title: ANANAS - A Framework For Analyzing Android Applications

abstract:
  Android is an open software platform for mobile devices with a large market
share in the smartphone sector. The openness of the system as well as its wide
adoption lead to an increasing amount of malware developed for this platform.
ANANAS is an expandable and modular framework for analyzing Android
applications. It takes care of common needs for dynamic malware analysis and
provides an interface for the development of plugins. Adaptability and
expandability have been main design goals during the development process. An
abstraction layer for simple user interaction and phone event simulation is
also part of the framework. It allows an analyst to script the required user
simulation or phone events on demand or adjust the simulation to his needs. Six
plugins have been developed for ANANAS. They represent well known techniques
for malware analysis, such as system call hooking and network traffic analysis.
The focus clearly lies on dynamic analysis, as five of the six plugins are
dynamic analysis methods.


title: Graphs cospectral with a friendship graph or its complement

abstract:
  Let $n$ be any positive integer and let $F_n$ be the friendship (or Dutch
windmill) graph with $2n+1$ vertices and $3n$ edges. Here we study graphs with
the same adjacency spectrum as the $F_n$. Two graphs are called cospectral if
the eigenvalues multiset of their adjacency matrices are the same. Let $G$ be a
graph cospectral with $F_n$. Here we prove that if $G$ has no cycle of length 4
or 5, then $G\cong F_n$. Moreover if $G$ is connected and planar then $G\cong
F_n$. All but one of connected components of $G$ are isomorphic to $K_2$. The
complement $\bar{F_n}$ of the friendship graph is determined by its adjacency
eigenvalues, that is, if $\bar{F_n}$ is cospectral with a graph $H$, then
$H\cong \bar{F_n}$.


title:
Analytic Extension of the Birkhoff Normal Forms for the Free Rigid Body
  Dynamics on SO(3)

abstract:
  Birkhoff normal form is a power series expansion associated with the local
behavior of the Hamiltonian systems near a critical point. It is known to be
convergent for integrable systems under some non-degeneracy conditions. By
means of an expression of the inverse of Birkhoff normal form by a period
integral, analytic continuation of the Birkhoff normal forms is considered for
the free rigid body dynamics on SO(3). The global behavior of the Birkhoff
normal forms is clarified in relation to the monodromy of an elliptic fibration
which naturally arises from the free rigid body dynamics.


title: Groups all of whose undirected Cayley graphs are integral

abstract:
  Let $G$ be a finite group, $S\subseteq G\setminus\{1\}$ be a set such that if
$a\in S$, then $a^{-1}\in S$, where $1$ denotes the identity element of $G$.
The undirected Cayley graph $Cay(G,S)$ of $G$ over the set $S$ is the graph
whose vertex set is $G$ and two vertices $a$ and $b$ are adjacent whenever
$ab^{-1}\in S$. The adjacency spectrum of a graph is the multiset of all
eigenvalues of the adjacency matrix of the graph. A graph is called integral
whenever all adjacency spectrum elements are integers. Following Klotz and
Sander, we call a group $G$ Cayley integral whenever all undirected Cayley
graphs over $G$ are integral. Finite abelian Cayley integral groups are
classified by Klotz and Sander as finite abelian groups of exponent dividing
$4$ or $6$. Klotz and Sander have proposed the determination of all non-abelian
Cayley integral groups. In this paper we complete the classification of finite
Cayley integral groups by proving that finite non-abelian Cayley integral
groups are the symmetric group $S_{3}$ of degree $3$, $C_{3} \rtimes C_{4}$ and
$Q_{8}\times C_{2}^{n}$ for some integer $n\geq 0$, where $Q_8$ is the
quaternion group of order $8$.


title:
Connected contribution to the kernel of the evolution equation for
  3-quark Wilson loop operator

abstract:
  The connected contribution to the kernel of the evolution equation for the
3-quark Wilson loop operator was derived within Balitsky high energy operator
expansion. Its C-odd part was linearized and transferred to the momentum space.


title:
Surfactant micelles: model systems for flow instabilities of complex
  fluids

abstract:
  Complex fluids such as emulsions, colloidal gels, polymer or surfactant
solutions are all characterized by the existence of a "microstructure" which
may couple to an external flow on timescales that are easily probed in
experiments. Such a coupling between flow and microstructure usually leads to
instabilities under relatively weak shear flows that correspond to vanishingly
small Reynolds numbers. Wormlike micellar surfactant solutions appear as model
systems to study two examples of such instabilities, namely shear banding and
elastic instabilities. Focusing on a semidilute sample we show that two
dimensional ultrafast ultrasonic imaging allows for a thorough investigation of
unstable shear-banded micellar flows. In steady state, radial and azimuthal
velocity components are recovered and unveil the original structure of the
vortical flow within an elastically unstable high shear rate band. Furthermore
thanks to an unprecedented frame rate of up to 20,000 fps, transients and fast
dynamics can be resolved, which paves the way for a better understanding of
elastic turbulence.


title: Noninner Automorphisms of Order p for Finite p-Groups of Coclass 2

abstract:
  Every finite $p$-group of coclass 2 has a noninner automorphism of order $p$
leaving the center elementwise fixed.


title:
$p$-Groups for which each outer $p$-automorphism centralizes only $p$
  elements

abstract:
  An automorphism of a group is called outer if it is not an inner
automorphism.
  Let $G$ be a finite $p$-group. Then for every outer $p$-automorphism $\phi$
of $G$ the subgroup $C_G(\phi)=\{x\in G \;|\; x^\phi=x\}$ has order $p$ if and
only if $G$ is of order at most $p^2$.


title: On some Fano manifolds admitting a rational fibration

abstract:
  Let X be a smooth, complex Fano variety. For every prime divisor D in X, we
set c(D):=dim ker(r:H^2(X,R)->H^2(D,R)), where r is the natural restriction
map, and we define an invariant of X as c_X:=max{c(D)|D is a prime divisor in
X}. In a previous paper we showed that c_X<9, and that if c_X>2, then either X
is a product, or X has a flat fibration in Del Pezzo surfaces. In this paper we
study the case c_X=2. We show that up to a birational modification given by a
sequence of flips, X has a conic bundle structure, or an equidimensional
fibration in Del Pezzo surfaces. We also show a weaker property of X when
c_X=1.


title:
Thermally driven classical Heisenberg model in one dimension with a
  local time-varying field

abstract:
  We study thermal transport in the one dimensional classical Heisenberg model
driven by boundary heat baths in presence of a local time varying magnetic
field that acts at one end of the system. The system is studied numerically
using an energy conserving discrete-time odd even dynamics. We find that the
steady state energy current shows thermal resonance as the frequency of the
time- periodic forcing is varied. When the amplitude of the forcing field is
increased the system exhibits multiple resonance peaks instead of a single
peak. Both single and multiresonance survive in the thermodynamic limit and
their magnitudes increase as the average temperature of the system is
decreased. Finally we show that, although a reversed thermal current can be
made to flow through the bulk for a certain range of the forcing frequency, the
system fails to behave as a heat pump, thus revalidating the fact that thermal
pumping is generically absent in such force-driven lattices.


title: How do Viruses Attack Anti-Virus Programs

abstract:
  As the anti-viruses run in a trusted kernel level any loophole in the
anti-virus program can enable attackers to take full control over the computer
system and steal data or do serious damages. Hence the anti-virus engines must
be developed with proper security in mind. The ant-virus should be able to any
type of specially created executable files, compression packages or documents
that are intentionally created to exploit the anti-virus weakness.
  Viruses are present in almost every system even though there are anti-viruses
installed. This is because every anti-virus, however good it may be, leads to
some extent of false positives and false negatives. Our faith on the anti-virus
system often makes us more careless about hygienic habits which increases the
possibility of infection. It is necessary for an anti-virus to detect and
destroy the malware before its own files are detected and destroyed by the
malware.


title:
Thermal Rectification and Negative Differential Thermal Resistance in a
  driven two segment classical Heisenberg chain

abstract:
  We investigate thermal transport in a two segment classical Heisenberg spin
chain with nearest neighbor interaction and in presence of external magnetic
field using computer simulation. The system is thermally driven by heat baths
attached at the two ends and transport properties are studied using an energy
conserving dynamics. We demonstrate that by properly tuning the parameters
thermal rectification can be achieved - the system behaves as a good conductor
of heat along one direction but becomes a bad conductor when the thermal
gradient is reversed and crucially depends on nonlinearity and spatial
asymmetry. Moreover, suitable tuning of the system parameters gives rise to the
counterintuitive and technologically important feature known as the negative
differential thermal resistance (NDTR). We find that the crucial factor
responsible for the emergence of NDTR is a suitable mechanism to impede the
current in the bulk of the system.


title: Pseudopotential model for Dirac electrons in graphene with line defects

abstract:
  We consider electron transport in a planar fermion model containing various
types of line defects modelled by $\delta$--function pseudopotentials with
different matrix coefficients. The transmission probability for electron
transport through the defect line is obtained for various types of
pseudopotentials. For the schematic model considered that may describe a
graphene structure with different types of linear defects, the valley
polarization is obtained.


title: 10 Inventions on Keyboard key layout: A TRIZ based analysis

abstract:
  The standard QWERTY keyboard was developed in the late 1800s for the
typewriters. As people were acquainted with that the same layout was retained
for the computer keyboards. Many people feel that the QWERTY layout is not very
efficient layout and there have been many inventions on different layouts of
character keys.
  In order to improve the key arrangement, two major issues should be
addressed. (i) The improved key arrangement should offer significantly improved
productivity. (ii) The training time for learning the improved key arrangement
should be minimized.
  This article analyzes 10 inventions from US patent database each of which
have proposed a new layout giving us some specific advantage. The inventions
try to achieve one or more of the following advantages, viz., to reduce finger
movements during typing, to achieve speed in data entry, to reduce errors in
typing, making keyboard easy to learn, making easy for children to find keys,
reduce stress in hands and finger and suitability for special purpose
computers.


title:
Regenerative Simulation for Queueing Networks with Exponential or
  Heavier Tail Arrival Distributions

abstract:
  Multiclass open queueing networks find wide applications in communication,
computer and fabrication networks. Often one is interested in steady-state
performance measures associated with these networks. Conceptually, under mild
conditions, a regenerative structure exists in multiclass networks, making them
amenable to regenerative simulation for estimating the steady-state performance
measures. However, typically, identification of a regenerative structure in
these networks is difficult. A well known exception is when all the
interarrival times are exponentially distributed, where the instants
corresponding to customer arrivals to an empty network constitute a
regenerative structure. In this paper, we consider networks where the
interarrival times are generally distributed but have exponential or heavier
tails. We show that these distributions can be decomposed into a mixture of
sums of independent random variables such that at least one of the components
is exponentially distributed. This allows an easily implementable embedded
regenerative structure in the Markov process. We show that under mild
conditions on the network primitives, the regenerative mean and standard
deviation estimators are consistent and satisfy a joint central limit theorem
useful for constructing asymptotically valid confidence intervals. We also show
that amongst all such interarrival time decompositions, the one with the
largest mean exponential component minimizes the asymptotic variance of the
standard deviation estimator.


title:
Optimal estimate for the gradient of Green functions on degenerating
  surfaces and applications

abstract:
  In this paper we prove a uniform estimate for the gradient of the Green
function on a closed Riemann surface, independent of its conformal class, and
we derive compactness results for immersions with L2-bounded second fundamental
form and for riemannian surfaces of uniformly bounded gaussian curvature
entropy.


title: 10 Inventions on improving keyboard efficiency: A TRIZ based analysis

abstract:
  A keyboard is the most important input device for a computer. With the
development of technology a basic keyboard does not want to remain confined
within the basic functionalities of a keyboard, rather it wants to go beyond.
There are several inventions which attempt to improve the efficiency of a
conventional keyboard.
  This article illustrates 10 inventions from US Patent database all of which
have proposed very interesting methods for improving the efficiency of a
computer keyboard. Some interesting inventions include, adding toolbar buttons
on the keyboard, power saving method, keyboard-cooling mechanism, robust
keyboard for public use, keyboard enhancement for children`s use.
  Each of these inventions have been analyzed from TRIZ perspective, in many
cases formulating the Ideal Final Result, contradictions and highlighting the
Inventive Principles used in the solution.


title:
Phase diagrams of voltage-gated oxide interfaces with strong Rashba
  coupling

abstract:
  We propose a model for the two-dimensional electron gas formed at the
interface of oxide heterostructures that includes a Rashba spin-orbit coupling
proportional to an electric field oriented perpendicularly to the interface.
Taking into account the electron density dependence of this electric field
confining the electron gas at the interface, we report the occurrence of a
phase separation instability (signaled by a negative compressibility) for
realistic values of the spin-orbit coupling and of the electronic
band-structure parameters at zero temperature. We extend the analysis to finite
temperatures and in the presence of an in-plane magnetic field, thereby
obtaining two phase diagrams which exhibit a phase separation dome. By varying
the gating potential the phase separation dome may shrink and vanish at zero
temperature into a quantum critical point where the charge fluctuates
dynamically. Similarly the phase separation may be spoiled by a planar magnetic
field even at zero temperature leading to a line of quantum critical points.


title:
Acceleration of electrons by high intensity laser radiation in a
  magnetic field

abstract:
  We consider the acceleration of electrons in vacuum by means of the
circularly-polirized electromagnetic wave, propagating along a magnetic field.
We show that the electron energy growth, when using ultra-short and
ultra-intense laser pulses (10 ps, 10^{18} Bm/cm^2, CO_{2} laser) in the
presence of a magnetic field, may reach up to the value 2,1 Gev. The growth of
the electron energy is shown to increase proportionally with the increase of
the laser intensity and the initial energy of the electron. We find that for
some direction of polarization of the wave, the acceleration of electrons does
not depend on the initial phase of the electromagnetic wave. We estimate the
laser intensity, necessary for the electron acceleration. In addition, we find
the formation length of photon absorption by electrons, due to which one may
choose the required region of the interaction of the electrons with the
electromagnetic wave and magnetic field. We also show that as a result of
acceleration of electrons in the vacuum by laser radiation in a magnetic field
one may obtain electron beam with small energy spread of the order. We also
show that as a result of acceleration of electrons in the vacuum by laser
radiation in a magnetic field one may obtain electron beam with small energy
spread of the order {\delta\epsilon}/{\epsilon} < 10^{-2}.


title:
Probing the anharmonicity of the potential well for magnetic vortex core
  in nanodot

abstract:
  The anharmonicity of the potential well confining the position of the
magnetic vortex core is measured dynamically with a Magnetic Resonance Force
Microscope (MRFM). The stray field of the MRFM tip is used to displace the core
position away from the well minimum. Anharmonicity is then inferred from the
relative frequency shift induced on the eigen-frequency of the vortex core
translational mode. Traces of these shifts are recorded while scanning the tip
above an isolated nanodot, patterned out of a single crystal FeV film. An
analytical framework is proposed to analyze the data. It results in a
quantitative measurement of the anharmonic coefficient found to be positive and
50% of the parabolic contribution. This calibrates the tunability of the
gyrotropic mode by external magnetic fields. In our sample, we observe a
variation of the eigen-frequency as high as +10% for a displacement of the
vortex core to about one third of the nanodot radius.


title:
A review of Monte Carlo simulations for the Bose-Hubbard model with
  diagonal disorder

abstract:
  We review the physics of the Bose-Hubbard model with disorder in the chemical
potential focusing on recently published analytical arguments in combination
with quantum Monte Carlo simulations. Apart from the superfluid and Mott
insulator phases that can occur in this system without disorder, disorder
allows for an additional phase, called the Bose glass phase. The topology of
the phase diagram is subject to strong theorems proving that the Bose Glass
phase must intervene between the superfluid and the Mott insulator and implying
a Griffiths transition between the Mott insulator and the Bose glass. The full
phase diagrams in 3d and 2d are discussed, and we zoom in on the insensitivity
of the transition line between the superfluid and the Bose glass in the close
vicinity of the tip of the Mott insulator lobe. We briefly comment on the
established and remaining questions in the 1d case, and give a short overview
of numerical work on related models.


title: 10 Inventions on keyboard attachments-A TRIZ based analysis

abstract:
  Although the primary objective of the keyboard to input data into the
computer, the advanced keyboards keep various other things in mind, such as,
how to use the same keyboard for various other purposes, or how to use the same
keyboard efficiently by using various other attachments to the keyboard. This
objective led to various inventions on keyboard attachments, some of which are
illustrated below in this article.
  This article illustrates 10 inventions on various keyboard attachments from
US patent database. Each different attachment improves the usability of the
keyboard in some way or other. Some attachments illustrated are template
holders, paper holders, pointing device attachments, mouse pad attachments,
wrist rest attachments, storage device attachments, and multimedia attachments.


title:
Coherent states, 6j symbols and properties of the next to leading order
  asymptotic expansions

abstract:
  We present the first complete derivation of the well-known asymptotic
expansion of the SU(2) 6j symbol using a coherent state approach, in particular
we succeed in computing the determinant of the Hessian matrix. To do so, we
smear the coherent states and perform a partial stationary point analysis with
respect to the smearing parameters. This allows us to transform the variables
from group elements to dihedral angles of a tetrahedron resulting in an
effective action, which coincides with the action of first order Regge calculus
associated to a tetrahedron. To perform the remaining stationary point
analysis, we compute its Hessian matrix and obtain the correct measure factor.
Furthermore, we expand the discussion of the asymptotic formula to next to
leading order terms, prove some of their properties and derive a recursion
relation for the full 6j symbol.


title: Universality of comb structures in strong-field QED

abstract:
  We demonstrate a new mechanism for coherent comb generation in both radiation
and matter domains, which is by using strong-field quantum electrodynamics
processes. Specifically, we demonstrate this for nonlinear Compton scattering
which has the potential to generate frequency combs extending towards the
$\gamma$-ray spectral region as well as combs of ultra-relativistic electrons
extending towards the MeV regime. Moreover, we show that coherent energy combs
of positrons (or electrons) emerge in laser-induced pair creation processes
such as the Breit-Wheeler process, proving the universality of the proposed
mechanism.


title: Stability of discoidal high-density lipoprotein particles

abstract:
  Motivated by experimental and numerical studies revealing that discoidal
high-density lipoprotein (HDL) particles may adopt flat elliptical and
nonplanar saddle-like configurations, it is hypothesized that these might
represent stabilized configurations of initially unstable flat circular
particles. A variational description is developed to explore the stability of a
flat circular discoidal HDL particle. While the lipid bilayer is modeled as
two-dimensional fluid film endowed with surface tension and bending elasticity,
the apoA-I belt is modeled as one-dimensional inextensible twist-free chain
endowed with bending elasticity. Stability is investigated using the second
variation of the underlying energy functional. Various planar and nonplanar
instability modes are predicted and corresponding nondimensional critical
values of salient dimensionless parameters are obtained. The results predict
that the first planar and nonplanar unstable modes occur due to in-plane
elliptical and transverse saddle-like perturbations. Based on available data,
detailed stability diagrams indicate the range of input parameters for which a
flat circular discoidal HDL particle is linearly stable or unstable.


title:
Distributed Computation of the Conditional PCRLB for Quantized
  Decentralized Particle Filters

abstract:
  The conditional posterior Cramer-Rao lower bound (PCRLB) is an effective
sensor resource management criteria for large, geographically distributed
sensor networks. Existing algorithms for distributed computation of the PCRLB
(dPCRLB) are based on raw observations leading to significant communication
overhead to the estimation mechanism. This letter derives distributed
computational techniques for determining the conditional dPCRLB for quantized,
decentralized sensor networks (CQ/dPCRLB). Analytical expressions for the
CQ/dPCRLB are derived, which are particularly useful for particle filter-based
estimators. The CQ/dPCRLB is compared for accuracy with its centralized
counterpart through Monte-Carlo simulations.


title:
Entropy Production gives rise to Upper- and Lower-Bounds to Efficiency
  and COP of Cycles

abstract:
  From thermodynamics point of view, in this era of aiming at energy
conservation and sustainability, we need to develop more accurate ways to
design thermal power, cooling and heat pump cycles. It has been the general
practice in thermodynamic analysis of cycles to use the Carnot efficiency and
Carnot coefficient of performance which are the highest upper bound to
efficiency and COP of cycles. In the present report through the application of
the second law of thermodynamics for irreversible processes, which results in
the general inequality relation for the entropy production, we have introduce
new upper- and lower-bounds to the efficiency of thermal power cycles and COP
of cooling and heat pump cycles. The resulting upper- and lower-bounds are
closer to the actual efficiency and COP of cycles. That allows us a more
precise design of cycles and the choice of cycles working fluids.


title: Algorithm and approaches to handle large Data- A Survey

abstract:
  Data mining environment produces a large amount of data, that need to be
analyzed, patterns have to be extracted from that to gain knowledge. In this
new era with boom of data both structured and unstructured, in the field of
genomics, meteorology, biology, environmental research and many others, it has
become difficult to process, manage and analyze patterns using traditional
databases and architectures. So, a proper architecture should be understood to
gain knowledge about the Big Data. This paper presents a review of various
algorithms from 1994-2013 necessary for handling such large data set. These
algorithms define various structures and methods implemented to handle Big
Data, also in the paper are listed various tool that were developed for
analyzing them.


title:
Towards Distribution-Free Multi-Armed Bandits with Combinatorial
  Strategies

abstract:
  In this paper we study a generalized version of classical multi-armed bandits
(MABs) problem by allowing for arbitrary constraints on constituent bandits at
each decision point. The motivation of this study comes from many situations
that involve repeatedly making choices subject to arbitrary constraints in an
uncertain environment: for instance, regularly deciding which advertisements to
display online in order to gain high click-through-rate without knowing user
preferences, or what route to drive home each day under uncertain weather and
traffic conditions. Assume that there are $K$ unknown random variables (RVs),
i.e., arms, each evolving as an \emph{i.i.d} stochastic process over time. At
each decision epoch, we select a strategy, i.e., a subset of RVs, subject to
arbitrary constraints on constituent RVs.
  We then gain a reward that is a linear combination of observations on
selected RVs.
  The performance of prior results for this problem heavily depends on the
distribution of strategies generated by corresponding learning policy. For
example, if the reward-difference between the best and second best strategy
approaches zero, prior result may lead to arbitrarily large regret.
  Meanwhile, when there are exponential number of possible strategies at each
decision point, naive extension of a prior distribution-free policy would cause
poor performance in terms of regret, computation and space complexity.
  To this end, we propose an efficient Distribution-Free Learning (DFL) policy
that achieves zero regret, regardless of the probability distribution of the
resultant strategies.
  Our learning policy has both $O(K)$ time complexity and $O(K)$ space
complexity. In successive generations, we show that even if finding the optimal
strategy at each decision point is NP-hard, our policy still allows for
approximated solutions while retaining near zero-regret.


title:
Thermal and transport properties of a non-relativistic quantum gas
  interacting through a delta-shell potential

abstract:
  This work extends the seminal work of Gottfried on the two-body quantum
physics of particles interacting through a delta-shell potential to many-body
physics by studying a system of non-relativistic particles when the thermal
De-Broglie wavelength of a particle is smaller than the range of the potential
and the density is such that average distance between particles is smaller than
the range. The ability of the delta-shell potential to reproduce some basic
properties of the deuteron are examined. Relations for moments of bound states
are derived. The virial expansion is used to calculate the first quantum
correction to the ideal gas pressure in the form of the second virial
coefficient. Additionally, all thermodynamic functions are calculated up to the
first order quantum corrections. For small departures from equilibrium, the net
flows of mass, energy and momentum, characterized by the coefficients of
diffusion, thermal conductivity and shear viscosity, respectively, are
calculated. Properties of the gas are examined for various values of physical
parameters including the case of infinite scattering length when the unitary
limit is achieved.

categories: nucl-th cond-mat.quant-gas physics.atom-ph quant-ph


title: Tick Size Reduction and Price Clustering in a FX Order Book

abstract:
  We investigate the statistical properties of the EBS order book for the
EUR/USD and USD/JPY currency pairs and the impact of a ten-fold tick size
reduction on its dynamics. A large fraction of limit orders are still placed
right at or halfway between the old allowed prices. This generates price
barriers where the best quotes lie for much of the time, which causes the
emergence of distinct peaks in the average shape of the book at round
distances. Furthermore, we argue that this clustering is mainly due to manual
traders who remained set to the old price resolution. Automatic traders easily
take price priority by submitting limit orders one tick ahead of clusters, as
shown by the prominence of buy (sell) limit orders posted with rightmost digit
one (nine).


title: A class of exactly solvable models for the Schrodinger equation

abstract:
  We present a class of confining potentials which allow one to reduce the
one-dimensional Schroodinger equation to a named equation of mathematical
physics, namely either Bessel's or Whittaker's differential equation. In all
cases, we provide closed form expressions for both the symmetric and
antisymmetric wavefunction solutions, each along with an associated
transcendental equation for allowed eigenvalues. The class of potentials
considered contains an example of both cusp-like single wells and a
double-well.


title:
Reducing Electricity Demand Charge for Data Centers with Partial
  Execution

abstract:
  Data centers consume a large amount of energy and incur substantial
electricity cost. In this paper, we study the familiar problem of reducing data
center energy cost with two new perspectives. First, we find, through an
empirical study of contracts from electric utilities powering Google data
centers, that demand charge per kW for the maximum power used is a major
component of the total cost. Second, many services such as Web search tolerate
partial execution of the requests because the response quality is a concave
function of processing time. Data from Microsoft Bing search engine confirms
this observation.
  We propose a simple idea of using partial execution to reduce the peak power
demand and energy cost of data centers. We systematically study the problem of
scheduling partial execution with stringent SLAs on response quality. For a
single data center, we derive an optimal algorithm to solve the workload
scheduling problem. In the case of multiple geo-distributed data centers, the
demand of each data center is controlled by the request routing algorithm,
which makes the problem much more involved. We decouple the two aspects, and
develop a distributed optimization algorithm to solve the large-scale request
routing problem. Trace-driven simulations show that partial execution reduces
cost by $3\%--10.5\%$ for one data center, and by $15.5\%$ for geo-distributed
data centers together with request routing.


title: Electric and Magnetic fields due to Dirac particles in FRW spacetime

abstract:
  Some solutions of the Maxwell equations with Dirac particles for the source
in FRW spacetime are discussed. The Green's function of the equation for the
radial component of the Maxwell fields, F_{r\eta} and F_{\theta\phi} is solved.
Green's function is found to reduce to that of Minkowskian spacetime in the
appropriate limit. Also, the Lienard-Wiechert type solution is derived. Also,
the solutions with the Dirac particle current is also presented. It is found
that the F_{r\eta} is composed of even angular momentum states while the odd
states constitue F_{\theta\phi} .


title: P-wave Superfluidity by Blockade Effects in a Rydberg-Dressed Fermi Gas

abstract:
  We systematically investigate the p-wave superfluidity of a Rydberg-dressed
Fermi gas, where the soft-core effective interaction is of finite radius
$R_{c}$ due to blockade effects. After solving the BCS gap equation and
comparing the free energy, we obtain the quantum phase diagram, which is
composed of three different phases: polar ($p_{z}$), axial ($p_{x}+ip_{y}$),
and axi-planar ($p_{x}+i\beta_{p}p_{y}$) phases. The tri-critical point locates
around $R_{c}k_{F}\sim1$, where $k_{F}$ is the Fermi wave vector. We further
derive the Ginzburg-Landau theory to explain the phase diagram, and estimate
the transition temperature to be about 0.1$E_{F}$ in the current experimental
regime of $^{6}$Li. Our work paves the way for future studies on p-wave
superfluids and related quantum phase transitions in ultracold atoms.


title:
Realization of BEC-BCS crossover physics in a compact oven-loaded
  magneto-optic trap apparatus

abstract:
  We report on a simple oven-loaded magneto-optical trap (MOT) apparatus for
the creation of both molecular Bose-Einstein condensates (mBEC) and degenerate
Fermi gases (DFGs) of lithium. The apparatus does not require a Zeeman slower
or a 2D MOT nor does it require any separation or differential pumping between
the effusive atom source and the science chamber. The result is an exceedingly
simple, inexpensive, and compact vacuum system ideal for miniaturization. We
discuss our work in the context of other realizations of quantum degenerate
gases by evaporation in optical dipole traps and illustrate that our apparatus
meets the key requirements of atom number and trap lifetime. We also
demonstrate with this system the production of a mBEC, and we use it to observe
the pairing gap of a strongly interacting two-component DFG in the BEC-BCS
crossover regime.


title:
Leakage Current of a Superconductor-Normal Metal Tunnel Junction
  Connected to a High-Temperature Environment

abstract:
  We consider a voltage-biased Normal metal-Insulator-Superconductor (NIS)
tunnel junction, connected to a high-temperature external electromagnetic
environment. This model system features the commonly observed subgap leakage
current in NIS junctions through photon-assisted tunneling which is detrimental
for applications. We first consider a NIS junction directly coupled to the
environment and analyze the subgap leakage current both analytically and
numerically; we discuss the link with the phenomenological Dynes parameter.
Then we focus on a circuit where a low-temperature lossy transmission line is
inserted between the NIS junction and the environment. We show that the subgap
leakage current is exponentially suppressed as the length, $\ell$, and the
resistance per unit length, $R_0$, of the line are increased. We finally
discuss our results in view of the performance of NIS junctions in
applications.


title: On the Dirichlet and Neumann evolution operators in R^d_+

abstract:
  We prove some uniform and pointwise gradient estimates for the Dirichlet and
the Neumann evolution operators $G_{\mathcal{D}}(t,s)$ and
$G_{\mathcal{N}}(t,s)$ associated with a class of nonautonomous elliptic
operators $\A(t)$ with unbounded coefficients defined in $I\times \Rd_+$ (where
$I$ is a right-halfline or $I=\R$). We also prove the existence and the
uniqueness of a tight evolution system of measures $\{\mu_t^{\mathcal{N}}\}_{t
\in I}$ associated with $G_{\mathcal{N}}(t,s)$, which turns out to be
sub-invariant for $G_{\mathcal{D}}(t,s)$, and we study the asymptotic behaviour
of the evolution operators $G_{\mathcal{D}}(t,s)$ and $G_{\mathcal{N}}(t,s)$ in
the $L^p$-spaces related to the system $\{\mu_t^{\mathcal{N}}\}_{t \in I}$.


title: Software Carpentry: Lessons Learned

abstract:
  Over the last 15 years, Software Carpentry has evolved from a week-long
training course at the US national laboratories into a worldwide volunteer
effort to raise standards in scientific computing. This article explains what
we have learned along the way the challenges we now face, and our plans for the
future.


title: Non-stationary Stochastic Optimization

abstract:
  We consider a non-stationary variant of a sequential stochastic optimization
problem, in which the underlying cost functions may change along the horizon.
We propose a measure, termed variation budget, that controls the extent of said
change, and study how restrictions on this budget impact achievable
performance. We identify sharp conditions under which it is possible to achieve
long-run-average optimality and more refined performance measures such as rate
optimality that fully characterize the complexity of such problems. In doing
so, we also establish a strong connection between two rather disparate strands
of literature: adversarial online convex optimization; and the more traditional
stochastic approximation paradigm (couched in a non-stationary setting). This
connection is the key to deriving well performing policies in the latter, by
leveraging structure of optimal policies in the former. Finally, tight bounds
on the minimax regret allow us to quantify the "price of non-stationarity,"
which mathematically captures the added complexity embedded in a temporally
changing environment versus a stationary one.


title: Chemical Kinetics on Extrasolar Planets

abstract:
  Chemical kinetics plays an important role in controlling the atmospheric
composition of all planetary atmospheres, including those of extrasolar
planets. For the hottest exoplanets, the composition can closely follow
thermochemical-equilibrium predictions, at least in the visible and infrared
photosphere at dayside (eclipse) conditions. However, for atmospheric
temperatures < ~2000 K, and in the uppermost atmosphere at any temperature,
chemical kinetics matters. The two key mechanisms by which kinetic processes
drive an exoplanet atmosphere out of equilibrium are photochemistry and
transport-induced quenching. We review these disequilibrium processes in
detail, discuss observational consequences, and examine some of the current
evidence for kinetic processes on extrasolar planets.


title:
Stone-Wales Defects in Silicene: Formation, Stability and Reactivity of
  Defect Sites

abstract:
  During the synthesis of ultra-thin materials with hexagonal lattice structure
Stone-Wales (SW) type of defects are quite likely to be formed and the
existence of such topological defects in the graphene-like structures results
in dramatical changes of their electronic and mechanical properties. Here we
investigate the formation and reactivity of such SW defects in silicene. We
report the energy barrier for the formation of SW defects in freestanding (~2.4
eV) and Ag(111)-supported (~2.8 eV) silicene and found it to be significantly
lower than in graphene (~9.2 eV). Moreover, the buckled nature of silicene
provides a large energy barrier for the healing of the SW defect and therefore
defective silicene is stable even at high temperatures. Silicene with SW
defects is semiconducting with a direct bandgap of 0.02 eV and this value
depends on the concentration of defects. Furthermore, nitrogen substitution in
SW defected silicene shows that the defect lattice sites are the least
preferable substitution locations for the N atoms. Our findings show the easy
formation of SW defects in silicene and also provide a guideline for bandgap
engineering in silicene-based materials through such defects.


title:
Chimera states in networks of nonlocally coupled Hindmarsh-Rose neuron
  models

abstract:
  We have identified the occurrence of chimera states for various coupling
schemes in networks of two-dimensional and three-dimensional Hindmarsh-Rose
oscillators, which represent realistic models of neuronal ensembles. This
result, together with recent studies on multiple chimera states in nonlocally
coupled FitzHugh-Nagumo oscillators, provide strong evidence that the
phenomenon of chimeras may indeed be relevant in neuroscience applications.
Moreover, our work verifies the existence of chimera states in coupled bistable
elements, whereas to date chimeras were known to arise in models possessing a
single stable limit cycle. Finally, we have identified an interesting class of
mixed oscillatory states, in which desynchronized neurons are uniformly
interspersed among the remaining ones that are either stationary or oscillate
in synchronized motion.


title: An areal analog of Mahler's measure

abstract:
  We consider a version of height on polynomial spaces defined by the integral
over the normalized area measure on the unit disk. This natural analog of
Mahler's measure arises in connection with extremal problems for Bergman
spaces. It inherits many nice properties such as the multiplicative one.
However, this height is a lower bound for Mahler's measure, and it can be
substantially lower. We discuss some similarities and differences between the
two.


title: Weighted energy problem on the unit circle

abstract:
  We solve the weighted energy problem on the unit circle, by finding the
extremal measure and describing its support. Applications to polynomial and
exponential weights are also included.


title: Inequalities for products of polynomials I

abstract:
  We study inequalities connecting the product of uniform norms of polynomials
with the norm of their product. This circle of problems include the
Gelfond-Mahler inequality for the unit disk and the Kneser-Borwein inequality
for the segment $[-1,1]$. Furthermore, the asymptotically sharp constants are
known for such inequalities over arbitrary compact sets in the complex plane.
It is shown here that this best constant is smallest (namely: 2) for a disk. We
also conjecture that it takes its largest value for a segment, among all
compact connected sets in the plane.


abstract:
  The multivariate integer Chebyshev problem is to find polynomials with
integer coefficients that minimize the supremum norm over a compact set in
$\C^d.$ We study this problem on general sets, but devote special attention to
product sets such as cube and polydisk. We also establish a multivariate analog
of the Hilbert-Fekete upper bound for the integer Chebyshev constant, which
depends on the dimension of space. In the case of single variable polynomials
in the complex plane, our estimate coincides with the Hilbert-Fekete result.


title: How to find a measure from its potential

abstract:
  We consider the problem of finding a measure from the given values of its
logarithmic potential on the support. It is well known that a solution to this
problem is given by the generalized Laplacian. The case of our main interest is
when the support is contained in a rectifiable curve, and the measure is
absolutely continuous with respect to the arclength on this curve. Then the
generalized Laplacian is expressed by a sum of normal derivatives of the
potential. Such representation was available for smooth curves, and we show it
holds for any rectifiable curve in the plane. We also relax the assumptions
imposed on the potential.
  Finding a measure from its potential often leads to another closely related
problem of solving a singular integral equation with Cauchy kernel. The theory
of such equations is well developed for smooth curves. We generalize this
theory to the class of Ahlfors regular curves and arcs, and characterize the
bounded solutions on arcs.


title:
Implication of neutrino backgrounds on the reach of next generation dark
  matter direct detection experiments

abstract:
  As direct dark matter experiments continue to increase in size, they will
become sensitive to neutrinos from astrophysical sources. For experiments that
do not have directional sensitivity, coherent neutrino scattering (CNS) from
several sources represents an important background to understand, as it can
almost perfectly mimic an authentic WIMP signal. Here we explore in detail the
effect of neutrino backgrounds on the discovery potential of WIMPs over the
entire mass range of 500 MeV to 10 TeV. We show that, given the theoretical and
measured uncertainties on the neutrino backgrounds, direct detection
experiments lose sensitivity to light (~10 GeV) and heavy (~100 GeV) WIMPs with
a spin-independent cross section below 10^{-45} cm^2 and 10^{-49} cm^2,
respectively.


title: Convex Clustering via Optimal Mass Transport

abstract:
  We consider approximating distributions within the framework of optimal mass
transport and specialize to the problem of clustering data sets. Distances
between distributions are measured in the Wasserstein metric. The main problem
we consider is that of approximating sample distributions by ones with sparse
support. This provides a new viewpoint to clustering. We propose different
relaxations of a cardinality function which penalizes the size of the support
set. We establish that a certain relaxation provides the tightest convex lower
approximation to the cardinality penalty. We compare the performance of
alternative relaxations on a numerical study on clustering.


title:
Eigenfunction expansions associated with operator differential equation
  depending on spectral parameter nonlinearly

abstract:
  For operator differential equation which depends on the spectral parameter in
the Nevanlinna manner we obtain the expansions in eigenfunctions.


title:
Quantum hyperbolic geometry in loop quantum gravity with cosmological
  constant

abstract:
  Loop Quantum Gravity (LQG) is an attempt to describe the quantum gravity
regime. Introducing a non-zero cosmological constant $\Lambda$ in this context
has been a withstanding problem. Other approaches, such as Chern-Simons
gravity, suggest that quantum groups can be used to introduce $\Lambda$ in the
game. Not much is known when defining LQG with a quantum group. Tensor
operators can be used to construct observables in any type of discrete quantum
gauge theory with a classical/quantum gauge group. We illustrate this by
constructing explicitly geometric observables for LQG defined with a quantum
group and show for the first time that they encode a quantized hyperbolic
geometry. This is a novel argument pointing out the usefulness of quantum
groups as encoding a non-zero cosmological constant. We conclude by discussing
how tensor operators provide the right formalism to unlock the LQG formulation
with a non-zero cosmological constant.


title: Demonstration of active routing of entanglement in a multi-user network

abstract:
  We implement an entanglement distribution network based on
wavelength-multiplexing and optical switching for quantum communication
applications. Using a high-brightness source based on spontaneous parametric
down-conversion in periodically-poled lithium niobate waveguides, we generate
polarisation entangled photon pairs with a broad spectrum covering the telecom
wavelengths around 1550nm. The photon pairs have entanglement fidelities up to
99%, and are distributed via passive wavelength multiplexing in a static
multi-user network. We furthermore demonstrate a possible network application
in a scenario with a single centralised source dynamically allocating two-party
entanglement to any pair of users by means of optical switches. The whole
system, from the pump laser up to the receivers, is fibre and waveguide based,
resulting in maximal stability, minimal losses and the advantage of readily
integrable telecom components in the 1550nm range.


title: Novel Photo Multiplier Tubes for the Cherenkov Telescope Array Project

abstract:
  Currently the standard light sensors for imaging atmospheric Cherenkov
telescopes are the classical photo multiplier tubes that are using bialkali
photo cathodes. About eight years ago we initiated an improvement program with
the Photo Multiplier Tube (PMT) manufacturers Hamamatsu (Japan), Electron Tubes
Enterprises (England) and Photonis (France) for the needs of imaging
atmospheric Cherenkov telescopes. As a result, after about 40 years of
stagnation of the peak Quantum Efficiency (QE) on the level of 25-27%, new PMTs
appeared with a peak QE of 35%. These have got the name super-bialkali. The
second significant upgrade has happened very recently, as a result of a
dedicated improvement program for the candidate PMT for Cherenkov Telescope
Array. The latter is going to be the next generation major instrument in the
field of very high energy gamma astrophysics and will consist of over 100
telescopes of three different sizes of 23m, 12m and 4-7m, located both in
southern and northern hemispheres. Now PMTs with average peak QE of
approximately 40% became available. Also, the photo electron collection
efficiency of the previous generation PMTs of 80- 90% has been enhanced towards
95-98% for the new ones. The after-pulsing of novel PMTs has been reduced
towards the level of 0.02% for the set threshold of 4 photo electrons. We will
report on the PMT development work by the companies Electron Tubes Enterprises
and Hamamatsu Photonics K.K. show the achieved results and the current status.


title: Magnetic properties of Sn/1-x/Cr/x/Te diluted magnetic semiconductors

abstract:
  We present the studies of Sn/1-x/Cr/x/Te semimagnetic semiconductors with
chemical composition x ranging from 0.004 to 0.012. The structural
characterization indicates that even at low average Cr-content x < ?0.012, the
aggregation into micrometer size clusters appears in our samples. The magnetic
properties are affected by the presence of clusters. In all our samples we
observe the transition into the ordered state at temperatures between 130 and
140 K. The analysis of both static and dynamic magnetic susceptibility data
indicates that the spin-glass-like state is observed in our samples. The
addition of Cr to the alloy seems to shift the spin-glass-like transition from
130 K for x = 0.004 to 140 K for x = 0.012.


title:
Light Trapping Textures Designed by Electromagnetic Optimization for
  Sub-Wavelength Thick Solar Cells

abstract:
  Light trapping in solar cells allows for increased current and voltage, as
well as reduced materials cost. It is known that in geometrical optics, a
maximum 4n^2 absorption enhancement factor can be achieved by randomly
texturing the surface of the solar cell, where n is the material refractive
index. This ray-optics absorption enhancement limit only holds when the
thickness of the solar cell is much greater than the optical wavelength. In
sub-wavelength thin films, the fundamental questions remain unanswered: (1)
what is the sub-wavelength absorption enhancement limit and (2) what surface
texture realizes this optimal absorption enhancement? We turn to computational
electromagnetic optimization in order to design nanoscale textures for light
trapping in sub-wavelength thin films. For high-index thin films, in the weakly
absorbing limit, our optimized surface textures yield an angle- and
frequency-averaged enhancement factor ~39. They perform roughly 30% better than
randomly textured structures, but they fall short of the ray optics enhancement
limit of 4n^2 ~ 50.


title:
Compactness in quasi-Banach function spaces and applications to compact
  embeddings of Besov-type spaces

abstract:
  There are two main aims of the paper. The first one is to extend the
criterion for the precompactness of sets in Banach function spaces to the
setting of quasi-Banach function spaces. The second one is to extend the
criterion for the precompactness of sets in the Lebesgue spaces $L_p(\mathbb
R^n)$, $1 \leq p < \infty$, to the so-called power quasi-Banach function
spaces. These criteria are applied to establish compact embeddings of abstract
Besov spaces into quasi-Banach function spaces. The results are illustrated on
embeddings of Besov spaces $B^s_{p,q}(\mathbb R^n)$, $0<s<1$, $0<p,q\leq
\infty$, into Lorentz-type spaces.


title:
Balanced line bundles and equivariant compactifications of homogeneous
  spaces

abstract:
  Manin's conjecture predicts an asymptotic formula for the number of rational
points of bounded height on a smooth projective variety in terms of its global
geometric invariants. The strongest form of the conjecture implies certain
inequalities among geometric invariants of the variety and of its subvarieties.
We provide a general geometric framework explaining these phenomena, via the
notion of balanced line bundles, and prove the required inequalities for a
large class of equivariant compactifications of homogeneous spaces.


title: Urea-induced denaturation of PreQ1-riboswitch

abstract:
  Urea, a polar molecule with a large dipole moment, not only destabilizes the
folded RNA structures, but can also enhance the folding rates of large
ribozymes. Unlike the mechanism of urea-induced unfolding of proteins, which is
well understood, the action of urea on RNA has barely been explored. We
performed extensive all atom molecular dynamics (MD) simulations to determine
the molecular underpinnings of urea-induced RNA denaturation. Urea displays its
denaturing power in both secondary and tertiary motifs of the riboswitch (RS)
structure. Our simulations reveal that the denaturation of RNA structures is
mainly driven by the hydrogen bonds and stacking interactions of urea with the
bases. Through detailed studies of the simulation trajectories, we found that
geminate pairs between urea and bases due to hydrogen bonds and stacks persist
only ~ (0.1-1) ns, which suggests that urea-base interaction is highly dynamic.
Most importantly, the early stage of base pair disruption is triggered by
penetration of water molecules into the hydrophobic domain between the RNA
bases. The infiltration of water into the narrow space between base pairs is
critical in increasing the accessibility of urea to transiently disrupted
bases, thus allowing urea to displace inter base hydrogen bonds. This
mechanism, water-induced disruption of base-pairs resulting in the formation of
a "wet" destabilized RNA followed by solvation by urea, is the exact opposite
of the two-stage denaturation of proteins by urea. In the latter case, initial
urea penetration creates a dry-globule, which is subsequently solvated by water
penetration leading to global protein unfolding. Our work shows that the
ability to interact with both water and polar, non-polar components of
nucleotides makes urea a powerful chemical denaturant for nucleic acids.


title:
De Sitter Universe from Causal Dynamical Triangulations without
  Preferred Foliation

abstract:
  We present a detailed analysis of a recently introduced version of Causal
Dynamical Triangulations (CDT) that does not rely on a distinguished time
slicing. Focussing on the case of 2+1 spacetime dimensions, we analyze its
geometric and causal properties, present details of the numerical set-up and
explain how to extract "volume profiles". Extensive Monte Carlo measurements of
the system show the emergence of a de Sitter universe on large scales from the
underlying quantum ensemble, similar to what was observed previously in
standard CDT quantum gravity. This provides evidence that the distinguished
time slicing of the latter is not an essential part of its kinematical set-up.


title: Spin Precession in Inertial and Gravitational Fields

abstract:
  We discuss the motion of spin in inertial and gravitational fields. The
coupling of spin with rotation and the gravitomagnetic field has already been
extensively studied; therefore, we focus here on the inertial and gravitational
spin-orbit couplings. In particular, we investigate the classical and quantum
aspects of spin precession and spin-orbit coupling in an arbitrary
translationally accelerated frame of reference as well as the exterior
Schwarzschild spacetime. Moreover, in connection with Einstein's principle of
equivalence, we clarify the relation between the inertial and gravitational
spin-orbit couplings.


title: Mean Dimension, Mean Rank, and von Neumann-L\"uck Rank

abstract:
  We introduce an invariant, called mean rank, for any module M of the integral
group ring of a discrete amenable group $\Gamma$, as an analogue of the rank of
an abelian group. It is shown that the mean dimension of the induced
$\Gamma$-action on the Pontryagin dual of M, the mean rank of M, and the von
Neumann-L\"uck rank of M all coincide.
  As applications, we establish an addition formula for mean dimension of
algebraic actions, prove the analogue of the Pontryagin-Schnirelmnn theorem for
algebraic actions, and show that for elementary amenable groups with an upper
bound on the orders of finite subgroups, algebraic actions with zero mean
dimension are inverse limits of finite entropy actions.


title:
Visualization of superposition states and Raman processes with
  two-dimensional atomic deflection

abstract:
  Deflection of atoms in \Lambda-type configuration passing through two crossed
standing light waves is proposed for probing and visualization of atomic
superposition states. For this goal, we use both the large-dispersive and
Raman-resonant regimes of atom-field interaction giving rise to a
position-dependent phase shifts of fields and perform double simultaneous
spatial measurements on an atom. In this way, it is demonstrated that the
deflection spatial patterns of atoms in \Lambda-configuration passing through
modes of standing waves are essentially modified if the atoms are initially
prepared in a coherent superposition of its low levels states as well as when
the superposition states are created during the process of deflection. The
similar results take place for the joint momentum distribution of atoms.
Further, considering both one-photon and two-photon excitation regimes of
\Lambda-atoms we also illustrate that the two-dimensional patterns of defected
atoms qualitatively reflects the efficiency of the Raman processes.


title: Hodge theory on Cheeger spaces

abstract:
  We extend the study of the de Rham operator with ideal boundary conditions
from the case of isolated conic singularities, as analyzed by Cheeger, to the
case of arbitrary stratified pseudomanifolds. We introduce a class of ideal
boundary operators and the notion of mezzoperversity, which intermediates
between the standard lower and upper middle perversities in intersection
theory, as interpreted in this de Rham setting, and show that the de Rham
operator with these boundary conditions is Fredholm and has compact resolvent.
We also prove an isomorphism between the resulting Hodge and L2 de Rham
cohomology groups, and that these are independent of the choice of iterated
edge metric. On spaces which admit ideal boundary conditions of this type which
are also self-dual, which we call `Cheeger spaces', we show that these Hodge/de
Rham cohomology groups satisfy Poincare Duality.


title: Inhomogeneous self-affine carpets

abstract:
  We investigate the dimension theory of inhomogeneous self-affine carpets.
Through the work of Olsen, Snigireva and Fraser, the dimension theory of
inhomogeneous self-similar sets is now relatively well-understood, however,
almost no progress has been made concerning more general non-conformal
inhomogeneous attractors. If a dimension is countably stable, then the results
are immediate and so we focus on the upper and lower box dimensions and compute
these explicitly for large classes of inhomogeneous self-affine carpets.
Interestingly, we find that the `expected formula' for the upper box dimension
can fail in the self-affine setting and we thus reveal new phenomena, not
occurring in the simpler self-similar case.


title:
Emergent Spin-Filter at the interface between Ferromagnetic and
  Insulating Layered Oxides

abstract:
  We report a strong effect of interface-induced magnetization on the transport
properties of magnetic tunnel junctions consisting of ferromagnetic manganite
La$_{0.7}$Ca$_{0.3}$MnO$_{3}$ and insulating cuprate PrBa$_{2}$Cu$_{3}$O$_{7}$.
Contrary to the typically observed steady increase of the tunnel
magnetoresistance with decreasing temperature, this system exhibits a sudden
anomalous decrease at low temperatures. Interestingly, this anomalous behavior
can be attributed to the competition between the positive spin polarization of
the manganite contacts and the negative spin-filter effect from the
interface-induced Cu magnetization.


title:
Bootstrapped Pivots for Sample and Population Means and Distribution
  Functions

abstract:
  In this paper we introduce the concept of bootstrapped pivots for the sample
and the population means. This is in contrast to the classical method of
constructing bootstrapped confidence intervals for the population mean via
estimating the cutoff points via drawing a number of bootstrap sub-samples. We
show that this new method leads to constructing asymptotic confidence intervals
with significantly smaller error in comparison to both of the traditional
t-intervals and the classical bootstrapped confidence intervals. The approach
taken in this paper relates naturally to super-population modeling, as well as
to estimating empirical and theoretical distributions.


title:
Diffuse Interstellar Bands: How Are They Related to Known Gas-Phase
  Constituents of the ISM?

abstract:
  In this brief review of recent work relating the DIBs to other gas-phase
constituents of the ISM, we explore correlations between DIB equivalent widths
and the column densities of various atomic and molecular species, drawn from a
large database constructed for that purpose. The tightness and slopes of the
correlations can provide information on how the DIBs might be related to those
species (physically, chemically, spatially) and on various properties of the
DIB carriers. Deviations from the mean relationships can reveal dependences of
DIB strengths on other parameters, regional variations in DIB behavior, and
individual sight lines where unusual environmental conditions affect the DIBs.
Variations in DIB profiles (e.g., wings, substructure) and relative strengths
may be related to differences in physical conditions inferred from atomic
and/or molecular absorption lines.


title:
Observability and Controllability of Nonlinear Networks: The Role of
  Symmetry

abstract:
  Observability and controllability are essential concepts to the design of
predictive observer models and feedback controllers of networked systems. For
example, noncontrollable mathematical models of real systems have subspaces
that influence model behavior, but cannot be controlled by an input. Such
subspaces can be difficult to determine in complex nonlinear networks. Since
almost all of the present theory was developed for linear networks without
symmetries, here we present a numerical and group representational framework,
to quantify the observability and controllability of nonlinear networks with
explicit symmetries that shows the connection between symmetries and nonlinear
measures of observability and controllability. We numerically observe and
theoretically predict that not all symmetries have the same effect on network
observation and control. Our analysis shows that the presence of symmetry in a
network may decrease observability and controllability, although networks
containing only rotational symmetries remain controllable and observable. These
results alter our view of the nature of observability and controllability in
complex networks, change our understanding of structural controllability, and
affect the design of mathematical models to observe and control such networks.


title:
Orbital, Superhump, and Superorbital Periods in the Cataclysmic
  Variables AQ Mensae and IM Eridani

abstract:
  We report photometric detections of orbital and superorbital signals, and
negative orbital sidebands, in the light curves of the nova-like cataclysmic
variables AQ Mensae and IM Eridani. The frequencies of the orbital,
superorbital, and sideband signals are 7.0686 (3), 0.263 (3), and 7.332 (3)
cycles per day (c/d) in AQ Mensae, and 6.870 (1), 0.354 (7), and 7.226 (1) c/d
in IM Eridani. We also find a spectroscopic orbital frequency in IM Eridani of
6.86649 (2) c/d. These observations can be reproduced by invoking an accretion
disc that is tilted with respect to the orbital plane. This model works well
for X-ray binaries, in which irradiation by a primary neutron star can account
for the disc's tilt. A likely tilt mechanism has yet to be identified in CVs,
yet the growing collection of observational evidence indicates that the
phenomenon of tilt is indeed at work in this class of object. The results
presented in this paper bring the number of CVs known to display signals
associated with retrograde disc precession to twelve.
  We also find AQ Mensae to be an eclipsing system. The eclipse depths are
highly variable, which suggests that the eclipses are grazing. This finding
raises the possibility of probing variations in disc tilt by studying
systematic variations in the eclipse profile.


title:
The Vela-X Pulsar Wind Nebula revisited with 4 years of Fermi-Large Area
  Telescope observations

abstract:
  The Vela supernova remnant is the closest supernova remnant to Earth
containing an active pulsar, the Vela pulsar (PSR B0833-45). This pulsar is the
archetype of the middle-aged pulsar class and powers a bright pulsar wind
nebula (PWN), Vela-X, spanning a region of 2{\deg} x 3{\deg} south of the
pulsar and observed in the radio, X-ray and very high energy gamma-ray domains.
The detection of the Vela-X PWN by the Fermi Large Area Telescope (LAT) was
reported in the first year of the mission. Subsequently, we have
re-investigated this complex region and performed a detailed morphological and
spectral analysis of this source using 4 years of Fermi-LAT observations. This
study lowers the threshold for morphological analysis of the nebula from 0.8
GeV to 0.3 GeV, allowing inspection of distinct energy bands by the LAT for the
first time. We describe the recent results obtained on this PWN and discuss the
origin of the newly detected spatial features.


title: Cesaro-Hardy operators on bilateral grand Lebesgue spaces

abstract:
  We obtain in this short article the non-asymptotic estimations for the norm
of (generalized) Cesaro-Hardy integral operators in the so-called Bilateral
Grand Lebesgue Spaces. We also give examples to show the sharpness of these
inequalities.


title: Classification topologique des solutions du Probl\`eme d'Apollonius

abstract:
  We give a mathematical computation of the number of solutions of Apollonius
problem, by use of Lie Sphere Geometry. Unlike in higher dimensions, the number
of solutions depends only on the topology of the configuration of the 3
objects. It appears that our classification is non redundant, and far simpler
than those obtained previously.


title:
Approaching Gaussian Relay Network Capacity in the High SNR Regime:
  End-to-End Lattice Codes

abstract:
  We present a natural and low-complexity technique for achieving the capacity
of the Gaussian relay network in the high SNR regime. Specifically, we propose
the use of end-to-end structured lattice codes with the amplify-and-forward
strategy, where the source uses a nested lattice code to encode the messages
and the destination decodes the messages by lattice decoding. All intermediate
relays simply amplify and forward the received signals over the network to the
destination. We show that the end-to-end lattice-coded amplify-and-forward
scheme approaches the capacity of the layered Gaussian relay network in the
high SNR regime. Next, we extend our scheme to non-layered Gaussian relay
networks under the amplify-and-forward scheme, which can be viewed as a
Gaussian intersymbol interference (ISI) channel. Compared with other schemes,
our approach is significantly simpler and requires only the end-to-end design
of the lattice precoding and decoding. It does not require any knowledge of the
network topology or the individual channel gains.


title: Geometric constructibility of cyclic polygons and a limit theorem

abstract:
  We study convex cyclic polygons, that is, inscribed $n$-gons. Starting from
P. Schreiber's idea, published in 1993, we prove that these polygons are not
constructible from their side lengths with straightedge and compass, provided
$n$ is at least five. They are non-constructible even in the particular case
where they only have two different integer side lengths, provided that $n\neq
6$. To achieve this goal, we develop two tools of separate interest. First, we
prove a limit theorem stating that, under reasonable conditions, geometric
constructibility is preserved under taking limits. To do so, we tailor a
particular case of Puiseux's classical theorem on some generalized power
series, called Puiseux series, over algebraically closed fields to an analogous
theorem on these series over real square root closed fields. Second, based on
Hilbert's irreducibility theorem, we give a \emph{rational parameter theorem}
that, under reasonable conditions again, turns a non-constructibility result
with a transcendental parameter into a non-constructibility result with a
rational parameter. For $n$ even and at least six, we give an elementary proof
for the non-constructibility of the cyclic $n$-gon from its side lengths and,
also, from the \emph{distances} of its sides from the center of the
circumscribed circle. The fact that the cyclic $n$-gon is constructible from
these distances for $n=4$ but non-constructible for $n=3$ exemplifies that some
conditions of the limit theorem cannot be omitted.


title:
Tunneling Tuned Spin Modulations in Ultrathin Topological Insulator
  Films

abstract:
  Quantitative understanding of the relationship between quantum tunneling and
Fermi surface spin polarization is key to device design using topological
insulator surface states. By using spin-resolved photoemission spectroscopy
with p-polarized light in topological insulator Bi2Se3 thin films across the
metal-to-insulator transition, we observe that for a given film thickness, the
spin polarization is large for momenta far from the center of the surface
Brillouin zone. In addition, the polarization decreases significantly with
enhanced tunneling realized systematically in thin insulating films, whereas
magnitude of the polarization saturates to the bulk limit faster at larger
wavevectors in thicker metallic films. Our theoretical model calculations
capture this delicate relationship between quantum tunneling and Fermi surface
spin polarization. Our results suggest that the polarization current can be
tuned to zero in thin insulating films forming the basis for a future
spin-switch nano-device.


title:
KATRIN: an experiment to determine the neutrino mass from the beta decay
  of tritium

abstract:
  KATRIN is a very large scale tritium-beta-decay experiment to determine the
mass of the neutrino. It is presently under construction at the Karlsruhe
Institute of Technology north campus, and makes use of the Karlsruhe Tritium
Laboratory built as a prototype for the ITER project. The combination of a
large retarding-potential electrostatic-magnetic spectrometer and an intense
gaseous molecular tritium source makes possible a sensitivity to neutrino mass
of 0.2 eV, about an order of magnitude below present laboratory limits. The
measurement is kinematic and independent of whether the neutrino is Dirac or
Majorana. The status of the project is summarized briefly in this report.


title: White Paper: Measuring the Neutrino Mass Hierarchy

abstract:
  This white paper is a condensation of a report by a committee appointed
jointly by the Nuclear Science and Physics Divisions at Lawrence Berkeley
National Laboratory (LBNL). The goal of this study was to identify the most
promising technique(s) for resolving the neutrino mass hierarchy. For the most
part, we have relied on calculations and simulations presented by the
proponents of the various experiments. We have included evaluations of the
opportunities and challenges for these experiments based on what is available
already in the literature.


title: Spatiotemporal buildup of the Kondo screening cloud

abstract:
  We investigate how the Kondo screening cloud builds up as a function of space
and time. Starting from an impurity spin decoupled from the conduction band,
the Kondo coupling is switched on at time t=0. We work at the Toulouse point
where one can obtain exact analytical results for the ensuing spin dynamics at
both zero and nonzero temperature T. For t>0 the Kondo screening cloud starts
building up in the wake of the impurity spin being transported to infinity. In
this buildup process the impurity spin--conduction band spin susceptibility
shows a sharp light cone due to causality, while the corresponding correlation
function has a tail outside the light cone. At T=0 this tail has a power law
decay as a function of distance from the impurity, which we interpret as due to
initial entanglement in the Fermi sea.


title: Theory of Native Orientational Pinning in Quantum Hall Nematics

abstract:
  The orientation of the electron-nematic states discovered in the quantum Hall
regime of GaAs $[001]$ growth-direction quantum wells is pinned by a weak
native source of anisotropy. In this Letter we explain that this property,
which has remained mysterious over more than a decade of research, follows from
the presence of both Rashba and Dresselhaus spin-orbit interactions. The hard
transport direction of the nematic state is determined by the relative sign of
the Rashba and Dresselhaus coefficients, and coincides with either the $[110]$
or the $[1\bar{1}0]$ crystallographic direction. Our theoretical estimate of
the pinning energy is in agreement with experimental studies of the competition
between native pinning and intentional pinning by an in-plane magnetic field.


title:
Birational automorphism groups of projective varieties of Picard number
  two

abstract:
  We slightly extend a result of Oguiso on birational or automorphism groups
(resp. of Lazi\'c - Peternell on Morrison-Kawamata cone conjecture) from
Calabi-Yau manifolds of Picard number two to arbitrary singular varieties X
(resp. to klt Calabi-Yau pairs in broad sense) of Picard number two. When X has
only klt singularities and is not a complex torus, we show that either Aut(X)
is almost cyclic, or it has only finitely many connected components.


title: Traveling Wave Solutions of Competitive Models with Free Boundaries

abstract:
  We study two systems of reaction diffusion equations with monostable or
bistable type of nonlinearity and with free boundaries. These systems are used
as multi-species competitive model. For two-species models, we prove the
existence of a traveling wave solution which consists of two semi-waves
intersecting at the free boundary. For three-species models, we also prove the
existence of a traveling wave solution which, however, consists of two
semi-waves and one compactly supported wave in between, each intersecting with
its neighbor at the free boundary.


title: The Study of Rare $B_c\rightarrow D^{(*)}_{s,d}l\bar{l}$ Decays

abstract:
  In this paper, we study rare decays $B_c\rightarrow D^{(*)}_{s,d}l\bar{l}$
within the Standard Model. The penguin, box, annihilation, color-favored
cascade and color-suppressed cascade contributions are included. Based on our
calculation, the annihilation and color-favored cascade diagrams play important
roles in the differential branching fractions, forward-backward asymmetries,
longitudinal polarizations of the final vector mesons and leptonic longitudinal
polarization asymmetries. More importantly, color-favored cascade decays
largely enhance the resonance cascade contributions. To avoid the resonance
cascade contribution pollution, new cutting regions are put forward.


title: Ehrhart polynomials and symplectic embeddings of ellipsoids

abstract:
  McDuff and Schlenk determined when a four-dimensional ellipsoid can be
symplectically embedded into a ball, and found that part of the answer is given
by an infinite "Fibonacci staircase." Similarly, Frenkel and M\"uller
determined when a four-dimensional ellipsoid can be symplectically embedded
into the ellipsoid E(1,2) and found that part of the answer is given by a "Pell
staircase." ECH capacities give an obstruction to symplectically embedding one
four-dimensional ellipsoid into another, and McDuff showed that this
obstruction is sharp. We use this result to give new proofs of the staircases
of McDuff-Schlenk and Frenkel-M\"uller, and we prove that another infinite
staircase arises for embeddings into the ellipsoid E(1,3/2). Our proofs relate
these staircases to a combinatorial phenomenon of independent interest called
"period collapse" of the Ehrhart quasipolynomial.
  In the appendix, we use McDuff's theorem to show that for a >= 6, the only
obstruction to embedding an ellipsoid E(1,a) into a scaling of E(1,3/2) is the
volume, and we also give new proofs of similar results for embeddings into
scalings of E(1,1) and E(1,2).


title: On GROUSE and Incremental SVD

abstract:
  GROUSE (Grassmannian Rank-One Update Subspace Estimation) is an incremental
algorithm for identifying a subspace of Rn from a sequence of vectors in this
subspace, where only a subset of components of each vector is revealed at each
iteration. Recent analysis has shown that GROUSE converges locally at an
expected linear rate, under certain assumptions. GROUSE has a similar flavor to
the incremental singular value decomposition algorithm, which updates the SVD
of a matrix following addition of a single column. In this paper, we modify the
incremental SVD approach to handle missing data, and demonstrate that this
modified approach is equivalent to GROUSE, for a certain choice of an
algorithmic parameter.


title: Another Detector for the International Linear Collider

abstract:
  We describe another detectora designed for the International Linear Collider
based on several tested instrumentation innovations in order to achieve the
necessary experi- mental goal of a detecter that is 2-to-10 times better than
the already excellent SLC and LEP detectors, in particular, (1) dual-readout
calorimeter system based on the RD52/DREAM measurements at CERN, (2) a
cluster-counting drift chamber based on the successful kloe chamber at
Frascati, and (3) a second solenoid to return the magnetic flux without iron. A
high-performance pixel vertex chamber is presently undefined. We discuss
particle identification, momentum and energy resolutions, and the
machine-detector interface that together offer the possibility of a very
high-performance detector for $e^+e^-$physics up to $\sqrt{s} = 1$ TeV.


title: Astrophysical hydromagnetic turbulence

abstract:
  Recent progress in astrophysical hydromagnetic turbulence is being reviewed.
The physical ideas behind the now widely accepted Goldreich--Sridhar model and
its extension to compressible magnetohydrodynamic turbulence are introduced.
Implications for cosmic ray diffusion and acceleration is being discussed.
Dynamo-generated magnetic fields with and without helicity are contrasted
against each other. Certain turbulent transport processes are being modified
and often suppressed by anisotropy and inhomogeneities of the turbulence, while
others are being produced by such properties, which can lead to new large-scale
instabilities of the turbulent medium. Applications of various such processes
to astrophysical systems are being considered.


title:
A scalable stage-wise approach to large-margin multi-class loss based
  boosting

abstract:
  We present a scalable and effective classification model to train multi-class
boosting for multi-class classification problems. Shen and Hao introduced a
direct formulation of multi- class boosting in the sense that it directly
maximizes the multi- class margin [C. Shen and Z. Hao, "A direct formulation
for totally-corrective multi- class boosting", in Proc. IEEE Conf. Comp. Vis.
Patt. Recogn., 2011]. The major problem of their approach is its high
computational complexity for training, which hampers its application on
real-world problems. In this work, we propose a scalable and simple stage-wise
multi-class boosting method, which also directly maximizes the multi-class
margin. Our approach of- fers a few advantages: 1) it is simple and
computationally efficient to train. The approach can speed up the training time
by more than two orders of magnitude without sacrificing the classification
accuracy. 2) Like traditional AdaBoost, it is less sensitive to the choice of
parameters and empirically demonstrates excellent generalization performance.
Experimental results on challenging multi-class machine learning and vision
tasks demonstrate that the proposed approach substantially improves the
convergence rate and accuracy of the final visual detector at no additional
computational cost compared to existing multi-class boosting.


title:
Nilpotent and polycyclic-by-finite maximal subgroups of skew linear
  groups

abstract:
  Let D be an infinite division ring, n a natural number and N a subnormal
subgroup of GLn(D) such that n = 1 or the center of D contains at least five
elements. This paper contains two main results. In the first one we prove that
each nilpotent maximal subgroup of N is abelian; this generalizes the result in
[R. Ebrahimian, J. Algebra 280 (2004) 244 - 248] (which asserts that each max-
imal subgroup of GLn(D) is abelian) and a result in [M. Ramezan-Nassab, D.
Kiani, J. Algebra 376 (2013) 1 - 9]. In the second one we show that a maximal
subgroup of GLn(D) cannot be polycyclic-by-finite.


title: Rigidity in the Positive Mass Theorem with Charge

abstract:
  In this paper we show how a natural coupling of the Dirac equation with the
generalized Jang equation, leads to a proof of the rigidity statement in the
positive mass theorem with charge, without the maximal slicing condition,
provided a solution to the coupled system exists.


title: A Perfect Lens for Ballistic Electrons: A Kane's Model

abstract:
  The analogy between electromagnetic waves and ballistic electrons within the
Kane's model is developed and subsequently applied to a theoretical description
of a quantum version of a metamaterial planar lens. Restrictions imposed on the
perfect lens and the poor man's lens by available semiconductor band structures
are discussed. A realistic implementation is proposed for the quantum poor
man's lens, which uses specific properties of the HgTe compound. The properties
of the lens are presented on the basis of a calculated transmission of oblique
electrons through the lens structure.


title: Value Functions and Dubrovin Valuation Rings on Simple Algebras

abstract:
  In this paper we prove relationships between two generalizations of
commutative valuation theory for noncommutative central simple algebras: (1)
Dubrovin valuation rings; and (2) the value functions called gauges introduced
by Tignol and Wadsworth in [TW1] and [TW2]. We show that if v is a valuation on
a field F with associated valuation ring V and v is defectless in a central
simple F-algebra A, and C is a subring of A, then the following are equivalent:
(a) C is the gauge ring of some minimal v-gauge on A, i.e., a gauge with the
minimal number of simple components of C/J(C); (b) C is integral over V with C
= B_1 \cap ... \cap B_xi$ where each B_i is a Dubrovin valuation ring of A with
center V, and the B_i satisfy Graeter's Intersection Property. Along the way we
prove the existence of minimal gauges whenever possible and we show how gauges
on simple algebras are built from gauges on central simple algebras.


title: Correlated two-neutron emission in the decay of unbound nucleus 26O

abstract:
  The particle unbound $^{26}$O nucleus is located outside the neutron drip
line, and spontaneously decays by emitting two neutrons with a relatively long
life time due to the centrifugal barrier. We study the decay of this nucleus
with a three-body model assuming an inert $^{24}$O core and two valence
neutrons. We first point out the importance of the neutron-neutron final state
interaction in the observed decay energy spectrum. We also show that the energy
and and angular distributions for the two emitted neutrons manifest a clear
evidence for the strong neutron-neutron correlation in the three-body resonance
state. In particular, we find an enhancement of two-neutron emission in
back-to-back directions. This is interpreted as a consequence of {\it dineutron
correlation}, with which the two neutrons are spatially localized before the
emission.


title: Mathematical models for epidemic spreading on complex networks

abstract:
  We propose a model for epidemic spreading on a finite complex network with a
restriction to at most one contamination per time step. Because of a highly
discrete character of the process, the analysis cannot use the continous
approximation, widely exploited for most of the models. Using discrete approach
we investigate the epidemic threshold and the quasi-stationary distribution.
The main result is a theorem about mixing time for the process, which scales
like logarithm of the network size and which is proportional to the inverse of
the distance from the epidemic threshold. In order to present the model in the
full context, we review modern approach to epidemic spreading modeling based on
complex networks and present necessary information about random networks,
discrete-time Markov chains and their quasi-stationary distributions.


title: A note on the number of $k$-roots in $S_n$

abstract:
  The number of $k$-roots of an arbitrary permutation is expressed as an
alternating sum of $\mu$-unimodal $k$-roots of the identity permutation.


title: Flat quasi-coherent sheaves of finite cotorsion dimension

abstract:
  Let X be e quasi-compact and semi-separated scheme. If every at quasi-
coherent sheaf has finite cotorsion dimension, we prove that X is n-perfect for
some n > 0. If X is coherent and n-perfect(not necessarily of finite krull
dimension), we prove that every at quasi-coherent sheaf has finite pure
injective dimension. Also, we show that there is an equivalence K(PinfX)--->
D(FlatX) of homotopy categories, whenever K(PinfX) is the homotopy category of
pure injective at quasi-coherent sheaves and D(FlatX) is the pure derived
category of at quasi-coherent sheaves.


title: Majorana states and devices in magnetic structures

abstract:
  The pursuit for Majorana fermions is one of the top priorities in condensed
matter physics at the moment. In this work we propose a new method of
fabricating Majorana Josephson devices in systems with a weak or no spin-orbit
coupling and without external magnetic fields. Our proposal is based on curved
semiconductor wires in the proximity of superconducting elements and a small
number of nanomagnets. With this method it is possible to fabricate devices
that are not feasible by employing straight topological wire segments. The
proposed method is naturally scalable and opens up a possibility for a
systematic fabrication of arrays of Majorana states where a pair of Majorana
states is obtained from a single magnet.


title: Some special solutions to the Hyperbolic NLS equation

abstract:
  The Hyperbolic Nonlinear Schrodinger equation (HypNLS) arises as a model for
the dynamics of three-dimensional narrowband deep water gravity waves. In this
study, the Petviashvili method is exploited to numerically compute bi-periodic
time-harmonic solutions of the HypNLS equation. In physical space they
represent non-localized standing waves. Non-trivial spatial patterns are
revealed and an attempt is made to describe them using symbolic dynamics and
the language of substitutions. Finally, the dynamics of a slightly perturbed
standing wave is numerically investigated by means a highly acccurate Fourier
solver.


title: Werner-like States and Strategic Form of Quantum Games

abstract:
  We quantize prisoners dilemma, chicken game and battle of sexes to explore
the effect of quantization on their strategic form. The games start with
Werner-like state as an initial state. We show that for the measurement in
entangled basis the strategic forms of these games remain unaffected by
quantization. On the other hand when measurement is performed in product basis
then these games could not retain their strategic forms.


title: The double competition multigraph of a digraph

abstract:
  In this article, we introduce the notion of the double competition multigraph
of a digraph. We give characterizations of the double competition multigraphs
of arbitrary digraphs, loopless digraphs, reflexive digraphs, and acyclic
digraphs in terms of edge clique partitions of the multigraphs.


title: Improved Bounds on the Finite Length Scaling of Polar Codes

abstract:
  Improved bounds on the blocklength required to communicate over binary-input
channels using polar codes, below some given error probability, are derived.
For that purpose, an improved bound on the number of non-polarizing channels is
obtained. The main result is that the blocklength required to communicate
reliably scales at most as $O((I(W)-R)^{-5.77})$ where $R$ is the code rate and
$I(W)$ the symmetric capacity of the channel, $W$. The results are then
extended to polar lossy source coding at rate $R$ of a source with symmetric
distortion-rate function $D(\cdot)$. The blocklength required scales at most as
$O((D_N-D(R))^{-5.77})$ where $D_N$ is the actual distortion.


title: Faster is More Different: Mean-Field Dynamics of Innovation Diffusion

abstract:
  Based on a recent model of paradigm shifts by Bornholdt et al., we studied
mean-field opinion dynamics in an infinite population where an infinite number
of ideas compete simultaneously with their values publicly known. We found that
a highly innovative society is not characterized by heavy concentration in
highly valued ideas: Rather, ideas are more broadly distributed in a more
innovative society with faster progress, provided that the rate of adoption is
constant, which suggests a positive correlation between innovation and
technological disparity. Furthermore, the distribution is generally skewed in
such a way that the fraction of innovators is substantially smaller than has
been believed in conventional innovation-diffusion theory based on normality.
Thus, the typical adoption pattern is predicted to be asymmetric with slow
saturation in the ideal situation, which is compared with empirical data sets.


title: Residual discrete symmetry of the five-state clock model

abstract:
  It is well-known that the $q$-state clock model can exhibit a
Kosterlitz-Thouless (KT) transition if $q$ is equal to or greater than a
certain threshold, which has been believed to be five. However, recent
numerical studies indicate that helicity modulus does not vanish in the
high-temperature phase of the five-state clock model as predicted by the KT
scenario. By performing Monte Carlo calculations under the fluctuating twist
boundary condition, we show that it is because the five-state clock model does
not have the fully continuous U(1) symmetry even in the high-temperature phase
while the six-state clock model does. We suggest that the upper transition of
the five-state clock model is actually a weaker cousin of the KT transition so
that it is $q \ge 6$ that exhibits the genuine KT behavior.


title: On cohomological dimension and depth under linkage

abstract:
  Some relations between cohomological dimensions and depths of linked ideals
are investigated and discussed by various examples.


title: On Holographic Weyl Anomaly

abstract:
  We use the relation between certain diffeomorphisms in the bulk and Weyl
transformations on the boundary to build the conformal structure of the metric
in the presence of matter in the bulk. We explicitly obtain the conformal
anomaly in any spacetime dimension d in a holographic frame work in the case of
gravity coupled to the scalar fields. This way we also provide a holographic
construction of the bulk spacetime metric and of the matter fields in the bulk
of this spacetime out of sources that are related to conformal field theory
data. With the latter, we produce an asymptotic expansion of the bulk fields
and scalar fields near the boundary in terms of spacetime dimension in the
context of the AdS/CFT correspondence. We work out both the gravitational and
matter conformal anomalies of the boundary theory as a coefficient of the
infrared logarithmic divergence that appears in the on-shell action.


title:
Search for a Higgs boson decaying into a Z and a photon in pp collisions
  at sqrt(s) = 7 and 8 TeV

abstract:
  A search for a Higgs boson decaying into a Z boson and a photon is described.
The analysis is performed using proton-proton collision datasets recorded by
the CMS detector at the LHC. Events were collected at center-of-mass energies
of 7 TeV and 8 TeV, corresponding to integrated luminosities of 5.0 and 19.6
inverse femtobarns, respectively. The selected events are required to have
opposite-sign electron or muon pairs. No excess above standard model
predictions has been found in the 120-160 GeV mass range and the first limits
on the Higgs boson production cross section times the H to Z gamma branching
fraction at the LHC have been derived. The observed at 95% confidence level
limits are between about 4 and 25 times the standard model cross section times
the branching fraction. For a standard model Higgs boson mass of 125 GeV the
expected limit at the 95% confidence level is 10 and the observed limit is 9.5.
Models predicting the Higgs boson production cross section times the Higgs to Z
gamma branching fraction to be larger than one order of magnitude of the
standard model prediction are excluded for most of the 125-157 GeV mass range.


title: Investigating isomorphs with the topological cluster classification

abstract:
  Isomorphs are lines in the density-temperature plane of certain
"strongly-correlating" or "Roskilde simple" liquids where two-point structure
and dynamics have been shown to be close to identical up to a scale
transformation. Here we consider such a liquid, a Lennard-Jones glassformer,
and investigate the behavior along isomorphs of higher-order structural and
dynamical correlations. We then consider an inverse power law reference system
mapped to the Lennard-Jones system [Pedersen et al., Phys. Rev. Lett. 105,
157801 (2010)]. Using the topological cluster classification to identify
higher-order structures, in both systems we find bicapped square anti-prisms,
which are known to be a locally favored structure in the Lennard-Jones
glassformer. The population of these locally favored structures is up to 80%
higher in the Lennard-Jones system than the equivalent inverse power law
system. The structural relaxation time of the two systems, on the other hand,
is almost identical, and the four-point dynamical susceptibility is marginally
higher in the inverse power law system. Upon cooling the lifetime of the
locally favored structures in the Lennard-Jones system are up to 40% higher
relative to the reference system.


title:
Identification of structure in condensed matter with the topological
  cluster classification

abstract:
  We describe the topological cluster classification (TCC) algorithm. The TCC
detects local structures with bond topologies similar to isolated clusters
which minimise the potential energy for a number of monatomic and binary simple
liquids with $m\leq13$ particles. We detail a modified Voronoi bond detection
method that optimizes the cluster detection. The method to identify each
cluster is outlined, and a test example of Lennard-Jones liquid and crystal
phases is considered and critically examined.


title: On a Wilson lines approach to the study of jet quenching

abstract:
  We address the geometrical structure of the "skewed" correlator of two
space-like separated (almost) oppositely directed Wilson lines. Similar objects
occur in the analysis of the transverse-momentum broadening probability
function, the first moment of which is associated with the jet quenching
parameter. We start from the Euclidean space formulation and then transform the
result to the Minkowski light-cone geometry, arguing that this procedure is
consistent in the leading order of the perturbative expansion. We discuss as
well the issues of the UV, rapidity and IR singularities, and possible use of
the proposed approach in lattice simulations.


title: Optimal Recombination in Genetic Algorithms

abstract:
  This paper surveys results on complexity of the optimal recombination problem
(ORP), which consists in finding the best possible offspring as a result of a
recombination operator in a genetic algorithm, given two parent solutions. We
consider efficient reductions of the ORPs, allowing to establish polynomial
solvability or NP-hardness of the ORPs, as well as direct proofs of hardness
results.


title:
From Lie Algebras to Lie Groups within Synthetic Differential
  Geometry:Weil Sprouts of Lie's Third Fundamental Theorem

abstract:
  Weil prolongations of a Lie group are naturally Lie groups. It is not known
in the theory of infinite-dimensional Lie groups how to construct a Lie group
with a given Lie algebra as its Lie algebra or whether there exists such a Lie
group at all. We will show in this paper how to construct some Weil
prolongations of this mythical Lie group from a given Lie algebra. We will do
so within our favorite framework of synthetic differential geometry.


title: Realizability Interpretation of PA by Iterated Limiting PCA

abstract:
  For any partial combinatory algebra (PCA for short) A, the class of
A-representable partial functions from N to A quotiented by the filter of
cofinite sets of N, is a PCA such that the representable partial functions are
exactly the limiting partial functions of A-representable partial
functions(Akama, "Limiting partial combinatory algebras" Theoret. Comput. Sci.
Vol.311 2004). The n-times iteration of this construction results in a PCA that
represents any n-iterated limiting partial recursive functions, and the
inductive limit of the PCAs over all n is a PCA that represents any
arithmetical, partial function. Kleene's realizability interpretation over the
former PCA interprets the logical principles of double negation elimination for
\Sigma^0_n-formulas, and that over the latter PCA interprets Peano's arithmetic
(PA for short). A hierarchy of logical systems between Heyting's arithmetic and
PA is used to discuss the prenex normal form theorem, the relativized
independence-of-premise schemes, and "PA is an unbounded extension of HA."