title:
On the Spin Bias of Satellite Galaxies in the Local Group-like
  Environment

abstract:
  We utilize the Millennium-II simulation databases to study the spin bias of
dark subhalos in the Local Group-like systems which have two prominent
satellites with comparable masses. Selecting the group-size halos with total
mass similar to that of the Local Group (LG) from the friends-of-friends halo
catalog and locating their subhalos from the substructure catalog, we determine
the most massive (main) and second to the most massive (submain) ones among the
subhalos hosted by each selected halo. When the dimensionless spin parameter
(lambda) of each subhalo is derived from its specific angular momentum and
circular velocity at virial radius, a signal of correlation is detected between
the spin parameters of the subhalos and the main-to-submain mass ratios of
their host halos at z=0: The higher main-to-submain mass ratio a host halo has,
the higher mean spin parameter its subhalos have. It is also found that the
correlations exist even for the subhalo progenitors at z=0.5 and z=1. Our
interpretation of this result is that the subhalo spin bias is not a transient
effect but an intrinsic property of a LG-like system with higher main-to-
submain mass ratio, caused by stronger anisotropic stress in the region. A
cosmological implication of our result is also discussed.


title: Characterizing quark gluon plasma by thermal photons and lepton pairs

abstract:
  The photon spectra measured by the ALICE collaboration in Pb+Pb collisions at
Large Hadron Collider (LHC) energies has been analyzed with a view of
extracting the properties of thermal system formed in these collisions. The
results of the analysis are compared with the previously studied spectra
measured at Super Proton Synchrotron (SPS) and Relativistic Heavy Ion Collider
(RHIC) energies. The thermal dilepton spectra from the Pb+Pb collision at LHC
energy has been predicted for the initial conditions constrained by the thermal
photon spectra at the same collision conditions. The slope of the photon has
been used to estimate the rise in the effective degeneracy with the charged
particle multiplicity of the system. The slopes of the lepton pair spectra for
different invariant mass windows have been used to conjecture the average
radial flow velocity of the high temperature phase.


title: An extension of one direction in Marty's normality criterion

abstract:
  We prove an extension of one direction in Marty's theorem where the spherical
derivative is replaced by a more general quantity involving higher derivatives.


title: Potts Models with (17) Invisible States on Thin Graphs

abstract:
  The order of a phase transition is usually determined by the nature of the
symmetry breaking at the phase transition point and the dimension of the model
under consideration. For instance, q-state Potts models in two dimensions
display a second order, continuous transition for q = 2,3,4 and first order for
higher q.
  Tamura et al recently introduced Potts models with "invisible" states which
contribute to the entropy but not the internal energy and noted that adding
such invisible states could transmute continuous transitions into first order
transitions. This was observed both in a Bragg-Williams type mean-field
calculation and 2D Monte-Carlo simulations. It was suggested that the invisible
state mechanism for transmuting the order of a transition might play a role
where transition orders inconsistent with the usual scheme had been observed.
  In this paper we note that an alternative mean-field approach employing
3-regular random ("thin") graphs also displays this change in the order of the
transition as the number of invisible states is varied, although the number of
states required to effect the transmutation, 17 invisible states when there are
2 visible states, is much higher than in the Bragg-Williams case. The
calculation proceeds by using the equivalence of the Potts model with 2 visible
and r invisible states to the Blume-Emery-Griffiths (BEG) model, so a
by-product is the solution of the BEG model on thin random graphs.


title: The Fourier dimension of Brownian limsup fractals

abstract:
  Robert Kaufman's proof that the set of rapid points of Brownian motion has a
Fourier dimension equal to its Hausdorff dimension was first published in 1974.
A study of the proof of the original paper revealed several gaps in the
arguments and a slight inaccuracy in the main theorem. This paper presents a
new version of the construction and incorporates some recent results in order
to establish a corrected version of Kaufman's theorem. The method of proof can
then be extended to show that functionally determined rapid points of Brownian
motion also form Salem sets for absolutely continuous functions of finite
energy.


title:
Low-threshold whispering-gallery-mode microlasers fabricated in a Nd:
  glass substrate by three-dimensional femtosecond laser micromachining

abstract:
  We report on fabrication of whispering-gallery-mode microlasers in a Nd:glass
chip by femtosecond laser three-dimensional (3D) micromachining. Main
fabrication procedures include the fabrication of freestanding microdisks
supported by thin pillars by femtosecond laser ablation of the glass substrate
immersed in water, followed by CO2 laser annealing for surface smoothing.
Lasing is observed at a pump threshold as low as ~69 {\mu}W at room temperature
with a continuous-wave laser diode operating at 780nm. This technique allows
for fabrication of microcavities of high quality factors in various dielectric
materials such as glasses and crystals.


title: On the number of nonequivalent propelinear extended perfect codes

abstract:
  The paper proves that there exist an exponential number of nonequivalent
propelinear extended perfect binary codes of length growing to infinity.
Specifically, it is proved that all transitive extended perfect binary codes
found by Potapov are propelinear. All such codes have small rank, which is one
more than the rank of the extended Hamming code of the same length. We
investigate the properties of these codes and show that any of them has a
normalized propelinear representation.


title: On the minimum mass ratio of W UMa binaries

abstract:
  Using Eggleton's stellar evolution code, we study the minimum mass ratio
($q_{\rm min}$) of W Ursae Majoris (W UMa) binaries that have different primary
masses. It is found that the minimum mass ratio of W UMa binaries decreases
with increasing mass of the primary if the primary's mass is less than about
1.3$M_{\rm \odot}$, and above this mass the ratio is roughly constant. By
comparing the theoretical minimum mass ratio with the observational data, it is
found that the existence of low-$q$ systems can be explained by the different
structure of the primaries with different masses. This suggests that the
dimensionless gyration radius ($k_1^2$) and thus the structure of the primary
is very important in determining the minimum mass ratio. In addition, we
investigate the mass loss during the merging process of W UMa systems and
calculate the rotation velocities of the single stars formed by the merger of W
UMa binaries due to tidal instability. It is found that in the case of the
conservation of mass and angular momentum, the merged single stars rotate with
a equatorial velocity of about $588\sim819$ km s$^{-1}$, which is much larger
than their break-up velocities ($v_{\rm b}$). This suggests that the merged
stars should extend to a very large radius (3.7$\sim$5.3 times the radii of the
primaries) or W UMa systems would lose a large amount of mass (21$\sim$33 per
cent of the total mass) during the merging process. If the effect of magnetic
braking is considered, the mass loss decreases to be 12$\sim$18 per cent of
their total masses. This implies that the significant angular momentum and mass
might be lost from W UMa systems in the course of the merging process, and this
kind of mass and angular momentum loss might be driven by the release of
orbital energy of the secondaries, which is similar to common-envelope
evolution.


title:
Orbital selective correlations between nesting/scattering/Lifshitz
  transition and the superconductivity in AFe1-xCoxAs (A=Li, Na)

abstract:
  The correlations between the superconductivity in iron pnictides and their
electronic structures are elusive and controversial so far. Here through
angle-resolved photoemission spectroscopy measurements, we show that such
correlations are rather distinct in AFe$_{1-x}$Co$_x$As (A=Li, Na), but only
after one realizes that they are orbital selective. We found that the
superconductivity is enhanced by the Fermi surface nesting, but only when it is
between $d_{xz}/d_{yz}$ Fermi surfaces, while for the $d_{xy}$ orbital, even
nearly perfect Fermi surface nesting could not induce superconductivity.
Moreover, the superconductivity is completely suppressed just when the
$d_{xz}/d_{yz}$ hole pockets sink below Fermi energy and evolve into an
electron pocket. Our results thus establish the orbital selective relation
between the Fermiology and the superconductivity in iron-based superconductors,
and substantiate the critical role of the $d_{xz}/d_{yz}$ orbitals.
Furthermore, around the zone center, we found that the $d_{xz}/d_{yz}$-based
bands are much less sensitive to impurity scattering than the $d_{xy}$-based
band, which explains the robust superconductivity against heavy doping in
iron-based superconductors.


title: Relations between minimal usco and cusco maps

abstract: We study relations between minimal usco and cusco maps.


title: Stable Large-Scale Perturbations in Interacting Dark-Energy Model

abstract:
  It is found that the evolutions of density perturbations on the super-Hubble
scales are unstable in the model with dark-sector interaction $Q$ proportional
to the energy density of cold dark matter (CDM) $\rho_m$ and constant equation
of state parameter of dark energy $w_d$. In this paper, to avoid the
instabilities, we suggest a new covariant model for the energy-momentum
transfer between DE and CDM. Then we show that the the large-scale
instabilities of curvature perturbations can be avoided in our model in the
universe filled only by DE and CDM. Furthermore, by including the additional
components of radiation and baryons, we calculate the dominant non-adiabatic
modes in the radiation era and find that the modes grow in the power law with
exponent at the order of unit.


title:
Probing phase-space noncommutativity through quantum beating, missing
  information and the thermodynamic limit

abstract:
  In this work we examine the effect of phase-space noncommutativity on some
typically quantum properties such as quantum beating, quantum information, and
decoherence. To exemplify these issues we consider the two-dimensional
noncommutative quantum harmonic oscillator whose components behavior we monitor
in time. This procedure allows us to determine how the noncommutative
parameters are related to the missing information quantified by the linear
quantum entropy and by the mutual information between the relevant Hilbert
space coordinates. Particular questions concerning the thermodynamic limit of
some relevant properties are also discussed in order to evidence the effects of
noncommutativity. Finally, through an analogy with the Zeeman effect, we
identify how some aspects of the axial symmetry of the problem suggest the
possibility of decoupling the noncommutative quantum perturbations from
unperturbed commutative well-known solutions.


title: Growth Patterns of US Children from 1963 to 2012

abstract:
  Anthropometric measurements such as weight, stature (height), and body mass
index (BMI) provide reliable indicators of children's growth. The 2000 CDC
growth charts are the national standards in the United States for these
important measures. But these growth charts were generated using data from
1963-1994. To understand the growth patterns of US children since 1994, we
generate weight-for-age, stature-for-age and BMI-for-age percentile curves for
both boys and girls aged 2-20 through the methods used to generate the 2000 CDC
growth charts. Our datasets are from the National Health and Nutrition
Examination Survey (NHANES) for years 1999-2010 and and from NorthShore
University HealthSystem's Enterprise Data Warehouse (NS-EDW) for years
2006-2012. The weight and BMI percentile curves generated from NS-EDW and
NHANES data differ substantially from the CDC percentile curves, while those
for stature do not differ substantially. We conclude that the population weight
and BMI values of US children in recent years have increased significantly
since 2000 and the 2000 CDC growth charts may no longer be applicable to the
current population of US children. Our charts poignantly reveals the increasing
obesity of American children.


title:
Lipkin's conservation law, Noether's theorem, and the relation to
  optical helicity

abstract:
  A simple conserved quantity for electromagnetic fields in vacuum was
discovered by Lipkin in 1964. In recent years this "zilch" has been used as a
measure of the chirality of light. The conservation of optical zilch is here
derived from a simple symmetry of the standard electromagnetic action. The
symmetry transformation allows the identification of circularly polarized plane
waves as zilch eigenstates. The same symmetry is present for electromagnetism
in a homogeneous, dispersive medium, allowing the derivation of the zilch
density and flux in such a medium. Optical helicity density and flux are also
derived for a homogeneous, dispersive medium. For monochromatic beams in
vacuum, optical zilch is proportional to optical helicity. This monochromatic
zilch-helicity relation acquires a factor of the square of the phase index in a
dispersive medium.


title: Entanglement and Particle Identity: A Unifying Approach

abstract:
  It has been known for some years that entanglement entropy obtained from
partial trace does not provide the correct entanglement measure when applied to
systems of identical particles. Several criteria have been proposed that have
the drawback of being different according to whether one is dealing with
fermions, bosons or distinguishable particles. In this Letter, we give a
precise and mathematically natural answer to this problem. Our approach is
based on the use of the more general idea of restriction of states to
subalgebras. It leads to a novel approach to entanglement, suitable to be used
in general quantum systems and specially in systems of identical particles.
This settles some recent controversy regarding entanglement for identical
particles. The prospects for applications of our criteria are wide-ranging,
from spin chains in condensed matter to entropy of black holes.


title:
Electromagnetic energy within single-resonance chiral metamaterial
  spheres

abstract:
  We derive an exact expression for the time-averaged electromagnetic energy
inside a chiral dispersive sphere irradiated by a plane wave. The dispersion
relations correspond to a chiral metamaterial consisting of uncoupled
single-resonance helical resonators. Using a field decomposition scheme and a
general expression for the electromagnetic energy density in bi-anisotropic
media, we calculate the Lorenz-Mie solution for the internal fields in a medium
that is simultaneously magnetic and chiral. We also obtain an explicit
analytical relation between the internal electromagnetic field and the
absorption cross-section. This result is applied to demonstrate that strong
chirality leads to an off-resonance field enhancement within weakly absorb.ing
spheres.


title:
On the effects of Bohm's potential on a macroscopic system of
  self-interacting particles

abstract:
  We consider an instationary macroscopic system of self-interacting particles
with an additional potential, the so called Bohm's potential. We study the
existence of non-negative global solutions to the (4-th order) system of
equations and allude the differences to results obtained for classical models.
The problem is considered on a bounded domain up to three space dimension,
subject to initial and Neumann boundary condition for the particle density, and
Dirichlet boundary condition for the self-interacting potential. Moreover, the
initial datum is only assumed to be non-negative and to satisfy a weak
integrability condition.


title:
Learning AMP Chain Graphs and some Marginal Models Thereof under
  Faithfulness: Extended Version

abstract:
  This paper deals with chain graphs under the Andersson-Madigan-Perlman (AMP)
interpretation. In particular, we present a constraint based algorithm for
learning an AMP chain graph a given probability distribution is faithful to.
Moreover, we show that the extension of Meek's conjecture to AMP chain graphs
does not hold, which compromises the development of efficient and correct
score+search learning algorithms under assumptions weaker than faithfulness.
  We also introduce a new family of graphical models that consists of
undirected and bidirected edges. We name this new family maximal
covariance-concentration graphs (MCCGs) because it includes both covariance and
concentration graphs as subfamilies. However, every MCCG can be seen as the
result of marginalizing out some nodes in an AMP CG. We describe global, local
and pairwise Markov properties for MCCGs and prove their equivalence. We
characterize when two MCCGs are Markov equivalent, and show that every Markov
equivalence class of MCCGs has a distinguished member. We present a constraint
based algorithm for learning a MCCG a given probability distribution is
faithful to.
  Finally, we present a graphical criterion for reading dependencies from a
MCCG of a probability distribution that satisfies the graphoid properties, weak
transitivity and composition. We prove that the criterion is sound and complete
in certain sense.


title: Simple surface singularities

abstract:
  By the famous ADE classification rational double points are simple. Rational
triple points are also simple. We conjecture that the simple normal surface
singularities are exactly those rational singularities, whose resolution graph
can be obtained from the graph of a rational double point or rational triple
point by making (some) vertex weights more negative. For rational singularities
we show one direction in general, and the other direction (simpleness) within
the special classes of rational quadruple points and of sandwiched
singularities.


title: Precision top pair production at hadron colliders

abstract:
  We demonstrate the impact of recent NNLO calculations on precision top quark
phenomenology.


title:
The Relevance of the Preparation Concept in the Interpretation of
  Quantum Formalism

abstract:
  The preparation procedure, an undefined notion in quantum theory, has not had
the relevance that it deserves in the interpretation of quantum mechanical
formalism. Here we utilize the concepts of identical and similar preparation
procedures to show the conceptual differences and mutual interconnections
between the statistical and the conventional interpretation of quantum
formalism. Although the statistical understanding, and its final logical
consequence, hidden variables theories (this connexion being explained in the
text), have a great intuitive appeal due to its fewer ontological difficulties,
both recent experimental results and some theoretical developments seem to
support an epistemic alternative closer to the conventional one. Nevertheless,
we must not rule out the possibility that new theorems or new explanatory
principles may modify the reigning supremacy of this interpretation.


title: Non-Asymptotic Output Statistics of Random Binning and Its Applications

abstract:
  In this paper we develop a finite blocklength version of the Output
Statistics of Random Binning (OSRB) framework. The framework is shown to be
optimal in the point-to-point case. New second order regions for broadcast
channel and wiretap channel with strong secrecy criterion are derived.


title:
A Technique for Deriving One-Shot Achievability Results in Network
  Information Theory

abstract:
  This paper proposes a novel technique to prove a one-shot version of
achievability results in network information theory. The technique is not based
on covering and packing lemmas. In this technique, we use an stochastic encoder
and decoder with a particular structure for coding that resembles both the ML
and the joint-typicality coders. Although stochastic encoders and decoders do
not usually enhance the capacity region, their use simplifies the analysis. The
Jensen inequality lies at the heart of error analysis, which enables us to deal
with the expectation of many terms coming from stochastic encoders and decoders
at once. The technique is illustrated via several examples: point-to-point
channel coding, Gelfand-Pinsker, Broadcast channel (Marton), Berger-Tung,
Heegard-Berger/Kaspi, Multiple description coding and Joint source-channel
coding over a MAC. Most of our one-shot results are new. The asymptotic forms
of these expressions is the same as that of classical results. Our one-shot
bounds in conjunction with multi-dimensional Berry-Essen CLT imply new results
in the finite blocklength regime. In particular applying the one-shot result
for the memoryless broadcast channel in the asymptotic case, we get the entire
region of Marton's inner bound without any need for time-sharing.


title: General Bilinear Forms

abstract:
  We introduce the new notion of general bilinear forms (generalizing
sesquilinear forms) and prove that for every ring $R$ (not necessarily
commutative, possibly without involution) and every right $R$-module $M$ which
is a generator (i.e. $R_R$ is a summand of $M^n$ for some $n\in\N$), there is a
one-to-one correspondence between the anti-automorphisms of $\End(M)$ and the
general regular bilinear forms on $M$, considered up to similarity. This
generalizes a well-known similar correspondence in the case $R$ is a field. We
also demonstrate that there is no such correspondence for arbitrary
$R$-modules.
  We use the generalized correspondence to show that there is a canonical set
isomorphism between the orbits of the left action of $\Inn(R)$ on the
anti-automorphisms of $R$ and the orbits of the left action of $\Inn(M_n(R))$
on the anti-automorphisms of $M_n(R)$, provided $R_R$ is the only right
$R$-module $N$ satisfying $N^n\cong R^n$. We also prove a variant of a theorem
of Osborn. Namely, we classify all semisimple rings with involution admitting
no non-trivial idempotents that are invariant under the involution.


title:
Orbital-Selective Spin Texture and its Manipulation in a Topological
  Insulator

abstract:
  Topological insulators represent a new quantum state of matter that are
insulating in the bulk but metallic on the edge or surface. In the Dirac
surface state, it is well-established that the electron spin is locked with the
crystal momentum. Here we report a new phenomenon of the spin texture locking
with the orbital texture in a topological insulator Bi2Se3. We observe
light-polarization-dependent spin texture of both the upper and lower Dirac
cones that constitutes strong evidence of the orbital-dependent spin texture in
Bi2Se3. The different spin texture detected in variable polarization geometry
is the manifestation of the spin-orbital texture in the initial state combined
with the photoemission matrix element effects. Our observations provide a new
orbital degree of freedom and a new way of light manipulation in controlling
the spin structure of the topological insulators that are important for their
future applications in spin-related technologies.


title: Low-complexity dominance-based Sphere Decoder for MIMO Systems

abstract:
  The sphere decoder (SD) is an attractive low-complexity alternative to
maximum likelihood (ML) detection in a variety of communication systems. It is
also employed in multiple-input multiple-output (MIMO) systems where the
computational complexity of the optimum detector grows exponentially with the
number of transmit antennas. We propose an enhanced version of the SD based on
an additional cost function derived from conditions on worst case interference,
that we call dominance conditions. The proposed detector, the king sphere
decoder (KSD), has a computational complexity that results to be not larger
than the complexity of the sphere decoder and numerical simulations show that
the complexity reduction is usually quite significant.


title:
Ratchet effect driven by Coulomb friction: the asymmetric Rayleigh
  piston

abstract:
  The effect of Coulomb friction is studied in the framework of collisional
ratchets. It turns out that the average drift of these devices can be expressed
as the combination of a term related to the lack of equipartition between the
probe and the surrounding bath, and a term featuring the average frictional
force. We illustrate this general result in the asymmetric Rayleigh piston,
showing how Coulomb friction can induce a ratchet effect in a Brownian particle
in contact with an equilibrium bath. An explicit analytical expression for the
average velocity of the piston is obtained in the rare collision limit.
Numerical simulations support the analytical findings.


title: The Baum-Connes conjecture, Swan group actions and controlled topology

abstract:
  We give a new proof of some cases of the Baum-Connes conjecture along the
lines of a proof of the Farrell-Jones conjecture.


title: A family of simple weight modules over the Virasoro algebra

abstract:
  Using simple modules over the derivation Lie algebra $C[t]\frac{d}{d t}$ of
the associative polynomial algebra $C[t]$, we construct new weight Virasoro
modules with all weight spaces infinite dimensional. We determine necessary and
sufficient conditions for these new weight Virasoro modules to be simple, and
determine necessary and sufficient conditions for two such weight Virasoro
modules to be isomorphic. If such a weight Virasoro module is not simple, we
obtain all its submodules. In particular, we completely determine the
simplicity and the isomorphism classes of the weight modules defined in [C.
Conley, C. Martin; A family of irreducible representations of the Witt Lie
algebra with infinite-dimensional weight spaces. Compos. Math., 128(2),
153-175(2001)] which are a small portion of the modules constructed in this
paper.


title: Thermal valence-bond-solid transition of quantum spins in two dimensions

abstract:
  We study the S=1/2 Heisenberg (J) model on the two-dimensional square lattice
in the presence of additional higher-order spin interactions (Q) which lead to
a valence-bond-solid (VBS) ground state. Using quantum Monte Carlo simulations,
we analyze the thermal VBS transition. We find continuously varying exponents,
with the correlation-length exponent "nu" close to the Ising value for large
Q/J and diverging when Q/J approaches the quantum-critical point (the critical
temperature Tc -> 0). This is in accord with the theory of deconfined
quantum-critical points, which predicts that the transition should approach a
Kosterlitz-Thouless (KT) fixed point when Tc -> 0+ (while the transition versus
Q/J for T=0 is in a different class). We find explicit evidence for KT physics
by studying the emergence of U(1) symmetry of the order parameter at T=T_c when
Tc -> 0.


title: Distributed allocation of mobile sensing swarms in gyre flows

abstract:
  We address the synthesis of distributed control policies to enable a swarm of
homogeneous mobile sensors to maintain a desired spatial distribution in a
geophysical flow environment, or workspace. In this article, we assume the
mobile sensors (or robots) have a "map" of the environment denoting the
locations of the Lagrangian coherent structures or LCS boundaries. Based on
this information, we design agent-level hybrid control policies that leverage
the surrounding fluid dynamics and inherent environmental noise to enable the
team to maintain a desired distribution in the workspace. We establish the
stability properties of the ensemble dynamics of the distributed control
policies. Since realistic quasi-geostrophic ocean models predict double-gyre
flow solutions, we use a wind-driven multi-gyre flow model to verify the
feasibility of the proposed distributed control strategy and compare the
proposed control strategy with a baseline deterministic allocation strategy.
Lastly, we validate the control strategy using actual flow data obtained by our
coherent structure experimental testbed.


title: A scaling law beyond Zipf's law and its relation to Heaps' law

abstract:
  The dependence with text length of the statistical properties of word
occurrences has long been considered a severe limitation quantitative
linguistics. We propose a simple scaling form for the distribution of absolute
word frequencies which uncovers the robustness of this distribution as text
grows. In this way, the shape of the distribution is always the same and it is
only a scale parameter which increases linearly with text length. By analyzing
very long novels we show that this behavior holds both for raw, unlemmatized
texts and for lemmatized texts. For the latter case, the word-frequency
distribution is well fit by a double power law, maintaining the Zipf's exponent
value $\gamma\simeq 2$ for large frequencies but yielding a smaller exponent in
the low frequency regime. The growth of the distribution with text length
allows us to estimate the size of the vocabulary at each step and to propose an
alternative to Heaps' law, which turns out to be intimately connected to Zipf's
law, thanks to the scaling behavior.


title: Limit on Time-Energy Uncertainty with Multipartite Entanglement

abstract:
  We establish a relation between the geometric time-energy uncertainty and
multipartite entanglement. In particular, we show that the time-energy
uncertainty relation is bounded below by the geometric measure of multipartite
entanglement for an arbitrary quantum evolution of any multipartite system. The
product of the time-averaged speed of the quantum evolution and the time
interval of the evolution is bounded below by the multipartite entanglement of
the target state. This relation holds for pure as well as for mixed states. We
provide examples of physical systems for which the bound reaches close to
saturation.


title:
On the Achievable Error Region of Physical Layer Authentication
  Techniques over Rayleigh Fading Channels

abstract:
  For a physical layer message authentication procedure based on the comparison
of channel estimates obtained from the received messages, we focus on an outer
bound on the type I/II error probability region. Channel estimates are modelled
as multivariate Gaussian vectors, and we assume that the attacker has only some
side information on the channel estimate, which he does not know directly. We
derive the attacking strategy that provides the tightest bound on the error
region, given the statistics of the side information. This turns out to be a
zero mean, circularly symmetric Gaussian density whose correlation matrices may
be obtained by solving a constrained optimization problem. We propose an
iterative algorithm for its solution: Starting from the closed form solution of
a relaxed problem, we obtain, by projection, an initial feasible solution;
then, by an iterative procedure, we look for the fixed point solution of the
problem. Numerical results show that for cases of interest the iterative
approach converges, and perturbation analysis shows that the found solution is
a local minimum.


title: Tunneling in cosine potential with periodic boundary conditions

abstract:
  In this paper we discuss three methods to calculate energy splitting in
cosine potential on a circle, Bloch waves, semi--classical approximation and
restricted basis approach. While the Bloch wave method gives only a qualitative
result, with the WKB method we are able to determine its unknown coefficients.
The numerical approach is most exact and enables us to extract further
corrections to previous results.


title: Temperature-dependent optical conductivity of layered LaSrFeO_4

abstract:
  Compounds with intermediate-size transition metals such as Fe or Mn are close
to the transition between charge-transfer systems and Mott-Hubbard systems. We
study the optical conductivity \sigma(\omega) of insulating layered LaSrFeO_4
in the energy range 0.5 - 5.5 eV from 15 K to 250 K by the use of spectroscopic
ellipsometry in combination with transmittance measurements. A multipeak
structure is observed in both \sigma^a(\omega) and \sigma^c(\omega). The
layered structure gives rise to a pronounced anisotropy, thereby offering a
means to disentangle Mott-Hubbard and charge-transfer absorption bands. We find
strong evidence that the lowest dipole-allowed excitation in LaSrFeO_4 is of
Mott-Hubbard type. This rather unexpected result can be attributed to Fe 3d - O
2p hybridization and in particular to the layered structure with the associated
splitting of the e_g level. In general, Mott-Hubbard absorption bands may show
a strong dependence on temperature. This is not the case in LaSrFeO_4, in
agreement with the fact that spin-spin and orbital-orbital correlations between
nearest neighbors do not vary strongly below room temperature in this compound
with a high-spin 3d^5 configuration and a Neel temperature of T_N = 366 K.


title: Ranks of GL2 Iwasawa modules of elliptic curves

abstract:
  Let $p >= 5$ be a prime and $E$ an elliptic curve without complex
multiplication and let $K_\infty=Q(E[p^\infty])$ be a pro-$p$ Galois extension
over a number field $K$. We consider $X(E/K_\infty)$, the Pontryagin dual of
the $p$-Selmer group $\Sel_{p^\infty}(E/K_\infty)$. The size of this module is
roughly measured by its rank $\tau$ over a $p$-adic Galois group algebra
$\Lambda(H)$, which has been studied in the past decade. We prove $\tau >= 2$
for almost every elliptic curve under standard assumptions. Following from a
result of Coates et al, $\tau$ is odd if and only if $[Q(E[p]) \colon Q]/2$ is
odd; we give an alternative proof. We show that this is equivalent to $p=7$,
$E$ having a 7-isogeny and an easily verifiable condition on the discriminant.
Up to isogeny, these curves are parametrised by two rational variables using
recent work of Greenberg, Rubin, Silverberg and Stoll. We find that $\tau = 1$
and $j \notin Z$ is impossible, while $\tau = 1$ and $j \in Z$ can occur in at
most 8 explicitly known elliptic curves. The rarity of $\tau=1$ was expected
from Iwasawa theory, but the proof is essentially elementary.


title: Sequential ends of metric spaces

abstract:
  We develop an analog to the ends of a metric space for the category of coarse
metric spaces and show that it is equivalent to a previously defined coarse
invariant.


title: Stochastic acceleration in accreting black holes

abstract:
  We present an extension of the BELM code (Belmont et al 2008) to investigate
the microphysics of particle acceleration in black holes accretion disc corona.
The updated version of the code accounts for the dynamics of resonant slab
waves as well as their interaction with both leptons or protons. It is found
that the proton temperature is an important regulating effect of the stochastic
particle acceleration process in accretion disk corona. We present a
preliminary fit of the high soft spectral state of Cygnus X-1.


title: On the Energy-Momentum Flux in G\"{o}del-type Models

abstract:
  In this paper we work in the context of Teleparallelism Equivalent to General
Relativity (TEGR) in order to construct the energy-momentum flux for
G\"odel-type solutions of Einstein's equations. We use an stationary observer,
which is settled by the tetrad choice, to obtain the gravitational pressure for
each direction of space in cartesian coordinates. Then we write down the total
pressure for each direction in terms of the pressure of the fluid, thus we are
able to identify role of the gravitational pressure.


title: Simplification Methods for Sum-of-Squares Programs

abstract:
  A sum-of-squares is a polynomial that can be expressed as a sum of squares of
other polynomials. Determining if a sum-of-squares decomposition exists for a
given polynomial is equivalent to a linear matrix inequality feasibility
problem. The computation required to solve the feasibility problem depends on
the number of monomials used in the decomposition. The Newton polytope is a
method to prune unnecessary monomials from the decomposition. This method
requires the construction of a convex hull and this can be time consuming for
polynomials with many terms. This paper presents a new algorithm for removing
monomials based on a simple property of positive semidefinite matrices. It
returns a set of monomials that is never larger than the set returned by the
Newton polytope method and, for some polynomials, is a strictly smaller set.
Moreover, the algorithm takes significantly less computation than the convex
hull construction. This algorithm is then extended to a more general
simplification method for sum-of-squares programming.


title: A J-band detection of the sub-stellar mass donor in SDSS J1433+1011

abstract:
  We present time-resolved J-band spectroscopy of the short period cataclysmic
variable SDSS J143317.78+101123.3. We detect absorption lines from the
sub-stellar donor star in this system, which contributes 38 +/- 5% to the
J-band light. From the relative strengths of the absorption lines in the
J-band, we estimate the spectral type of the donor star to be L2 +/- 1. These
data are the first spectroscopic detection of a confirmed sub-stellar donor in
a cataclysmic variable, and the spectral type is consistent with that expected
from semi-empirical evolutionary models.
  Using skew mapping, we have been able to derive an estimate for the radial
velocity of the donor of Kd = 520 +/- 60 km/s. This value is consistent with,
though much less precise than, predictions from mass determinations found via
photometric fitting of the eclipse light curves.


title: On Inversion in Z_{2^n-1}

abstract:
  In this paper we determined explicitly the multiplicative inverses of the
Dobbertin and Welch APN exponents in Z_{2^n-1}, and we described the binary
weights of the inverses of the Gold and Kasami exponents. We studied the
function \de(n), which for a fixed positive integer d maps integers n\geq 1 to
the least positive residue of the inverse of d modulo 2^n-1, if it exists. In
particular, we showed that the function \de is completely determined by its
values for 1 \leq n \leq \ordb, where \ordb is the order of 2 modulo the
largest odd divisor of d.


title: The two-component Camassa-Holm system in weighted $L_p$ spaces

abstract:
  We present some new persistence results for the non-periodic two-component
Camassa-Holm (2CH) system in weighted $L_p$ spaces. Working with moderate
weight functions that are commonly used in time-frequency analysis, the paper
generalizes some recent persistence results for the Camassa-Holm equation [L.
Brandolese, Int. Math. Res. Notices 22 (2012) 5161-81] to its supersymmetric
extension. As an application we discuss the spatial asymptotic profile of
solutions to 2CH.


title: Spectral Theory for Networks with Attractive and Repulsive Interactions

abstract:
  There is a wealth of applied problems that can be posed as a dynamical system
defined on a network with both attractive and repulsive interactions. Some
examples include: understanding synchronization properties of nonlinear
oscillator;, the behavior of groups, or cliques, in social networks; the study
of optimal convergence for consensus algorithm; and many other examples.
Frequently the problems involve computing the index of a matrix, i.e. the
number of positive and negative eigenvalues, and the dimension of the kernel.
In this paper we consider one of the most common examples, where the matrix
takes the form of a signed graph Laplacian. We show that the there are
topological constraints on the index of the Laplacian matrix related to the
dimension of a certain homology group. In certain situations, when the homology
group is trivial, the index of the operator is rigid and is determined only by
the topology of the network and is independent of the strengths of the
interactions. In general these constraints give upper and lower bounds on the
number of positive and negative eigenvalues, with the dimension of the homology
group counting the number of eigenvalue crossings. The homology group also
gives a natural decomposition of the dynamics into "fixed" degrees of freedom,
whose index does not depend on the edge-weights, and an orthogonal set of
"free" degrees of freedom, whose index changes as the edge weights change. We
also present some numerical studies of this problem for large random matrices.


title:
Directional flow of solitons with asymmetric potential wells: Soliton
  diode

abstract:
  We study the flow of bright solitons through two asymmetric potential wells.
The scattering of a soliton by certain type of single potential wells, e.g.,
Gaussian or Rosen-Morse, is distinguished by a critical velocity above which
solitons can transmit almost completely and below which solitons can reflect
nearly perfectly. For two such wells in series with certain parameter
combinations, we find that there is an appreciable velocity range for which
solitons can propagate in one direction only. Our study shows that this
directional propagation or diode behavior is due to a combined effect of the
sharp transition in the transport coefficients at the critical velocity and a
slight reduction in the center-of-mass speed of the soliton while it travels
across a potential well.


title: Asymptotic expansion of polyanalytic Bergman kernels

abstract:
  We consider mainly the Hilbert space of bianalytic functions on a given
domain in the plane, square integrable with respect to a weight. We show how to
obtain the asymptotic expansion of the corresponding bianalytic Bergman kernel
for power weights, under the standard condition on those weights. This is known
only in the analytic setting, from the work of e.g. Tian, Yau, Zelditch,
Catlin, et al. We remark that a bianalytic function may be identified with a
vector-valued analytic function, supplied with a locally singular metric on the
vectors. We also apply our findings to two bianalytic Bergman metrics
introduced here.


title: Testing Times for Supersymmetry: Looking Under the Lamp Post

abstract:
  We make a critical study of two highly-constrained models of supersymmetry
--- the constrained minimal supersymmetric standard model (cMSSM), and the
non-universal Higgs mass model (NUHM) --- in the light of the 125-126 GeV Higgs
boson, the first observation of $B_s \to \mu\mu$ at the LHCb, and the updated
$B \to \tau \nu$ branching ratio at BELLE. It turns out that these models are
still allowed by the experimental data, even if we demand that there be a light
stop with mass less than 1.5 TeV. The only significant effects of all these
constraints are to push the mass of the light stop above $\sim 500$ GeV, and to
prefer the universal trilinear coupling $A_0$ to be large and negative. We
calculate the Higgs boson branching ratios to $WW, ZZ, \tau\tau$ and
$\gamma\gamma$ in these models and show that improved experimental limits on
these could put them to the most stringent experimental tests yet.


title:
EasyTime++: A case study of incremental domain-specific language
  development

abstract:
  EasyTime is a domain-specific language (DSL) for measuring time during sports
competitions. A distinguishing feature of DSLs is that they are much more
amenable to change, and EasyTime is no exception in this regard. This paper
introduces two new EasyTime features: classifications of competitors into
categories, and the inclusion of competitions where the number of laps must be
dynamically determined. It shows how such extensions can be incrementally added
into the base-language reusing most of the language specifications. Two case
studies are presented showing the suitability of this approach.


title: The open string McKay correspondence for type A singularities

abstract:
  We formulate a Crepant Resolution Correspondence for open Gromov-Witten
invariants (OCRC) of toric Calabi-Yau orbifolds by viewing the open theories as
sections of Givental's symplectic vector space and the correspondence as a
linear map of Givental spaces which identifies them. We deduce a
Bryan-Graber-type statement for disk invariants and extend it to arbitrary
genus zero topologies in the Hard Lefschetz case. Upon leveraging Iritani's
theory of integral structures to equivariant quantum cohomology, we conjecture
a general form of the symplectomorphism entering the OCRC which arises from a
geometric correspondence at the equivariant K-theory level. We give a complete
proof of this in the case of minimal resolutions of threefold A_n
singularities. Our methods rely on a new description of the equivariant quantum
D-modules underlying the Gromov-Witten theory of this class of targets.


title: Affine Connection Induced from The Horizontal lift on a Cross-section

abstract:
  The main purpose of present paper is to study the affine connection induced
from the horizontal lift on the cross-section determined by a vector field in
Mn with respect to the adapte frame of .


title:
Energy Aware Task Scheduling for Soft Real Time Systems using an
  Analytical Approach for Energy Estimation

abstract:
  Embedded systems have pervaded all walks of our life. With the increasing
importance of mobile embedded systems and flexible applications, considerable
progress in research has been made for power management. Power constraints are
increasingly becoming the critical component of the design specifications of
these systems. It helps in pre-determining the suitable hardware architecture
for the target application. The aim of this paper is to present a technique to
estimate 'pre-run time' and 'power' of a software mapped onto a hardware
system; guaranteeing the compliance of temporal constraints while generating a
schedule of tasks of software. Real time systems must handle several
independent macro-tasks, each represented by a task graph, which includes
communications and precedence constraints. We propose a novel approach for
power estimation of embedded software using the Control Data Flow Graph (CDFG)
or task graph model. This methodology uses an existing Hierarchical Concurrent
Flow Graph (HCFG) technique for the power analysis of the CDFGs. We have
evaluated our technique for energy efficient scheduling over various task graph
benchmarks. The results obtained prove the utility and efficacy of our proposed
approach for power analysis of embedded software. We also present a methodology
to obtain an energy optimal voltage assignment and perform scheduling by taking
advantage of the relaxation in execution time of tasks.


title:
Approximation Algorithms for Stochastic Boolean Function Evaluation and
  Stochastic Submodular Set Cover

abstract:
  Stochastic Boolean Function Evaluation is the problem of determining the
value of a given Boolean function f on an unknown input x, when each bit of x_i
of x can only be determined by paying an associated cost c_i. The assumption is
that x is drawn from a given product distribution, and the goal is to minimize
the expected cost. This problem has been studied in Operations Research, where
it is known as "sequential testing" of Boolean functions. It has also been
studied in learning theory in the context of learning with attribute costs. We
consider the general problem of developing approximation algorithms for
Stochastic Boolean Function Evaluation. We give a 3-approximation algorithm for
evaluating Boolean linear threshold formulas. We also present an approximation
algorithm for evaluating CDNF formulas (and decision trees) achieving a factor
of O(log kd), where k is the number of terms in the DNF formula, and d is the
number of clauses in the CNF formula. In addition, we present approximation
algorithms for simultaneous evaluation of linear threshold functions, and for
ranking of linear functions.
  Our function evaluation algorithms are based on reductions to the Stochastic
Submodular Set Cover (SSSC) problem. This problem was introduced by Golovin and
Krause. They presented an approximation algorithm for the problem, called
Adaptive Greedy. Our main technical contribution is a new approximation
algorithm for the SSSC problem, which we call Adaptive Dual Greedy. It is an
extension of the Dual Greedy algorithm for Submodular Set Cover due to Fujito,
which is a generalization of Hochbaum's algorithm for the classical Set Cover
Problem. We also give a new bound on the approximation achieved by the Adaptive
Greedy algorithm of Golovin and Krause.


title: Estimating a sharp convergence bound for randomized ensembles

abstract:
  When randomized ensembles such as bagging or random forests are used for
binary classification, the prediction error of the ensemble tends to decrease
and stabilize as the number of classifiers increases. However, the precise
relationship between prediction error and ensemble size is unknown in practice.
In the standard case when classifiers are aggregated by majority vote, the
present work offers a way to quantify this convergence in terms of "algorithmic
variance," i.e. the variance of prediction error due only to the randomized
training algorithm. Specifically, we study a theoretical upper bound on this
variance, and show that it is sharp --- in the sense that it is attained by a
specific family of randomized classifiers. Next, we address the problem of
estimating the unknown value of the bound, which leads to a unique twist on the
classical problem of non-parametric density estimation. In particular, we
develop an estimator for the bound and show that its MSE matches optimal
non-parametric rates under certain conditions. (Concurrent with this work, some
closely related results have also been considered in Cannings and Samworth
(2017) and Lopes (2019).)


title: Computing Minimum Cycle Bases in Weighted Partial 2-Trees in Linear Time

abstract:
  We present a linear time algorithm for computing an implicit linear space
representation of a minimum cycle basis (MCB) in weighted partial 2-trees,
i.e., graphs of treewidth two. The implicit representation can be made explicit
in a running time that is proportional to the size of the MCB.
  Our algorithm improves the result of Borradaile, Sankowski, and Wulff-Nilsen
[Min $st$-cut Oracle for Planar Graphs with Near-Linear Preprocessing Time,
FOCS 2010]---which computes for all planar graphs an implicit $O(n \log n)$
space representation of an MCB in $O(n \log^5 n)$ time---by a polylog factor
for the special case of partial 2-trees. Such an improvement was achieved
previously only for outerplanar graphs [Liu and Lu: Minimum Cycle Bases of
Weighted Outerplanar Graphs, IPL 110:970--974, 2010].


title: Groebner bases over fields with valuations

abstract:
  Let K be a field with a valuation and let S be the polynomial ring S:=
K[x_1,..., x_n]. We discuss the extension of Groebner theory to ideals in S,
taking the valuations of coefficients into account, and describe the Buchberger
algorithm in this context. In addition we discuss some implementation and
complexity issues. The main motivation comes from tropical geometry, as
tropical varieties can be defined using these Groebner bases, but we also give
examples showing that the resulting Groebner bases can be substantially smaller
than traditional Groebner bases. In the case K = Q with the p-adic valuation
the algorithms have been implemented in a Macaulay 2 package.


title: Diagonalizing by Fixed-Points

abstract:
  A universal schema for diagonalization was popularized by N. S. Yanofsky
(2003) in which the existence of a (diagonolized-out and contradictory) object
implies the existence of a fixed-point for a certain function. It was shown
that many self-referential paradoxes and diagonally proved theorems can fit in
that schema. Here, we fit more theorems in the universal schema of
diagonalization, such as Euclid's theorem on the infinitude of the primes and
new proofs of Boolos (1997) for Cantor's theorem on the non-equinumerosity of a
set with its powerset. Then, in Linear Temporal Logic, we show the
non-existence of a fixed-point in this logic whose proof resembles the argument
of Yablo's paradox. Thus, Yablo's paradox turns for the first time into a
genuine mathematico-logical theorem in the framework of Linear Temporal Logic.
Again the diagonal schema of the paper is used in this proof, and also it is
shown that G. Priest's inclosure schema (1997) can fit in our universal
diagonal/fixed-point schema. We also show the existence of dominating
(Ackermann-like) functions (which dominate a given countable set of
functions---like primitive recursives) using the schema.


title:
PICARD SODISM, a space telescope to study the Sun from the middle
  ultraviolet to the near infrared

abstract:
  The Solar Diameter Imager and Surface Mapper (SODISM) on board the PICARD
space mission provides wide-field images of the photosphere and chromosphere of
the Sun in five narrow pass bands (centered at 215.0, 393.37, 535.7, 607.1, and
782.2 nm). PICARD is a space mission, which was successfully launched on 15
June 2010 into a Sun synchronous dawn-dusk orbit. It represents a European
asset aiming at collecting solar observations that can serve to estimate some
of the inputs to Earth climate models. The scientific payload consists of the
SODISM imager and of two radiometers, SOVAP (SOlar VAriability PICARD) and
PREMOS (PREcision MOnitor Sensor), which carry out measurements that allow
estimating the Total Solar Irradiance (TSI) and the Solar Spectral Irradiance
(SSI) from the middle ultraviolet to the red. The SODISM telescope monitors
solar activity continuously. It thus produces images that can also feed SSI
reconstruction models. Further, the objectives of SODISM encompass the probing
of the interior of the Sun via helioseismic analysis of observations in
intensity (on the solar disc and at the limb), and via astrometric
investigations at the limb. The latter addresses especially the spectral
dependence of the radial limb shape, and the temporal evolution of the solar
diameter and asphericity. After a brief review of its original science
objectives, this paper presents the detailed design of the SODISM instrument,
its expected performance, and the scheme of its flight operations. Some
observations with SODISM are presented and discussed.


title: Mansuripur's Paradox

abstract:
  A recent article claims that the Lorentz force law is incompatible with
special relativity. We discuss the "paradox" on which this claim is based. The
resolution depends on whether one assumes a "Gilbert" model for the magnetic
dipole (separated monopoles) or the standard "Ampere" model (current loop). The
former was presented in these pages many years ago; the latter requires the
inclusion of "hidden momentum."


title: Cavity Optomechanics

abstract:
  We review the field of cavity optomechanics, which explores the interaction
between electromagnetic radiation and nano- or micromechanical motion. This
review covers the basics of optical cavities and mechanical resonators, their
mutual optomechanical interaction mediated by the radiation pressure force, the
large variety of experimental systems which exhibit this interaction, optical
measurements of mechanical motion, dynamical backaction amplification and
cooling, nonlinear dynamics, multimode optomechanics, and proposals for future
cavity quantum optomechanics experiments. In addition, we describe the
perspectives for fundamental quantum physics and for possible applications of
optomechanical devices.


title:
Monomer distributions and intra-chain collisions of a polymer confined
  to a channel

abstract:
  We study the conformations of a self-avoiding polymer confined to a channel
by computing the cross-sectional distributions of the positions of its
monomers. By means of Monte-Carlo simulations for a self-avoiding,
freely-jointed chain we determine how the cross-sectional distribution for a
given monomer depends on its location in the polymer, and how strongly this
distribution is affected by self avoidance. To this end we analyze how the
frequency of intra-chain collisions between monomers depends on their spatial
position in the channel and on their location within the polymer. We show that
most collisions occur between closely neighboring monomers. As a consequence
the collision probability depends only weakly on the spatial position of the
monomers. Our results explain why the effect of self-avoidance on the monomer
distributions is weaker than predicted by mean-field theory. We discuss the
relevance of our results for studies of DNA conformations in nanofluidic
channels.


title:
On the Behavior of Minimal Free Resolutions of Trivariate Generic
  Monomial Ideals

abstract:
  We will explore some properties of minimal graded free resolutions of $R/I$,
where $R$ is a trivariate polynomial ring over a field and $I$ is a monomial
ideal. Our focus will be to consider a specific form of the resolutions when
$I$ is primary to the homogeneous maximal ideal. We will identify certain
characteristics of the last matrix of these resolutions, and observe
differences in the resolutions for generic ideals in comparison to non-generic
ideals. Finally, we learn how to identify whether $I$ is generic by knowing the
structure of the last matrix in the minimal free resolution of $R/I$.


title: The Death Spiral of T Pyxidis

abstract:
  We report a long campaign to track the 1.8 hr photometric wave in the
recurrent nova T Pyxidis, using the global telescope network of the Center for
Backyard Astrophysics. During 1996-2011, that wave was highly stable in
amplitude and waveform, resembling the orbital wave commonly seen in supersoft
binaries. The period, however, was found to increase on a timescale
P/P-dot=3x10^5 yr. This suggests a mass transfer rate of ~10^-7 M_sol/yr in
quiescence. The orbital signal became vanishingly weak (<0.003 mag) near
maximum light of the 2011 eruption. After it returned to visibility near V=11,
the orbital period had increased by 0.0054(6) %. This is a measure of the mass
ejected in the nova outburst. For a plausible choice of binary parameters, that
mass is at least 3x10^-5 M_sol, and probably more. This represents >300 yr of
accretion at the pre-outburst rate, but the time between outbursts was only 45
yr. Thus the erupting white dwarf seems to have ejected at least 6x more mass
than it accreted. If this eruption is typical, the white dwarf must be eroding,
rather than growing, in mass -- dashing the star's hopes of ever becoming
famous via a supernova explosion. Instead, it seems likely that the binary
dynamics are basically a suicide pact between the eroding white dwarf and the
low-mass secondary, excited and rapidly whittled down, probably by the white
dwarf's EUV radiation.


title:
Centrality dependence of $\rm \mathbf \pi$, K, p production in Pb-Pb
  collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV

abstract:
  In this paper measurements are presented of $\rm \pi$$^+$, $\rm \pi$$^-$,
K$^+$, K$^-$, p and $\overline{\rm p}$ production at mid-rapidity < 0.5, in
Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 2.76$ TeV as a function of centrality.
The measurement covers the transverse momentum ($p_{\rm T}$) range from 100,
200, 300 MeV/$c$ up to 3, 3, 4.6 GeV/$c$, for $\rm\pi$, K, and p respectively.
The measured $p_{\rm T}$ distributions and yields are compared to expectations
based on hydrodynamic, thermal and recombination models. The spectral shapes of
central collisions show a stronger radial flow than measured at lower energies,
which can be described in hydrodynamic models. In peripheral collisions, the
$p_{\rm T}$ distributions are not well reproduced by hydrodynamic models.
Ratios of integrated particle yields are found to be nearly independent of
centrality. The yield of protons normalized to pions is a factor ~1.5 lower
than the expectation from thermal models.


title:
New Symbolic Algorithms For Solving A General Bordered Tridiagonal
  Linear System

abstract:
  In this paper, the author present reliable symbolic algorithms for solving a
general bordered tridiagonal linear system. The first algorithm is based on the
LU decomposition of the coefficient matrix and the computational cost of it is
O(n). The second is based on The Sherman-Morrison-Woodbury formula. The
algorithms are implementable to the Computer Algebra System (CAS) such as
MAPLE, MATLAB and MATHEMATICA. Three examples are presented for the sake of
illustration.


title: Best approximation by diagonal compact operators

abstract:
  We study the existence and characterization properties of compact Hermitian
operators C on a separable Hilbert space H such that ||C|| is less or equal
than || C + D ||, for all D in D(K(H)). This property is equivalent to || C ||
= min{||C+D||: D in D(K(H))} = dist (C,D(K(H))), where D(K(H)) denotes the
space of compact diagonal operators in a fixed base of H and ||.|| is the
operator norm. We also exhibit a positive trace class operator that fails to
attain the minimum in a compact diagonal.


title: Nanoelectromechanics of shuttle devices

abstract:
  A single-electron tunneling (SET) device with a nanoscale central island that
can move with respect to the bulk source- and drain electrodes allows for a
nanoelectromechanical (NEM) coupling between the electrical current through the
device and mechanical vibrations of the island. Although an electromechanical
"shuttle" instability and the associated phenomenon of single-electron
shuttling were predicted more than 15 years ago, both theoretical and
experimental studies of NEM-SET structures are still carried out. New
functionalities based on quantum coherence, Coulomb correlations and coherent
electron-spin dynamics are of particular current interest. In this article we
present a short review of recent activities in this area.


title:
Operator content of real-space entanglement spectra at conformal
  critical points

abstract:
  We provide numerical evidence that the low-lying part of the entanglement
spectrum of a real-space block (i.e. a single interval) of a one-dimensional
quantum many body system at a conformal critical point corresponds to the
energy spectrum of a boundary conformal field theory (CFT). This correspondence
allows to uncover a subset of the operator content of a conformal field theory
by inspection of the entanglement spectrum of a single wave function, thus
providing important information on a CFT beyond its central charge. As a
practical application we show that for many systems described by a compactified
boson CFT, one can infer the compactification radius (governing e.g. the power
law decay of correlation functions) of the theory in a simple way based on the
entanglement spectrum.


title: Multivariate Temporal Dictionary Learning for EEG

abstract:
  This article addresses the issue of representing electroencephalographic
(EEG) signals in an efficient way. While classical approaches use a fixed Gabor
dictionary to analyze EEG signals, this article proposes a data-driven method
to obtain an adapted dictionary. To reach an efficient dictionary learning,
appropriate spatial and temporal modeling is required. Inter-channels links are
taken into account in the spatial multivariate model, and shift-invariance is
used for the temporal model. Multivariate learned kernels are informative (a
few atoms code plentiful energy) and interpretable (the atoms can have a
physiological meaning). Using real EEG data, the proposed method is shown to
outperform the classical multichannel matching pursuit used with a Gabor
dictionary, as measured by the representative power of the learned dictionary
and its spatial flexibility. Moreover, dictionary learning can capture
interpretable patterns: this ability is illustrated on real data, learning a
P300 evoked potential.


title: St\"uckelberg Fields on the Effective p-brane

abstract:
  We demonstrate the one-to-one correspondence between reparametrization
invariant effective actions for relativistic p-branes in flat target space and
effective actions for transverse brane perturbations with non-linearly realized
Poincar\'e symmetry. Starting with an action with non-linearly realized
symmetry we construct the corresponding reparametrization invariant action by
introducing St\"uckelberg fields. They combine with the transverse modes to
form a Lorentz vector. The manifest Lorentz symmetry of the reparametrization
invariant action follows directly from the non-linearly realized Lorentz
symmetry of the initial action in terms of the physical modes.


title:
A cluster algebra approach to q-characters of Kirillov-Reshetikhin
  modules

abstract:
  We describe a cluster algebra algorithm for calculating q-characters of
Kirillov-Reshetikhin modules for any untwisted quantum affine algebra. This
yields a geometric q-character formula for tensor products of
Kirillov-Reshetikhin modules. In simply laced type this formula extends
Nakajima's formula for q-characters of standard modules in terms of homology of
graded quiver varieties.


title:
Anharmonic vibrational properties in periodic systems: energy,
  electron-phonon coupling, and stress

abstract:
  A unified approach is used to study vibrational properties of periodic
systems with first-principles methods and including anharmonic effects. Our
approach provides a theoretical basis for the determination of phonon-dependent
quantities at finite temperatures. The low-energy portion of the
Born-Oppenheimer energy surface is mapped and used to calculate the total
vibrational energy including anharmonic effects, electron-phonon coupling, and
the vibrational contribution to the stress tensor. We report results for the
temperature dependence of the electronic band gap and the linear coefficient of
thermal expansion of diamond, lithium hydride, and lithium deuteride.


title: Absence of scalar hair in scalar-tensor gravity

abstract:
  Stationary, asymptotically flat black holes in scalar-tensor theories of
gravity are studied. It is shown that such black holes have no scalar hair and
are the same as in General Relativity.


title:
Hall response of interacting bosonic atoms in strong gauge fields: from
  condensed to FQH states

abstract:
  Interacting bosonic atoms under strong gauge fields undergo a series of phase
transitions that take the cloud from a simple Bose-Einstein condensate all the
way to a family of fractional-quantum-Hall-type states [M. Popp, B. Paredes,
and J. I. Cirac, Phys. Rev. A 70, 053612 (2004)]. In this work we demonstrate
that the Hall response of the atoms can be used to locate the phase transitions
and characterize the ground state of the many-body state. Moreover, the same
response function reveals within some regions of the parameter space, the
structure of the spectrum and the allowed transitions to excited states. We
verify numerically these ideas using exact diagonalization for a small number
of atoms, and provide an experimental protocol to implement the gauge fields
and probe the linear response using a periodically driven optical lattice.
Finally, we discuss our theoretical results in relation to recent experiments
with condensates in artificial magnetic fields [ L. J. LeBlanc, K.
Jimenez-Garcia, R. A. Williams, M. C. Beeler, A. R. Perry, W. D. Phillips, and
I. B. Spielman, Proc. Natl. Acad. Sci. USA 109, 10811 (2012)] and we analyze
the role played by vortex states in the Hall response.


title: Quantal corrections to mean-field dynamics including pairing

abstract:
  Extending the stochastic mean-field model by including pairing, an approach
is proposed for describing evolutions of complex many-body systems in terms of
an ensemble of Time-Dependent Hartree-Fock Bogoliubov trajectories which is
determined by incorporating fluctuations in the initial state. Non-linear
evolution of the initial fluctuations provides an approximate description of
quantal correlations and fluctuations of collective observables. Since the
initial-state fluctuations break the particle-number symmetry, the dynamical
description in which pairing correlations play a crucial role is greatly
improved as compare to the mean-field evolution. The approach is illustrated
for a system of particles governed by a pairing Hamiltonian.

categories: nucl-th cond-mat.str-el nucl-ex quant-ph


title:
Charge carrier dynamics in bulk MoS2 crystal studied by transient
  absorption microscopy

abstract:
  We report a transient absorption microscopy study of charge carrier dynamics
in bulk MoS2 crystals at room temperature. Charge carriers are injected by
interband absorption of a 555-nm pulse, and probed by measuring differential
reflection of a time-delayed and spatially scanned 660-nm pulse. We find an
intervalley transfer time of about 0.35 ps, an energy relaxation time of hot
carriers on the order of 50 ps, and a carrier lifetime of 180 ps. By monitoring
the spatiotemporal dynamics of carriers, we obtained a diffusion coefficient of
thermalized electrons of 4.2 cm2/s, corresponding to a mobility of 170 cm2/Vs.
We also observed a time-varying diffusion coefficient of hot carriers.


title:
Soft lags in neutron star kHz Quasi Periodic Oscillations: evidence for
  reverberation?

abstract:
  High frequency soft reverberation lags have now been detected from stellar
mass and super massive black holes. Their interpretation involves reflection of
a hard source of photons onto an accretion disk, producing a delayed reflected
emission, with a time lag consistent with the light travel time between the
irradiating source and the disk. Independently of the location of the clock,
the kHz Quasi-Periodic Oscillation (QPO) emission is thought to arise from the
neutron star boundary layer. Here, we search for the signature of reverberation
of the kHz QPO emission, by measuring the soft lags and the lag energy spectrum
of the lower kHz QPOs from 4U1608-52. Soft lags, ranging from ~15 to ~40
microseconds, between the 3-8 keV and 8-30 keV modulated emissions are detected
between 565 and 890 Hz. The soft lags are not constant with frequency and show
a smooth decrease between 680 Hz and 890 Hz. The broad band X-ray spectrum is
modeled as the sum of a disk and a thermal comptonized component, plus a broad
iron line, expected from reflection. The spectral parameters follow a smooth
relationship with the QPO frequency, in particular the fitted inner disk radius
decreases steadily with frequency. Both the bump around the iron line in the
lag energy spectrum, and the consistency between the lag changes and the
inferred changes of the inner disk radius, from either spectral fitting or the
QPO frequency, suggest that the soft lags may indeed involve reverberation of
the hard pulsating QPO source on the disk.


title: First-principles energetics of water: a many-body analysis

abstract:
  Standard forms of density-functional theory (DFT) have good predictive power
for many materials, but are not yet fully satisfactory for solid, liquid and
cluster forms of water. We use a many-body separation of the total energy into
its 1-body, 2-body (2B) and beyond-2-body (B2B) components to analyze the
deficiencies of two popular DFT approximations. We show how machine-learning
methods make this analysis possible for ice structures as well as for water
clusters. We find that the crucial energy balance between compact and extended
geometries can be distorted by 2B and B2B errors, and that both types of
first-principles error are important.


title: Inclusion of matter in inhomogeneous loop quantum cosmology

abstract:
  We study the hybrid quantization of the linearly polarized Gowdy $T^3$ model
with a massless scalar field with the same symmetries as the metric. For
simplicity, we quantize its restriction to the model with local rotational
symmetry. Using this hybrid approach, the homogeneous degrees of freedom of the
geometry are quantized \`a la loop, leading to the resolution of the
cosmological singularity. A Fock quantization is employed both for the matter
and the gravitational inhomogeneities. Owing to the inclusion of the massless
scalar field this system allows us to modelize flat Friedmann-Robertson-Walker
cosmologies filled with inhomogeneities propagating in one direction, providing
a perfect scenario to study the quantum back-reaction of the inhomogeneities on
the polymeric homogeneous and isotropic background.


title: Tau-functions for Quiver Gauge Theories

abstract:
  The prepotentials for the quiver supersymmetric gauge theories are defined as
quasiclassical tau-functions, depending on two different sets of variables: the
parameters of the UV gauge theory or the bare compexified couplings, and the
vacuum condensates of the theory in IR. The bare couplings are introduced as
periods on the UV base curve, and the consistency of corresponding gradient
formulas for the tau-functions is proven using the Riemann bilinear relations.
It is shown, that dependence of generalised prepotentials for the quiver gauge
theories upon the bare couplings turns to coincide with the corresponding
formulas for the derivatives of tau-functions for the isomonodromic
deformations. Computations for the SU(2) quiver gauge theories with bi- and
tri-fundamental matter are performed explicitly and analysed in the context of
4d/2d correspondence.


title: New constraint on the existence of the mu+-> e+ gamma decay

abstract:
  The analysis of a combined data set, totaling 3.6 \times 10^14 stopped muons
on target, in the search for the lepton flavour violating decay mu^+ -> e^+
gamma is presented. The data collected by the MEG experiment at the Paul
Scherrer Institut show no excess of events compared to background expectations
and yield a new upper limit on the branching ratio of this decay of 5.7 \times
10^-13 (90% confidence level). This represents a four times more stringent
limit than the previous world best limit set by MEG.


title:
Fermionic vacuum polarization by a cosmic string in anti-de Sitter
  spacetime

abstract:
  In this paper we investigate the fermionic condensate (FC) and the vacuum
expectation value (VEV) of the energy-momentum tensor, associated with a
massive fermionic field, induced by the presence of a cosmic string in the
anti-de Sitter (AdS) spacetime. In order to develop this analysis we construct
the complete set of normalized eigenfunctions in the corresponding spacetime.
We consider a special case of boundary conditions on the AdS boundary, when the
MIT bag boundary condition is imposed on the field operator at a finite
distance from the boundary, which is then taken to zero. The FC and the VEV of
the energy-momentum tensor are decomposed into the pure AdS and string-induced
parts. Because the analysis of one-loop quantum effects in the AdS spacetime
has been developed in the literature, here we are mainly interested to
investigate the influence of the cosmic string on the VEVs. The string-induced
part in the VEV of the energy-momentum tensor is diagonal and the axial and
radial stresses are equal to the energy density. For points near the string,
the effects of the curvature are subdominant and to leading order, the VEVs
coincide with the corresponding VEVs for the cosmic string in Minkowski bulk.
At large proper distances from the string, the decay of the VEVs show a
power-law dependence of the distance for both massless and massive fields. This
is in contrast to the case of Minkowski bulk where, for a massive field, the
string-induced parts decay exponentially.


title:
Chaos in large-amplitude pulsators: application to the beta Cep star
  HD180642

abstract:
  The CoRoT observations of the beta Cephei star HD180642 uncover an
unexpectedly rich frequency spectrum, in addition to several heat-driven modes.
So far, two processes have been proposed to explain this behaviour: the
presence of stochastic oscillations, and the excitation of time-dependent
frequencies by nonlinear resonance.
  I argue for a third explanation for the observations, in the form of chaos
due to the nonlinear behaviour of the dominant radial mode.
  The long-term frequency stability of the dominant radial mode is studied
using archival data spanning roughly 20 years. Nonlinear time series analysis
techniques are applied to the CoRoT observations, and the observations are
compared with simulations of a simple nonlinear oscillator.
  I show that chaos offers one single explanation for many of the observed
features, such as the structure in the autocorrelation of the power spectrum,
the long-term frequency shift, the power excess and the wide range of
frequencies in the power spectrum. However, the mixture of opacity-driven
linear oscillations and nonlinear oscillations complicate the nonlinear time
series analysis techniques.


title:
The specific heat and the radial thermal expansion of bundles of
  single-walled carbon nanotubes

abstract:
  The specific heat at constant pressure of bundles of single-walled carbon
nanotubes closed at their ends has been investigated in a temperature interval
of 2-120 K. It is found that the curve of heat capacity has features near 5,
36, 80, and 100 K. The experimental results on the heat capacity and the radial
thermal expansion coefficient of bundles of SWNTs oriented perpendicular to the
sample axis have been compared. It is found that the curves of the heat
capacity and the radial thermal expansion coefficient exhibit a similar
temperature behavior above 10 K. The temperature dependence of the Gruneisen
coefficient has been calculated. The curve of the Gruneisen coefficient also
has a feature near 36 K. Above 36 K the Gruneisen coefficient is practically
independent of temperature. Below 36 K the Gruneisen coefficient decreases
monotonically with lowering temperature and becomes negative below 6 K.


title:
Improving the neutrino mass hierarchy identification with inelasticity
  measurement in PINGU and ORCA

abstract:
  Multi-megaton scale under ice and underwater detectors of atmospheric
neutrinos with few GeV's energy threshold (PINGU, ORCA) open up new
possibilities in the determination of neutrino properties, and in particular
the neutrino mass hierarchy. With a dense array of optical modules it will be
possible to determine the inelasticity, $y$, of the charged current $\nu_\mu$
events in addition to the neutrino energy $E_\nu$ and the muon zenith angle
$\theta_\mu$. The discovery potential of the detectors will substantially
increase with the measurement of $y$. It will enable (i) a partial separation
of the neutrino and antineutrino signals; (ii) a better reconstruction of the
neutrino direction; (iii) the reduction of the neutrino parameters degeneracy;
(iv) a better control of systematic uncertainties; (v) a better identification
of the $\nu_\mu$ events. It will improve the sensitivity to the CP-violation
phase. The three dimensional, $(E_\nu, \theta_\mu, y)$, $\nu_\mu-$oscillograms
with the kinematical as well as the experimental smearing are computed. We
present the asymmetry distributions in the $E_\nu - \theta_\mu$ plane for
different intervals of $y$ and study their properties. We show that the
inelasticity information reduces the effect of degeneracy of parameters by 30%.
With the inelasticity, the total significance of establishing mass hierarchy
may increase by 20% - 50%, thus effectively increasing the volume of the
detector by factor 1.5 - 2.


title: Black Hole Monodromy and Conformal Field Theory

abstract:
  The analytic structure of solutions to the Klein-Gordon equation in a black
hole background, as represented by monodromy data, is intimately related to
black hole thermodynamics. It encodes the "hidden conformal symmetry" of a
non-extremal black hole, and it explains why features of the inner event
horizon appear in scattering data such as greybody factors. This indicates that
hidden conformal symmetry is generic within a universality class of black
holes.


title: Decidability of the Elementary Theory of a Torsion-Free Hyperbolic Group

abstract:
  Let G be a torsion free hyperbolic group. We prove that the elementary theory
of G is decidable and admits an effective quantifier elimination to boolean
combination of AE-formulas. The existence of such quantifier elimination was
previously proved by Sela.


title: A Phase Transition in a Quenched Amorphous Ferromagnet

abstract:
  Quenched thermodynamic states of an amorphous ferromagnet are studied. The
magnet is a countable collection of point particles chaotically distributed
over $\mathbb{R}^d$, $d\geq 2$. Each particle bears a real-valued spin with
symmetric a priori distribution; the spin-spin interaction is pair-wise and
attractive. Two spins are supposed to interact if they are neighbors in the
graph defined by a homogeneous Poisson point process. For this model, we prove
that with probability one: (a) quenched thermodynamic states exist; (b) they
are multiple if the particle density (i.e., the intensity of the underlying
point process) and the inverse temperature are big enough; (c) there exist
multiple quenched thermodynamic states which depend on the realizations of the
underlying point process in a measurable way.


title: A new perspective on early cosmology

abstract:
  We present a new perspective on early cosmology based on Loop Quantum
Gravity. We use projected spinnetworks, coherent states and spinfoam
techniques, to implement a quantum reduction of the full Kinematical Hilbert
space of LQG, suitable to describe inhomogeneous cosmological models. Some
preliminary results on the solutions of the Scalar constraint of the reduced
theory are also presented.


title:
Search for the standard model Higgs boson produced in association with a
  top-quark pair in pp collisions at the LHC

abstract:
  A search for the standard model Higgs boson produced in association with a
top-quark pair is presented using data samples corresponding to an integrated
luminosity of 5.0 inverse femtobarns (5.1 inverse femtobarns) collected in pp
collisions at the center-of-mass energy of 7 TeV (8 TeV). Events are considered
where the top-quark pair decays to either one lepton+jets (t tbar to ell nu q
q' b bbar) or dileptons (t tbar to ell(+) nu ell(-) nu b bbar), ell being an
electron or a muon. The search is optimized for the decay mode H to b bbar. The
largest background to the t tbar H signal is top-quark pair production with
additional jets. Artificial neural networks are used to discriminate between
signal and background events. Combining the results from the 7 TeV and 8 TeV
samples, the observed (expected) limit on the cross section for Higgs boson
production in association with top-quark pairs for a Higgs boson mass of 125
GeV is 5.8 (5.2) times the standard model expectation.


title: Electric polarization in correlated insulators

abstract:
  We derive a formula for the electric polarization of interacting insulators,
expressed in terms of the full Green's and vertex functions. We exemplify this
method in the half-filled ionic Hubbard model treated within dynamical mean
field theory (DMFT). The electric polarization of a correlated band insulator
is determined by the interplay of ionicity and covalency, and both quantities
are renormalized by the electron-electron interactions. We introduce
quasiparticle approximation to the exact equation for the polarization, and
compare the results of this approximation with those of the exact DMFT
formulation and of static mean field theories such as the LDA+ U. The latter
overestimates the electronic contribution to the electric polarization when the
quasiparticle weight of the active bands is very small.


title:
Two and three descent for elliptic curves associated with perfect
  cuboids

abstract:
  A rational perfect cuboid is a rectangular parallelepiped whose edges and
face diagonals are given by rational numbers and whose space diagonal is equal
to unity. Recently it was shown that the Diophantine equations describing such
a cuboid lead to a couple of parametric families of elliptic curves. Two and
three descent methods for calculating their ranks are discussed in the present
paper. The elliptic curves in each parametric family are subdivided into two
subsets admitting 2-descent and 3-descent methods respectively.


title: Bibliometrics for Internet Media: Applying the h-Index to YouTube

abstract:
  The h-index can be a useful metric for evaluating a person's output of
Internet media. Here we advocate and demonstrate adaption of the h-index and
the g-index to the top video content creators on YouTube. The h-index for
Internet video media is based on videos and their view counts. The index h is
defined as the number of videos with >= h*10^5 views. The index g is defined as
the number of videos with >= g*10^5 views on average. When compared to a video
creator's total view count, the h-index and g-index better capture both
productivity and impact in a single metric.


title: The hypercomplex equations for fermion interaction description

abstract:
  Equations are proposed for the description of the fermion interaction via
massive and massless bosons. These equations lead to the propagators which
maintain theory renormalization. These equations are also invariant with
respect to the limited calibration transformations. Such an approach leads to
the possibility of describing fermion interaction via massive bosons and not
referring to the spontaneous symmetry violation.


title:
Localization of metallicity and magnetic properties of graphene and of
  graphene nanoribbons doped with boron clusters

abstract:
  As a possible way of modifying the intrinsic properties of graphene we study
the doping of graphene by embedded boron clusters with density functional
theory. Cluster doping is technologically relevant as the cluster implantation
technique can be readily applied to graphene. We find that B7 clusters embedded
into graphene and graphene nanoribbons are structurally stable and locally
metallize the system. This is done both by the reduction of the Fermi energy
and by the introduction of boron states near the Fermi level. A linear chain of
boron clusters forms a metallic "wire" inside the graphene matrix. In a zigzag
edge graphene nanoribbon the cluster-related states tend to hybridize with the
edge and bulk states. The magnetism in boron doped graphene systems is
generally very weak. The presence of boron clusters weakens the edge magnetism
in zigzag edge graphene nanoribbon, rather than making the system appropriate
for spintronics. Thus the doping of graphene with the cluster implantation
technique might be a viable technique to locally metallize graphene without
destroying its attractive bulk properties.


title:
Accretion Rates for T Tauri Stars Using Nearly Simultaneous Ultraviolet
  and Optical Spectra

abstract:
  We analyze the accretion properties of 21 low mass T Tauri stars using a
dataset of contemporaneous near ultraviolet (NUV) through optical observations
obtained with the Hubble Space Telescope Imaging Spectrograph (STIS) and the
ground based Small and Medium Aperture Research Telescope System (SMARTS), a
unique dataset because of the nearly simultaneous broad wavelength coverage.
Our dataset includes accreting T Tauri stars (CTTS) in Taurus, Chamaeleon I,
$\eta$ Chamaeleon and the TW Hydra Association. For each source we calculate
the accretion rate by fitting the NUV and optical excesses above the
photosphere, produced in the accretion shock, introducing multiple accretion
components characterized by a range in energy flux (or density) for the first
time. This treatment is motivated by models of the magnetospheric geometry and
accretion footprints, which predict that high density, low filling factor
accretion spots co-exist with low density, high filling factor spots. By
fitting the UV and optical spectra with multiple accretion components, we can
explain excesses which have been observed in the near infrared. Comparing our
estimates of the accretion rate to previous estimates, we find some
discrepancies; however, they may be accounted for when considering assumptions
for the amount of extinction and variability in optical spectra. Therefore, we
confirm many previous estimates of the accretion rate. Finally, we measure
emission line luminosities from the same spectra used for the accretion rate
estimates, to produce correlations between accretion indicators (H$\beta$, Ca
II K, C II] and Mg II) and accretion properties obtained simultaneously.


title: Little Z' Models

abstract:
  We propose a new class of models called Little Z' models in order to reduce
the fine-tuning due to the current experimental limits on the Z' mass in E_6
inspired supersymmetric models, where the Higgs doublets are charged under the
extra U(1)' gauge group. The proposed Little Z' models allow a lower mass Z'
due to the spontaneously broken extra U(1)' gauge group having a reduced gauge
coupling. We show that reducing the value of the extra gauge coupling relaxes
the experimental limits, leading to the possibility of low mass Z' resonances,
for example down to 200 GeV, which may yet appear in LHC searches. Although the
source of tree level fine-tuning due to the Z' mass is reduced in Little Z'
models, it typically does so at the expense of increasing the vacuum
expectation value of the U(1)'-breaking standard model singlet field, reducing
the fine-tuning to similar levels to that in the Minimal Supersymmetric
Standard Model.


title: Spin-enhanced organic bulk heterojunction photovoltaic solar cells

abstract:
  Recently, much effort has been devoted to improve the efficiency of organic
photovoltaic solar cells based on blends of donors and acceptors molecules in
bulk heterojunction architecture. One of the major losses in organic
photovoltaic devices has been recombination of polaron pairs at the
donor/acceptor domain interfaces. Here, we present a novel method to suppress
polaron pair recombination at the donor/acceptor domain interfaces and thus
improve the organic photovoltaic solar cell efficiency, by doping the device
active layer with spin 1/2 radical galvinoxyl. At an optimal doping level of 3
wt%, the efficiency of a standard
poly(3-hexylthiophene)/1-(3-(methoxycarbonyl)propyl)-1-1-phenyl)(6,6)C61 solar
cell improves by 18%. A spin-flip mechanism is proposed and supported by
magneto-photocurrent measurements, as well as by density functional theory
calculations in which polaron pair recombination rate is suppressed by resonant
exchange interaction between the spin 1/2 radicals and charged acceptors, which
convert the polaron pair spin state from singlet to triplet.


title: Spinon-Phonon Interaction in Algebraic Spin Liquids

abstract:
  Motivated by a search for experimental probes to access the physics of
fractionalized excitations called spinons in a spin liquids, we study the
interaction of spinons with lattice vibrations. We consider the case of
algebraic spin liquid, when spinons have fermionic statistics and a Dirac-like
dispersion. We establish the general procedure for deriving spinon-phonon
interactions which is based on a symmetry considerations. The procedure is
illustrated for four different algebraic spin liquids: pi-flux and
staggered-flux phases on a square lattice, pi-flux phase on a kagome lattice,
and zero flux phase on a honeycomb lattice. Although the low energy description
is similar for all these phases, different underlying symmetry group leads to a
distinct form of spinon-phonon interaction Hamiltonian. The explicit form of
the spinon-phonon interaction is used to estimate the attenuation of ultrasound
in an algebraic spin liquid. The perspectives of the sound attenuation as probe
of spinons are discussed.


title:
Perturbed Laguerre Unitary Ensembles, Painlev\'e V and Information
  Theory

abstract:
  In this review, we investigate a key information-theoretic performance metric
in multiple-antenna wireless communications, the so-called outage probability.
This quantity may be expressed in terms of a moment generating function, for
which we present two separate integral representations, one involving a
particular $\sigma$-form of Painlev\'e V. We also present a representation
involving a non-linear second order difference equation.


title: Perfect Impedance-Matched Isolators and Unidirectional Absorbers

abstract:
  A broad-band reflectionless channel which supports unidirectional wave
propagation originating from the interplay between gyrotropic elements and
symmetrically placed gain and loss constituents is proposed. Interchange of the
active elements together with a gyrotropic inversion turns the same structure
to a unidirectional absorber where incoming waves from a specific direction are
annihilated. When disorder is introduced asymmetric Anderson localization is
found. Realizations of such multi-functional architectures in the frame of
electronic and photonic circuitry are discussed.


title:
Hybrid Maximum Likelihood Modulation Classification Using Multiple
  Radios

abstract:
  The performance of a modulation classifier is highly sensitive to channel
signal-to-noise ratio (SNR). In this paper, we focus on amplitude-phase
modulations and propose a modulation classification framework based on
centralized data fusion using multiple radios and the hybrid maximum likelihood
(ML) approach. In order to alleviate the computational complexity associated
with ML estimation, we adopt the Expectation Maximization (EM) algorithm. Due
to SNR diversity, the proposed multi-radio framework provides robustness to
channel SNR. Numerical results show the superiority of the proposed approach
with respect to single radio approaches as well as to modulation classifiers
using moments based estimators.


title:
Statistical Study of Deep Sub-Micron Dual-Gated Field-Effect Transistors
  on Monolayer CVD Molybdenum Disulfide Films

abstract:
  Monolayer Molybdenum Disulfide (MoS2) with a direct band gap of 1.8 eV is a
promising two-dimensional material with a potential to surpass graphene in next
generation nanoelectronic applications. In this letter, we synthesize monolayer
MoS2 on Si/SiO2 substrate via chemical vapor deposition (CVD) method and
comprehensively study the device performance based on dual-gated MoS2
field-effect transistors. Over 100 devices are studied to obtain a statistical
description of device performance in CVD MoS2. We examine and scale down the
channel length of the transistors to 100 nm and achieve record high drain
current of 62.5 mA/mm in CVD monolayer MoS2 film ever reported. We further
extract the intrinsic contact resistance of low work function metal Ti on
monolayer CVD MoS2 with an expectation value of 175 {\Omega}.mm, which can be
significantly decreased to 10 {\Omega}.mm by appropriate gating. Finally,
field-effect mobilities ({\mu}FE) of the carriers at various channel lengths
are obtained. By taking the impact of contact resistance into account, an
average and maximum intrinsic {\mu}FE is estimated to be 13.0 and 21.6 cm2/Vs
in monolayer CVD MoS2 films, respectively.


title:
Integrating hidden information which is observed and the observer
  information regularities

abstract:
  Bayesian integral functional measure of entropy-uncertainty (EF) on
trajectories of Markov multi-dimensional diffusion process is cutting off by
interactive impulses (controls). Each cutoff minimax of EF superimposes and
entangles conjugated fractions in microprocess, enclosing the captured entropy
fractions as source of an information unit. The impulse step-up action launches
the unit formation and step-down action finishes it and brings energy from the
interactive jump. This finite jump transfers the entangled entropy from
uncertain Yes-logic to the certain-information No-logic information unit whose
measuring at end of the cut kills final entropy-uncertainty and limits unit.
The Yes-No logic holds Bit Participator creating elementary information
observer without physical pre-law. Cooperating two units in doublet and an
opposite directional information unit in triplet forms minimal stable
structure. Information path functional (IPF) integrates multiple hidden
information contributions along the cutting process correlations in information
units of cooperating doublets-triplets, bound by free information, and enfolds
the sequence of enclosing triplet structures in the information network (IN)
that sequentially decreases the entropy and maximizes information. The IN bound
triplets release free information rising information forces enable attracting
new information unit and ordering it. While IPF collects the information units,
the IN performs logical computing using doublet-triplet code. The IN different
levels unite logic of quantum micro- and macro- information processes,
composing quantum and/or classical computation.


title:
Threefold Reduction in Thermal Conductivity of Vycor Glass Due to
  Adsorption of Liquid 4He

abstract:
  We report thermal conductivity measurements of porous Vycor glass when it is
empty and when the pores are filled with helium between 0.06 and 0.5 K. The
filling of liquid 3He and liquid 4He inside the Vycor pores brings about
respectively two and three fold reduction of the thermal conductivity as
compared with empty Vycor. This dramatic reduction of thermal conductivity, not
seen with solid 3He and 4He in the pores, is the consequence of hydrodynamic
sound modes in liquid helium that greatly facilitate the quantum tunneling of
the two-level systems (TLS) in Vycor and enhance the scattering of the thermal
phonons in the silica network.


title: CP violation in neutrino-photon scattering

abstract:
  It is shown that effects of CP violation arise in neutrino-photon scattering.
Several CP-violating $\nu\gamma$ reactions are considered within the Standard
Model and predictions for some observables are made. It is emphasized that
neutrino-photon scattering may provide an experimental tool for testing the
scale dependence of CP violation.


title:
Note on Undecidability of Bisimilarity for Second-Order Pushdown
  Processes

abstract:
  Broadbent and G\"oller (FSTTCS 2012) proved the undecidability of
bisimulation equivalence for processes generated by epsilon-free second-order
pushdown automata. We add a few remarks concerning the used proof technique,
called Defender's forcing, and the related undecidability proof for first-order
pushdown automata with epsilon-transitions (Jan\v{c}ar and Srba, JACM 2008).