title: Classifying matchbox manifolds

abstract:
  Matchbox manifolds are foliated spaces with totally disconnected
transversals. Two matchbox manifolds which are homeomorphic have return
equivalent dynamics, so that invariants of return equivalence can be applied to
distinguish non-homeomorphic matchbox manifolds. In this work we study the
problem of showing the converse implication: when does return equivalence imply
homeomorphism? For the class of weak solenoidal matchbox manifolds, we show
that if the base manifolds satisfy a strong form of the Borel Conjecture, then
return equivalence for the dynamics of their foliations implies the total
spaces are homeomorphic. In particular, we show that two equicontinuous
$\mT^n$--like matchbox manifolds of the same dimension are homeomorphic if and
only if their corresponding restricted pseudogroups are return equivalent. At
the same time, we show that these results cannot be extended to include the
"\emph{adic}-surfaces", which are a class of weak solenoids fibering over a
closed surface of genus 2.


title: Tachyonic fields in cosmology

abstract:
  The possibility of explanation of accelerated expansion of the Universe by
tachyonic scalar fields which homogeneously fill the world is discussed. The
dependences of potential and kinetic term on scale factor are deduced for the
case of quintessential and phantom dark energy with generalized linear
barotropic equation of state. The possibility to distinguish the tachyonic
scalar field as dark energy from other scalar field models, especially from
classical scalar field, is analyzed.


title:
Improving Software Developer's Competence: Is the Personal Software
  Process Working?

abstract:
  Emerging agile software development methods are people oriented development
approaches to be used by the software industry. The personal software process
(PSP) is an accepted method for improving the capabilities of a single software
engineer. Five original hypotheses regarding the impact of the PSP to
individual performance are tested. Data is obtained from 58 computer science
students in three university courses on the master level, which were held in
two different educational institutions in Finland and Denmark. Statistical data
treatment shows that the use of PSP did not improve size and time estimation
skills but that the productivity did not decrease and the resulting product
quality was improved. The implications of these findings are briefly addressed.


title: Domain wall displacement by remote spin-current injection

abstract:
  We demonstrate numerically the ability to displace a magnetic domain wall by
a remote spin current injection. We consider a long and narrow magnetic
nanostripe with a single domain wall (DW). The spin-polarized current is
injected perpendicularly to the plane of the film (CPP) through a small
nanocontact which is located at certain distance from the domain wall initial
position. We show theoretically that the DW motion can be initiated not only by
conventional spin-transfer torque but also by indirect spin-torque, created by
a remote spin-current injection and then transferred to the DW by the
exchange-spring mechanism. An analytical description of this effect is
proposed. This finding may lead to a solution of bottleneck problems of DW
motion-based spintronic and neuromorphic devices with perpendicular
spin-current injection.


title: Traffic disruption and recovery in road networks

abstract:
  We study the impact of disruptions on road networks, and the recovery process
after the disruption is removed from the system. Such disruptions could be
caused by vehicle breakdown or illegal parking. We analyze the transient
behavior using domain wall theory, and compare these predictions with
simulations of a stochastic cellular automaton model. We find that the domain
wall model can reproduce the time evolution of flow and density during the
disruption and the recovery processes, for both one-dimensional systems and
two-dimensional networks.


title: Laser-induced atomic adsorption: a mechanism for nanofilm formation

abstract:
  We demonstrate and interpret a technique of laser-induced formation of thin
metallic films using alkali atoms on the window of a dense-vapour cell. We show
that this intriguing photo-stimulated process originates from the adsorption of
Cs atoms via the neutralisation of Cs$^+$ ions by substrate electrons. The
Cs$^+$ ions are produced via two-photon absorption by excited Cs atoms very
close to the surface, which enables the transfer of the laser spatial intensity
profile to the film thickness. An initial decrease of the surface work function
is required to guarantee Cs$^+$ neutralisation and results in a threshold in
the vapour density. This understanding of the film growth mechanism may
facilitate the development of new techniques of laser-controlled lithography,
starting from thermal vapours.


title: Lie Subalgebras of vector fields and the Jacobian Conjecture

abstract:
  We study Lie subalgebras $L$ of the vector fields $\mathrm{Vec}^{c}({\mathbb
A}^{2})$ of affine 2-space ${\mathbb A}^{2}$ of constant divergence, and we
classify those $L$ which are isomorphic to the Lie algebra $\mathfrak{aff}_{2}$
of the group $\mathrm{Aff}_{2}(K)$ of affine transformations of ${\mathbb
A}^{2}$. We then show that the following three statements are equivalent: (i)
The Jacobian Conjecture holds in dimension 2; (ii) All Lie subalgebras $L
\subset \mathrm{Vec}^{c}({\mathbb A}^{2})$ isomorphic to $\mathfrak{aff}_{2}$
are conjugate under $\mathrm{Aut}({\mathbb A}^{2})$; (iii) All Lie subalgebras
$L \subset \mathrm{Vec}^{c}({\mathbb A}^{2})$ isomorphic to
$\mathfrak{aff}_{2}$ are algebraic.


title:
Thermodynamic Self Assembly of Two-Dimensional pi-Conjugated
  Metal-Porphyrin Covalent Organic Frameworks by On-Site Equilibrium
  Polymerization

abstract:
  Two dimensional pi conjugated metal porphyrin covalent organic frameworks
were produced in aqueous solution on an iodine-modified Au(111) surface by on
site azomethine coupling of Fe(III) 5,10,15,20 tetrakis(4 aminophenyl)porphyrin
(FeTAPP) with terephthal dicarboxaldehyde and investigated in detail using
in-situ scanning tunneling microscopy. Mixed covalent organic porphyrin
frameworks consisting of FeTAPP and metal-free TAPP (H2TAPP) were prepared
through simultaneous adsorption in a mixed solution as well as partial
replacement of FeTAPP by H2TAPP in an as prepared metal porphyrin framework. In
the mixed framework, the relative distribution of FeTAPP to H2TAPP was not
random and revealed a preference for homo-connection rather than
heteroconnection. The construction of substrate-supported, pi conjugated
covalent frameworks from multiple building blocks, including metal centers,
will be of significant utility in the design of functional molecular
nanoarchitectures.


title: Type III and N universal spacetimes

abstract:
  Universal spacetimes are spacetimes for which all conserved symmetric rank-2
tensors, constructed as contractions of polynomials from the metric, the
Riemann tensor and its covariant derivatives of arbitrary order, are multiples
of the metric. Consequently, metrics of universal spacetimes solve vacuum
equations of all gravitational theories with Lagrangian being a polynomial
curvature invariant constructed from the metric, the Riemann tensor and its
derivatives of arbitrary order. In the literature, universal metrics are also
discussed as metrics with vanishing quantum corrections and as classical
solutions to string theory. Widely known examples of universal metrics are
certain Ricci-flat pp waves.
  In this paper, we start a general study of geometric properties of universal
metrics in arbitrary dimension and we arrive at a broader class of such
metrics. In contrast with pp waves, these universal metrics also admit
non-vanishing cosmological constant and in general do not have to possess a
covariantly constant or recurrent null vector field. First, we show that a
universal spacetime is necessarily a CSI spacetime, i.e. all curvature
invariants constructed from the Riemann tensor and its derivatives are
constant. Then we focus on type N spacetimes, where we arrive at a simple
necessary and sufficient condition: a type N spacetime is universal if and only
if it is an Einstein Kundt spacetime. A class of type III Kundt universal
metrics is also found. Several explicit examples of universal metrics are
presented.


title: Will Comet 209P/LINEAR Generate the Next Meteor Storm?

abstract:
  Previous studies have suggested that Comet 209P/LINEAR may produce strong me-
teor activity on Earth on 2014 May 24; however, exact timing and activity level
is difficult to estimate due to the limited physical observations of the comet.
Here we reanalyze the optical observations of 209P/LINEAR obtained during its
2009 appari- tion. We find that the comet is relatively depleted in dust
production, with Af {\rho} at 1 cm level within eight months around its
perihelion. This feature suggested that this comet may be currently
transitioning from typical comet to a dormant comet. Syn- dyne simulation shows
that the optical cometary tail is dominated by larger particles with {\beta} ~
0.003. Numerical simulations of the cometary dust trails confirm the arrival of
particles on 2014 May 24 from some of the 1798-1979 trails. The nominal radiant
is at RA 122 +/- 1 deg, Dec 79 +/- 1 deg (J2000) in the constellation of
Camelopardalis. Given that the comet is found to be depleted in dust
production, we concluded that a meteor storm (ZHR>=1000) may be unlikely.
However, our simulation also shows that the size distribution of the arrived
particles is skewed strongly to larger particles. Coupling with the result of
syndyne simulation, we think that the event, if detectable, may be dominated by
bright meteors. We encourage observers to monitor the expected meteor event as
it will provide us with rare direct information on the dynamical history of
209P/LINEAR which is otherwise irretrievably lost.


title: Variance matters (in stochastic dividend discount models)

abstract:
  Stochastic dividend discount models (Hurley and Johnson, 1994 and 1998, Yao,
1997) present expressions for the expected value of stock prices when future
dividends evolve according to some random scheme. In this paper we try to offer
a more precise view on this issue proposing a closed-form formula for the
variance of stock prices.


title:
Critical Missing Equation of Quantum Physics for Understanding Atomic
  Structures

abstract:
  This paper presents an optimization approach to explain why and how a quantum
system evolves from an arbitrary initial state to a stationary state,
satisfying the time-independent Schr\"{o}dinger equation. It also points out
the inaccuracy of this equation, which is critial important in quantum
mechanics and quantum chemistry, due to a fundamental flaw in it conflicting
with the physical reality. The some directions are suggested on how to modify
the equation to fix the problem


title:
Strain-Tunable Magnetocrystalline Anisotropy in Epitaxial Y3Fe5O12 Thin
  Films

abstract:
  We demonstrate strain-tuning of magnetocrystalline anisotropy over a range of
more than one thousand Gauss in epitaxial Y3Fe5O12 films of excellent
crystalline quality grown on lattice-mismatched Y3Al5O12 substrates.
Ferromagnetic resonance (FMR) measurements reveal a linear dependence of both
out-of-plane and in-plane uniaxial anisotropy on the strain-induced tetragonal
distortion of Y3Fe5O12. Importantly, we find the spin mixing conductance G_r
determined from inverse spin Hall effect and FMR linewidth broadening remains
large: G_r = 3.33 x 10^14 Ohm^-1m^-2 in Pt/Y3Fe5O12/Y3Al5O12 heterostructures,
quite comparable to the value found in Pt/Y3Fe5O12 grown on lattice-matched
Gd3Ga5O12 substrates.


title: Mass of a Black Hole Firewall

abstract:
  Quantum entanglement of Hawking radiation has been supposed to give rise to a
Planck density "firewall" near the event horizon of old black holes. We show
that Planck density firewalls are excluded by Einstein's equations for black
holes of mass exceeding the Planck mass. We find an upper limit of $1/(8\pi M)$
to the surface density of a firewall in a Schwarzschild black hole of mass $M$,
translating for astrophysical black holes into a firewall density smaller than
Planck density by more than 30 orders of magnitude. A strict upper limit on the
firewall density is given by the Planck density times the ratio $M_{\rm
Pl}/(8\pi M)$.


title: Magnetism in nanoparticle LaCoO3

abstract:
  LaCoO3 (LCO) nanoparticles were synthesized and their magnetic and structural
properties were examined using SQUID magnetometery and neutron diffraction. The
nanoparticles exhibit ferromagnetic long-range order beginning at T_C
approximately 87K that persists to low temperatures. This behavior is
contrasted with the ferromagnetism of bulk LCO, which also starts at T_C
approximately 87K but is suppressed below a second transition at T_o
approximately 37K, due to a structural phase transition. The ferromagnetism in
both systems is attributed to the tensile stress from particle surfaces and
impurity phase interfaces. This stress locally increases the Co-O-Co bond angle
gamma, and competes with the thermal contraction of the lattice. It has
recently been shown that LCO loses long-range ferromagnetic order when gamma
decreases below the critical value gamma_c = 162.8 degrees. Consistent with
this model, we show that gamma in nanoparticles remains larger than gamma_c at
low temperatures, likely a consequence of all spins being in close proximity to
surfaces or interfaces.


title: 5 (Upgradable to 25 keV) Free Electron Laser (FEL) Facility

abstract:
  A Free Electron Laser (FEL) facility utilizing a recirculated Superconducting
Radio Frequency (SRF) linear accelerator (linac) provides the opportunity to
achieve about five times greater photon energy than an unrecirculated linac of
similar cost. > A 4 GeV SRF, cw, electron linac can be used to drive an FEL
producing 5 keV photons. The SLAC National Accelerator Laboratory, a Department
of Energy (DOE) Basic Energy Sciences (BES) laboratory, proposes to utilize a 4
GeV unrecirculated, SRF, linac in a segment of existing linac tunnel. > For an
initial investment similar to that of the proposed SLAC strategy, a
recirculated SRF linac system could deliver the 4 GeV electrons for photon
energies of 5 keV and provide an upgrade path to photon energies of 25 keV. >
Further support amounting to about a third of the initial investment would
provide upgrade funds for additional SRF linac and cryogenic capacity
sufficient to provide electron energies appropriate for 25 keV photons matching
the European XFEL.


title: Cubic-interaction-induced deformations of higher-spin symmetries

abstract:
  The deformations of higher-spin symmetries induced by cubic interactions of
symmetric massless bosonic fields are analyzed within the metric-like
formalism. Our analysis amends the existing classification according to
gauge-algebra deformations taking into account also gauge-transformation
deformations. In particular, we identify a class of couplings which leave the
gauge algebra Abelian but deform one (out of three) gauge transformation, and
another class of couplings which deform all three gauge transformations in
(A)dS but only two in the flat-space limit. The former class is related to
higher-spin algebra multiplets (representations of the global algebra) together
with the massless-massive-massive couplings, which we also briefly discuss. The
latter class is what makes (A)dS a distinguished background for higher-spin
interactions and includes in particular the gravitational interactions of
higher-spin fields, retrospectively accounting for the Fradkin-Vasiliev
solution to the Aragon-Deser problem. We also study the restriction of gauge
symmetries to global symmetries (higher-spin algebra) discussing the invariant
bilinear form and the cyclicity of the structure constants. A possible
generalization of the analysis to partially-massless fields is also commented.


title: Majority is not Enough: Bitcoin Mining is Vulnerable

abstract:
  The Bitcoin cryptocurrency records its transactions in a public log called
the blockchain. Its security rests critically on the distributed protocol that
maintains the blockchain, run by participants called miners. Conventional
wisdom asserts that the protocol is incentive-compatible and secure against
colluding minority groups, i.e., it incentivizes miners to follow the protocol
as prescribed.
  We show that the Bitcoin protocol is not incentive-compatible. We present an
attack with which colluding miners obtain a revenue larger than their fair
share. This attack can have significant consequences for Bitcoin: Rational
miners will prefer to join the selfish miners, and the colluding group will
increase in size until it becomes a majority. At this point, the Bitcoin system
ceases to be a decentralized currency.
  Selfish mining is feasible for any group size of colluding miners. We propose
a practical modification to the Bitcoin protocol that protects against selfish
mining pools that command less than 1/4 of the resources. This threshold is
lower than the wrongly assumed 1/2 bound, but better than the current reality
where a group of any size can compromise the system.


title:
A Message Passing Strategy for Decentralized Connectivity Maintenance in
  Agent Removal

abstract:
  In a multi-agent system, agents coordinate to achieve global tasks through
local communications. Coordination usually requires sufficient information
flow, which is usually depicted by the connectivity of the communication
network. In a networked system, removal of some agents may cause a
disconnection. In order to maintain connectivity in agent removal, one can
design a robust network topology that tolerates a finite number of agent
losses, and/or develop a control strategy that recovers connectivity. This
paper proposes a decentralized control scheme based on a sequence of
replacements, each of which occurs between an agent and one of its immediate
neighbors. The replacements always end with an agent, whose relocation does not
cause a disconnection. We show that such an agent can be reached by a local
rule utilizing only some local information available in agents' immediate
neighborhoods. As such, the proposed message passing strategy guarantees the
connectivity maintenance in arbitrary agent removal. Furthermore, we
significantly improve the optimality of the proposed scheme by incorporating
$\delta$-criticality (i.e. the criticality of an agent in its
$\delta$-neighborhood).


title:
Pseudodifferential operators of mixed type adapted to distributions of
  $k$-planes

abstract:
  We study the phenomena that arise when we combine the standard
pseudodifferential operators with those operators that appear in the study of
some sub-elliptic estimates, and on strongly pseudoconvex domains. The algebra
of operators we introduce is geometrically invariant, and is adapted to a
smooth distribution of tangent subspaces of constant rank. We isolate certain
ideals in the algebra whose analysis is of particular interest.


title:
Electron laser acceleration in vacuum by a quadratically chirped laser
  pulse

abstract:
  Single MeV electrons subjected in vacuum to single high-intensity
quadratically-chirped laser pulses are shown to gain multi-GeV energies. The
laser pulses are modeled by finite-duration trapezoidal and $\cos^2$
pulse-shapes and the equations of motion are solved numerically. It is found
that, typically, the maximum energy gain from interaction with a quadratic
chirp is about half of what would be gained from a linear chirp.


title:
Fermi liquid breakdown and evidence for superconductivity in
  YFe$_2$Ge$_2$

abstract:
  In the d-electron system YFe$_2$Ge$_2$, an unusually high and temperature
dependent Sommerfeld ratio of the specific heat capacity $C/T \sim
100~\mathrm{mJ/(molK^2)}$ and an anomalous power law temperature dependence of
the electrical resistivity $\rho \simeq \rho_0 + AT^{3/2}$ signal Fermi liquid
breakdown, probably connected to a close-by quantum critical point. Full
resistive transitions, accompanied by DC diamagnetic screening fractions of up
to 80\% suggest that pure samples of YFe$_2$Ge$_2$ superconduct below
$1.8~\mathrm{K}$.


title:
Detection of Potential Transit Signals in Sixteen Quarters of Kepler
  Mission Data

abstract:
  We present the results of a search for potential transit signals in four
years of photometry data acquired by the Kepler Mission. The targets of the
search include 111,800 stars which were observed for the entire interval and
85,522 stars which were observed for a subset of the interval. We found that
9,743 targets contained at least one signal consistent with the signature of a
transiting or eclipsing object, where the criteria for detection are
periodicity of the detected transits, adequate signal-to-noise ratio, and
acceptance by a number of tests which reject false positive detections. When
targets that had produced a signal were searched repeatedly, an additional
6,542 signals were detected on 3,223 target stars, for a total of 16,285
potential detections. Comparison of the set of detected signals with a set of
known and vetted transit events in the Kepler field of view shows that the
recovery rate for these signals is 96.9%. The ensemble properties of the
detected signals are reviewed.


title: A Solution to the Lorentzian Quantum Reality Problem

abstract:
  The quantum reality problem is that of finding a mathematically precise
definition of a sample space of configurations of beables, events, histories,
paths, or other mathematical objects, and a corresponding probability
distribution, for any given closed quantum system. Given a solution, we can
postulate that physical reality is described by one randomly chosen
configuration drawn from the sample space. For a physically sensible solution,
this postulate should imply quasiclassical physics in realistic models. In
particular, it should imply the validity of Copenhagen quantum theory and
classical dynamics in their respective domains. A Lorentzian solution applies
to relativistic quantum theory or quantum field theory in Minkowski space and
is defined in a way that respects Lorentz symmetry. We outline a new solution
to the non-relativistic and Lorentzian quantum reality problems, and associated
new generalizations of quantum theory.


title: Design of a millimetre-scale magnetic surface trap for cold atoms

abstract:
  We study a novel millimetre-scale magnetic trap for ultracold atoms, in which
the current carrying conductors can be situated outside the vacuum region, a
few mm away from the atoms. This design generates a magnetic field gradient in
excess of \SI{1000}{G/cm} at a distance of \SI{2}{mm} from the conductors. We
perform electromagnetic and thermo-mechanical characterisation using Finite
Element Methods (FEM). The predicted behaviour has been verified by electrical
and thermal measurements on a prototype, but has not been implemented on an
apparatus with cold atoms. Operating this trap at the highest gradient allows
for rapid evaporative cooling comparable to that achieved by atom chips.


title: Capturing Variation and Uncertainty in Human Judgment

abstract:
  The well-studied problem of statistical rank aggregation has been applied to
comparing sports teams, information retrieval, and most recently to data
generated by human judgment. Such human-generated rankings may be substantially
different from traditional statistical ranking data. In this work, we show that
a recently proposed generalized random utility model reveals distinctive
patterns in human judgment across three different domains, and provides a
succinct representation of variance in both population preferences and
imperfect perception. In contrast, we also show that classical statistical
ranking models fail to capture important features from human-generated input.
Our work motivates the use of more flexible ranking models for representing and
describing the collective preferences or decision-making of human participants.


title: Quantization of the Atom plus Attempting to Answer Heilbron & Kuhn

abstract:
  The idea of atoms is old but X-rays provided the first probe into the
physical atom. Photographs of X-ray scattering from crystals -Laue spots- were
the first visual proof for the physical existence of atoms arranged in a
perfect geometric pattern. Thereby conclusively established the stability and
physical reality of atoms. The Braggs developed Laue technique to study atoms.
Moseley applied (Bragg) X-ray spectroscopy to determine the nuclear charge
number of Rutherford atom. We argue that Bohr also at Manchester and
contemporary of Moseley likely was inspired by Laue discovery to get busy with
the mechanics of the nuclear atom. Roentgens discovery was awarded the first
Nobel prize ever in 1901, Laue was honored in 1914, the Braggs in 1915, making
Lawrence Bragg then at 25 the youngest ever. Eleven of the cited authors (Bohr
himself included) in the trilogy (but not Nicholson the most cited), were later
recognized by ten Noble prize awards, seven Laureates in physics and four in
chemistry. The ensuing synergy between science and Nobel honors has been
critical.


title:
Radiation trapping and L\'{e}vy flights in atomic vapours: an
  introductory review

abstract:
  Multiple scattering is a process in which a particle is repeatedly deflected
by other particles. In an overwhelming majority of cases, the ensuing random
walk can successfully be described through Gaussian, or normal, statistics.
However, like a (growing) number of other apparently inofensive systems,
diffusion of light in dilute atomic vapours eludes this familiar
interpretation, exhibiting a superdiffusive behavior. As opposed to normal
diffusion, whereby the particle executes steps in random directions but with
lengths slightly varying around an average value (like a drunkard whose next
move is unpredictable but certain to within a few tens of centimeters),
superdiffusion is characterized by sudden abnormally long steps (L\'{e}vy
flights) interrupting sequences of apparently regular jumps which, although
very rare, determine the whole dynamics of the system. The formal statistics
tools to describe superdiffusion already exist and rely on stable, well
understood distributions. As scientists become aware of, and more familiar
with, this non-orthodox possibility of interpretation of random phenomena, new
systems are discovered or re-interpreted as following L\'{e}vy statistics.
Propagation of light in resonant atomic vapours is one of these systems that
have been studied for decades and have only recently been shown to be the scene
of L\'{e}vy flights.


title:
Charge density and conductivity of disordered Berry-Mondragon graphene
  nanoribbons

abstract:
  We consider gated graphene nanoribbons subject to Berry-Mondragon boundary
conditions in the presence of weak impurities. Using field--theoretical
methods, we calculate the density of charge carriers (and, thus, the quantum
capacitance) as well as the optical and DC conductivities at zero temperature.
We discuss in detail their dependence on the gate (chemical) potential, and
reveal a non-linear behaviour induced by the quantization of the transversal
momentum.


title: Quark mass functions and pion structure in Minkowski space

abstract:
  We present a study of the dressed quark mass function and the pion structure
in Minkowski space using the Covariant Spectator Theory. The quark propagators
are dressed with the same kernel that describes the interaction between
different quarks. We use an interaction kernel in momentum space that is a
relativistic generalization of the linear confining q-qbar potential and a
constant potential shift that defines the energy scale. The confining
interaction has a Lorentz scalar part that is not chirally invariant by itself
but decouples from the equations in the chiral limit and therefore allows the
Nambu-Jona-Lasinio mechanism to work. We adjust the parameters of our quark
mass function calculated in Minkowski-space to agree with Lattice QCD data
obtained in Euclidean space. Results of a calculation of the pion
electromagnetic form factor in the relativistic impulse approximation using the
same mass function are presented and compared with experimental data.


title:
Derivation of the anisotropy profile, constraints on the local velocity
  dispersion, and implications for direct detection

abstract:
  We study the implications of a pseudo-phase-space density power-law for the
anisotropy profile of a Milky Way-like dark matter halo. Requiring that the
anisotropy parameter does not take non-physical values within the virial radius
places a maximum value on the local radial velocity dispersion. For a plausible
range of halo parameters, it is possible to take a local total velocity
dispersion of up to about $300\,\mathrm{km/s}$. Making this choice uniquely
specifies the anisotropy and dispersion profiles. We introduce a way to model
the local velocity distribution that incorporates this anisotropy and study the
impact on direct detection.


title:
Application of Cybernetics and Control Theory for a New Paradigm in
  Cybersecurity

abstract:
  A significant limitation of current cyber security research and techniques is
its reactive and applied nature. This leads to a continuous 'cyber cycle' of
attackers scanning networks, developing exploits and attacking systems, with
defenders detecting attacks, analyzing exploits and patching systems. This
reactive nature leaves sensitive systems highly vulnerable to attack due to
un-patched systems and undetected exploits. Some current research attempts to
address this major limitation by introducing systems that implement moving
target defense. However, these ideas are typically based on the intuition that
a moving target defense will make it much harder for attackers to find and scan
vulnerable systems, and not on theoretical mathematical foundations. The
continuing lack of fundamental science and principles for developing more
secure systems has drawn increased interest into establishing a 'science of
cyber security'. This paper introduces the concept of using cybernetics, an
interdisciplinary approach of control theory, systems theory, information
theory and game theory applied to regulatory systems, as a foundational
approach for developing cyber security principles. It explores potential
applications of cybernetics to cyber security from a defensive perspective,
while suggesting the potential use for offensive applications. Additionally,
this paper introduces the fundamental principles for building non-stationary
systems, which is a more general solution than moving target defenses. Lastly,
the paper discusses related works concerning the limitations of moving target
defense and one implementation based on non-stationary principles.


title: Convexity in source separation: Models, geometry, and algorithms

abstract:
  Source separation or demixing is the process of extracting multiple
components entangled within a signal. Contemporary signal processing presents a
host of difficult source separation problems, from interference cancellation to
background subtraction, blind deconvolution, and even dictionary learning.
Despite the recent progress in each of these applications, advances in
high-throughput sensor technology place demixing algorithms under pressure to
accommodate extremely high-dimensional signals, separate an ever larger number
of sources, and cope with more sophisticated signal and mixing models. These
difficulties are exacerbated by the need for real-time action in automated
decision-making systems.
  Recent advances in convex optimization provide a simple framework for
efficiently solving numerous difficult demixing problems. This article provides
an overview of the emerging field, explains the theory that governs the
underlying procedures, and surveys algorithms that solve them efficiently. We
aim to equip practitioners with a toolkit for constructing their own demixing
algorithms that work, as well as concrete intuition for why they work.


title: Error-disturbance relations for finite dimensional systems

abstract:
  We propose an error-disturbance relation for general observables on finite
dimensional Hilbert spaces based on operational notions of error and
disturbance. For two-dimensional systems we derive tight inequalities
expressing the trade-off between accuracy and disturbance.


title: A geometric approach to discrete connections on principal bundles

abstract:
  This work revisits, from a geometric perspective, the notion of discrete
connection on a principal bundle, introduced by M. Leok, J. Marsden and A.
Weinstein. It provides precise definitions of discrete connection, discrete
connection form and discrete horizontal lift and studies some of their basic
properties and relationships. An existence result for discrete connections on
principal bundles equipped with appropriate Riemannian metrics is proved.


title: Arbitrary Bending Plasmonic Light Waves

abstract:
  We demonstrate the generation of self-accelerating surface plasmon beams
along arbitrary caustic curvatures. These plasmonic beams are excited by
free-space beams through a two-dimensional binary plasmonic phase mask, which
provides the missing momentum between the two beams in the direction of
propagation, and sets the required phase for the plasmonic beam in the
transverse direction. We examine the cases of paraxial and non-paraxial
curvatures and show that this highly versatile scheme can be designed to
produce arbitrary plasmonic self-accelerating beams. Several different
plasmonic beams, which accelerate along polynomial and exponential
trajectories, are demonstrated both numerically and experimentally, with a
direct measurement of the plasmonic light intensity using a
near-field-scanning-optical-microscope.


title: Tracking Deformable Parts via Dynamic Conditional Random Fields

abstract:
  Despite the success of many advanced tracking methods in this area, tracking
targets with drastic variation of appearance such as deformation, view change
and partial occlusion in video sequences is still a challenge in practical
applications. In this letter, we take these serious tracking problems into
account simultaneously, proposing a dynamic graph based model to track object
and its deformable parts at multiple resolutions. The method introduces well
learned structural object detection models into object tracking applications as
prior knowledge to deal with deformation and view change. Meanwhile, it
explicitly formulates partial occlusion by integrating spatial potentials and
temporal potentials with an unparameterized occlusion handling mechanism in the
dynamic conditional random field framework. Empirical results demonstrate that
the method outperforms state-of-the-art trackers on different challenging video
sequences.


title: On the rationality of the moduli of higher spin curves in low genus

abstract:
  The global geometry of the moduli spaces of higher spin curves and their
birational classification is largely unknown for g >= 2 and r > 2. Using quite
related geometric constructions, we almost complete the picture of the known
results in genus g <= 4 showing the rationality of the moduli spaces of even
and odd 4-spin curves of genus 3, of odd spin curves of genus 4 and of 3-spin
curves of genus 4.


title:
Radiatively and thermally driven self-consistent bipolar outflows from
  accretion discs around compact objects

abstract:
  We investigate the role of radiative driving of shock ejected bipolar
outflows from advective accretion discs in a self consistent manner. Radiations
from the inner disc affects the subsonic part of the jet while those from the
pre-shock disc affects the supersonic part, and there by constitutes a multi
stage acceleration process. We show that the radiation from the inner disc not
only accelerate but also increase the mass outflow rate, while the radiation
from the pre-shock disc only increases the kinetic energy of the flow. With
proper proportions of these two radiations, very high terminal speed is
possible. We also estimated the post-shock luminosity from the pre-shock
radiations, and showed that with the increase of viscosity parameter the disc
becomes more luminous, and the resulting jet simultaneously becomes faster.
This mimics the production of steady mildly relativistic but stronger jets as
micro-quasars moves from low hard to intermediate hard spectral states.


title: Recent results in Ring Diagram analysis

abstract:
  The ring-diagram technique was developed by Frank Hill 25 years ago and
developed quickly during the late 1990s. It is nowadays one of the most
commonly used techniques in local helioseismology. The method consists in the
power spectral analysis of solar acoustic oscillations on small regions (2 to
30 degrees) of the solar surface. The power spectrum resembles a set of
trumpets nested inside each other and, for a given frequency, it looks like a
ring, hence the technique's name. It provides information on the horizontal
flow field and thermodynamic structure in the layers immediately below the
photosphere. With data regularly provided by MDI (on board SOHO), GONG+ network
and more recently HMI (on SDO), many important results have been achieved. In
recently years, these results include estimations of the meridional circulation
and its evolution with solar cycle; flows associated with active regions, as
well as, flow divergence and vorticity; and thermal structure beneath and
around active regions. Much progress is expected with data now provided by
HMI's high spatial resolution observations and high duty cycle. There are two
data processing pipelines (GONG and HMI) providing free access to the data and
the results of the ring-diagram analysis. Here we will discuss the most recent
results and improvements in the technique, as well as, the many challenges that
still remain.


title:
The five dimensional universal hypermultiplet and the cosmological
  constant problem

abstract:
  We model the universe as a 3-brane embedded in five dimensional spacetime
with N=2 supersymmetry. The presence of the scalar fields of the universal
hypermultiplet in the bulk results in a positive pressure effectively reducing
the value of the cosmological constant and thereby providing a possible answer
as to why the measured value of the cosmological constant is many orders of
magnitude smaller than predicted from the vacuum energy. The solution allows
for any number of parallel branes to exist and relates their cosmological
constants (as well as matter densities and radiation pressures) to the value of
the dilaton in the extra dimension. The results we find can be thought of as
first order approximations, satisfying supersymmetry breaking and the
Bogomol'nyi-Prasad-Sommerfield (BPS) conditions in the bulk only.


title: Sectional curvature for Riemannian manifolds with density

abstract:
  In this paper we introduce two new notions of sectional curvature for
Riemannian manifolds with density. Under both notions of curvature we classify
the constant curvature manifolds. We also prove generalizations of the theorems
of Cartan-Hadamard, Synge, and Bonnet-Myers as well as a generalization of the
(non-smooth) 1/4-pinched sphere theorem. The main idea is to modify the radial
curvature equation and second variation formula and then apply the techniques
of classical Riemannian geometry to these new equations.


title:
Cauchy horizon stability in a collapsing spherical dust cloud I:
  geometric optic approximation and spherically symmetric test fields

abstract:
  A spherical dust cloud which is initially at rest and which has a
monotonously decaying density profile collapses and forms a shell-focussing
singularity. Provided the density profile is not too flat, meaning that its
second radial derivative is negative at the center, this singularity is visible
to local, and sometimes even to global observers. According to the strong
cosmic censorship conjecture, such naked singularities should be unstable under
generic, nonspherical perturbations of the initial data or when more realistic
matter models are considered.
  In an attempt to gain some understanding about this stability issue, in this
work we initiate the analysis of a simpler but related problem. We discuss the
stability of test fields propagating in the vicinity of the Cauchy horizon
associated to the naked central singularity. We first study the high-frequency
limit and show that the fields undergo a blueshift as they approach the Cauchy
horizon. However, in contrast to what occurs at inner horizons of black holes,
we show that the blueshift is uniformly bounded along incoming and outgoing
null rays. Motivated by this boundedness result, we take a step beyond the
geometric optic approximation and consider the Cauchy evolution of spherically
symmetric test scalar fields. We prove that under reasonable conditions on the
initial data a suitable rescaled field can be continuously extended to the
Cauchy horizon. In particular, this result implies that the physical field is
everywhere finite on the Cauchy horizon away from the central singularity.


title: Initial explorations of ARM processors for scientific computing

abstract:
  Power efficiency is becoming an ever more important metric for both high
performance and high throughput computing. Over the course of next decade it is
expected that flops/watt will be a major driver for the evolution of computer
architecture. Servers with large numbers of ARM processors, already ubiquitous
in mobile computing, are a promising alternative to traditional x86-64
computing. We present the results of our initial investigations into the use of
ARM processors for scientific computing applications. In particular we report
the results from our work with a current generation ARMv7 development board to
explore ARM-specific issues regarding the software development environment,
operating system, performance benchmarks and issues for porting High Energy
Physics software.


title: There is a VaR beyond usual approximations

abstract:
  Basel II and Solvency 2 both use the Value-at-Risk (VaR) as the risk measure
to compute the Capital Requirements. In practice, to calibrate the VaR, a
normal approximation is often chosen for the unknown distribution of the yearly
log returns of financial assets. This is usually justified by the use of the
Central Limit Theorem (CLT), when assuming aggregation of independent and
identically distributed (iid) observations in the portfolio model. Such a
choice of modeling, in particular using light tail distributions, has proven
during the crisis of 2008/2009 to be an inadequate approximation when dealing
with the presence of extreme returns; as a consequence, it leads to a gross
underestimation of the risks. The main objective of our study is to obtain the
most accurate evaluations of the aggregated risks distribution and risk
measures when working on financial or insurance data under the presence of
heavy tail and to provide practical solutions for accurately estimating high
quantiles of aggregated risks. We explore a new method, called Normex, to
handle this problem numerically as well as theoretically, based on properties
of upper order statistics. Normex provides accurate results, only weakly
dependent upon the sample size and the tail index. We compare it with existing
methods.


title: Zariski topologies on stratified spectra of quantum algebras

abstract:
  A framework is developed to describe the Zariski topologies on the prime and
primitive spectra of a quantum algebra $A$ in terms of the (known) topologies
on strata of these spaces and maps between the collections of closed sets of
different strata. A conjecture is formulated, under which the desired maps
would arise from homomorphisms between certain central subalgebras of localized
factor algebras of $A$. When the conjecture holds, spec $A$ and prim $A$ are
then determined, as topological spaces, by a finite collection of (classical)
affine algebraic varieties and morphisms between them. The conjecture is
verified for ${\cal O}_q(GL_2(k))$, ${\cal O}_q(SL_3(k))$, and ${\cal
O}_q(M_2(k))$ when $q$ is a non-root of unity and the base field $k$ is
algebraically closed.


title:
Use of checkpoint-restart for complex HEP software on traditional
  architectures and Intel MIC

abstract:
  Process checkpoint-restart is a technology with great potential for use in
HEP workflows. Use cases include debugging, reducing the startup time of
applications both in offline batch jobs and the High Level Trigger, permitting
job preemption in environments where spare CPU cycles are being used
opportunistically and efficient scheduling of a mix of multicore and
single-threaded jobs. We report on tests of checkpoint-restart technology using
CMS software, Geant4-MT (multi-threaded Geant4), and the DMTCP (Distributed
Multithreaded Checkpointing) package. We analyze both single- and
multi-threaded applications and test on both standard Intel x86 architectures
and on Intel MIC. The tests with multi-threaded applications on Intel MIC are
used to consider scalability and performance. These are considered an indicator
of what the future may hold for many-core computing.


title: Quantum-Limited Amplification via Reservoir Engineering

abstract:
  We describe a new kind of phase-preserving quantum amplifier which utilizes
dissipative interactions in a parametrically-coupled three-mode bosonic system.
The use of dissipative interactions provides a fundamental advantage over
standard cavity-based parametric amplifiers: large photon number gains are
possible with quantum-limited added noise, with no limitation on the
gain-bandwidth product. We show that the scheme is simple enough to be
implemented both in optomechanical systems and in superconducting microwave
circuits.


title:
Nearly Optimal Sample Size in Hypothesis Testing for High-Dimensional
  Regression

abstract:
  We consider the problem of fitting the parameters of a high-dimensional
linear regression model. In the regime where the number of parameters $p$ is
comparable to or exceeds the sample size $n$, a successful approach uses an
$\ell_1$-penalized least squares estimator, known as Lasso. Unfortunately,
unlike for linear estimators (e.g., ordinary least squares), no
well-established method exists to compute confidence intervals or p-values on
the basis of the Lasso estimator. Very recently, a line of work
\cite{javanmard2013hypothesis, confidenceJM, GBR-hypothesis} has addressed this
problem by constructing a debiased version of the Lasso estimator. In this
paper, we study this approach for random design model, under the assumption
that a good estimator exists for the precision matrix of the design. Our
analysis improves over the state of the art in that it establishes nearly
optimal \emph{average} testing power if the sample size $n$ asymptotically
dominates $s_0 (\log p)^2$, with $s_0$ being the sparsity level (number of
non-zero coefficients). Earlier work obtains provable guarantees only for much
larger sample size, namely it requires $n$ to asymptotically dominate $(s_0
\log p)^2$.
  In particular, for random designs with a sparse precision matrix we show that
an estimator thereof having the required properties can be computed
efficiently. Finally, we evaluate this approach on synthetic data and compare
it with earlier proposals.

categories: math.ST cs.IT cs.LG math.IT stat.ME stat.TH


title: Quantifying Coherence

abstract:
  We introduce a rigorous framework for the quantification of coherence and
identify intuitive and easily computable measures of coherence. We achieve this
by adopting the viewpoint of coherence as a physical resource. By determining
defining conditions for measures of coherence we identify classes of
functionals that satisfy these conditions and other, at first glance natural
quantities, that do not qualify as coherence measure. We conclude with an
outline of the questions that remain to be answered to complete the theory of
coherence as a resource.


title:
B-meson decay constants with domain-wall light quarks and
  nonperturbatively tuned relativistic b-quarks

abstract:
  We report on our progress to obtain the decay constants f_B and f_Bs from
lattice-QCD simulations on the RBC-UKQCD Collaborations 2+1 flavor domain-wall
Iwasaki lattices. Using domain-wall light quarks and relativistic b-quarks we
analyze data with several partially quenched light-quark masses at two lattice
spacings of a approx 0.11 fm and a approx 0.08 fm.


title: An Introduction to Topological Quantum Codes

abstract:
  This is the chapter \emph{Topological Codes} of the book \emph{Quantum Error
Correction}, edited by Daniel A. Lidar and Todd A. Brun, Cambridge University
Press, New York, 2013.
  http://www.cambridge.org/us/academic/subjects/physics/quantum-physics-quantum-information-and-quantum-computation/quantum-error-correction


title: Unipotent and Nakayama automorphisms of quantum nilpotent algebras

abstract:
  Automorphisms of algebras $R$ from a very large axiomatic class of quantum
nilpotent algebras are studied using techniques from noncommutative unique
factorization domains and quantum cluster algebras. First, the Nakayama
automorphism of $R$ (associated to its structure as a twisted Calabi-Yau
algebra) is determined and shown to be given by conjugation by a normal
element, namely, the product of the homogeneous prime elements of $R$ (there
are finitely many up to associates). Second, in the case when $R$ is connected
graded, the unipotent automorphisms of $R$ are classified up to minor
exceptions. This theorem is a far reaching extension of the classification
results [20, 22] previously used to settle the Andruskiewitsch--Dumas and
Launois--Lenagan conjectures. The result on unipotent automorphisms has a wide
range of applications to the determination of the full automorphisms groups of
the connected graded algebras in the family. This is illustrated by a uniform
treatment of the automorphism groups of the generic algebras of quantum
matrices of both rectangular and square shape [13, 20].


title:
Centrality dependence of the direct photon yield and elliptic flow in
  heavy-ion collisions at sqrt(s)=200 GeV

abstract:
  We calculate the centrality dependence of direct photons produced in Au+Au
collisions at sqrt{s}=200GeV and their transverse momentum spectra within the
Parton-Hadron-String Dynamics (PHSD) transport approach. As sources for
'direct' photons, we incorporate the interactions of quarks and gluons as well
as hadronic interactions (pi+pi->rho+gamma, rho+pi->pi+gamma, meson-meson
bremsstrahlung m+m->m+m+gamma, meson-baryon bremsstrahlung m+B->m+B+gamma), the
decays of phi and a_1 mesons and the photons produced in the initial hard
collisions ('pQCD'). We find that the pT spectra of the 'thermal' photons (i.e.
the direct photons after the pQCD contribution is subtracted) deviate from
exponential distributions and, consequently, observe a strong dependence of the
inverse slope parameter T_eff on the fitting range in pT. On the other hand,
all the obtained 'effective temperatures' are well above the critical
temperature for the deconfinement phase transition even for peripheral
collisions, reflecting primarily a 'blue shift' due to radial collective motion
of hadrons. Our calculations suggest that the channel decomposition of the
observed spectrum changes with centrality with an increasing (dominant)
contribution of hadronic sources for more peripheral reactions. Furthermore,
the thermal photon yield is found to scale roughly with the number of
participant nucleons as N_part^alpha with alpha=1.5, whereas the partonic
contribution scales with an exponent alpha_p=1.75. Additionally, we provide
predictions for the centrality dependence of the direct photon elliptic flow
v_2(pT). The direct photon $v_2$ is seen to be larger in peripheral collisions
compared to the most central ones since the photons from the hot deconfined
matter in the early stages of the collision carry a much smaller elliptic flow
than the final hadrons.


title:
The TRENDS High-Contrast Imaging Survey. V. Discovery of an Old and Cold
  Benchmark T-dwarf Orbiting the Nearby G-star HD 19467

abstract:
  The nearby Sun-like star HD 19467 shows a subtle radial velocity (RV)
acceleration of -1.37+/-0.09 m/s/yr over an 16.9 year time baseline (an RV
trend), hinting at the existence of a distant orbiting companion. We have
obtained high-contrast adaptive optics images of the star using NIRC2 at Keck
Observatory and report the direct detection of the body that causes the
acceleration. The companion, HD 19467 B, is dK=12.57+/-0.09 mag fainter than
its parent star (contrast ratio of 9.4e-6), has blue colors J-K_s=-0.36+/-0.14
(J-H=-0.29+/-0.15), and is separated by 1.653+/-0.004" (51.1+/-1.0 AU).
Follow-up astrometric measurements obtained over an 1.1 year time baseline
demonstrate physical association through common parallactic and proper motion.
We calculate a firm lower-limit of m>51.9^{+3.6}_{-4.3}Mjup for the companion
mass from orbital dynamics using a combination of Doppler observations and
imaging. We estimate a model-dependent mass of m=56.7^{+4.6}_{-7.2}Mjup from a
gyrochronological age of 4.3^{+1.0}_{-1.2} Gyr. Isochronal analysis suggests a
much older age of $9\pm1$ Gyr, which corresponds to a mass of
m=67.4^{+0.9}_{-1.5}Mjup. HD 19467 B's measured colors and absolute magnitude
are consistent with a late T-dwarf [~T5-T7]. We may infer a low metallicity of
[Fe/H]=-0.15+/-0.04 for the companion from its G3V parent star. HD 19467 B is
the first directly imaged benchmark T-dwarf found orbiting a Sun-like star with
a measured RV acceleration.


title:
Bispectrum of cosmological density perturbations in the most general
  second-order scalar-tensor theory

abstract:
  We study the bispectrum of the matter density perturbations induced by the
large scale structure formation in the most general second-order scalar-tensor
theory that may possess the Vainshtein mechanism as a screening mechanism. On
the basis of the standard perturbation theory, we derive the bispectrum being
expressed by a kernel of the second order of the density perturbations. We find
that the kernel at the leading order is characterized by one parameter, which
is determined by the solutions of the linear density perturbations, the Hubble
parameter and the other function specifying nonlinear interactions. This does
not allow for varied behavior in the bispectrum of the matter density
perturbations in the most general second-order scalar-tensor theory equipped
with the Vainshtein mechanism. We exemplify the typical behavior of the
bispectrum in a kinetic gravity braiding model.


title: Sterile neutrino dark matter bounds from galaxies of the Local Group

abstract:
  We show that the canonical oscillation-based (non-resonant) production of
sterile neutrino dark matter is inconsistent at $>99$% confidence with
observations of galaxies in the Local Group. We set lower limits on the
non-resonant sterile neutrino mass of $2.5$ keV (equivalent to $0.7$ keV
thermal mass) using phase-space densities derived for dwarf satellite galaxies
of the Milky Way, as well as limits of $8.8$ keV (equivalent to $1.8$ keV
thermal mass) based on subhalo counts of $N$-body simulations of M 31
analogues. Combined with improved upper mass limits derived from significantly
deeper X-ray data of M 31 with full consideration for background variations, we
show that there remains little room for non-resonant production if sterile
neutrinos are to explain $100$% of the dark matter abundance. Resonant and
non-oscillation sterile neutrino production remain viable mechanisms for
generating sufficient dark matter sterile neutrinos.


title: Top Quark Production

abstract:
  I discuss top quark production in hadronic collisions. I present the
soft-gluon resummation formalism and its derivation from factorization and
renormalization-group evolution, and two-loop calculations of soft anomalous
dimensions in the eikonal approximation. I discuss the contributions of
next-to-next-to-leading order (NNLO) soft-gluon corrections to the total cross
sections and top-quark transverse momentum and rapidity distributions for
top-antitop pair production, and for single-top production in the $t$ and $s$
channels and in association with a $W$ boson or a charged Higgs boson.


title:
The ATLAS$^{\rm{3D}}$ project - XXV: Two-dimensional kinematic analysis
  of simulated galaxies and the cosmological origin of fast and slow rotators

abstract:
  We present a detailed two-dimensional stellar dynamical analysis of a sample
of 44 cosmological hydrodynamical simulations of individual central galaxies
and their satellites. Kinematic maps of the stellar line-of-sight velocity,
velocity dispersion, and higher-order Gauss-Hermite moments $h_3$ and $h_4$ are
constructed for each central galaxy and for the most massive satellites. The
amount of rotation is quantified using the $\lambda_{\mathrm{R}}$-parameter.
The velocity, velocity dispersion, $h_3$, and $h_4$ fields of the simulated
galaxies show a diversity similar to observed kinematic maps of early-type
galaxies in the ATLAS$^{\rm{3D}}$ survey. This includes fast (regular), slow,
and misaligned rotation, hot spheroids with embedded cold disk components as
well as galaxies with counter-rotating cores or central depressions in the
velocity dispersion. We link the present day kinematic properties to the
individual cosmological formation histories of the galaxies. In general, major
galaxy mergers have a significant influence on the rotation properties
resulting in both a spin-down as well as a spin-up of the merger remnant. Lower
mass galaxies with significant in-situ formation of stars, or with additional
gas-rich major mergers - resulting in a spin-up - in their formation history,
form elongated fast rotators with a clear anti-correlation of $h_3$ and
$v/\sigma$. An additional formation path for fast rotators includes gas poor
major mergers leading to a spin-up of the remnants. This formation path does
not result in anti-correlated $h_3$ and $v/\sigma$. The galaxies most
consistent with the rare class of non-rotating round early-type galaxies grow
by gas-poor minor mergers alone. In general, more massive galaxies have less
in-situ star formation since $z \sim 2$, rotate slower and have older stellar
populations. (shortened)


title:
The Partially-Split Hall Bar: Tunneling in the Bosonic Integer Quantum
  Hall Effect

abstract:
  We study point-contact tunneling in the integer quantum Hall state of bosons.
This symmetry-protected topological state has electrical Hall conductivity
equal to $2 e^2/h$ and vanishing thermal Hall conductivity. In contrast to the
integer quantum Hall state of fermions, a point contact can have a dramatic
effect on the low energy physics. In the absence of disorder, a point contact
generically leads to a partially-split Hall bar geometry. We describe the
resulting intermediate fixed point via the two-terminal electrical (Hall)
conductance of the edge modes. Disorder along the edge, however, both restores
the universality of the two-terminal conductance and helps preserve the
integrity of the Hall bar within the relevant parameter regime.


title: Matching Fully Differential NNLO Calculations and Parton Showers

abstract:
  We present a general method to match fully differential
next-to-next-to-leading (NNLO) calculations to parton shower programs. We
discuss in detail the perturbative accuracy criteria a complete NNLO+PS
matching has to satisfy. Our method is based on consistently improving a given
NNLO calculation with the leading-logarithmic (LL) resummation in a chosen jet
resolution variable. The resulting NNLO$+$LL calculation is cast in the form of
an event generator for physical events that can be directly interfaced with a
parton shower routine, and we give an explicit construction of the input "Monte
Carlo cross sections" satisfying all required criteria. We also show how other
proposed approaches naturally arise as special cases in our method.


title:
The energy production rate density of cosmic rays in the local universe
  is $\sim10^{44-45}\rm erg~Mpc^{-3}~yr^{-1}$ at all particle energies

abstract:
  The energy output (per logarithmic interval of particle energies) of Cosmic
Rays (CRs) with energies $10{\rm GeV}\lesssim\varepsilon_p\lesssim100{\rm GeV}$
is $\sim 10^{47}\rm erg$ per solar mass of star$-$formation, based on the CR
production rate in the Milky Way and in starburst galaxies, implying a
generation rate of $\varepsilon_p^2Q\sim 10^{45}\rm erg~Mpc^{-3}~yr^{-1}$ in
the local universe. It is only $\sim 10$ times larger than the output,
$\varepsilon_p^2 Q=0.5\pm0.2\times 10^{44}\rm erg~Mpc^{-3}~yr^{-1}$, of Ultra
High Energy CRs (UHECRs) at energies $10^{10.5}{\rm
GeV}<\varepsilon_p<10^{12}\rm GeV$ (obtained assuming they are mostly protons),
which in turn is comparable to the lower limit of $\varepsilon_p^2 Q\ge
0.5\times 10^{44}\rm erg~Mpc^{-3}~yr^{-1}$ of high energy CRs with $10^6{\rm
GeV}\lesssim\varepsilon_p\lesssim 10^{8}\rm GeV$ implied by the saturation of
the Waxman-Bahcall bound by the neutrino excess recently discovered by IceCube.
These similarities are consistent with a flat production spectrum,
$\varepsilon_p^2 Q\sim \text{const}$ for CRs at all observed energies. If a
flat production spectrum is generated by our galaxy, the observed CR flux in
the range $10^{6.5}-10^{9.5}\rm GeV$, above the "knee", is suppressed compared
to lower energies due to propagation effects rather than acceleration upper
limits. As suggested by Parizot and Aublin, the most exciting possibility is
that cosmic rays at all energies are emitted from a single type of (unknown)
sources, which can not be supernova remnants.


title: Superfluid Spin Transport through Easy-Plane Ferromagnetic Insulators

abstract:
  Superfluid spin transport $-$ dissipationless transport of spin $-$ is
theoretically studied in a ferromagnetic insulator with easy-plane anisotropy.
We consider an open geometry where spin current is injected into the
ferromagnet from one side by a metallic reservoir with a nonequilibrium spin
accumulation, and ejected into another metallic reservoir located downstream.
Spin transport through the device is studied using a combination of
magnetoelectric circuit theory, Landau-Lifshitz-Gilbert phenomenology, and
microscopic linear-response theory. We discuss how spin superfluidity can be
probed using a magnetically-mediated electron-drag experiment.


title: Extrinsic Ricci Flow on Surfaces of Revolution

abstract:
  An extrinsic representation of a Ricci flow on a differentiable n-manifold M
is a family of submanifolds S(t), each smoothly embedded in R^{n+k}, evolving
as a function of time t such that the metrics induced on the submanifolds S(t)
by the ambient Euclidean metric yield the Ricci flow on M. When does such a
representation exist?
  We formulate this question precisely and describe a new, comprehensive way of
addressing it for surfaces of revolution in R^3. Of special interest is the
Ricci flow on a toroidal surface of revolution, that is, a surface of
revolution whose profile curve is an immersed curve which does not intersect
the axis of revolution. In In this case, the extrinsic representation of the
Ricci flow on a Riemannian cover of S is eternal. This flow can also be
realized as a compact family of non-smooth, but isometric, embeddings of the
torus into R^3.


title:
Single-Field Consistency Relations of Large Scale Structure. Part II:
  Resummation and Redshift Space

abstract:
  We generalize the recently derived single-field consistency relations of
Large Scale Structure in two directions. First, we treat the effect of the long
modes (with momentum q) on the short ones (with momentum k) non-perturbatively,
by writing resummed consistency relations which do not require k/q \delta_q <<
1. These relations do not make any assumptions on the short-scales physics and
are extended to include (an arbitrary number of) multiple long modes, internal
lines with soft momenta and soft loops. We do several checks of these relations
in perturbation theory and we verify that the effect of soft modes always
cancels out in equal-time correlators. Second, we write the relations directly
in redshift space, without assuming the single-stream approximation: not only
the long mode affects the short scales as a homogeneous gravitational field,
but it also displaces them by its velocity along the line-of-sight. Redshift
space consistency relations still vanish when short modes are taken at equal
time: an observation of a signal in the squeezed limit would point towards
multifield inflation or a violation of the equivalence principle.


title: Improved Precision in Estimating Average Treatment Effects

abstract:
  The Average Treatment Effect (ATE) is a global measure of the effectiveness
of an experimental treatment intervention. Classical methods of its estimation
either ignore relevant covariates or do not fully exploit them. Moreover, past
work has considered covariates as fixed. We present a method for improving the
precision of the ATE estimate: the treatment and control responses are
estimated via a regression, and information is pooled between the groups to
produce an asymptotically unbiased estimate; we subsequently justify the random
X paradigm underlying the result. Standard errors are derived, and the
estimator's performance is compared to the traditional estimator. Conditions
under which the regression-based estimator is preferable are detailed, and a
demonstration on real data is presented.


title:
Runaway greenhouse effect on exomoons due to irradiation from hot, young
  giant planets

abstract:
  The Kepler space telescope has detected transits of objects as small as the
Earth's Moon, and moons as small as 0.2 Earth masses can be detected in the
Kepler data by transit timing and transit duration variations of their host
planets. Such massive moons around giant planets in the stellar habitable zone
(HZ) could serve as habitats for extraterrestrial life. We here assess the
danger of exomoons to be in a runaway greenhouse (RG) state due to extensive
heating from the planet. We apply pre-computed evolution tracks for giant
planets to calculate the incident planetary radiation on the moon as a function
of time. The total energy budget of stellar flux, illumination from the planet,
and tidal heating in the satellite is compared to the critical flux for the
moon to experience an RG effect. Irradiation from a 13-Jupiter-mass planet onto
an Earth-sized moon at a distance of ten Jupiter radii can drive an RG state on
the moon for about 200 Myr. If stellar illumination equivalent to that received
by Earth from the Sun is added, the RG holds for about 500 Myr. After 1000 Myr,
the planet's habitable edge has moved inward to about 6 planetary radii.
Exomoons in orbits with eccentricities of 0.1 experience strong tidal heating;
they must orbit a 13-Jupiter-mass host beyond 29 or 18 Jupiter radii after 100
Myr (at the inner and outer boundaries of the stellar HZ, respectively), and
beyond 13 Jupiter radii (in both cases) after 1000 Myr to be habitable. If a
roughly Earth-sized moon would be detected in orbit around a giant planet, and
if this binary would orbit in the stellar HZ, then it will be crucial to
recover the moon's orbital history. If such a moon around a 13-Jupiter-mass
planet has been closer than 20 Jupiter radii to its host during the first few
hundred million years at least, then it might have lost substantial amounts of
its initial water reservoir and be uninhabitable today.


title: Pebbling Arguments for Tree Evaluation

abstract:
  The Tree Evaluation Problem was introduced by Cook et al. in 2010 as a
candidate for separating P from L and NL. The most general space lower bounds
known for the Tree Evaluation Problem require a semantic restriction on the
branching programs and use a connection to well-known pebble games to generate
a bottleneck argument. These bounds are met by corresponding upper bounds
generated by natural implementations of optimal pebbling algorithms. In this
paper we extend these ideas to a variety of restricted families of both
deterministic and non-deterministic branching programs, proving tight lower
bounds under these restricted models. We also survey and unify known lower
bounds in our "pebbling argument" framework.


title:
Long-Lived Complexes, Ergodicity and Chaos in Ultracold Molecular
  Collisions

abstract:
  Estimates for the lifetime of collision complexes formed during ultracold
molecular collisions based on density-of-states arguments are shown to be
consistent with similar estimate based on classical trajectory calculations. In
the classical version, these collisions are shown to exhibit chaos, and their
fractal dimensions are calculated versus collision energy. From these results,
a picture emerges that ultracold collisions are classically ergodic, justifying
the density-of-states estimates for lifetimes. These results point the way
toward using the techniques of classical and quantum chaos to interpret
molecular collisions in the ultracold regime.


title:
Strong enhancement of bulk superconductivity by engineered
  nanogranularity

abstract:
  It is now well established, both theoretically and experimentally, that very
small changes in the size of isolated nanograins lead to substantial
nonmonotonic variations, and sometimes enhancement, of the mean-field
spectroscopic gap of conventional superconductors. A natural question to ask,
of broad relevance for the theory and applications of superconductivity, is
whether these size effects can also enhance the critical temperature of a bulk
granular material composed of such nanograins. Here we answer this question
affirmatively. We combine mean-field, semiclassical, and percolation techniques
to show that engineered nanoscale granularity in conventional superconductors
can enhance the critical temperature by up to a few times compared to the
nongranular bulk limit. This prediction is valid for three-dimensional and also
quasi-two-dimensional samples, provided the thickness is much larger than the
grain size. Our model takes into account an experimentally realistic
distribution of grain sizes in the array, charging effects, tunnelling by
quasiparticles, and limitations related to the proliferation of thermal
fluctuations for sufficiently small grains.


title:
Coagulation Calculations of Icy Planet Formation Around 0.1--0.5~\msun\
  Stars: Super-Earths From Large Planetestimals

abstract:
  We investigate formation mechanisms for icy super-Earth mass planets orbiting
at 2-20 AU around 0.1-0.5 solar mass stars. A large ensemble of coagulation
calculations demonstrates a new formation channel: disks composed of large
planetesimals with radii of 30-300 km form super-Earths on time scales of
roughly 1 Gyr. In other gas-poor disks, a collisional cascade grinds
planetesimals to dust before the largest planets reach super-Earth masses. Once
icy Earth-mass planets form, they migrate through the leftover swarm of
planetesimals at rates of 0.01-1 AU per Myr. On time scales of 10 Myr to 1 Gyr,
many of these planets migrate through the disk of leftover planetesimals from
semimajor axes of 5-10 AU to 1-2 AU. A few per cent of super-Earths might
migrate to semimajor axes of 0.1-0.2 AU. When the disk has an initial mass
comparable with the minimum mass solar nebula scaled to the mass of the central
star, the predicted frequency of super-Earths matches the observed frequency.


title: Metric axioms: a structural study

abstract:
  For a fixed set $X$, an arbitrary \textit{weight structure} $d \in
[0,\infty]^{X \times X}$ can be interpreted as a distance assignment between
pairs of points on $X$. Restrictions (i.e. \textit{metric axioms}) on the
behaviour of any such $d$ naturally arise, such as separation, triangle
inequality and symmetry. We present an order-theoretic investigation of various
collections of weight structures, as naturally occurring subsets of
$[0,\infty]^{X \times X}$ satisfying certain metric axioms. Furthermore, we
exploit the categorical notion of adjunctions when investigating connections
between the above collections of weight structures. As a corollary, we present
several lattice-embeddability theorems on a well-known collection of weight
structures on $X$.


title:
Charge, spin and lattice effects in the spin-Peierls ground state of
  MEM(TCNQ)$_2$

abstract:
  We report an investigation of charge, spin and lattice effects in the
spin-Peierls state of the organic compound MEM(TCNQ)$_2$. The 16.5 GHz
dielectric function along the chain axis shows an enhancement below the
spin-Peierls transition temperature near 18 K consistent with the charge
coupling to the elastic strain involved in the transition. The velocity of two
elastic modes perpendicular to the chain axis presents anomalies at the
transition which can be explained with a Landau free energy model including a
linear-quadratic coupling energy term between the appropriate elastic strain
$e$ and the spin-Peierls magnetic gap $\Delta_q$. The analysis of the
dielectric and elastic features aims toward an order parameter with an
associated critical exponent $\beta \sim$ 0.36, which is similar to the
three-dimensional behavior seen in other spin-Peierls materials. All these
effects studied in a magnetic field up to 18 Teslas appear also compatible with
a mean-field model of a quasi-one-dimensional spin-Peierls system.


title:
New Particles Working Group Report of the Snowmass 2013 Community Summer
  Study

abstract:
  This report summarizes the work of the Energy Frontier New Physics working
group of the 2013 Community Summer Study (Snowmass).


title: Every Lipschitz metric has $C^1$-geodesics

abstract:
  We prove that the geodesic equation for any semi-Riemannian metric of
regularity $C^{0,1}$ possesses $C^1$-solutions in the sense of Filippov.


title:
The Kato Square Root Problem follows from an Extrapolation Property of
  the Laplacian

abstract:
  On a domain $\Omega \subseteq \mathbb{R}^d$ we consider second order elliptic
systems in divergence form with bounded complex coefficients, realized via a
sesquilinear form with domain $V \subseteq H^1(\Omega)$. Under very mild
assumptions on $\Omega$ and $V$ we show that the Kato Square Root Problem for
such systems can be reduced to a regularity result for the fractional powers of
the negative Laplacian in the same geometric setting. This extends an earlier
result of McIntosh to non-smooth coefficients.


title: The Kato Square Root Problem for Mixed Boundary Conditions

abstract:
  We consider the negative Laplacian subject to mixed boundary conditions on a
bounded domain. We prove under very general geometric assumptions that slightly
above the critical exponent $\frac{1}{2}$ its fractional power domains still
coincide with suitable Sobolev spaces of optimal regularity. In combination
with a reduction theorem recently obtained by the authors, this solves the Kato
Square Root Problem for elliptic second order operators and systems in
divergence form under the same geometric assumptions.


title: Easton functions and supercompactness

abstract:
  Suppose $\kappa$ is $\lambda$-supercompact witnessed by an elementary
embedding $j:V\rightarrow M$ with critical point $\kappa$, and further suppose
that $F$ is a function from the class of regular cardinals to the class of
cardinals satisfying the requirements of Easton's theorem: (1) $\forall\alpha$
$\alpha<\textrm{cf}(F(\alpha))$ and (2) $\alpha<\beta$ $\Longrightarrow$
$F(\alpha)\leq F(\beta)$. In this article we address the question: assuming
GCH, what additional assumptions are necessary on $j$ and $F$ if one wants to
be able to force the continuum function to agree with $F$ globally, while
preserving the $\lambda$-supercompactness of $\kappa$?
  We show that, assuming GCH, if $F$ is any function as above, and in addition
for some regular cardinal $\lambda>\kappa$ there is an elementary embedding
$j:V\rightarrow M$ with critical point $\kappa$ such that $\kappa$ is closed
under $F$, the model $M$ is closed under $\lambda$-sequences,
$H(F(\lambda))\subseteq M$, and for each regular cardinal $\gamma\leq \lambda$
one has $(|j(F)(\gamma)|=F(\gamma))^V$, then there is a cardinal-preserving
forcing extension in which $2^\delta=F(\delta)$ for every regular cardinal
$\delta$ and $\kappa$ remains $\lambda$-supercompact. This answers a question
of B. Cody, M. Magidor, On supercompactness and the continuum function, Ann.
Pure Appl. Logic, (2013).


title: High-energy QCD amplitudes at two loops and beyond

abstract:
  Recent progress in our understanding of infrared singularities of
multi-parton amplitudes has shown that the simplest form of Regge factorization
for high-energy gauge-theory amplitudes fails starting at
next-to-next-to-leading logarithmic accuracy. We provide a framework to
organize the calculation of parton amplitudes at leading power in t/s, in terms
of factorizing and non-factorizing contributions. This allows us to give
explicit expressions for the leading Reggeization-breaking terms in two-loop
and three-loop quark and gluon amplitudes in QCD. In particular, using only
infrared information, we recover a known non-factorizing, non-logarithmic
double-pole contribution at two-loops, and we compute the leading
non-factorizing single-logarithmic contributions at three loops.


title: Highly Effective Actions

abstract:
  It is conjectured that the world-volume action of a probe D3-brane in an
$AdS_5 \times S^5$ background of type IIB superstring theory, with one unit of
flux, can be reinterpreted as the exact effective action (or highly effective
action) for U(2), ${\cal N} = 4$ super Yang-Mills theory on the Coulomb branch.
An analogous conjecture for $U(2)_k \times U(2)_{-k} $ ABJM theory is also
presented. The main evidence supporting these conjectures is that the brane
actions have all of the expected symmetries and dualities. Highly effective
actions have general coordinate invariance, even though they describe
nongravitational theories.


title: The relativistic causal Newton gravity law vs general relativity

abstract:
  The equations of the relativistic causal Newton gravity law for the planets
of the solar system are studied in the approximation when the Sun rests at the
coordinate origin and the planets do not interact between each other. The
planet orbits of general relativity are also studied in the same approximation.


title: Shared kernel Bayesian screening

abstract:
  This article concerns testing for equality of distribution between groups. We
focus on screening variables with shared distributional features such as common
support, modes and patterns of skewness. We propose a Bayesian testing method
using kernel mixtures, which improves performance by borrowing information
across the different variables and groups through shared kernels and a common
probability of group differences. The inclusion of shared kernels in a finite
mixture, with Dirichlet priors on the weights, leads to a simple framework for
testing that scales well for high-dimensional data. We provide closed
asymptotic forms for the posterior probability of equivalence in two groups and
prove consistency under model misspecification. The method is applied to DNA
methylation array data from a breast cancer study, and compares favorably to
competitors when type I error is estimated via permutation.


title:
Coupling of magnetic order to planar Bi electrons in the anisotropic
  Dirac metals AMnBi2 (A = Sr, Ca)

abstract:
  We report powder and single crystal neutron diffraction measurements of the
magnetic order in AMnBi2 (A = Sr and Ca), two layered manganese pnictides with
anisotropic Dirac fermions on a Bi square net. Both materials are found to
order at TN approx 300 K in k = 0 antiferromagnetic structures, with ordered Mn
moments at T = 10 K of approximately 3.8 muB aligned along the c axis. The
magnetic structures are Neel-type within the Mn--Bi layers but the inter-layer
ordering is different, being antiferromagnetic in SrMnBi2 and ferromagnetic in
CaMnBi2. This allows a mean-field coupling of the magnetic order to Bi
electrons in CaMnBi2 but not in SrMnBi2. We find clear evidence that magnetic
order influences electrical transport. First principles calculations explain
the experimental observations and suggest that the mechanism for different
inter-layer ordering in the two compounds is the competition between the
anteiferromagnetic superexchange and ferromagnetic double exchange carried by
itinerant Bi electrons.


title: Quantum polydisk, quantum ball, and a q-analog of Poincar\'e's theorem

abstract:
  The classical Poincar\'e theorem (1907) asserts that the polydisk $\mathbb
D^n$ and the ball $\mathbb B^n$ in $\mathbb C^n$ are not biholomorphically
equivalent for $n\ge 2$. Equivalently, this means that the Fr\'echet algebras
$\mathcal O(\mathbb D^n)$ and $\mathcal O(\mathbb B^n)$ of holomorphic
functions are not topologically isomorphic. Our goal is to prove a
noncommutative version of the above result. Given $q\in\mathbb C\setminus\{
0\}$, we define two noncommutative power series algebras $\mathcal O_q(\mathbb
D^n)$ and $\mathcal O_q(\mathbb B^n)$, which can be viewed as $q$-analogs of
$\mathcal O(\mathbb D^n)$ and $\mathcal O(\mathbb B^n)$, respectively. Both
$\mathcal O_q(\mathbb D^n)$ and $\mathcal O_q(\mathbb B^n)$ are the completions
of the algebraic quantum affine space $\mathcal O_q^{\mathrm{reg}}(\mathbb
C^n)$ w.r.t. certain families of seminorms. In the case where $0<q<1$, the
algebra $\mathcal O_q(\mathbb B^n)$ admits an equivalent definition related to
L. L. Vaksman's algebra of continuous functions on the closed quantum ball. We
show that both $\mathcal O_q(\mathbb D^n)$ and $\mathcal O_q(\mathbb B^n)$ can
be interpreted as Fr\'echet algebra deformations (in a suitable sense) of
$\mathcal O(\mathbb D^n)$ and $\mathcal O(\mathbb B^n)$, respectively. Our main
result is that $\mathcal O_q(\mathbb D^n)$ and $\mathcal O_q(\mathbb B^n)$ are
not isomorphic if $n\ge 2$ and $|q|=1$, but are isomorphic if $|q|\ne 1$.


title:
SN 2010lp---a Type Ia supernova from a violent merger of two
  carbon--oxygen White Dwarfs

abstract:
  SN 2010lp is a subluminous Type Ia supernova (SN Ia) with slowly-evolving
lightcurves. Moreover, it is the only subluminous SN Ia observed so far that
shows narrow emission lines of OI in late-time spectra, indicating unburned
oxygen close to the centre of the ejecta. Most explosion models for SNe Ia
cannot explain the narrow OI emission. Here, we present hydrodynamic explosion
and radiative transfer calculations showing that the violent merger of two
carbon-oxygen white dwarfs of 0.9 and 0.76 solar masses, respectively,
adequately reproduces the early-time observables of SN 2010lp. Moreover, our
model predicts oxygen close to the centre of the explosion ejecta, a
pre-requisite for narrow OI emission in nebular spectra as observed in SN
2010lp.


title: Warm molecular hydrogen in outflows from Ultraluminous Infrared Galaxies

abstract:
  Ultraluminous infrared galaxies (ULIRGs) show on average three times more
emission in the rotational transitions of molecular hydrogen than expected
based on their star formation rates. Using Spitzer archival data we investigate
the origin of excess warm H_2 emission in 115 ULIRGs of the IRAS 1 Jy sample.
We find a strong correlation between H_2 and [FeII] line luminosities,
suggesting that excess H_2 is produced in shocks propagating within neutral or
partially ionized medium. This view is supported by the correlations between
H_2 and optical line ratios diagnostic of such shocks. The galaxies powered by
star formation and those powered by active nuclei follow the same relationship
between H_2 and [FeII], with emission line width being the major difference
between these classes (about 500 and 1000 km/sec, respectively). We conclude
that excess H_2 emission is produced as the supernovae and active nuclei drive
outflows into the neutral interstellar medium of the ULIRGs. A weak positive
correlation between H_2 and the length of the tidal tails indicates that these
outflows are more likely to be encountered in more advanced mergers, but there
is no evidence for excess H_2 produced as a result of the collision shocks
during the final coalescence.


title: Performance of soft dielectric laminated composites

abstract:
  This paper contains a thorough investigation of the performance of
electrically activated layered soft dielectric composite actuators under plane
deformation. Noting that the activation can be induced controlling either the
voltage or the surface charge, the overall behaviour of the system is obtained
via homogenization at large strains taking either the macroscopic electric
field or the macroscopic electric displacement field as independent electrical
variable. The performance of a two-phase composite actuator compared to that of
the homogeneous case is highlighted for few boundary-value problems and for
different values of stiffness and permittivity ratios between constituents
being significant for applications, where the soft matrix is reinforced by a
relatively small volume fraction of a stiff and high-permittivity phase. For
charge-controlled devices, it is shown that some composite layouts admit, on
one hand, the occurrence of pull-in/snap-through instabilities that can be
exploited to design release-actuated systems, on the other, the possibility of
thickening at increasing surface charge density.


title:
Symmetry analysis of a class of autonomous even-order ordinary
  differential equations

abstract:
  A class of autonomous, even-order ordinary differential equations is
discussed from the point of view of Lie symmetries. It is shown that for a
certain power nonlinearity, the Noether symmetry group coincides with the Lie
point symmetry group. First integrals are established and exact solutions are
found. Furthermore, this paper complements, for the one-dimensional case, some
results in the literature of Lie group analysis of poliharmonic equations and
Noether symmetries obtained in the last twenty years. In particular, it is
shown that the exceptional negative power discovered in [A. H. Bokhari, F. M.
Mahomed and F. D. Zaman, Symmetries and integrability of a fourth-order
Euler-Bernoulli beam equation, J. Math. Phys., vol. 51, 053517, (2010)] is a
member of an one-parameter family of exceptional powers in which the Lie
symmetry group coincides with the Noether symmetry group.


title: Guaranteed sparse signal recovery with highly coherent sensing matrices

abstract:
  Compressive sensing is a methodology for the reconstruction of sparse or
compressible signals using far fewer samples than required by the Nyquist
criterion. However, many of the results in compressive sensing concern random
sampling matrices such as Gaussian and Bernoulli matrices. In common physically
feasible signal acquisition and reconstruction scenarios such as
super-resolution of images, the sensing matrix has a non-random structure with
highly correlated columns. Here we present a compressive sensing type recovery
algorithm, called Partial Inversion (PartInv), that overcomes the correlations
among the columns. We provide theoretical justification as well as empirical
comparisons.


title: An alternative formulation of the magnetostatic boundary value problem

abstract:
  We present an alternative formulation of the magnetostatic boundary value
problem which is useful for calculating the magnetic field around a magnetic
material placed in the vicinity of steady currents. The formulation differs
from the standard approach in that a single-valued scalar potential, plus a
vector field that depends on the given currents but not on the magnetic
material, are used to obtain the total magnetic field instead of a magnetic
vector potential. We illustrate the method by a few sample computations.


title: Variational formula for the time-constant of first-passage percolation

abstract:
  We consider first-passage percolation with positive, stationary-ergodic
weights on the square lattice $\mathbb{Z}^d$. Let $T(x)$ be the first-passage
time from the origin to a point $x$ in $\mathbb{Z}^d$. The convergence of the
scaled first-passage time $T([nx])/n$ to the time-constant as $n \to \infty$
can be viewed as a problem of homogenization for a discrete
Hamilton-Jacobi-Bellman (HJB) equation. We derive an exact variational formula
for the time-constant, and construct an explicit iteration that produces a
minimizer of the variational formula (under a symmetry assumption). We
explicitly identify when the iteration produces correctors.


title: Parsimonious Shifted Asymmetric Laplace Mixtures

abstract:
  A family of parsimonious shifted asymmetric Laplace mixture models is
introduced. We extend the mixture of factor analyzers model to the shifted
asymmetric Laplace distribution. Imposing constraints on the constitute parts
of the resulting decomposed component scale matrices leads to a family of
parsimonious models. An explicit two-stage parameter estimation procedure is
described, and the Bayesian information criterion and the integrated completed
likelihood are compared for model selection. This novel family of models is
applied to real data, where it is compared to its Gaussian analogue within
clustering and classification paradigms.


title: Creep dynamics of viscoelastic interfaces

abstract:
  The movement of a purely elastic interface driven on a disordered energy
potential is characterized by a depinning transition: when the pulling force S
is larger than some critical value S_1 the system is in a flowing regime and
moves at a finite velocity. If S < S_1 the interface remains pinned and its
velocity is zero. We show that for a one-dimensional interface, the inclusion
of viscoelastic relaxation produces the appearance of an intervening regime
between the pinned and the flowing phases in a well defined stress interval
S_0<S<S_1, in which the interface evolves through a sequence of avalanches that
give rise to a creep process. As S --> S_0 the creep velocity vanishes in an
universal way that is governed by a directed percolation process. As S --> S_1
the creep velocity increases as a power law due to the increase of the typical
size of the avalanches. The present observations may serve to improve the
understanding of fatigue failure mechanisms.


title: On the proton radius problem

abstract:
  The recent values of the proton charge radius obtained by means of
muonic-hydrogen laser spectroscopy are about $4\%$ different from the electron
scattering data. It has been suggested that the proton radius is actually
measured in different frames and that, starting from a non relativistic quark
model calculation, the Lorentz transformation of the form factors accounts
properly for the discepancy. We shall show that the relation between the charge
radii measured in different frames can be determined on very general grounds by
taking into account the Lorentz transformation of the charge density. In this
way, the discrepancy between muonic-hydrogen laser spectroscopy and electron
scattering data can be removed.


title: An Improved Solution for Restricted and Uncertain TRQ

abstract:
  CSPTRQ is an interesting problem and its has attracted much attention. The
CSPTRQ is a variant of the traditional PTRQ. As objects moving in a
constrained-space are common, clearly, it can also find many applications. At
the first sight, our problem can be easily tackled by extending existing
methods used to answer the PTRQ. Unfortunately, those classical techniques are
not well suitable for our problem, due to a set of new challenges. We develop
targeted solutions and demonstrate the efficiency and effectiveness of the
proposed methods through extensive experiments.


title:
Fabrication of high quality GaN nanopillar arrays by dry and wet
  chemical etching

abstract:
  We study strain relaxation and surface damage of GaN nanopillar arrays
fabricated using inductively coupled plasma (ICP) etching and post etch wet
chemical treatment. We controlled the shape and surface damage of such
nanopillar structures through selection of etching parameters. We compared
different substrate temperatures and different chlorine-based etch chemistries
to fabricate high quality GaN nanopillars. Room temperature photoluminescence
and Raman scattering measurements were carried to study the presence of surface
defect and strain relaxation on these nanostructures, respectively. We found
that wet KOH etching can remove the side wall damages caused by dry plasma
etching, leading to better quality of GaN nanopillars arrays. The Si material
underneath the GaN pillars was removed by KOH wet etching, leaving behind a
fine Si pillar to support the GaN structure. Substantial strain relaxations
were observed in these structures from room temperature Raman spectroscopy
measurements. Room temperature Photoluminescence spectroscopy shows the
presence of whispering gallery modes from these the nano disks structures.


title: Kaon Mixing Beyond the Standard Model

abstract:
  We report on an ongoing calculation of hadronic matrix elements needed to
parameterize K-Kbar mixing in generic BSM scenarios, using domain wall fermions
(DWF) at two lattice spacings. Recent work by the SWME collaboration shows a
significant disagreement with our previous results for two of these quantities.
Since the origin of this disagreement is unknown, it is important to reduce the
various uncertainties. In this work, we are using N_f=2+1 DWF with Iwasaki
gauge action at inverse lattice spacings of 2.31 and 1.75 GeV, with multiple
unitary pions on each ensemble, the lightest being 290 and 330 MeV on the finer
and coarser of the two ensembles respectively. This extends previous work by
the addition of a second lattice spacing (a^{-1}\approx 1.75 GeV).
Renormalization is carried out non-perturbatively in the RI/MOM scheme and
converted perturbatively to MSbar.


title:
Generalized Shannon-Khinchin Axioms and Uniqueness Theorem for
  Pseudo-additive Entropies

abstract:
  We consider the Shannon-Khinchin axiomatic systems for the characterization
of generalized entropies such as Sharma-Mital and Frank-Daffertshofer entropy.
We provide the generalization of Shannon-Khinchin axioms and give the
corresponding uniqueness theorem. The previous attempts at such axiomatizations
are also discussed.


title:
An axiomatic characterization of generalized entropies under analyticity
  condition

abstract:
  We present the characterization of the Nath, R\'enyi and
Havrda-Charv\'at-Tsallis entropies under the assumption that they are analytic
function with respect to the distribution dimension, unlike the the previous
characterizations, which supposes that they are expandable maximized for
uniform distribution.


title: Theory of $U(1)$ gauged Q-balls revisited

abstract:
  In this paper, the main properties of (3+1)-dimensional $U(1)$ gauged Q-balls
are examined. In particular, it is shown that the relation
$\frac{dE}{dQ}=\omega$ holds for such gauged Q-balls in the general case. As a
consequence, it is shown that the well-known estimate for the maximal charge of
stable gauged Q-balls was derived by means of an inconsistent procedure and can
not be considered as correct. A simple method for obtaining the main
characteristics of gauged Q-balls using only the nongauged background solution
for the scalar field in the case, when the back-reaction of the gauge field on
the scalar field is small and the linearized theory can be used, is proposed.
The criteria of applicability of the linearized theory, which do not reduce to
the demand of the smallness of the coupling constant, are established. Some
interesting properties of gauged Q-balls, as well as the advantages of the
proposed method, are demonstrated by the example of two models, admitting, in
the linear approximation in the perturbations, exact analytic solutions for
gauged Q-balls.


title:
Bounds for the Stieltjes Transform and the Density of States of Wigner
  Matrices

abstract:
  We consider ensembles of Wigner matrices, whose entries are (up to the
symmetry constraints) independent and identically distributed random variables.
We show the convergence of the Stieltjes transform towards the Stieltjes
transform of the semicircle law on optimal scales and with the optimal rate.
Our bounds improve previous results, in particular from [22,10], by removing
the logarithmic corrections. As applications, we establish the convergence of
the eigenvalue counting functions with the rate $(\log N)/N$ and the rigidity
of the eigenvalues of Wigner matrices on the same scale. These bounds improve
the results of [22,10,23].


title: Constructing Homogeneous Gorenstein Ideals

abstract:
  In 1983 Kustin and Miller introduced a construction of Gorenstein ideals in
local Gorenstein rings, starting from smaller such ideals. We review and modify
their construction in the case of graded rings and discuss it within the
framework of Gorenstein liaison theory. We determine invariants of the
constructed ideal. Concerning the problem of when a given Gorenstein ideal can
be obtained by the construction, we derive a necessary condition and exhibit a
Gorenstein ideal that can not be obtained using the construction.


title:
Planar Infinite-Horizon Optimal Control Problems with Weighted Average
  Cost and Constraints, Applied to Cheeger Sets

abstract:
  We establish a Poincar\`E-Bendixson type result for a weighted averaged
infinite horizon problem in the plane, with and without averaged constraints.
For the unconstrained problem, we establish the existence of a periodic optimal
solution, and for constrained problem, we establish the existence of an optimal
solution that alternates cyclicly between a finite number of periodic curves,
depending on the number of constraints. Applications of these results are
presented to the shape optimization problems of the Cheeger set and the
generalized Cheeger set, and also to a singular limit of the one-dimensional
Cahn-Hilliard equation