title: Bose Einstein condensation of the classical axion field in cosmology?

abstract:
  The axion is a motivated cold dark matter candidate, which it would be
interesting to distinguish from weakly interacting massive particles. Sikivie
has suggested that axions could behave differently during non-linear galaxy
evolution, if they form a Bose-Einstein condensate, and argues that
``gravitational thermalisation'' drives them to a Bose-Einstein condensate
during the radiation dominated era. Using classical equations of motion during
linear structure formation, we explore whether the gravitational interactions
of axions can generate entropy. At linear order in Newton's constant, we
interpret that the principle activities of gravity are to expand the Universe
and grow density fluctuations. To quantify the rate of entropy creation we use
the anisotropic stress to estimate a short dissipation scale for axions, which
does not confirm previous estimates of their gravitational thermalisation rate.


title:
V.A. Steklov and the Problem of Sharp (Exact) Constants in Inequalities
  of Mathematical Physics

abstract:
  The 150th anniversary of the birth of the outstanding Russian mathematician
Vladimir Andreevich Steklov falls on January 9, 2014. In this paper (it is a
part of survey to be published in January 2014), we describe advances in one of
several areas influenced by Steklov's work.


title:
Exploring Genome Characteristics and Sequence Quality Without a
  Reference

abstract:
  The de novo assembly of large, complex genomes is a significant challenge
with currently available DNA sequencing technology. While many de novo assembly
software packages are available, comparatively little attention has been paid
to assisting the user with the assembly. This paper addresses the practical
aspects of de novo assembly by introducing new ways to perform quality
assessment on a collection of DNA sequence reads. The software implementation
calculates per-base error rates, paired-end fragment size histograms and
coverage metrics in the absence of a reference genome. Additionally, the
software will estimate characteristics of the sequenced genome, such as repeat
content and heterozygosity, that are key determinants of assembly difficulty.
The software described is freely available and open source under the GNU Public
License.


title: The influence of Lorentz violation on UHE photon detection

abstract:
  We show that violation of the Lorentz symmetry in quantum electrodynamics can
suppress the rates of the interactions crucial for the formation of
photon-induced air showers, such as pair production on nuclei and in the
geomagnetic field. As a consequence, the allowed region in the space of
Lorentz-violating parameters will be seriously restricted if several photons
with energies $\gtrsim\,10^{19}\, {eV}$ are detected.


title:
An explicit example of Riemann surfaces with large bounds on corona
  solutions

abstract:
  By modifying Cole's example, we construct explicit Riemann surfaces with
large bounds on corona solutions in an elementary way.


title:
Proceedings Fourth International Symposium on Symbolic Computation in
  Software Science

abstract:
  Symbolic computation is the science of computing with symbolic objects
(terms, formulae, programs, algebraic objects, geometrical objects, etc).
Powerful symbolic algorithms have been developed during the past decades and
have played an influential role in theorem proving, automated reasoning,
software verification, model checking, rewriting, formalisation of mathematics,
network security, Groebner bases, characteristic sets, etc.
  The international Symposium on "Symbolic Computation in Software Science" is
the fourth in the SCSS workshop series. SCSS 2008 and 2010 took place at the
Research Institute for Symbolic Computation (RISC), Hagenberg, Austria, and,
SCSS 2009 took place in Gammarth, Tunisia. These symposium grew out of internal
workshops that bring together researchers from: a) SCORE (Symbolic Computation
Research Group) at the University of Tsukuba, Japan, b) Theorema Group at the
Research Institute for Symbolic Computation, Johannes Kepler University Linz,
Austria, c) SSFG (Software Science Foundation Group) at Kyoto University,
Japan, and d) Sup'Com (Higher School of Communication of Tunis) at the
University of Carthage, Tunisia.


title: A short proof of Hara and Nakai's theorem

abstract:
  We give a short proof of the following theorem of Hara and Nakai: for a
finitely bordered Riemann surface $R$, one can find an upper bound of the
corona constant of $R$ that depends only on the genus and the number of
boundary components of $R$.


title: Deep observations of O2 toward a low-mass protostar with Herschel-HIFI

abstract:
  According to traditional gas-phase chemical models, O2 should be abundant in
molecular clouds, but until recently, attempts to detect interstellar O2 line
emission with ground- and space-based observatories have failed. Following the
multi-line detections of O2 with low abundances in the Orion and rho Oph A
molecular clouds with Herschel, it is important to investigate other
environments, and we here quantify the O2 abundance near a solar-mass
protostar. Observations of O2, at 487 GHz toward a deeply embedded low-mass
Class 0 protostar, NGC 1333-IRAS 4A, are presented, using the HIFI instrument
on the Herschel Space Observatory. Complementary data of the chemically related
NO and CO molecules are obtained as well. The high spectral resolution data are
analysed using radiative transfer models to infer column densities and
abundances, and are tested directly against full gas-grain chemical models. The
deep HIFI spectrum fails to show O2 at the velocity of the dense protostellar
envelope, implying one of the lowest abundance upper limits of O2/H2 at
<6x10^-9 (3 sigma). However, a tentative (4.5 sigma) detection of O2 is seen at
the velocity of the surrounding NGC 1333 molecular cloud, shifted by 1 km/s
relative to the protostar. For the protostellar envelope, pure gas-phase models
and gas-grain chemical models require a long pre-collapse phase (~0.7-1x10^6
years), during which atomic and molecular oxygen are frozen out onto dust
grains and fully converted to H2O, to avoid overproduction of O2 in the dense
envelope. The same model also reproduces the limits on the chemically related
NO molecule. The tentative detection of O2 in the surrounding cloud is
consistent with a low-density PDR model with small changes in reaction rates.
The low O2 abundance in the collapsing envelope around a low-mass protostar
suggests that the gas and ice entering protoplanetary disks is very poor in O2.


title: Conformal and cp types of surfaces of class $\mathcal{S}$

abstract:
  In this paper we describe how to define the circle packing (cp) type(either
cp parabolic or cp hyperbolic) of a Riemann surface of class $\mathcal{S}$, and
study the relation between this type and the conformal type of the surface.


title:
Duality properties of strong isoperimetric inequalities on a planar
  graph and combinatorial curvatures

abstract:
  This paper is about hyperbolic properties on planar graphs. First, we study
the relations among various kinds of strong isoperimetric inequalities on
planar graphs and their duals. In particular, we show that a planar graph
satisfies a strong isoperimetric inequality if and only if its dual has the
same property, if the graph satisfies some minor regularity conditions and we
choose an appropriate notion of strong isoperimetric inequalities. Second, we
consider planar graphs where negative combinatorial curvatures dominate, and
use the outcomes of the first part to strengthen the results of Higuchi,
\.{Z}uk, and, especially, Woess. Finally, we study the relations between Gromov
hyperbolicity and strong isoperimetric inequalities on planar graphs, and give
a proof that a planar graph satisfying a proper kind of a strong isoperimetric
inequality must be Gromov hyperbolic if face degrees of the graph are bounded.
We also provide some examples to support our results.


title:
Production of minimally entangled typical thermal states with the
  Krylov-space approach

abstract:
  The minimally entangled typical thermal states algorithm is applied to
fermionic systems using the Krylov-space approach to evolve the system in
imaginary time. The convergence of local observables is studied in a
tight-binding system with a site-dependent potential. The temperature
dependence of the superconducting correlations of the attractive Hubbard model
is analyzed on chains, showing an exponential decay with distance and exponents
proportional to the temperature at low temperatures, as expected. In addition,
the non-local parity correlator is calculated at finite temperature. Other
possible applications of the minimally entangled typical thermal states
algorithm to fermionic systems are also discussed.


title: On the uniqueness of t->0+ quantum transition-state theory

abstract:
  It was shown recently that there exists a true quantum transition-state
theory (QTST) corresponding to the t->0+ limit of a (new form of) quantum
flux-side time-correlation function. Remarkably, this QTST is identical to
ring-polymer molecular dynamics (RPMD) TST. Here we provide evidence which
suggests very strongly that this QTST (= RPMD-TST) is unique, in the sense that
the t->0+ limit of any other flux-side time-correlation function gives either
non-positive-definite quantum statistics or zero. We introduce a generalized
flux-side time-correlation function which includes all other (known) flux-side
time-correlation functions as special limiting cases. We find that the only
non-zero t->0+ limit of this function that contains positive-definite quantum
statistics is RPMD-TST.


title: TPB-coated Light Guides for Liquid Argon TPC Light Detection Systems

abstract:
  Light detection systems in Liquid Argon Time Projection Chambers (LArTPCs)
require the detection of the 128 nm light produced during argon scintillation.
Most detectors use Tetraphenyl Butadiene (TPB) to shift the wavelength of the
light into a range visible to Photomultiplier Tubes (PMTs). These proceedings
summarize characterizations of light-guides coated with a matrix of TPB in UV
transmitting acrylic which are more compact than existing LArTPC light
collection systems.


title: A Rational Convex Program for Linear Arrow-Debreu Markets

abstract:
  We give a new, flow-type convex program describing equilibrium solutions to
linear Arrow-Debreu markets. Whereas convex formulations were previously known
[Nenakov, Primak 83; Jain 07; Cornet '89], our program exhibits several new
features. It gives a simple necessary and sufficient condition and a concise
proof of the existence and rationality of equilibria, settling an open question
raised by Vazirani. As a consequence we also obtain a simple new proof of
Mertens's result that the equilibrium prices form a convex polyhedral set.


title: Magnetically Controlled Circulation on Hot Extrasolar Planets

abstract:
  Through the process of thermal ionization, intense stellar irradiation
renders Hot Jupiter atmospheres electrically conductive. Simultaneously,
lateral variability in the irradiation drives the global circulation with peak
wind speeds of order ~ km/s. In turn, the interactions between the atmospheric
flows and the background magnetic field give rise to Lorentz forces that can
act to perturb the flow away from its purely hydrodynamical counterpart. Using
analytical theory and numerical simulations, here we show that significant
deviations away from axisymmetric circulation are unstable in presence of a
non-negligible axisymmetric magnetic field. Specifically, our results suggest
that dayside-to-nightside flows, often obtained within the context of
three-dimensional circulation models, only exist on objects with anomalously
low magnetic fields, while the majority of highly irradiated exoplanetary
atmospheres are entirely dominated by zonal jets.


title: Sharp constant in Riemannian L^p-Gagliardo-Nirenberg inequalities

abstract:
  Let (M,g) be a smooth compact Riemannian manifold of dimension n \geq 2, 1 <
p < n and 1 \leq q < r < p^\ast = \frac{np}{n-p} be real parameters. This paper
concerns to the validity of the optimal Gagliardo-Nirenberg inequality
  (\int_M |u|^r\; dv_g)^{\frac{\tau}{r \theta}} \leq (A_{opt} (\int_M |\nabla_g
u|^p\; dv_g)^{\frac{\tau}{p}} + B_{opt} (\int_M |u|^p\; dv_g)^{\frac{\tau}{p}})
(int_M |u|^q\; dv_g)^{\frac{\tau(1 - \theta)}{\theta q}} \; .
  This kind of inequality is studied in Chen and Sun (Nonlinear Analysis 72
(2010), pp. 3159-3172) where the authors established its validity when 2 < p <
r < p^\ast and (implicitly) \tau = 2. Here we solve the case p \geq r and
introduce one more parameter 1 \leq \tau \leq \min\{p,2\}. Moreover, we prove
the existence of extremal function for the optimal inequality above.


title:
Stabilization of Nonlinear Delay Systems Using Approximate Predictors
  and High-Gain Observers

abstract:
  We provide a solution to the heretofore open problem of stabilization of
systems with arbitrarily long delays at the input and output of a nonlinear
system using output feedback only. The solution is global, employs the
predictor approach over the period that combines the input and output delays,
addresses nonlinear systems with sampled measurements and with control applied
using a zero-order hold, and requires that the sampling/holding periods be
sufficiently short, though not necessarily constant. Our approach considers a
class of globally Lipschitz strict-feedback systems with disturbances and
employs an appropriately constructed successive approximation of the predictor
map, a high-gain sampled-data observer, and a linear stabilizing feedback for
the delay-free system. The obtained results guarantee robustness to
perturbations of the sampling schedule and different sampling and holding
periods are considered. The approach is specialized to linear systems, where
the predictor is available explicitly.


title:
Resource Efficient Gadgets for Compiling Adiabatic Quantum Optimization
  Problems

abstract:
  We develop a resource efficient method by which the ground-state of an
arbitrary k-local, optimization Hamiltonian can be encoded as the ground-state
of a (k-1)-local optimization Hamiltonian. This result is important because
adiabatic quantum algorithms are often most easily formulated using many-body
interactions but experimentally available interactions are generally 2-body. In
this context, the efficiency of a reduction gadget is measured by the number of
ancilla qubits required as well as the amount of control precision needed to
implement the resulting Hamiltonian. First, we optimize methods of applying
these gadgets to obtain 2-local Hamiltonians using the least possible number of
ancilla qubits. Next, we show a novel reduction gadget which minimizes control
precision and a heuristic which uses this gadget to compile 3-local problems
with a significant reduction in control precision. Finally, we present numerics
which indicate a substantial decrease in the resources required to implement
randomly generated, 3-body optimization Hamiltonians when compared to other
methods in the literature.


title:
Phase retrapping in a pointlike $\varphi$ Josephson junction: the
  Butterfly effect

abstract:
  We consider a $\varphi$ Josephson junction, which has a bistable zero-voltage
state with the stationary phases $\psi=\pm\varphi$. In the non-zero voltage
state the phase "moves" viscously along a tilted periodic double-well
potential. When the tilting is reduced quasistatically, the phase is retrapped
in one of the potential wells. We study the viscous phase dynamics to determine
in which well ($-\varphi$ or $+\varphi$) the phase is retrapped for a given
damping, when the junction returns from the finite-voltage state back to
zero-voltage state. In the limit of low damping the $\varphi$ Josephson
junction exhibits a butterfly effect --- extreme sensitivity of the destination
well on damping. This leads to an impossibility to predict the destination
well.

categories: cond-mat.supr-con math-ph math.MP nlin.CD


title:
A Review on Secured Money Transaction with Fingerprint Technique in ATM
  System

abstract:
  In the present day, the requirement of securing electronic cash flow system
are increasing significantly. Todays life is so busy that spending a valuable
second cost so much. In, such situation if money flow is possible swiftly by
just one swipe it would be a great relief. Biometric based authentication can
be a new approach to satisfy user needs by replacing password-based
authentication. Among all biometric techniques fingerprinting is the oldest and
secured methodology practised till date. In the proposed system user can
transact money by placing his/her thumb imprint on new proposed ATM card. This
new system will smoothen the transaction with security.


title:
The ultraluminous state revisited: fractional variability and spectral
  shape as diagnostics of super-Eddington accretion

abstract:
  Although we are nearing a consensus that most ULXs are stellar-mass black
holes in a super-Eddington state, little is yet established of the physics of
this accretion mode. Here, we use a combined X-ray spectral and timing analysis
of a sample of ULXs to investigate this new accretion regime. We suggest a
spectral classification scheme that separates ULXs into three classes: a
broadened disc class, and two-component hard and soft ultraluminous regimes. At
the lowest luminosities the ULX population is dominated by sources with
broadened disc spectra, whilst two component spectra are seen at higher
luminosities, suggestive of a distinction between ~ Eddington and
super-Eddington accretion modes. We find high levels of variability are limited
to ULXs with soft ultraluminous spectra, and a few broadened disc sources.
Furthermore, the variability is strongest at high energies, suggesting it
originates in the harder spectral component. These properties are consistent
with current models of super-Eddington emission, where a wind forms a funnel
around the central regions of the accretion flow. As the wind provides the soft
component this suggests that inclination is the key determinant in the observed
X-ray spectra, which is very strongly supported by the variability results if
this originates due to clumpy material at the edge of the wind intermittently
obscuring our line-of-sight to the central regions of the ULX. The pattern of
spectral variability with luminosity in two ULXs that straddle the hard/soft
ultraluminous regime boundary is consistent with the wind increasing at higher
accretion rates, and thus narrowing the opening angle of the funnel. Hence,
this work suggests that most ULXs can be explained as stellar-mass black holes
accreting at and above the Eddington limit, with their observed characteristics
dominated by two variables: accretion rate and inclination. (abridged)


title: Photometric and Thermal Cross-calibration of Solar EUV Instruments

abstract:
  We present an assessment of the accuracy of the calibration measurements and
atomic physics models that go into calculating the SDO/AIA response as a
function of wavelength and temperature. The wavelength response is tested by
convolving SDO/EVE and {\it Hinode}/EIS spectral data with the AIA effective
area functions and comparing the predictions with AIA observations. For most
channels, the AIA intensities summed over the disk agree with the corresponding
measurements derived from the current Version (V2) of the EVE data to within
the estimated 25% calibration error. This agreement indicates that the AIA
effective areas are generally stable in time. The AIA 304 \AA\ channel,
however, does show degradation by a factor of almost 3 from May 2010 through
September 2011, when the throughput apparently reached a minimum. We also find
some inconsistencies in the 335 \AA\ passband, possibly due to higher-order
contamination of the EVE data. The intensities in the AIA 193 \AA\ channel
agree to within the uncertainties with the corresponding measurements from EIS
full CCD observations. Analysis of high-resolution X-ray spectra of the
solar-like corona of Procyon, and of EVE spectra, allows us to investigate the
accuracy and completeness of the CHIANTI database in the AIA shorter wavelength
passbands. We find that in the 94 \AA\ channel, the spectral model
significantly underestimates the plasma emission owing to a multitude of
missing lines. We derive an empirical correction for the AIA temperature
responses by performing differential emission measure (DEM) inversion on a
broad set of EVE spectra and adjusting the AIA response functions so that the
count rates predicted by the full-disk DEMs match the observations.


title:
Joint estimation of causal effects from observational and intervention
  gene expression data

abstract:
  Background: Inference of gene regulatory networks from transcriptomic data
has been a wide research area in recent years. Proposed methods are mainly
based on the use of graphical Gaussian models for observational wild-type data
and provide undirected graphs that are not able to accurately highlight the
causal relationships among genes. In the present work, we seek to improve
estimation of causal effects among genes by jointly modeling observational
transcriptomic data with intervention data obtained by performing knock-outs or
knock-downs on a subset of genes. By examining the impact of such expression
perturbations on other genes, a more accurate reflection of regulatory
relationships may be obtained than through the use of wild-type data alone.
Results: Using the framework of Gaussian Bayesian networks, we propose a Markov
chain Monte Carlo algorithm with a Mallows model and an analytical likelihood
maximization to sample from the posterior distribution of causal node
orderings, and in turn, to estimate causal effects. The main advantage of the
proposed algorithm over previously proposed methods is that it has the
flexibility to accommodate any kind of intervention design, including partial
or multiple knock-out experiments. Methods were compared on simulated data as
well as data from the DREAM 2007 challenge. Conclusions: The simulation study
confirmed the impossibility of estimating causal orderings of genes with
observation data only. The proposed algorithm was found, in most cases, to
perform better than the previously proposed methods in terms of accuracy for
the estimation of causal effects. In addition, multiple knock-outs proved to
bring valuable additional information compared to single knock-outs. The choice
of optimal intervention design therefore appears to be a crucial aspect for
causal inference and an interesting challenge for future research.


title: Where are all the Sirius-Like Binary Systems?

abstract:
  Approximately 70 percent of the nearby white dwarfs appear to be single
stars, with the remainder being members of binary or multiple star systems. The
most numerous and most easily identifiable systems are those in which the main
sequence companion is an M star, since even if the systems are unresolved the
white dwarf either dominates or is at least competitive with the luminosity of
the companion at optical wavelengths. Harder to identify are systems where the
non-degenerate component has a spectral type earlier than M0 and the white
dwarf becomes the less luminous component. Taking Sirius as the prototype,
these latter systems are referred to here as Sirius-Like. There are currently
98 known Sirius-Like systems. Studies of the local white dwarf population
within 20 parsecs indicate that approximately 8 per cent of all white dwarfs
are members of Sirius-Like systems, yet beyond 20 parsecs the frequency of
known Sirius-Like systems declines to between 1 and 2 per cent, indicating that
many more of these systems remain to be found. Estimates are provided for the
local space density of Sirius- Like systems and their relative frequency among
both the local white dwarf population and the local population of A to K main
sequence stars. The great majority of currently unidentified Sirius-Like
systems will likely turn out to be closely separated and unresolved binaries.
Ways to observationally detect and study these systems are discussed.


title: Consistency of local renormalization group in d=3

abstract:
  We discuss Weyl anomaly and consistency conditions of local renormalization
group in d=1+2 dimensional quantum field theories. We give a classification of
the consistency conditions and ambiguities in most generality within the
power-counting renormalization scheme. They provide many non-trivial
constraints on possible forms of beta functions, anomalous dimensions and Weyl
anomaly of general d=1+2 dimensional quantum field theories. We perform modest
checks of our results in conformal perturbation theories, supersymmetric field
theories and holographic computations.


title: Optimistic Concurrency Control for Distributed Unsupervised Learning

abstract:
  Research on distributed machine learning algorithms has focused primarily on
one of two extremes - algorithms that obey strict concurrency constraints or
algorithms that obey few or no such constraints. We consider an intermediate
alternative in which algorithms optimistically assume that conflicts are
unlikely and if conflicts do arise a conflict-resolution protocol is invoked.
We view this "optimistic concurrency control" paradigm as particularly
appropriate for large-scale machine learning algorithms, particularly in the
unsupervised setting. We demonstrate our approach in three problem areas:
clustering, feature learning and online facility location. We evaluate our
methods via large-scale experiments in a cluster computing environment.


title: Interfacial Ferromagnetism in LaNiO3/CaMnO3 Superlattices

abstract:
  We observe interfacial ferromagnetism in superlattices of the paramagnetic
metal LaNiO3 and the antiferromagnetic insulator CaMnO3. LaNiO3 exhibits a
thickness dependent metal-insulator transition and we find the emergence of
ferromagnetism to be coincident with the conducting state of LaNiO3. That is,
only superlattices in which the LaNiO3 layers are metallic exhibit
ferromagnetism. Using several magnetic probes, we have determined that the
ferromagnetism arises in a single unit cell of CaMnO3 at the interface.
Together these results suggest that ferromagnetism can be attributed to a
double exchange interaction among Mn ions mediated by the adjacent itinerant
metal.


title: Secondary Emission Calorimetry: Fast and Radiation-Hard

abstract:
  A novel calorimeter sensor for electron, photon and hadron energy measurement
based on Secondary Emission(SE) to measure ionization is described, using
sheet-dynodes directly as the active detection medium; the shower particles in
an SE calorimeter cause direct secondary emission from dynode arrays comprising
the sampling or absorbing medium. Data is presented on prototype tests and
Monte Carlo simulations. This sensor can be made radiation hard at GigaRad
levels, is easily transversely segmentable at the mm scale, and in a
calorimeter has energy signal rise-times and integration comparable to or
better than plastic scintillation/PMT calorimeters. Applications are mainly in
the energy and intensity frontiers.


title:
Graphics Processing Unit acceleration of the Random Phase Approximation
  in the projector augmented wave method

abstract:
  The Random Phase Approximation (RPA) for correlation energy in the grid-based
projector augmented wave (gpaw) code is accelerated by porting to the Graphics
Processing Unit (GPU) architecture. The acceleration is achieved by grouping
independent vectors/matrices and transforming the implementation from being
memory bound to being computation/latency bound. With this approach, both the
CPU and GPU implementations have been enhanced. We tested the GPU
implementation on a few representative systems: molecules (O2), bulk solids
(Li2O and MoO3) and molecules adsorbed on metal surfaces (N2/Ru(0001) and
CO/Ni(111)). Improvements from 10+ to 40+ have been achieved (8-GPUs versus
8-CPUs). A realistic RPA calculation for CO/Ni(111) surface can be finished in
5.5 h using 8 GPUs. It is thus promising to employ non-self-consistent RPA for
routine surface chemistry simulations.


title: Direct observation of band bending in topological insulator Bi2Se3

abstract:
  The surface band bending tunes considerably the surface band structures and
transport properties in topological insulators. We present a direct measurement
of the band bending on the Bi2Se3 by using the bulk sensitive angular-resolved
hard x-ray photospectroscopy (HAXPES). We tracked the depth dependence of the
energy shift of Bi and Se core states. We estimate that the band bending
extends up to about 20 nm into the bulk with an amplitude of 0.23--0.26 eV,
consistent with profiles previously deduced from the binding energies of
surface states in this material.


title:
Weak topological insulators induced by the inter-layer coupling: A
  first-principles study of stacked Bi2TeI

abstract:
  Based on first-principles calculations, we predict Bi2TeI, a stoichiometric
compound synthesized, to be a weak topological insulator (TI) in layered
subvalent bismuth telluroiodides. Within a bulk energy gap of 80 meV, two
Dirac-cone-like topological surface states exist on the side surface
perpendicular to BiTeI layer plane. These Dirac cones are relatively isotropic
due to the strong inter-layer coupling, distinguished from those of previously
reported weak TI candidates. Moreover, with chemically stable cladding layers,
the BiTeI-Bi2-BiTeI sandwiched structure is a robust quantum spin Hall system,
which can be obtained by simply cleaving the bulk Bi2TeI.


title:
Ratner's property for special flows over irrational rotations under
  functions of bounded variation. II

abstract:
  We consider special flows over the rotation on the circle by an irrational
$\alpha$ under roof functions of bounded variation. The roof functions, in the
Lebesgue decomposition, are assumed to have a continuous singular part coming
from a quasi-similar Cantor set (including the Devil's staircase case).
Moreover, a finite number of discontinuities is allowed. Assuming that $\alpha$
has bounded partial quotients, we prove that all such flows are weakly mixing
and enjoy weak Ratner's property. Moreover, we provide a sufficient condition
for the roof function to obtain a stability of the cocycle Ratner's property
for the resulting special flow.


title:
Landau level transitions indoped graphene in a time dependent magnetic
  field

abstract:
  The aim of this work is to describe the Landau levels transitions of Bloch
electrons in doped graphene with an arbitrary time dependent magnetic field in
the long wavelength approximation. In particular, transitions from the m Landau
level to the m + 1 and m + 2 Landau levels are studied using time-dependent
perturbation theory. Time intervals are computed in which transition
probabilities tend to zero at low order in the coupling constant. In
particular, Landau level transitions are studied in the case of Bloch electrons
travelling in the direction of the applied magnetic force and the results are
compared with classical and revival periods of electrical current in graphene.
Finally, current probabilities are computed for the n = 0 and n = 1 Landau
levels showing expected oscillating behavior with modified cyclotron frequency.


title: Extracting Connected Concepts from Biomedical Texts using Fog Index

abstract:
  In this paper, we establish Fog Index (FI) as a text filter to locate the
sentences in texts that contain connected biomedical concepts of interest. To
do so, we have used 24 random papers each containing four pairs of connected
concepts. For each pair, we categorize sentences based on whether they contain
both, any or none of the concepts. We then use FI to measure difficulty of the
sentences of each category and find that sentences containing both of the
concepts have low readability. We rank sentences of a text according to their
FI and select 30 percent of the most difficult sentences. We use an association
matrix to track the most frequent pairs of concepts in them. This matrix
reports that the first filter produces some pairs that hold almost no
connections. To remove these unwanted pairs, we use the Equally Weighted
Harmonic Mean of their Positive Predictive Value (PPV) and Sensitivity as a
second filter. Experimental results demonstrate the effectiveness of our
method.


title: Strong Stability Preserving Multistep Runge-Kutta Methods

abstract:
  High-order spatial discretizations with strong stability properties (such as
monotonicity) are desirable for the solution of hyperbolic PDEs. Methods may be
compared in terms of the strong stability preserving (SSP) time-step. We prove
an upper bound on the SSP coefficient of explicit multistep Runge--Kutta
methods of order two and above. Order conditions and monotonicity conditions
for such methods are worked out in terms of the method coefficients. Numerical
optimization is used to find optimized explicit methods of up to five steps,
eight stages, and tenth order. These methods are tested on the advection and
Buckley-Leverett equations, and the results for the observed total variation
diminishing and positivity preserving time-step are presented.


title: The dipole model Monte Carlo generator Sartre 1

abstract:
  We present the Monte Carlo generator Sartre for simulating diffractive
exclusive vector meson production and DVCS in electron-proton, electron-ion,
and hadron-hadron collisions.


title: Extracting Information-rich Part of Texts using Text Denoising

abstract:
  The aim of this paper is to report on a novel text reduction technique,
called Text Denoising, that highlights information-rich content when processing
a large volume of text data, especially from the biomedical domain. The core
feature of the technique, the text readability index, embodies the hypothesis
that complex text is more information-rich than the rest. When applied on tasks
like biomedical relation bearing text extraction, keyphrase indexing and
extracting sentences describing protein interactions, it is evident that the
reduced set of text produced by text denoising is more information-rich than
the rest.


title:
Optimising Spectroscopic and Photometric Galaxy Surveys: Efficient
  Target Selection and Survey Strategy

abstract:
  The next generation of spectroscopic surveys will have a wealth of
photometric data available for use in target selection. Selecting the best
targets is likely to be one of the most important hurdles in making these
spectroscopic campaigns as successful as possible. Our ability to measure dark
energy depends strongly on the types of targets that we are able to select with
a given photometric data set. We show in this paper that we will be able to
successfully select the targets needed for the next generation of spectroscopic
surveys. We also investigate the details of this selection, including
optimisation of instrument design and survey strategy in order to measure dark
energy. We use color-color selection as well as neural networks to select the
best possible emission line galaxies and luminous red galaxies for a
cosmological survey. Using the Fisher matrix formalism we forecast the
efficiency of each target selection scenario. We show how the dark energy
figures of merit change in each target selection regime as a function of target
type, survey time, survey density and other survey parameters. We outline the
optimal target selection scenarios and survey strategy choices which will be
available to the next generation of spectroscopic surveys.


title:
Optimising Spectroscopic and Photometric Galaxy Surveys: Same-sky
  Benefits for Dark Energy and Modified Gravity

abstract:
  The combination of multiple cosmological probes can produce measurements of
cosmological parameters much more stringent than those possible with any
individual probe. We examine the combination of two highly correlated probes of
late-time structure growth: (i) weak gravitational lensing from a survey with
photometric redshifts and (ii) galaxy clustering and redshift space distortions
from a survey with spectroscopic redshifts. We choose generic survey designs so
that our results are applicable to a range of current and future photometric
redshift (e.g. KiDS, DES, HSC, Euclid) and spectroscopic redshift (e.g. DESI,
4MOST, Sumire) surveys. Combining the surveys greatly improves their power to
measure both dark energy and modified gravity. An independent, non-overlapping
combination sees a dark energy figure of merit more than 4 times larger than
that produced by either survey alone. The powerful synergies between the
surveys are strongest for modified gravity, where their constraints are
orthogonal, producing a non-overlapping joint figure of merit nearly 2 orders
of magnitude larger than either alone. Our projected angular power spectrum
formalism makes it easy to model the cross-correlation observable when the
surveys overlap on the sky, producing a joint data vector and full covariance
matrix. We calculate a same-sky improvement factor, from the inclusion of these
cross-correlations, relative to non-overlapping surveys. We find nearly a
factor of 4 for dark energy and more than a factor of 2 for modified gravity.
The exact forecast figures of merit and same-sky benefits can be radically
affected by a range of forecasts assumption, which we explore methodically in a
sensitivity analysis. We show that that our fiducial assumptions produce robust
results which give a good average picture of the science return from combining
photometric and spectroscopic surveys.


title:
Magnetic Susceptibility of Strongly Interacting Matter across the
  Deconfinement Transition

abstract:
  We propose a method to determine the total magnetic susceptibility of
strongly interacting matter by lattice QCD simulations, and present first
numerical results for the theory with two light flavors, which suggest a weak
magnetic activity in the confined phase and the emergence of strong
paramagnetism in the deconfined, Quark-Gluon Plasma phase.


title:
Predictions Wrong Again on Dead Zone Area -- Gulf of Mexico Gaining
  Resistance to Nutrient Loading

abstract:
  Mississippi River nutrient loads and water stratification on the
Louisiana-Texas shelf contribute to an annually recurring, short-lived hypoxic
bottom layer in areas of the northern Gulf of Mexico comprising less than 2% of
the total Gulf of Mexico bottom area. This paper observes that the NOAA and
LUMCON have now published errant predictions of possible record size areas of
temporary bottom water hypoxia ("dead zones") three times since 2005, in 2008,
2011, and 2013 and that the LUMCON predictions of the area of hypoxic bottom
water average 31% higher than the actual measured hypoxic areas from 2006 to
2014. These systematically high predictions depend on the assumption that the
susceptibility of the Gulf of Mexico to forming hypoxic areas in response to
nutrient loading has been relatively constant since 2001, though the
susceptibility has been occasionally adjusted upward in different models. It
has been previously suggested that tropical storms in a given year that occur
on the Louisiana-Texas shelf between the peak nutrient loading in spring and
formation of the hypoxic zone in summer can mitigate the size of the hypoxic
zone that year through mixing of stratified well oxygenated lighter and warmer
surface layers and oxygen depleted heavier and cooler bottom layers. This paper
suggests several reasons why the Louisiana-Texas shelf may be systematically
growing less susceptible to a given level of nutrient loading over time so that
predictions based on the measured area of temporary bottom water hypoxia prior
to 2006 tend to be too big in recent years.


title:
Biaxiality in the asymptotic analysis of a 2-D Landau-de Gennes model
  for liquid crystals

abstract:
  We consider the Landau-de Gennes variational problem on a bound\-ed, two
dimensional domain, subject to Dirichlet smooth boundary conditions. We prove
that minimizers are maximally biaxial near the singularities, that is, their
biaxiality parameter reaches the maximum value $1$. Moreover, we discuss the
convergence of minimizers in the vanishing elastic constant limit. Our
asymptotic analysis is performed in a general setting, which recovers the
Landau-de Gennes problem as a specific case.


title:
Formality of Kapranov's brackets in K\"ahler geometry via pre-Lie
  deformation theory

abstract:
  We recover some recent results by Dotsenko, Shadrin and Vallette on the
Deligne groupoid of a pre-Lie algebra, showing that they follow naturally by a
pre-Lie variant of the PBW Theorem. As an application, we show that Kapranov's
$L_\infty$ algebra structure on the Dolbeault complex of a K\"ahler manifold is
homotopy abelian and independent on the choice of K\"ahler metric up to an
$L_\infty$ isomorphism, by making the trivializing homotopy and the $L_\infty$
isomorphism explicit.


title: On the Change in Archivability of Websites Over Time

abstract:
  As web technologies evolve, web archivists work to keep up so that our
digital history is preserved. Recent advances in web technologies have
introduced client-side executed scripts that load data without a referential
identifier or that require user interaction (e.g., content loading when the
page has scrolled). These advances have made automating methods for capturing
web pages more difficult. Because of the evolving schemes of publishing web
pages along with the progressive capability of web preservation tools, the
archivability of pages on the web has varied over time. In this paper we show
that the archivability of a web page can be deduced from the type of page being
archived, which aligns with that page's accessibility in respect to dynamic
content. We show concrete examples of when these technologies were introduced
by referencing mementos of pages that have persisted through a long evolution
of available technologies. Identifying these reasons for the inability of these
web pages to be archived in the past in respect to accessibility serves as a
guide for ensuring that content that has longevity is published using good
practice methods that make it available for preservation.


title: Semiclassics for particles with spin via a Wigner-Weyl-type calculus

abstract:
  We show how to relate the full quantum dynamics of a spin-1/2 particle on R^d
to a classical Hamiltonian dynamics on the enlarged phase space R^d x S^2 up to
errors of second order in the semiclassical parameter. This is done via an
Egorov-type theorem for normal Wigner-Weyl calculus for R^d [Lei10,Fol89]
combined with the Stratonovich-Weyl calculus for SU(2) [VGB89]. For a specific
class of Hamiltonians, including the Rabi- and Jaynes-Cummings model, we prove
an Egorov theorem for times much longer than the semiclassical time scale. We
illustrate the approach for a simple model of the Stern-Gerlach experiment.


title:
Superconducting analogue of the parafermion fractional quantum Hall
  states

abstract:
  Read and Rezayi $Z_k$ parafermion wavefunctions describe
$\nu=2+\frac{k}{kM+2}$ fractional quantum Hall (FQH) states. These states
support non-Abelian excitations from which protected quantum gates can be
designed. However, there is no experimental evidence for these non-Abelian
anyons to date. In this paper, we study the $\nu=2/k$ FQH-superconductor
heterostructure and find the superconducting analogue of the $Z_k$ parafermion
FQH state. Our main tool is the mapping of the FQH into coupled one-dimensional
(1D) chains each with a pair of counter-propagating modes. We show that by
inducing intra-chain pairing and charge preserving backscattering with
identical couplings, the 1D chains flow into gapless $Z_{k}$ parafermions when
$k< 4$. By studying the effect of inter-chain coupling, we show that every
parafermion mode becomes massive except for the two outermost ones. Thus, we
achieve a fractional topological superconductor whose chiral edge state is
described by a $Z_k$ parafermion conformal field theory. For instance, we find
that a $\nu=2/3$ FQH in proximity to a superconductor produces a $Z_3$
parafermion superconducting state. This state is topologically
indistinguishable from the non-Abelian part of the $\nu=12/5$ Read-Rezay state.
Both of these systems can host Fibonacci anyons capable of performing universal
quantum computation through braiding operations.


title: Upper Limits From Five Years of VERITAS Blazar Observations

abstract:
  The VERITAS array of Cherenkov telescopes was used to observe ~130 blazars
from 2007 to 2012. Of these, 25 were detected as very-high-energy (VHE; E > 100
GeV) sources. We present here the results of the analysis of 65 VERITAS
non-detected blazars, including upper limits on their VHE flux. Results from a
stacked analysis of the entire data set and of smaller sub-sets (defined as a
function of the redshift and the blazar class) are presented and discussed.


title:
A Solution to the Edge-Balanced Index Set Problem for Complete Odd
  Bipartite Graphs

abstract:
  In 2009, Kong, Wang, and Lee began work on the problem of finding the
edge-balanced index sets (EBI) of complete bipartite graphs K_{m,n} by solving
the cases where n = 1, 2, 3, 4, and 5, and also the case where m = n. In 2011,
Krop and Sikes expanded upon that work by finding EBI(K_{m,m-2a}) for odd m > 5
and 1 <= a <= (m-3)/4. In this paper, we provide a general solution to the
edge-balanced index set problem for all complete odd bipartite graphs, thereby
concluding the problem for this case.


title:
Deep Chandra Observations of Abell 2199: the Interplay between
  Merger-Induced Gas Motions and Nuclear Outbursts in a Cool Core Cluster

abstract:
  We present new Chandra observations of Abell 2199 that show evidence of gas
sloshing due to a minor merger, as well as impacts of the radio source, 3C 338,
hosted by the central galaxy, NGC 6166, on the intracluster gas. The new data
are consistent with previous evidence of a Mach 1.46 shock 100" from the
cluster center, although there is still no convincing evidence for the expected
temperature jump. Other interpretations of this feature are possible, but none
is fully satisfactory. Large scale asymmetries, including enhanced X-ray
emission 200" southwest of the cluster center and a plume of low entropy,
enriched gas reaching 50" to the north of the center, are signatures of gas
sloshing induced by core passage of a merging subcluster about 400 Myr ago. An
association between the unusual radio ridge and low entropy gas are consistent
with this feature being the remnant of a former radio jet that was swept away
from the AGN by gas sloshing. A large discrepancy between the energy required
to produce the 100" shock and the enthalpy of the outer radio lobes of 3C 338
suggests that the lobes were formed by a more recent, less powerful radio
outburst. Lack of evidence for shocks in the central 10" indicates that the
power of the jet now is some two orders of magnitude smaller than when the 100"
shock was formed.


title: A general abstract approach to approximation properties in Banach spaces

abstract:
  We propose a unifying approach to many approximation properties studied in
the literature from the 1930s up to our days. To do so, we say that a Banach
space E has the (I,J,{\tau})-approximation property if E-valued operators
belonging to the operator ideal I can be approximated, with respect to the
topology {\tau}, by operators belonging to the operator ideal J. Restricting
{\tau} to a class of linear topologies, which we call ideal topologies, this
concept recovers many classical/recent approximation properties as particular
instances and several important known results are particular cases of more
general results that are valid in this abstract framework.


title: Euclidean algorithm and polynomial equations after Labatie

abstract:
  We recall Labatie's effective method of solving polynomial equations with two
unknowns by using the Euclidean algorithm.


title:
Noise and information transmission in promoters with multiple internal
  states

abstract:
  Based on the measurements of noise in gene expression performed during the
last decade, it has become customary to think of gene regulation in terms of a
two-state model, where the promoter of a gene can stochastically switch between
an ON and an OFF state. As experiments are becoming increasingly precise and
the deviations from the two-state model start to be observable, we ask about
the experimental signatures of complex multi-state promoters, as well as the
functional consequences of this additional complexity. In detail, we (i) extend
the calculations for noise in gene expression to promoters described by state
transition diagrams with multiple states, (ii) systematically compute the
experimentally accessible noise characteristics for these complex promoters,
and (iii) use information theory to evaluate the channel capacities of complex
promoter architectures and compare them to the baseline provided by the
two-state model. We find that adding internal states to the promoter
generically decreases channel capacity, except in certain cases, three of which
(cooperativity, dual-role regulation, promoter cycling) we analyze in detail.


title: Non-Simplified SUSY: stau-Coannihilation at LHC and ILC

abstract:
  Simplified models have become a widely used and important tool to cover the
more diverse phenomenology beyond constrained SUSY models. However, they come
with a substantial number of caveats themselves, and great care needs to be
taken when drawing conclusions from limits based on the simplified approach. To
illustrate this issue with a concrete example, we examine the applicability of
simplified model results to a series of full SUSY model points which all
feature a small stau-LSP mass difference, and are compatible with electroweak
and flavor precision observables as well as current LHC results. Various
channels have been studied using the Snowmass Combined LHC detector
implementation in the Delphes simulation package, as well as the Letter of
Intent or Technical Design Report simulations of the ILD detector concept at
the ILC. We investigated both the LHC and ILC capabilities for discovery,
separation and identification of all parts of the spectrum. While parts of the
spectrum would be discovered at the LHC, there is substantial room for further
discoveries and property determination at the ILC.


title:
Corotation resonance and overstable oscillations in black-hole accretion
  discs: general-relativistic calculations

abstract:
  We study the dynamics of spiral waves and oscillation modes in relativistic
rotating discs around black holes. Generalizing the Newtonian theory, we show
that wave absorption can take place at the corotation resonance, where the
pattern frequency of the wave matches the background disc rotation rate. We
derive the general relativistic expression for the disc vortensity (vorticity
divided by surface density), which governs the behaviour of density
perturbation near corotation. Depending on the gradient of the generalized disc
vortensity, corotational wave absorption can lead to the amplification or
damping of the spiral wave. We apply our general theory of relativistic wave
dynamics to calculate the non-axisymmetric inertial-acoustic modes (also called
p-modes) trapped in the inner-most region of a black hole accretion disc.
Because general relativity changes the profiles of the radial epicyclic
frequency and disc vortensity near the inner disc edge close to the black hole,
these p-modes can become overstable under appropriate conditions. We present
the numerical results of the frequencies and growth rates of p-modes for
various black hole spin and model disc parameters (the surface density profile
and sound speed), and discuss their implications for understanding the
enigmatic high-frequency quasi-periodic oscillations observed in black hole
X-ray binaries.


title:
Kinetic constraints, hierarchical relaxation and onset of glassiness in
  strongly interacting and dissipative Rydberg gases

abstract:
  We show that the dynamics of a laser driven Rydberg gas in the limit of
strong dephasing is described by a master equation with manifest kinetic
constraints. The equilibrium state of the system is uncorrelated but the
constraints in the dynamics lead to spatially correlated collective relaxation
reminiscent of glasses. We study and quantify the evolution towards equilibrium
in one and two dimensions, and analyze how the degree of glassiness and the
relaxation time are controlled by the interaction strength between Rydberg
atoms. We also find that spontaneous decay of Rydberg excitations leads to an
interruption of glassy relaxation that takes the system to a highly correlated
non-equilibrium stationary state. The results presented here, which are in
principle also applicable other systems such as polar molecules and atoms with
large magnetic dipole moments, show that the collective behavior of cold atomic
and molecular ensembles can be similar to that found in soft condensed-matter
systems.

categories: physics.atom-ph cond-mat.quant-gas cond-mat.soft quant-ph


title: Revisiting the number of simple $K_4$-groups

abstract:
  In this paper, by solving Diophantine equations involving simple
$K_4$-groups, we will try to point out that it is not easy to prove the
infinitude of simple $K_4$-groups. This problem goes far beyond what is known
about Dickson's conjecture at present.


title: Snowmass 2013 Young Physicists Science and Career Survey Report

abstract:
  From April to July 2013 the Snowmass Young Physicists (SYP) administered an
online survey collecting the opinions and concerns of the High Energy Physics
(HEP) community. The aim of this survey is to provide input into the long term
planning meeting known as the Community Summer Study (CSS), or Snowmass on the
Mississippi. In total, 1112 respondents took part in the survey including 74
people who had received their training within HEP and have since left for
non-academic jobs. This paper presents a summary of the survey results
including demographic, career outlook, planned experiments and non-academic
career path information collected.


title:
Proof of the most general multiple-scalar field theory in Minkowski
  space-time free of Ostrogradski Ghost

abstract:
  We give a proof of the most general multiple scalar field theory in flat
space-time free of Ostrogradski ghosts. We start from the assumption that the
action is a functional of the scalar fields and their derivatives of order upto
two (which in general can have field equations of derivative order up to four),
and arrive at the most-general field theory that can be constructed such that
the field equations are of derivative order up to two. Naturally, this theory
includes all physically viable multi-scalar field theories in flat space-time,
in the sense that they don't suffer from Ostrogradski instability \cite{ostro}.


title: A multidimensional version of noise stability

abstract:
  We give a multivariate generalization of Borell's noise stability theorem for
Gaussian vectors. As a consequence we recover two inequalities, also due to
Borell, for exit times of the Ornstein-Uhlenbeck process.


title:
TOFEC: Achieving Optimal Throughput-Delay Trade-off of Cloud Storage
  Using Erasure Codes

abstract:
  Our paper presents solutions using erasure coding, parallel connections to
storage cloud and limited chunking (i.e., dividing the object into a few
smaller segments) together to significantly improve the delay performance of
uploading and downloading data in and out of cloud storage.
  TOFEC is a strategy that helps front-end proxy adapt to level of workload by
treating scalable cloud storage (e.g. Amazon S3) as a shared resource requiring
admission control. Under light workloads, TOFEC creates more smaller chunks and
uses more parallel connections per file, minimizing service delay. Under heavy
workloads, TOFEC automatically reduces the level of chunking (fewer chunks with
increased size) and uses fewer parallel connections to reduce overhead,
resulting in higher throughput and preventing queueing delay. Our trace-driven
simulation results show that TOFEC's adaptation mechanism converges to an
appropriate code that provides the optimal delay-throughput trade-off without
reducing system capacity. Compared to a non-adaptive strategy optimized for
throughput, TOFEC delivers 2.5x lower latency under light workloads; compared
to a non-adaptive strategy optimized for latency, TOFEC can scale to support
over 3x as many requests.


title:
Combining Answer Set Programming and POMDPs for Knowledge Representation
  and Reasoning on Mobile Robots

abstract:
  For widespread deployment in domains characterized by partial observability,
non-deterministic actions and unforeseen changes, robots need to adapt sensing,
processing and interaction with humans to the tasks at hand. While robots
typically cannot process all sensor inputs or operate without substantial
domain knowledge, it is a challenge to provide accurate domain knowledge and
humans may not have the time and expertise to provide elaborate and accurate
feedback. The architecture described in this paper combines declarative
programming and probabilistic reasoning to address these challenges, enabling
robots to: (a) represent and reason with incomplete domain knowledge, resolving
ambiguities and revising existing knowledge using sensor inputs and minimal
human feedback; and (b) probabilistically model the uncertainty in sensor input
processing and navigation. Specifically, Answer Set Programming (ASP), a
declarative programming paradigm, is combined with hierarchical partially
observable Markov decision processes (POMDPs), using domain knowledge to revise
probabilistic beliefs, and using positive and negative observations for early
termination of tasks that can no longer be pursued. All algorithms are
evaluated in simulation and on mobile robots locating target objects in indoor
domains.


title:
Phase-Space Berry Phases in Chiral Magnets: Dzyaloshinskii-Moriya
  Interaction and the Charge of Skyrmions

abstract:
  The semiclassical motion of electrons in phase space, x=(R, k), is influenced
by Berry phases described by a 6-component vector potential, A=(A^R, A^k). In
chiral magnets Dzyaloshinskii-Moriya (DM) interactions induce slowly varying
magnetic textures (helices and skyrmion lattices) for which all components of A
are important inducing effectively a curvature in mixed position and momentum
space. We show that for smooth textures and weak spin-orbit coupling phase
space Berry curvatures determine the DM interactions and give important
contributions to the charge. Using ab initio methods we calculate the strength
of DM interactions in MnSi in good agreement with experiment and estimate the
charge of skyrmions.


title:
Quasinormal modes of nearly extremal Kerr spacetimes: spectrum
  bifurcation and power-law ringdown

abstract:
  We provide an in-depth investigation of quasinormal-mode oscillations of Kerr
black holes with nearly extremal angular momenta. We first discuss in greater
detail the two distinct types of quasinormal mode frequencies presented in a
recent paper (arXiv:1212.3271). One set of modes, that we call "zero-damping
modes", has vanishing imaginary part in the extremal limit, and exists for all
corotating perturbations (i.e., modes with azimuthal index m being
nonnegative). The other set (the "damped modes") retains a finite decay rate
even for extremal Kerr black holes, and exists only for a subset of corotating
modes. As the angular momentum approaches its extremal value, the frequency
spectrum bifurcates into these two distinct branches when both types of modes
are present. We discuss the physical reason for the mode branching by
developing and using a bound-state formulation for the perturbations of generic
Kerr black holes. We also numerically explore the specific case of the
fundamental l=2 modes, which have the greatest astrophysical interest. Using
the results of these investigations, we compute the quasinormal mode response
of a nearly extremal Kerr black hole to perturbations. We show that many
superimposed overtones result in a slow power-law decay of the quasinormal
ringing at early times, which later gives way to exponential decay. This
exceptional early-time power-law decay implies that the ringdown phase is
long-lived for black holes with large angular momentum, which could provide a
promising strong source for gravitational-wave detectors.


title: New and general framework for adsorption processes on dynamic interfaces

abstract:
  We introduce a new and general continuum thermodynamic framework for the
mathematical analysis and computation of adsorption on dynamic interfaces. To
the best of our knowledge, there is no formulation available that accounts for
the coupled dynamics of interfaces and densities of adsorbants. Our framework
leads to analytic adsorption isotherms which also take the interfacial geometry
fully into account. We demonstrate the utility and physical consistency of our
framework with a new computational multi-level discretization strategy. In the
computations, we recover the experimentally observed feature that the
adsorption of particles minimizes the interfacial tension.

categories: physics.flu-dyn math-ph math.MP nlin.AO physics.chem-ph physics.comp-ph


title:
Riesz-Schwartz extensive quantities and vector-valued integration in
  closed categories

abstract:
  We develop aspects of functional analysis in an abstract axiomatic setting,
through monoidal and enriched category theory. We work in a given closed
category, whose objects we call spaces, and we study R-module objects therein
(or algebras of a commutative monad), which we call linear spaces. Building on
ideas of Lawvere and Kock, we study functionals on the space of scalar-valued
maps, including compactly-supported Radon measures and Schwartz distributions.
We develop an abstract theory of vector-valued integration with respect to
these scalar functionals and their relatives. We study three axiomatic
approaches to vector integration, including an abstract Pettis-type integral,
showing that all are encompassed by an axiomatization via monads and that all
coincide in suitable contexts. We study the relation of this vector integration
to relative notions of completeness in linear spaces. One such notion of
completeness, defined via enriched orthogonality, determines a symmetric
monoidal closed reflective subcategory consisting of exactly those separated
linear spaces that support the vector integral. We prove Fubini-type theorems
for the vector integral. Further, we develop aspects of several supporting
topics in category theory, including enriched orthogonality and factorization
systems, enriched associated idempotent monads and adjoint factorization,
symmetric monoidal adjunctions and commutative monads, and enriched commutative
algebraic theories.


title: Up-type quark masses in SU(5) F-theory models

abstract:
  F-theory SU(5) unification has been proposed as a scenario where the mass of
the top quark is naturally large, as opposed to type II SU(5) models. We
analyze this claim from the viewpoint of local SU(5) F-theory models, by
explicitly computing the 10 x 10 x 5 Yukawa couplings that are developed in the
vicinity of an E6 singularity. Realizing this singularity via T-branes allows
for a non-trivial mass for the top quark, while lighter generations of up-type
quarks still have vanishing Yukawa couplings. Nevertheless, we show that by
taking instanton effects into account non-vanishing Yukawas are induced for all
U-quark families, together with a hierarchical structure at the level of the
superpotential. Finally, by solving for internal wavefunction profiles we
compute physical U-quark Yukawa couplings and show that this F-theory scenario
allows to describe the measured top quark mass, as well as the observed
quotients of U-quark masses.


title:
Stochastic Heating, Differential Flow, and the Alpha-to-Proton
  Temperature Ratio in the Solar Wind

abstract:
  We extend previous theories of stochastic ion heating to account for the
motion of ions along the magnetic field. We derive an analytic expression for
the ion-to-proton perpendicular temperature ratio in the solar wind for any ion
species, assuming that stochastic heating is the dominant ion heating
mechanism. This expression describes how this temperature ratio depends upon
the average velocity of the ions along the magnetic field direction and the
ratio of the parallel proton pressure to the magnetic pressure. We compare our
model with previously published measurements of alpha particles and protons
from the WIND spacecraft. We find that stochastic heating offers a promising
explanation for these measurements when the fractional cross helicity and
Alfven ratio at the proton-gyroradius scale have values that are broadly
consistent with solar-wind measurements.


title:
VERITAS results from a three-year observing campaign on the BL Lac
  object 1ES 0229+200

abstract:
  The BL Lac object 1ES 0229+200 is a firmly established very-high-energy (VHE;
E >100 GeV) source. Located at a redshift of 0.1396, its published VHE spectrum
is particularly hard (Gamma ~2.5) and is widely used to perform studies on the
extragalactic background light (EBL) and the intergalactic magnetic field
(IGMF). We present here the results of a long-term observing campaign on 1ES
0229+200 with VERITAS, lasting from 2009 to 2012, supported by multi-wavelength
observations. We discuss the VERITAS results with a particular emphasis on the
implications for the synchrotron-self-Compton modeling of the source emission
and for the theoretical studies (especially on the intergalactic magnetic
field) based on its VHE spectrum.


title: Constraining conformal field theories with a higher spin symmetry in d=4

abstract:
  We study unitary conformal field theories with a unique stress tensor and at
least one higher-spin conserved current in four dimensions. We prove that every
such theory contains an infinite number of higher-spin conserved currents of
arbitrarily high spin, and that Ward identities generated by the conserved
charges of these currents suffice to completely fix the correlators of the
stress tensor and the conserved currents to be equal to one of three free field
theories: the free boson, the free fermion, and the free vector field. This is
a generalization of the result proved in three dimensions by Maldacena and
Zhiboedov [arXiv:1112.1016].


title:
The resurgent character of the Fatou coordinates of a simple parabolic
  germ

abstract:
  Given a holomorphic germ at the origin of C with a simple parabolic fixed
point, the local dynamics is classically described by means of pairs of
attracting and repelling Fatou coordinates and the corresponding pairs of horn
maps, of crucial importance for \'Ecalle-Voronin's classification result and
the definition of the parabolic renormalization operator. We revisit \'Ecalle's
approach to the construction of Fatou coordinates, which relies on
Borel-Laplace summation, and give an original and self-contained proof of their
resurgent character.


title: On spectrum of ILW hierarchy in conformal field theory

abstract:
  We consider a system of Integrals of Motion in conformal field theory related
to the gl(2) Intermediate Long Wave equation. It interpolates between the
system studied by Bazhanov, Lukyanov and Zamolodchikov and the one studied by
the author and collaborators. We find Bethe anzatz equations for the spectrum
of this system and its gl(n) generalizations.


title: On the resurgent approach to Ecalle-Voronin's invariants

abstract:
  Given a holomorphic germ at the origin of C with a simple parabolic fixed
point, the Fatou coordinates have a common asymptotic expansion whose formal
Borel transform is resurgent. We show how to use Ecalle's alien operators to
study the singularities in the Borel plane and relate them to the horn maps,
providing each of Ecalle-Voronin's invariants in the form of a convergent
numerical series. The proofs are original and self-contained, with ordinary
Borel summability as the only prerequisite.


title: Phonon-enhanced relaxation and excitation in the Holstein-Hubbard model

abstract:
  We study quenches of the interaction and electron-phonon coupling parameter
in the Hubbard-Holstein model, using nonequilibrium dynamical mean field
theory. The calculations are based on a generalized Lang-Firsov scheme for
time-dependent interactions or externally driven phonons, and an approximate
strong-coupling impurity solver. The interaction quench calculations reveal the
phonon-assisted decay of excess doublons, while the quenches of the
electron-phonon coupling lead to persistent oscillations of the phonons and to
a phonon-enhanced doublon production.


title: The transition matroid of a 4-regular graph: an introduction

abstract:
  Given a 4-regular graph $F$, we introduce a binary matroid $M_{\tau}(F)$ on
the set of transitions of $F$. Parametrized versions of the Tutte polynomial of
$M_{\tau}(F)$ yield several well-known graph and knot polynomials, including
the Martin polynomial, the homflypt polynomial, the Kauffman polynomial and the
Bollob\'as-Riordan polynomial.


title:
Equation of State of hot and dense QCD: Resummed perturbation theory
  confronts lattice data

abstract:
  We perform a detailed analysis of the predictions of resummed perturbation
theory for the pressure and the second-, fourth-, and sixth-order diagonal
quark number susceptibilities in a hot and dense quark-gluon plasma. First, we
present an exact one-loop calculation of the equation of state within
hard-thermal-loop perturbation theory (HTLpt) and compare it to a previous
one-loop HTLpt calculation that employed an expansion in the ratios of thermal
masses and the temperature. We find that this expansion converges reasonably
fast. We then perform a resummation of the existing four-loop weak coupling
expression for the pressure, motivated by dimensional reduction. Finally, we
compare the exact one-loop HTLpt and resummed dimensional reduction results
with state-of-the-art lattice calculations and a recent mass-expanded
three-loop HTLpt calculation.


title: Spin Polarized Photons and Di-leptons from Axially Charged Plasma

abstract:
  Axial charge in a QCD plasma is P- and CP-odd. We propose and study P- and
CP-odd observables in photon and di-lepton emissions from an axially charged
QCD plasma, which may provide possible experimental evidences of axial charge
fluctuation and triangle anomaly in the plasma created in heavy-ion collisions.
Our observables measure spin alignments of the emitted photons and di-leptons,
and are shown to be related to the imaginary part of chiral magnetic
conductivity at finite frequency-momentum, which ultimately arises from the
underlying triangle anomaly of the QCD plasma with a finite axial charge
density. We present an exemplar computation of these observables in strongly
coupled regime using AdS/CFT correspondence.


title: Holographic Superfluids and the Landau Criterion

abstract:
  We revisit the question of stability of holographic superfluids with finite
superfluid velocity. Our method is based on applying the Landau criterion to
the Quasinormal Mode (QNM) spectrum. In particular we study the QNMs related to
the Goldstone modes of spontaneous symmetry breaking with linear and quadratic
dispersions.In the linear case we show that the sound velocity becomes negative
for large enough superfluid velocity and that the imaginary part of the
quasinormal frequency moves to the upper half plane. Since the instability is
strongest at finite wavelength, we take this as an indication for the existence
of an inhomogeneous or striped condensed phase for large superfluid velocity.
In the quadratic case the instability is present for arbitrarily small
superfluid velocity.


title:
Improved Particle Identification Using Cluster Counting in a Full-Length
  Drift Chamber Prototype

abstract:
  Single-cell prototype drift chambers were built at TRIUMF and tested with a
$\sim\unit[210]{MeV/c}$ beam of positrons, muons, and pions. A cluster-counting
technique is implemented which improves the ability to distinguish muons and
pions when combined with a traditional truncated-mean charge measurement.
Several cluster-counting algorithms and equipment variations are tested, all
showing significant improvement when combined with the traditional method. The
results show that cluster counting is a feasible option for any particle
physics experiment using drift chambers for particle identification. The
technique does not require electronics with an overly high sampling rate.
Optimal results are found with a signal smoothing time of $\sim\unit[5]{ns}$
corresponding to a $\sim\unit[100]{MHz}$ Nyquist frequency.


title:
A precise determination of top quark electro-weak couplings at the ILC
  operating at $\roots=500\,\GeV$

abstract:
  Top quark production in the process $e^+e^- \rightarrow t\bar{t}$ at a future
linear electron positron collider with polarised beams is a powerful tool to
determine indirectly the scale of new physics. The presented study, based on a
detailed simulation of the ILD detector concept, assumes a centre-of-mass
energy of $\roots=500$\,GeV and a luminosity of $\mathcal{L}=500\,\invfb$
equality shared between the incoming beam polarisations of $P_{e^{-,+}}
=\pm0.8,\mp0.3$. Events are selected in which the top pair decays
semi-leptonically. The study comprises the cross sections, the forward-backward
asymmetry and the slope of the helicity angle asymmetry. The vector, axial
vector and tensorial CP conserving couplings are separately determined for the
photon and the $Z^0$ component. The sensitivity to new physics would be
dramatically improved with respect to what is expected from LHC for electroweak
couplings.


title: Why Are There So Few Perovskite Ferroelectrics?

abstract:
  We use a combination of symmetry arguments and first-principles calculations
to explore the connection between structural distortions and ferroelectricity
in the perovskite family of materials. We explain the role of octahedral
rotations in suppressing ferroelectricity in these materials and show that, as
the tolerance factor decreases, rotations alone cannot fully suppress
ferroelectricity. Our results show that it is cation displacements (`hidden' in
Glazer notation) that accompany the rotations, rather than the rotations
themselves, that play the decisive role in suppressing ferroelectricity in
these cases. We use the knowledge gained in our analysis of this problem to
explain the origin of ferroelectricity in $R3c$ materials such as FeTiO$_3$ and
ZnSnO$_3$ and to suggest strategies for the design and synthesis of new
perovskite ferroelectrics. Our results have implications not only for the
fundamental crystal chemistry of the perovskites but also for the discovery of
new functional materials.


title: Neural Network Capacity for Multilevel Inputs

abstract:
  This paper examines the memory capacity of generalized neural networks.
Hopfield networks trained with a variety of learning techniques are
investigated for their capacity both for binary and non-binary alphabets. It is
shown that the capacity can be much increased when multilevel inputs are used.
New learning strategies are proposed to increase Hopfield network capacity, and
the scalability of these methods is also examined in respect to size of the
network. The ability to recall entire patterns from stimulation of a single
neuron is examined for the increased capacity networks.


title: Neutrino-nucleus quasi-elastic and 2p2h interactions up to 10 GeV

abstract:
  We extend to 10 GeV results from a microscopic calculation of charged-current
neutrino-nucleus reactions that do not produce a pion in the final state. For
the class of events coming from neutrino interactions with two nucleons
producing two holes (2p2h), limiting the calculation to three-momentum
transfers less than 1.2 GeV produces a two dimensional distribution in momentum
and energy transfer that is roughly constant as a function of energy. The cross
section for 2p2h interactions scales with the number of nucleons for isoscalar
nuclei, similar to the quasi-elastic (QE) cross section. When limited to
momentum transfers below 1.2 GeV, the cross section is 26% of the QE cross
section at 3 GeV, but 14% if we neglect a Delta1232 resonance absorption
component. The same quantities are 33% and 17% for anti-neutrinos. For the
quasi-elastic interactions, the full nuclear model with long range correlations
produces an even larger, but approximately constant distortion of the shape of
the four-momentum transfer at all energies above 2 GeV. The 2p2h enhancement
and long-range correlation distortions to the cross section for these
interactions is significant enough they should be observable in precision
experiments to measure neutrino oscillations and neutrino interactions at these
energies, but also balance out and produce less total distortion than each
effect does individually.


title: Cyclic Cosmology, Conformal Symmetry and the Metastability of the Higgs

abstract:
  Recent measurements at the LHC suggest that the current Higgs vacuum could be
metastable with a modest barrier (height 10^{10-12}{GeV})^{4}) separating it
from a ground state with negative vacuum density of order the Planck scale. We
note that metastability is problematic for big bang to end one cycle, bounce,
and begin the next. In this paper, motivated by the approximate scaling
symmetry of the standard model of particle physics and the primordial
large-scale structure of the universe, we use our recent formulation of the
Weyl-invariant version of the standard model coupled to gravity to track the
evolution of the Higgs in a regularly bouncing cosmology. We find a band of
solutions in which the Higgs field escapes from the metastable phase during
each big crunch, passes through the bang into an expanding phase, and returns
to the metastable vacuum, cycle after cycle after cycle. We show that, due to
the effect of the Higgs, the infinitely cycling universe is geodesically
complete, in contrast to inflation.


title:
On Lie algebras arising from $p$-adic representations in the imperfect
  residue field case

abstract:
  Let $K$ be a complete discrete valuation field of mixed characteristic
$(0,p)$ with residue field $k_K$ such that $[k_K:k_K^p]=p^d<\infty$. Let $G_K$
be the absolute Galois group of $K$ and $\rho:G_K\to GL_h(\Q_p)$ a $p$-adic
representation. When $k_K$ is perfect, Shankar Sen described the Lie algebra of
$\rho(G_K)$ in terms of so-called Sen's operator $\Theta$ for $\rho$. When
$k_K$ may not be perfect, Olivier Brinon defined $d+1$ operators
$\Theta_0,...,\Theta_d$ for $\rho$, which coincides with Sen's operator
$\Theta$ in the case of $d=0$. In this paper, we describe the Lie algebra of
$\rho(G_K)$ in terms of Brinon's operators $\Theta_0,...,\Theta_d$, which is a
generalization of Sen's result.


title: Deformations of zero-dimensional schemes and applications

abstract:
  In this thesis we consider the geometry of the Hilbert scheme of points in
P^n, concentrating on the locus of points corresponding to the Gorenstein
subschemes of P^n. New results are given, most importantly we provide tools for
constructing flat families and analysis of finite Gorenstein algebras and
expose their efficiency by proving smoothability of certain families of
algebras. Much of the existing theory and folklore is reviewed, providing a
micro-encyclopaedic reference.


title: Homogeneity Groups of Ends of 3-manifolds

abstract:
  For every finitely generated abelian group G, we construct an irreducible
open 3-manifold $M_{G}$ whose end set is homeomorphic to a Cantor set and with
end homogeneity group of $M_{G}$ isomorphic to G. The end homogeneity group is
the group of self-homeomorphisms of the end set that extend to homeomorphisms
of the 3-manifold. The techniques involve computing the embedding homogeneity
groups of carefully constructed Antoine type Cantor sets made up of rigid
pieces. In addition, a generalization of an Antoine Cantor set using infinite
chains is needed to construct an example with integer homogeneity group.
Results about local genus of points in Cantor sets and about geometric index
are also used.


title:
On differential modules associated to de Rham representations in the
  imperfect residue field case

abstract:
  Let $K$ be a complete discrete valuation field of mixed characteristic
$(0,p)$, whose residue field may not be perfect, and $G_K$ the absolute Galois
group of $K$. In the first part of this paper, we prove that Scholl's
generalization of fields of norms over $K$ is compatible with Abbes-Saito's
ramification theory. In the second part, we construct a functor
$\mathbb{N}_{\mathrm{dR}}(V)$ associating a de Rham representation $V$ with a
$(\varphi,\nabla)$-module in the sense of Kedlaya. Finally, we prove a
compatibility between Kedlaya's differential Swan conductor of
$\mathbb{N}_{\mathrm{dR}}(V)$ and Swan conductor of $V$, which generalizes
Marmora's formula.


title:
Inequivalent Cantor Sets in $R^{3}$ Whose Complements Have the Same
  Fundamental Group

abstract:
  For each Cantor set C in $R^{3}$, all points of which have bounded local
genus, we show that there are infinitely many inequivalent Cantor sets in
$R^{3}$ with complement having the same fundamental group as the complement of
C. This answers a question from Open Problems in Topology and has as an
application a simple construction of nonhomeomorphic open 3-manifolds with the
same fundamental group. The main techniques used are analysis of local genus of
points of Cantor sets, a construction for producing rigid Cantor sets with
simply connected complement, and manifold decomposition theory. The results
presented give an argument that for certain groups G, there are uncountably
many nonhomeomorphic open 3-manifolds with fundamental group G.


title:
Visualization and Analysis of Geographical Crime Patterns Using Formal
  Concept Analysis

abstract:
  There are challenges faced in today's world in terms of crime analysis when
it comes to graphical visualization of crime patterns. Geographical
representation of crime scenes and crime types become very important in
gathering intelligence about crimes. This provides a very dynamic and easy way
of monitoring criminal activities and analyzing them as well as producing
effective countermeasures and preventive measures in solving them. But we need
effective computer tools and intelligent systems that are automated to analyze
and interpret criminal data in real time effectively and efficiently. These
current computer systems should have the capability of providing intelligence
from raw data and creating a visual graph which will make it easy for new
concepts to be built and generated from crime data in order to solve,
understand and analyze crime patterns easily. This paper proposes a new method
of visualizing and analyzing crime patterns based on geographical crime data by
using Formal Concept Analysis, or Galois Lattices, a data analysis technique
grounded on Lattice Theory and Propositional Calculus. This method considered
the set of common and distinct attributes of crimes in such a way that
categorization are done based on related crime types. This will help in
building a more defined and conceptual systems for analysis of geographical
crime data that can easily be visualized and intelligently analyzed by computer
systems.


title: BL Lac candidates for TeV observations

abstract:
  BL Lac objects are the most numerous class of extragalactic TeV-detected
sources. One of the biggest difficulties in investigating their TeV emission
resides in their limited number, since only 47 BL Lacs are known as TeV
emitters. In this paper, we propose new criteria to select TeV BL Lac
candidates based on the infrared (IR) and X-ray observations. We apply our
selection criteria to the BL Lac objects listed in the ROMA-BZCAT catalog so
identifying 41 potential TeV emitters. We then consider a search over a more
extended sample combining the ROSAT bright source catalog and the WISE all-sky
survey revealing 54 additional candidates for TeV observations. Our
investigation also led to a tentative classification of 16 unidentified X-ray
sources as BL Lac candidates. This analysis provides new interesting BL Lac
targets for future observations with ground based Cherenkov telescopes.


title: The squeezed limit of the solid inflation three-point function

abstract:
  The recently proposed model of 'solid inflation' features a peculiar
three-point function for scalar perturbations with an anisotropic, purely
quadrupolar, squeezed limit. We confirm this result as well as the overall
amplitude of the three point-function via an extremely simple computation,
where we focus on the squeezed limit from the start and follow the standard
logic adopted in deriving the consistency relations. Our system violates the
consistency relations, but in the squeezed limit the three-point function can
still be traded for a background-dependent two-point function, which is
immediate to compute. Additionally, we use these simple methods to derive some
new results - namely, certain squeezed limits of the three-point correlators
involving vector and tensor perturbations as well.


title:
Ionization Break-Out from Millisecond Pulsar Wind Nebulae: an X-ray
  Probe of the Origin of Superluminous Supernovae

abstract:
  Magnetic spin-down of a millisecond neutron star has been proposed as the
power source of hydrogen-poor "superluminous" supernovae (SLSNe-I). However,
producing an unambiguous test that can distinguish this model from
alternatives, such as circumstellar interaction, has proven challenging. After
the supernova explosion, the pulsar wind inflates a hot cavity behind the
expanding stellar ejecta: the nascent millisecond pulsar wind nebula.
Electron/positron pairs injected by the wind cool through inverse Compton
scattering and synchrotron emission, producing a pair cascade and hard X-ray
spectrum inside the nebula. These X-rays ionize the inner exposed side of the
ejecta, driving an ionization front that propagates outwards with time. Under
some conditions this front can breach the ejecta surface within months after
the optical supernova peak, allowing ~0.1-1 keV photons to escape the nebula
unattenuated with a characteristic luminosity L_X ~ 1e43-1e45 erg/s. This
"ionization break-out" may explain the luminous X-ray emission observed from
the transient SCP 06F, providing direct evidence that this SLSN was indeed
engine-powered. Luminous break-out requires a low ejecta mass and that the
spin-down time of the pulsar be comparable to the photon diffusion timescale at
optical maximum, the latter condition similar to that required for a supernova
with a high optical fluence. These relatively special requirements may explain
why most SLSNe-I are not accompanied by detectable X-ray emission. Global
asymmetry of the supernova ejecta increases the likelihood of an early
break-out along the direction of lowest density. Atomic states with lower
threshold energies are more readily ionized at earlier times near optical
maximum, allowing UV break-out across a wider range of pulsar and ejecta
properties than X-ray break-out, possibly contributing to the blue/UV colors of
SLSNe-I.


title:
A new code for orbit analysis and Schwarzschild modelling of triaxial
  stellar systems

abstract:
  We review the methods used to study the orbital structure and chaotic
properties of various galactic models and to construct self-consistent
equilibrium solutions by Schwarzschild's orbit superposition technique. These
methods are implemented in a new publicly available software tool, SMILE, which
is intended to be a convenient and interactive instrument for studying a
variety of 2D and 3D models, including arbitrary potentials represented by a
basis-set expansion, a spherical-harmonic expansion with coefficients being
smooth functions of radius (splines), or a set of fixed point masses. We also
propose two new variants of Schwarzschild modelling, in which the density of
each orbit is represented by the coefficients of the basis-set or spline
spherical-harmonic expansion, and the orbit weights are assigned in such a way
as to reproduce the coefficients of the underlying density model. We explore
the accuracy of these general-purpose potential expansions and show that they
may be efficiently used to approximate a wide range of analytic density models
and serve as smooth representations of discrete particle sets (e.g. snapshots
from an N-body simulation), for instance, for the purpose of orbit analysis of
the snapshot. For the variants of Schwarzschild modelling, we use two test
cases - a triaxial Dehnen model containing a central black hole, and a model
re-created from an N-body snapshot obtained by a cold collapse. These tests
demonstrate that all modelling approaches are capable of creating equilibrium
models.


title: Entanglement does not generally decrease under renormalization

abstract:
  Renormalization is often described as the removal or "integrating out" of
high energy degrees of freedom. In the context of quantum matter, one might
suspect that quantum entanglement provides a sharp way to characterize such a
loss of degrees of freedom. Indeed, for quantum many-body systems with Lorentz
invariance, such entanglement monotones have been proven to exist in one, two,
and three spatial dimensions. In each dimension d, a certain term in the
entanglement entropy of a d-ball decreases along renormalization group (RG)
flows. Given that most quantum many-body systems available in the laboratory
are not Lorentz invariant, it is important to generalize these results if
possible. In this work we demonstrate the impossibility of a wide variety of
such generalizations. We do this by exhibiting a series of counterexamples with
understood renormalization group flows which violate entanglement RG
monotonicity. We discuss bosons at finite density, fermions at finite density,
and majorization in Lorentz invariant theories, among other results.


title:
Accurate determination of accretion and photospheric parameters in Young
  Stellar Objects: the case of two candidate old disks in the Orion Nebula
  Cluster

abstract:
  Current planet formation models are largely based on the observational
constraint that protoplanetary disks have lifetime 3Myr. Recent studies,
however, report the existence of PMS stars with signatures of accretion
(strictly connected with the presence of circumstellar disks)and
photometrically determined ages of 30 Myr, or more. Here we present a
spectroscopic study of two major age outliers in the ONC. We use broad band,
intermediate resolution VLT/X-Shooter spectra combined with an accurate method
to determine the stellar parameters and the related age of the targets to
confirm their peculiar age estimates and the presence of ongoing accretion.The
analysis is based on a multi-component fitting technique, which derives
simultaneously SpT, extinction, and accretion properties of the objects. With
this method we confirm and quantify the ongoing accretion. From the
photospheric parameters of the stars we derive their position on the HRD, and
the age given by evolutionary models. Together with other age indicators like
the lithium equivalent width we estimate with high accuracy the age of the
objects. Our study shows that the two objects analyzed are not older than the
typical population of the ONC. Our results show that, while photometric
determination of the photospheric parameters are an accurate method to estimate
the parameters of the bulk of young stellar populations, those of individual
objects with high accretion rates and extinction may be affected by large
uncertainties. Broad band spectroscopic determinations should thus be used to
confirm the nature of individual objects. Our analysis shows that this method
allows us to obtain an accurate determination of the photospheric parameters of
accreting YSOs in any nearby star-forming region. We suggest that our detailed,
broad- band spectroscopy method should be used to derive accurate properties of
candidate old and accreting YSOs.


title:
First order resonance overlap and the stability of close two planet
  systems

abstract:
  Motivated by the population of multi-planet systems with orbital period
ratios 1<P2/P1<2, we study the long-term stability of packed two planet
systems. The Hamiltonian for two massive planets on nearly circular and nearly
coplanar orbits near a first order mean motion resonance can be reduced to a
one degree of freedom problem (Sessin & Ferraz Mello (1984), Wisdom (1986),
Henrard et al. (1986)). Using this analytically tractable Hamiltonian, we apply
the resonance overlap criterion to predict the onset of large scale chaotic
motion in close two planet systems. The reduced Hamiltonian has only a weak
dependence on the planetary mass ratio, and hence the overlap criterion is
independent of the planetary mass ratio at lowest order. Numerical integrations
confirm that the planetary mass ratio has little effect on the structure of the
chaotic phase space for close orbits in the low eccentricity (e <~0.1) regime.
We show numerically that orbits in the chaotic web produced primarily by first
order resonance overlap eventually experience large scale erratic variation in
semimajor axes and are Lagrange unstable. This is also true of the orbits in
this overlap region which are Hill stable. As a result, we can use the first
order resonance overlap criterion as an effective stability criterion for pairs
of observed planets. We show that for low mass (<~10 M_Earth) planetary systems
with initially circular orbits the period ratio at which complete overlap
occurs and widespread chaos results lies in a region of parameter space which
is Hill stable. Our work indicates that a resonance overlap criterion which
would apply for initially eccentric orbits needs to take into account second
order resonances. Finally, we address the connection found in previous work
between the Hill stability criterion and numerically determined Lagrange
instability boundaries in the context of resonance overlap.


title: Effective WIMPs

abstract:
  The 'WIMP miracle' for the relic abundance of thermal dark matter motivates
weak scale dark matter with renormalizable couplings to standard model
particles. We study minimal models with such couplings that explain dark matter
as a thermal relic. The models contain a singlet dark matter particle with
cubic renormalizable couplings between standard model particles and 'partner'
particles with the same gauge quantum numbers as the standard model particle.
The dark matter has spin 0, 1/2, or 1, and may or may not be its own
antiparticle. Each model has 3 parameters: the masses of the dark matter and
standard model partners, and the cubic coupling. Requiring the correct relic
abundance gives a 2-dimensional parameter space where collider and direct
detection constraints can be directly compared. We focus on the case of dark
matter interactions with colored particles. We find that collider and direct
detection searches are remarkably complementary for these models. Direct
detection limits for the cases where the dark matter is not its own
antiparticle require dark matter masses to be in the multi-TeV range, where
they are extremely difficult to probe in collider experiments. The models where
dark matter is its own antiparticle are strongly constrained by collider
searches for monojet and jets + MET signals. These models are constrained by
direct detection mainly near the limit where the dark matter and partner masses
are nearly degenerate, where collider searches become more difficult.


title:
The SDSS-III APOGEE Radial Velocity Survey of M dwarfs I: Description of
  Survey and Science Goals

abstract:
  We are carrying out a large ancillary program with the SDSS-III, using the
fiber-fed multi-object NIR APOGEE spectrograph, to obtain high-resolution
H-band spectra of more than 1200 M dwarfs. These observations are used to
measure spectroscopic rotational velocities, radial velocities, physical
stellar parameters, and variability of the target stars. Here, we describe the
target selection for this survey and results from the first year of scientific
observations based on spectra that is publicly available in the SDSS-III DR10
data release. As part of this paper we present RVs and vsini of over 200 M
dwarfs, with a vsini precision of ~2 km/s and a measurement floor at vsini = 4
km/s. This survey significantly increases the number of M dwarfs studied for
vsini and RV variability (at ~100-200 m/s), and will advance the target
selection for planned RV and photometric searches for low mass exoplanets
around M dwarfs, such as HPF, CARMENES, and TESS. Multiple epochs of radial
velocity observations enable us to identify short period binaries, and AO
imaging of a subset of stars enables the detection of possible stellar
companions at larger separations. The high-resolution H-band APOGEE spectra
provide the opportunity to measure physical stellar parameters such as
effective temperatures and metallicities for many of these stars. At the
culmination of this survey, we will have obtained multi-epoch spectra and RVs
for over 1400 stars spanning spectral types of M0-L0, providing the largest set
of NIR M dwarf spectra at high resolution, and more than doubling the number of
known spectroscopic vsini values for M dwarfs. Furthermore, by modeling
telluric lines to correct for small instrumental radial velocity shifts, we
hope to achieve a relative velocity precision floor of 50 m/s for bright M
dwarfs. We present preliminary results of this telluric modeling technique in
this paper.


title:
Higgs Strahlung at the Large Hadron Collider in the 2-Higgs-Doublet
  Model

abstract:
  We present a calculation of all relevant contributions to associated
production of a Higgs boson with a weak gauge boson in the 2-Higgs-Doublet
Model (2HDM) at the LHC, $pp \rightarrow V\phi$, with $\phi\in\{h,H^0,A\}$ and
$V\in\{W,Z\}$. While for the $W\phi$ mode, this mostly amounts to a simple
rescaling of the Standard Model (SM) cross section, the $Z\phi$ cross section
depends on several 2HDM parameters. The ratio $\sigma^{W\phi}/\sigma^{Z\phi}$,
for which we present the currently most complete SM prediction, therefore
appears to be a sensitive probe of possible New Physics effects. We study its
numerical dependence on the top and bottom Yukawa couplings, including their
sign. Furthermore, we consider the $W\phi/Z\phi$ ratio in exemplary 2HDM
scenarios and briefly address the effects in the boosted regime. Analogous
studies for other 2HDM scenarios will become possible with an upcoming version
of the program vh@nnlo which incorporates the 2HDM effects.