title: Making an ultracold gas

abstract:
  We provide an introduction to the experimental physics of quantum gases. At
the low densities of ultracold quantum gases, confinement can be understood
from single-particle physics, and interactions can be understood from two-body
physics. The structure of atoms provides resonances both in the optical domain
and in the radio-frequency domain. Atomic structure data is given for the 27
atomic isotopes that had been brought to quantum degeneracy at the time this
chapter was written. We discuss the motivations behind choosing among these
species. We review how static and oscillatory fields are treated
mathematically. An electric dipole moment can be induced in a neutral atom, and
is the basis for optical manipulation as well as short-range interactions. Many
atoms have permanent magnetic dipole moments, which can be used for trapping or
long-range interactions. The Toronto $^{40}$K/$^{87}$Rb lattice experiment
provides an illustration of how these tools are combined to create an
ultracold, quantum-degenerate gas.


title:
Transverse Singularities of Minimal Two-Valued Graphs in Arbitrary
  Codimension

abstract:
  We prove some epsilon regularity results for n-dimensional minimal two-valued
Lipschitz graphs. The main theorems imply uniqueness of tangent cones and
regularity of the singular set in a neighbourhood of any point at which at
least one tangent cone is equal to a pair of transversely intersecting
multiplicity one n-dimensional planes, and in a neighbourhood of any point at
which at which at least one tangent cone is equal to a union of four distinct
multiplicity one n-dimensional half-planes that meet along an (n-1) -
dimensional axis. The key ingredient is a new Excess Improvement Lemma obtained
via a blow-up method (inspired by the work of L. Simon on the singularities of
`multiplicity one' classes of minimal submanifolds) and which can be iterated
unconditionally. We also show that any tangent cone to an n-dimensional minimal
two-valued Lipschitz graph that is translation invariant along an (n-1) or
(n-2)- dimensional subspace is indeed a cone of one of the two aforementioned
forms, which yields a global decomposition result for the singular set


title: Metal-Insulator Transition in Graphene on Boron Nitride

abstract:
  Electrons in graphene aligned with hexagonal boron nitride are modelled by
Dirac fermions in a correlated random-mass landscape subject to a scalar- and
vector-potential disorder. We find that the system is insulating in the
commensurate phase since the average mass deviates from zero. At the transition
the mean mass is vanishing and electronic conduction in a finite sample can be
described by a critical percolation along zero-mass lines. In this case
graphene at the Dirac point is in a critical state with the conductivity
$\sqrt{3}e^2/h$. In the incommensurate phase the system behaves as a symplectic
metal.


title: Generating non-Rayleigh speckles with tailored intensity statistics

abstract:
  We experimentally generate speckle patterns with non-Rayleigh intensity
statistics using a phase-only spatial light modulator. By introducing high
order correlations to the input light fields we redistribute the intensity
among the speckle grains, while preserving the granular structure of the
pattern. Our method is versatile and allows for generating speckle patterns
with enhanced or diminished contrast in a controlled manner.


title:
Electric Field Control of Soliton Motion and Stacking in Trilayer
  Graphene

abstract:
  The crystal structure of a material plays an important role in determining
its electronic properties. Changing from one crystal structure to another
involves a phase transition which is usually controlled by a state variable
such as temperature or pressure. In the case of trilayer graphene, there are
two common stacking configurations (Bernal and rhombohedral) which exhibit very
different electronic properties. In graphene flakes with both stacking
configurations, the region between them consists of a localized strain soliton
where the carbon atoms of one graphene layer shift by the carbon-carbon bond
distance. Here we show the ability to move this strain soliton with a
perpendicular electric field and hence control the stacking configuration of
trilayer graphene with only an external voltage. Moreover, we find that the
free energy difference between the two stacking configurations scales
quadratically with electric field, and thus rhombohedral stacking is favored as
the electric field increases. This ability to control the stacking order in
graphene opens the way to novel devices which combine structural and electrical
properties.


title: Indirect Detection Signatures for the Origin of Asymmetric Dark Matter

abstract:
  We study the decay signatures of Asymmetric Dark Matter (ADM) via higher
dimension operators which are responsible for generating the primordial dark
matter (DM) asymmetry. Since the signatures are sensitive both to the nature of
the higher dimension operator generating the DM asymmetry and to the sign of
the baryon or lepton number that the DM carries, indirect detection may provide
a window into the nature of the mechanism which generates the DM asymmetry. We
consider in particular dimension-6 fermionic operators of the form ${\cal
O}_{ADM} = X {\cal O}_{B-L}/M^2$, where ${\cal O}_{B-L} = u^c d^c d^c,~\ell
\ell e^c,~q \ell d^c$ (or operators related through a Hermitian conjugate) with
the scale $M$ around or just below the GUT scale. We derive constraints on ADM
particles both in the natural mass range (around a few GeV), as well as in the
range between 100 GeV to 10 TeV. For light ADM, we focus on constraints from
both the low energy gamma ray data and proton/anti-proton fluxes. For heavy
ADM, we consider $\gamma$-rays and proton/anti-proton fluxes, and we fit
$e^+/e^-$ data from AMS-02 and H.E.S.S. (neglecting the Fermi charged particle
fluxes which disagree with AMS-02 below 100 GeV). We show that, although the
best fit regions from electron/positron measurement are still in tension with
other channels on account of the H.E.S.S. measurement at high energies,
compared to an ordinary symmetric dark matter scenario, the decay of DM with a
primordial asymmetry reduces the tension. Better measurement of the flux at
high energy will be necessary to draw a definite conclusion about the viability
of decaying DM as source for the signals.


title:
Meissner Effect Probing of Odd-Frequency Triplet Pairing in
  Superconducting Spin Valves

abstract:
  Superconducting correlations which are long-ranged in magnetic systems have
attracted much attention due to their spin-polarization properties and
potential use in spintronic devices. Whereas experiments have demonstrated the
slow decay of such correlations, it has proven more difficult to obtain a
smoking gun signature of their odd-frequency character which is responsible,
e.g. for their gapless behavior. We here demonstrate that the magnetic
susceptibility response of a normal metal in contact with a superconducting
spin-valve provides precisely this signature, namely in form of an anomalous
"positive" Meissner effect which may be tuned back to a conventional "negative"
Meissner response simply by altering the magnetization configuration of the
spin-valve.


title:
Near-Infrared long-slit spectra of Seyfert Galaxies: gas excitation
  across the central kiloparsec

abstract:
  The excitation of the gas phase of the interstellar medium can be driven by
various mechanisms. In galaxies with an active nucleus, such as Seyfert
galaxies, both radiative and mechanical energy from the central black hole, or
the stars in the disk surrounding it may play a role. We investigate the
relative importance and range of influence of the active galactic nucleus for
the excitation of ionized and molecular gas in the central kiloparsec of its
host galaxy. We present H- and K-band long-slit spectra for a sample of 21
nearby (D <70 Mpc) Seyfert galaxies obtained with the NIRSPEC instrument on the
Keck telescope. For each galaxy, we fit the nebular line emission, stellar
continua, and warm molecular gas as a function of distance from the nucleus.
Our analysis does not reveal a clear difference between the nucleus proper and
off-nuclear environment in terms of excitation mechanisms, suggesting that the
influence of an AGN reaches far into the disk of the host galaxy. The radial
variations in emission line ratios indicate that, while local mechanisms do
affect the gas excitation, they are often averaged out when measuring over
extended regions. The fully calibrated long-slit spectra, as well as our
fitting results, are made available on-line.


title: Towards an Effective Field Theory on the Light-Shell

abstract:
  We discuss our work toward the construction of a light-shell effective theory
(LSET), an effective field theory for describing the matter emerging from
high-energy collisions and the accompanying radiation. We work in the highly
simplified venue of 0-flavor scalar quantum electrodynamics, with a gauge
invariant product of scalar fields at the origin of space-time as the source of
high-energy charged particles. Working in this simple gauge theory allows us to
focus on the essential features of LSET. We describe how the effective theory
is constructed and argue that it can reproduce the full theory tree-level
amplitude. We study the 1-loop radiative corrections in the LSET and suggest
how the leading double-logs in the full theory at 1-loop order can be
reproduced by a purely angular integral in the LSET.


title:
Spectroscopic Confirmation of Young Planetary-Mass Companions on Wide
  Orbits

abstract:
  We present moderate-resolution ($R$$\sim$4000-5000) near-infrared integral
field spectroscopy of the young (1-5 Myr) 6-14 $M_\mathrm{Jup}$ companions ROXs
42B b and FW Tau b obtained with Keck/OSIRIS and Gemini-North/NIFS. The
spectrum of ROXs 42B b exhibits clear signs of low surface gravity common to
young L dwarfs, confirming its extreme youth, cool temperature, and low mass.
Overall, it closely resembles the free-floating 4-7 $M_\mathrm{Jup}$ L-type
Taurus member 2MASS J04373705+2331080. The companion to FW Tau AB is more
enigmatic. Our optical and near-infrared spectra show strong evidence of
outflow activity and disk accretion in the form of line emission from [S II],
[O I], H$\alpha$, Ca II, [Fe II], Pa$\beta$, and H$_2$. The molecular hydrogen
emission is spatially resolved as a single lobe that stretches $\approx$0.1"
(15 AU). Although the extended emission is not kinematically resolved in our
data, its morphology resembles shock-excited H$_2$ jets primarily seen in young
Class 0 and Class I sources. The near-infrared continuum of FW Tau b is mostly
flat and lacks the deep absorption features expected for a cool, late-type
object. This may be a result of accretion-induced veiling, especially in light
of its strong and sustained H$\alpha$ emission ($EW$(H$\alpha$)$\gtrsim$290
\AA). Alternatively, FW Tau b may be a slightly warmer (M5-M8) accreting
low-mass star or brown dwarf (0.03-0.15 $M_{\odot}$) with an edge-on disk.
Regardless, its young evolutionary stage is in stark contrast to its Class III
host FW Tau AB, indicating a more rapid disk clearing timescale for the host
binary system than for its wide companion. Finally, we present near-infrared
spectra of the young ($\sim$2-10 Myr) low-mass (12-15 $M_\mathrm{Jup}$)
companions GSC 6214-210 B and SR 12 C and find they best resemble low gravity
M9.5 and M9 substellar templates.


title:
A panchromatic analysis of starburst galaxy M82: Probing the dust
  properties

abstract:
  (Abridged) We combine NUV, optical and IR imaging of the nearby starburst
galaxy M82 to explore the properties of the dust both in the interstellar
medium of the galaxy and the dust entrained in the superwind. The three NUV
filters of Swift/UVOT enable us to probe in detail the properties of the
extinction curve in the region around the 2175A bump. The NUV colour-colour
diagram strongly rules out a Calzetti-type law, which can either reflect
intrinsic changes in the dust properties or in the star formation history
compared to starbursts well represented by such an attenuation law. We
emphasize that it is mainly in the NUV region where a standard Milky-Way-type
law is preferred over a Calzetti law. The age and dust distribution of the
stellar populations is consistent with the scenario of an encounter with M81 in
the recent 400 Myr. The radial gradients of the NUV and optical colours in the
superwind region support the hypothesis that the emission in the wind cone is
driven by scattering from dust grains entrained in the ejecta. The observed
wavelength dependence reveals either a grain size distribution $n(a)\propto
a^{-2.5}$, where $a$ is the size of the grain, or a flatter distribution with a
maximum size cutoff, suggesting that only small grains are entrained in the
supernovae-driven wind.


title:
Detection of white dwarf companions to blue stragglers in the open
  cluster NGC 188: direct evidence for recent mass transfer

abstract:
  Several possible formation pathways for blue straggler stars have been
developed recently, but no one pathway has yet been observationally confirmed
for a specific blue straggler. Here we report the first findings from a Hubble
Space Telescope ACS/SBC far-UV photometric program to search for white dwarf
companions to blue straggler stars. We find three hot and young white dwarf
companions to blue straggler stars in the 7-Gyr open cluster NGC 188,
indicating that mass transfer in these systems ended less than 300 Myr ago.
These companions are direct and secure observational evidence that these blue
straggler stars were formed through mass transfer in binary stars. Their
existence in a well-studied cluster environment allows for observational
constraints of both the current binary system and the progenitor binary system,
mapping the entire mass transfer history.


title: A New Look at Higgs Constraints on Stops

abstract:
  We present a simple new way to visualize the constraints of Higgs coupling
measurements on light stops in natural SUSY scenarios beyond the MSSM, which
works directly in the plane of stop mass eigenvalues (with no need to make
assumptions about mixing angles). For given stop mass eigenvalues, the smallest
value of $X_t$ that can bring the correction to the $h \to gg$ and $h\to
\gamma\gamma$ couplings into agreement with data is computed. Requiring that
this $X_t$ is consistent--i.e. that the chosen mass eigenvalues can be the
outcome of diagonalizing a matrix with a given off-diagonal term--rules out the
possibility that both stops have a mass below $\approx$ 400 GeV. Requiring that
$X_t$ is not fine-tuned for agreement with the data shows that neither stop can
be lighter than $\approx$ 100 GeV. These constraints are interesting because,
unlike direct searches, they apply no matter how stops decay, and suggest a
minimum electroweak fine-tuning of between a factor of 5 and 10. We show that a
multi-parameter fit can slightly weaken this conclusion by allowing a large
Higgs coupling to $b$-quarks, but only if a second Higgs boson is within reach
of experiment. Certain models, like $R$-symmetric models with Dirac gauginos,
are much more strongly constrained because they predict negligible $X_t$. We
illustrate how the constraints will evolve given precise measurements at future
colliders (HL-LHC, ILC, and TLEP), and comment on the more difficult case of
Folded Supersymmetry.


title:
Mid-Infrared High-Contrast Imaging of HD 114174 B : An Apparent Age
  Discrepancy in a "Sirius-Like" Binary System

abstract:
  We present new observations of the faint "Sirius-like" companion discovered
to orbit HD 114174. Previous attempts to image HD 114174 B at mid-infrared
wavelengths using NIRC2 at Keck have resulted in a non-detection. Our new
L'-band observations taken with the Large Binocular Telescope and LMIRCam
recover the companion ($\Delta L$ = 10.15 $\pm$ 0.15 mag, $\rho$ = 0.675''
$\pm$ 0.016'') with a high signal-to-noise ratio (10 $\sigma$). This
measurement represents the deepest L' high-contrast imaging detection at
sub-arcsecond separations to date, including extrasolar planets. We confirm
that HD 114174 B has near-infrared colors consistent with the interpretation of
a cool white dwarf ($J-L'$ = 0.76 $\pm$ 0.19 mag, $K-L'$ = 0.64 $\pm$ 0.20).
New model fits to the object's spectral energy distribution indicate a
temperature $T_{\rm eff}$ = 4260 $\pm$ 360 K, surface gravity log g = 7.94
$\pm$ 0.03, a cooling age t$_{c} \approx$ 7.8 Gyr, and mass $M$ = 0.54 $\pm$
0.01 $M_{\odot}$. We find that the cooling age given by theoretical atmospheric
models do not agree with the age of HD 114174 A derived from both
isochronological and gyrochronological analyses. We speculate on possible
scenarios to explain the apparent age discrepancy between the primary and
secondary. HD 114174 B is a nearby benchmark white dwarf that will ultimately
enable a dynamical mass estimate through continued Doppler and astrometric
monitoring. Efforts to characterize its physical properties in detail will test
theoretical atmospheric models and improve our understanding of white dwarf
evolution, cooling, and progenitor masses.


title: Kinematic transitions and streams in galaxy halos

abstract:
  The chemo-dynamics of galaxy halos beyond the Local Group may now be mapped
out through the use of globular clusters and planetary nebulae as bright tracer
objects, along with deep multi-slit spectroscopy of the integrated stellar
light. We present results from surveying nearby early-type galaxies, including
evidence for kinematically distinct halos that may reflect two-phase galaxy
assembly. We also demonstrate the utility of the tracer approach in measuring
the kinematics of stellar substructures around the Umbrella Galaxy, which allow
us to reconstruct the progenitor properties and stream orbit.


title:
Quantum quenches and competing orders: I. Time-dependent
  Hartree-Fock+BCS theory

abstract:
  We study the non-equlibrium dynamics of an electronic model of competing bond
density wave order and $d$-wave superconductivity. In a time-dependent
Hartree-Fock+BCS approximation, the dynamics reduces to the equations of motion
of operators realizing the generators of SU(4) at each pair of momenta,
$(\boldsymbol{k}, -\boldsymbol{k})$, in the Brillouin zone. We compare the
results of numerical studies of our model with recent picosecond optical
experiments.


title:
Star formation in high redshift galaxies including Supernova feedback:
  effect on stellar mass and luminosity functions

abstract:
  We present a semi-analytical model of high redshift galaxy formation. In our
model the star formation inside a galaxy is regulated by the feedback from
supernova (SNe) driven outflows. We derive a closed analytical form for star
formation rate in a single galaxy taking account of the SNe feedback in a
self-consistent manner. We show that our model can explain the observed
correlation between the stellar mass and the circular velocity of galaxies from
dwarf galaxies to massive galaxies of $10^{12} M_\odot$. For small mass dwarf
galaxies additional feedback other than supernova feedback is needed to explain
the spread in the observational data. Our models reproduce the observed 3-D
fundamental correlation between the stellar mass, gas phase metallicity and
star formation rate in galaxies establishing that the SNe feedback plays a
major role in building this relation. Further, the observed UV luminosity
functions of Lyman-Break galaxies (LBGs) are well explained by our feedback
induced star formation model for a vast redshift range of $1.5 \le z \le 8$. In
particular, the flattening of the luminosity functions at the low luminosity
end naturally arises due to our explicit SNe feedback treatment.


title:
Evolution in the Escape Fraction of Ionizing Photons and the Decline in
  Strong Lya Emission from z>6 Galaxies

abstract:
  The rapid decline in the number of strong Lyman Alpha (Lya) emitting galaxies
at z > 6 provides evidence for neutral hydrogen in the IGM, but is difficult to
explain with plausible models for reionization. We demonstrate that the
observed reduction in Lya flux from galaxies at z > 6 can be explained by
evolution in the escape fraction of ionizing photons, f_esc. We find that the
median observed drop in the fraction of galaxies showing strong Lya emission,
as well as the observed evolution of the Lya luminosity function both follow
from a small increase in f_esc of Delta f_esc ~ 0.1 from f_esc ~ 0.6 at z ~ 6.
This high escape fraction may be at odds with current constraints on the
ionising photon escape fraction, which favor smaller values of f_esc < 20%.
However, models that invoke a redshift evolution of f_ esc that is consistent
with these constraints can suppress the z~7 Lya flux to the observed level, if
they also include a small evolution in global neutral fraction of Delta x_HI ~
0.2. Thus, an evolving escape fraction of ionising photons can be a plausible
part of the explanation for evolution in the Lya emission of high redshift
galaxies. More generally, our analysis also shows that the drop in the Lya
fraction is quantitatively consistent with the observed evolution in the Lya
luminosity functions of Lya Emitters.


title: Spin and charge ordering in three-leg ladders in oxyborates

abstract:
  We study the spin ordering within the 3-leg ladders present in the oxyborate
Fe(3)O(2)BO(3) consisting of localized classical spins interacting with
conduction electrons (one electron per rung). We also consider the competition
with antiferromagnetic superexchange interactions to determine the magnetic
phase diagram. Beside a ferromagnetic phase we find (i) a phase with
ferromagnetic rungs ordered antiferromagnetically (ii) a zig-zag canted spin
ordering along the legs. We also determine the induced charge ordering within
the different phases and the interplay with lattice instability. Our model is
discussed in connection with the lattice dimerization transition observed in
this system, emphasizing on the role of the magnetic structure.


title:
Quantum spin liquid with a Majorana Fermi surface on the
  three-dimensional hyperoctagon lattice

abstract:
  Motivated by the recent synthesis of $\beta$-Li$_2$IrO$_3$ -- a spin-orbit
entangled $j=1/2$ Mott insulator with a three-dimensional lattice structure of
the Ir$^{4+}$ ions -- we consider generalizations of the Kitaev model believed
to capture some of the microscopic interactions between the Iridium moments on
various trivalent lattice structures in three spatial dimensions. Of particular
interest is the so-called hyperoctagon lattice -- the premedial lattice of the
hyperkagome lattice, for which the ground state is a gapless quantum spin
liquid where the gapless Majorana modes form an extended two-dimensional
Majorana Fermi surface. We demonstrate that this Majorana Fermi surface is
inherently protected by lattice symmetries and discuss possible instabilities.
We thus provide the first example of an analytically tractable microscopic
model of interacting SU(2) spin-1/2 degrees of freedom in three spatial
dimensions that harbors a spin liquid with a two-dimensional spinon Fermi
surface.


title:
Simulations of Ion Acceleration at Non-relativistic Shocks. II. Magnetic
  Field Amplification

abstract:
  We use large hybrid simulations to study ion acceleration and generation of
magnetic turbulence due to the streaming of particles that are
self-consistently accelerated at non-relativistic shocks. When acceleration is
efficient, we find that the upstream magnetic field is significantly amplified.
The total amplification factor is larger than 10 for shocks with Alfv\'enic
Mach number $M=100$, and scales with the square root of $M$. The spectral
energy density of excited magnetic turbulence is determined by the energy
distribution of accelerated particles, and for moderately-strong shocks
($M\lesssim30$) agrees well with the prediction of resonant streaming
instability, in the framework of quasilinear theory of diffusive shock
acceleration. For $M\gtrsim30$, instead, Bell's non-resonant hybrid (NRH)
instability is predicted and found to grow faster than resonant instability.
NRH modes are excited far upstream by escaping particles, and initially grow
without disrupting the current, their typical wavelengths being much shorter
than the current ions' gyroradii. Then, in the nonlinear stage, most unstable
modes migrate to larger and larger wavelengths, eventually becoming resonant in
wavelength with the driving ions, which start diffuse. Ahead of strong shocks
we distinguish two regions, separated by the free-escape boundary: the far
upstream, where field amplification is provided by the current of escaping ions
via NRH instability, and the shock precursor, where energetic particles are
effectively magnetized, and field amplification is provided by the current in
diffusing ions. The presented scalings of magnetic field amplification enable
the inclusion of self-consistent microphysics into phenomenological models of
ion acceleration at non-relativistic shocks.


title:
Azimuthal-angle dependence of charged-pion-interferometry measurements
  with respect to 2$^{\rm nd}$- and $3^{\rm rd}$-order event planes in Au$+$Au
  collisions at $\sqrt{s_{_{NN}}}=200$ GeV

abstract:
  Charged-pion-interferometry measurements were made with respect to the
2$^{\rm nd}$- and 3$^{\rm rd}$-order event plane for Au$+$Au collisions at
$\sqrt{s_{_{NN}}}=200$ GeV. A strong azimuthal-angle dependence of the
extracted Gaussian-source radii was observed with respect to both the 2$^{\rm
nd}$- and 3$^{\rm rd}$-order event planes. The results for the 2$^{\rm
nd}$-order dependence indicate that the initial eccentricity is reduced during
the medium evolution, but not reversed in the final state, which is consistent
with previous results. In contrast, the results for the 3$^{\rm rd}$-order
dependence indicate that the initial triangular shape is significantly reduced
and potentially reversed by the end of the medium evolution, and that the
3$^{\rm rd}$-order oscillations are largely dominated by the dynamical effects
from triangular flow.


title: Modeling Quantum Gravity Effects in Inflation

abstract:
  Cosmological models in 1+1 dimensions are an ideal setting for investigating
the quantum structure of inflationary dynamics -- gravity is renormalizable,
while there is room for spatial structure not present in the minisuperspace
approximation. We use this fortuitous convergence to investigate the mechanism
of slow-roll eternal inflation. A variant of 1+1 Liouville gravity coupled to
matter is shown to model precisely the scalar sector of cosmological
perturbations in 3+1 dimensions. A particular example of quintessence in 1+1d
is argued on the one hand to exhibit slow-roll eternal inflation according to
standard criteria; on the other hand, a field redefinition relates the model to
pure de Sitter gravity coupled to a free scalar matter field with no potential.
This and other examples show that the standard logic leading to slow-roll
eternal inflation is not invariant under field redefinitions, thus raising
concerns regarding its validity. Aspects of the quantization of Liouville
gravity as a model of quantum de Sitter space are also discussed.


title:
Summing over trajectories of stochastic dynamics with multiplicative
  noise

abstract:
  We demonstrate that the conventional path integral formulations generate
inconsistent results exemplified by the geometric Brownian motion under the
general stochastic interpretation. We thus develop a novel path integral
formulation for the overdamped Langevin equation with the multiplicative noise.
The present path integral leads to the corresponding Fokker-Planck equation,
and naturally gives a normalized transition probability consistently in
examples for general stochastic interpretations. Our result can be applied to
study the fluctuation theorems and numerical calculations based on the path
integral framework.


title: Arc-quasianalytic functions

abstract:
  We work with quasianalytic classes of functions. Consider a real-valued
function y = f(x) on an open subset U of Euclidean space, which satisfies a
quasianalytic equation G(x, y) = 0. We prove that f is arc-quasianalytic (i.e.,
its restriction to every quasianalytic arc is quasianalytic) if and only if f
becomes quasianalytic after (a locally finite covering of U by) finite
sequences of local blowing-ups. This generalizes a theorem of the first two
authors on arc-analytic functions.


title:
Edge spin accumulation in 2D electron and hole systems in a
  quasi-ballistic regime

abstract:
  We consider a two-dimensional structure with spin-orbit-related splitting of
the electron (hole) spectrum and calculate the edge spin density which appears
due to the intrinsic mechanism of spin-orbit interaction in the presence of a
charge current through the structure. We concentrate on the quasi-ballistic
case when a mean free path, being much smaller than the sample size, is larger
than the spin precession length determined by the value of the spin-orbit
splitting. We show that regardless of the presence or absence of the bulk spin
current the main source of the edge spin density is the boundary scattering
itself. The character of the edge spin density depends on the smoothness of the
bulk impurity potential. We have calculated the edge spin density profile for
an arbitrary smoothness of the scattering potential in the bulk, and discussed
relation to the existing experiments for two-dimensional holes.


title:
Observation of the $\beta$-delayed $\gamma$-proton decay of $^{56}$Zn
  and its impact on the Gamow Teller strength evaluation

abstract:
  We report the observation of a very exotic decay mode at the proton
drip-line, the $\beta$-delayed $\gamma$-proton decay, clearly seen in the
$\beta$ decay of the $T_z$ = -2 nucleus $^{56}$Zn. Three $\gamma$-proton
sequences have been observed after the $\beta$ decay. Here this decay mode,
already observed in the $sd$-shell, is seen for the first time in the
$fp$-shell. Both $\gamma$ and proton decays have been taken into account in the
estimation of the Fermi (F) and Gamow Teller (GT) strengths. Evidence for
fragmentation of the Fermi strength due to strong isospin mixing is found.


title:
A Millennium Bug Still Bites Public Health - An Illustration Using
  Cancer Mortality

abstract:
  Accurate estimation of cancer mortality rates and the comparison across
cancer sites, populations or time periods is crucial to public health, as
identification of vulnerable groups who suffer the most from these diseases may
lead to efficient cancer care and control with timely treatment. Because cancer
mortality rate varies with age, comparisons require age-standardization using a
reference population. The current method of using the Year 2000 Population
Standard is standard practice, but serious concerns have been raised about its
lack of justification. We have found that using the US Year 2000 Population
Standard as reference overestimates prostate cancer mortality rates by 12-91%
during the period 1970-2009 across all six sampled U.S. states, and also
underestimates case fatality rates by 9-78% across six cancer sites, including
female breast, cervix, prostate, lung, leukemia and colon-rectum. We develop a
mean reference population method to minimize the bias using mathematical
optimization theory and statistical modeling. The method corrects the bias to
the largest extent in terms of squared loss and can be applied broadly to
studies of many diseases.


title:
Constant mean curvature spacelike hypersurfaces in Lorentzian warped
  products and Calabi-Bernstein type problems

abstract:
  In this paper we provide several uniqueness and non-existence results for
complete parabolic constant mean curvature spacelike hypersurfaces in
Lorentzian warped products under appropriate geometric assumptions. As a
consequence of this parametric study, we obtain very general uniqueness and
non-existence results for a large family of uniformly elliptic EDP's, so
solving the Calabi-Bernstein problem in a wide family of spacetimes.


title:
Fitting of interatomic potentials without forces: a parallel particle
  swarm optimization algorithm

abstract:
  We present a methodology for fitting interatomic potentials to ab initio
data, using the particle swarm optimization (PSO) algorithm, needing only a set
of positions and energies as input. The prediction error of energies associated
with the fitted parameters can be close to 1 meV/atom or lower, for reference
energies having a standard deviation of about 0.5 eV/atom. We tested our method
by fitting a Sutton-Chen potential for copper from \emph{ab initio} data, which
is able to recover structural and dynamical properties, and obtain a better
agreement of the predicted melting point versus the experimental value, as
compared to the prediction of the standard Sutton-Chen parameters.


title: Electrostatic theory of metal whiskers

abstract:
  Needle shaped whiskers grow on various metal surfaces often across leads of a
package causing current leakage or short circuits and raising reliability
issues in electronic components. The nature of metal whiskers remains a mystery
after several decades of research. Here, the existence of metal whiskers is
attributed to the energy gain due to electrostatic polarization of needle
shaped metal filaments in the electric field. The field is induced by surface
imperfections: contaminations, oxide states, grain boundaries, etc. A proposed
theory provides closed form expressions and quantitative estimates for the
whisker nucleation and growth rates, explains the range of whisker parameters
and effects of external biasing, and predicts statistical distribution of their
lengths.


title: OPE Methods for the Holomorphic Higgs Portal

abstract:
  We develop a systematic and general approach to study the effective Higgs
Lagrangian in a supersymmetric framework in which the Higgs fields in the
visible sector couple weakly to another sector. The extra sector may be
strongly coupled in general. It is assumed to be superconformal in the
ultraviolet, but develop a mass-gap with supersymmetry breaking in the
infrared. The main technique used in our approach is that of the operator
product expansion (OPE). By using OPE methods we are able to compute the
parameters in the Higgs Lagrangian to quadratic order and make general
statements that are applicable to many classes of models. Not only does this
approach allow us to understand the traditional problems plaguing simple models
from a different perspective, it also reveals new possibilities for solutions
of these problems. The methods and results of our work should be useful in
constructing a viable and natural model of physics beyond the Standard Model.


title: The RTT-Realization for the Deformed gl(2|2) Yangian

abstract:
  In this paper we work out the RTT-realization for the Yangian algebra of the
Hubbard model and AdS/CFT correspondence. We find that this Yangian algebra is
of a non-standard type in which the levels of the Yangian mix. The crucial
feature that allows this is a braiding factor that deforms the coproduct and
generates the central extensions of the underlying sl(2|2) Lie algebra. In our
RTT-realization we have also been able to incorporate the so-called secret
symmetry and we were able to extend it to higher Yangian levels. Finally, we
discuss the center of the Yangian and the automorphisms related to crossing
symmetry.


title: Minimal area submanifolds in AdS x compact

abstract:
  We describe the asymptotic behavior of minimal area submanifolds in product
spacetimes of an asymptotically hyperbolic space times a compact internal
manifold. In particular, we find that unlike the case of a minimal area
submanifold just in an asymptotically hyperbolic space, the internal part of
the boundary submanifold is constrained to be itself a minimal area
submanifold. For applications to holography, this tells us what are the allowed
"flavor branes" that can be added to a holographic field theory. We also give a
compact geometric expression for the spectrum of operator dimensions associated
with the slipping modes of the submanifold in the internal space. We illustrate
our results with several examples, including some that haven't appeared in the
literature before.


title:
Josephson physics of spin-orbit coupled elongated Bose-Einstein
  condensates

abstract:
  We consider an ultracold bosonic binary mixture confined in a one-dimensional
double-well trap. The two bosonic components are assumed to be two hyperfine
internal states of the same atom. We suppose that these two components are
spin-orbit coupled between each other. We employ the two-mode approximation
starting from two coupled Gross-Pitaevskii equations and derive a system of
ordinary differential equations governing the temporal evolution of the
inter-well population imbalance of each component and that between the two
bosonic species. We study the Josephson oscillations of these spin-orbit
coupled Bose-Einstein condensates by analyzing the interplay between the
interatomic interactions and the spin-orbit coupling and the self-trapped
dynamics of the inter-species imbalance. We show that the dynamics of this
latter variable is crucially determined by the relationship between the
spin-orbit coupling, the tunneling energy, and the interactions.


title: Experience Implementing a Performant Category-Theory Library in Coq

abstract:
  We describe our experience implementing a broad category-theory library in
Coq. Category theory and computational performance are not usually mentioned in
the same breath, but we have needed substantial engineering effort to teach Coq
to cope with large categorical constructions without slowing proof script
processing unacceptably. In this paper, we share the lessons we have learned
about how to represent very abstract mathematical objects and arguments in Coq
and how future proof assistants might be designed to better support such
reasoning. One particular encoding trick to which we draw attention allows
category-theoretic arguments involving duality to be internalized in Coq's
logic with definitional equality. Ours may be the largest Coq development to
date that uses the relatively new Coq version developed by homotopy type
theorists, and we reflect on which new features were especially helpful.


title:
Modeling AGN Feedback in Cool-Core Clusters: The Balance between Heating
  and Cooling

abstract:
  We study the long-term evolution of an idealized cool-core galaxy cluster
under the influence of momentum-driven AGN feedback using three-dimensional
high-resolution (60 pc) adaptive mesh refinement (AMR) simulations. The
momentum-driven AGN feedback is modeled with a pair of (small-angle) precessing
jets, and the jet power is calculated based on the accretion rate of the cold
gas in the vicinity of the Supermassive Black Hole (SMBH). The ICM first cools
into clumps along the propagation direction of the AGN jets. As the jet power
increases, gas condensation occurs isotropically, forming spatially extended
(up to a few tens kpc) structures that resemble the observed $\rm H\alpha$
filaments in Perseus and many other cool-core cluster. Jet heating elevates the
gas entropy and cooling time, halting clump formation. The cold gas that is not
accreted onto the SMBH settles into a rotating disk of $\sim 10^{11}$
M$_{\odot}$. The hot gas cools directly onto the cold disk while the SMBH
accretes from the innermost region of the disk, powering the AGN that maintains
a thermally balanced steady state for a few Gyr. The mass cooling rate averaged
over 7 Gyr is $\sim 30$ M$_{\odot}$/yr, an order of magnitude lower than the
classic cooling flow value (which we obtain in runs without the AGN). Medium
resolution simulations produce similar results, but when the resolution is
lower than 0.5 kpc, the cluster experiences cycles of gas condensation and AGN
outbursts. Owing to its self-regulating mechanism, AGN feedback can
successfully balance cooling with a wide range of model parameters. Besides
suppressing cooling, our model produces cold structures in early stages (up to
$\sim 2$ Gyr) that are in good agreement with the observations. However, the
long-lived massive cold disk is unrealistic, suggesting that additional
physical processes are still needed.


title: Chinese Remainder Theorem for Cyclotomic Polynomials in $\mathbf{Z}[X]$

abstract:
  By the Chinese remainder theorem, the canonical map \[\Psi_n: R[X]/(X^n-1)\to
\oplus_{d|n} R[X]/\Phi_d(X)\] is an isomorphism when $R$ is a field whose
characteristic does not divide $n$ and $\Phi_d$ is the $d$th cyclotomic
polynomial. When $R$ is the ring $\mathbf{Z}$ of rational integers, this map is
injective but not surjective. In this paper, we give an explicit formula for
the elementary divisors of the cokernel of $\Psi_n$(when $R=\mathbb{Z}$) using
the prime factorisation of $n$. We also give a pictorial algorithm using Young
Tableaux that takes $O(n^{3+\epsilon})$ bit operations for any $\epsilon > 0$
to determine a basis of Smith vectors (see Definition 3.1) for the codomain of
$\Psi_n$. In general when $R$ is an integral domain, we prove that the
determinant of $\Psi : R[X]/(\prod_j f_j) \to \bigoplus_j R[X]/(f_j)$ written
with respect to the standard basis is $\prod_{1 \leqslant i < j
  \leqslant n} \mathcal{R}(f_j, f_i)$, where $f_i$'s are pairwise relatively
prime monic polynomials and $\mathcal{R}(f_j, f_i)$ is the resultant of $f_j$
and $f_i$.


title:
A narrow-band unfitted finite element method for elliptic PDEs posed on
  surfaces

abstract:
  The paper studies a method for solving elliptic partial differential
equations posed on hypersurfaces in $\mathbb{R}^N$, $N=2,3$. The method allows
a surface to be given implicitly as a zero level of a level set function. A
surface equation is extended to a narrow-band neighborhood of the surface. The
resulting extended equation is a non-degenerate PDE and it is solved on a bulk
mesh that is unaligned to the surface. An unfitted finite element method is
used to discretize extended equations. Error estimates are proved for finite
element solutions in the bulk domain and restricted to the surface. The
analysis admits finite elements of a higher order and gives sufficient
conditions for archiving the optimal convergence order in the energy norm.
Several numerical examples illustrate the properties of the method.


title:
A hierarchy of noncanonical Hamiltonian systems: circulation laws in an
  extended phase space

abstract:
  The dynamics of an ideal fluid or plasma is constrained by topological
invariants such as the circulation of (canonical) momentum or, equivalently,
the flux of the vorticity or magnetic fields. In the Hamiltonian formalism,
topological invariants restrict the orbits to submanifolds of the phase space.
While the coadjoint orbits have a natural symplectic structure, the global
geometry of the degenerate (constrained) Poisson manifold can be very complex.
Some invariants are represented by the center of the Poisson algebra (i.e., the
Casimir elements such as the helicities), and then, the global structure of
phase space is delineated by Casimir leaves. However, a general constraint is
not necessarily integrable, which precludes the existence of an appropriate
Casimir element; the circulation is an example of such an invariant. In this
work, we formulate a systematic method to embed a Hamiltonian system in an
extended phase space; we introduce mock fields and extend the Poisson algebra
so that the mock fields are Lie-dragged by the flow vector. A mock field
defines a new Casimir element, a cross helicity, which represents topological
constraints including the circulation. Unearthing a Casimir element brings
about immense advantage in the study of dynamics and equilibria -- the
so-called energy-Casimir method becomes ready available. Yet, a mock field does
not a priori have a physical meaning. Here we proffer an interpretation of a
Casimir element obtained, e.g., by such a construction as an adiabatic
invariant associated with a hidden "microscopic" angle variable, and in this
way give the mock field a physical meaning. We proceed further and consider a
perturbation of the Hamiltonian by a canonical pair, composed of the Casimir
element and the angle, that causes the topological constraint to be unfrozen.
The theory is applied to the tearing modes of MHD.

categories: math-ph math.DG math.DS math.MP physics.flu-dyn physics.plasm-ph


title:
Overcoming loss of contrast in atom interferometry due to gravity
  gradients

abstract:
  Long-time atom interferometry is instrumental to various high-precision
measurements of fundamental physical properties, including tests of the
equivalence principle. Due to rotations and gravity gradients, the classical
trajectories characterizing the motion of the wave packets for the two branches
of the interferometer do not close in phase space, an effect which increases
significantly with the interferometer time. The relative displacement between
the interfering wave packets in such open interferometers leads to a fringe
pattern in the density profile at each exit port and a loss of contrast in the
oscillations of the integrated particle number as a function of the phase
shift. Paying particular attention to gravity gradients, we present a simple
mitigation strategy involving small changes in the timing of the laser pulses
which is very easy to implement. A useful representation-free description of
the state evolution in an atom interferometer is introduced and employed to
analyze the loss of contrast and mitigation strategy in the general case. (As a
by-product, a remarkably compact derivation of the phase-shift in a general
light-pulse atom interferometer is provided.) Furthermore, exact results are
obtained for (pure and mixed) Gaussian states which allow a simple
interpretation in terms of the alignment of Wigner functions in phase-space.
Analytical results are also obtained for expanding Bose-Einstein condensates
within the time-dependent Thomas-Fermi approximation. Finally, a combined
strategy for rotations and nonaligned gravity gradients is considered as well.


title: Random assignment with multi-unit demands

abstract:
  We consider the multi-unit random assignment problem in which agents express
preferences over objects and objects are allocated to agents randomly based on
the preferences. The most well-established preference relation to compare
random allocations of objects is stochastic dominance (SD) which also leads to
corresponding notions of envy-freeness, efficiency, and weak strategyproofness.
We show that there exists no rule that is anonymous, neutral, efficient and
weak strategyproof. For single-unit random assignment, we show that there
exists no rule that is anonymous, neutral, efficient and weak
group-strategyproof. We then study a generalization of the PS (probabilistic
serial) rule called multi-unit-eating PS and prove that multi-unit-eating PS
satisfies envy-freeness, weak strategyproofness, and unanimity.


title: The Type Ia supernovae rate with Subaru/XMM-Newton Deep Survey

abstract:
  We present measurements of the rates of high-redshift Type Ia supernovae
derived from the Subaru/XMM-Newton Deep Survey (SXDS). We carried out repeat
deep imaging observations with Suprime-Cam on the Subaru Telescope, and
detected 1040 variable objects over 0.918 deg$^2$ in the Subaru/XMM-Newton Deep
Field. From the imaging observations, light curves in the observed $i'$-band
are constructed for all objects, and we fit the observed light curves with
template light curves. Out of the 1040 variable objects detected by the SXDS,
39 objects over the redshift range $0.2 < z < 1.4$ are classified as Type Ia
supernovae using the light curves. These are among the most distant SN Ia rate
measurements to date. We find that the Type Ia supernova rate increase up to $z
\sim 0.8$ and may then flatten at higher redshift. The rates can be fitted by a
simple power law, $r_V(z)=r_0(1+z)^\alpha$ with
$r_0=0.20^{+0.52}_{-0.16}$(stat.)$^{+0.26}_{-0.07}$(syst.)$\times 10^{-4} {\rm
yr}^{-1}{\rm Mpc}^{-3}$, and
$\alpha=2.04^{+1.84}_{-1.96}$(stat.)$^{+2.11}_{-0.86}$(syst.).


title: A Spectral Framework for Anomalous Subgraph Detection

abstract:
  A wide variety of application domains are concerned with data consisting of
entities and their relationships or connections, formally represented as
graphs. Within these diverse application areas, a common problem of interest is
the detection of a subset of entities whose connectivity is anomalous with
respect to the rest of the data. While the detection of such anomalous
subgraphs has received a substantial amount of attention, no
application-agnostic framework exists for analysis of signal detectability in
graph-based data. In this paper, we describe a framework that enables such
analysis using the principal eigenspace of a graph's residuals matrix, commonly
called the modularity matrix in community detection. Leveraging this analytical
tool, we show that the framework has a natural power metric in the spectral
norm of the anomalous subgraph's adjacency matrix (signal power) and of the
background graph's residuals matrix (noise power). We propose several
algorithms based on spectral properties of the residuals matrix, with more
computationally expensive techniques providing greater detection power.
Detection and identification performance are presented for a number of signal
and noise models, including clusters and bipartite foregrounds embedded into
simple random backgrounds as well as graphs with community structure and
realistic degree distributions. The trends observed verify intuition gleaned
from other signal processing areas, such as greater detection power when the
signal is embedded within a less active portion of the background. We
demonstrate the utility of the proposed techniques in detecting small, highly
anomalous subgraphs in real graphs derived from Internet traffic and product
co-purchases.


title: Magnetic Polarizability of Diquarks in Baryons

abstract:
  We study the response of diquark wave function in \Lambda-type baryons to
strong magnetic fields. It is found that quantum state of J=0 diquark (ud) in
the magnetic field changes due to magnetic polarizability, and constituent
quarks in (ud) diquark become polarized. The phenomenon influences polarized
quark distribution functions \Delta u(x) and \Delta d(x), which therefore may
be sensitive to the internal electromagnetic fields in hypernuclei. We also
speculate, that strange quark polarization in nucleon may originate from the
interaction of virtual (ss') quark pairs with the intrinsic magnetic field of
nucleon B $\approx$ 10^13 T.


title:
The Marchenko representation of reflectionless Jacobi and Schrodinger
  operators

abstract:
  We consider Jacobi matrices and Schrodinger operators that are reflectionless
on an interval. We give a systematic development of a certain parametrization
of this class, in terms of suitable spectral data, that is due to Marchenko.
Then some applications of these ideas are discussed.


title:
Elastic properties of eta carbide (eta-Fe2C) from ab initio
  calculations. Application to cryogenically treated gear steel

abstract:
  The elastic properties of eta-Fe2C (eta carbide) have been determined from ab
initio density functional theory (DFT) calculations using the generalized
gradient approximation (GGA). The isotropic polycrystalline elastic modulus of
eta-Fe2C has been calculated as the average of anisotropic single-crystal
elastic constants determined from the ab initio simulations. The calculated
polycrystalline elastic modulus was used to compute the elastic modulus of a
case carburised gear steel subjected to shallow cryogenic treatment (SCT) and
deep cryogenic treatment (DCT). This value was then compared with experimental
values obtained from nanoindentation. The results confirmed that the changes in
elastic modulus observed in the DCT steel can be attributed to the
precipitation of eta-Fe2C. No changes in hardness have been observed between
the SCT steel and the DCT steel. These data were then used to assess the
surface contact fatigue behaviour of the SCT and DCT steels tested under
elastohydrodynamic lubrication (EHL) conditions.


title:
High Energy X-Ray Detection OF G359.89-0.08 (Sgr A-E): Magnetic Flux
  Tube Emission Powered By Cosmic Rays?

abstract:
  We report the first detection of high-energy X-ray (E>10 keV) emission from
the Galactic Center non-thermal filament G359.89-0.08 (Sgr A-E) using data
acquired with the Nuclear Spectroscopic Telescope Array (NuSTAR). The bright
filament was detected up to ~50 keV during a NuSTAR Galactic Center monitoring
campaign. The featureless power-law spectrum with a photon index of ~2.3
confirms a non-thermal emission mechanism. The observed flux in the 3-79 keV
band is ~ 2.0e-12 erg/cm^2/s, corresponding to an unabsorbed X-ray luminosity
of ~2.6e34 erg/s assuming a distance of 8.0 kpc. Based on theoretical
predictions and observations, we conclude that Sgr A-E is unlikely to be a
pulsar wind nebula (PWN) or supernova remnant-molecular cloud (SNR-MC)
interaction, as previously hypothesized. Instead, the emission could be due to
a magnetic flux tube which traps TeV electrons. We propose two possible TeV
electron sources: old PWNe (up to ~100 kyr) with low surface brightness and
radii up to ~30 pc or molecular clouds (MCs) illuminated by cosmic rays (CRs)
from CR accelerators such as SNRs or Sgr A*.


title:
Integral identity and measure estimates for stationary Fokker-Planck
  equations

abstract:
  We consider a Fokker-Planck equation in a general domain in ${\mathbb{R}}^n$
with $L^p_{\mathrm{loc}}$ drift term and $W^{1,p}_{\mathrm{loc}}$ diffusion
term for any $p>n$. By deriving an integral identity, we give several measure
estimates of regular stationary measures in an exterior domain with respect to
diffusion and Lyapunov-like or anti-Lyapunov-like functions. These estimates
will be useful to problems such as the existence and nonexistence of stationary
measures in a general domain as well as the concentration and limit behaviors
of stationary measures as diffusion vanishes.


title:
On the non-amenability of the reflective quotient \Rmnum{1}: The
  rational case

abstract:
  Let O(f,Z) be the integral orthogonal group of an integral quadratic form f
of signature (n,1). Let R(f,Z) be the subgroup of O(f,Z) generated by all
hyperbolic reflections. Vinberg proved that if n > 29 then the reflective
quotient O(f,Z)/R(f,Z) is infinite. In this note we generalize Vinberg's
theorem and prove that if n > 91 then O(f,Z)/R(f,Z) contains a non-abelian free
group (and thus it is not amenable).


title: Joint Inference of Multiple Label Types in Large Networks

abstract:
  We tackle the problem of inferring node labels in a partially labeled graph
where each node in the graph has multiple label types and each label type has a
large number of possible labels. Our primary example, and the focus of this
paper, is the joint inference of label types such as hometown, current city,
and employers, for users connected by a social network. Standard label
propagation fails to consider the properties of the label types and the
interactions between them. Our proposed method, called EdgeExplain, explicitly
models these, while still enabling scalable inference under a distributed
message-passing architecture. On a billion-node subset of the Facebook social
network, EdgeExplain significantly outperforms label propagation for several
label types, with lifts of up to 120% for recall@1 and 60% for recall@3.


title:
Modified Anti-de-Sitter Metric, Light-Front Quantized QCD, and Conformal
  Quantum Mechanics

abstract:
  We briefly review the remarkable connections between light-front QCD, gravity
in AdS space, and conformal quantum mechanics. We discuss, in particular, the
group theoretical and geometrical aspects of the underlying one-dimensional
quantum field theory. The resulting effective theory leads to a
phenomenologically successful confining interaction potential in the
relativistic light-front wave equation which incorporates relevant
non-perturbative dynamical aspects of hadron physics.


title:
GERLUMPH Data Release 1: High-resolution cosmological microlensing
  magnification maps and eResearch tools

abstract:
  As synoptic all-sky surveys begin to discover new multiply lensed quasars,
the flow of data will enable statistical cosmological microlensing studies of
sufficient size to constrain quasar accretion disc and supermassive black hole
properties. In preparation for this new era, we are undertaking the
GPU-Enabled, High Resolution cosmological MicroLensing parameter survey
(GERLUMPH). We present here the GERLUMPH Data Release 1, which consists of
12342 high resolution cosmological microlensing magnification maps and provides
the first uniform coverage of the convergence, shear and smooth matter fraction
parameter space. We use these maps to perform a comprehensive numerical
investigation of the mass-sheet degeneracy, finding excellent agreement with
its predictions. We study the effect of smooth matter on microlensing induced
magnification fluctuations. In particular, in the minima and saddle-point
regions, fluctuations are enhanced only along the critical line, while in the
maxima region they are always enhanced for high smooth matter fractions (~0.9).
We describe our approach to data management, including the use of an SQL
database with a Web interface for data access and online analysis, obviating
the need for individuals to download large volumes of data. In combination with
existing observational databases and online applications, the GERLUMPH archive
represents a fundamental component of a new microlensing eResearch cloud. Our
maps and tools are publicly available at http://gerlumph.swin.edu.au/.


title: Multiscale Simulation of Entangled Polymer Melt with Elastic Deformation

abstract:
  To predict flow behavior of entangled polymer melt, we have developed
multiscale simulation composed of Lagrangian fluid particle simulation and
coarse-grained polymer dynamics simulation. We have introduced a particle
deformation in the Lagrangian fluid particle simulation to describe elongation
flow at a local point. The particle deformation is obtained to be consistent
with the local polymer deformation.


title: A Generalized Probabilistic Framework for Compact Codebook Creation

abstract:
  Compact and discriminative visual codebooks are preferred in many visual
recognition tasks. In the literature, a number of works have taken the approach
of hierarchically merging visual words of an initial large-sized codebook, but
implemented this approach with different merging criteria. In this work, we
propose a single probabilistic framework to unify these merging criteria, by
identifying two key factors: the function used to model class-conditional
distribution and the method used to estimate the distribution parameters. More
importantly, by adopting new distribution functions and/or parameter estimation
methods, our framework can readily produce a spectrum of novel merging
criteria. Three of them are specifically focused in this work. In the first
criterion, we adopt the multinomial distribution with Bayesian method; In the
second criterion, we integrate Gaussian distribution with maximum likelihood
parameter estimation. In the third criterion, which shows the best merging
performance, we propose a max-margin-based parameter estimation method and
apply it with multinomial distribution. Extensive experimental study is
conducted to systematically analyse the performance of the above three criteria
and compare them with existing ones. As demonstrated, the best criterion
obtained in our framework achieves the overall best merging performance among
the comparable merging criteria developed in the literature.


title: Powers of Tensors and Fast Matrix Multiplication

abstract:
  This paper presents a method to analyze the powers of a given trilinear form
(a special kind of algebraic constructions also called a tensor) and obtain
upper bounds on the asymptotic complexity of matrix multiplication. Compared
with existing approaches, this method is based on convex optimization, and thus
has polynomial-time complexity. As an application, we use this method to study
powers of the construction given by Coppersmith and Winograd [Journal of
Symbolic Computation, 1990] and obtain the upper bound $\omega<2.3728639$ on
the exponent of square matrix multiplication, which slightly improves the best
known upper bound.


title: Video Compressive Sensing for Dynamic MRI

abstract:
  We present a video compressive sensing framework, termed kt-CSLDS, to
accelerate the image acquisition process of dynamic magnetic resonance imaging
(MRI). We are inspired by a state-of-the-art model for video compressive
sensing that utilizes a linear dynamical system (LDS) to model the motion
manifold. Given compressive measurements, the state sequence of an LDS can be
first estimated using system identification techniques. We then reconstruct the
observation matrix using a joint structured sparsity assumption. In particular,
we minimize an objective function with a mixture of wavelet sparsity and joint
sparsity within the observation matrix. We derive an efficient convex
optimization algorithm through alternating direction method of multipliers
(ADMM), and provide a theoretical guarantee for global convergence. We
demonstrate the performance of our approach for video compressive sensing, in
terms of reconstruction accuracy. We also investigate the impact of various
sampling strategies. We apply this framework to accelerate the acquisition
process of dynamic MRI and show it achieves the best reconstruction accuracy
with the least computational time compared with existing algorithms in the
literature.


title:
redMaPPer III: A Detailed Comparison of the Planck 2013 and SDSS DR8
  RedMaPPer Cluster Catalogs

abstract:
  We compare the Planck Sunyaev-Zeldovich (SZ) cluster sample (PSZ1) to the
Sloan Digital Sky Survey (SDSS) redMaPPer catalog, finding that all Planck
clusters within the redMaPPer mask and within the redshift range probed by
redMaPPer are contained in the redMaPPer cluster catalog. These common clusters
define a tight scaling relation in the richness-SZ mass ($\lambda$--$M_{SZ}$)
plane, with an intrinsic scatter in richness of $\sigma_{\lambda|M_{SZ}} =
0.266 \pm 0.017$. The corresponding intrinsic scatter in true cluster halo mass
at fixed richness is $\approx 21\%$. The regularity of this scaling relation is
used to identify failures in both the redMaPPer and Planck cluster catalogs. Of
the 245 galaxy clusters in common, we identify three failures in redMaPPer and
36 failures in the PSZ1. Of these, at least 12 are due to clusters whose
optical counterpart was correctly identified in the PSZ1, but where the quoted
redshift for the optical counterpart in the external data base used in the PSZ1
was incorrect. The failure rates for redMaPPer and the PSZ1 are $1.2\%$ and
$14.7\%$ respectively, or 9.8% in the PSZ1 after subtracting the external data
base errors. We have further identified 5 PSZ1 sources that suffer from
projection effects (multiple rich systems along the line-of-sight of the SZ
detection) and 17 new high redshift ($z\gtrsim 0.6$) cluster candidates of
varying degrees of confidence. Should all of the high-redshift cluster
candidates identified here be confirmed, we will have tripled the number of
high redshift Planck clusters in the SDSS region. Our results highlight the
power of multi-wavelength observations to identify and characterize systematic
errors in galaxy cluster data sets, and clearly establish photometric data both
as a robust cluster finding method, and as an important part of defining clean
galaxy cluster samples.


title:
Predictive Green Wireless Access: Exploiting Mobility and Application
  Information

abstract:
  The ever increasing mobile data traffic and dense deployment of wireless
networks have made energy efficient radio access imperative. As networks are
designed to satisfy peak user demands, radio access energy can be reduced in a
number of ways at times of lower demand. This includes putting base stations
(BSs) to intermittent short sleep modes during low load, as well as adaptively
powering down select BSs completely where demand is low for prolonged time
periods. In order to fully exploit such energy conserving mechanisms, networks
should be aware of the user temporal and spatial traffic demands. To this end,
this article investigates the potential of utilizing predictions of user
location and application information as a means to energy saving. We discuss
the development of a predictive green wireless access (PreGWA) framework and
identify its key functional entities and their interaction. To demonstrate the
potential energy savings we then provide a case study on stored video streaming
and illustrate how exploiting predictions can minimize BS resource consumption
within a single cell, and across a network of cells. Finally, to emphasize the
practical potential of PreGWA, we present a distributed heuristic that reduces
resource consumption significantly without requiring considerable information
or signaling overhead.


title:
A framework of Rogers-Ramanujan identities and their arithmetic
  properties

abstract:
  The two Rogers-Ramanujan $q$-series \[
\sum_{n=0}^{\infty}\frac{q^{n(n+\sigma)}}{(1-q)\cdots (1-q^n)}, \] where
$\sigma=0,1$, play many roles in mathematics and physics. By the
Rogers-Ramanujan identities, they are essentially modular functions. Their
quotient, the Rogers-Ramanujan continued fraction, has the special property
that its singular values are algebraic integral units. We find a framework
which extends the Rogers-Ramanujan identities to doubly-infinite families of
$q$-series identities. If $a\in\{1,2\}$ and $m,n\geq 1$, then we have \[
\sum_{\substack{\lambda \lambda_1\leq m}} q^{a|\lambda|}
P_{2\lambda}(1,q,q^2,\dots;q^n) =\textrm{"infinite product modular function"},
\] where the $P_{\lambda}(x_1,x_2,\dots;q)$ are Hall-Littlewood polynomials.
These $q$-series are specialized characters of affine Kac--Moody algebras.
Generalizing the Rogers-Ramanujan continued fraction, we prove in the case of
$\textrm{A}_{2n}^{(2)}$ that the relevant $q$-series quotients are integral
units.


title: Frattini Argument for Hall subgroups

abstract:
  In the paper, it is proved that if a finite group $G$ possesses a $\pi$-Hall
subgroup for a set $\pi$ of primes, then every normal subgroup $A$ of $G$
possesses a $\pi$-Hall subgroup $H$ such that ${G=AN_G(H)}$.


title: Large cities are less green

abstract:
  We study how urban quality evolves as a result of carbon dioxide emissions as
urban agglomerations grow. We employ a bottom-up approach combining two
unprecedented microscopic data on population and carbon dioxide emissions in
the continental US. We first aggregate settlements that are close to each other
into cities using the City Clustering Algorithm (CCA) defining cities beyond
the administrative boundaries. Then, we use data on $\rm{CO}_2$ emissions at a
fine geographic scale to determine the total emissions of each city. We find a
superlinear scaling behavior, expressed by a power-law, between $\rm{CO}_2$
emissions and city population with average allometric exponent $\beta = 1.46$
across all cities in the US. This result suggests that the high productivity of
large cities is done at the expense of a proportionally larger amount of
emissions compared to small cities. Furthermore, our results are substantially
different from those obtained by the standard administrative definition of
cities, i.e. Metropolitan Statistical Area (MSA). Specifically, MSAs display
isometric scaling emissions and we argue that this discrepancy is due to the
overestimation of MSA areas. The results suggest that allometric studies based
on administrative boundaries to define cities may suffer from endogeneity bias.


title:
A Gapless MoS$_2$ Allotrope Possessing Both Massless Dirac and Heavy
  Fermions

abstract:
  MoS$_2$, a member of transition metal dichalcogenides (TMDs), recently
emerged as one of the fastest growing two-dimensional materials due to its
fascinating mechanical, thermal, electronic and optical properties. Unlike
graphene which possesses massless Dirac fermions with ultra-high electron
mobility, monolayer MoS$_2$ is a direct band gap semiconductor. An interesting
question arises: Can monolayer MoS$_2$ also possess massless Dirac fermions
with ultra-high electron mobility? Here, using first-principles calculations,
we show that a monolayer MoS$_2$ allotrope, which consists of repeated
square-octagon rings (abbreviated as so-MoS$_2$ to distinguish from the normal
hexagonal lattice, h-MoS$_2$) possesses both massless Dirac fermions and heavy
fermions. Distinct from the $p$-orbital Dirac fermions of graphene, the Dirac
fermions of so-MoS$_2$ are $d$-electrons and possess Fermi velocity comparable
to that of graphene. The Dirac cone structure in so-MoS$_2$ demonstrated here
greatly enriches our understanding on the physical properties of TMDs and opens
up new possibilities for developing novel electronic/spintronic devices.


title: Exact tail asymptotics for a discrete-time preemptive priority queue

abstract:
  In this paper, we consider a discrete-time preemptive priority queue with
different service rates for two classes of customers, one with high-priority
and the other with low-priority. This model corresponds to the classical
preemptive priority queueing system with two classes of independent Poisson
customers and a single exponential server. Due to the possibility of customers'
arriving and departing at the same time in a discrete-time queue, the model
considered in this paper is more complicated. In this model, we focus on the
characterization of exact tail asymptotics for the joint stationary
distribution of the queue length of the two classes of customers, for the two
boundary distributions and for the two marginal distributions, respectively. By
using generating functions and kernel method, we get an explicit expression of
exact tail asymptotics along the low-priority queue direction, as well as along
the high-priority queue direction.


title: CPT Groups of Spinor Fields in de Sitter and Anti-de Sitter Spaces

abstract:
  $CPT$ groups for spinor fields in de Sitter and anti-de Sitter spaces are
defined in the framework of automorphism groups of Clifford algebras. It is
shown that de Sitter spaces with mutually opposite signatures correspond to
Clifford algebras with different algebraic structure that induces an essential
difference of $CPT$ groups associated with these spaces. $CPT$ groups for
charged particles are considered with respect to phase factors on the various
spinor spaces related with real subalgebras of the simple Clifford algebra over
the complex field (Dirac algebra). It is shown that $CPT$ groups for neutral
particles which admit particle-antiparticle interchange and $CPT$ groups for
truly neutral particles are described within semisimple Clifford algebras with
quaternionic and real division rings, respectively. A difference between
bosonic and fermionic $CPT$ groups is discussed.


title:
Prediction of heart rate response to conclusion of spontaneous breathing
  trial by fluctuation dissipation theory

abstract:
  The non-equilibrium fluctuation dissipation theorem is applied to predict how
critically ill patients respond to treatment, based upon data currently
collected by standard hospital monitoring devices. This framework is
demonstrated on a common procedure in critical care: the spontaneous breathing
trial. It is shown that the responses of groups of similar patients to the
spontaneous breathing trial can be predicted by the non-equilibrium fluctuation
dissipation approach. This mathematical framework, when fully formed and
applied to other clinical interventions, may serve as part of the basis for
personalized critical care.


title: Notes on Cohomologies of Lie Triple Systems

abstract:
  The cohomology theory of Lie triple systems in the sense of Yamaguti is
studied by means of cohomology of Leibniz algebras in the sense of Loday. The
notion of Nijenhuis operators for Lie triple system is introduced to describe
trivial deformations. We also study the abelian extensions of Lie triple
systems in details.


title: Foliations, orders, representations, L-spaces and graph manifolds

abstract:
  We show that the properties of admitting a co-oriented taut foliation and
having a left-orderable fundamental group are equivalent for rational homology
$3$-sphere graph manifolds and relate them to the property of not being a
Heegaard-Floer L-space. This is accomplished in several steps. First we show
how to detect families of slopes on the boundary of a Seifert fibred manifold
in four different fashions - using representations, using left-orders, using
foliations, and using Heegaard-Floer homology. Then we show that each method of
detection determines the same family of detected slopes. Next we provide
necessary and sufficient conditions for the existence of a co-oriented taut
foliation on a graph manifold rational homology $3$-sphere, respectively a
left-order on its fundamental group, which depend solely on families of
detected slopes on the boundaries of its pieces. The fact that Heegaard-Floer
methods can be used to detect families of slopes on the boundary of a Seifert
fibred manifold combines with certain conjectures in the literature to suggest
an L-space gluing theorem for rational homology $3$-sphere graph manifolds as
well as other interesting problems in Heegaard-Floer theory.


title:
Security Evaluation of Support Vector Machines in Adversarial
  Environments

abstract:
  Support Vector Machines (SVMs) are among the most popular classification
techniques adopted in security applications like malware detection, intrusion
detection, and spam filtering. However, if SVMs are to be incorporated in
real-world security systems, they must be able to cope with attack patterns
that can either mislead the learning algorithm (poisoning), evade detection
(evasion), or gain information about their internal parameters (privacy
breaches). The main contributions of this chapter are twofold. First, we
introduce a formal general framework for the empirical evaluation of the
security of machine-learning systems. Second, according to our framework, we
demonstrate the feasibility of evasion, poisoning and privacy attacks against
SVMs in real-world security problems. For each attack technique, we evaluate
its impact and discuss whether (and how) it can be countered through an
adversary-aware design of SVMs. Our experiments are easily reproducible thanks
to open-source code that we have made available, together with all the employed
datasets, on a public repository.


title: A Simple Method to Reduce Thermodynamic Derivatives by Computer

abstract:
  Studies in thermodynamics often require the reduction of some first or second
order partial derivatives in terms of a smaller basic set. A simple algorithm
to perform such a reduction is presented here, together with a review of
earlier related works. The algorithm uses Jacobians and is written in Maple
language, but it is easily translated in terms of any other computer algebra
language.


title:
Nucleation and growth by diffusion under Ostwald-Freundlich boundary
  condition

abstract:
  The critical radius of a nucleus grown by diffusion in a solution is studied
thermodynamically as well as kinetically. The thermodynamic growth equation
called Zeldovich equation of classical nucleation theory (CNT) and the kinetic
diffusional growth equation combined with the Ostwald-Freundlich boundary
condition lead to the same critical radius. However, it should be pointed out
that the diffusional equation may lead to a kinetic critical radius that is
different from the thermodynamic critical radius, thus indicating the
possibility of kinetically controlling the critical radius of a nucleus.


title: Photon Emission from a Cavity-Coupled Double Quantum Dot

abstract:
  We study a voltage biased InAs double quantum dot (DQD) that is coupled to a
superconducting transmission line resonator. Inelastic tunneling in the DQD is
mediated by electron phonon coupling and coupling to the cavity mode. We show
that electronic transport through the DQD leads to photon emission from the
cavity at a rate of 10 MHz. With a small cavity drive field, we observe a gain
of up to 15 in the cavity transmission. Our results are analyzed in the context
of existing theoretical models and suggest that it may be necessary to account
for inelastic tunneling processes that proceed via simultaneous emission of a
phonon and a photon.


title:
Quantization of systems with temporally varying discretization II: Local
  evolution moves

abstract:
  Several quantum gravity approaches and field theory on an evolving lattice
involve a discretization changing dynamics generated by evolution moves. Local
evolution moves in variational discrete systems (1) are a generalization of the
Pachner evolution moves of simplicial gravity models, (2) update only a small
subset of the dynamical data, (3) change the number of kinematical and physical
degrees of freedom, and (4) generate a dynamical coarse graining or refining of
the underlying discretization. To systematically explore such local moves and
their implications in the quantum theory, this article suitably expands the
quantum formalism for global evolution moves, constructed in a companion paper,
by employing that global moves can be decomposed into sequences of local moves.
This formalism is spelled out for systems with Euclidean configuration spaces.
Various types of local moves, the different kinds of constraints generated by
them, the constraint preservation and possible divergences in resulting state
sums are discussed. It is shown that non-trivial local coarse graining moves
entail a non-unitary projection of (physical) Hilbert spaces and `fine grained'
Dirac observables defined on them. Identities for undoing a local evolution
move with its (time reversed) inverse are derived. Finally, the implications of
these results for a Pachner move generated dynamics in simplicial quantum
gravity models are commented on.


title:
Visualization of atomic-scale phenomena in superconductors: application
  to FeSe

abstract:
  We propose a simple method of calculating inhomogeneous, atomic-scale
phenomena in superconductors which makes use of the wave function information
traditionally discarded in the construction of tight-binding models used in the
Bogoliubov-de Gennes equations. The method uses symmetry based first principles
Wannier functions to visualize the effects of superconducting pairing on the
distribution of electronic states over atoms within a crystal unit cell. Local
symmetries lower than the global lattice symmetry can thus be exhibited as
well, rendering theoretical comparisons with scanning tunneling spectroscopy
data much more useful. As a simple example, we discuss the geometric dimer
states observed near defects in superconducting FeSe.


title: Security Implications of Distributed Database Management System Models

abstract:
  Security features must be addressed when escalating a distributed database.
The choice between the object oriented and the relational data model, several
factors should be considered. The most important of these factors are single
and multilevel access controls (MAC), protection and integrity maintenance.
While determining which distributed database replica will be more secure for a
particular function, the choice should not be made exclusively on the basis of
available security features. One should also query the effectiveness and
efficiency of the delivery of these characteristics. In this paper, the
security strengths and weaknesses of both database models and the thorough
problems initiate in the distributed environment are conversed.


title:
Radiation pressure and the linear momentum of the electromagnetic field
  in magnetic media

abstract:
  We examine the force of the electromagnetic radiation on linear, isotropic,
homogeneous media specified in terms of their permittivity epsilon and
permeability mu. A formula is proposed for the electromagnetic Lorentz force on
the magnetization M, which is treated here as an Amperian current loop. Using
the proposed formula, we demonstrate conservation of momentum in several cases
that are amenable to rigorous analysis based on the classical Maxwell
equations, the Lorentz law of force, and the constitutive relations. Our
analysis yields precise expressions for the density of the electromagnetic and
mechanical momenta inside the media that are specified by their (epsilon, mu)
parameters. An interesting consequence of this analysis is the identification
of an "intrinsic" mechanical momentum density, ExM/c^2, analogous to the
electromagnetic (or Abraham) momentum density, ExH/c^2. (Here E and H are the
magnitudes of the electric and magnetic fields, respectively, and c is the
speed of light in vacuum.) This intrinsic mechanical momentum, associated with
the magnetization M in the presence of an electric field E, is apparently the
same "hidden" momentum that was predicted by W. Shockley and R.P. James nearly
four decades ago.


title:
SPRING: speech and pronunciation improvement through games, for Hispanic
  children

abstract:
  Lack of proper English pronunciations is a major problem for immigrant
population in developed countries like U.S. This poses various problems,
including a barrier to entry into mainstream society. This paper presents a
research study that explores the use of speech technologies merged with
activity-based and arcade-based games to do pronunciation feedback for Hispanic
children within the U.S. A 3-month long study with immigrant population in
California was used to investigate and analyze the effectiveness of computer
aided pronunciation feedback through games. In addition to quantitative
findings that point to statistically significant gains in pronunciation
quality, the paper also explores qualitative findings, interaction patterns and
challenges faced by the researchers in dealing with this community. It also
describes the issues involved in dealing with pronunciation as a competency.


title:
Superdeformed $\Lambda$ hypernuclei with antisymmetrized molecular
  dynamics

abstract:
  The response to the addition of a $\Lambda$ hyperon is investigated for the
deformed states such as superdeformation in $^{41}_\Lambda$Ca, $^{46}_\Lambda
$Sc and $^{48}_\Lambda$Sc. In the present study, we use the antisymmetrized
molecular dynamics (AMD) model. It is pointed out that many kinds of deformed
bands appear in $^{45}$Sc and $^{47}$Sc. Especially, it is found that there
exists superdeformed states in $^{45}$Sc. By the addition of a $\Lambda$
particle to $^{40}$Ca, $^{45}$Sc and $^{47}$Sc, it is predicted, for the first
time, that the superdeformed states exist in the hypernuclei $^{41}_\Lambda$Ca
and $^{46}_\Lambda$Sc. The manifestation of the dependence of the
$\Lambda$-separation energy on nuclear deformation such as spherical, normal
deformation and superdeformation is shown in the energy spectra of
$^{41}_\Lambda$Ca, $^{46}_\Lambda $Sc and $^{48}_\Lambda$Sc hypernuclei.


title: Polynomials with prescribed bad primes

abstract:
  We tabulate polynomials in Z[t] with a given factorization partition, bad
reduction entirely within a given set of primes, and satisfying auxiliary
conditions associated to 0, 1, and infinity. We explain how these sets of
polynomials are of particular interest because of their role in the
construction of nonsolvable number fields of arbitrarily large degree and
bounded ramification. Finally we discuss the similar but technically more
complicated tabulation problem corresponding to removing the auxiliary
conditions.


title: The role of planetesimal fragmentation on giant planet formation

abstract:
  In the standard scenario of planet formation, terrestrial planets and the
cores of the giant planets are formed by accretion of planetesimals. As
planetary embryos grow the planetesimal velocity dispersion increases due to
gravitational excitations produced by embryos. The increase of planetesimal
relative velocities causes the fragmentation of them due to mutual collisions.
  We study the role of planetesimal fragmentation on giant planet formation. We
analyze how planetesimal fragmentation modifies the growth of giant planet's
cores for a wide range of planetesimal sizes and disk masses.
  We incorporate a model of planetesimal fragmentation into our model of in
situ giant planet formation. We calculate the evolution of the solid surface
density (planetesimals plus fragments) due to the accretion by the planet,
migration and fragmentation.
  The incorporation of planetesimal fragmentation significantly modifies the
process of planetary formation. If most of the mass loss in planetesimal
collisions is distributed in the smaller fragments, planetesimal fragmentation
inhibits the growth of the embryo for initial planetesimals of radii lower than
10 km. Only for initial planetesimals of 100 km of radius, and disks greater
than 0.06 Msun, embryos achieve masses greater than the mass of the Earth.
However, even for such big planetesimals and massive disks, planetesimal
fragmentation induces the quickly formation of massive cores only if most of
the mass loss in planetesimal collisions is distributed in the bigger
fragments.
  Planetesimal fragmentation seems to play an important role in giant planet
formation. The way in which the mass loss in planetesimal collisions is
distributed leads to different results, inhibiting or favoring the formation of
massive cores.


title:
Stability robustness of a feedback interconnection of systems with
  negative imaginary frequency response

abstract:
  A necessary and sufficient condition, expressed simply as the DC loop gain
(ie the loop gain at zero frequency) being less than unity, is given in this
paper to guarantee the internal stability of a feedback interconnection of
Linear Time-Invariant (LTI) Multiple-Input Multiple-Output (MIMO) systems with
negative imaginary frequency response. Systems with negative imaginary
frequency response arise for example when considering transfer functions from
force actuators to co-located position sensors, and are commonly important in
for example lightly damped structures. The key result presented here has
similar application to the small-gain theorem, which refers to the stability of
feedback interconnections of contractive gain systems, and the passivity
theorem (or more precisely the positive real theorem in the LTI case), which
refers to the stability of feedback interconnections of positive real systems.
A complete state-space characterisation of systems with negative imaginary
frequency response is also given in this paper and also an example that
demonstrates the application of the key result is provided.


title:
Investigating formation condition of primordial black holes for
  generalized initial perturbation profiles

abstract:
  Primordial black holes (PBHs) are an important tool in cosmology to probe the
primordial spectrum of small-scale curvature perturbations that reenter the
cosmological horizon during radiation domination epoch. We numerically solve
the evolution of spherically symmetric highly perturbed configurations to
clarify the criteria of PBHs formation using a wide class of curvature profiles
characterized by five parameters. It is shown that formation or non-formation
of PBHs is determined essentialy by only two master parameters.


title:
ReducedCBT and SuperCBT, Two New and Improved Complete Binary Tree
  Structures

abstract:
  Between the leaves and the nodes of a complete binary tree, a separate
parent-child-sister hierarchy is employed independent of the
parent-child-sister hierarchy used for the rest of the tree. Two different
versions of such a local hierarchy are introduced. The result of the first
proposed hierarchy is a faster and smaller footprint, while the second one
provides the size variation functionality without a significant computational
overhead. This novel approach brings considerable memory gains and performance
boosts to the complete binary tree based algorithms.


title:
Even-denominator Fractional Quantum Hall Effect at a Landau Level
  Crossing

abstract:
  The fractional quantum Hall effect (FQHE), observed in two-dimensional (2D)
charged particles at high magnetic fields, is one of the most fascinating,
macroscopic manifestations of a many-body state stabilized by the strong
Coulomb interaction. It occurs when the filling factor ($\nu$) of the quantized
Landau levels (LLs) is a fraction which, with very few exceptions, has an odd
denominator. In 2D systems with additional degrees of freedom it is possible to
cause a crossing of the LLs at the Fermi level. At and near these crossings,
the FQHE states are often weakened or destroyed. Here we report the observation
of an unusual crossing of the two \emph{lowest-energy} LLs in high-mobility
GaAs 2D $hole$ systems which brings to life a new \emph{even-denominator} FQHE
at $\nu=1/2$.


title:
Effective Features of Remote Sensing Image Classification Using
  Interactive Adaptive Thresholding Method

abstract:
  Remote sensing image classification can be performed in many different ways
to extract meaningful features. One common approach is to perform edge
detection. A second approach is to try and detect whole shapes, given the fact
that these shapes usually tend to have distinctive properties such as object
foreground or background. To get optimal results, these two approaches can be
combined. This paper adopts a combinatorial optimization method to adaptively
select threshold based features to improve remote sensing image. Feature
selection is an important combinatorial optimization problem in the remote
sensing image classification. The feature selection method has to achieve three
characteristics: first the performance issues by facilitating data collection
and reducing storage space and classification time, second to perform semantics
analysis helping to understand the problem, and third to improve prediction
accuracy by avoiding the curse of dimensionality. The goal of this thresholding
an image is to classify pixels as either dark or light and evaluation of
classification results. Interactive adaptive thresholding is a form of
thresholding that takes into account spatial variations in illumination of
remote sensing image. We present a technique for remote sensing based adaptive
thresholding using the interactive satellite image of the input. However, our
solution is more robust to illumination changes in the remote sensing image.
Additionally, our method is simple and easy to implement but it is effective
algorithm to classify the image pixels. This technique is suitable for
preprocessing the remote sensing image classification, making it a valuable
tool for interactive remote based applications such as augmented reality of the
classification procedure.


title:
Collective eigenstates of emission in an N-entity heterostructure and
  the evaluation of its Green tensors and self-energy components

abstract:
  Our understanding of emission from a collection of emitters strongly
interacting among them and also with other polarizable matter in proximity has
been approximated by independent emission from the emitters. This is primarily
due to our inability to evaluate the self-energy matrices and the collective
eigenstates of emitters in heterogeneous ensembles. A method to evaluate the
self-energy matrices that is not limited by the geometry and the material
composition is presented here to understand and exploit such collective
excitations. Numerical evaluations using this method are used to highlight the
significant differences between independent and the collective modes of
emission in heterostructures. A set of n emitters driving each other and m
other polarizable entities, where N=m+n, is used to represent the coupled
system of a generalized geometry in a volume integral approach. Closed form
relations between the Green tensors of entity pairs in free space and their
correspondents in a heterostructure are derived concisely. This is made
possible for general geometries because the global matrices consisting of all
free-space Green dyads are subject to conservation laws. The self-energy matrix
of the emitters can then be assembled using the evaluated Green tensors of the
heterostructure, but a decomposition of its components into their radiative and
non-radiative decay contributions is non-trivial. This is accomplished using
matrix decomposition identities applied to the global matrices containing all
free-space dyads. The relations to compute the observables of the eigenstates
(such as quantum efficiency, power/energy of emission, radiative and
non-radiative decay rates) are presented. We conclude with a note on extension
of this method to collective excitations that also include strong interactions
with a surface in the near-field.


title:
Feedback Control of Negative-Imaginary Systems: Large Flexible
  structures with colocated actuators and sensors

abstract:
  This paper presents a survey of recent results on the theory of negative
imaginary systems. This theory can be applied to the robust control of large
flexible structures with colocated force actuators and position sensors.


title:
Processes of heavy quark pair (lepton pair) and two gluon (two photon)
  production in the high energy quark (electron) proton peripheral collisions

abstract:
  We considered the three jet production processes in the region of the
incident lepton, photon, quark or gluon fragmentation. The fourth jet is
created by the recoil proton. The kinematics of jet production is discussed in
jets production in the fragmentation region. The non-trivial relation between
the momenta of the recoil proton and the polar angle of its emission was
derived.
  Based on this formalism the differential cross sections of QCD processes $gp
\to (ggg) p; \,\,\,qp \to (q \bar{Q} Q) p; \,\,\, gp \to (g Q \bar{Q})p$ were
obtained, including the distribution on transverse momentum component of jets
fragments. It was shown that the role of the contribution of "non-Abelian"
nature may become dominant in a particular kinematics of the final particles.
The kinematics, in which the initial particle changes the direction of movement
to the opposite one, was considered in the case of heavy quark-antiquark pair
production.
  Different distributions, including spectral, azimuthal and polar angle
distribution on the fragments of jets can be arranged using our results. We
present besides the behavior of the ratio of non-Abelian contribution to the
cross section to the total contribution. We show that it dominates for large
values of the transverse momenta of jets component (gluons or quarks). Some
historical introduction to the cross-sections of peripheral processes,
including 2$\gamma$ creation mechanism production, including the result
Brodsky-Kinoshita-Terazawa, is given.


title:
Dependence of the residual surface resistance of superconducting RF
  cavities on the cooling dynamics around $T_\mathrm{c}$

abstract:
  We report a strong effect of the cooling dynamics through $T_\mathrm{c}$ on
the amount of trapped external magnetic flux in superconducting niobium
cavities. The effect is similar for fine grain and single crystal niobium and
all surface treatments including electropolishing with and without 120$^\circ$C
baking and nitrogen doping. Direct magnetic field measurements on the cavity
walls show that the effect stems from changes in the flux trapping efficiency:
slow cooling leads to almost complete flux trapping and higher residual
resistance while fast cooling leads to the much more efficient flux expulsion
and lower residual resistance.


title: Non-Simplicial Nerves for Two-Dimensional Categorical Structures

abstract:
  The most natural notion of a simplicial nerve for a (weak) bicategory was
given by Duskin, who showed that a simplicial set is isomorphic to the nerve of
a $(2,1)$-category (i.e. a bicategory with invertible $2$-morphisms) if and
only if it is a quasicategory which has unique fillers for inner horns of
dimension $3$ and greater. Using Duskin's technique, we show how his nerve
applies to $(2,1)$-category functors, making it a fully faithful inclusion of
$(2,1)$-categories into simplicial sets. Then we consider analogues of this
extension of Duskin's result for several different two-dimensional categorical
structures, defining and analysing nerves valued in presheaf categories based
on $\Delta^2$, on Segal's category $\Gamma$, and Joyal's category $\Theta_2$.
In each case, our nerves yield exactly those presheaves meeting a certain
"horn-filling" condition, with unique fillers for high-dimensional horns.
Generalizing our definitions to higher dimensions and relaxing this uniqueness
condition, we get proposed models for several different kinds
higher-categorical structures, with each of these models closely analogous to
quasicategories. Of particular interest, we conjecture that our "inner-Kan
$\Gamma$-sets'' are a combinatorial model for symmetric monoidal
$(\infty,0)$-categories, i.e. $E_\infty$-spaces.
  This is a version of the author's Ph.D. dissertation, completed 2013 at the
University of California, Berkeley. Minor corrections and changes are included.


title:
Quantitative Decoding of Interactions in Tunable Nanomagnet Arrays Using
  First Order Reversal Curves

abstract:
  To develop a full understanding of interactions in nanomagnet arrays is a
persistent challenge, critically impacting their technological acceptance. This
paper reports the experimental, numerical and analytical investigation of
interactions in arrays of Co nanoellipses using the first-order reversal curve
(FORC) technique. A mean-field analysis has revealed the physical mechanisms
giving rise to all of the observed features: a shift of the non-interacting
FORC-ridge at the low-H$_c$ end off the local coercivity H$_c$ axis; a stretch
of the FORC-ridge at the high-H$_c$ end without shifting it off the H$_c$ axis;
and a formation of a tilted edge connected to the ridge at the low-H$_c$ end.
Changing from flat to Gaussian coercivity distribution produces a negative
feature, bends the ridge, and broadens the edge. Finally, nearest neighbor
interactions segment the FORC-ridge. These results demonstrate that the FORC
approach provides a comprehensive framework to qualitatively and quantitatively
decode interactions in nanomagnet arrays.