title:
Rest-frame optical properties of luminous, radio-selected, broad
  absorption line quasars

abstract:
  We have obtained IRTF/SpeX spectra of eight moderate-redshift (z=0.7-2.4),
radio-selected (log R*~0.4-1.9) broad absorption line (BAL) quasars. The
spectra cover the rest-frame optical band. We compare the optical properties of
these quasars to those of canonically radio-quiet (log R*<1) BAL quasars at
similar redshifts and to low-redshift quasars from the Palomar-Green catalog.
As with previous studies of BAL quasars, we find that [OIII] 5007 is weak, and
optical FeII emission is strong, a rare combination in canonically radio-loud
(log R*>1) quasars. With our measurements of the optical properties,
particularly the Balmer emission line widths and the continuum luminosity, we
have used empirical scaling relations to estimate black hole masses and
Eddington ratios. These lie in the range (0.4-2.6)x10^9 M_sun and 0.1-0.9,
respectively. Despite their comparatively extreme radio properties relative to
most BAL quasars, their optical properties are quite consistent with those of
radio-quiet BAL quasars and dissimilar to those of radio-loud non-BAL quasars.
While BAL quasars generally appear to have low values of [OIII]/FeII, an
extreme of "Eigenvector 1", the Balmer line widths and Eddington ratios do not
appear to significantly differ from those of unabsorbed quasars at similar
redshifts and luminosities.


title:
Reconstructing the Profile of Time-Varying Magnetic Fields With Quantum
  Sensors

abstract:
  Quantum systems have shown great promise for precision metrology thanks to
advances in their control. This has allowed not only the sensitive estimation
of external parameters but also the reconstruction of their temporal profile.
In particular, quantum control techniques and orthogonal function theory have
been applied to the reconstruction of the complete profiles of time-varying
magnetic fields. Here, we provide a detailed theoretical analysis of the
reconstruction method based on the Walsh functions, highlighting the
relationship between the orthonormal Walsh basis, sensitivity of field
reconstructions, data compression techniques, and dynamical decoupling theory.
Specifically, we show how properties of the Walsh basis and a detailed
sensitivity analysis of the reconstruction protocol provide a method to
characterize the error between the reconstructed and true fields. In addition,
we prove various results about the negligibility function on binary sequences
which lead to data compression techniques in the Walsh basis and a more
resource-efficient reconstruction protocol. The negligibility proves a fruitful
concept to unify the information content of Walsh functions and their dynamical
decoupling power, which makes the reconstruction method robust against noise.


title:
Riemann-Schwarz Reflection Principle and Asymptotics of Modules of
  Rectangular Frames

abstract:
  We investigate asymptotical behavior of the conformal module of a
doubly-connected domain which is the difference of two homothetic rectangles
under stretching it along the abscissa axis. Thereby, we give the answer to a
question put by Prof. M.Vuorinen.


title: Sub-PeV Neutrinos from TeV Unidentified Sources in the Galaxy

abstract:
  The IceCube collaboration discovery of 28 high-energy neutrinos over the
energy range 30 TeV <~ E_nu <~ 1 PeV, a 4.3-sigma excess over expected
backgrounds, represents the first high-confidence detection of cosmic neutrinos
at these energies. In light of this discovery, we explore the possibility that
some of the Sub-PeV cosmic neutrinos might originate in our Galaxy's TeV
unidentified (TeV UnID) sources. While typically resolved at TeV energies,
these sources lack prominent radio or X-ray counterparts, and so have been
considered promising sites for hadron acceleration within our Galaxy. Modeling
the TeV UnID sources as Galactic hypernova remnants, we predict Sub-PeV
neutrino fluxes and spectra consistent with their contributing a minority of
n_nu <~ 2 of the observed events. This is consistent with our analysis of the
spatial distribution of the Sub-PeV neutrinos and TeV UnID sources, which finds
that a best-fit of one, and maximum of 3.8 (at 90%-confidence), of the ~16
non-atmospheric Sub-PeV neutrinos may originate in TeV UnID sources, with the
remaining 75% to 95% of events being drawn from an isotropic background. If our
scenario is correct, we expect excess Sub-PeV neutrinos to accumulate along the
Galactic plane, within |l| <~ 30 deg of the Galactic center and in the Cygnus
region, as observations by IceCube and other high-energy neutrino facilities go
forward. Our scenario also has implications for radio, X-ray, and TeV
observations of the TeV UnID sources.


title:
The bright end of the exo-Zodi luminosity function: Disk evolution and
  implications for exo-Earth detectability

abstract:
  We present the first characterisation of the 12um warm dust ("exo-Zodi")
luminosity function around Sun-like stars, focussing on the dustiest systems
that can be identified by WISE. We detect six new warm dust candidates, five of
which have unknown ages. We show that the dustiest old (>Gyr) systems like
BD+20 307 are 1 in 10,000 occurrences. Bright warm dust is more common around
young (<120Myr) systems, with a ~1% occurrence rate. We show that a two
component in situ model where all stars have initially massive warm disks and
in which warm debris is also generated at some random time along the stars'
main-sequence lifetime, perhaps due to a collision, can explain the
observations. However, if all stars only have initially massive warm disks
these would not be visible at Gyr ages, and random collisions on the
main-sequence are too infrequent to explain the high disk occurrence rate for
young stars. That is, neither component can explain the observations on their
own. Despite these conclusions, we cannot rule out an alternative model in
which comets are scattered from outer regions because the distribution of
systems with the appropriate dynamics is unknown. Our in situ model predicts
the fraction of stars with exo-Zodi bright enough to cause problems for future
exo-Earth imaging attempts is at least ~10%, and is higher for populations of
stars younger than a few Gyr. This prediction of ~10% applies to old stars
because bright systems like BD+20 307 imply a population of fainter systems
that were once bright but are now decaying through fainter levels. Our
prediction should be strongly tested by the Large Binocular Telescope
Interferometer, providing valuable input for more detailed evolution models. A
detection fraction lower than our prediction could indicate that the hot dust
in systems like BD+20 307 has a cometary origin due to the quirks of the
planetary dynamics.


title: Minimal Signatures of Naturalness

abstract:
  We study the naturalness problem using a model independent bottom up approach
by considering models where only the interaction terms needed to cancel the
Higgs quadratic divergences are present. If quadratic divergences are canceled
by terms linear in the Higgs field, then the collider phenomenology is well
covered by current electroweakino and fourth generation searches. If quadratic
divergences are canceled by terms bilinear in the Higgs field, then the
signatures are highly dependent on the quantum numbers of the new particles.
Precision Higgs measurements can reveal the presence of new particles with
either vevs or Standard Model charges. If the new particles are scalar dark
matter candidates, their direct and indirect detection signatures will be
highly correlated and within the reach of XENON100 and Fermi. Observation at
one of these experiments would imply observation at the other one. Observable
LHC decay channels can also arise if the new particles mix with lighter states.
This decay channel involves only the Higgs boson and not the gauge bosons.
Observation of such decays would give evidence that the new particle is tied to
the naturalness problem.


title:
Particle Physics Implications and Constraints on Dark Matter
  Interpretations of the CDMS Signal

abstract:
  Recently the CDMS collaboration has reported an excess of events in the
signal region of a search for dark matter scattering with Silicon nuclei. Three
events on an expected background of 0.4 have a significance of about 2 sigma,
and it is premature to conclude that this is a signal of dark matter.
Nonetheless, it is important to examine the space of particle theories capable
of explaining this excess, to see what theories are capable of explaining it,
and how one might exclude it or find corroborating evidence in other channels.
We examine a simplified model containing a scalar mediator particle, and find
regions consistent with the CDMS observations. Bounds from colliders put
important restrictions on the theory, but viable points, including points
leading to the observed thermal relic density, survive.


title: A strong electroweak phase transition in the 2HDM after LHC8

abstract:
  The nature of the electroweak phase transition in two-Higgs-doublet models is
revisited in light of the recent LHC results. A scan over an extensive region
of their parameter space is performed, showing that a strongly first-order
phase transition favours a light neutral scalar with SM-like properties,
together with a heavy pseudo-scalar (m_A^0 > 400 GeV) and a mass hierarchy in
the scalar sector, m_H^+ < m_H^0 < m_A^0. We also investigate the h^0 -> gamma
gamma decay channel and find that an enhancement in the branching ratio is
allowed, and in some cases even preferred, when a strongly first-order phase
transition is required.


title: Can we reproduce the X-ray background spectral shape using local AGN?

abstract:
  The X-ray background (XRB) is due to the aggregate of active galactic nuclei
(AGN), which peak in activity at z~1 and is often modeled as the sum of
different proportions of unabsorbed, moderately- and heavily-absorbed AGN. We
present the summed spectrum of a complete sample of local AGN (the Northern
Galactic Cap of the 58-month Swift/BAT catalog, z<0.2) using 0.4-200keV data
and directly determine the different proportions of unabsorbed, moderately and
heavily-absorbed AGN that make up the summed spectrum. This stacked low
redshift AGN spectrum is remarkably similar in shape to the XRB spectrum (when
shifted to z~1), but the observed proportions of different absorption
populations differ from most XRB synthesis models. AGN with Compton-thick
absorption account for only ~12% of the sample, but produce a significant
contribution to the overall spectrum. We confirm that Compton reflection is
more prominent in moderately-absorbed AGN and that the photon index differs
intrinsically between unabsorbed and absorbed AGN. The AGN in our sample
account for only ~1% of the XRB intensity. The reproduction of the XRB spectral
shape suggests that strong evolution in individual AGN properties is not
required between z~0 and 1.


title: A flavour GUT model with theta_13^PMNS = theta_C / sqrt(2)

abstract:
  We propose a supersymmetric SU(5) GUT model with an A_4 family symmetry -
including a full flavon- and messenger sector - which realises the relation
theta_13^PMNS \simeq theta_C / sqrt(2). The neutrino sector features
tri-bimaximal mixing, and theta_13^PMNS \simeq theta_C / sqrt(2) emerges from
the charged lepton contribution to the PMNS matrix, which in turn is linked to
quark mixing via specific GUT relations. These GUT relations arise after GUT
symmetry breaking from a novel combination of group theoretical Clebsch-Gordan
factors, which in addition to large theta_13^PMNS lead to promising quark
lepton mass ratios for all generations of quarks and leptons and to m_s / m_d =
18.95_(-0.24)^(+0.33), in excellent agreement with experimental results. The
model also features spontaneous CP violation, with all quark and lepton CP
phases determined from family symmetry breaking. We perform a full Markov Chain
Monte Carlo fit to the available quark and lepton data, and discuss how the
model can be tested by present and future experiments.


title:
Dynamical invariants and diffusion of merger substructures in
  time-dependent gravitational potentials

abstract:
  This paper explores a mathematical technique for deriving dynamical
invariants (i.e. constants of motion) in time-dependent gravitational
potentials. The method relies on the construction of a canonical transformation
that removes the explicit time-dependence from the Hamiltonian of the system.
By referring the phase-space locations of particles to a coordinate frame in
which the potential remains `static' the dynamical effects introduced by the
time evolution vanish. It follows that dynamical invariants correspond to the
integrals of motion for the static potential expressed in the transformed
coordinates. The main difficulty of the method reduces to solving the
differential equations that define the canonical transformation, which are
typically coupled with the equations of motion. We discuss a few examples where
both sets of equations can be exactly de-coupled, and cases that require
approximations. The construction of dynamical invariants has far-reaching
applications. These quantities allow us, for example, to describe the evolution
of (statistical) microcanonical ensembles in time-dependent gravitational
potentials without relying on ergodicity or probability assumptions. As an
illustration, we follow the evolution of dynamical fossils in galaxies that
build up mass hierarchically. It is shown that the growth of the host potential
tends to efface tidal substructures in the integral-of-motion space through an
orbital diffusion process. The inexorable cycle of deposition, and progressive
dissolution, of tidal clumps naturally leads to the formation of a `smooth'
stellar halo.


title: Advanced Quantum Noise

abstract:
  We use the quantum correlations of twin-beams of light to probe the added
noise when one of the beams propagates through a medium with anomalous
dispersion. The experiment is based on two successive four-wave mixing
processes in rubidium vapor, which allow for the generation of bright
two-mode-squeezed twin-beams followed by a controlled advancement while
maintaining the shared quantum-correlations between the beams. The demonstrated
effect allows the study of irreversible decoherence in a medium exhibiting
anomalous dispersion, and for the first time shows the advancement of a bright
nonclassical state of light. The advancement and corresponding degradation of
the quantum correlations are found to be operating near the fundamental quantum
limit imposed by using a phase-insensitive amplifier.


title:
Pulse Profiles from Spinning Neutron Stars in the Hartle-Thorne
  Approximation

abstract:
  We present a new numerical algorithm for the calculation of pulse profiles
from spinning neutron stars in the Hartle-Thorne approximation. Our approach
allows us to formally take into account the effects of Doppler shifts and
aberration, of frame dragging, as well as of the oblateness of the stellar
surface and of its quadrupole moment. We confirm an earlier result that
neglecting the oblateness of the neutron-star surface leads to ~5-30% errors in
the calculated profiles and further show that neglecting the quadrupole moment
of its spacetime leads to ~1-5% errors at a spin frequency of 600 Hz. We
discuss the implications of our results for the measurements of neutron-star
masses and radii with upcoming X-ray missions, such as NASA's NICER and ESA's
LOFT.


title: A refinement of Wilf-equivalence for patterns of length 4

abstract:
  In their paper \cite{DokosDwyer:Permutat12}, Dokos et al. conjecture that the
major index statistic is equidistributed among 1423-avoiding, 2413-avoiding,
and 2314-avoiding permutations. In this paper we confirm this conjecture by
constructing two major index preserving bijections, $\Theta:S_n(1423)\to
S_n(2413)$ and $\Omega:S_n(2314)\to S_n(2413)$. In fact, we show that $\Theta$
(respectively, $\Omega$) preserves numerous other statistics including the
descent set, right-to-left maximum (respectively, left-to-right minimum), and a
new statistic we call top-steps (respectively, bottom-steps).


title:
Electron-Ion Temperature Equilibration in Collisionless Shocks: the
  Supernova Remnant-Solar Wind Connection

abstract:
  Collisionless shocks are loosely defined as shocks where the transition
between pre-and post-shock states happens on a length scale much shorter than
the collisional mean free path. In the absence of collision to enforce thermal
equilibrium post-shock, electrons and ions need not have the same temperatures.
While the acceleration of electrons for injection into shock acceleration
processes to produce cosmic rays has received considerable attention, the
related problem of the shock heating of quasi-thermal electrons has been
relatively neglected. In this paper we review that state of our knowledge of
electron heating in astrophysical shocks, mainly associated with supernova
remnants (SNRs), shocks in the solar wind associated with the terrestrial and
Saturnian bowshocks, and galaxy cluster shocks. The solar wind and SNR samples
indicate that the ratio of electron temperature to ion temperature declines
with increasing shock speed or Alfvenic Mach number. We discuss the extent to
which such behavior can be understood via cosmic ray-generated waves in a shock
precursor, which then subsequently damp by heating electrons. Finally, we
speculate that a similar mechanism may be at work for both solar wind and SNR
shocks.


title: Elastic Platonic Shells

abstract:
  On microscopic scales, the crystallinity of flexible tethered or cross linked
membranes determines their mechanical response. We show that by controlling the
type, number and distribution of defects on a spherical elastic shell, it is
possible to direct the morphology of these structures. Our numerical
simulations show that by deflating a crystalline shell with defects, we can
create elastic shell analogs of the classical Platonic solids. These
morphologies arise via a sharp buckling transition from the sphere which is
strongly hysteretic in loading-unloading. We construct a minimal Landau theory
for the transition using quadratic and cubic invariants of the spherical
harmonic modes. Our approach suggests methods to engineer shape into soft
spherical shells using a frozen defect topology.


title:
Magnonic band gaps in waveguides with a periodic variation of the
  saturation magnetization

abstract:
  We present a micromagnetic analysis of spin-wave propagation in a magnonic
crystal realized as a permalloy spin-wave waveguide with a spatial periodical
variation of its saturation magnetization. Frequency band gaps were clearly
observed in the spin-wave transmission spectra and their origin is traced back
to an overlap of individual band gaps of the fundamental and the higher order
spin-wave width modes. The control of the depth, width and the position in
frequency and space of the rejection band gaps by the width areas with a
reduced magnetization and by the modulation level, are discussed in this study.


title: Denoising observational data

abstract:
  Reducing noise caused by the instrumentation in observational data is a
crucial step in data post-processing. A method is searched for that conserves
most of the instrumental resolution and introduces as few methodical artefacts
as possible. With such a method integrated in an observation sites software
tool-chain, the resources spent for the generation of observational data will
more likely find their way into resulting scientific publications; otherwise,
for data post-processing often methods are used, which just smear out the
noise, introduce artefacts, or decrease the provided resolution in space or
time. A short review of different techniques is given here, and a non-local
averaging method is applied to Hinode magnetograms and G-band data. The
presented method fits the needs for various kinds of observational data.


title: The arithmetic Tutte polynomials of the classical root systems

abstract:
  Many combinatorial and topological invariants of a hyperplane arrangement can
be computed in terms of its Tutte polynomial. Similarly, many invariants of a
hypertoric arrangement can be computed in terms of its arithmetic Tutte
polynomial. We compute the arithmetic Tutte polynomials of the classical root
systems of types A,B,C, and D, with respect to their integer, root, and weight
lattices. We do it in two ways: by introducing a finite field method for
arithmetic Tutte polynomials, and by enumerating signed graphs with respect to
six parameters.


title:
The Bolocam Galactic Plane Survey IX: Data Release 2 and Outer Galaxy
  Extension

abstract:
  We present a re-reduction and expansion of the Bolocam Galactic Plane Survey,
first presented by Aguirre et al. (2011) and Rosolowsky et al. (2010). The BGPS
is a 1.1 mm survey of dust emission in the Northern galactic plane, covering
longitudes -10 < \ell < 90 and latitudes |b| < 0.5 with a typical 1-\sigma RMS
sensitivity of 30-100 mJy in a 33" beam. Version 2 of the survey includes an
additional 20 square degrees of coverage in the 3rd and 4th quadrants and 2
square degrees in the 1st quadrant. The new data release has improved angular
recovery, with complete recovery out to 80" and partial recovery to 300", and
reduced negative bowls around bright sources resulting from the atmospheric
subtraction process. We resolve the factor of 1.5 flux calibration offset
between the v1.0 data release and other data sets and determine that there is
no offset between v2.0 and other data sets. The v2.0 pointing accuracy is
tested against other surveys and demonstrated to be accurate and an improvement
over v1.0. We present simulations and tests of the pipeline and its properties,
including measurements of the pipeline's angular transfer function. The Bolocat
cataloging tool was used to extract a new catalog, which includes 8594 sources,
with 591 in the expanded regions. We have demonstrated that the Bolocat 40" and
80" apertures are accurate even in the presence of strong extended background
emission. The number of sources is lower than in v1.0, but the amount of flux
and area included in identified sources is larger.


title:
Langevin dynamics in inhomogeneous media: Re-examining the
  It\^{o}-Stratonovich Dilemma

abstract:
  The diffusive dynamics of a particle in a medium with space-dependent
friction coefficient is studied within the framework of the inertial Langevin
equation. In this description, the ambiguous interpretation of the stochastic
integral, known as the It\^{o}-Stratonovich dilemma, is avoided since all
interpretations converge to the same solution in the limit of small time steps.
We use a newly developed method for Langevin simulations to measure the
probability distribution of a particle diffusing in a flat potential. Our
results reveal that both the It\^{o} and Stratonovich interpretations converge
very slowly to the uniform equilibrium distribution for vanishing time step
sizes. Three other conventions exhibit significantly improved accuracy: (i) the
"isothermal" (H\"{a}nggi) convention, (ii) the Stratonovich convention
corrected by a drift term, and (iii) a new convention employing two different
effective friction coefficients representing two different averages of the
friction function during the time step. We argue that the most physically
accurate dynamical description is provided by the third convention, in which
the particle experiences a drift originating from the dissipation instead of
the fluctuation term. This feature is directly related to the fact that the
drift is a result of an inertial effect that cannot be well understood in the
Brownian, overdamped limit of the Langevin equation.


title:
A TimeStamp based Multi-version STM Protocol that satisfies Opacity and
  Multi-Version Permissiveness

abstract:
  Software Transactional Memory Systems (STM) are a promising alternative to
lock based systems for concurrency control in shared memory systems. In
multiversion STM systems, each write on a transaction object produces a new
version of that object. The advantage obtained by storing multiple versions is
that one can ensure that read operations do not fail. Opacity is a commonly
used correctness criterion for STM systems. Multi-Version permissive STM system
never aborts a read-only transaction. Although many multi-version STM systems
have been proposed, to the best of our knowledge none of them have been
formally proved to satisfy opacity. In this paper we present a time-stamp based
multiversion STM system that satisfies opacity and mv-permissiveness. We
formally prove the correctness of the proposed STM system. We also present
garbage collection procedure which deletes unwanted versions of the transaction
objects and formally prove it correctness.


title: Classifying Quantum Phases With The Torus Trick

abstract:
  Classifying phases of local quantum systems is a general problem that
includes special cases such as free fermions, commuting projectors, and others.
An important distinction in this classification should be made between
classifying periodic and aperiodic systems. A related distinction is that
between homotopy invariants (invariants which remain constant so long as
certain general properties such as locality, gap, and others hold) and locally
computable invariants (properties of the system that cannot change from one
region to another without producing a gapless edge between them). We attack
this problem using a technique inspired by Kirby's "torus trick" in topology.
We use this trick to reproduce results for free fermions (in particular, using
the trick to reduce the aperiodic classification to the simpler problem of
periodic classification). We also show that a similar trick works for
interacting phases which are nontrivial but lack anyons; these results include
symmetry protected phases. A key part of this work is an attempt to classify
quantum cellular automata (QCA).

categories: cond-mat.str-el math-ph math.MP quant-ph


title: Robust Randomness Amplifiers: Upper and Lower Bounds

abstract:
  A recent sequence of works, initially motivated by the study of the nonlocal
properties of entanglement, demonstrate that a source of
information-theoretically certified randomness can be constructed based only on
two simple assumptions: the prior existence of a short random seed and the
ability to ensure that two black-box devices do not communicate (i.e. are
non-signaling). We call protocols achieving such certified amplification of a
short random seed randomness amplifiers.
  We introduce a simple framework in which we initiate the systematic study of
the possibilities and limitations of randomness amplifiers. Our main results
include a new, improved analysis of a robust randomness amplifier with
exponential expansion, as well as the first upper bounds on the maximum
expansion achievable by a broad class of randomness amplifiers. In particular,
we show that non-adaptive randomness amplifiers that are robust to noise cannot
achieve more than doubly exponential expansion. Finally, we show that a wide
class of protocols based on the use of the CHSH game can only lead to (singly)
exponential expansion if adversarial devices are allowed the full power of
non-signaling strategies. Our upper bound results apply to all known
non-adaptive randomness amplifier constructions to date.


title:
High quantum-efficiency photon-number-resolving detector for photonic
  on-chip information processing

abstract:
  The integrated optical circuit is a promising architecture for the
realization of complex quantum optical states and information networks. One
element that is required for many of these applications is a high-efficiency
photon detector capable of photon-number discrimination. We present an
integrated photonic system in the telecom band at 1550 nm based on UV-written
silica-on-silicon waveguides and modified transition-edge sensors capable of
number resolution and over 40% efficiency. Exploiting the mode transmission
failure of these devices, we multiplex three detectors in series to demonstrate
a combined 79% +/- 2% detection efficiency with a single pass, and 88% +/- 3%
at the operating wavelength of an on-chip terminal reflection grating.
Furthermore, our optical measurements clearly demonstrate no significant
unexplained loss in this system due to scattering or reflections. This
waveguide and detector design therefore allows the placement of
number-resolving single-photon detectors of predictable efficiency at arbitrary
locations within a photonic circuit - a capability that offers great potential
for many quantum optical applications.


title: A volume comparison theorem for asymptotically hyperbolic manifolds

abstract:
  We define a notion of renormalized volume of an asymptotically hyperbolic
manifold. Moreover, we prove a sharp volume comparison theorem for metrics with
scalar curvature at least -6. Finally, we show that the inequality is strict
unless the metric is isometric to one of the Anti-deSitter-Schwarzschild
metrics.


title:
Sedimentation stability and aging of aqueous dispersions of Laponite in
  the presence of cetyltrimethylammonium bromide

abstract:
  This work discusses the sedimentation stability and aging of aqueous
suspension of Laponite in the presence of cetyltrimethylammonium bromide
(CTAB). The concentration of Laponite was fixed at the constant level $C_l=2$
%wt, which corresponds to the threshold between equilibrium gel IG$_1$ and
repulsive gel IG$_2$ phases. The concentration of CTAB $C_s$ was within 0-0.3
%wt. In the presence of CTAB the Laponite aqueous suspensions were unstable
against sedimentation and they separated out into upper and bottom layers (U-
and B-layers, respectively). The dynamic light scattering technique revealed
that the addition of CTAB even at rather small concentration, $C_s=0.0164$ %wt
($0.03 CEC$), induced noticeable changes in the aging dynamics of U-layer, and
it was explained by equilibration of CTAB molecules that were initially
non-uniformly distributed between different Laponite particles. Accelerated
stability analysis by means of analytical centrifugation with rotor speed
${\omega}=500-4000$ rpm revealed three sedimentation regimes: continuous (I,
$C_s<0.14$ %wt), zone-like (II, $0.14<C_s<0.2$ %wt) and gel-like (III, $C_s
>0.2$ %wt). It was demonstrated that B-layer was "soft" in the zone-like
regime. The increase of ${\omega}$ resulted in its supplementary compressing
and the collapse of "soft" sediment above certain critical centrifugal
acceleration.


title:
Rutgers relation for the analysis of superfluid density in
  superconductors

abstract:
  It is shown that the thermodynamic Rutgers relation for the second order
phase transitions can be used for the analysis of the superfluid density data
irrespective of complexities of the Fermi surface, structure of the
superconducting gap, pairing strength, or scattering. The only limitation is
that critical fluctuations should be weak, so that the mean field theory of the
second order phase transitions is applicable. By using the Rutgers relation,
the zero temperature value of the London penetration depth, $\lambda(0)$, is
related to the specific heat jump $\Delta C$ and the slope of upper critical
field $dH_{c2}/dT$ at the transition temperature $T_c$, provided the data on
$\Delta\lambda=\lambda(T)-\lambda(0)$ are available in a broad temperature
domain. We then provide a new way of determination of $\lambda(0)$, the
quantity difficult to determine within many techniques.


title: Multi-loop open string amplitudes and their field theory limit

abstract:
  We study the field theory limit of multi-loop (super)string amplitudes, with
the aim of clarifying their relationship to Feynman diagrams describing the
dynamics of the massless states. We propose an explicit map between string
moduli around degeneration points and Schwinger proper-times characterizing
individual Feynman diagram topologies. This makes it possible to identify the
contribution of each light string state within the full string amplitude and to
extract the field theory Feynman rules selected by (covariantly quantized)
string theory. The connection between string and field theory amplitudes also
provides a concrete tool to clarify ambiguities related to total derivatives
over moduli space: in the superstring case, consistency with the field theory
results selects a specific prescription for integrating over supermoduli. In
this paper, as an example, we focus on open strings supported by parallel
D-branes, and we present two-loop examples drawn from bosonic and RNS string
theories, highlighting the common features between the two setups.


title:
Photon-atomic solitons in a Bose-Einstein condensate trapped in a soft
  optical lattice

abstract:
  We investigate the ground state (GS) of a collisionless Bose-Einstein
condensate (BEC) trapped in a soft one-dimensional optical lattice (OL), which
is formed by two counterpropagating optical beams perturbed by the BEC density
profile through the local-field effect (LFE). We show that LFE gives rise to an
envelope-deformation potential, a nonlocal potential resulting from the phase
deformation, and an effective self-interaction of the condensate. As a result,
stable photon-atomic lattice solitons, including an optical component, in the
form of the deformation of the soft OL, in a combination with a localized
matter-wave component, are generated in the blue-detuned setting, without any
direct interaction between atoms. These self-trapped modes, which realize the
system's GS, are essentially different from the gap solitons supported by the
interplay of the OL potential and collisional interactions between atoms. A
transition to tightly bound modes from loosely bound ones occurs with the
increase of the number of atoms in the BEC.


title:
Can MOND type hypotheses be tested in a free fall laboratory
  environment?

abstract:
  The extremely small accelerations of objects required for the the onset of
modified Newtonian dynamics, or MOND, makes testing the hypothesis in
conventional terrestrial laboratories virtually impossible. This is due to the
large background acceleration of Earth, which is transmitted to the
acceleration of test objects within an apparatus. We show however, that it may
be possible to test MOND-type hypotheses with experiments using a conventional
apparatus capable of tracking very small accelerations of its components, but
performed in locally inertial frames such as artificial satellites and other
freely falling laboratories. For example, experiments involving an optical
interferometer or a torsion balance in these laboratories would show nonlinear
dynamics, and displacement amplitudes larger than expected. These experiments
may also be able to test potential violations of the strong equivalence
principle by MOND and to distinguish between its two possible interpretations
(modified inertia and modified gravity).

categories: gr-qc astro-ph.CO astro-ph.GA hep-th physics.ins-det


title:
How complex climate networks complement eigen techniques for the
  statistical analysis of climatological data

abstract:
  Eigen techniques such as empirical orthogonal function (EOF) or coupled
pattern (CP) / maximum covariance analysis have been frequently used for
detecting patterns in multivariate climatological data sets. Recently,
statistical methods originating from the theory of complex networks have been
employed for the very same purpose of spatio-temporal analysis. This climate
network (CN) analysis is usually based on the same set of similarity matrices
as is used in classical EOF or CP analysis, e.g., the correlation matrix of a
single climatological field or the cross-correlation matrix between two
distinct climatological fields. In this study, formal relationships as well as
conceptual differences between both eigen and network approaches are derived
and illustrated using exemplary global precipitation, evaporation and surface
air temperature data sets. These results allow to pinpoint that CN analysis can
complement classical eigen techniques and provides additional information on
the higher-order structure of statistical interrelationships in climatological
data. Hence, CNs are a valuable supplement to the statistical toolbox of the
climatologist, particularly for making sense out of very large data sets such
as those generated by satellite observations and climate model intercomparison
exercises.


title: Stochastic gene expression with delay

abstract:
  The expression of genes usually follows a two-step procedure. First, a gene
(encoded in the genome) is transcribed resulting in a strand of (messenger)
RNA. Afterwards, the RNA is translated into protein. Classically, this gene
expression is modeled using a Markov jump process including activation and
deactivation of the gene, transcription and translation rates together with
degradation of RNA and protein. We extend this model by adding delays (with
arbitrary distributions) to transcription and translation. Such delays can
e.g.\ mean that RNA has to be transported to a different part of a cell before
translation can be initiated. Already in the classical model, production of RNA
and protein come in bursts by activation and deactivation of the gene,
resulting in a large variance of the number of RNA and proteins in equilibrium.
We derive precise formulas for this second-order structure with the model
including delay in equilibrium. As a general fact, the delay decreases the
variance of the number of RNA and proteins.


title: Rational solitons of wave resonant interaction models

abstract:
  Integrable models of resonant interaction of two or more waves in 1+1
dimensions are known to be of applicative interest in several areas. Here we
consider a system of three coupled wave equations which includes as special
cases the vector Nonlinear Schroedinger equations and the equations describing
the resonant interaction of three waves. The Darboux-Dressing construction of
soliton solutions is applied under the condition that the solutions have
rational, or mixed rational-exponential, dependence on coordinates. Our
algebraic construction relies on the use of nilpotent matrices and their Jordan
form. We systematically search for all bounded rational (mixed
rational-exponential) solutions and find, for the first time to our knowledge,
a broad family of such solutions of the three wave resonant interaction
equations.


title:
Interdiffusion of Ni-Al multilayers: a continuum and molecular dynamics
  study

abstract:
  Molecular dynamics simulation of Al/Ni multilayered foils reveals a range of
different reaction pathways depending on the temperature of the reaction. At
the highest temperatures Fickian interdiffusion dominates the intermixing
process. At intermediate temperatures Ni dissolution into the Al liquid becomes
the dominant mechanism for intermixing prior to formation of the B2
intermetallic phase. At lower temperatures the B2 intermetallic forms early in
the reaction process precluding both of these mechanisms. Interdiffusion and
dissolution activation energies as well as diffusion prefactors are extracted
from the simulations.


title: Cross sections from proton irradiation of thorium at 800 MeV

abstract:
  Nuclear formation cross sections are reported for 65 nuclides produced from
800-MeV proton irradiation of thorium foils. These data are useful as
benchmarks for computational predictions in the ongoing process of theoretical
code development and also to the design of spallation-based radioisotope
production currently being considered for multiple radiotherapeutic
pharmaceutical agents. Measured data are compared with the predictions of three
MCNP6 event generators and used to evaluate the potential for 800-MeV
productions of radioisotopes of interest for medical radiotherapy. In only a
few instances code predictions are discrepant from measured values by more than
a factor of two, demonstrating satisfactory predictive power across a large
mass range. Similarly, agreement between measurements presented here and those
previously reported is good, lending credibility to predictions of target
yields and radioimpurities for high-energy accelerator-produced radionuclides.


title: An Echo of Supernova 2008bk

abstract:
  I have discovered a prominent light echo around the low-luminosity Type
II-Plateau Supernova (SN) 2008bk in NGC 7793, seen in archival images obtained
with the Wide Field Channel of the Advanced Camera for Surveys on-board the
Hubble Space Telescope (HST). The echo is a partial ring, brighter to the north
and east than to the south and west. The analysis of the echo I present
suggests that it is due to the SN light pulse scattered by a sheet, or sheets,
of dust located ~15 pc from the SN. The composition of the dust is assumed to
be of standard Galactic diffuse interstellar grains. The visual extinction of
the dust responsible for the echo is A_V ~ 0.05 mag, in addition to the
extinction due to the Galactic foreground toward the host galaxy. That the SN
experienced much less overall extinction implies that it is seen through a less
dense portion of the interstellar medium in its environment. The late-time HST
photometry of SN 2008bk also clearly demonstrates that the progenitor star has
vanished.


title: Domain Types: Selecting Abstractions Based on Variable Usage

abstract:
  The success of software model checking depends on finding an appropriate
abstraction of the subject program. The choice of the abstract domain and the
analysis configuration is currently left to the user, who may not be familiar
with the tradeoffs and performance details of the available abstract domains.
We introduce the concept of domain types, which classify the program variables
into types that are more fine-grained than standard declared types, such as int
or long, in order to guide the selection of an appropriate abstract domain for
a model checker. Our implementation determines the domain type for each
variable in a pre-processing step, based on the variable usage in the program,
and then assigns each variable to an abstract domain. The model-checking
framework that we use supports to specify a separate analysis precision for
each abstract domain, such that we can freely configure the analysis. We
experimentally demonstrate a significant impact of the choice of the abstract
domain per variable. We consider one explicit (hash tables for integer values)
and one symbolic (binary decision diagrams) domain. The experiments are based
on standard verification tasks that are taken from recent competitions on
software verification. Each abstract domain has unique advantages in
representing the state space of variables of a certain domain type. Our
experiments show that software model checkers can be improved with a
domain-type guided combination of abstract domains.


title:
Understanding the origin of the [OI] low-velocity component from T Tauri
  stars

abstract:
  The formation time, masses, and location of planets are strongly impacted by
the physical mechanisms that disperse protoplanetary disks and the timescale
over which protoplanetary material is cleared out. Accretion of matter onto the
central star, protostellar winds/jets, magnetic disk winds, and
photoevaporative winds operate concurrently. Hence, disentangling their
relative contribution to disk dispersal requires identifying diagnostics that
trace different star-disk environments. Here, we analyze the low velocity
component (LVC) of the Oxygen optical forbidden lines, which is found to be
blueshifted by a few km/s with respect to the stellar velocity. We find that
the [OI] LVC profiles are different from those of [NeII] at 12.81\mu m and CO
at 4.7\mu m lines pointing to different origins for these gas lines. We report
a correlation between the luminosity of the [OI] LVC and the accretion
luminosity Lacc. We do not find any correlation with the X-ray luminosity,
while we find that the higher is the stellar FUV luminosity, the higher is the
luminosity of the [OI] LVC. In addition, we show that the [OI]6300\AA/5577\AA\
ratio is low (ranging between 1 and 8). These findings favor an origin of the
[OI] LVC in a region where OH is photodissociated by stellar FUV photons and
argue against thermal emission from an X-ray-heated layer. Detailed modeling of
two spectra with the highest S/N and resolution shows that there are two
components within the LVC: a broad, centrally peaked component that can be
attributed to gas arising in a warm disk surface in Keplerian rotation (with
FWHM between ~40 and ~60 km/s), and a narrow component (with FWHM ~10 km/s and
small blueshifts of ~2 km/s) that may arise in a cool (<1,000 K) molecular
wind.


title:
Positron on Neutron capture reaction, radiative corrections and neutron
  EDM

abstract:
  This paper presents an analysis of the positron capture by a neutron
reaction, which is just the inverse of the well-known neutrino capture by a
proton reaction. The effect of the QED radiative corrections is investigated.
In particular, the analysis considers the effects of treating the neutron as a
composite object that can have an electric dipole moment (nEDM). For the case
of unpolarized hadrons the effects of a nEDM appear to vanish.


title: Unique geodesics for Thompson's metric

abstract:
  In this paper a geometric characterization of the unique geodesics in
Thompson's metric spaces is presented. This characterization is used to prove a
variety of other geometric results. Firstly, it will be shown that there exists
a unique Thompson's metric geodesic connecting $x$ and $y$ in the cone of
positive self-adjoint elements in a unital $C^*$-algebra if, and only if, the
spectrum of $x^{-1/2}yx^{-1/2}$ is contained in $\{1/\beta,\beta\}$ for some
$\beta\geq 1$. A similar result will be established for symmetric cones.
Secondly, it will be shown that if $C^\circ$ is the interior of a
finite-dimensional closed cone $C$, then the Thompson's metric space
$(C^\circ,d_C)$ can be quasi-isometrically embedded into a finite-dimensional
normed space if, and only if, $C$ is a polyhedral cone. Moreover,
$(C^\circ,d_C)$ is isometric to a finite-dimensional normed space if, and only
if, $C$ is a simplicial cone. It will also be shown that if $C^\circ$ is the
interior of a strictly convex cone $C$ with $3\leq \dim C<\infty$, then every
Thompson's metric isometry is projectively linear.


title: Fast and accurate $G^1$ fitting of clothoid curves

abstract:
  A new effective solution to the problem of Hermite $G^1$ interpolation with a
clothoid curve is here proposed, that is a clothoid that interpolates two given
points in a plane with assigned unit tangent vectors. The interpolation problem
is a system of three nonlinear equations with multiple solutions which is
difficult to solve also numerically. Here the solution of this system is
reduced to the computation of the zeros of one single function in one variable.
The location of the zero associated to the relevant solution is studied
analytically: the interval containing the zero where the solution is proved to
exists and to be unique is provided. A simple guess function allows to find
that zero with very few iterations in all possible configurations.
  The computation of the clothoid curves and the solution algorithm call for
the evaluation of Fresnel related integrals. Such integrals need asymptotic
expansions near critical values to avoid loss of precision. This is necessary
when, for example, the solution of the interpolation problem is close to a
straight line or an arc of circle. A simple algorithm is presented for
efficient computation of the asymptotic expansion.
  The reduction of the problem to a single nonlinear function in one variable
and the use of asymptotic expansions make the present solution algorithm fast
and robust. In particular a comparison with algorithms present in literature
shows that the present algorithm requires less iterations. Moreover accuracy is
maintained in all possible configurations while other algorithms have a loss of
accuracy near the transition zones.


title: Inequality between size and angular momentum for bodies

abstract:
  A universal inequality that bounds the angular momentum of a body by the
square of its size is presented and heuristic physical arguments are given to
support it. We prove a version of this inequality, as consequence of Einstein
equations, for the case of rotating axially symmetric, constant density,
bodies. Finally, the physical relevance of this result is discussed.


title: Normalized Online Learning

abstract:
  We introduce online learning algorithms which are independent of feature
scales, proving regret bounds dependent on the ratio of scales existent in the
data rather than the absolute scale. This has several useful effects: there is
no need to pre-normalize data, the test-time and test-space complexity are
reduced, and the algorithms are more robust.


title:
Orthogonal Polynomials on the Unit Circle with Fibonacci Verblunsky
  Coefficients, II. Applications

abstract:
  We consider CMV matrices with Verblunsky coefficients determined in an
appropriate way by the Fibonacci sequence and present two applications of the
spectral theory of such matrices to problems in mathematical physics. In our
first application we estimate the spreading rates of quantum walks on the line
with time-independent coins following the Fibonacci sequence. The estimates we
obtain are explicit in terms of the parameters of the system. In our second
application, we establish a connection between the classical nearest neighbor
Ising model on the one-dimensional lattice in the complex magnetic field
regime, and CMV operators. In particular, given a sequence of nearest-neighbor
interaction couplings, we construct a sequence of Verblunsky coefficients, such
that the support of the Lee-Yang zeros of the partition function for the Ising
model in the thermodynamic limit coincides with the essential spectrum of the
CMV matrix with the constructed Verblunsky coefficients. Under certain
technical conditions, we also show that the zeros distribution measure
coincides with the density of states measure for the CMV matrix.


title: Controlling self-organized criticality in sandpile models

abstract:
  We introduce an external control to reduce the size of avalanches in some
sandpile models exhibiting self organized criticality. This rather intuitive
approach seems to be missing in the vast literature on such systems. The
control action, which amounts to triggering avalanches in sites that are near
to be come critical, reduces the probability of very large events, so that
energy dissipation occurs most locally. The control is applied to a directed
Abelian sandpile model driven by both uncorrelated and correlated deposition.
The latter is essential to design an efficient and simple control heuristic,
but has only small influence in the uncontrolled avalanche probability
distribution. The proposed control seeks a tradeoff between control cost and
large event risk. Preliminary results hint that the proposed control works also
for an undirected sandpile model.


title: Similar relatively hyperbolic actions of a group

abstract:
  Let a discrete group $G$ possess two convergence actions by homeomorphisms on
compacta $X$ and $Y$. Consider the following question: does there exist a
convergence action $G{\curvearrowright}Z$ on a compactum $Z$ and continuous
equivariant maps $X\leftarrow Z\to Y$? We call the space $Z$ (and action of $G$
on it) {\it pullback} space (action). In such general setting a negative answer
follows from a recent result of O. Baker and T. Riley [BR].
  Suppose, in addition, that the initial actions are relatively hyperbolic that
is they are non-parabolic and the induced action on the distinct pairs are
cocompact. Then the existence of the pullback space if $G$ is finitely
generated follows from \cite{Ge2}. The main result of the paper claims that the
pullback space exists if and only if the maximal parabolic subgroups of one of
the actions are dynamically quasiconvex for the other one.
  We provide an example of two relatively hyperbolic actions of the free group
$G$ of countable rank for which the pullback action does not exist.
  We study an analog of the notion of geodesic flow for relatively hyperbolic
groups. Further these results are used to prove the main theorem.


title: Active Sensing as Bayes-Optimal Sequential Decision Making

abstract:
  Sensory inference under conditions of uncertainty is a major problem in both
machine learning and computational neuroscience. An important but poorly
understood aspect of sensory processing is the role of active sensing. Here, we
present a Bayes-optimal inference and control framework for active sensing,
C-DAC (Context-Dependent Active Controller). Unlike previously proposed
algorithms that optimize abstract statistical objectives such as information
maximization (Infomax) [Butko & Movellan, 2010] or one-step look-ahead accuracy
[Najemnik & Geisler, 2005], our active sensing model directly minimizes a
combination of behavioral costs, such as temporal delay, response error, and
effort. We simulate these algorithms on a simple visual search task to
illustrate scenarios in which context-sensitivity is particularly beneficial
and optimization with respect to generic statistical objectives particularly
inadequate. Motivated by the geometric properties of the C-DAC policy, we
present both parametric and non-parametric approximations, which retain
context-sensitivity while significantly reducing computational complexity.
These approximations enable us to investigate the more complex problem
involving peripheral vision, and we notice that the difference between C-DAC
and statistical policies becomes even more evident in this scenario.


title: Simulating holographic correspondence in flexible graphene

abstract:
  In the spirit of the generalized holographic conjecture, we explore a
relationship between the bulk and boundary properties of non-interacting
massive Dirac fermions living on a flexible surface, such as a sheet of
graphene. We demonstrate that the boundary correlations can mimic those
normally found in the system of one-dimensional interacting fermions, a
specific form of such phantom interaction being determined by the bulk
geometry. This geometrical interpretation of the boundary interaction effects
offers a new insight into the possible origin of the more sophisticated types
of holographic correspondence and suggests potential ways of visualizing
'analogue holography' in the experimentally viable environments.


title: The hierarchy problem of the electroweak Standard Model revisited

abstract:
  A careful renormalization group analysis of the electroweak Standard Model,
considered as a low energy effective theory, reveals that there is no hierarchy
problem in the broken phase of the SM. In the broken phase a light Higgs turns
out to be natural as it appears self-protected and self-tuned by the
spontaneous symmetry breaking. It means that the scalar Higgs needs not be
protected by any extra symmetry, specifically super symmetry, in order not to
be much heavier than the other SM particles, which are protected by gauge- or
chiral-symmetry. Thus the existence of quadratic cutoff effects in the SM
cannot motivate the need for a super symmetric extensions of the SM, but in
contrast plays an important role in triggering the electroweak phase transition
at a scale about 10^{17} GeV and in shaping the Higgs potential in the early
universe to drive inflation as supported by observation. The impact on the
inflation profile of the quadratically enhanced bare Higgs mass term in the
unbroken phase is discussed in some detail. My analysis suggests that inflation
in the early universe is a direct consequence of the SM Higgs sector with its
quadratic enhancement of the bare Higgs mass term


title:
Strang-type preconditioners for solving fractional diffusion equations
  by boundary value methods

abstract:
  The finite difference scheme with the shifted Gr\"{u}nwarld formula is
employed to semi-discrete the fractional diffusion equations. This spatial
discretization can reduce to the large system of ordinary differential
equations (ODEs) with initial values. Recently, boundary value method (BVM) was
developed as a popular algorithm for solving large systems of ODEs. This method
requires the solutions of one or more nonsymmetric, large and sparse linear
systems. In this paper, the GMRES method with the block circulant
preconditioner is proposed for solving these linear systems. One of the main
results is that if an $A_{\nu_1,\nu_2}$-stable boundary value method is used
for an m-by-m system of ODEs, then the preconditioner is invertible and the
preconditioned matrix can be decomposed as I+L, where I is the identity matrix
and the rank of L is at most $2m(\nu_1+\nu_2)$. It means that when the GMRES
method is applied to solve the preconditioned linear systems, the method will
converge in at most $2m(\nu_1+\nu_2)+1$ iterations.Finally, extensive numerical
experiments are reported to illustrate the effectiveness of our methods for
solving the fractional diffusion equations.


title:
SZ observations with AMI of the hottest galaxy clusters detected in the
  XMM-Newton Cluster Survey

abstract:
  We have obtained deep SZ observations towards 15 of the apparently hottest
XMM Cluster Survey (XCS) clusters that can be observed with the Arcminute
Microkelvin Imager (AMI). We use a Bayesian analysis to quantify the
significance of our SZ detections. We detect the SZ effect at high significance
towards three of the clusters and at lower significance for a further two
clusters. Towards the remaining ten clusters, no clear SZ signal was measured.
We derive cluster parameters using the XCS mass estimates as a prior in our
Bayesian analysis. For all AMI-detected clusters, we calculate large-scale mass
and temperature estimates while for all undetected clusters we determine upper
limits on these parameters. We find that the large- scale mean temperatures
derived from our AMI SZ measurements (and the upper limits from null
detections) are substantially lower than the XCS-based core-temperature
estimates. For clusters detected in the SZ, the mean temperature is, on
average, a factor of 1.4 lower than temperatures from the XCS. For clusters
undetected in SZ, the average 68% upper limit on the mean temperature is a
factor of 1.9 below the XCS temperature.


title:
A joint analysis of AMI and CARMA observations of the recently
  discovered SZ galaxy cluster system AMI-CL J0300+2613

abstract:
  We present CARMA observations of a massive galaxy cluster discovered in the
AMI blind SZ survey. Without knowledge of the cluster redshift a Bayesian
analysis of the AMI, CARMA and joint AMI & CARMA uv-data is used to quantify
the detection significance and parameterise both the physical and observational
properties of the cluster whilst accounting for the statistics of primary CMB
anisotropies, receiver noise and radio sources. The joint analysis of the AMI &
CARMA uv-data was performed with two parametric physical cluster models: the
{\beta}-model; and the model described in Olamaie et al. 2012 with the pressure
profile fixed according to Arnaud et al. 2010. The cluster mass derived from
these different models is comparable but our Bayesian evidences indicate a
preference for the {\beta}-profile which we, therefore, use throughout our
analysis. From the CARMA data alone we obtain a Bayesian probability of
detection ratio of 12.8:1 when assuming that a cluster exists within our search
area; alternatively assuming that Jenkins et al. 2001 accurately predicts the
number of clusters as a function of mass and redshift, the Bayesian probability
of detection is 0.29:1. From the analysis of the AMI or AMI & CARMA data the
probability of detection ratio exceeds 4.5x10^3:1. Performing a joint analysis
of the AMI & CARMA data with a physical cluster model we derive the total mass
internal to r200 as MT,200 = 4.1x10^14Msun. Using a phenomenological
{\beta}-model to quantify the temperature decrement as a function of angular
distance we find a central SZ temperature decrement of 170{\mu}K in the AMI &
CARMA data. The SZ decrement in the CARMA data is weaker than expected and we
speculate that this is a consequence of the cluster morphology. In a
forthcoming study we will assess the impact of cluster morphology on the SZ
decrements that are observed with interferometers such as AMI and CARMA.


title: Controlling self-organized criticality in complex networks

abstract:
  A control scheme to reduce the size of avalanches of the Bak-Tang-Wiesenfeld
model on complex networks is proposed. Three network types are considered:
those proposed by Erd\H{o}s-Renyi, Goh-Kahng-Kim, and a real network
representing the main connections of the electrical power grid of the western
United States. The control scheme is based on the idea of triggering avalanches
in the highest degree nodes that are near to become critical. We show that this
strategy works in the sense that the dissipation of mass occurs most locally
avoiding larger avalanches. We also compare this strategy with a random
strategy where the nodes are chosen randomly. Although the random control has
some ability to reduce the probability of large avalanches, its performance is
much worse than the one based on the choice of the highest degree nodes.
Finally, we argue that the ability of the proposed control scheme is related to
its ability to reduce the concentration of mass on the network.


title: Two-stage Benchmarking as Applied to Small Area Estimation

abstract:
  There has been recent growth in small area estimation due to the need for
more precise estimation of small geographic areas, which has led to groups such
as the U.S. Census Bureau, Google, and the RAND corporation utilizing small
area estimation procedures. We develop novel two-stage benchmarking methodology
using a single weighted squared error loss function that combines the loss at
the unit level and the area level without any specific distributional
assumptions. We consider this loss while benchmarking the weighted means at
each level or both the weighted means and weighted variability at the unit
level. Multivariate extensions are immediate. We analyze the behavior of our
methods using a complex study from the National Health Interview Survey (NHIS)
from 2000, which estimates the proportion of people that do not have health
insurance for many domains of an Asian subpopulation. Finally, the methodology
is explored via simulated data under the proposed model. We ultimately conclude
that three proposed benchmarked Bayes estimators do not dominate each other,
leaving much exploration for future research.


title: On the Self-Recovery Phenomenon in the Process of Diffusion

abstract:
  We report a new phenomenon, called self-recovery, in the process of diffusion
in a region with boundary. Suppose that a diffusing quantity is uniformly
distributed initially and then gets excited by the change in the boundary
values over a time interval. When the boundary values return to their initial
values and stop varying afterwards, the value of a physical quantity related to
the diffusion automatically comes back to its original value. This
self-recovery phenomenon has been discovered and fairly well understood for
finite-dimensional mechanical systems with viscous damping. In this paper, we
show that it also occurs in the process of diffusion. Several examples are
provided from fluid flows, quasi-static electromagnetic fields and heat
conduction. In particular, our result in fluid flows provides a dynamic
explanation for the famous experiment by Sir G.I. Taylor with glycerine in an
annulus on kinematic reversibility of low-Reynolds-number flows.

categories: physics.flu-dyn math-ph math.DS math.MP physics.class-ph


title:
Dynamic Clustering via Asymptotics of the Dependent Dirichlet Process
  Mixture

abstract:
  This paper presents a novel algorithm, based upon the dependent Dirichlet
process mixture model (DDPMM), for clustering batch-sequential data containing
an unknown number of evolving clusters. The algorithm is derived via a
low-variance asymptotic analysis of the Gibbs sampling algorithm for the DDPMM,
and provides a hard clustering with convergence guarantees similar to those of
the k-means algorithm. Empirical results from a synthetic test with moving
Gaussian clusters and a test with real ADS-B aircraft trajectory data
demonstrate that the algorithm requires orders of magnitude less computational
time than contemporary probabilistic and hard clustering algorithms, while
providing higher accuracy on the examined datasets.


title:
Enhanced interface perpendicular magnetic anisotropy in Ta|CoFeB|MgO
  using nitrogen doped Ta underlayers

abstract:
  We show that the magnetic characteristics of Ta|CoFeB|MgO magnetic
heterostructures are strongly influenced by doping the Ta underlayer with
nitrogen. In particular, the saturation magnetization drops upon doping the Ta
underlayer, suggesting that the doped underlayer acts as a boron diffusion
barrier. In addition, the thickness of the magnetic dead layer decreases with
increasing nitrogen doping. Surprisingly, the interface magnetic anisotropy
increases to ~1.8 erg/cm2 when an optimum amount of nitrogen is introduced into
the Ta underlayer. These results show that nitrogen doped Ta serves as a good
underlayer for Spintronics applications including magnetic tunnel junctions and
domain wall devices.


title:
Forty two years counting spots: solar observations by D. E. Hadden
  during 1890-1931 revisited

abstract:
  We have recovered the sunspot observations made by David E. Hadden during
1890-1931 from Alta, Iowa. We have digitized the available data published by
Hadden in different astronomical journals. This data series have been analyzed
and compared with the standard sunspot number series. Moreover, we provide
additional information on two great sunspot groups, previously not described,
that originated two important extreme episodes of space weather on February
1892 and September 1898.


title: Nuclear Water Maser Emission in Centaurus A

abstract:
  We report the detection of a 22GHz water maser line in the nearest (D~3.8Mpc)
radio galaxy Centaurus A using the Australia Telescope Compact Array (ATCA).
The line is centered at a velocity of ~960kms-1, which is redshifted by about
400kms-1 from the systemic velocity. Such an offset, as well as the width of
~120kms-1, could be consistent with either a nuclear maser arising from an
accretion disk of the central supermassive black hole, or for a jet maser that
is emitted from the material that is shocked near the base of the jet in
Centaurus\,A. The best spatial resolution of our ATCA data constrains the
origin of the maser feature within <3pc from the supermassive black hole. The
maser exhibits a luminosity of ~1Lo, which classifies it as a kilomaser, and
appears to be variable on timescales of months. A kilomaser can also be emitted
by shocked gas in star forming regions. Given the small projected distance from
the core, the large offset from systemic velocity, as well as the smoothness of
the line feature, we conclude that a jet maser line emitted by shocked gas
around the base of the AGN is the most likely explanation. For this scenario we
can infer a minimum density of the radio jet of ~>10cm-3, which indicates
substantial mass entrainment of surrounding gas into the propagating jet
material.


title: Generalized Denoising Auto-Encoders as Generative Models

abstract:
  Recent work has shown how denoising and contractive autoencoders implicitly
capture the structure of the data-generating density, in the case where the
corruption noise is Gaussian, the reconstruction error is the squared error,
and the data is continuous-valued. This has led to various proposals for
sampling from this implicitly learned density function, using Langevin and
Metropolis-Hastings MCMC. However, it remained unclear how to connect the
training procedure of regularized auto-encoders to the implicit estimation of
the underlying data-generating distribution when the data are discrete, or
using other forms of corruption process and reconstruction errors. Another
issue is the mathematical justification which is only valid in the limit of
small corruption noise. We propose here a different attack on the problem,
which deals with all these issues: arbitrary (but noisy enough) corruption,
arbitrary reconstruction loss (seen as a log-likelihood), handling both
discrete and continuous-valued variables, and removing the bias due to
non-infinitesimal corruption noise (or non-infinitesimal contractive penalty).


title:
A QM/MM molecular dynamic simulation and vibrational spectroscopic study
  of 6-azaCytidine and cytidine

abstract:
  The conformational and vibrational properties of 6-azaCytidine (6-azaC) and
Cytidine (Cyt) have been studied in gas phase and aqueous environment. The two
most stable conformers of each molecule have been identified and investigated
in more details. The stability order of the two most stable conformers of both
molecules is changing going from gas phase to solution. The first solvation
shell of both molecules has been studied using QM/MM-MD (Quantum
Mechanics/Molecular Mechanics-Molecular Dynamic) simulations. The Raman
vibrational spectra in gas phase and aqueous solution have been simulated and
compared with the available experimental data. The two molecules exhibit
certain differences reflected in their spectra as a result of structural and
conformational differences.


title:
All-angle collimation of incident light in $\mathbf{\mu}$-near-zero
  metamaterials

abstract:
  We use the theory of inhomogeneous waves to study the transmission of light
in $\mu$-near-zero metamaterials. We find the effect of all-angle collimation
of incident light, which means that the vector of energy flow in a wave
transmitted to a $\mu$-near-zero metamaterial is perpendicular to the interface
for any incident angles if an incident wave is s-polarized. This effect is
similar to the all-angle collimation of incident light recently found through a
different theoretical framework in $\varepsilon$-near-zero metamaterials for a
p-polarized incident wave [S. Feng, Phys. Rev. Lett. 108, 193904 (2012)]. To
provide a specific example, we consider the transmission of light in a
negative-index metamaterial in the spectral region with a permeability
resonance, and show that all-angle collimation indeed takes place at the
wavelength for which the real part of permeability is vanishingly small.


title:
In Silico Design, Extended Molecular Dynamic Simulations and Binding
  Energy Calculations for a New Series of Dually Acting Inhibitors against EGFR
  and HER2

abstract:
  Starting from the lead structure we have identified in our previous works, we
are extending our insight understanding of its potential inhibitory effect
against both EGFR and HER2 receptors. Herein and using extended molecular
dynamic simulations and different scoring techniques, we are providing
plausible explanations for the observed inhibitory effect. Also, we are
comparing the binding mechanism in addition to the dynamics of binding with two
other approved inhibitors against EGFR (Lapatinib) and HER2 (SYR). Based on
this information, we are also designing and in silico screening new potential
inhibitors sharing the same scaffold of the lead structure. We have chosen the
best scoring inhibitor for additional in silico investigation against both the
wild-type and T790M mutant strain of EGFR. It seems that certain substitution
pattern guarantees the binding to the conserved water molecule commonly
observed with kinase crystal structures. Also, the new inhibitors seem to form
a stable interaction with the mutant strain as a direct consequence of their
enhanced ability to form additional interactions with binding site residues.


title:
Obtaining Laws of Thermodynamics for Ideal Gases using Elastic
  Collisions

abstract:
  The purpose of this note is to see to what extent ideal gas laws can be
obtained from simple Newtonian mechanics, specifically elastic collisions. We
present simple one-dimensional situations that seem to validate the laws. The
first section describes a numerical simulation that demonstrates the second law
of thermodynamics. The second section mathematically demonstrates the adiabatic
law of expansion of ideal gases.


title:
A dynamical programming approach for controlling the directed abelian
  Dhar-Ramaswamy model

abstract:
  A dynamical programming approach is used to deal with the problem of
controlling the directed abelian Dhar-Ramaswamy model on two-dimensional square
lattice. Two strategies are considered to obtain explicit results to this task.
First, the optimal solution of the problem is characterized by the solution of
the Bellman equation obtained by numerical algorithms. Second, the solution is
used as a benchmark to value how far from the optimum other heuristics that can
be applied to larger systems are. This approach is the first attempt on the
direction of schemes for controlling self-organized criticality that are based
on optimization principles that consider explicitly a tradeoff between the size
of the avalanches and the cost of intervention.


title: Domino Tatami Covering is NP-complete

abstract:
  A covering with dominoes of a rectilinear region is called \emph{tatami} if
no four dominoes meet at any point. We describe a reduction from planar 3SAT to
Domino Tatami Covering. As a consequence it is NP-complete to decide whether
there is a perfect matching of a graph that meets every 4-cycle, even if the
graph is restricted to be an induced subgraph of the grid-graph. The gadgets
used in the reduction were discovered with the help of a SAT-solver.


title:
Ultra-weak long-range interactions of solitons observed over
  astronomical distances

abstract:
  We report what we believe is the weakest interaction between solitons ever
observed. Our experiment involves temporal optical cavity solitons
recirculating in a coherently-driven passive optical fibre ring resonator. We
observe two solitons, separated by up to 8,000 times their width, changing
their temporal separation by a fraction of an attosecond per round-trip of the
100 m-long resonator, or equivalently 1/10,000 of the wavelength of the soliton
carrier wave per characteristic dispersive length. The interactions are so weak
that, at the speed of light, they require an effective propagation distance of
the order of an astronomical unit to fully develop, i.e. tens of millions of
kilometres. The interaction is mediated by transverse acoustic waves generated
in the optical fibre by the propagating solitons through electrostriction.


title: Maximum quantum violations of a class of Bell inequalities

abstract:
  We study a class of Bell inequalities and find their maximum quantum
violation. These inequalities involve n parties, two measurements per party,
with each measurement having two outcomes. The n=2 case corresponds to the CH
inequality. We use the method of Jordan bases to find the maximum quantum
violations. Results are found for the cases n=2 through n=7.


title:
Band nesting and the optical response of two-dimensional semiconducting
  transition metal dichalcogenides

abstract:
  We have studied the optical conductivity of two-dimensional (2D)
semiconducting transition metal dichalcogenides (STMDC) using ab-initio density
functional theory (DFT). We find that this class of materials presents large
optical response due to the phenomenon of band nesting. The tendency towards
band nesting is enhanced by the presence of van Hove singularities in the band
structure of these materials. Given that 2D crystals are atomically thin and
naturally transparent, our results show that it is possible to have strong
photon-electron interactions even in 2D


title: A characterisation of translation ovals in finite even order planes

abstract:
  In this article we consider a set C of points in PG(4,q), q even, satisfying
certain combinatorial properties with respect to the planes of PG(4,q). We show
that there is a regular spread in the hyperplane at infinity, such that in the
corresponding Bruck-Bose plane PG(2,q^2), the points corresponding to C form a
translation hyperoval, and conversely.


title: The tangent splash in $\PG(6,q)$

abstract:
  Let B be a subplane of PG(2,q^3) of order q that is tangent to $\ell_\infty$.
Then the tangent splash of B is defined to be the set of q^2+1 points of
$\ell_\infty$ that lie on a line of B. In the Bruck-Bose representation of
PG(2,q^3) in PG(6,q), we investigate the interaction between the ruled surface
corresponding to B and the planes corresponding to the tangent splash of B. We
then give a geometric construction of the unique order-$q$-subplane determined
by a given tangent splash and a fixed order-$q$-subline.


title:
A holomorphic transformation to a miniversal deformation under
  *congruence does not always exist

abstract:
  V.I. Arnold [Russian Math. Surveys 26(2) (1971) 29-43] constructed miniversal
deformations of square complex matrices under similarity. Reduction
transformations to them and also to miniversal deformations of matrix pencils
and matrices under congruence can be taken holomorphic. We prove that this is
not true for reduction transformations to miniversal deformations of matrices
under *congruence.


title:
Detecting cosmic string passage through the Earth by consequent global
  earthquake

abstract:
  Effects invoked by the passage of the cosmic string through the Earth are
investigated. The cosmic string induces global oscillations of the Earth whose
amplitude and acceleration both linearly depend on the string line density. For
the line density maximally allowed by the cosmic observations, the oscillations
are perceivable even to human beings and may cause serious damages to the
environment. Use of the sophisticated accelerograph enables us to detect the
string of a line density down to ten orders of magnitude smaller than the
cosmologically relevant value.


title: Technicolor with Scalar Doublet After the Discovery of Higgs Boson

abstract:
  The SM-like Higgs boson with mass of 125 GeV discovered at the LHC is subject
to a natural interpretation of electroweak symmetry breaking. As a successful
theory in offering this naturalness, technicolor with a scalar doublet and two
both $SU(3)_c$ and $SU(N_{TC})$ colored scalars, which is considered as a
low-energy effective theory, is proposed after the discovery of SM-like Higgs
boson. At present status, the model can be consistent with both the direct and
indirect experimental limits. In particular, the consistency with precision
electroweak measurements is realized by the colored scalars, which give rise to
a large {\it negative} contribution to $S$ parameter. It is also promising to
detect techni-pions and these colored scalars at the LHC.


title:
Impact of pi N --> pi pi N data on determining high-mass nucleon
  resonances

abstract:
  Motivated by an experimental proposal for the measurement of the pi N --> pi
pi N reactions at J-PARC, we examine a potential impact of the pi N --> pi pi N
cross section data on the determination of the resonance parameters of the
high-mass N* states. For this purpose, we make use of the ANL-Osaka dynamical
coupled-channels model, which has been developed recently by a combined
analysis of the unpolarized as well as polarized observables of pion- and
photon-induced pi N, eta N, K Lambda, and K Sigma production reactions off a
proton target. We present predictions for the pi N --> pi pi N total cross
sections and invariant mass distributions, and demonstrate that the pi N --> pi
pi N differential cross section data can indeed be a crucial source of
information for understanding N* --> pi Delta, rho N, sigma N --> pi pi N decay
of the high-mass N* states.


title: Small crater populations on Vesta

abstract:
  The NASA Dawn mission has extensively examined the surface of asteroid Vesta,
the second most massive body in the main belt. The high quality of the gathered
data provides us with an unique opportunity to determine the surface and
internal properties of one of the most important and intriguing main belt
asteroids (MBAs). In this paper, we focus on the size frequency distributions
(SFDs) of sub-kilometer impact craters observed at high spatial resolution on
several selected young terrains on Vesta. These small crater populations offer
an excellent opportunity to determine the nature of their asteroidal precursors
(namely MBAs) at sizes that are not directly observable from ground-based
telescopes (i.e., below ~100 m diameter). Moreover, unlike many other MBA
surfaces observed by spacecraft thus far, the young terrains examined had
crater spatial densities that were far from empirical saturation. Overall, we
find that the cumulative power-law index (slope) of small crater SFDs on Vesta
is fairly consistent with predictions derived from current collisional and
dynamical models down to a projectile size of ~10 m diameter (Bottke et al.,
2005a,b). The shape of the impactor SFD for small projectile sizes does not
appear to have changed over the last several billions of years, and an argument
can be made that the absolute number of small MBAs has remained roughly
constant (within a factor of 2) over the same time period. The apparent steady
state nature of the main belt population potentially provides us with a set of
intriguing constraints that can be used to glean insights into the physical
evolution of individual MBAs as well as the main belt as an ensemble.


title: CDT and the Search for a Theory of Quantum Gravity

abstract:
  Causal Dynamical Triangulations provide a non-perturbative regularization of
a theory of quantum gravity. We describe how this approach connects with the
asymptotic safety program and Ho\vrava-Lifshitz gravity theory, and present the
most recent results from computer simulations.


title:
Large eddy simulation of a muffler with the high-order spectral
  difference method

abstract:
  The combination of the high-order accurate spectral difference discretization
on unstructured grids with subgrid-scale modelling is investigated for large
eddy simulation of a muffler at Re = 4.64 10^4 and low Mach number. The
subgrid-scale stress tensor is modelled by the wall-adapting local
eddy-viscosity model with a cut-off length which is a decreasing function of
the order of accuracy of the scheme. Numerical results indicate that although
the high-order solver without subgrid-scale modelling is already able to
capture well the features of the flow, the coupling with the wall-adapting
local eddy-viscosity model improves the quality of the solution.


title:
Electronic transport of a large scale system studied by renormalized
  transfer matrix method: application to armchair graphene nanoribbons between
  quantum wires

abstract:
  Study on the electronic transport of a large scale two dimensional system by
the transfer matrix method (TMM) based on the Sch\"{o}rdinger equation suffers
from the numerical instability. To address this problem, we propose a
renormalized transfer matrix method (RTMM) by setting up a set of linear
equations from U times of multiplication of traditional transfer matrix
(U=N/S}with N and S being the atom number of length and the transfer step), and
smaller S is required for wider systems. Then we solve the above linear
equations by Gauss elimination method and further optimize to reduce the
computational complexity from O(U^3M^3) to O(UM^3), in which M is the atom
number of the width. Applying RTMM, we study transport properties of large
scale pure and long-range correlated disordered armchair graphene nanoribbon
(AGR) (carbon atoms up to 10^6 for pure case) between quantum wire contacts. As
for pure AGR, the conductance is superlinear with the Fermi energy and the
conductance is linear with the width while independent of the length, showing
characteristics of ballistic transport. As for disordered AGR with long-range
correlation, there is metal-insulator transition induced by the correlation
strength of disorder. It is straightforward to extend RTMM to investigate
transport in large scale system with irregular structure.


title: Fractional type Marcinkiewicz integral operators associated to surfaces

abstract:
  In this paper, we discuss the boundedness of the fractional type
Marcinkiewicz integral operators associated to surfaces, and extend a result
given by Chen, Fan and Ying in 2002. They showed that under certain conditions
the fractional type Marcinkiewicz integral operators are bounded from the
Triebel-Lizorkin spaces $\dot F_{pq}^{\alpha}({\mathbb R}^n)$ to $L^p({\mathbb
R}^n)$. Recently the second author, together with Xue and Yan, greatly weakened
their assumptions. In this paper, we extend their results to the case where the
operators are associated to the surfaces of the form $\{x=\phi(|y|)y/|y|\}
\subset {\mathbb R}^n \times ({\mathbb R}^n \setminus \{0\})$.
  To prove our result, we discuss a characterization of the homogeneous
Triebel-Lizorkin spaces in terms of lacunary sequences.


title:
Weak and strong type estimates for fractional integral operators on
  Morrey spaces in metric measure spaces

abstract:
  We discuss here a weak and strong type estimate for fractional integral
operators on Morrey spaces, where the underlying measure $\mu$ does not always
satisfy the doubling condition.


title:
Multiple fluxon analogues and dark solitons in linearly coupled
  Bose-Einstein condensates

abstract:
  Two effectively one-dimensional parallel coupled Bose-Einstein condensates in
the presence of external potentials are studied. The system is modelled by
linearly coupled Gross-Pitaevskii equations. In particular, the interactions of
grey-soliton-like solutions representing analogues of superconducting Josephson
fluxons as well as coupled dark solitons are discussed. A theoretical
approximation based on variational formulations to calculate the oscillation
frequency of the grey-soliton-like solution is derived and a qualitatively good
agreement is obtained.


title:
High Performance Lyot and PIAA Coronagraphy for Arbitrarily shaped
  Telescope Apertures

abstract:
  Two high performance coronagraphic approaches compatible with segmented and
obstructed telescope pupils are described. Both concepts use entrance pupil
amplitude apodization and a combined phase and amplitude focal plane mask to
achieve full coronagraphic extinction of an on-axis point source. While the
first concept, named Apodized Pupil Complex Mask Lyot Coronagraph (APCMLC),
relies on a transmission mask to perform the pupil apodization, the second
concept, named Phase-Induced Amplitude Apodization complex mask coronagraph
(PIAACMC), uses beam remapping for lossless apodization. Both concepts
theoretically offer complete coronagraphic extinction (infinite contrast) of a
point source in monochromatic light, with high throughput and sub-lambda/D
inner working angle, regardless of aperture shape. The PIAACMC offers nearly
100% throughput and approaches the fundamental coronagraph performance limit
imposed by first principles. The steps toward designing the coronagraphs for
arbitrary apertures are described for monochromatic light. Designs for the
APCMLC and the higher performance PIAACMC are shown for several monolith and
segmented apertures, such as the apertures of the Subaru Telescope, Giant
Magellan Telescope (GMT), Thirty Meter Telescope (TMT), the European Extremely
Large Telescope (E-ELT) and the Large Binocular Telescope (LBT). Performance in
broadband light is also quantified, suggesting that the monochromatic designs
are suitable for use in up to 20% wide spectral bands for ground-based
telescopes.


title:
Quantum phases of strongly interacting Rydberg atoms in triangular
  lattices

abstract:
  We present a theoretical study on the system of laser-driven strongly
interacting Rydberg atoms trapped in a two-dimensional triangular lattice, in
which the dipole-dipole interactions between Rydberg states result in exotic
quantum phases. By using the mean-field theory, we investigate the steady state
solutions and analyze their dynamical stabilities. We find that in the
strong-interaction limit, the dynamics of the system is chaotic and exhibits
random oscillations under appropriate laser detunings. Lyapunov exponent
criterion is introduced to confirm the existence of this chaotic behavior. In
addition, we present a full quantum calculation based on a six-atom model, and
find that the system exhibits some bi-antiferromagnetic properties in every
triangular cell when the one-photon detuning is exactly resonant or
blue-shifted.


title: Emergent Friedmann equation from the evolution of cosmic space revisited

abstract:
  Following the recent study on the emergent Friedmann equation from the
expansion of cosmic space for a flat universe, we apply this method to a
nonflat universe, and modify the evolution equation to lead to the Friedmann
equation. In order to maintain the same form with the original evolution
equation, we have to define the time-dependent Plank constant, which shows that
the spatial curvature of $k=0$ and $k=1$ is preferable to $k=-1$ since the
Plank constant of the nonflat open universe is divergent. Finally, we discuss
its physical consequences.


title: Equivariant principal bundles on nonsingular toric varieties

abstract:
  We give a classification of the equivariant principal $G$-bundles on a
nonsingular toric variety when $G$ is a closed Abelian subgroup of
$GL_k(\mathbb{C})$. We prove that any such bundle splits, that is, admits a
reduction of structure group to the intersection of $G$ with a torus. We give
an explicit parametrization of the isomorphism classes of such bundles for a
large family of $G$ when $X$ is complete.


title: Notes on the holographic Lifshitz theory

abstract:
  On the Lifshitz black brane geometry of an Einstein-Maxwell-dilaton gravity,
we holographically investigate electric DC conductivities and the role of
impurity in a non-relativistic Lifshitz medium with two different charge
carriers, impurity and Lifshitz matter. The conductivity carried by Lifshitz
matter is proportional to the square of temperature, while that carried by
impurity crucially depends on the bulk coupling parameter \g. For \g < -2,
impurity at high temperature can change the electric property of the Lifshitz
medium significantly so that the Lifshitz matter with impurity can show a
totally different electric property from the pure Lifshitz matter.


title: Sum theorems for maximally monotone operators of type (FPV)

abstract:
  The most important open problem in Monotone Operator Theory concerns the
maximal monotonicity of the sum of two maximally monotone operators provided
that the classical Rockafellar's constraint qualification holds.
  In this paper, we establish the maximal monotonicity of $A+B$ provided that
$A$ and $B$ are maximally monotone operators such that $\sta(\dom
A)\cap\inte\dom B\neq\varnothing$, and $A$ is of type (FPV). We show that when
also $\dom A$ is convex, the sum operator: $A+B$ is also of type (FPV). Our
result generalizes and unifies several recent sum theorems.


title: Coherent Flux Tunneling Through NbN Nanowires

abstract:
  We demonstrate evidence of coherent magnetic flux tunneling through
superconducting nanowires patterned in a thin highly disordered NbN film. The
phenomenon is revealed as a superposition of flux states in a fully metallic
superconducting loop with the nanowire acting as an effective tunnel barrier
for the magnetic flux, and reproducibly observed in different wires. The flux
superposition achieved in the fully metallic NbN rings proves the universality
of the phenomenon previously reported for InOx. We perform microwave
spectroscopy and study the tunneling amplitude as a function of the wire width,
compare the experimental results with theories, and estimate the parameters for
existing theoretical models.


title: Drawing the double circle on a grid of minimum size

abstract:
  In 1926, Jarn\'ik introduced the problem of drawing a convex $n$-gon with
vertices having integer coordinates. He constructed such a drawing in the grid
$[1,c\cdot n^{3/2}]^2$ for some constant $c>0$, and showed that this grid size
is optimal up to a constant factor. We consider the analogous problem for
drawing the double circle, and prove that it can be done within the same grid
size. Moreover, we give an O(n)-time algorithm to construct such a point set.


title: Entanglement entropy in higher derivative holography

abstract:
  We consider holographic entanglement entropy in higher derivative gravity
theories. Recently Lewkowycz and Maldacena arXiv:1304.4926 have provided a
method to derive the equations for the entangling surface from first
principles. We use this method to compute the entangling surface in four
derivative gravity. Certain interesting differences compared to the two
derivative case are pointed out. For Gauss-Bonnet gravity, we show that in the
regime where this method is applicable, the resulting equations coincide with
proposals in the literature as well as with what follows from considerations of
the stress tensor on the entangling surface. Finally we demonstrate that the
area functional in Gauss-Bonnet holography arises as a counterterm needed to
make the Euclidean action free of power law divergences.


title: Explosive Turbulent Magnetic Reconnection

abstract:
  We report simulation results for turbulent magnetic reconnection obtained
using a newly developed Reynolds-averaged magnetohydrodynamics model. We find
that the initial Harris current sheet develops in three ways, depending on the
strength of turbulence: laminar reconnection, turbulent reconnection, and
turbulent diffusion. The turbulent reconnection explosively converts the
magnetic field energy into both kinetic and thermal energy of plasmas, and
generates open fast reconnection jets. This fast turbulent reconnection is
achieved by the localization of turbulent diffusion. Additionally, localized
structure forms through the interaction of the mean field and turbulence.


title:
Simulations of Collisionless Perpendicular Shocks in Partially Ionized
  Plasmas

abstract:
  Perpendicular collisionless shocks propagating into partially ionized plasmas
are investigated by two-dimensional hybrid particle simulations. It is shown
that some neutral particles leak into the upstream region from the downstream
region, the leaking neutral particles become pickup ions in the upstream region
and modify the shock structure, the pickup ions are preferentially accelerated,
and plasma instabilities are excited by the pickup ions in the upstream and
downstream regions.


title: A Selection Criterion for Patterns in Reaction-Diffusion Systems

abstract:
  Alan Turing's work in Morphogenesis has received wide attention during the
past 60 years. The central idea behind his theory is that two chemically
interacting diffusible substances are able to generate stable spatial patterns,
provided certain conditions are met. Turing's proposal has already been
confirmed as a pattern formation mechanism in several chemical and biological
systems and, due to their wide applicability, there is a great deal of interest
in deciphering how to generate specific patterns under controlled conditions.
However, techniques allowing one to predict what kind of spatial structure will
emerge from Turing systems, as well as generalized reaction-diffusion systems,
remain unknown. Here, we consider a generalized reaction diffusion system on a
planar domain and provide an analytic criterion to determine whether spots or
stripes will be formed. It is motivated by the existence of an associated
energy function that allows bringing in the intuition provided by phase
transitions phenomena. This criterion is proved rigorously in some situations,
generalizing well known results for the scalar equation where the pattern
selection process can be understood in terms of a potential. In more complex
settings it is investigated numerically. Our criterion can be applied to
efficiently design Biotechnology and Developmental Biology experiments, or
simplify the analysis of hypothesized morphogenetic models.


title:
Statistical properties of chaotic microcavities in small and large
  opening cases

abstract:
  We study the crossover behavior of statistical properties of eigenvalues in a
chaotic microcavity with different refractive indices. The level spacing
distributions change from Wigner to Poisson distributions as the refractive
index of a microcavity decreases. We propose a non-hermitian matrix model with
random elements describing the spectral properties of the chaotic microcavity,
which exhibits the crossover behaviors as the opening strength increases.


title:
Reaction of Massive Clusters to Gas Expulsion - The cluster density
  dependence

abstract:
  The expulsion of the unconverted gas at the end of the star formation process
potentially leads to the expansion of the just formed stellar cluster and
membership loss. The degree of expansion and mass loss depends largely on the
star formation efficiency and scales with the mass and size of the stellar
group as long as stellar interactions can be neglected. We investigate under
which circumstances stellar interactions between cluster members become so
important that the fraction of bound stars after gas expulsion is significantly
altered. The Nbody6 code is used to simulate the cluster dynamics after gas
expulsion for different SFEs. Concentrating on the most massive clusters
observed in the Milky Way, we test to what extend the results depend on the
model, i.e. stellar mass distribution, stellar density profile etc., and the
cluster parameters, such as cluster density and size.We find that stellar
interactions are responsible for up to 20% mass loss in the most compact
massive clusters in the Milky Way, making ejections the prime mass loss process
in such systems. Even in the loosely bound OB associations stellar interactions
are responsible for at least ~5% mass loss. The main reason why the importance
of encounters for massive clusters has been largely overlooked is the often
used approach of a single-mass representation instead of a realistic
distribution for the stellar masses. The density-dependence of the
encounter-induced mass loss is shallower than expected because of the
increasing importance of few-body interactions in dense clusters compared to
sparse clusters where 2-body encounters dominate.