the value $\alpha_s(\mu=M_Z,n_f=5)=0.11622(84)$.


title: A remark on a polynomial mapping from $\C^n$ to $\C^n$

abstract:
  We provide relations of the results obtained in the articles
\cite{ThuyCidinha} and \cite{VuiThang}. Moreover, we provides some examples to
illustrate these relations, using the software {\it Maple} to complete the
complicate calculations of the examples. We give some discussions on these
relations.


title:
Periodic driving control of Raman-induced spin-orbit coupling in
  Bose-Einstein condensates: the heating mechanisms

abstract:
  We focus on a technique recently implemented for controlling the magnitude of
synthetic spin-orbit coupling (SOC) in ultra-cold atoms in the Raman-coupling
scenario. This technique uses a periodic modulation of the Raman-coupling
amplitude to tune the SOC. Specifically, it has been shown that the effect of a
high-frequency sinusoidal modulation of the Raman-laser intensity can be
incorporated into the undriven Hamiltonian via effective parameters, whose
adiabatic variation can then be used to steer the SOC. Here, we characterize
the heating mechanisms that can be relevant to this method. We identify the
main mechanism responsible for the heating observed in the experiments as
basically rooted in driving-induced transfer of population to excited states.
Characteristics of that process determined by the harmonic trapping, the decay
of the excited states, and the technique used for preparing the system are
discussed. Additional heating, rooted in departures from adiabaticity in the
variation of the effective parameters, is also described. Our analytical study
provides some clues that may be useful in the design of strategies for curbing
the effects of heating on the efficiency of the control methods.


title:
Generalized spin squeezing inequalities for particles number with
  quantum fluctuations

abstract:
  Particle number fluctuations, no matter how small, are present in
experimental set-ups. One should rigorously take these fluctuations into
account, especially, for entanglement detection. In this context, we generalize
the spin squeezing inequalities introduced by T\'oth et al. in Phys. Rev. Lett.
99, 250405 (2007). These new inequalities are fulfilled by all separable states
even when the number of particle is not constant, and may present quantum
fluctuations. These inequalities are useful for detecting entanglement in
many-body systems when the super-selection rule does not apply, or when only a
subspace of the total systems Hilbert space is considered. We also define
general dichotomic observables for which we obtain a coordinate independent
form of the generalized spin squeezing inequalities. We give an example where
our generalized coordinate independent spin squeezing inequalities present a
clear advantage over the original ones.


title:
Method for Transferring High-Mobility CVD-Grown Graphene with
  Perfluoropolymers

abstract:
  The transfer of graphene grown by chemical vapor deposition (CVD) using
amorphous polymers represents a widely implemented method for graphene-based
electronic device fabrication. However, the most commonly used polymer,
poly(methyl methacrylate) (PMMA), leaves a residue on the graphene that limits
the mobility. Here we report a method for graphene transfer and patterning that
employs a perfluoropolymer---Hyflon---as a transfer handle and to protect
graphene against contamination from photoresists or other polymers. CVD-grown
graphene transferred this way onto LaAlO$_3$/SrTiO$_3$ heterostructures is
atomically clean, with high mobility (~30,000 cm$^2$V$^{-1}$s$^{-1}$) near the
Dirac point at 2 K and clear, quantized Hall and magneto-resistance. Local
control of the LaAlO$_3$/SrTiO$_3$ interfacial metal-insulator
transition---through the graphene---is preserved with this transfer method. The
use of perfluoropolymers such as Hyflon with CVD-grown graphene and other 2D
materials can readily be implemented with other polymers or photoresists.


title: Puzzling initial conditions in the R_h=ct model

abstract:
  In recent years, some studies have drawn attention to the lack of large-angle
correlations in the observed cosmic microwave background (CMB) temperature
anisotropies with respect to that predicted within the standard $\Lambda$CDM
model. Lately, it has been argued that such a lack of correlations could be
explained in the framework of the so-called $R_h=ct$ model without inflation.
The aim of this work is to study whether there is a mechanism to generate,
through a quantum field theory, the primordial power spectrum presented by
these authors. Specifically, we consider two different scenarios: first, we
assume a scalar field dominating the early Universe in the $R_h=ct$
cosmological model, and second, we deal with the possibility of adding an early
inflationary phase to the mentioned model. During the analysis of the
consistency between the predicted and observed amplitudes of the CMB
temperature anisotropies in both scenarios, we run into deep issues which
indicate that it is not clear how to characterize the primordial quantum
perturbations within the $R_h=ct$ model.


title: The Triangle of Smallest Area Which Circumscribes a Semicircle

abstract:
  An interesting problem that determine a triangle of smallest area which
circumscribes a semicircle is solved. Then a generalized golden right triangles
sequence $T_n$ is obtained, and an interesting construction of the maximum
generalized golden right triangle $T_2$ is also shown.


title:
Theta-RBM: Unfactored Gated Restricted Boltzmann Machine for
  Rotation-Invariant Representations

abstract:
  Learning invariant representations is a critical task in computer vision. In
this paper, we propose the Theta-Restricted Boltzmann Machine ({\theta}-RBM in
short), which builds upon the original RBM formulation and injects the notion
of rotation-invariance during the learning procedure. In contrast to previous
approaches, we do not transform the training set with all possible rotations.
Instead, we rotate the gradient filters when they are computed during the
Contrastive Divergence algorithm. We formulate our model as an unfactored gated
Boltzmann machine, where another input layer is used to modulate the input
visible layer to drive the optimisation procedure. Among our contributions is a
mathematical proof that demonstrates that {\theta}-RBM is able to learn
rotation-invariant features according to a recently proposed invariance
measure. Our method reaches an invariance score of ~90% on mnist-rot dataset,
which is the highest result compared with the baseline methods and the current
state of the art in transformation-invariant feature learning in RBM. Using an
SVM classifier, we also showed that our network learns discriminative features
as well, obtaining ~10% of testing error.


title:
Particle Filter-Based Fault Diagnosis of Nonlinear Systems Using a Dual
  Particle Filter Scheme

abstract:
  In this paper, a dual estimation methodology is developed for both
time-varying parameters and states of a nonlinear stochastic system based on
the Particle Filtering (PF) scheme. Our developed methodology is based on a
concurrent implementation of state and parameter estimation filters as opposed
to using a single filter for simultaneously estimating the augmented states and
parameters. The convergence and stability of our proposed dual estimation
strategy are shown formally to be guaranteed under certain conditions. The
ability of our developed dual estimation method is testified to handle
simultaneously and efficiently the states and time-varying parameters of a
nonlinear system in a context of health monitoring which employs a unified
approach to fault detection, isolation and identification is a single
algorithm. The performance capabilities of our proposed fault diagnosis
methodology is demonstrated and evaluated by its application to a gas turbine
engine through accomplishing state and parameter estimation under simultaneous
and concurrent component fault scenarios. Extensive simulation results are
provided to substantiate and justify the superiority of our proposed fault
diagnosis methodology when compared with another well-known alternative
diagnostic technique that is available in the literature.


title:
Multi-Regge kinematics and the moduli space of Riemann spheres with
  marked points

abstract:
  We show that scattering amplitudes in planar N = 4 Super Yang-Mills in
multi-Regge kinematics can naturally be expressed in terms of single-valued
iterated integrals on the moduli space of Riemann spheres with marked points.
As a consequence, scattering amplitudes in this limit can be expressed as
convolutions that can easily be computed using Stokes' theorem. We apply this
framework to MHV amplitudes to leading-logarithmic accuracy (LLA), and we prove
that at L loops all MHV amplitudes are determined by amplitudes with up to L +
4 external legs. We also investigate non-MHV amplitudes, and we show that they
can be obtained by convoluting the MHV results with a certain helicity flip
kernel. We classify all leading singularities that appear at LLA in the Regge
limit for arbitrary helicity configurations and any number of external legs.
Finally, we use our new framework to obtain explicit analytic results at LLA
for all MHV amplitudes up to five loops and all non-MHV amplitudes with up to
eight external legs and four loops.


title: Adaptive Training of Random Mapping for Data Quantization

abstract:
  Data quantization learns encoding results of data with certain requirements,
and provides a broad perspective of many real-world applications to data
handling. Nevertheless, the results of encoder is usually limited to
multivariate inputs with the random mapping, and side information of binary
codes are hardly to mostly depict the original data patterns as possible. In
the literature, cosine based random quantization has attracted much attentions
due to its intrinsic bounded results. Nevertheless, it usually suffers from the
uncertain outputs, and information of original data fails to be fully preserved
in the reduced codes. In this work, a novel binary embedding method, termed
adaptive training quantization (ATQ), is proposed to learn the ideal transform
of random encoder, where the limitation of cosine random mapping is tackled. As
an adaptive learning idea, the reduced mapping is adaptively calculated with
idea of data group, while the bias of random transform is to be improved to
hold most matching information. Experimental results show that the proposed
method is able to obtain outstanding performance compared with other random
quantization methods.


title:
The resolvent order: a unification of the orders by Zarantonello, by
  Loewner, and by Moreau

abstract:
  We introduce and investigate the resolvent order, which is a binary relation
on the set of firmly nonexpansive mappings. It unifies well-known orders
introduced by Loewner (for positive semidefinite matrices) and by Zarantonello
(for projectors onto convex cones). A connection with Moreau's order of convex
functions is also presented. We also construct partial orders on (quotient sets
of) proximal mappings and convex functions. Various examples illustrate our
results.


title:
Interpretation of measurements of the number of muons in extensive air
  shower experiments

abstract:
  In this paper we analyze the energy evolution of the muon content of air
showers between $10^{18.4}$ and $10^{19.6}$ eV to be able to determine the most
likely mass composition scenario from future number of muons measurements. The
energy and primary mass evolution of the number of muons is studied based on
the Heitler-Matthews model and Monte Carlo simulation of the air shower. A
simple model to describe the evolution of the first and second moments of
number of muons distributions is proposed and validated. An analysis approach
based on the comparison between this model's predictions and data to
discriminate among a set of composition scenarios is presented and tested with
simulations. It is shown that the composition scenarios can be potentially
discriminated under the conditions imposed by the method. The discrimination
power of the proposed analysis is stable under systematic changes of the
absolute number of muons from model predictions and on the scale of the
reconstructed energy.


title: Validity of the CMSSM interpretation of the diphoton excess

abstract:
  It has been proposed that the observed diphoton excess at 750 GeV could be
explained within the constrained minimal supersymmetric standard model via
resonantly produced stop bound states. We reanalyze this scenario critically
and extend previous work to include the constraints from the stability of the
electroweak vacuum and from the decays of the stoponium into a pair of Higgs
bosons. It is shown that the interesting regions of parameter space with a
light stop and Higgs of the desired mass are ruled out by these constraints.
This conclusion is not affected by the presence of the bound states because the
binding energy is usually very small in the regions of parameter space which
can explain the Higgs mass. Thus, this also leads to strong constraints on the
diphoton production cross section which is in general too small.


title:
Chiral Effective Theory Methods and their Application to the Structure
  of Hadrons from Lattice QCD

abstract:
  For many years chiral effective theory (ChEFT) has enabled and supported
lattice QCD calculations of hadron observables by allowing systematic effects
from unphysical lattice parameters to be controlled. In the modern era of
precision lattice simulations approaching the physical point, ChEFT techniques
remain valuable tools. In this review we discuss the modern uses of ChEFT
applied to lattice studies of hadron structure in the context of recent
determinations of important and topical quantities. We consider muon g-2,
strangeness in the nucleon, the proton radius, nucleon polarizabilities, and
sigma terms relevant to the prediction of dark-matter-hadron interaction
cross-sections, among others.


title:
European Union regulations on algorithmic decision-making and a "right
  to explanation"

abstract:
  We summarize the potential impact that the European Union's new General Data
Protection Regulation will have on the routine use of machine learning
algorithms. Slated to take effect as law across the EU in 2018, it will
restrict automated individual decision-making (that is, algorithms that make
decisions based on user-level predictors) which "significantly affect" users.
The law will also effectively create a "right to explanation," whereby a user
can ask for an explanation of an algorithmic decision that was made about them.
We argue that while this law will pose large challenges for industry, it
highlights opportunities for computer scientists to take the lead in designing
algorithms and evaluation frameworks which avoid discrimination and enable
explanation.


title: Dependence of Kinematics on the Age of Stars in the Solar Neighborhood

abstract:
  The variations of kinematic parameters with age are considered for a sample
of 15 402 thin-disk O--F stars with accurate $\alpha$, $\delta$, $\mu$, and
$\pi>3$ mas from the Hipparcos catalogue and radial velocities from the PCRV
catalogue. The ages have been calculated from the positions of the stars on the
Hertzsprung--Russell diagram relative to the isochrones from the Padova
database by taking into account the extinction from the previously constructed
3D analytical model and extinction coefficient $R_V$ from the 3D map of its
variations. Smooth, mutually reconciled variations of the velocity dispersions
$\sigma(U)$, $\sigma(V)$, $\sigma(W)$, solar motion components $U_{\odot}$,
$V_{\odot}$, $W_{\odot}$, Ogorodnikov--Milne model parameters, Oort constants,
and vertex deviation $lxy$ consistent with all of the extraneous results for
which the stellar ages were determined have been found. The velocity dispersion
variations are well fitted by power laws the deviations from which are
explained by the influence of predominantly radial stellar streams: Sirius,
Hyades, $\alpha$~Cet/Wolf~630, and Hercules. The accuracy of determining the
solar motion relative to the local standard of rest is shown to be
fundamentally limited due to these variations of stellar kinematics. The
deviations of our results from those of Dehnen and Binney (1998), the
Geneva--Copenhagen survey of dwarfs, and the Besancon model of the Galaxy are
explained by the use of PCRV radial velocities with corrected systematic
errors.


title:
Undecidable Cases of Model Checking Probabilistic Temporal-Epistemic
  Logic (Extended Abstract)

abstract:
  We investigate the decidability of model-checking logics of time, knowledge
and probability, with respect to two epistemic semantics: the clock and
synchronous perfect recall semantics in partially observed discrete-time Markov
chains. Decidability results are known for certain restricted logics with
respect to these semantics, subject to a variety of restrictions that are
either unexplained or involve a longstanding unsolved mathematical problem. We
show that mild generalizations of the known decidable cases suffice to render
the model checking problem definitively undecidable. In particular, for a
synchronous perfect recall, a generalization from temporal operators with
finite reach to operators with infinite reach renders model checking
undecidable. The case of the clock semantics is closely related to a monadic
second order logic of time and probability that is known to be decidable,
except on a set of measure zero. We show that two distinct extensions of this
logic make model checking undecidable. One of these involves polynomial
combinations of probability terms, the other involves monadic second order
quantification into the scope of probability operators. These results explain
some of the restrictions in previous work.


title:
Two-site Bose-Hubbard model with nonlinear tunneling: classical and
  quantum analysis

abstract:
  The extended Bose-Hubbard model for a double-well potential with atom-pair
tunneling is studied. Starting with a classical analysis we determine the
existence of three different quantum phases: self-trapping, phase-locking and
Josephson states. From this analysis we built the parameter space of quantum
phase transitions between degenerate and non-degenerate ground states driven by
the atom-pair tunneling. Considering only the repulsive case, we confirm the
phase transition by the measure of the energy gap between the ground state and
the first excited state. We study the structure of the solutions of the Bethe
ansatz equations for a small number of particles. An inspection of the roots
for the ground state suggests a relationship to the physical properties of the
system. By studying the energy gap we find that the profile of the roots of the
Bethe ansatz equations is related to a quantum phase transition.


title:
Better Unrelated Machine Scheduling for Weighted Completion Time via
  Random Offsets from Non-Uniform Distributions

abstract:
  In this paper we consider the classic scheduling problem of minimizing total
weighted completion time on unrelated machines when jobs have release times,
i.e, $R | r_{ij} | \sum_j w_j C_j$ using the three-field notation. For this
problem, a 2-approximation is known based on a novel convex programming (J. ACM
2001 by Skutella). It has been a long standing open problem if one can improve
upon this 2-approximation (Open Problem 8 in J. of Sched. 1999 by Schuurman and
Woeginger). We answer this question in the affirmative by giving a
1.8786-approximation. We achieve this via a surprisingly simple linear
programming, but a novel rounding algorithm and analysis. A key ingredient of
our algorithm is the use of random offsets sampled from non-uniform
distributions.
  We also consider the preemptive version of the problem, i.e, $R | r_{ij},pmtn
| \sum_j w_j C_j$. We again use the idea of sampling offsets from non-uniform
distributions to give the first better than 2-approximation for this problem.
This improvement also requires use of a configuration LP with variables for
each job's complete schedules along with more careful analysis. For both
non-preemptive and preemptive versions, we break the approximation barrier of 2
for the first time.


title: A minimum principle for Lagrangian graphs

abstract:
  The classical minimum principle is foundational in convex and complex
analysis and plays an important role in the study of the real and complex
Monge-Ampere equations. This note establishes a minimum principle in Lagrangian
geometry. This principle relates the classical Lagrangian angle of
Harvey-Lawson and the space-time Lagrangian angle introduced recently by
Rubinstein-Solomon. As an application, this gives a new formula for solutions
of the degenerate special Lagrangian equation in space-time in terms of the
(time) partial Legendre transform of a family of solutions of obstacle problems
for the (space) non-degenerate special Lagrangian equation.


title: Multi-View Kernel Consensus For Data Analysis

abstract:
  The input data features set for many data driven tasks is high-dimensional
while the intrinsic dimension of the data is low. Data analysis methods aim to
uncover the underlying low dimensional structure imposed by the low dimensional
hidden parameters by utilizing distance metrics that consider the set of
attributes as a single monolithic set. However, the transformation of the low
dimensional phenomena into the measured high dimensional observations might
distort the distance metric, This distortion can effect the desired estimated
low dimensional geometric structure. In this paper, we suggest to utilize the
redundancy in the attribute domain by partitioning the attributes into multiple
subsets we call views. The proposed methods utilize the agreement also called
consensus between different views to extract valuable geometric information
that unifies multiple views about the intrinsic relationships among several
different observations. This unification enhances the information that a single
view or a simple concatenations of views provides.


title: Rare meson decays with three pairs of quasi-degenerate heavy neutrinos

abstract:
  We consider a scenario of Low Scale Seesaw where the masses of its heavy
Majorana neutrinos are arranged in a pattern of three pairs of quasi degenerate
ones, in the range of O(1-6 GeV). Since they can violate lepton number by two
units, they contribute to rare decays of Ds and Bc mesons, providing, besides,
conditions for maximal CP violation. We found that new phenomenology is
possible depending on how many of on-shell pairs mediate these decays. In
particular, we present new constraints on muon-heavy neutrinos mixing
parameters.


title: Generation and Pruning of Pronunciation Variants to Improve ASR Accuracy

abstract:
  Speech recognition, especially name recognition, is widely used in phone
services such as company directory dialers, stock quote providers or location
finders. It is usually challenging due to pronunciation variations. This paper
proposes an efficient and robust data-driven technique which automatically
learns acceptable word pronunciations and updates the pronunciation dictionary
to build a better lexicon without affecting recognition of other words similar
to the target word. It generalizes well on datasets with various sizes, and
reduces the error rate on a database with 13000+ human names by 42%, compared
to a baseline with regular dictionaries already covering canonical
pronunciations of 97%+ words in names, plus a well-trained
spelling-to-pronunciation (STP) engine.


title: Novel applications of the dispersive optical model

abstract:
  A review of recent developments of the dispersive optical model (DOM) is
presented. Starting from the original work of Mahaux and Sartor, several
necessary steps are developed and illustrated which increase the scope of the
DOM allowing its interpretation as generating an experimentally constrained
functional form of the nucleon self-energy. The method could therefore be
renamed as the dispersive self-energy method.
  The aforementioned steps include the introduction of simultaneous fits of
data for chains of isotopes or isotones allowing a data-driven extrapolation
for the prediction of scattering cross sections and level properties in the
direction of the respective drip lines. In addition, the energy domain for data
was enlarged to include results up to 200 MeV where available. An important
application of this work was implemented by employing these DOM potentials to
the analysis of the (\textit{d,p}) transfer reaction using the adiabatic
distorted wave approximation (ADWA).
  We review the fully non-local DOM potential fitted to ${}^{40}$Ca where
elastic-scattering data, level information, particle number, charge density and
high-momentum-removal $(e,e'p)$ cross sections obtained at Jefferson Lab were
included in the analysis. An important consequence of this new analysis is the
finding that the spectroscopic factor for the removal of valence protons in
this nucleus comes out larger by about 0.15 than the results obtained from the
NIKHEF analysis of their $(e,e'p)$ data. Another important consequence of this
analysis is that it can shed light on the relative importance of two-body and
three-body interactions as far as their contribution to the energy of the
ground state is concerned through application of the energy sum rule.


title: Quantum Hysteresis in Coupled Light-Matter Systems

abstract:
  We investigate the non-equilibrium quantum dynamics of a canonical
light-matter system, namely the Dicke model, when the light-matter interaction
is ramped up and down through a cycle across the quantum phase transition. Our
calculations reveal a rich set of dynamical behaviors determined by the cycle
times, ranging from the slow, near adiabatic regime through to the fast, sudden
quench regime. As the cycle time decreases, we uncover a crossover from an
oscillatory exchange of quantum information between light and matter that
approaches a reversible adiabatic process, to a dispersive regime that
generates large values of light-matter entanglement. The phenomena uncovered in
this work have implications in quantum control, quantum interferometry, as well
as in quantum information theory.


title: Towards Plane Spanners of Degree 3

abstract:
  Let $S$ be a finite set of points in the plane that are in convex position.
We present an algorithm that constructs a plane $\frac{3+4\pi}{3}$-spanner of
$S$ whose vertex degree is at most 3. Let $\Lambda$ be the vertex set of a
finite non-uniform rectangular lattice in the plane. We present an algorithm
that constructs a plane $3\sqrt{2}$-spanner for $\Lambda$ whose vertex degree
is at most 3. For points that are in the plane and in general position, we show
how to compute plane degree-3 spanners with a linear number of Steiner points.


title: Charting the circuit QED design landscape using optimal control theory

abstract:
  With recent improvements in coherence times, superconducting transmon qubits
have become a promising platform for quantum computing. They can be flexibly
engineered over a wide range of parameters, but also require us to identify an
efficient operating regime. Using state-of-the-art quantum optimal control
techniques, we exhaustively explore the landscape for creation and removal of
entanglement over a wide range of design parameters. We identify an optimal
operating region outside of the usually considered strongly dispersive regime,
where multiple sources of entanglement interfere simultaneously, which we name
the quasi-dispersive straddling qutrits (QuaDiSQ) regime. At a chosen point in
this region, a universal gate set is realized by applying microwave fields for
gate durations of 50 ns, with errors approaching the limit of intrinsic
transmon coherence. Our systematic quantum optimal control approach is easily
adapted to explore the parameter landscape of other quantum technology
platforms.


title: Chromospheric and Coronal Wave Generation in a Magnetic Flux Sheath

abstract:
  Using radiation magnetohydrodynamic simulations of the solar atmospheric
layers from the upper convection zone to the lower corona, we investigate the
self-consistent excitation of slow magneto-acoustic body waves (slow modes) in
a magnetic flux concentration. We find that the convective downdrafts in the
close surroundings of a two-dimensional flux slab "pump" the plasma inside it
in the downward direction. This action produces a downflow inside the flux
slab, which encompasses ever higher layers, causing an upwardly propagating
rarefaction wave. The slow mode, excited by the adiabatic compression of the
downflow near the optical surface, travels along the magnetic field in the
upward direction at the tube speed. It develops into a shock wave at
chromospheric heights, where it dissipates, lifts the transition region, and
produces an offspring in the form of a compressive wave that propagates further
into the corona. In the wake of downflows and propagating shock waves, the
atmosphere inside the flux slab in the chromosphere and higher tends to
oscillate with a period of $\nu\approx 4$~mHz. We conclude that this process of
"magnetic pumping" is a most plausible mechanism for the direct generation of
longitudinal chromospheric and coronal compressive waves within magnetic flux
concentrations, and it may provide an important heat source in the
chromosphere. It may also be responsible for certain types of dynamic fibrils.


title: The Erd\"os-Hajnal Conjecture---A Survey

abstract:
  The Erd\"os-Hajnal conjecture states that for every graph $H$, there exists a
constant $\delta(H) > 0$ such that every graph $G$ with no induced subgraph
isomorphic to $H$ has either a clique or a stable set of size at least
$|V(G)|^{\delta(H)}$. This paper is a survey of some of the known results on
this conjecture.