title:
The Directional Dependence of Apertures, Limits and Sensitivity of the
  Lunar Cherenkov Technique to a UHE Neutrino Flux

abstract:
  We use computer simulations to obtain the directional-dependence of the lunar
Cherenkov technique for ultra-high energy (UHE) neutrino detection. We
calculate the instantaneous effective area of past lunar Cherenkov experiments
as a function of neutrino arrival direction, and hence the
directional-dependence of the combined limit imposed by GLUE and the experiment
at Parkes.
  We also determine the directional dependence of the aperture of future
planned experiments with ATCA, ASKAP and the SKA to a UHE neutrino flux, and
calculate the potential annual exposure to astronomical objects as a function
of angular distance from the lunar trajectory through celestial coordinates.


title:
Quantitative Spectroscopy of 24 A supergiants in the Sculptor galaxy NGC
  300: Flux weighted gravity luminosity relationship, metallicity and
  metallicity gradient

abstract:
  A quantitative spectral analysis of 24 A supergiants in the Sculptor Group
spiral galaxy NGC 300 at a distance of 1.9 Mpc is presented. A new method is
introduced to analyze low resolution (~5 AE) spectra, which yields
metallicities accurate to 0.2 dex including the uncertainties arising from the
errors in Teff (5%) and log g (0.2 dex). For the first time the stellar
metallicity gradient based on elements such as titanium and iron in a galaxy
beyond the Local Group is investigated. Solar metallicity is measured in the
center and 0.3 solar in the outskirts and a logarithmic gradient of -0.08
dex/kpc. An average reddening of E(B-V)~0.12 mag is obtained, however with a
large variation from 0.07 to 0.24 mag. We also determine stellar radii,
luminosities and masses and discuss the evolutionary status. Finally, the
observed relationship between absolute bolometric magnitudes M_{bol} and flux
weighted gravities g_{F} = g/Teff^4 is investigated. At high temperatures the
strengths of the Balmer lines depends solely on the flux-weighted gravity,
which allows a precise direct determination of log g_{F} with an accuracy of
0.05 to 0.1 dex. We find a tight relationship between M_{bol} and log g_{F} in
agreement with stellar evolution theory. Combining these new results with
previous work on Local Group galaxies we obtain a new flux weighted gravity
luminosity relationship (FGLR), which is very well defined and appears to be an
excellent alternative tool to determine distances to galaxies.


title: Free products, cyclic homology, and the Gauss-Manin connection

abstract:
  We present a new approach to cyclic homology that does not involve the Connes
differential and is based on a `noncommutative equivariant de Rham complex' of
an associative algebra. The differential in that complex is a sum of the
Karoubi-de Rham differential, which replaces the Connes differential, and
another operation analogous to contraction with a vector field. As a byproduct,
we give a simple explicit construction of the Gauss-Manin connection,
introduced earlier by E. Getzler, on the relative cyclic homology of a flat
family of associative algebras over a central base ring.
  We introduce and study `free-product deformations' of an associative algebra,
a new type of deformation over a not necessarily commutative base ring. Natural
examples of free-product deformations arise from preprojective algebras and
group algebras for compact surface groups.


title: Extragalactic Stellar Astronomy with the Brightest Stars in the Universe

abstract:
  A supergiants are objects in transition from the blue to the red (and vice
versa) in the uppermost HRD. They are the intrinsically brightest "normal"
stars at visual light with absolute visual magnitudes up to -9. They are ideal
to study young stellar populations in galaxies beyond the Local Group to
determine chemical composition and evolution, interstellar extinction,
reddening laws and distances. We discuss most recent results on the
quantitative spectral analysis of such objects in galaxies beyond the Local
Group based on medium and low resolution spectra obtained with the ESO VLT and
Keck. We describe the analysis method including the determination of
metallicity and metallicity gradients. A new method to measure accurate
extragalactic distances based on the stellar gravities and effective
temperatures is presented, the flux weighted gravity - luminosity relationship
(FGLR). The FGLR is a purely spectroscopic method, which overcomes the
untertainties introduced by interstellar extinction and variations of
metallicity, which plague all photometric stellar distance determination
methods. We discuss the perspectives of future work using the giant
ground-based telescopes of the next generation such as the TMT, the GMT and the
E-ELT.


title: Improved Lower Bounds for Constant GC-Content DNA Codes

abstract:
  The design of large libraries of oligonucleotides having constant GC-content
and satisfying Hamming distance constraints between oligonucleotides and their
Watson-Crick complements is important in reducing hybridization errors in DNA
computing, DNA microarray technologies, and molecular bar coding. Various
techniques have been studied for the construction of such oligonucleotide
libraries, ranging from algorithmic constructions via stochastic local search
to theoretical constructions via coding theory. We introduce a new stochastic
local search method which yields improvements up to more than one third of the
benchmark lower bounds of Gaborit and King (2005) for n-mer oligonucleotide
libraries when n <= 14. We also found several optimal libraries by computing
maximum cliques on certain graphs.

categories: cs.IT cs.DS math.CO math.IT q-bio.GN q-bio.QM


title:
The Sizes of Optimal q-Ary Codes of Weight Three and Distance Four: A
  Complete Solution

abstract:
  This correspondence introduces two new constructive techniques to complete
the determination of the sizes of optimal q-ary codes of constant weight three
and distance four.


title:
Phenomenological dynamics of loop quantum cosmology in Kantowski-Sachs
  spacetime

abstract:
  The fundamental theory and the semiclassical description of loop quantum
cosmology (LQC) have been studied in the Friedmann-Robertson-Walker and Bianchi
I models. As an extension to include both anisotropy and intrinsic curvature,
this paper investigates the cosmological model of Kantowski-Sachs spacetime
with a free massless scalar field at the level of phenomenological dynamics
with the LQC discreteness corrections. The LQC corrections are implemented in
two different improved quantization schemes. In both schemes, the big bang and
big crunch singularities of the classical solution are resolved and replaced by
the big bounces when the area or volume scale factor approaches the critical
values in the Planck regime measured by the reference of the scalar field
momentum. Symmetries of scaling are also noted and suggest that the fundamental
spatial scale (area gap) may give rise to a temporal scale. The bouncing
scenarios are in an analogous fashion of the Bianchi I model, naturally
extending the observations obtained previously.


title:
The Equivalence between Uniqueness and Continuous Dependence of Solution
  for BSDEs with Continuous Coefficient

abstract:
  In this paper, we will prove that, if the coefficient $g=g(t,y,z)$ of a BSDE
is assumed to be continuous and linear growth in $(y,z)$, then the uniqueness
of solution and continuous dependence with respect to $g$ and the terminal
value $\xi$ are equivalent.


title:
Gravitational collapse of a spherical star with heat flow as a possible
  energy mechanism of gamma-ray bursts

abstract:
  We investigate the gravitational collapse of a spherically symmetric,
inhomogeneous star, which is described by a perfect fluid with heat flow and
satisfies the equation of state $p=\rho/3$ at its center. In the process of the
gravitational collapsing, the energy of the whole star is emitted into space.
And the remaining spacetime is a Minkowski one without a remnant at the end of
the process. For a star with a solar mass and solar radius, the total energy
emitted is at the order of $10^{54}$ {\rm erg}, and the time-scale of the
process is about $8s$. These are in the typical values for a gamma-ray burst.
Thus, we suggest the gravitational collapse of a spherical star with heat flow
as a possible energy mechanism of gamma-ray bursts.


title: Very Large Spectroscopic Surveys with the VLT

abstract:
  Recently, it has been recognised that very large spectroscopic surveys
(several million spectra) are required to advance our understanding of Dark
Energy (via baryonic wiggles) and the detailed history of our Local Group of
galaxies (via Galactic Archeology or near-field cosmology). In this paper I
make a preliminary exploration of how this might be done by putting a wide
field, optical, prime-focus fibre-fed spectroscopic facility on one of the
VLT's UTs.


title:
Unramified extensions and geometric $\mathbb{Z}_p$-extensions of global
  function fields

abstract:
  We study on finite unramified extensions of global function fields (function
fields of one valuable over a finite field). We show two results. One is an
extension of Perret's result about the ideal class group problem. Another is a
construction of a geometric $\mathbb{Z}_p$-extension which has a certain
property.


title: Numerical method for evolving the Projected Gross-Pitaevskii equation

abstract:
  In this paper we describe a method for evolving the projected
Gross-Pitaevskii equation (PGPE) for a Bose gas in a harmonic oscillator
potential. The central difficulty in solving this equation is the requirement
that the classical field is restricted to a small set of prescribed modes that
constitute the low energy classical region of the system. We present a scheme,
using a Hermite-polynomial based spectral representation, that precisely
implements this mode restriction and allows an efficient and accurate solution
of the PGPE. We show equilibrium and non-equilibrium results from the
application of the PGPE to an anisotropic trapped three-dimensional Bose gas.


title:
Integration with respect to fractional local times with Hurst index $H$
  greater than 1/2

abstract:
  Let ${\mathscr L}^H(x,t)=2H\int_0^t\delta(B^H_s-x)s^{2H-1}ds$ be the weighted
local time of fractional Brownian motion $B^H$ with Hurst index $1/2<H<1$. In
this paper, we use Young integration to study the integral of determinate
functions $\int_{\mathbb R}f(x){\mathscr L}^H(dx,t)$. As an application, we
investigate the {\it weighted quadratic covariation} $[f(B^H),B^H]^{(W)}$
defined by $$ [f(B^H),B^H]^{(W)}_t:=\lim_{n\to \infty}2H\sum_{k=0}^{n-1}
k^{2H-1}\{f(B^H_{t_{k+1}})-f(B^H_{t_{k}})\}(B^H_{t_{k+1}}-B^H_{t_{k}}), $$
where the limit is uniform in probability and $t_k=kt/n$. We show that it
exists and $$ [f(B^H),B^H]^{(W)}_t=-\int_{\mathbb R}f(x){\mathscr L}^H(dx,t),
$$ provided $f$ is of bounded $p$-variation with $1\leq p<\frac{2H}{1-H}$.
Moreover, we extend this result to the time-dependent case. These allow us to
write the fractional It\^{o} formula for new classes of functions.


title: Superconducting Polarons and Bipolarons

abstract:
  The BCS theory has been extended by us to the strong-coupling regime where
carriers are small lattice polarons and bipolarons. Here I review the
multi-polaron strong-coupling theory of superconductivity. Attractive electron
correlations, prerequisite to any superconductivity, are caused by an almost
unretarded electron-phonon interaction sufficient to overcome the direct
Coulomb repulsion in this regime. Low energy physics is that of small polarons
and bipolarons, which are itinerant quasiparticles existing in the Bloch states
at temperatures below the characteristic phonon frequency. I identify the
long-range Froehlich electron-phonon interaction with c-axis polarised optical
phonons as the most essential for pairing in superconducting cuprates. A number
of key observations have been predicted or explained with polarons and
bipolarons including unusual isotope effects and upper critical fields, normal
state (pseudo)gaps, kinetic properties and diamagnetism, and giant proximity
effects. These and some other observations provide strong evidence for a novel
state of electronic matter in layered cuprates, which is a charged Bose-liquid
of small mobile bipolarons.


title: A simply connected surface of general type with p_g=0 and K^2=4

abstract:
  As the sequel to [5, 7], we construct a simply connected minimal complex
surface of general type with p_g = 0 and K^2 = 4 by using a rational blow-down
surgery and Q-Gorenstein smoothing theory.


title: Categorification of integrable representations of quantum groups

abstract:
  We categorify the highest weight integrable representations and their tensor
products of a symmetric quantum Kac-Moody algebra. As byproducts, we obtain a
geometric realization of Lusztig's canonical bases of these representations as
well as a new positivity result. The main ingredient in the underlying
geometric construction is a class of micro-local perverse sheaves on quiver
varieties.


title:
Deforming motivic theories I: Pure weight perfect Modules on divisorial
  schemes

abstract:
  In this paper, we introduce a notion of weight r pseudo-coherent Modules
associated to a regular closed immersion i:Y -> X of codimension r, and prove
that there is a canonical derived Morita equivalence between the DG-category of
perfect complexes on a divisorial scheme X whose cohomological support are in Y
and the DG-category of bounded complexes of weight r pseudo-coherent
O_X-Modules supported on Y. The theorem implies that there is the canonical
isomorphism between the Bass-Thomason-Trobaugh non-connected K-theory [TT90],
[Sch06] (resp. the Keller-Weibel cyclic homology [Kel98], [Wei96]) for the
immersion and the Schlichting non-connected K-theory [Sch04] associated to
(resp. that of) the exact category of weight r pseudo-coherent Modules. For the
connected K-theory case, this result is just Exercise 5.7 in [TT90]. As its
application, we will decide on a generator of the topological filtration on the
non-connected K-theory (resp. cyclic homology theory) for affine Cohen-Macaulay
schemes.


title: On the cubicity of AT-free graphs and circular-arc graphs

abstract:
  A unit cube in $k$ dimensions ($k$-cube) is defined as the the Cartesian
product $R_1\times R_2\times...\times R_k$ where $R_i$(for $1\leq i\leq k$) is
a closed interval of the form $[a_i,a_i+1]$ on the real line. A graph $G$ on
$n$ nodes is said to be representable as the intersection of $k$-cubes (cube
representation in $k$ dimensions) if each vertex of $G$ can be mapped to a
$k$-cube such that two vertices are adjacent in $G$ if and only if their
corresponding $k$-cubes have a non-empty intersection. The \emph{cubicity} of
$G$ denoted as $\cubi(G)$ is the minimum $k$ for which $G$ can be represented
as the intersection of $k$-cubes.
  We give an $O(bw\cdot n)$ algorithm to compute the cube representation of a
general graph $G$ in $bw+1$ dimensions given a bandwidth ordering of the
vertices of $G$, where $bw$ is the \emph{bandwidth} of $G$. As a consequence,
we get $O(\Delta)$ upper bounds on the cubicity of many well-known graph
classes such as AT-free graphs, circular-arc graphs and co-comparability graphs
which have $O(\Delta)$ bandwidth. Thus we have: 1) $\cubi(G)\leq 3\Delta-1$, if
$G$ is an AT-free graph. 2) $\cubi(G)\leq 2\Delta+1$, if $G$ is a circular-arc
graph. 3) $\cubi(G)\leq 2\Delta$, if $G$ is a co-comparability graph. Also for
these graph classes, there are constant factor approximation algorithms for
bandwidth computation that generate orderings of vertices with $O(\Delta)$
width. We can thus generate the cube representation of such graphs in
$O(\Delta)$ dimensions in polynomial time.


title:
Condensation phenomena of conserved-mass aggregation model on weighted
  complex networks

abstract:
  We investigate the condensation phase transitions of conserved-mass
aggregation (CA) model on weighted scale-free networks (WSFNs). In WSFNs, the
weight $w_{ij}$ is assigned to the link between the nodes $i$ and $j$. We
consider the symmetric weight given as $w_{ij}=(k_i k_j)^\alpha$. In CA model,
the mass $m_i$ on the randomly chosen node $i$ diffuses to a linked neighbor of
$i$,$j$, with the rate $T_{ji}$ or an unit mass chips off from the node $i$ to
$j$ with the rate $\omega T_{ji}$. The hopping probability $T_{ji}$ is given as
$T_{ji}= w_{ji}/\sum_{<l>} w_{li}$, where the sum runs over the linked
neighbors of the node $i$. On the WSFNs, we numerically show that a certain
critical $\alpha_c$ exists below which CA model undergoes the same type of the
condensation transitions as those of CA model on regular lattices. However for
$\alpha \geq \alpha_c$, the condensation always occurs for any density $\rho$
and $\omega$. We analytically find $\alpha_c = (\gamma-3)/2$ on the WSFN with
the degree exponent $\gamma$. To obtain $\alpha_c$, we analytically derive the
scaling behavior of the stationary distribution $P^{\infty}_k$ of finding a
walker at nodes with degree $k$, and the probability $D(k)$ of finding two
walkers simultaneously at the same node with degree $k$. We find $P^{\infty}_k
\sim k^{\alpha+1-\gamma}$ and $D(k) \sim k^{2(\alpha+1)-\gamma}$ respectively.
With $P^{\infty}_k$, we also show analytically and numerically that the average
mass $m(k)$ on a node with degree $k$ scales as $k^{\alpha+1}$ without any
jumps at the maximal degree of the network for any $\rho$ as in the SFNs with
$\alpha=0$.


title:
Test of the heavy quark-light diquark approximation for baryons with a
  heavy quark

abstract:
  We check a commonly used approximation in which a baryon with a heavy quark
is described as a heavy quark-light diquark system. The heavy quark influences
the diquark internal motion reducing the average distance between the two light
quarks. Besides, we show how the average distance between the heavy quark and
any of the light quarks, and that between the heavy quark and the center of
mass of the light diquark, are smaller than the distance between the two light
quarks, which seems to contradict the heavy quark-light diquark picture. This
latter result is in agreement with expectations from QCD sum rules and lattice
QCD calculations. Our results also show that the diquark approximations
produces larger masses than the ones obtained in a full calculation.


title: Formation of antihydrogen in antiproton - positron collision

abstract:
  A quantum mechanical approach is proposed for the formation of antihydrogen
in the ground and excited states (2s, 2p) via the mechanism of three body
recombination (TBR) inside a trapped plasma of anti proton and positron or in
the collision between the two beams of them. Variations of the differential
(DCS) as well as the total (TCS) formation cross sections are studied as a
function of the incident energies of both the active and the spectator
positrons. Significantly large cross sections are found at very low incident
energies in the TBR process as compared to other processes leading to
antihydrogen. The present formation cross section decreases with increasing
positron energy (temperature) but no simple power law could be predicted for it
covering the entire energy range, corroborating the experimental findings
qualitatively. The formation cross sections are found to be much higher for
unequal energies of the two positrons than for equal energies, as expected
physically.


title:
Study of the Power Beam Pattern of RATAN-600 During the Deep RZF Survey
  (1998-2003)

abstract:
  This paper proposes a method for constructing an experimental power beam
pattern (PB) of RATAN-600 based on the sample of NVSS sources observed in the
process of a deep sky survey near local zenith. The data obtained from
observations of radio sources at wave 7.6 cm in nine bands of the survey (the
2002 and 2003 sets) are used to construct vertical PB of the telescope at
rather large offsets from the central horizontal section of the PB (+/-36').
The experimental PBs obtained using different methods are compared and the
root-mean-square deviations of the experimental PB from the corresponding
computed PB are determined. The stability of the power beam pattern in its
central part (+/-6') during the RATAN-600 Zenith Field (RZF) survey (1998-2003)
and the accuracies of the fluxes of the sources observed within the framework
of this survey and included into the RZF catalog are estimated.


title:
A new stochastic process to model Heart Rate series during exhaustive
  run and an estimator of its fractality parameter

abstract:
  In order to interpret and explain the physiological signal behaviors, it can
be interesting to find some constants among the fluctuations of these data
during all the effort or during different stages of the race (which can be
detected using a change points detection method). Several recent papers have
proposed the long-range dependence (Hurst) parameter as such a constant.
However, their results induce two main problems. Firstly, DFA method is usually
applied for estimating this parameter. Clearly, such a method does not provide
the most efficient estimator and moreover it is not at all robust even in the
case of smooth trends. Secondly, this method often gives estimated Hurst
parameters larger than 1, which is the larger possible value for long memory
stationary processes. In this article we propose solutions for both these
problems and we define a new model allowing such estimated parameters.


title:
Variable selection for the multicategory SVM via adaptive sup-norm
  regularization

abstract:
  The Support Vector Machine (SVM) is a popular classification paradigm in
machine learning and has achieved great success in real applications. However,
the standard SVM can not select variables automatically and therefore its
solution typically utilizes all the input variables without discrimination.
This makes it difficult to identify important predictor variables, which is
often one of the primary goals in data analysis. In this paper, we propose two
novel types of regularization in the context of the multicategory SVM (MSVM)
for simultaneous classification and variable selection. The MSVM generally
requires estimation of multiple discriminating functions and applies the argmax
rule for prediction. For each individual variable, we propose to characterize
its importance by the supnorm of its coefficient vector associated with
different functions, and then minimize the MSVM hinge loss function subject to
a penalty on the sum of supnorms. To further improve the supnorm penalty, we
propose the adaptive regularization, which allows different weights imposed on
different variables according to their relative importance. Both types of
regularization automate variable selection in the process of building
classifiers, and lead to sparse multi-classifiers with enhanced
interpretability and improved accuracy, especially for high dimensional low
sample size data. One big advantage of the supnorm penalty is its easy
implementation via standard linear programming. Several simulated examples and
one real gene data analysis demonstrate the outstanding performance of the
adaptive supnorm penalty in various data settings.


title: Linearity defects of modules over commutative rings

abstract:
  This article concerns linear parts of minimal resolutions of finitely
generated modules over commutative local, or graded rings. The focus is on the
linearity defect of a module, which marks the point after which the linear part
of its minimal resolution is acyclic. The results established track the change
in this invariant under some standard operations in commutative algebra. As one
of the applications, it is proved that a local ring is Koszul if and only if it
admits a Koszul module that is Cohen-Macaulay of minimal degree. An injective
analogue of the linearity defect is introduced and studied. The main results
express this new invariant in terms of linearity defects of free resolutions,
and relate it to other ring theoretic and homological invariants of the module.


title: Editorial: Statistics and "The lost tomb of Jesus"

abstract:
  What makes a problem suitable for statistical analysis? Are historical and
religious questions addressable using statistical calculations? Such issues
have long been debated in the statistical community and statisticians and
others have used historical information and texts to analyze such questions as
the economics of slavery, the authorship of the Federalist Papers and the
question of the existence of God. But what about historical and religious
attributions associated with information gathered from archeological finds? In
1980, a construction crew working in the Jerusalem neighborhood of East Talpiot
stumbled upon a crypt. Archaeologists from the Israel Antiquities Authority
came to the scene and found 10 limestone burial boxes, known as ossuaries, in
the crypt. Six of these had inscriptions. The remains found in the ossuaries
were reburied, as required by Jewish religious tradition, and the ossuaries
were catalogued and stored in a warehouse. The inscriptions on the ossuaries
were catalogued and published by Rahmani (1994) and by Kloner (1996) but there
reports did not receive widespread public attention. Fast forward to March
2007, when a television ``docudrama'' aired on The Discovery Channel entitled
``The Lost Tomb of Jesus'' touched off a public and religious controversy--one
only need think about the title to see why there might be a controversy! The
program, and a simultaneously published book [Jacobovici and Pellegrino
(2007)], described the ``rediscovery'' of the East Talpiot archeological find
and they presented interpretations of the ossuary inscriptions from a number of
perspectives. Among these was a statistical calculation attributed to the
statistician Andrey Feuerverger: ``that the odds that all six names would
appear together in one tomb are 1 in 600, calculated conservatively--or
possibly even as much as one in one million.''


title: The generality of the zero-one laws

abstract:
  We prove game-theoretic generalizations of some well known zero-one laws. Our
proofs make the martingales behind the laws explicit, and our results
illustrate how martingale arguments can have implications going beyond
measure-theoretic probability.


title: (De)quantization of black hole charges

abstract:
  We argue that magnetic and electric charges of the Reissner-Nordstrom black
hole are quantized in CP conserving theories. Dequantization phenomenon occurs
when CP is broken either explicitly or effectively, and, as a result, pure
magnetic black holes are not possible. Two examples illustrating this
phenomenon are discussed. One is the electric charge induced by the neutral
pion field in a magnetically charged black hole, and another is the electric
charge induced due to the massive spin-two field emerging from possible higher
curvature terms.


title: Simulation of a Zenith-Field Sky Survey on RATAN-600

abstract:
  In this paper we simulate a deep multi-frequency zenith-field sky survey on
RATAN-600 (the RZF survey). In our simulations we use the 1.4 GHz sky images
obtained in the NVSS survey. We convolved NVSS images with the two-dimensional
power beam pattern of RATAN-600 and obtain simulated 24-hour scans of sky
transits at all wavelengths of the RZF survey. For the 7.6 cm wavelength we
analyze the effect of the image area size on the results of the simulation. We
estimate the accuracy of the determination of source fluxes on simulated scans
and derive the distributions of the spectral indices of the sources. We use the
simulated scans to clean real records of the RZF survey at 7.6 cm. The standard
error of the residual noise at this wavelength is about 1 mJy.


title: Decoherence and asymptotic entanglement in open quantum dynamics

abstract:
  In the framework of the theory of open systems based on completely positive
quantum dynamical semigroups, we determine the degree of quantum decoherence of
a harmonic oscillator interacting with a thermal bath. It is found that the
system manifests a quantum decoherence which is more and more significant in
time. We also calculate the decoherence time and show that it has the same
scale as the time after which thermal fluctuations become comparable with
quantum fluctuations. Then we solve the master equation for two independent
harmonic oscillators interacting with an environment in the asymptotic
long-time regime. We give a description of the continuous-variable asymptotic
entanglement in terms of the covariance matrix of the quantum states of the
considered system for an arbitrary Gaussian input state. Using the Peres-Simon
necessary and sufficient condition for separability of two-mode Gaussian
states, we show that the two non-interacting systems immersed in a common
environment become asymptotically entangled for certain environments, so that
in the long-time regime they manifest non-local quantum correlations.


title: Asymptotic stability of solitons for the Benjamin-Ono equation

abstract:
  In this paper, we prove the asymptotic stability of the family of solitons of
the Benjamin-Ono equation in the energy space. The proof is based on a
Liouville property for solutions close to the solitons for this equation, in
the spirit of Martel and Merle (arXiv:0706.1174v2). As a corollary of the
proofs, we obtain the asymptotic stability of exact multi-solitons.


title:
A momentum-space representation of Green's functions with modified
  dispersion relations on general backgrounds

abstract:
  We consider the problem of calculating the Green's functions associated to a
massive scalar field with modified dispersion relations. We analyze the case
when dispersion is modified by higher derivative spatial operators acting on
the field orthogonally to a preferred direction, determined by a unit time-like
vector field. By assuming that the integral curves of the vector field are
geodesics, we expand the modified Klein-Gordon equation in Fermi normal
coordinates. By means of a Fourier transform, we find a series representation
in momentum-space of the Green's functions. The coefficients of the series are
geometrical terms containing combinations of the Ricci tensor and the vector
field, as expected from previous calculations with different methods and for
specific backgrounds.


title: The Place of Recurrent Novae among the Symbiotic Stars

abstract:
  The observational properties of recurrent novae indicate that they can be
divided into two subclasses:systems with a dwarf and a red giant secondary,
respectively. The second type -- which includes RS Oph -- bears many
similarities to symbiotic stars.


title:
Unusual spin-wave population in nickel after femtosecond laser pulse
  excitation

abstract:
  The spin-wave relaxation mechanisms after intense laser excitation in
ferromagnetic nickel films are investigated with all-optical pump-probe
experiments. Uniform precession (Kittel mode), Damon-Eshbach surface modes and
perpendicular standing spin waves can be identified by their dispersion f(H).
However, different to other ferromagnets f(H) deviates from the expected
behavior. Namely, a mode discontinuity is observed, that can be attributed to a
non-linear process. Above a critical field the power spectrum reveals a
redistribution of the energy within the spin-wave spectrum populated.


title: Generating series of classes of Hilbert schemes of points on orbifolds

abstract:
  In this short note we use the notion of power structure over the Grothendieck
ring of complex algebraic varieties to study generating series of classes of
Hilbert schemes of points on complex orbifolds.


title: Symmetry and Integrability of Classical Field Equations

abstract:
  A number of characteristics of integrable nonlinear partial differential
equations (PDE's) for classical fields are reviewed, such as Backlund
transformations, Lax pairs, and infinite sequences of conservation laws. An
algebraic approach to the symmetry problem of PDE's is described, suitable for
PDE's the solutions of which are non-scalar fields (e.g., are in the form of
matrices). A method is proposed which, in certain cases, may "unify" the
symmetry and integrability properties of a nonlinear PDE. Application is made
to the self-dual Yang-Mills equation and the Ernst equation of General
Relativity.


title: Cohomology of twisted tensor products

abstract:
  It is well known that the cohomology of a tensor product is essentially the
tensor product of the cohomologies. We look at twisted tensor products, and
investigate to which extend this is still true. We give an explicit description
of the $\Ext$-algebra of the tensor product of two modules, and under certain
additional conditions, describe an essential part of the Hochschild cohomology
ring of a twisted tensor product. As an application, we characterize precisely
when the cohomology groups over a quantum complete intersection are finitely
generated over the Hochschild cohomology ring. Moreover, both for quantum
complete intersections and in related cases we obtain a lower bound for the
representation dimension of the algebra.


title:
The effects of ram-pressure stripping on the internal kinematics of
  simulated spiral galaxies

abstract:
  We investigate the influence of ram-pressure stripping on the internal gas
kinematics of simulated spiral galaxies. Additional emphasis is put on the
question of how the resulting distortions of the gaseous disc are visible in
the rotation curve and/or the full 2D velocity field of galaxies at different
redshifts. A Milky-Way type disc galaxy is modelled in combined
N-body/hydrodynamic simulations with prescriptions for cooling, star formation,
stellar feedback, and galactic winds. This model galaxy moves through a
constant density and temperature gas, which has parameters similar to the
intra-cluster medium (ICM). Rotation curves (RCs) and 2D velocity fields of the
gas are extracted from these simulations in a way that follows the procedure
applied to observations of distant, small, and faint galaxies as closely as
possible. We find that the appearance of distortions of the gaseous disc due to
ram-pressure stripping depends on the direction of the acting ram pressure. In
the case of face-on ram pressure, the distortions mainly appear in the outer
parts of the galaxy in a very symmetric way. In contrast, in the case of
edge-on ram pressure we find stronger distortions. The 2D velocity field also
shows signatures of the interaction in the inner part of the disc. At angles
smaller than 45 degrees between the ICM wind direction and the disc, the
velocity field asymmetry increases significantly compared to larger angles.
Compared to distortions caused by tidal interactions, the effects of
ram-pressure stripping on the velocity field are relatively low in all cases
and difficult to observe at intermediate redshift in seeing-limited
observations. (abridged)


title:
Transition from fractal to non-fractal scalings in growing scale-free
  networks

abstract:
  Real networks can be classified into two categories: fractal networks and
non-fractal networks. Here we introduce a unifying model for the two types of
networks. Our model network is governed by a parameter $q$. We obtain the
topological properties of the network including the degree distribution,
average path length, diameter, fractal dimensions, and betweenness centrality
distribution, which are controlled by parameter $q$. Interestingly, we show
that by adjusting $q$, the networks undergo a transition from fractal to
non-fractal scalings, and exhibit a crossover from `large' to small worlds at
the same time. Our research may shed some light on understanding the evolution
and relationships of fractal and non-fractal networks.


title: Principal 2-bundles and their gauge 2-groups

abstract:
  In this paper we introduce principal 2-bundles and show how they are
classified by non-abelian Cech cohomology. Moreover, we show that their gauge
2-groups can be described by 2-group-valued functors, much like in classical
bundle theory. Using this, we show that, under some mild requirements, these
gauge 2-groups possess a natural smooth structure. In the last section we
provide some explicit examples.


title: Succinct Data Structures for Retrieval and Approximate Membership

abstract:
  The retrieval problem is the problem of associating data with keys in a set.
Formally, the data structure must store a function f: U ->{0,1}^r that has
specified values on the elements of a given set S, a subset of U, |S|=n, but
may have any value on elements outside S. Minimal perfect hashing makes it
possible to avoid storing the set S, but this induces a space overhead of
Theta(n) bits in addition to the nr bits needed for function values. In this
paper we show how to eliminate this overhead. Moreover, we show that for any k
query time O(k) can be achieved using space that is within a factor 1+e^{-k} of
optimal, asymptotically for large n. If we allow logarithmic evaluation time,
the additive overhead can be reduced to O(log log n) bits whp. The time to
construct the data structure is O(n), expected. A main technical ingredient is
to utilize existing tight bounds on the probability of almost square random
matrices with rows of low weight to have full row rank. In addition to direct
constructions, we point out a close connection between retrieval structures and
hash tables where keys are stored in an array and some kind of probing scheme
is used. Further, we propose a general reduction that transfers the results on
retrieval into analogous results on approximate membership, a problem
traditionally addressed using Bloom filters. Again, we show how to eliminate
the space overhead present in previously known methods, and get arbitrarily
close to the lower bound. The evaluation procedures of our data structures are
extremely simple (similar to a Bloom filter). For the results stated above we
assume free access to fully random hash functions. However, we show how to
justify this assumption using extra space o(n) to simulate full randomness on a
RAM.


title:
Does Spin-Orbit Coupling Effect Favor Planar Structures for Small
  Platinum Clusters?

abstract:
  We have performed full-relativistic density functional theory calculations to
study the geometry and binding energy of different isomers of free platinum
clusters Pt$_{n}$ ($n=4-6$) within the spin multiplicities from singlet to
nonet. The spin-orbit coupling effect has been discussed for the minimum-energy
structures, relative stabilities, vibrational frequencies, magnetic moments,
and the highest occupied and lowest unoccupied molecular-orbital gaps. It is
found in contrast to some of the previous calculations that 3-dimentional
configurations are still lowest energy structures of these clusters, although
spin-orbit effect makes some planar or quasi-planar geometries more stable than
some other 3-dimentional isomers.


title: Simple proofs for universal binary Hermitian lattices

abstract:
  If a positive definite Hermitian lattice represents all positive integers, we
call it universal. Several mathematicians, including the author, found 25
universal binary Hermitian lattices. But their ad hoc proofs are complicated.
We give simple and unified proofs.


abstract:
  Realistic calculations of nuclear disappearance lifetimes induced by
neutron-antineutron oscillations are reported for oxygen and iron, using
antineutron nuclear potentials derived from a recent comprehensive analysis of
antiproton atomic X-ray and radiochemical data. A lower limit of 3.3 x 10E8 s
on the neutron-antineutron oscillation time is derived from the
Super-Kamiokande I new lower limit of 1.77 x 10E32 yr on the neutron lifetime
in oxygen. Antineutron scattering lengths in carbon and nickel, needed in trap
experiments using ultracold neutrons, are calculated from updated antinucleon
optical potentials at threshold, with results shown to be largely model
independent.


title:
In-season prediction of batting averages: A field test of empirical
  Bayes and Bayes methodologies

abstract:
  Batting average is one of the principle performance measures for an
individual baseball player. It is natural to statistically model this as a
binomial-variable proportion, with a given (observed) number of qualifying
attempts (called ``at-bats''), an observed number of successes (``hits'')
distributed according to the binomial distribution, and with a true (but
unknown) value of $p_i$ that represents the player's latent ability. This is a
common data structure in many statistical applications; and so the
methodological study here has implications for such a range of applications. We
look at batting records for each Major League player over the course of a
single season (2005). The primary focus is on using only the batting records
from an earlier part of the season (e.g., the first 3 months) in order to
estimate the batter's latent ability, $p_i$, and consequently, also to predict
their batting-average performance for the remainder of the season. Since we are
using a season that has already concluded, we can then validate our estimation
performance by comparing the estimated values to the actual values for the
remainder of the season. The prediction methods to be investigated are
motivated from empirical Bayes and hierarchical Bayes interpretations. A newly
proposed nonparametric empirical Bayes procedure performs particularly well in
the basic analysis of the full data set, though less well with analyses
involving more homogeneous subsets of the data. In those more homogeneous
situations better performance is obtained from appropriate versions of more
familiar methods. In all situations the poorest performing choice is the
na\"{{\i}}ve predictor which directly uses the current average to predict the
future average.


title: Configurations and Observables in an Ising Model with Heat Flow

abstract:
  We study a two dimensional Ising model between thermostats at different
temperatures. By applying the recently introduced KQ dynamics, we show that the
system reaches a steady state with coexisting phases transversal to the heat
flow. The relevance of such complex states on thermodynamic or geometrical
observables is investigated. In particular, we study energy, magnetization and
metric properties of interfaces and clusters which, in principle, are sensitive
to local features of configurations. With respect to equilibrium states, the
presence of the heat flow amplifies the fluctuations of both thermodynamic and
geometrical observables in a domain around the critical energy. The dependence
of this phenomenon on various parameters (size, thermal gradient, interaction)
is discussed also with reference to other possible diffusive models.


title: On the QKD relaying models

abstract:
  We investigate Quantum Key Distribution (QKD) relaying models. Firstly, we
propose a novel quasi-trusted QKD relaying model. The quasi-trusted relays are
defined as follows: (i) being honest enough to correctly follow a given
multi-party finite-time communication protocol; (ii) however, being under the
monitoring of eavesdroppers. We develop a simple 3-party quasi-trusted model,
called Quantum Quasi-Trusted Bridge (QQTB) model, to show that we could
securely extend up to two times the limited range of single-photon based QKD
schemes. We also develop the Quantum Quasi-Trusted Relay (QQTR) model to show
that we could securely distribute QKD keys over arbitrarily long distances. The
QQTR model requires EPR pair sources, but does not use entanglement swapping
and entanglement purification schemes. Secondly, we show that our quasi-trusted
models could be improved to become untrusted models in which the security is
not compromised even though attackers have full controls over some relaying
nodes. We call our two improved models the Quantum Untrusted Bridge (QUB) and
Quantum Untrusted Relay (QUR) ones. The QUB model works on single photons and
allows securely extend up to two times the limited QKD range. The QUR model
works on entangled photons but does not use entanglement swapping and
entanglement purification operations. This model allows securely transmit
shared keys over arbitrarily long distances without dramatically decreasing the
key rate of the original QKD schemes.


title: Indistinguishable photons from a diode

abstract:
  We generate indistinguishable photons from a semiconductor diode containing a
InAs/GaAs quantum dot. Using an all-electrical technique to populate and
control a single-photon emitting state we filter-out dephasing by
Stark-shifting the emission energy on timescales below the dephasing time of
the state. Mixing consecutive photons on a beam-splitter we observe two-photon
interference with a visibility of 64%.


title:
A beyond mean field analysis of the shape transition in the Neodymium
  isotopes

abstract:
  The beyond mean field approximation combined with the Gogny interaction is
used to analyze the spherical to prolate deformed shape transition in the
Neodymium isotopic chain. The vibrator as well as the rotor limits are nicely
reproduced while the transitional region is only qualitatively described
probably due to the lack of triaxial correlations in the calculations. Our
results do not support the interpretation of $^{150}$Nd as a critical point
nucleus and question the interpretation of shape changes as nuclear shape phase
transitions.


title: Models of Z/p^2 Z over a d.v.r. of unequal characteristic

abstract:
  Let R be a discrete valuation ring of unequal characteristic which contains a
primitive p^2-th root of unity. If K is the fraction field of R, it is well
known that (Z/p^2 Z)_K is isomorphic to \mu_{p^2,K}. We prove that any finite
and flat R-group scheme of order p^2 isomorphic to (Z/p^2 Z)_K on the generic
fiber (i.e. a model of (Z/p^2 Z)_K), is the kernel in a short exact sequence
which generically coincides with the Kummer sequence. We will explicitly
describe and classify such models.


title:
Pull over strategy for the evacuation of an emergency vehicle in
  highways

abstract:
  By using a simplified two-lane cellular automata model for traffic flow, we
simulate an evacuation of an emergency vehicle (EV) in highways. We introduce
the pull over strategy to facilitate the evacuation of the EV in highways. We
demonstrate numerically that this pulling over of cars promotes a faster moving
of the EV in traffic flow and minimize the EV's impact on the overall traffic.


title: A spatially explicit model for tropical tree diversity patterns

abstract:
  A complex two-parameter model resembling the classical voter model is
introduced to describe macroecological properties of tropical tree communities.
Monte-Carlo type computer simulations are performed on the model, investigating
species abundances and the spatial distribution of individuals and species.
Simulation results are critically compared with the experimental data obtained
from a tree census on a 50 hectares area of the Barro Colorado Island (BCI),
Panama. The model parameters are optimized for reproducing quantitatively the
experimental results from the BCI dataset.


title:
Spin-polarized Quantum Transport in Mesoscopic Conductors: Computational
  Concepts and Physical Phenomena

abstract:
  Mesoscopic conductors are electronic systems of sizes in between nano- and
micrometers, and often of reduced dimensionality. In the phase-coherent regime
at low temperatures, the conductance of these devices is governed by quantum
interference effects, such as the Aharonov-Bohm effect and conductance
fluctuations as prominent examples. While first measurements of quantum charge
transport date back to the 1980s, spin phenomena in mesoscopic transport have
moved only recently into the focus of attention, as one branch of the field of
spintronics. The interplay between quantum coherence with confinement-,
disorder- or interaction-effects gives rise to a variety of unexpected spin
phenomena in mesoscopic conductors and allows moreover to control and engineer
the spin of the charge carriers: spin interference is often the basis for
spin-valves, -filters, -switches or -pumps. Their underlying mechanisms may
gain relevance on the way to possible future semiconductor-based spin devices.
  A quantitative theoretical understanding of spin-dependent mesoscopic
transport calls for developing efficient and flexible numerical algorithms,
including matrix-reordering techniques within Green function approaches, which
we will explain, review and employ.


title: On bijections between 231-avoiding permutations and Dyck paths

abstract:
  We construct a bijection between 231-avoiding permutations and Dyck paths
that sends the sum of the major index and the inverse major index of a
231-avoiding permutation to the major index of the corresponding Dyck path.
Furthermore, we relate this bijection to others and exhibit a bistatistic on
231-avoiding permutations which is related to the q,t-Catalan numbers.


title: Parton content of the real photon: astrophysical implications

abstract:
  We possess convincing experimental evidence for the fact that the real photon
has non-trivial parton structure. On the other hand, interactions of the cosmic
microwave background photons with high energy particles propagating through the
Universe play an important role in astrophysics. In this context, to invoke the
parton content could be convenient for calculations of the probabilities of
different processes involving these photons. As an example, the cross section
of inclusive resonant $W^+$ boson production in the reaction $\nu \gamma\to
W^+X$ is calculated by using the parton language. Neutrino--photon deep
inelastic scattering is considered.


title: An equivariant version of the monodromy zeta function

abstract:
  We offer an equivariant version of the classical monodromy zeta function of a
singularity as a series with coefficients from the Grothendieck ring of finite
G-sets tensored by the field of rational numbers. Main two ingredients of the
definition are equivariant Lefschetz numbers and the lambda-structure on the
Grothendieck ring of finite G-sets. We give an A'Campo type formula for the
equivariant zeta function.


title:
Nonadiabatic coherent evolution of two-level systems under spontaneous
  decay

abstract:
  In this paper we extend current perspectives in engineering reservoirs by
producing a time-dependent master equation leading to a nonstationary
superposition equilibrium state that can be nonadiabatically controlled by the
system-reservoir parameters. Working with an ion trapped inside a nonindeal
cavity we first engineer effective Hamiltonians that couple the electronic
states of the ion with the cavity mode. Subsequently, two classes of
decoherence-free evolution of the superposition of the ground and decaying
excited levels are achieved: those with time-dependent azimuthal or polar
angle. As an application, we generalise the purpose of an earlier study [Phys.
Rev. Lett. 96, 150403 (2006)], showing how to observe the geometric phases
acquired by the protected nonstationary states even under a nonadiabatic
evolution.


title: The General Solution of Bianchi Type $VII_h$ Vacuum Cosmology

abstract:
  The theory of symmetries of systems of coupled, ordinary differential
equations (ODE) is used to develop a concise algorithm in order to obtain the
entire space of solutions to vacuum Bianchi Einstein Field Equations (EFEs).
The symmetries used are the well known automorphisms of the Lie algebra for the
corresponding isometry group of each Bianchi Type, as well as the scaling and
the time re-parametrization symmetry. The application of the method to Type
VII_h results in (a) obtaining the general solution of Type VII_0 with the aid
of the third Painlev\'{e} transcendental (b) obtaining the general solution of
Type $VII_h$ with the aid of the sixth Painlev\'{e} transcendental (c) the
recovery of all known solutions (six in total) without a prior assumption of
any extra symmetry (d) The discovery of a new solution (the line element given
in closed form) with a G_3 isometry group acting on T_3, i.e. on time-like
hyper-surfaces, along with the emergence of the line element describing the
flat vacuum Type VII_0 Bianchi Cosmology.


title: Radial Balanced metrics on the unit disk

abstract:
  Let $\Phi$ be a strictly plurisubharmonic and radial function on the unit
disk ${\cal D}\subset {\complex}$ and let $g$ be the \K metric associated to
the \K form $\omega =\frac{i}{2}\partial\bar\partial\Phi$. We prove that if $g$
is $g_{eucl}$-balanced of height 3 (where $g_{eucl}$ is the standard Euclidean
metric on ${\complex}={\real}^2$), and the function $h(x)=e^{-\Phi (z)}$,
$x=|z|^2$, extends to an entire analytic function on ${\real}$, then $g$ equals
the hyperbolic metric. The proof of our result is based on a interesting
characterization of the function $f(x)=1-x$.


title:
Numerical Algorithms and Simulations for Reflected Backward Stochastic
  Differential Equations with two Continuous Barriers

abstract:
  In this paper we study different algorithms for reflected backward stochastic
differential equations (BSDE in short) with two continuous barriers basing on
random work framework. We introduce different numerical algorithms by
penalization method and reflected method. At last simulation results are also
presented.


title:
A new principle for choosing regularization parameter in certain inverse
  problems

abstract:
  A new parameter choice rule for inverse problems is introduced. This
parameter choice rule was developed for total variation regularization in
electron tomography and might in general be useful for $L^1$ regularization of
inverse problems with high levels of noise in the data.


title: The optomechanical instability in the quantum regime

abstract:
  We consider a generic optomechanical system, consisting of a driven optical
cavity and a movable mirror attached to a cantilever. Systems of this kind (and
analogues) have been realized in many recent experiments. It is well known that
those systems can exhibit an instability towards a regime where the cantilever
settles into self-sustained oscillations. In this paper, we briefly review the
classical theory of the optomechanical instability, and then discuss the
features arising in the quantum regime. We solve numerically a full quantum
master equation for the coupled system, and use it to analyze the photon
number, the cantilever's mechanical energy, the phonon probability distribution
and the mechanical Wigner density, as a function of experimentally accessible
control parameters. We observe and discuss the quantum-to-classical transition
as a function of a suitable dimensionless quantum parameter.


title: Fractional decay of quantum dots in real photonic crystals

abstract:
  We show that fractional decay may be observable in experiments using quantum
dots and photonic crystals with parameters that are currently achievable. We
focus on the case of inverse opal photonic crystals and locate the position in
the crystal where the effect is most pronounced. Furthermore, we quantify the
influence of absorptive loss and show that it is a limiting but not prohibitive
effect.


title: On distributional properties of perpetuities

abstract:
  We study probability distributions of convergent random series of a special
structure, called perpetuities. By giving a new argument, we prove that such
distributions are of pure type: degenerate, absolutely continuous, or
continuously singular. We further provide necessary and sufficient criteria for
the finiteness of $p$-moments, $p>0$ as well as exponential moments. In
particular, a formula for the abscissa of convergence of the moment generating
function is provided. The results are illustrated with a number of examples at
the end of the article.


title: Mean-field vs. stochastic models for transcriptional regulation

abstract:
  We introduce a minimal model description for the dynamics of transcriptional
regulatory networks. It is studied within a mean-field approximation, i.e., by
deterministic ode's representing the reaction kinetics, and by stochastic
simulations employing the Gillespie algorithm. We elucidate the different
results both approaches can deliver, depending on the network under study, and
in particular depending on the level of detail retained in the respective
description. Two examples are addressed in detail: the repressilator, a
transcriptional clock based on a three-gene network realized experimentally in
E. coli, and a bistable two-gene circuit under external driving, a
transcriptional network motif recently proposed to play a role in cellular
development.


title:
Universal Dynamic Conductivity and Quantized Visible Opacity of
  Suspended Graphene

abstract:
  We show that the optical transparency of suspended graphene is defined by the
fine structure constant, alpha, the parameter that describes coupling between
light and relativistic electrons and is traditionally associated with quantum
electrodynamics rather than condensed matter physics. Despite being only one
atom thick, graphene is found to absorb a significant (pi times alpha=2.3%)
fraction of incident white light, which is a consequence of graphene's unique
electronic structure. This value translates into universal dynamic conductivity
G =e^2/4h_bar within a few percent accuracy.


title:
Remarks on the accuracy of algorithms for motion by mean curvature in
  bounded domains

abstract:
  Simulations of motion by mean curvature in bounded domains, with applications
to bubble motion and grain growth, rely upon boundary conditions that are only
approximately compatible with the equation of motion. Three closed form
solutions for the problem exist, governing translation, rotation and expansion
of a single interface [1], providing the only benchmarks for algorithm
verification. We derive new identities for the translation solution. Then we
estimate the accuracy of a straightforward algorithm to recover the analytical
solution for different values of the velocity V given along the boundary. As
expected, for large V the error can reach unacceptable levels especially near
the boundary. We discuss factors influencing the accuracy and propose a simple
modification of the algorithm which improves the computational accuracy.


title:
Quantum Magnets under Pressure: Controlling Elementary Excitations in
  TlCuCl3

abstract:
  We follow the evolution of the elementary excitations of the quantum
antiferromagnet TlCuCl3 through the pressure-induced quantum critical point,
which separates a dimer-based quantum disordered phase from a phase of
long-ranged magnetic order. We demonstrate by neutron spectroscopy the
continuous emergence in the weakly ordered state of a low-lying but massive
excitation corresponding to longitudinal fluctuations of the magnetic moment.
This mode is not present in a classical description of ordered magnets, but is
a direct consequence of the quantum critical point.


title: Almost-periodic time observables for bound quantum systems

abstract:
  It is shown that a canonical time observable may be defined for any quantum
system having a discrete set of energy eigenvalues, thus significantly
generalising the known case of time observables for periodic quantum systems
(such as the harmonic oscillator). The general case requires the introduction
of almost-periodic probability operator measures (POMs), which allow the
expectation value of any almost-periodic function to be calculated. An entropic
uncertainty relation for energy and time is obtained which generalises the
known uncertainty relation for periodic quantum systems. While non-periodic
quantum systems with discrete energy spectra, such as hydrogen atoms, typically
make poor clocks that yield no more than 1 bit of time information, the
anisotropic oscillator provides an interesting exception. More generally, a
canonically conjugate observable may be defined for any Hermitian operator
having a discrete spectrum.


title:
Optical and Infrared Observations of the X-ray source 1WGA
  J1713.4$-$3949 in the G347.3-0.5 SNR

abstract:
  X-ray observations unveiled the existence of enigmatic point-like sources at
the centre of young supernova remnants (SNRs). These sources, dubbed Central
Compact Objects (CCOs), are thought to be neutron stars formed by the supernova
explosion. However, their multi-wavelength phenomenology is surprisingly
different from that of most young neutron stars.The aim of this work is to
understand the nature of the CCO 1WGA J1713.4-3949 in the G347.3-0.5 SNR,
through deep optical and IR observations, the first ever performed for this
source.By exploiting its derived Chandra X-ray position we carried out optical
(BVI) observations with the NTT and Adaptive Optics IR (JHKs) observations with
the VLT. We detected two faint (I~23.5, I~24.3.) patchy objects in the NTT
images, close to the Chandra error circle. They were clearly resolved in our
VLT images which unveiled a total of six candidate counterparts (17.8<H<20.3)
with quite red colours (H-Ks~0.6). If they are stars, none of them can be
associated with 1WGA J1713.4-3949 for the most likely values of distance and
hydrogen column density. The identification of the faintest candidate with the
neutron star itself can not be firmly excluded, while the identification with a
fallback disk is ruled out by its non-detection in the I band. No other
candidates are detected down to B~26, V~26.2, I~24.7, H~21.3 and K~20.5. Our
high-resolution IR imaging of unveiled a few objects close/within the Chandra
X-ray position of 1WGA J1713.4-3949. However, at present none of them can be
firmly identified as its likely counterpart.


title:
Dirac-harmonic maps from degenerating spin surfaces I: the Neveu-Schwarz
  case

abstract:
  We study Dirac-harmonic maps from degenerating spin surfaces with uniformly
bounded energy and show the so-called generalized energy identity in the case
that the domain converges to a spin surface with only Neveu-Schwarz type nodes.
We find condition that is both necessary and sufficient for the $W^{1,2} \times
L^{4}$ modulo bubbles compactness of a sequence of such maps.


title:
Eikonal contributions to ultra high energy neutrino-nucleon cross
  sections in low scale gravity models

abstract:
  We calculate low scale gravity effects on the cross section for
neutrino-nucleon scattering at center of mass energies up to the
Greisen-Zatsepin-Kuzmin (GZK) scale, in the eikonal approximation. We compare
the cases of an infinitely thin brane embedded in n=5 compactified
extra-dimensions, and of a brane with a physical tension M_{S}=1 TeV and
M_{S}=10 TeV. The extra dimensional Planck scale M_{D} is set at 10^{3} GeV and
2\times10^{3} GeV. We also compare our calculations with neutral current
standard model calculations in the same energy range, and compare the thin
brane eikonal cross section to its saddle point approximation. New physics
effects enhance the cross section by orders of magnitude on average. They are
quite sensitive to M_{S} and M_{D} choices, though much less sensitive to n.


title: Axionic Mirage Mediation

abstract:
  Although the mirage mediation is one of the most plausible mediation
mechanisms of supersymmetry breaking, it suffers from two crucial problems. One
is the \mu-/B \mu-problem and the second is the cosmological one. The former
stems from the fact that the B parameter tends to be comparable with the
gravitino mass, which is two order of magnitude larger than the other soft
masses. The latter problem is caused by the decay of the modulus whose
branching ratio into the gravitino pair is sizable. In this paper, we propose a
model of mirage mediation, in which Peccei-Quinn symmetry is incorporated. In
this axionic mirage mediation, it is shown that the PQ symmetry breaking scale
is dynamically determined around 10^{10-12} GeV due to the supersymmetry
breaking effects, and the \mu-problem can be solved naturally. Furthermore, in
our model, the lightest supersymmetric particle (LSP) is the axino, that is the
superpartner of the axion. The overabundance of the LSPs due to decays of
modulus/gravitino, which is the most serious cosmological difficulty in the
mirage mediation, can be avoided if the axino is sufficiently light. The
next-LSPs (NLSPs) produced by the gravitino decay eventually decay into the
axino LSPs, yielding the dominant component of the axinos remaining today. It
is shown that the axino with the mass of O(100) MeV is naturally realized,
which can constitute the dark matter of the Universe, with the free-streaming
length of the order of 0.1 Mpc. The saxion, the real scalar component of the
axion supermultiplet, can also be cosmologically harmless due to the dilution
of the modulus decay. The lifetime of NLSP is relatively long, but much shorter
than 1 sec., when the big-bang nucleosynthesis commences. The decay of NLSP
would provide intriguing collider signatures.


title: Dynamic Physical Systems: Energy Balances and Stability Issues

abstract:
  This paper discusses some links properties of operators with the well- known
physical concepts of hyperstability, passivity, energy dissipativeness and
conservativeness with positive realness properties of the transfer functions in
linear dynamic systems.


title: What is the state of the Early Universe?

abstract:
  As we follow our Universe to early times, we find that matter was crushed to
high densities, somewhat similar to the behavior at a black hole singularity.
String theory has made progress in explaining the internal structure of black
holes, so we would like to extrapolate the ideas learnt from black holes to the
early Universe. If we assume that we want the most probable state of the
Universe at early times, then we should look at the kind of state that
describes a generic black hole. This suggests a definite equation of state for
the matter in the early Universe. Quantum effects can stretch across
macroscopic distances in black holes, and these might be important in
understanding the early Universe as well.


title:
Resolving Stellar Populations outside the Local Group: MAD observations
  of UKS2323-326

abstract:
  We present a study aimed at deriving constraints on star formation at
intermediate ages from the evolved stellar populations in the dwarf irregular
galaxy UKS2323-326. These observations were also intended to demonstrate the
scientific capabilities of the multi-conjugated adaptive optics demonstrator
(MAD) implemented at the ESO Very Large Telescope as a test-bench of adaptive
optics (AO) techniques. We perform accurate, deep photometry of the field using
J and Ks band AO images of the central region of the galaxy. The near-infrared
(IR) colour-magnitude diagrams clearly show the sequences of asymptotic giant
branch (AGB) stars, red supergiants, and red giant branch (RGB) stars down to
~1 mag below the RGB tip. Optical-near-IR diagrams, obtained by combining our
data with Hubble Space Telescope observations, provide the best separation of
stars in the various evolutionary stages. The counts of AGB stars brighter than
the RGB tip allow us to estimate the star formation at intermediate ages.
Assuming a Salpeter initial mass function, we find that the star formation
episode at intermediate ages produced ~6x10^5 M_sun of stars in the observed
region.


title:
Is there a non-Standard-Model contribution in non-leptonic b -> s
  decays?

abstract:
  Precision measurements of branching fractions and CP asymmetries in
non-leptonic b -> s decays reveal certain "puzzles" when compared with Standard
Model expectations based on a global fit of the CKM triangle and general
theoretical expectations. Without reference to a particular model, we
investigate to what extent the (small) discrepancies observed in (B -> J/psi
K), (B -> phi K) and (B -> K pi) may constrain new physics in (b -> s q qbar)
operators. In particular, we compare on a quantitative level the relative
impact of different quark flavours q=c,s,u,d.


title:
Effective models and extension of torsors over a discrete valuation ring
  of unequal characteristic

abstract:
  Let R be a discrete valuation ring of unequal characteristic with fraction
field K which contains a primitive p^2-th root of unity. Let X be a faithfully
flat R-scheme and G be a finite abstract group. Let us consider a G-torsor
Y_K\to X_K and let Y be the normalization of X_K in Y. If G=Z/p^n Z, n<3, under
some hypothesis on X, we attach some invariants to Y_K \to X_K. If p>2, we
determine, through these invariants, when Y\to X has a structure of torsor
which extends that of Y_K\to X_K. Moreover we explicitly calculate the
effective model (defined by Romagny) of the action of G on Y.


title: Polarised infrared emission from X-ray binary jets

abstract:
  Near-infrared (NIR) and optical polarimetric observations of a selection of
X-ray binaries are presented. The targets were observed using the Very Large
Telescope and the United Kingdom Infrared Telescope. We detect a significant
level (3 sigma) of linear polarisation in four sources. The polarisation is
found to be intrinsic (at the > 3 sigma level) in two sources; GRO J1655-40 (~
4-7% in H and Ks-bands during an outburst) and Sco X-1 (~ 0.1-0.9% in H and K),
which is stronger at lower frequencies. This is likely to be the signature of
optically thin synchrotron emission from the collimated jets in these systems,
whose presence indicates a partially-ordered magnetic field is present at the
inner regions of the jets. In Sco X-1 the intrinsic polarisation is variable
(and sometimes absent) in the H and K-bands. In the J-band (i.e. at higher
frequencies) the polarisation is not significantly variable and is consistent
with an interstellar origin. The optical light from GX 339-4 is also polarised,
but at a level and position angle consistent with scattering by interstellar
dust. The other polarised source is SS 433, which has a low level (0.5-0.8%) of
J-band polarisation, likely due to local scattering. The NIR counterparts of
GRO J0422+32, XTE J1118+480, 4U 0614+09 and Aql X-1 (which were all in or near
quiescence) have a linear polarisation level of < 16% (3 sigma upper limit,
some are < 6%). We discuss how such observations may be used to constrain the
ordering of the magnetic field close to the base of the jet in such systems.


title: Structure of the cuspidal rational torsion subgroup of J_1(p^n)

abstract:
  In this article, we determine the structure of the $p$-primary subgroup of
the cuspidal rational torsion subgroup of the Jacobian $J_1(p^n)$ of the
modular curve $X_1(p^n)$ for a regular prime $p$.


Comment on ``Tests of scaling and universality of the distributions of
  trade size and share volume: Evidence from three distinct markets" by Plerou
  and Stanley, Phys. Rev. E 76, 046109 (2007)


title:
The Einstein-Maxwell Equations, Extremal Kahler Metrics, and
  Seiberg-Witten Theory

abstract:
  The Einstein-Maxwell equations on a smooth compact 4-manifold are
reformulated as a purely Riemannian variational problem analogous to Calabi's
variational problem for extremal Kahler metrics. Next, Seiberg-Witten theory is
used to show that these two problems are in fact intimately related. Extremal
Kahler metrics are then used to probe the limits of Seiberg-Witten curvature
estimates. The article then concludes with a brief survey of some recent
results on extremal Kahler metrics.


title: The classical hydrodynamics of the Calogero-Sutherland model

abstract:
  We explore the classical version of the mapping, due to Abanov and Wiegmann,
of Calogero-Sutherland hydrodynamics onto the Benjamin-Ono equation ``on the
double.'' We illustrate the mapping by constructing the soliton solutions to
the hydrodynamic equations, and show how certain subtleties arise from the need
to include corrections to the naive replacement of singular sums by
principal-part integrals.


title:
Electric field switching of antiferromagnetic domains in YMn2O5: a probe
  of the multiferroic mechanism

abstract:
  We employ neutron spherical polarimetry to determine the nature and
population of the coexisting antiferromagnetic domains in multiferroic YMn2O5.
By applying an electric field, we prove that reversing the electrical
polarization results in the population inversion of two types of in-plane
domains, related to each other by inversion. Our results are completely
consistent with the exchange striction mechanism of ferroelectricity, and
support a unified model where cycloidal ordering is induced by coupling to the
main magnetic order parameter.


title: On sums of primes and triangular numbers

abstract:
  We study whether sufficiently large integers can be written in the form
cp+T_x, where p is either zero or a prime congruent to r mod d, and
T_x=x(x+1)/2 is a triangular number. We also investigate whether there are
infinitely many positive integers not of the form (2^ap-r)/m+T_x with p a prime
and x an integer. Besides two theorems, the paper also contains several
conjectures together with related analysis and numerical data. One of our
conjectures states that each natural number not equal to 216 can be written in
the form p+T_x with x an integer and p a prime or zero; another conjecture
asserts that any odd integer n>3 can be written in the form p+x(x+1) with p a
prime and x a positive integer.


title: Searching optimal shapes for blades of a fan

abstract:
  A nonlinear differential equation about optimal shapes for blades of a fan. A
boundary value differential problem from engineering, geometrical or physical
bonds. A relation between linear profiles and constant speed along the side
under flow.


title:
Eigenvalue and Dirichlet problem for fully-nonlinear operators in non
  smooth domains

abstract:
  In this paper we study the maximum principle, the existence of eigenvalue and
the existence of solution for the Dirichlet problem for operators which are
fully-nonlinear, elliptic but presenting some singularity or degeneracy which
are similar to those of the p-Laplacian, the novelty resides in the fact that
we consider the equations in bounded domains which only satisfy the exterior
cone condition.


title: False discovery rate analysis of brain diffusion direction maps

abstract:
  Diffusion tensor imaging (DTI) is a novel modality of magnetic resonance
imaging that allows noninvasive mapping of the brain's white matter. A
particular map derived from DTI measurements is a map of water principal
diffusion directions, which are proxies for neural fiber directions. We
consider a study in which diffusion direction maps were acquired for two groups
of subjects. The objective of the analysis is to find regions of the brain in
which the corresponding diffusion directions differ between the groups. This is
attained by first computing a test statistic for the difference in direction at
every brain location using a Watson model for directional data. Interesting
locations are subsequently selected with control of the false discovery rate.
More accurate modeling of the null distribution is obtained using an empirical
null density based on the empirical distribution of the test statistics across
the brain. Further, substantial improvements in power are achieved by local
spatial averaging of the test statistic map. Although the focus is on one
particular study and imaging technology, the proposed inference methods can be
applied to other large scale simultaneous hypothesis testing problems with a
continuous underlying spatial structure.


title: From cardinal spline wavelet bases to highly coherent dictionaries

abstract:
  Wavelet families arise by scaling and translations of a prototype function,
called the {\em {mother wavelet}}. The construction of wavelet bases for
cardinal spline spaces is generally carried out within the multi-resolution
analysis scheme. Thus, the usual way of increasing the dimension of the
multi-resolution subspaces is by augmenting the scaling factor. We show here
that, when working on a compact interval, the identical effect can be achieved
without changing the wavelet scale but reducing the translation parameter. By
such a procedure we generate a redundant frame, called a {\em{dictionary}},
spanning the same spaces as a wavelet basis but with wavelets of broader
support. We characterise the correlation of the dictionary elements by
measuring their `coherence' and produce examples illustrating the relevance of
highly coherent dictionaries to problems of sparse signal representation.


title: Network protocol scalability via a topological Kadanoff transformation

abstract:
  A natural hierarchical framework for network topology abstraction is
presented based on an analogy with the Kadanoff transformation and
renormalisation group in theoretical physics. Some properties of the
renormalisation group bear similarities to the scalability properties of
network routing protocols (interactions). Central to our abstraction are two
intimately connected and complementary path diversity units: simple cycles, and
cycle adjacencies. A recursive network abstraction procedure is presented,
together with an associated generic recursive routing protocol family that
offers many desirable features.


title: Einstein Metrics, Complex Surfaces, and Symplectic 4-Manifolds

abstract:
  Which smooth compact 4-manifolds admit an Einstein metric with non-negative
Einstein constant? A complete answer is provided in the special case of
4-manifolds that also happen to admit either a complex structure or a
symplectic structure.


title: The Berry phase in frustrated spin glass

abstract:
  In this letter we have pointed out that frustration in spin glass is realized
through the Berry phase due to the conflict between the spin ordering in the
course of parallel transport of spinor. We have came to the point that the
Berry phase depicting the chiral change of helicity of a quantized spinor is
prominent only in the presence of frustration.


title: Qubit rotation in QHE

abstract:
  In Quantum Hall effect the ground state wave function at $\nu=1$ is the
building block of all other states at different filling factors. It is
developed by the entanglement of two spinors forming a singlet state. The
inherent frustration visualized by the non-abelian matrix Berry phase is
responsible for the quantum pumped charge to flow in the Hall surface. The
Physics behind the Quantum Hall states is studied here from the view point of
topological quantum computation.


title: Cluster Approach to the Domains Formation

abstract:
  As a rule, a quadratic functional depending on a great number of binary
variables has a lot of local minima. One of approaches allowing one to find in
averaged deeper local minima is aggregation of binary variables into larger
blocks/domains. To minimize the functional one has to change the states of
aggregated variables (domains). In the present publication we discuss methods
of domains formation. It is shown that the best results are obtained when
domains are formed by variables that are strongly connected with each other.


title: One-particle irreducibility with initial correlations

abstract:
  In quantum field theory (QFT), the vacuum expectation value of a normal
product of creation and annihilation operators is always zero. This simple
property paves the way to the classical treatment of perturbative QFT. This is
no longer the case in the presence of initial correlations, that is if the
vacuum is replaced by a general state. As a consequence, the combinatorics of
correlated systems such as the ones occurring in many-body physics is more
complex than that of quantum field theory and the general theory has made very
slow progress. Similar observations hold in statistical physics or quantum
probability for the perturbation series arising from the study of non Gaussian
measures. In this work, an analysis of the Hopf algebraic aspects of quantum
field theory is used to derive the structure of Green functions in terms of
connected and one-particle irreducible Greeen functions for perturbative QFT in
the presence of initial correlations.


title:
Transcience/recurrence for normally reflected Brownian motion in
  unbounded domains

abstract:
  Let $D\subsetneq R^d$ be an unbounded domain and let $B(t)$ be a Brownian
motion in $D$ with normal reflection at the boundary. We study the
transcience/recurrence dichotomy, focusing mainly on domains of the form
$D=\{(x,z)\in R^{l+m}:|z|<H(|x|)\}$, where $d=l+m$ and $H$ is a sufficiently
regular function. This class of domains includes various horn-shaped domains
and generalized slab domains.


title:
Photoproduction of H$_3^+$ from gaseous methanol inside dense molecular
  clouds

abstract:
  We present experimental results obtained from photoionization and
photodissociation processes of abundant interstellar methanol (CH$_3$OH) as an
alternative route for the production of H$_3^+$ in dense clouds. The
measurements were taken at the Brazilian Synchrotron Light Laboratory (LNLS)
employing soft X-ray and time-of-flight mass spectrometry. Mass spectra were
obtained using the photoelectron-photoion coincidence techniques. Absolute
averaged cross sections for the production of H$_3^+$ due to molecular
dissociation of methanol by soft X-rays (C1s edge) were determined. The
H$_3^+$'s photoproduction rate and column density were been estimated adopting
a typical soft X-ray luminosity inside dense molecular and the observed column
density of methanol. Assuming a steady state scenario, the highest column
density value for the photoproduced H$_3^+$ was about 10$^{11}$ cm$^2$, which
gives the ratio photoproduced/observed of about 0.05%, as in the case of dense
molecular cloud AFGL 2591. Despite the small value, this represent a new and
alternative source of H$_3^+$ into dense molecular clouds and it is not been
considered as yet in interstellar chemistry models.


title: The Fourier spectrum of critical percolation

abstract:
  Consider the indicator function $f$ of a two-dimensional percolation crossing
event. In this paper, the Fourier transform of $f$ is studied and sharp bounds
are obtained for its lower tail in several situations. Various applications of
these bounds are derived. In particular, we show that the set of exceptional
times of dynamical critical site percolation on the triangular grid in which
the origin percolates has dimension 31/36 a.s., and the corresponding dimension
in the half-plane is 5/9. It is also proved that critical bond percolation on
the square grid has exceptional times a.s. Also, the asymptotics of the number
of sites that need to be resampled in order to significantly perturb the global
percolation configuration in a large square is determined.


title:
Survival of gas phase amino acids and nucleobases in space radiation
  conditions

abstract:
  We present experimental studies on the photoionization and photodissociation
processes (photodestruction) of gaseous amino acids and nucleobases in
interstellar and interplanetary radiation conditions analogs. The measurements
have been undertaken at the Brazilian Synchrotron Light Laboratory (LNLS),
employing vacuum ultraviolet (VUV) and soft X-ray photons. The experimental set
up basically consists of a time-of-flight mass spectrometer kept under high
vacuum conditions. Mass spectra were obtained using photoelectron photoion
coincidence technique. We have shown that the amino acids are effectively more
destroyed (up to 70-80%) by the stellar radiation than the nucleobases, mainly
in the VUV. Since polycyclic aromatic hydrocarbons have the same survival
capability and seem to be ubiquitous in the ISM, it is not unreasonable to
predict that nucleobases could survive in the interstellar medium and/or in
comets, even as a stable cation.


title: Charmed meson rescattering in the reaction pbar d to D Dbar N

abstract:
  We examine the possibility to extract information about the DN and DbarN
interactions from the pbar d to D Dbar N reaction. We utilize the notion that
the open-charm mesons are first produced in the annihilation of the antiproton
on one nucleon in the deuteron and subsequently rescatter on the other (the
spectator) nucleon. The latter process is then exploited for investigating the
DN and DbarN interactions. We study different methods for isolating the
contributions from the D^0p and D^-p rescattering terms.


title: Conditional Haar measures on classical compact groups

abstract:
  We give a probabilistic proof of the Weyl integration formula on U(n), the
unitary group with dimension $n$. This relies on a suitable definition of Haar
measures conditioned to the existence of a stable subspace with any given
dimension $p$. The developed method leads to the following result: for this
conditional measure, writing $Z_U^{(p)}$ for the first nonzero derivative of
the characteristic polynomial at 1,
\[\frac{Z_U^{(p)}}{p!}\stackrel{\mathrm{law}}{=}\prod_{\ell
=1}^{n-p}(1-X_{\ell}),\] the $X_{\ell}$'s being explicit independent random
variables. This implies a central limit theorem for $\log Z_U^{(p)}$ and
asymptotics for the density of $Z_U^{(p)}$ near 0. Similar limit theorems are
given for the orthogonal and symplectic groups, relying on results of Killip
and Nenciu.


title:
Efficient evaluation of the Fourier Transform over products of
  Slater-type orbitals on different centers

abstract:
  Using the shift-operator technique, a compact formula for the Fourier
transform of a product of two Slater-type orbitals located on different atomic
centers is derived. The result is valid for arbitrary quantum numbers and was
found to be numerically stable for a wide range of geometrical parameters and
momenta. Details of the implementation are presented together with benchmark
data for representative integrals. We also discuss the assets and drawbacks of
alternative algorithms available and analyze the numerical efficiency of the
new scheme.


title: Using relaxational dynamics to reduce network congestion

abstract:
  We study the effects of relaxational dynamics on congestion pressure in scale
free networks by analyzing the properties of the corresponding gradient
networks (Z. Toroczkai, K. E. Bassler, Nature {\bf 428}, 716 (2004)). Using the
Family model (F. Family, J. Phys. A, {\bf 19}, L441 (1986)) from surface-growth
physics as single-step load-balancing dynamics, we show that the congestion
pressure considerably drops on scale-free networks when compared with the same
dynamics on random graphs. This is due to a structural transition of the
corresponding gradient network clusters, which self-organize such as to reduce
the congestion pressure. This reduction is enhanced when lowering the value of
the connectivity exponent $\lambda$ towards 2.


title: Statistical Physics Approaches to Seismicity

abstract:
  This entry in the Encyclopedia of Complexity and Systems Science, Springer
present a summary of some of the concepts and calculational tools that have
been developed in attempts to apply statistical physics approaches to
seismology. We summarize the leading theoretical physical models of the
space-time organization of earthquakes. We present a general discussion and
several examples of the new metrics proposed by statistical physicists,
underlining their strengths and weaknesses. The entry concludes by briefly
outlining future directions. The presentation is organized as follows. I
Glossary II Definition and Importance of the Subject III Introduction IV
Concepts and Calculational Tools IV.1 Renormalization, Scaling and the Role of
Small Earthquakes in Models of Triggered Seismicity IV.2 Universality IV.3
Intermittent Periodicity and Chaos IV.4 Turbulence IV.5 Self-Organized
Criticality V Competing mechanisms and models V.1 Roots of complexity in
seismicity: dynamics or heterogeneity? V.2 Critical earthquakes V.3 Spinodal
decomposition V.4 Dynamics, stress interaction and thermal fluctuation effects
VI Empirical studies of seismicity inspired by statistical physics VI.1 Early
successes and latter subsequent challenges VI.2 Entropy method for the
distribution of time intervals between mainshocks VI.3 Scaling of the PDF of
Waiting Times VI.4 Scaling of the PDF of Distances Between Subsequent
Earthquakes VI.5 The Network Approach VII Future Directions


title: On regression adjustments in experiments with several treatments

abstract:
  Regression adjustments are often made to experimental data. Since
randomization does not justify the models, bias is likely; nor are the usual
variance calculations to be trusted. Here, we evaluate regression adjustments
using Neyman's nonparametric model. Previous results are generalized, and more
intuitive proofs are given. A bias term is isolated, and conditions are given
for unbiased estimation in finite samples.


title: Stability of Delayed Systems Modeled by Fractional Models

abstract:
  The paper discusses linear fractional representations of parameter-dependent
nonlinear systems with dynamics defined by real rational nonlinearities and a
finite set of point delays. The global asymptotic stability is investigated via
linear matrix inequalities.


title: The Hertz/VPM polarimeter: Design and first light observations

abstract:
  We present first results of Hertz/VPM, the first submillimeter polarimeter
employing the dual Variable-delay Polarization Modulator (dual-VPM). This
device differs from previously used polarization modulators in that it operates
in translation rather than mechanical rotation. We discuss the basic theory
behind this device, and its potential advantages over the commonly used half
wave plate (HWP). The dual-VPM was tested both at the Submillimeter Telescope
Observatory (SMTO) and in the lab. In each case we present a detailed
description of the setup. We discovered nonideal behavior in the system. This
is at least in part due to properties of the VPM wire grids (diameter, spacing)
employed in our experiment. Despite this, we found that the dual-VPM system is
robust, operating with high efficiency and low instrumental polarization. This
device is well suited for air and space-borne applications.


title: Remark on laser linewidth hazard in opto-mechanical cooling

abstract:
  I discuss the robustness of the pumped cavity dynamics against phase
diffusion of the laser and conclude that opto-mechanical cooling has extreme
sensitivity compared to laser cooling of atoms. Certain proposals of ground
state opto-mechanical cooling by single cavity would require an unrealistic
sharp laser linewidth or equivalently, a very low level of phase noise. A
systematic way to cancel classical excess phase noise is the interferometric
twin-cavity pumping, initiated for optically trapped macro-mirrors of future
gravitational-wave detectors.


title: Anomalous Diffusion In Microrheology: A Comparative Study

abstract:
  We present a comparative study on two theoretical descriptions of
microrheological experiments. Using a generalized Langevin equation (GLE), we
analyze the origin of the power-law behavior of the main properties of a
viscoelastic medium. Then, we discuss the equivalence of the GLE with a
generalized Fokker-Planck equation (GFPE), and how more general GFPE's can be
derived from a thermo-kinetic formalism. These complementary theories lead to a
justification for the physical nature of the Hurst exponent of fractional
kinetics. Theory is compared with experiments.


title:
Prospects for cosmic neutrino detection in tritium experiments in the
  case of hierarchical neutrino masses

abstract:
  We discuss the effects of neutrino mixing and the neutrino mass hierarchy
when considering the capture of the cosmic neutrino background (CNB) on
radioactive nuclei. The implications of mixing and hierarchy at future
generations of tritium decay experiments are considered. We find that the CNB
should be detectable at these experiments provided that the resolution for the
kinetic energy of the outgoing electron can be pushed to a few 0.01 eV for the
scenario with inverted neutrino mass hierarchy, about an order of magnitude
better than that of the upcoming KATRIN experiment. Another order of magnitude
improvement is needed in the case of normal neutrino mass hierarchy. We also
note that mixing effects generally make the prospects for CNB detection worse
due to an increased maximum energy of the normal beta decay background.


title:
Mechanics of complex bodies: commentary on the unified modelling of
  material substructures

abstract:
  Basic issues of the general model-building framework of the mechanics of
complex bodies are discussed. Attention is focused on the representation of the
material elements, the conditions for the existence of ground states in
conservative setting and the interpretation of the nature of the various
balance laws occurring.


title:
Cohomology and generic cohomology of Specht modules for the symmetric
  group

abstract:
  Cohomology of Specht modules for the symmetric group can be equated in low
degrees with corresponding cohomology for the Borel subgroup B of the general
linear group GL_d(k), but this has never been exploited to prove new symmetric
group results. Using work of Doty on the submodule structure of symmetric
powers of the natural GL_d(k) module together with work of Andersen on
cohomology for B and its Frobenius kernels, we prove new results about
H^i(\Sigma_d, S^\lambda). We recover work of James in the case i=0. Then we
prove two stability theorems, one of which is a "generic cohomology" result for
Specht modules equating cohomology of S^{p\lambda} with S^{p^2\lambda}. This is
the first theorem we know relating Specht modules S^\lambda and S^{p\lambda}.
The second result equates cohomology of S^\lambda with S^{\lambda + p^a\mu} for
large a.


title: Superconductivity in Ca-intercalated bilayer graphene

abstract:
  Recent observation of proximity effect \cite{Morpurgo:2007} has ignited
interest in superconductivity in graphene and its derivatives. We consider
Ca-intercalated graphene bilayer and argue that it is a superconductor, and
likely with a sizeable $T_{c}$. We find substantial and suggestive similarities
between Ca-intercalated bilayer (C$_{6}$CaC$_{6}$), and CaC$_{6} $, an
established superconductor with $T_{c}$ = 11.5 K. In particular, the nearly
free electron band, proven to be instrumental for superconductivity in
intercalated graphites, does cross the chemical potential in (C$_{6}$CaC$%
_{6}$), despite the twice smaller doping level, satisfying the so-called
\textquotedblleft Cambridge criterion\textquotedblright . Calculated properties
of zone-center phonons are very similar to those of CaC$%_{6}.$ This suggests
that the critical temperature would probably be on the same scale as in
CaC$_{6}$.


title: The Quantum McKay Correspondence for polyhedral singularities

abstract:
  Let G be a polyhedral group, namely a finite subgroup of SO(3). Nakamura's
G-Hilbert scheme provides a preferred Calabi-Yau resolution Y of the polyhedral
singularity C^3/G. The classical McKay correspondence describes the classical
geometry of Y in terms of the representation theory of G. In this paper we
describe the quantum geometry of Y in terms of R, an ADE root system associated
to G. Namely, we give an explicit formula for the Gromov-Witten partition
function of Y as a product over the positive roots of R. In terms of counts of
BPS states (Gopakumar-Vafa invariants), our result can be stated as a
correspondence: each positive root of R corresponds to one half of a genus zero
BPS state. As an application, we use the crepant resolution conjecture to
provide a full prediction for the orbifold Gromov-Witten invariants of [C^3/G].


title:
Asymptotics of Toeplitz Matrices with Symbols in Some Generalized Krein
  Algebras

abstract:
  Let $\alpha,\beta\in(0,1)$ and \[ K^{\alpha,\beta}:=\left\{a\in L^\infty(\T):
\sum_{k=1}^\infty |\hat{a}(-k)|^2 k^{2\alpha}<\infty, \sum_{k=1}^\infty
|\hat{a}(k)|^2 k^{2\beta}<\infty \right\}. \] Mark Krein proved in 1966 that
$K^{1/2,1/2}$ forms a Banach algebra. He also observed that this algebra is
important in the asymptotic theory of finite Toeplitz matrices. Ten years
later, Harold Widom extended earlier results of Gabor Szeg\H{o} for scalar
symbols and established the asymptotic trace formula \[
\operatorname{trace}f(T_n(a))=(n+1)G_f(a)+E_f(a)+o(1) \quad\text{as}\
n\to\infty \] for finite Toeplitz matrices $T_n(a)$ with matrix symbols $a\in
K^{1/2,1/2}_{N\times N}$. We show that if $\alpha+\beta\ge 1$ and $a\in
K^{\alpha,\beta}_{N\times N}$, then the Szeg\H{o}-Widom asymptotic trace
formula holds with $o(1)$ replaced by $o(n^{1-\alpha-\beta})$.


title: Reciprocity of gauge operators in N=4 SYM

abstract:
  A recently discovered generalized Gribov-Lipatov reciprocity holds for the
anomalous dimensions of various twist operators in N=4 SYM. Here, we consider a
class of scaling psu(2,2|4) operators that reduce at one-loop to twist-3
maximal helicity gluonic operators. We extract from the asymptotic long-range
Bethe Ansatz a closed expression for the spin dependent anomalous dimension at
four loop order and provide a complete proof of reciprocity. We comment about
the interplay with possible, yet unknown, wrapping corrections.


title: Quantum Bounded Symmetric Domains

abstract:
  This is Leonid Vaksman's monograph "Quantum bounded symmetric domains" (in
Russian), preceded with an English translation of the table of contents and (a
part) of the introduction.
  Quantum bounded symmetric domains are interesting from several points of
view. In particular, they provide interesting examples for noncommutative
complex analysis (i.e., the theory of subalgebras of C^*-algebars) initiated by
W. Arveson.


title: The Quantum Nature of a Nuclear Phase Transition

abstract:
  In their ground states, atomic nuclei are quantum Fermi liquids. At finite
temperatures and low densities, these nuclei may undergo a phase change similar
to, but substantially different from, a classical liquid gas phase transition.
As in the classical case, temperature is the control parameter while density
and pressure are the conjugate variables. At variance with the classical case,
in the nucleus the difference between the proton and neutron concentrations
acts as an additional order parameter, for which the symmetry potential is the
conjugate variable. Different ratios of the neutron to proton concentrations
lead to different critical points for the phase transition. This is analogous
to the phase transitions occurring in $^{4}$He-$^{3}$He liquid mixtures. We
present experimental results which reveal the N/Z dependence of the phase
transition and discuss possible implications of these observations in terms of
the Landau Free Energy description of critical phenomena.