title: Diffusion on a heptagonal lattice

abstract:
  We study the diffusion phenomena on the negatively curved surface made up of
congruent heptagons. Unlike the usual two-dimensional plane, this structure
makes the boundary increase exponentially with the distance from the center,
and hence the displacement of a classical random walker increases linearly in
time. The diffusion of a quantum particle put on the heptagonal lattice is also
studied in the framework of the tight-binding model Hamiltonian, and we again
find the linear diffusion like the classical random walk. A comparison with
diffusion on complex networks is also made.


title:
The asymptotically optimal estimating equation for longitudinal data.
  Strong Consistency

abstract:
  In this article, we introduce a conditional marginal model for longitudinal
data, in which the residuals form a martingale difference sequence. This model
allows us to consider a rich class of estimating equations, which contains
several estimating equations proposed in the literature. A particular sequence
of estimating equations in this class contains a random matrix
$\mathcal{R}_{i-1}^*(\beta)$, as a replacement for the ``true'' conditional
correlation matrix of the $i$-th individual. Using the approach of [12], we
identify some sufficient conditions under which this particular sequence of
equations is asymptotically optimal (in our class). In the second part of the
article, we identify a second set of conditions, under which we prove the
existence and strong consistency of a sequence of estimators of $\beta$,
defined as roots of estimation equations which are martingale transforms (in
particular, roots of the sequence of asymptotically optimal equations).


title:
Electromagnetic Mean Squared Radii of Lambda(1405) in Meson-baryon
  Dynamics with Chiral Symmetry

abstract:
  Electromagnetic mean squared radii of Lambda(1405) are evaluated in chiral
unitary approach. In this approach we regard Lambda(1405) as dynamically
generated resonances in the octet meson and octet baryon scattering, and also
as KbarN bound state. Especially for the Lambda(1405) as KbarN bound state we
obtain negative electric mean squared radius. With the small binding energy of
Lambda(1405) in the chiral unitary approach, our results imply that
Lambda(1405) has structure that K^- is widely spread around p.


title: Is QGP really a liquid ?

abstract:
  Here we address the question regarding the nature of quark gluon plasma
(QGP), whether it is a liquid or strongly coupled plasma (SCP), using two
different phenomenological models, namely quasi-particle model (qQGP) and
strongly coupled quark gluon plasma (SCQGP). First we compare these two models,
both of which explains the results of lattice simulation of quantum
chromodynamics, as a function of plasma parameter and conclude that the QGP is
largely ($T > 1.5 T_c$) SCQGP and only for $T < 1.5 T_c$ it may be a liquid.


title:
Fe K alpha and hydrodynamic loop model diagnostics for a large flare on
  II Peg

abstract:
  The observation by the Swift X-ray Telescope of the Fe K alpha_1, alpha_2
doublet during a large flare on the RS CVn binary system II Peg represents one
of only two firm detections to date of photospheric Fe K alpha from a star
other than our Sun. We present models of the Fe K alpha equivalent widths
reported in the literature for the II Peg observations and show that they are
most probably due to fluorescence following inner shell photoionisation of
quasi-neutral Fe by the flare X-rays. Our models constrain the maximum height
of flare the to 0.15 R_* assuming solar abundances for the photospheric
material, and 0.1 R_* and 0.06 R_* assuming depleted photospheric abundances
([M/H]=-0.2 and [M/H]=-0.4, respectively). Accounting for an extended loop
geometry has the effect of increasing the estimated flare heights by a factor
of ~3. These predictions are consistent with those derived using results of
flaring loop models, which are also used to estimate the flaring loop
properties and energetics. From loop models we estimate a flare loop height of
0.13 R_*, plasma density of ~4 * 10^12 cm^-3 and emitting volume of ~6 * 10^30
cm^3. Our estimates for the flare dimensions and density allow us to estimate
the conductive energy losses to E_cond <= 2 * 10^36 erg, consistent with upper
limits previously obtained in the literature. Finally, we estimate the average
energy output of this large flare to be ~10^33 erg sec^-1, or 1/10th of the
stellar bolometric luminosity.


title: Numerical study of the frustrated ferromagnetic spin-1/2 chain

abstract:
  The ground state phase diagram of the frustrated ferromagnetic spin-1/2 chain
is investigated using the exact diagonalization technique. It is shown that
there is a jump in the spontaneous magnetization and the ground state of the
system undergos to a phase transition from a ferromagnetic phase to a phase
with dimer ordering between next-nearest-neighbor spins. Near the quantum
transition point, the critical behavior of the ground state energy is analyzed
numerically. Using a practical finite-size scaling approach, the critical
exponent of the ground state energy is computed. Our numerical results are in
good agreement with the results obtained by other theoretical approaches.


title: The String bordism of $BE_8$ and $BE_8\times BE_8$ through dimension 14

abstract:
  We compute the low dimensional String bordism groups of $BE_8$ and
$BE_8\times BE_8$ using a combination of Adams spectral sequences together with
comparisons to the Spin bordism cases.


title: A Bernstein-Von Mises Theorem for discrete probability distributions

abstract:
  We investigate the asymptotic normality of the posterior distribution in the
discrete setting, when model dimension increases with sample size. We consider
a probability mass function $\theta_0$ on $\mathbbm{N}\setminus \{0\}$ and a
sequence of truncation levels $(k_n)_n$ satisfying $k_n^3\leq n\inf_{i\leq
k_n}\theta_0(i).$ Let $\hat{\theta}$ denote the maximum likelihood estimate of
$(\theta_0(i))_{i\leq k_n}$ and let $\Delta_n(\theta_0)$ denote the
$k_n$-dimensional vector which $i$-th coordinate is defined by \sqrt{n}
(\hat{\theta}_n(i)-\theta_0(i)) for $1\leq i\leq k_n.$ We check that under mild
conditions on $\theta_0$ and on the sequence of prior probabilities on the
$k_n$-dimensional simplices, after centering and rescaling, the variation
distance between the posterior distribution recentered around $\hat{\theta}_n$
and rescaled by $\sqrt{n}$ and the $k_n$-dimensional Gaussian distribution
$\mathcal{N}(\Delta_n(\theta_0),I^{-1}(\theta_0))$ converges in probability to
$0.$ This theorem can be used to prove the asymptotic normality of Bayesian
estimators of Shannon and R\'{e}nyi entropies. The proofs are based on
concentration inequalities for centered and non-centered Chi-square (Pearson)
statistics. The latter allow to establish posterior concentration rates with
respect to Fisher distance rather than with respect to the Hellinger distance
as it is commonplace in non-parametric Bayesian statistics.


title: Testing a priority-based queue model with Linux command histories

abstract:
  We study human dynamics by analyzing Linux history files. The goodness-of-fit
test shows that most of the collected datasets belong to the universality class
suggested in the literature by a variable-length queueing process based on
priority. In order to check the validity of this model, we design two tests
based on mutual information between time intervals and a mathematical
relationship known as the arcsine law. Since the previously suggested queueing
process fails to pass these tests, the result suggests that the modelling of
human dynamics should properly consider the statistical dependency in the
temporal dimension.


title:
Spectroscopic Observations of WZ Sge-type Dwarf Novae, GW Lib and V455
  And in Superoutburst

abstract:
  We carried out intensive spectroscopic observations of two WZ Sge-type dwarf
novae, GW Lib, and V455 And during their superoutbursts in 2007, at 6
observatories. The observations covered the whole of both superoutbursts from
the very maximum to the fading tail. We found evidence of the winds having a
speed of $\sim$1000 km s$^{-1}$ which blew in GW Lib during the rising phase.
The evolution of the hydrogen, helium, and carbon lines suggests flaring of the
accretion disk and emergence of the temperature inversion layer on the disk.


title: The 8-universality Criterion is Unique

abstract:
  Using the methods developed for the proof that the 2-universality criterion
is unique, we partially characterize criteria for the n-universality of
positive-definite integer-matrix quadratic forms. We then obtain the uniqueness
of Oh's 8-universality criterion as an application of our characterization
results.


title: The Stein hull

abstract:
  We are interested in the statistical linear inverse problem
$Y=Af+\epsilon\xi$, where $A$ denotes a compact operator and $\epsilon\xi$ a
stochastic noise. In a first time, we investigate the link between some
threshold estimators and the risk hull point of view introduced in (5). The
penalized blockwise Stein's rule plays a central role in this study. In
particular, this estimator may be considered as a risk hull minimization
method, provided the penalty is well-chosen. Using this perspective, we study
the properties of the threshold and propose an admissible range for the penalty
leading to accurate results. We eventually propose a penalty close to the lower
bound of this range. The risk hull point of view provides interesting tools for
the construction of adaptive estimators. It sheds light on the processes
governing the behavior of linear estimators. The variability of the problem may
be indeed quite large and should be carefully controlled.


title: Response of 3D Free Axisymmetric Rigid Objects under Seismic Excitations

abstract:
  Previous studies of precariously balanced objects in seismically active
regions provide important information for aseismatic engineering and
theoretical seismology. They are almost founded on an oversimplified
assumption: any 3-dimensional (3D) actual object with special symmetry could be
regarded as a 2D finite object in light of the corresponding symmetry. To gain
an actual evolution of precariously balanced objects subjected to various
levels of ground accelerations, a 3D investigation should be performed. In
virtue of some reasonable works from a number of mechanicians, we derive three
resultant second-order ordinary differential equations determine the evolution
of 3D responses. The new dynamic analysis is following the 3D rotation of a
rigid body around a fixed point. A computer program for numerical solution of
these equations is also developed to simulate the rocking and rolling response
of axisymmetric objects to various levels of ground accelerations. It is shown
that the 2D and 3D estimates on the minimum overturning acceleration of a
cylinder under the same sets of half- and full-sine-wave pulses are almost
consistent except at several frequency bonds. However, we find that the 2D and
3D responses using the actual seismic excitation have distinct differences,
especially to north-south (NS) and up-down (UD) components. In this work the
chosen seismic wave is the El Centro recording of the 18 May 1940 Imperial
Valley Earthquake. The 3D outcome does not seem to support the 2D previous
result that the vertical component of the ground acceleration is less important
than the horizontal ones. We conclude that the 2D dynamic modeling is not
always reliable.


title: The total mass and dark halo properties of the Small Magellanic Cloud

abstract:
  We discuss the total mass and dark halo properties of the Small Magellanic
Cloud (SMC) for reasonable $V$-band stellar-to-mass-to-light ratios ($M_{\rm
s}/L_{\rm V}$) based on the high-resolution neutral hydrogen (HI) observations
of the SMC. We adopt both the Burkert and the NFW profiles for the dark matter
halo of the SMC in order to model the radial profile of the observed rotation
curve. We show that the mass ($M_{\rm dm}$) and the mean density (${\rho}_{\rm
dm}$) of the dark matter halo within the optical radius ($\sim 3$ kpc) of the
SMC can be significantly low for $M_{\rm s}/L_{\rm V}=2-4$ reasonable for a
galaxy dominated by older stellar populations. For example, the estimated
$M_{\rm dm}$ and ${\rho}_{\rm dm}$ are $7.5 \times 10^7 {\rm M}_{\odot}$ and
$6.7 \times 10^{-4} {\rm M}_{\odot}$ pc$^{-3}$, respectively, for $M_{\rm
s}/L_{\rm V} = 3.8$. The models with lower $M_{\rm s}/L_{\rm V}$ ($<1.0$) can
show higher $M_{\rm dm}$ and ${\rho}_{\rm dm}$ yet have difficulties in
reproducing the inner rotation curve profile both for the Burkert and the NFW
profiles. The Burkert profile with a larger core radius ($>1$ kpc) (thus a low
density) and a large mass (${\rm M}_{\rm dm} > 3 \times 10^9 {\rm M}_{\odot}$)
can be better fit to the observed slowly rising rotation curve than the NFW one
for a reasonable $M_{\rm s}/L_{\rm V} \sim2$. This means that most of the dark
halo mass can be initially located outside the optical radius in the SMC and
thus that the dark halo would have already lost a significant fraction of its
original mass due to the strong tidal interactions with the Galaxy and possibly
with the Large Magellanic Cloud (LMC).


title: The Fate of Young Radio Galaxies: Decelerations Inside Host Galaxies?

abstract:
  We examine the evolution of variously-sized radio galaxies [i.e., compact
symmetric objects (CSOs), medium-size symmetric objects (MSOs), Fanaroff-Riley
type II radio galaxies (FRIIs)], by comparing the relation between the hot spot
size and the projected linear size with a coevolution model of hot spots and a
cocoon. We take account of the deceleration effect by the cocoon head growth.
We find that the advance speed of hot spots and lobes inevitably show the
deceleration phase (CSO-MSO phase) and the acceleration phase (MSO-FRII phase).
This is ascribed to the change of the power-law index of ambient density
profile in the MSO phase ($\sim $1 kpc). It is also found that the cocoon shape
becomes nearly spherical or disrupted for MSOs, while an elongated morphology
is predicted for CSOs and FRIIs. This seems to be consistent with the higher
fraction of distorted morphology of MSOs than that of CSOs and FRI.
  Finally, we predict that only CSOs whose initial advance speed is higher than
about 0.1c can evolve into FRIIs, comparing the hot spot speed with the sound
speed of the ambient medium.


title:
Features of two-pion Bose-Einstein correlations based on event-by-event
  analysis in smoothed particle hydrodynamics

abstract:
  We examine the space-time structure of the particle-emitting sources with
fluctuating initial conditions in smoothed particle hydrodynamics. The two-pion
correlation functions of single events for the sources exhibit event-by-event
fluctuations. The large event-by-event fluctuations and wide distributions of
the error-inverse-weighted fluctuations between the HBT correlation functions
of single and mixed events are important features for the sources with the
fluctuating initial conditions. The root-mean-square of the weighted
fluctuations is a signal to detect the inhomogeneity of the systems produced in
high energy heavy ion collisions.


title: Intelligent tit-for-tat in the iterated prisoner's dilemma game

abstract:
  We seek a route to the equilibrium where all the agents cooperate in the
iterated prisoner's dilemma game on a two-dimensional plane, focusing on the
role of tit-for-tat strategy. When a time horizon, within which a strategy can
recall the past, is one time step, an equilibrium can be achieved as
cooperating strategies dominate the whole population via proliferation of
tit-for-tat. Extending the time horizon, we filter out poor strategies by
simplified replicator dynamics and observe a similar evolutionary pattern to
reach the cooperating equilibrium. In particular, the rise of a modified
tit-for-tat strategy plays a central role, which implies how a robust strategy
is adopted when provided with an enhanced memory capacity.


title: Origin and evolution of magnetars

abstract:
  We present a population synthesis study of the observed properties of the
magnetars, which allows for X-ray selection effects, investigating the
hypothesis that they are drawn from a population of progenitors that are more
massive than those of the normal radio pulsars. We assume that the anomalous
X-ray emission is caused by the decay of a toroidal or tangled up field that
does not partake in the spin down of the star.
  We find that we can explain the observed properties, such as the period and
field distributions and the Period - Period derivative diagram, if we suitably
parametrise the time evolution of the anomalous X-ray luminosity as an
exponentially decaying function of time.
  The magnetic flux of the neutron stars is required to be a strong function of
the progenitor mass with the magnetars arising from the mass range 20-45 solar
masses.
  Unlike with the radio pulsars, the magnetars only weakly constrain the birth
spin period, due to their rapid spin-down. Our model predicts a birthrate of
about 0.15-0.3 per century.


title:
Chaos synchronization of the master-slave generalized Lorenz systems via
  linear state error feedback control

abstract:
  This paper provides a unified method for analyzing chaos synchronization of
the generalized Lorenz systems. The considered synchronization scheme consists
of identical master and slave generalized Lorenz systems coupled by linear
state error variables. A sufficient synchronization criterion for a general
linear state error feedback controller is rigorously proven by means of
linearization and Lyapunov's direct methods. When a simple linear controller is
used in the scheme, some easily implemented algebraic synchronization
conditions are derived based on the upper and lower bounds of the master
chaotic system. These criteria are further optimized to improve their
sharpness. The optimized criteria are then applied to four typical generalized
Lorenz systems, i.e. the classical Lorenz system, the Chen system, the Lv
system and a unified chaotic system, obtaining precise corresponding
synchronization conditions. The advantages of the new criteria are revealed by
analytically and numerically comparing their sharpness with that of the known
criteria existing in the literature.


title:
On dual Schur domain decomposition method for linear first-order
  transient problems

abstract:
  This paper addresses some numerical and theoretical aspects of dual Schur
domain decomposition methods for linear first-order transient partial
differential equations. In this work, we consider the trapezoidal family of
schemes for integrating the ordinary differential equations (ODEs) for each
subdomain and present four different coupling methods, corresponding to
different algebraic constraints, for enforcing kinematic continuity on the
interface between the subdomains.
  Method 1 (d-continuity) is based on the conventional approach using
continuity of the primary variable and we show that this method is unstable for
a lot of commonly used time integrators including the mid-point rule. To
alleviate this difficulty, we propose a new Method 2 (Modified d-continuity)
and prove its stability for coupling all time integrators in the trapezoidal
family (except the forward Euler). Method 3 (v-continuity) is based on
enforcing the continuity of the time derivative of the primary variable.
However, this constraint introduces a drift in the primary variable on the
interface. We present Method 4 (Baumgarte stabilized) which uses Baumgarte
stabilization to limit this drift and we derive bounds for the stabilization
parameter to ensure stability.
  Our stability analysis is based on the ``energy'' method, and one of the main
contributions of this paper is the extension of the energy method (which was
previously introduced in the context of numerical methods for ODEs) to assess
the stability of numerical formulations for index-2 differential-algebraic
equations (DAEs).


title:
Dynamic Rupture, Fault Opening, and Near Fault Particle Motions along an
  Interface between Dissimilar Materials

abstract:
  Dynamic rupture propagation along an interface between two different elastic
solids under shear dominated loading is studied numerically by a 2-D lattice
particle model (LPM). The configuration of the lattice particle model consists
of two solid blocks of different elastic properties connected along a planar
interface. Each block is characterized as an isotropic elastic material and the
interface strength is described as a composite elastic modulus of a mismatch
function of the elastic properties of two dissimilar materials. The particle
interaction between the two blocks with pair inter-particle potential also
takes account of normal stress variations.


title: Generalized fractional Ornstein-Uhlenbeck processes

abstract:
  We introduce an extended version of the fractional Ornstein-Uhlenbeck (FOU)
process where the integrand is replaced by the exponential of an independent
L\'evy process. We call the process the generalized fractional
Ornstein-Uhlenbeck (GFOU) process. Alternatively, the process can be
constructed from a generalized Ornstein-Uhlenbeck (GOU) process using an
independent fractional Brownian motion (FBM) as integrator. We show that the
GFOU process is well-defined by checking the existence of the integral included
in the process, and investigate its properties. It is proved that the process
has a stationary version and exhibits long memory. We also find that the
process satisfies a certain stochastic differential equation. Our underlying
intention is to introduce long memory into the GOU process which has short
memory without losing the possibility of jumps. Note that both FOU and GOU
processes have found application in a variety of fields as useful alternatives
to the Ornstein-Uhlenbeck (OU) process.


title: Optoelectronic Sensitization of Carbon Nanotubes by CdTe Nanocrystals

abstract:
  We investigate the photoconductance of single-walled carbon
nanotube-nanocrystalhybrids. The nanocrystals are bound to the nanotubes via
molecular recognition. We find that the photoconductance of the hybrids can be
adjusted by the absorption characteristics of the nanocrystals. In addition,
the photoconductance of the hybrids surprisingly exhibits a slow time constant
of about 1 ms after excitation of the nanocrystals. The data are consistent
with a bolometrically induced current increase in the nanotubes caused by
photon absorption in the nanocrystals.


title: Capillary filling with randomly coated walls

abstract:
  The motion of an air-fluid interface through an irregularly coated capillary
is studied by analysing the Lucas-Washburn equation with a random capillary
force. The pinning probability goes from zero to a maximum value, as the
interface slows down. Under a critical velocity, the distribution of waiting
times $\tau$ displays a power-law tail $\sim \tau^{-2}$ which corresponds to a
strongly intermittent dynamics, also observed in experiments. We elaborate a
procedure to predict quantities of experimental interest, such as the average
interface trajectory and the distribution of pinning lengths.


title: Triangular clustering in document networks

abstract:
  Document networks are characteristic in that a document node, e.g. a webpage
or an article, carries meaningful content. Properties of document networks are
not only affected by topological connectivity between nodes, but also strongly
influenced by the semantic relation between content of the nodes. We observe
that document networks have a large number of triangles and a high value of
clustering coefficient. And there is a strong correlation between the
probability of formation of a triangle and the content similarity among the
three nodes involved. We propose the degree-similarity product (DSP) model
which well reproduces these properties. The model achieves this by using a
preferential attachment mechanism which favours the linkage between nodes that
are both popular and similar. This work is a step forward towards a better
understanding of the structure and evolution of document networks.


title:
Separability of the massive Dirac's equation in 5-dimensional
  Myers-Perry black hole geometry and its relation to a rank-three Killing-Yano
  tensor

abstract:
  The Dirac equation for the electron around a five-dimensional rotating black
hole with two different angular momenta is separated into purely radial and
purely angular equations. The general solution is expressed as a superposition
of solutions derived from these two decoupled ordinary differential equations.
By separating variables for the massive Klein-Gordon equation in the same
space-time background, I derive a simple and elegant form for the
Stackel-Killing tensor, which can be easily written as the square of a
rank-three Killing-Yano tensor. I have also explicitly constructed a symmetry
operator that commutes with the scalar Laplacian by using the Stackel-Killing
tensor, and the one with the Dirac operator by the Killing-Yano tensor admitted
by the five-dimensional Myers-Perry metric, respectively.

categories: hep-th astro-ph gr-qc hep-ph math-ph math.MP quant-ph


title:
Optical absorption of divalent metal tungstates: Correlation between the
  band-gap energy and the cation ionic radius

abstract:
  We have carried out optical-absorption and reflectance measurements at room
temperature in single crystals of AWO4 tungstates (A = Ba, Ca, Cd, Cu, Pb, Sr,
and Zn). From the experimental results their band-gap energy has been
determined to be 5.26 eV (BaWO4), 5.08 eV (SrWO4), 4.94 eV (CaWO4), 4.15 eV
(CdWO4), 3.9-4.4 eV (ZnWO4), 3.8-4.2 eV (PbWO4), and 2.3 eV (CuWO4). The
results are discussed in terms of the electronic structure of the studied
tungstates. It has been found that those compounds where only the s electron
states of the A2+ cation hybridize with the O 2p and W 5d states (e.g BaWO4)
have larger band-gap energies than those where also p, d, and f states of the
A2+ cation contribute to the top of the valence band and the bottom of the
conduction band (e.g. PbWO4). The results are of importance in view of the
large discrepancies existent in prevoiusly published data.


title:
Transport through a quantum dot subject to spin and charge bias: Kondo
  regime

abstract:
  Spin and charge transport through a quantum dot coupled to external
nonmagnetic leads is analyzed theoretically in terms of the non-equilibrium
Green function formalism based on the equation of motion method. The dot is
assumed to be subject to spin and charge bias, and the considerations are
focused on the Kondo effect in spin and charge transport. It is shown that the
differential spin conductance as a function of spin bias reveals a typical
zero-bias Kondo anomaly which becomes split when either magnetic field or
charge bias are applied. Significantly different behavior is found for mixed
charge/spin conductance. The influence of electron-phonon coupling in the dot
on tunneling current as well as on both spin and charge conductance is also
analyzed.


title: S-matrix and Quantum Tunneling in Gravitational Collapse

abstract:
  Using the recently introduced ACV reduced-action approach to transplanckian
scattering of light particles, we show that the $S$-matrix in the region of
classical gravitational collapse is related to a tunneling amplitude in an
effective field space. We understand in this way the role of both real and
complex field solutions, the choice of the physical ones, the absorption of the
elastic channel associated to inelastic multigraviton production and the
occurrence of extra absorption below the critical impact parameter. We are also
able to compute a class of quantum corrections to the original semiclassical
$S$-matrix that we argue to be qualitatively sensible and which, generally
speaking, tend to smooth out the semiclassical results.


title:
The large sieve, monodromy and zeta functions of algebraic curves, II:
  independence of the zeros

abstract:
  Using the sieve for Frobenius, we show that, in a certain sense, the roots of
the L-functions of "most" algebraic curves over finite fields do not satisfy
any non-trivial (linear or multiplicative) rational dependency relations. This
can be seen as an analogue of conjectures of linear independence among
ordinates of zeros of L-functions over number fields. As a corollary, we find,
for "most" pairs of distinct algebraic curves over a finite field, the limiting
distribution of the (suitably normalized) difference between the number of
rational points over extensions of the ground field. The method of proof also
emphasizes the relevance of Random Matrix models for this type of arithmetic
questions. We also describe an alternative approach, which relies on Serre's
theory of Frobenius tori, and we give a number of examples.


title: Thermal AGN Signatures in Blazars

abstract:
  Long ignored in blazars because of the dominance of the beamed radiation from
the jet, the topic of thermal emissions in these objects is just beginning to
be explored. While this emission is weak in most blazars compared to the
dominant nonthermal jet components, there is a growing body of evidence that
suggests that thermal emission is observable even in the most highly beamed
objects. The emitting regions, which can include the accretion disk as well as
the torus, are key parts of the central engine which also powers the jets. They
also may be of critical importance in helping us decide between unified scheme
models. We will review the observational evidence for thermal emissions in
blazars, with an emphasis on recent work, and the spectral and variability
characteristics that have been observed. The majority of the evidence for
thermal emission in blazars (now observed in several objects) has come as a
result of multiwavelength campaigns, where the object showed a clear bump in
the optical-UV in a faint state. However, evidence exists from other avenues as
well, including both purely spectral and variability based arguments as well as
statistical analyses of large samples of objects. We will also discuss the
impact of thermal emission on an object's overall SED, including its
Comptonized signatures. Finally, we will assess the current standing of unified
scheme models as respects thermal signatures and the prospects for detecting
thermal emission with new telescopes and missions, and further utilizing it as
a probe of the central engine of blazars.


title: Derandomizing the Lovasz Local Lemma more effectively

abstract:
  The famous Lovasz Local Lemma [EL75] is a powerful tool to non-constructively
prove the existence of combinatorial objects meeting a prescribed collection of
criteria. Kratochvil et al. applied this technique to prove that a k-CNF in
which each variable appears at most 2^k/(ek) times is always satisfiable
[KST93]. In a breakthrough paper, Beck found that if we lower the occurrences
to O(2^(k/48)/k), then a deterministic polynomial-time algorithm can find a
satisfying assignment to such an instance [Bec91]. Alon randomized the
algorithm and required O(2^(k/8)/k) occurrences [Alo91]. In [Mos06], we
exhibited a refinement of his method which copes with O(2^(k/6)/k) of them. The
hitherto best known randomized algorithm is due to Srinivasan and is capable of
solving O(2^(k/4)/k) occurrence instances [Sri08]. Answering two questions
asked by Srinivasan, we shall now present an approach that tolerates
O(2^(k/2)/k) occurrences per variable and which can most easily be
derandomized. The new algorithm bases on an alternative type of witness tree
structure and drops a number of limiting aspects common to all previous
methods.


title: D2 or M2? A Note on Membrane Scattering

abstract:
  Motivated by a physical interpretation of its correlation functions as
membrane scattering amplitudes, we re-address whether the Lorentzian BLG theory
can be quantized such that it preserves SO(8) superconformal symmetry. We find
that this appears to be possible. While the model seems to adequately reproduce
protected quantities such as chiral primary amplitudes and the four derivative
effective action, we conclude that, as understood at present, it gives a
relatively unpractical parametrization of the IR dynamics of M2-branes.


title:
An Adaptive Entanglement Distillation Scheme Using Quantum Low Density
  Parity Check Codes

abstract:
  Quantum low density parity check (QLDPC) codes are useful primitives for
quantum information processing because they can be encoded and decoded
efficiently. Besides, the error correcting capability of a few QLDPC codes
exceeds the quantum Gilbert-Varshamov bound. Here, we report a numerical
performance analysis of an adaptive entanglement distillation scheme using
QLDPC codes. In particular, we find that the expected yield of our adaptive
distillation scheme to combat depolarization errors exceed that of Leung and
Shor whenever the error probability is less than about 0.07 or greater than
about 0.28. This finding illustrates the effectiveness of using QLDPC codes in
entanglement distillation.


title:
The Irregular Set for Maps with the Specification Property has Full
  Topological Pressure

abstract:
  Let $(X,d)$ be a compact metric space, $f:X \mapsto X$ be a continuous map
with the specification property, and $\varphi: X \mapsto \IR$ a continuous
function. We consider the set of points for which the Birkhoff average of
$\varphi$ does not exist (which we call the irregular set for $\varphi$) and
show that this set is either empty or carries full topological pressure (in the
sense of Pesin and Pitskel). We formulate various equivalent natural conditions
on $\varphi$ that completely describe when the latter situation holds and give
examples of interesting systems to which our results apply but were not
previously known. As an application, we show that for a suspension flow over a
continuous map with specification, the irregular set carries full topological
entropy.


title:
An Information-Based Framework for Asset Pricing: X-Factor Theory and
  its Applications

abstract:
  A new framework for asset pricing based on modelling the information
available to market participants is presented. Each asset is characterised by
the cash flows it generates. Each cash flow is expressed as a function of one
or more independent random variables called market factors or "X-factors". Each
X-factor is associated with a "market information process", the values of which
become available to market participants. In addition to true information about
the X-factor, the information process contains an independent "noise" term
modelled here by a Brownian bridge. The information process thus gives partial
information about the X-factor, and the value of the market factor is only
revealed at the termination of the process. The market filtration is assumed to
be generated by the information processes associated with the X-factors. The
price of an asset is given by the risk-neutral expectation of the sum of the
discounted cash flows, conditional on the information available from the
filtration. The theory is developed in some detail, with a variety of
applications to credit risk management, share prices, interest rates, and
inflation. A number of new exactly solvable models are obtained for the price
processes of various types of assets and derivative securities; and a novel
mechanism is proposed to account for the dynamics of stochastic volatility and
dynamic correlation. A discrete-time version of the information-based framework
is also developed, and is used to construct a new class of models for the real
and nominal interest rate term structures, and the dynamics of the associated
price index.


title: A Thermodynamic Definition of Topological Pressure for Non-Compact Sets

abstract:
  We give a new definition of topological pressure for arbitrary (non-compact,
non-invariant) Borel subsets of metric spaces. This new quantity is defined via
a suitable variational principle, leading to an alternative definition of an
equilibrium state. We study the properties of this new quantity and compare it
with existing notions of topological pressure. We are particularly interested
in the situation when the ambient metric space is assumed to be compact. We
motivate the naturality of our definition by applying it to some interesting
examples, including the level sets of the pointwise Lyapunov exponent for the
Manneville-Pomeau family of maps.


title: On the role of the final state interactions in rare B-decays

abstract:
  The effects of final state interactions (FSI) in hadronic B-decays are
investigated. The model for FSI, based on Regge phenomenology of high-energy
hadronic interactions is proposed. It is shown that this model explains the
pattern of phases in matrix elements of $B\to\pi\pi$ and $B\to\rho\rho$ decays.
These phases play an important role for CP-violation in B-decays. The most
precise determination of the unitarity triangle angle $\alpha$ from $B_d\to
\rho\pi$ decays is performed. The relation between CP-asymmetries in $B\to
K\pi$ decays is discussed. It is emphasized that the large distance FSI can
explain the structure of polarizations of the vector mesons in B-decays and
other puzzles like a very large branching ratio of the B-decay to
$\bar\Xi_c\Lambda_c$.


title:
Comultiplication rules for the double Schur functions and Cauchy
  identities

abstract:
  The double Schur functions form a distinguished basis of the ring
\Lambda(x||a) which is a multiparameter generalization of the ring of symmetric
functions \Lambda(x). The canonical comultiplication on \Lambda(x) is extended
to \Lambda(x||a) in a natural way so that the double power sums symmetric
functions are primitive elements. We calculate the dual Littlewood-Richardson
coefficients in two different ways thus providing comultiplication rules for
the double Schur functions. We also prove multiparameter analogues of the
Cauchy identity. A new family of Schur type functions plays the role of a dual
object in the identities. We describe some properties of these dual Schur
functions including a combinatorial presentation and an expansion formula in
terms of the ordinary Schur functions. The dual Littlewood-Richardson
coefficients provide a multiplication rule for the dual Schur functions.


title: Hyperspherical harmonics with arbitrary arguments

abstract:
  The derivation scheme for hyperspherical harmonics (HSH) with arbitrary
arguments is proposed. It is demonstrated that HSH can be presented as the
product of HSH corresponding to spaces with lower dimensionality multiplied by
the orthogonal (Jacobi or Gegenbauer) polynomial. The relation of HSH to
quantum few-body problems is discussed. The explicit expressions for
orthonormal HSH in spaces with dimensions from 2 to 6 are given. The important
particular cases of four- and six-dimensional spaces are analyzed in detail and
explicit expressions for HSH are given for several choices of hyperangles. In
the six-dimensional space, HSH representing the kinetic energy operator
corresponding to i) the three-body problem in physical space and ii) four-body
planar problem are derived.


title:
Spectral flow is the integral of one forms on the Banach manifold of
  self adjoint Fredholm operators

abstract:
  One may trace the idea that spectral flow should be given as the integral of
a one form back to the 1974 Vancouver ICM address of I.M. Singer. Our main
theorem gives analytic formulae for the spectral flow along a norm
differentiable path of self-adjoint bounded Breuer-Fredholm operators in a
semi-finite von Neumann algebra. These formulae have a geometric interpretation
which derives from the proof. Namely we define a family of Banach submanifolds
of all bounded self-adjoint Breuer-Fredholm operators and on each submanifold
define global one forms whose integral on a norm differentiable path contained
in the submanifold calculates the spectral flow along this path. We emphasise
that our methods do not give a single globally defined one form on the self
adjoint Breuer- Fredholms whose integral along all paths is spectral flow
rather, as the choice of the plural `forms' in the title suggests, we need a
family of such one forms in order to confirm Singer's idea. The original
context for this result concerned paths of unbounded self-adjoint Fredholm
operators. We therefore prove analogous formulae for spectral flow in the
unbounded case as well. The proof is a synthesis of key contributions by
previous authors, whom we acknowledge in detail in the introduction, combined
with an additional important recent advance in the differential calculus of
functions of non-commuting operators.


title:
Direct observation of the e3ffect of isotope-induced disorder on the
  exciton binding energy in LiHxD1-x mixed crystals

abstract:
  The results of a quantitative study of the renormalization of the binding
energy of the Wannier-Mott exciton by the isotope effect are presented.


title: The Hamiltonian Analysis for Yang-Mills Theory on $R\times S^2$

abstract:
  Pure Yang-Mills theory on ${\mathbb R} \times S^2$ is analyzed in a
gauge-invariant Hamiltonian formalism. Using a suitable coordinatization for
the sphere and a gauge-invariant matrix parametrization for the gauge
potentials, we develop the Hamiltonian formalism in a manner that closely
parallels previous analysis on ${\mathbb R}^3$. The volume measure on the
physical configuration space of the gauge theory, the nonperturbative mass-gap
and the leading term of the vacuum wave functional are discussed using a
point-splitting regularization. All the results carry over smoothly to known
results on ${\mathbb R}^3$ in the limit in which the sphere is de-compactified
to a plane.


title: Different PDF approximations useful for LO Monte Carlo generators

abstract:
  The goal of this study is to find a prescription for defining parton
distributions (PDFs) which are most appropriate for use in those codes where
only LO matrix elements (MEs) are used, as in many Monte Carlo generators. We
describe a modification of LO PDFs, based on using alpha_S at NLO, a specific
prescription of the coupling in the QCD evolution, and violation of the
momentum sum rule. We compare results with the truth - the prediction using NLO
for both MEs and PDFs, and the standard LO prediction, finding that the
modified PDFs generally produce the best results.


title: Jet-jet and hadron-jet correlations in hadro- and electro-production

abstract:
  We discuss, in the framework of perturbative QCD at next to leading order,
two related observables which are usually considered to provide tests of the
BFKL dynamics : jet-jet correlations at Tevatron energies and forward
particle-jet correlations at HERA. In the first case we study the rapidity gap
dependence of the azimuthal correlations and find slightly too strong
correlations at large gap. In the second case we discuss the cross section as
well as the azimuthal correlations over a rapidity gap range of 5 units. We
find that the requirement of a forward particle imposes strong kinematical
constraints which distort the distributions, notably at small rapidity gaps. We
also show that the decorrelation is stronger in electroproduction than in
hadron-hadron collisions. Unfortunately no data are yet available for
comparison.


title:
Scalar-pseudoscalar meson behavior and restoration of symmetries in
  SU(3) PNJL model

abstract:
  The modification of mesonic observables in a hot medium is analyzed as a tool
to investigate the restoration of chiral and axial symmetries in the context of
the Polyakov-loop extended Nambu--Jona-Lasinio model. The results of the
extended model lead to the conclusion that the effects of the Polyakov loop are
fundamental for reproducing lattice findings. In particular, the partial
restoration of the chiral symmetry is faster in the PNJL model than in the NJL
one, and it is responsible for several effects: the meson-quark coupling
constants show a remarkable difference in both models, there is a faster
tendency to recover the Okubo-Zweig-Iizuka rule, and finally the topological
susceptibility nicely reproduces the lattice results around $T/T_c\approx 1.0$.


title: Light Charged Higgs and Lepton Universality in W boson Decays

abstract:
  We study the effect of a light charged Higgs appearing in supersymmetric
models containing two Higgs doublets on the measurement of leptonic branching
ratios of the W boson at LEP. We show that the $2.8 \sigma$ excess of the
branching ratio $W \to \tau \nu$ with respect to the other leptons correlates
well with the existence of charged Higgs with mass close to the mass of the W
boson which dominantly decays into $W^\star$ and a light CP odd Higgs boson $A$
with mass below $2m_b$, so that it decays into $\tau^+ \tau^-$ and $c \bar c$.
There are no searches for the charged Higgs in this channel and thus it could
be discovered in LEP data or at the Tevatron where it would be frequently
produced in top quark decays.


title:
Bandwidth-Controlled Insulator-Metal Transition and Correlated Metallic
  State in 5$d$ Transition Metal Oxides Sr$_{n+1}$Ir$_{n}$O$_{3n+1}$ ($n$=1, 2,
  and $\infty$)

abstract:
  We investigated the electronic structures of the 5$d$ Ruddlesden-Popper
series Sr$_{n+1}$Ir$_{n}$O$_{3n+1}$ ($n$=1, 2, and $\infty$) using optical
spectroscopy and first-principles calculations. As 5$d$ orbitals are spatially
more extended than 3$d$ or 4$d$ orbitals, it has been widely accepted that
correlation effects are minimal in 5$d$ compounds. However, we observed a
bandwidth-controlled transition from a Mott insulator to a metal as we
increased $n$. In addition, the artificially synthesized perovskite SrIrO$_{3}$
showed a very large mass enhancement of about 6, indicating that it was in a
correlated metallic state.


title:
Three-dimensional polyhedra can be described by three polynomial
  inequalities

abstract:
  Bosse et al. conjectured that for every natural number $d \ge 2$ and every
$d$-dimensional polytope $P$ in $\real^d$ there exist $d$ polynomials
$p_0(x),...,p_{d-1}(x)$ satisfying $P=\{x \in \mathbb{R}^d : p_0(x) \ge 0,
>..., p_{d-1}(x) \ge 0 \}.$ We show that for dimensions $d \le 3$ even every
$d$-dimensional polyhedron can be described by $d$ polynomial inequalities. The
proof of our result is constructive.


title: Materials with ZrCuSiAs Type Structure

abstract:
  The crystal chemistry and physical properties of materials with ZrCuSiAs type
structure is reviewed.


title: Scaler Mode Technique for the ARGO-YBJ Detector

abstract:
  The ARGO-YBJ experiment has been designed to study the Extensive Air Showers
with an energy threshold lower than that of the existing arrays by exploiting
the high altitude location(4300 m a.s.l. in Tibet, P.R. China) and the full
ground plane coverage. The lower energy limit of the detector (E $\sim$ 1 GeV)
is reached by the scaler mode technique, i.e. recording the counting rate at
fixed time intervals. At these energies, transient signals due to local (e.g.
Forbush Decreases) and cosmological (e.g. Gamma Ray Bursts) phenomena are
expected as a significant variation of the counting rate compared to the
background. In this paper the performance of the ARGO-YBJ detector operating in
scaler mode is described and discussed.


title: Tits indices over semilocal rings

abstract:
  We give a simplified proof of Tits' classification of semisimple algebraic
groups that remains valid over semilocal rings. In particular, we provide
explicit necessary and sufficient conditions that anisotropic groups of a given
type appear as anisotropic kernels of semisimple groups of a given Tits index.
We also give a new proof of the existence of all indices of exceptional inner
type using the notion of canonical dimension of projective homogeneous
varieties.


title: Precise measurement of the top quark mass from lepton+jets events at D0

abstract:
  We measure the mass of the top quark using top quark pair candidate events in
the lepton+jets channel from data corresponding to 1 fb-1 of integrated
luminosity collected by the D0 experiment at the Fermilab Tevatron collider. We
use a likelihood technique that reduces the jet energy scale uncertainty by
combining an in-situ jet energy calibration with the independent constraint on
the jet energy scale (JES) from the calibration derived using photon+jets and
dijet samples. We find the mass of the top quark to be
171.5+-1.8(stat.+JES)+-1.1(syst.) GeV.


title:
Electric-field induced spin excitations in two-dimensional spin-orbit
  coupled systems

abstract:
  Rigorous coupled spin-charge drift-diffusion equations are derived from
quantum-kinetic equations for the spin-density matrix that incorporate effects
due to k-linear spin-orbit interaction, an in-plane electric field, and the
elastic scattering on nonmagnetic impurities. The explicit analytical solution
for the induced magnetization exhibits a pole structure, from which the
dispersion relations of spin excitations are identified. Applications of the
general approach refer to the excitation of long-lived field-induced spin waves
by optically generated spin and charge patterns. This approach transfers
methods known in the physics of space-charge waves to the treatment of spin
eigenmodes. In addition, the amplification of an oscillating electric field by
spin injection is demonstrated.


title: Simulation of partial entanglement with one cbit and one M-box

abstract:
  We present a protocol to simulate the correlations implied by nonmaximally
entangled two qubit states. We extend this protocol to simulate the non-local
part of these correlations. These protocols use single cbit communication and a
single use of Millionaire box (M-box). To the best of our knowledge, these
resources are weaker than those used in previous protocols using classical
communication.


title: N=4 Chern-Simons theories with auxiliary vector multiplets

abstract:
  We investigate a class of quiver-type Chern-Simons gauge theories with some
Chern-Simons couplings vanishing. The vanishing of the couplings means that the
corresponding vector fields are auxiliary fields. We show that these theories
possess N=4 supersymmetry by writing down the actions and the supersymmetry
transformation in terms of component fields in manifestly Spin(4) covariant
form.


title:
Unlensing HST Observations of the Einstein Ring 1RXS J1131-1231: A
  Bayesian Analysis

abstract:
  We present a source and lens reconstruction for the optical Einstein ring
gravitational lens system RXS J1131-1231. We resolve detail in the source,
which is the host galaxy of a $z=0.658$ quasar, down to a resolution of 0.045
arc seconds (this is the size of the smallest conclusively resolved structures,
rather than the pixel scale), using a Bayesian technique with a realistic model
for the prior information. The source reconstruction reveals a substantial
amount of complex structure in the host galaxy, which is $\sim$ 8 kpc in extent
and contains several bright compact substructures, with the quasar source
residing in one of these bright substructures. Additionally, we recover the
mass distribution of the lensing galaxy, assuming a simply-parameterised model,
using information from both the quasar images and the extended images. This
allows a direct comparison of the amount of information about the lens that is
provided by the quasar images in comparison to the extended images. In this
system, we find that the extended images provide significantly more information
about the lens than the quasar images alone, especially if we do not include
prior constraints on the central position of the lens.


title:
On the connection between Hamilton and Lagrange formalism in Quantum
  Field Theory

abstract:
  The connection between the Hamilton and the standard Lagrange formalism is
established for a generic Quantum Field Theory with vanishing vacuum
expectation values of the fundamental fields. The Effective Actions in both
formalisms are the same if and only if the fundamental fields and the momentum
fields are related by the stationarity condition. These momentum fields in
general differ from the canonical fields as defined via the Effective Action.
By means of functional methods a systematic procedure is presented to identify
the full correlation functions, which depend on the momentum fields, as
functionals of those usually appearing in the standard Lagrange formalism.
Whereas Lagrange correlation functions can be decomposed into tree diagrams the
decomposition of Hamilton correlation functions involves loop corrections
similar to those arising in n-particle effective actions. To demonstrate the
method we derive for theories with linearized interactions the propagators of
composite auxiliary fields and the ones of the fundamental degrees of freedom.
The formalism is then utilized in the case of Coulomb gauge Yang-Mills theory
for which the relations between the two-point correlation functions of the
transversal and longitudinal components of the conjugate momentum to the ones
of the gauge field are given.


title: UHECR bounds on Lorentz violation in the photon sector

abstract:
  The aim of this brief review is to present a case study of how astrophysics
data can be used to get bounds on Lorentz-violating parameters. For this
purpose, a particularly simple Lorentz-violating modification of the Maxwell
theory of photons is considered, which maintains gauge invariance, CPT, and
renormalization. With a standard spin-one-half Dirac particle minimally coupled
to this nonstandard photon, the resulting modified-quantum-electrodynamics
model involves nineteen dimensionless "deformation parameters." Ten of these
parameters lead to birefringence and are already tightly constrained by
astrophysics. New bounds on the remaining nine nonbirefringent parameters have
been obtained from the inferred absence of vacuum Cherenkov radiation in
ultrahigh-energy-cosmic-ray (UHECR) events. The resulting astrophysics bounds
improve considerably upon current laboratory bounds and the implications of
this "null experiment" may be profound, both for elementary particle physics
and cosmology.


title: Heavy baryon properties with NLO accuracy in perturbative QCD

abstract:
  We present an analysis of the static properties of heavy baryons at
next-to-leading order in the perurbative expansion of QCD. We obtain analytical
next-to-leading order three-loop results for the two-point correlators of
baryonic currents with one finite mass quark field for a variety of quantum
numbers of the baryonic currents. We consider both the massless limit and the
HQET limit of the correlator as special cases of the general finite mass
formula and find agreement with previous results. We present closed form
expressions for the moments of the spectral density. We determine the residues
of physical baryon states using sum rule techniques.


title:
A Test for the Presence of a Signal, with Multiple Channels and Marked
  Poisson

abstract:
  We describe a statistical hypothesis test for the presence of a signal based
on the likelihood ratio statistic. We derive the test for a special case of
interest. We study extensions of the test to cases where there are multiple
channels and to marked Poisson distributions. We show the results of a number
of performance studies which indicate that the test works very well, even far
out in the tails of the distribution and with multiple channels and marked
Poisson.


title: Wilf conjecture

abstract:
  Let S(n,k) be the Stirling number of the second kind. Wilf conjectured that
the alternating sum of S(n,k) for k from 0 to n is not zero for all n>2. In
this paper, we prove that Wilf conjecture is true except at most one number
with the properties of weighted Motzkin number.


title: Non-associativity as gravity

abstract:
  Gravitation interactions are treated as non-associative part of the field's
interactions. Vector-potential of the Dirac equation is extended for the
octonionic algebra. The solution is considered as element of matrix set
$BS\times O_4$.


title: Isotope dependence of band-gap energy

abstract:
  The results of the quantitative investigations of the renormalization of the
absorption edge of different compounds by the isotope effect are described.


title:
Uniform-in-bandwidth consistency for kernel-type estimators of Shannon's
  entropy

abstract:
  We establish uniform-in-bandwidth consistency for kernel-type estimators of
the differential entropy. We consider two kernel-type estimators of Shannon's
entropy. As a consequence, an asymptotic 100% confidence interval of entropy is
provided.


title: Exact results of two-component Fermi gas in a hard wall trap

abstract:
  We investigate the ground state properties of a one-dimensional two-component
ultra-cold Fermi gas in an infinite potential well. Exact Bethe ansatz solution
is used to calculate the many-body wave function of the system. Then we
evaluate the single-particle reduced density matrix and two-particle density
density correlations of the system for different interaction strengths. We find
that the momentum density distributions of the strongly interacting
two-component Fermi gas is distinct from that of free spinless Fermi gas
although their position density distributions are similar. This interacting
system may be experimentally accessible using ultra-cold atoms.


title: Whittaker limits of difference spherical functions

abstract:
  We introduce the (global) q-Whittaker function as the limit at t=0 of the
q,t-spherical function extending the symmetric Macdonald polynomials to
arbitrary eigenvalues. The construction heavily depends on the technique of the
q-Gaussians developed by the author (and Stokman in the non-reduced case). In
this approach, the q-Whittaker function is given by a series convergent
everywhere, a kind of generating function for multi-dimensional q-Hermite
polynomials (closely related to the level 1 Demazure characters). One of the
applications is a q-version of the Shintani- Casselman- Shalika formula, which
appeared directly connected with q-Mehta- Macdonald identities in terms of the
Jackson integrals. This formula generalizes that of type A due to Gerasimov et
al. to arbitrary reduced root systems. At the end of the paper, we obtain a
q,t-counterpart of the Harish-Chandra asymptotic formula for the spherical
functions, including the Whittaker limit.


title: The nature of the soft X-ray source in DG Tau

abstract:
  The classical T Tauri star DG Tau shows all typical signatures of X-ray
activity and, in particular, harbors a resolved X-ray jet. We demonstrate that
its soft and hard X-ray components are separated spatially by approximately 0.2
arcsec by deriving the spatial offset between both components from the event
centroids of the soft and hard photons utilizing the intrinsic
energy-resolution of the Chandra ACIS-S detector. We also demonstrate that this
offset is physical and cannot be attributed to an instrumental origin or to low
counting statistics. Furthermore, the location of the derived soft X-ray
emission peak coincides with emission peaks observed for optical emission
lines, suggesting that both, soft X-rays and optical emission, have the same
physical origin.


title: New Results from the NEMO 3 Experiment

abstract:
  NEMO 3 is a currently running experiment to search for the neutrinoless
double beta decay and to study the two-neutrino double beta decay with 10kg of
enriched isotopes. On the basis of the first two years of data taking, a limit
on the neutrinoless decay $T_{1/2}^{0\nu} > 5.8\cdot10^{23}$ y at 90% CL was
obtained with $^{100}Mo$. The two-neutrino double beta decay half-lives were
measured for all seven $\beta\beta$ isotopes located in NEMO 3. New results are
obtained for two of these isotopes: $^{48}Ca T_{1/2}^{2\nu}=[4.4 ^{+0.5}_{-0.4}
(stat) \pm 0.4 (syst)]\cdot10^{19}$ y, $^{96}Zr T_{1/2}^{2\nu}=[2.3 \pm 0.2
(stat) \pm 0.3 (syst)]\cdot10^{19}$ y.


title: Universally-composable privacy amplification from causality constraints

abstract:
  We consider schemes for secret key distribution which use as a resource
correlations that violate Bell inequalities. We provide the first security
proof for such schemes, according to the strongest notion of security, the so
called universally-composable security. Our security proof does not rely on the
validity of quantum mechanics, it solely relies on the impossibility of
arbitrarily-fast signaling between separate physical systems. This allows for
secret communication in situations where the participants distrust their
quantum devices.


title: Scalar-tensor cosmologies: fixed points of the Jordan frame scalar field

abstract:
  We study the evolution of homogeneous and isotropic, flat cosmological models
within the general scalar-tensor theory of gravity with arbitrary coupling
function and potential. After introducing the limit of general relativity we
describe the details of the phase space geometry. Using the methods of
dynamical systems for the decoupled equation of the Jordan frame scalar field
we find the fixed points of flows in two cases: potential domination and matter
domination. We present the conditions on the mathematical form of the coupling
function and potential which determine the nature of the fixed points
(attractor or other). There are two types of fixed points, both are
characterized by cosmological evolution mimicking general relativity, but only
one of the types is compatible with the Solar System PPN constraints. The phase
space structure should also carry over to the Einstein frame as long as the
transformation between the frames is regular which however is not the case for
the latter (PPN compatible) fixed point.


title:
Homogenization of the Signorini boundary-value problem in a thick plane
  junction

abstract:
  We consider a mixed boundary-value problem for the Poisson equation in a
plane thick junction $\Omega_{\varepsilon}$ which is the union of a domain
$\Omega_0$ and a large number of $\varepsilon$-periodically situated thin rods.
The nonuniform Signorini conditions are given on the vertical sides of the thin
rods. The asymptotic analysis of this problem is made as $\varepsilon \to 0$,
i.e., when the number of the thin rods infinitely increases and their thickness
tends to zero. With the help of the integral identity method we prove the
convergence theorem and show that the nonuniform Signorini conditions are
transformed (as $\varepsilon \to 0$) in the limiting variational inequalities
in the region that is filled up by the thin rods in the limit passage. The
existence and uniqueness of the solution to this non-standard limit problem is
established. The convergence of the energy integrals is proved as well.


title: Classical tensors from quantum states

abstract:
  The embedding of a manifold M into a Hilbert-space H induces, via the
pull-back, a tensor field on M out of the Hermitian tensor on H. We propose a
general procedure to compute these tensors in particular for manifolds
admitting a Lie-group structure.


title: Consistency of a needlet spectral estimator on the sphere

abstract:
  The angular power spectrum of a stationary random field on the sphere is
estimated from the needlet coefficients of a single realization, observed with
increasingly fine resolution. The estimator we consider is similar to the one
recently used in practice by (Fa\"{y} et al. 2008) to estimate the power
spectrum of the Cosmic Microwave Background. The consistency of the estimator,
in the asymptotics of high frequencies, is proved for a model with a stationary
Gaussian field corrupted by heteroscedastic noise and missing data.


title: Spherical Averages on Regular and Semiregular Graphs

abstract:
  In 1966, P. Guenther proved the following result: Given a continuous function
f on a compact surface M of constant curvature -1 and its periodic lift g to
the universal covering, the hyperbolic plane, then the averages of the lift g
over increasing spheres converge to the average of the function f over the
surface M. In this article, we prove similar results for functions on the
vertices and edges of regular and semiregular graphs, with special emphasis on
the convergence rate. We also consider averages over more general sets like
arcs, tubes and horocycles.


title: Topological defects, fractals and the structure of quantum field theory

abstract:
  In this paper I discuss the formation of topological defects in quantum field
theory and the relation between fractals and coherent states. The study of
defect formation is particularly useful in the understanding of the same
mathematical structure of quantum field theory with particular reference to the
processes of non-equilibrium symmetry breaking. The functional realization of
fractals in terms of the q-deformed algebra of coherent states is also
presented. From one side, this sheds some light on the dynamical formation of
fractals. From the other side, it also exhibits the fractal nature of coherent
states, thus opening new perspectives in the analysis of those phenomena where
coherent states play a relevant role. The global nature of fractals appears to
emerge from local deformation processes and fractal properties are incorporated
in the framework of the theory of entire analytical functions.


title:
Momentum dependence of the energy gap in the superconducting state of
  optimally doped Bi2(Sr,R)2CuOy (R=La and Eu)

abstract:
  The energy gap of optimally doped Bi2(Sr,R)2CuOy (R=La and Eu) was probed by
angle resolved photoemission spectroscopy (ARPES) using a vacuum ultraviolet
laser (photon energy 6.994 eV) or He I resonance line (21.218 eV) as photon
source. The results show that the gap around the node at sufficiently low
temperatures can be well described by a monotonic d-wave gap function for both
samples and the gap of the R=La sample is larger reflecting the higher Tc.
However, an abrupt deviation from the d-wave gap function and an opposite R
dependence for the gap size were observed around the antinode, which represent
a clear disentanglement between the antinodal pseudogap and the nodal
superconducting gap.


title: Stanley depth of monomial ideals in three variables

abstract:
  We show that $\depth(S/I)=0$ if and only if $\sdepth(S/I)=0$, where $I\subset
S=K[x_1,...,x_n]$ is a monomial ideal. We give an algorithm to compute the
Stanley depth of $S/I$, where $I\subset S=K[x_1,x_2,x_3]$ is a monomial ideal.
Also, we prove that a monomial ideal $I\subset K[x_1,x_2,x_3]$ minimally
generated by three monomials has $\sdepth(I)=2$.


title:
Production of the Charmonium States chic_1 and chic_2 in Proton Nucleus
  Interactions at sqrt{s} = 41.6 GeV

abstract:
  A measurement of the ratio R_chic = (chic -> Jpsi + gam)/ Jpsi in pC, pTi and
pW interactions at 920 GeV/c (sqrt{s}=41.6 GeV) in the Feynman-x range -0.35 <
x_F(Jpsi) < 0.15 is presented. Both mu+mu- and e+e- Jpsi decay channels are
observed with an overall statistics of about 15000 chic events, which is by far
the largest available sample in pA collisions. The result is R_chic =
0.188+-0.013(st)(+0.024)(-0.022)(sys) averaged over the different materials,
when no Jpsi and chic polarisations are considered. The chic_1 to chic_2
production ratio R_12 = R_chic1/R_chic2 is measured to be 1.02+-0.40, leading
to a cross section ratio sigma(chic_1)/sigma(chic_2)=0.57+-0.23. The dependence
of R_chic on the Feynman-x of the Jpsi, x_F(Jpsi), and its transverse momentum,
p_T(Jpsi), is studied, as well as its dependence on the atomic number, A, of
the target. For the first time, an extensive study of possible biases on R_chic
and R_12 due to the dependence of acceptance on the polarization states of Jpsi
and chic is performed. By varying the polarisation parameter, lambda(obs), of
all produced Jpsi's by two sigma around the value measured by HERA-B, and
considering the maximum variation due to the possible chic_1 and chic_2
polarisations, it is shown that R_chic could change by a factor between 1.02
and 1.21 and R_12 by a factor between 0.89 and 1.16.


title:
Statistics of Microstructure Formation in Martensitic Transitions
  Studied by a Random-Field Potts Model with Dipolar-like Interactions

abstract:
  We have developed a simple model for the study of a cubic to tetragonal
martensitic transition, under athermal conditions, in systems with a certain
amount of disorder. We have performed numerical simulations that allow for a
statistical study of the dynamics of the transition when the system is driven
from the high-temperature cubic phase to the low-temperature degenerate
tetragonal phase. Our goal is to reveal the existence of kinetic constraints
that arise from competition between the equivalent variants of the martensitic
phase, and which prevent the system from reaching optimal final
microstructures.


title: The Normalized Ricci Flow on Four-Manifolds and Exotic Smooth Structures

abstract:
  In this article, we shall investigate the relationship between the existence
or non-existence of non-singular solutions to the normalized Ricci flow and
smooth structures on closed 4-manifolds, where non-singular solutions to the
normalized Ricci flow are solutions which exist for all time $t \in [0,
\infty)$ with uniformly bounded sectional curvature. In dimension 4, there
exist many compact topological manifolds admitting distinct smooth structures,
i.e., exotic smooth structures. Interestingly, in this article, the difference
between existence and non-existence of non-singular solutions to the normalized
Ricci flow on 4-manifolds turns out to strictly depend on the choice of smooth
structure. In fact, we shall prove that, for every natural number $\ell$, there
exists a compact topological 4-manifold $X_{\ell}$ which admits smooth
structures for which non-singular solutions of the normalized Ricci flow exist,
but also admits smooth structures for which no non-singular solution of the
normalized Ricci flow exists. Hence, in dimension 4, smooth structures become
definite obstructions to the existence of non-singular solutions to the
normalized Ricci flow.


title:
Observation of $B^{\pm} \to \psi(2S) \pi^{\pm}$ and search for direct
  CP-violation

abstract:
  We report the first observation of $B^{\pm}\to\psi(2S)\pi^{\pm}$, a Cabibbo-
and color-suppressed decay. This analysis is based on $657\times10^{6}$
$B\overline B$ events collected at the $\Upsilon(4S)$ resonance with the Belle
detector at the KEKB energy-asymmetric $e^+e^-$ collider. The measured
branching fraction is ($2.44 \pm 0.22 \pm 0.20$)$\times 10^{-5}$ and the charge
asymmetry is $\mathcal{A}=0.022 \pm 0.085 \pm 0.016$. The ratio of the
branching fractions $\mathcal {B}(B^{\pm} \to \psi(2S) \pi^{\pm})$$/ \mathcal
{B}(B^{\pm} \to \psi(2S) K^{\pm})$ $ = (3.99 \pm 0.36\pm 0.17)%$ is also
determined.


title:
Invariant indices of polarimetric purity. Generalized indices of purity
  for nxn covariance matrices

abstract:
  A proper set of indices characterizing the polarimetric purity of light and
material media is defined from the eigenvalues of the corresponding coherency
matrix. A simple and generalizable relation of these indices with the current
parameters characterizing the global purity is obtained. A general definition
for systems characterized by nxn positive semidefinite Hermitian matrices is
introduced in terms of the corresponding eigenvalues and diagonal Gell-Mann
matrices. The set of n-1 indices of purity has a nested structure and provide
complete information about the statistical purity of the system.


title: The Fundamentals of Generalized Electrodynamics

abstract:
  The article presents an alternative approach to the definition of vector
electrodynamic potential and its properties. It is shown that generally it has
vortical and potential components. The system of differential equations of
generalized electrodynamics (the macroscopical theory) is written down; and on
the basis of these equations the mechanism of occurrence of the electromagnetic
waves spreading in the direction of vector (longitudinal E-waves) is explained.
It is demonstrated that the new macroscopical theory is in accordance with
quantum electrodynamics. The author investigates the issue of physical
pithiness of longitudinal electromagnetic E-waves and specifies the references
to the experimental researches confirming the new theory.


title: Symmetry interaction and many-body correlations

abstract:
  It is shown how many-body correlations involving the symmetry potential
naturally arise in the molecular dynamics CoMD-II model. The effect of these
correlations on the collision dynamics at the Fermi energies is discussed.
Small level of correlations for systems of moderate asymmetry are able to
produce large effects also in simple observables like the charge distributions.
The comparison with predictions based on Equation Of State static calculations
is also discussed.


title:
A unified theoretical framework for fluctuating-charge models in
  atom-space and in bond-space

abstract:
  Our previously introduced QTPIE (charge transfer with polarization current
equilibration) model (J. Chen and T. J. Martinez, Chem. Phys. Lett. 438, 315
(2007)) is a fluctuating-charge model with correct asymptotic behavior. Unlike
most other fluctuating-charge models, QTPIE is formulated in terms of
charge-transfer variables and pairwise electronegativities, not atomic charge
variables and electronegativities. The pairwise character of the
electronegativities in QTPIE avoids spurious charge transfer when bonds are
broken. However, the increased number of variables leads to considerable
computational expense and a rank-deficient set of working equations, which is
numerically inconvenient. Here, we show that QTPIE can be exactly reformulated
in terms of atomic charge variables, leading to a considerable reduction in
computational complexity. The transformation between atomic and bond variables
is generally applicable to arbitrary fluctuating charge models, and uncovers an
underlying topological framework that can be used to understand the relation
between fluctuating-charge models and the classical theory of electrical
circuits.


title: Charm Physics at CDF

abstract: A survey of recent results in charm physics from CDF is presented.


title:
The SMC SNR 1E0102.2-7219 as a Calibration Standard for X-ray Astronomy
  in the 0.3-2.5 keV Bandpass

abstract:
  The flight calibration of the spectral response of CCD instruments below 1.5
keV is difficult in general because of the lack of strong lines in the on-board
calibration sources typically available. We have been using 1E 0102.2-7219, the
brightest supernova remnant in the Small Magellanic Cloud, to evaluate the
response models of the ACIS CCDs on the Chandra X-ray Observatory (CXO), the
EPIC CCDs on the XMM-Newton Observatory, the XIS CCDs on the Suzaku
Observatory, and the XRT CCD on the Swift Observatory. E0102 has strong lines
of O, Ne, and Mg below 1.5 keV and little or no Fe emission to complicate the
spectrum. The spectrum of E0102 has been well characterized using
high-resolution grating instruments, namely the XMM-Newton RGS and the CXO
HETG, through which a consistent spectral model has been developed that can
then be used to fit the lower-resolution CCD spectra. We have also used the
measured intensities of the lines to investigate the consistency of the
effective area models for the various instruments around the bright O (~570 eV
and 654 eV) and Ne (~910 eV and 1022 eV) lines. We find that the measured
fluxes of the O VII triplet, the O VIII Ly-alpha line, the Ne IX triplet, and
the Ne X Ly-alpha line generally agree to within +/-10 % for all instruments,
with 28 of our 32 fitted normalizations within +/-10% of the RGS-determined
value. The maximum discrepancies, computed as the percentage difference between
the lowest and highest normalization for any instrument pair, are 23% for the O
VII triplet, 24% for the O VIII Ly-alpha line, 13% for the Ne IX triplet, and
19% for the Ne X Ly-alpha line. If only the CXO and XMM are compared, the
maximum discrepancies are 22% for the O VII triplet, 16% for the O VIII
Ly-alpha line, 4% for the Ne IX triplet, and 12% for the Ne X Ly-alpha line.


title: Magnetic and thermal properties of a one-dimensional spin-1 model

abstract:
  We study the one-dimensional S=1 Blume-Emery-Griffiths model. Upon
transforming the spin model into an equivalent fermionic model, we provide the
exact solution within the Green's function and equations of motion formalism.
We show that the relevant response functions as well as thermodynamic
quantities can be determined, in the whole parameters space, in terms of a
finite set of local correlators. Furthermore, considering the case of an
antiferromagnetic chain with single-ion anisotropy in the presence of an
external magnetic field, we find three plateaus in the magnetization curve; in
the neighborhood of the endpoints of the intermediate plateau, the specific
heat shows a double peak structure.


title: Ranking Unit Squares with Few Visibilities

abstract:
  Given a set of n unit squares in the plane, the goal is to rank them in space
in such a way that only few squares see each other vertically. We prove that
ranking the squares according to the lexicographic order of their centers
results in at most 3n-7 pairwise visibilities for n at least 4. We also show
that this bound is best possible, by exhibiting a set of n squares with at
least 3n-7 pairwise visibilities under any ranking.


title: Exact Massive Solutions of Classical Massless Field Theories

abstract:
  We give the exact solution of classical equation of motion of a quartic
scalar massless field theory showing that this is massive and is represented by
a superposition of free particle solutions with a discrete spectrum. Then we
show that this is also a solution of the classical Yang-Mills field theory that
is so proved acquiring mass by dynamical evolution with a corresponding
discrete mass spectrum. Finally we develop quantum field theory starting with
this solution.


title:
Canonical tilting modules over shod algebras are regular in codimension
  one

abstract:
  We show that for a class of modules over shod algebras, including the
canonical tilting modules, the closures of the corresponding orbits in module
varieties are regular in codimension one.


title: Single-Field Inflation After WMAP5

abstract:
  Single-field models of inflation are analysed in light of the WMAP five-year
data. Assuming instantaneous reheating, we find that modular/new inflation
models with small powers in the effective inflaton self-interaction are more
strongly constrained than previously. The model with a cubic power lies outside
the 2 sigma regime when the number of e-folds is less than 60. We also find
that the predictions for the intermediate model of inflation do not overlap the
1 sigma region regardless of the power of the monomial potential. We analyse a
number of ultra-violet, DBI braneworld scenarios involving both wrapped and
multiple-brane configurations, where the inflaton kinetic energy is close to
the maximum allowed by the warped geometry. In all cases, we find that the
parameters of the warped throat are strongly constrained by observations.


title:
Stability Theory and the Foundations of Physics: A Challenge to Real
  Analysis and Numerical Calculation

abstract:
  At present, there exists no physically plausible example of a quantum field
theory for which the existence of solutions has been proven mathematically. The
Clay Mathematics Institute has offered a prize for proving existence for a
class of Yang-Mills theories defined by Jaffe and Witten. This paper proposes a
multi-stage strategy for proving existence for a quantum version of the
"'tHooft Polyakov" (tP) field theory, and argues that this theory, while not
renormalizable or physically plausible as it stands, opens up a clear path to a
physically plausible well-defined theory. The key initial challenge is to first
prove stability for a classical version of this theory, in the spirit of Walter
Strauss. The stability results of Bogomolnyi for classical PDE systems are
widely cited as a foundation of string theory, but they leave key questions
unaddressed, and may even call for small modifications of the tP model itself.
This paper calls attention to the questions which require more attention, and
proposes some partial possible answers. It also specifies a new numerical
method to check for stability for the usual "hedgehog" types of solution, a
method which may have broader potential uses for any ODE problems where
accuracy in derivatives is as important as accuracy in function values.


title: Probing the Upper Limit of Nonclassical Rotational Inertia

abstract:
  We study the effect of confinement on solid 4-He's nonclassical rotational
inertia (NCRI) in a torsional oscillator by constraining it to narrow annular
cells of various widths. The NCRI exhibits a broad maximum value of 20% for
annuli of approximately 100 micrometer width. Samples constrained to porous
media or to larger geometries both have smaller NCRI, mostly below about 1%. In
addition, we extend Kim and Chan's blocked annulus experiment to solid samples
with large supersolid fractions. Blocking the annulus suppresses the
nonclassical decoupling from 17.1% below the limit of our detection of 0.8%.
This result demonstrates the nonlocal nature of the supersolid phenomena. At 20
mK, NCRI depends on velocity history showing a closed hysteresis loop in
different thin annular cells.


title: Schmidt games and Markov partitions

abstract:
  Let T be a C^2-expanding self-map of a compact, connected, smooth, Riemannian
manifold M. We correct a minor gap in the proof of a theorem from the
literature: the set of points whose forward orbits are nondense has full
Hausdorff dimension. Our correction allows us to strengthen the theorem.
Combining the correction with Schmidt games, we generalize the theorem in
dimension one: given a point x in M, the set of points whose forward orbit
closures miss x is a winning set.


title: Splittings of monomial ideals

abstract:
  We provide some new conditions under which the graded Betti numbers of a
monomial ideal can be computed in terms of the graded Betti numbers of smaller
ideals, thus complementing Eliahou and Kervaire's splitting approach. As
applications, we show that edge ideals of graphs are splittable, and we provide
an iterative method for computing the Betti numbers of the cover ideals of
Cohen-Macaulay bipartite graphs. Finally, we consider the frequency with which
one can find particular splittings of monomial ideals and raise questions about
ideals whose resolutions are characteristic-dependent.


title: Triply special relativity from six dimensions

abstract:
  We show that the generalization of Doubly Special Relativity to a curved de
Sitter background can be obtained starting from a six-dimensional spacetime on
which quadratic constraints on position and momentum coordinates are imposed.


title:
Green's function for the Hodge Laplacian on some classes of Riemannian
  and Lorentzian symmetric spaces

abstract:
  We compute the Green's function for the Hodge Laplacian on the symmetric
spaces M\times\Sigma, where M is a simply connected n-dimensional Riemannian or
Lorentzian manifold of constant curvature and \Sigma is a simply connected
Riemannian surface of constant curvature. Our approach is based on a
generalization to the case of differential forms of the method of spherical
means and on the use of Riesz distributions on manifolds. The radial part of
the Green's function is governed by a fourth order analogue of the Heun
equation.


title: Calorimeter R&D for the SuperNEMO Double Beta Decay Experiment

abstract:
  SuperNEMO is a next-generation double beta decay experiment based on the
successful tracking plus calorimetry design approach of the NEMO3 experiment
currently running in the Laboratoire Souterrain de Modane (LSM). SuperNEMO can
study a range of isotopes, the baseline isotopes are 82Se and possibly 150Nd.
The total isotope mass will be 100-200 kg. A sensitivity to neutrinoless double
beta decay half-life greater than 10e26 years can be reached which gives access
to Majorana neutrino masses of 50-100 meV. One of the main challenges of the
SuperNEMO R&D is the development of the calorimeter with an unprecedented
energy resolution of 4% FWHM at 3 MeV (Qbb value of 82Se).


title: Sivers Asymmetry for the proton and the neutron

abstract:
  A formalism is presented to evaluate the Sivers function in constituent quark
models. A non-relativistic reduction of the scheme is performed and applied to
the Isgur-Karl model. The results obtained are consistent with a sizable Sivers
effect and the signs for the u and d flavor contributions turn out to be
opposite. The Burkardt Sum Rule is fulfilled to a large extent. After the
estimate of the QCD evolution of the results from the momentum scale of the
model to the experimental one, a reasonable agreement with the available data
is obtained. A calculation of nuclear effects in the extraction of neutron
single spin asymmetries in semi-inclusive deep inelastic scattering off 3He is
also described. In the kinematics of forth-coming experiments at JLab, it is
found that the nuclear effects arising within an Impulse Approximation approach
are under control.


title: Generalized uncertainty principles

abstract:
  The phenomenon in the essence of classical uncertainty principles is well
known since the thirties of the last century. We introduce a new phenomenon
which is in the essence of a new notion that we introduce: "Generalized
Uncertainty Principles". We show the relation between classical uncertainty
principles and generalized uncertainty principles. We generalized
"Landau-Pollak-Slepian" uncertainty principle. Our generalization relates the
following two quantities and two scaling parameters: 1) The weighted time
spreading $\int_{-\infty}^\infty |f(x)|^2w_1(x)dx$, ($w_1(x)$ is a non-negative
function). 2) The weighted frequency spreading $\int_{-\infty}^\infty
|\hat{f}(\omega)|^2w_2(\omega)d\omega$. 3) The time weight scale $a$,
${w_1}_a(x)=w_1(xa^{-1})$ and 4) The frequency weight scale $b$,
${w_2}_b(\omega)=w_2(\omega b^{-1})$. "Generalized Uncertainty Principle" is an
inequality that summarizes the constraints on the relations between the two
spreading quantities and two scaling parameters. For any two reasonable weights
$w_1(x)$ and $w_2(\omega)$, we introduced a three dimensional set in $R^3$ that
is in the essence of many uncertainty principles. The set is called
"possibility body". We showed that classical uncertainty principles (such as
the Heiseneberg-Pauli-Weyl uncertainty principle) stem from lower bounds for
different functions defined on the possibility body. We investigated
qualitative properties of general uncertainty principles and possibility
bodies. Using this approach we derived new (quantitative) uncertainty
principles for Landau-Pollak-Slepian weights. We found the general uncertainty
principles related to homogeneous weights, $w_1(x)=w_2(x)=x^k$, $k\in N$, up to
a constant.


title: Quiver representations in toric geometry

abstract:
  This article is based on my lecture notes from summer schools at the
Universities of Utah (June 2007) and Warwick (September 2007). We provide an
introduction to explicit methods in the study of moduli spaces of quiver
representations and derived categories arising in toric geometry. The first
main goal is to present the noncommutative geometric approach to semiprojective
toric varieties via quivers. To achieve this, we use geometric invariant theory
to construct both semiprojective toric varieties and moduli spaces of quiver
representations. The second main goal builds on the first by presenting an
introduction to explicit methods in derived categories of coherent sheaves in
toric geometry. We recall the notion of tilting bundles with examples, and
describe the McKay correspondence as a derived equivalence in some detail
following Bridgeland, King and Reid. We also describe extensions of their
result beyond the $G$-Hilbert scheme to other fine moduli spaces of bound
quiver representations.


title: Windings of planar random walks and averaged Dehn function

abstract:
  We prove a sharp estimate on the expected value of the integral of the index
of a simple random walk on the square or triangular lattice. This gives new
lower bounds on the averaged Dehn function, which measures the expected area
needed to fill a random curve with a disc.


title:
Well-posedness for the generalized Benjamin-Ono equations with arbitrary
  large initial data in the critical space

abstract:
  We prove that the generalized Benjamin-Ono equations
$\partial_tu+\mathcal{H}\partial_x^2u\pm u^k\partial_xu=0$, $k\geq 4$ are
locally well-posed in the scaling invariant spaces $\dot{H}^{s_k}(\R)$ where
$s_k=1/2-1/k$. Our results also hold in the non-homogeneous spaces
$H^{s_k}(\R)$. In the case $k=3$, local well-posedness is obtained in
$H^{s}(\R)$, $s>1/3$.


title:
Internal structure of a quantum soliton and classical excitations due to
  trap opening

abstract:
  We analytically solve two problems that may be useful in the context of the
recent observation of matter wave bright solitons in a one-dimensional
attractive atomic Bose gas. The first problem is strictly beyond mean field:
  From the Bethe ansatz solution we extract the internal correlation function
of the particle positions in the quantum soliton, that is for a fixed center of
mass position. The second problem is solved in the limit of a large number of
particles, where the mean field theory is asymptotically correct: It deals with
the number of excitations created by the opening of the trap, starting from a
pure soliton in a weakly curved harmonic potential.


title: On the vanishing of the Rokhlin invariant

abstract:
  It is a natural consequence of fundamental properties of the Casson invariant
that the Rokhlin invariant of an amphichiral integral homology 3-sphere M
vanishes. In this paper, we give a new direct proof of this vanishing property.
For such an M, we construct a manifold pair (Y,Q) of dimensions 6 and 3
equipped with some additional structure (6-dimensional spin e-manifold), such
that Q = M \cup M \cup (-M) and (Y,Q) \cong (-Y,-Q). We prove that (Y,Q) bounds
a 7-dimensional spin e-manifold (Z,X) by studying the cobordism group of
6-dimensional spin e-manifolds and the Z/2-actions on the two--point
configuration space of M minus one point. For any such (Z,X), the signature of
X vanishes, and this implies the vanishing of the Rokhlin invariant. The idea
of the construction of (Y,Q) comes from the definition of the
Kontsevich-Kuperberg-Thurston invariant for rational homology 3-spheres.


title:
Regularity of the optimal shape for the first eigenvalue of the
  Laplacian with volume and inclusion constraints

abstract:
  We consider the well-known following shape optimization problem:
$$\lambda_1(\Omega^*)=\min_{\stackrel{|\Omega|=a} {\Omega\subset{D}}}
\lambda_1(\Omega), $$ where $\lambda_1$ denotes the first eigenvalue of the
Laplace operator with homogeneous Dirichlet boundary condition, and $D$ is an
open bounded set (a box). It is well-known that the solution of this problem is
the ball of volume $a$ if such a ball exists in the box $D$ (Faber-Krahn's
theorem). In this paper, we prove regularity properties of the boundary of the
optimal shapes $\Omega^*$ in any case and in any dimension. Full regularity is
obtained in dimension 2.


title: 2-D constrained Navier-Stokes equation and intermediate asymptotics

abstract:
  We introduce a modified version of the two-dimensional Navier-Stokes
equation, preserving energy and momentum of inertia, which is motivated by the
occurrence of different dissipation time scales and related to the gradient
flow structure of the 2-D Navier-Stokes equation. The hope is to understand
intermediate asymptotics. The analysis we present here is purely formal. A
rigorous study of this equation will be done in a forthcoming paper.


title: Note on the Deodhar decomposition of a double Schubert cell

abstract:
  We show that for an algebraic reductive group $G$, the partition of a double
Schubert cell in the flag variety $G/B$ defined by Deodhar, and coming from a
Bialynicki-Birula decomposition, is not a stratification in general. We give a
counterexample for a group of type B$_n$, where the closure of some specific
cell of dimension $2n$ has a non-trivial intersection with a cell of dimension
$3n-3$


title: Twistor structures, tt*-geometry and singularity theory

abstract:
  We give an overview on the tt*-geometry defined for isolated hypersurface
singularities and tame functions via Brieskorn lattices. We discuss nilpotent
orbits in this context, as well as classifying spaces of Brieskorn lattices and
(limits of) period maps.


title: Differential forms on locally convex spaces and the Stokes formula

abstract:
  We prove a version of the Stokes formula for differential forms on locally
convex spaces. The main tool used for proving this formula is the surface layer
theorem proved in another paper by the author. Moreover, for differential forms
of a Sobolev-type class relative to a differentiable measure, we compute the
operator adjoint to the exterior differential in terms of standard operations
of calculus of differential forms and the logarithmic derivative. Previously,
this connection was established under essentially stronger assumptions.


title: Ft values of the T = 1/2 mirror beta transitions

abstract:
  A complete survey is presented of all half-life and branching-ratio
measurements related to the isospin T = 1/2 mirror beta transitions ranging
from 3He to 83Mo. No measurements are ignored, although some are rejected for
cause. Using the decay energies obtained in the 2003 Mass Evaluation
experimental ft values are then determined for the transitions up to 45V. For
the first time also all associated theoretical corrections needed to convert
these results into "corrected" Ft values, similar to the superallowed 0+ -> 0+
pure Fermi beta transitions, were calculated. Precisions of the resulting
values are in most cases between 0.1 % and 0.4 %. These Ft(mirror) values can
now be used to extract precise weak interaction information from past and
ongoing correlation measurements in the beta decay of the T = 1/2 mirror beta
transitions.


title:
Long-lived spin entanglement induced by a spatially correlated thermal
  bath

abstract:
  We investigate how two spatially separated qubits coupled to a common heat
bath can be entangled by purely dissipative dynamics. We identify a dynamical
time scale associated with the lifetime of the dissipatively generated
entanglement and show that it can be much longer than either the typical
single-qubit decoherence time or the time scale on which a direct exchange
interaction can entangle the qubits. We give an approximate analytical
expression for the long-time evolution of the qubit concurrence and propose an
ion trap scheme in which such dynamics should be observable.


title: On a constrained 2-D Navier-Stokes equation

abstract:
  The planar Navier-Stokes equation exhibits, in absence of external forces, a
trivial asymptotics in time. Nevertheless the appearence of coherent structures
suggests non-trivial intermediate asymptotics which should be explained in
terms of the equation itself. Motivated by the separation of the different time
scales observed in the dynamics of the Navier-Stokes equation, we study the
well-posedness and asymptotic behaviour of a constrained equation which
neglects the variation of the energy and moment of inertia.


title:
Measurement of the Inclusive Jet Cross Section at the Fermilab Tevatron
  p-pbar Collider Using a Cone-Based Jet Algorithm

abstract:
  We present a measurement of the inclusive jet cross section in p-pbar
collisions at sqrt{s}=1.96 TeV based on data collected by the CDF II detector
with an integrated luminosity of 1.13 fb^-1. The measurement was made using the
cone-based Midpoint jet clustering algorithm in the rapidity region of |y|<2.1.
The results are consistent with next-to-leading-order perturbative QCD
predictions based on recent parton distribution functions (PDFs), and are
expected to provide increased precision in PDFs at high parton momentum
fraction x. The results are also compared to the recent inclusive jet cross
section measurement using the k_T jet clustering algorithm, and we find that
the ratio of the cross sections measured with the two algorithms is in
agreement with theoretical expectations over a large range of jet transverse
momentum and rapidity.


title: An exact Ramsey principle for block sequences

abstract:
  We prove an exact, i.e., formulated without $\Delta$-expansions, Ramsey
principle for infinite block sequences in vector spaces over countable fields,
where the two sides of the dichotomic principle are represented by respectively
winning strategies in Gowers' block sequence game and winning strategies in the
infinite asymptotic game. This allows us to recover Gowers' dichotomy theorem
for block sequences in normed vector spaces by a simple application of the
basic determinacy theorem for infinite asymptotic games.


title: $n$-Subspaces in linear and unitary spaces

abstract:
  We study a relation between brick $n$-tuples of subspaces of a finite
dimensional linear space, and irreducible $n$-tuples of subspaces of a finite
dimensional Hilbert (unitary) space such that a linear combination, with
positive coefficients, of orthogonal projections onto these subspaces equals
the identity operator. We prove that brick systems of one-dimensional subspaces
and the systems obtained from them by applying the Coxeter functors (in
particular, all brick triples and quadruples of subspaces) can be unitarized.
For each brick triple and quadruple of subspaces, we describe sets of
characters that admit a unitarization.


title: On Sun's conjecture concerning disjoint cosets

abstract:
  In 2004, Zhi-Wei Sun posed the following conjecture: If a_1G_1,...,a_kG_k
(k>1) are finitely many pairwise disjoint left cosets in a group G with all the
indices [G:G_i] finite, then for some 1\le i<j\le k, the greatest common
divisor of [G:G_i] and [G:G_j] is at least k. In this paper, we confirm Sun's
conjecture for k=3,4.


title:
Large t diffractive J/\psi photoproduction with proton dissociation in
  ultraperipheral pA collisions at LHC

abstract:
  We evaluate the large momentum transfer $J/\psi$ photoproduction with
rapidity gaps in ultraperipheral proton-ion collisions at the LHC which
provides an effective method of probing dynamics of large t elastic hard QCD
Pomeron interactions. It is shown that the experimental studies of this process
would allow to investigate the energy dependence of cross section of elastic
scattering of a small $c\bar c$ dipole off the gluon over a wide range of
invariant energies 10^3 < s_{c\bar c - gluon} < 10^6 GeV^2. The accessible
energy range exceeds the one reached in \gamma p at HERA by a factor of 10 and
allows the kinematic cuts which improve greatly sensitivity to the Pomeron
dynamics as compared to the HERA measurements. The cross section is expected to
change by a factor \ge 20 throughout this interval and our estimates predict
quite reasonable counting rates for this process with the several of the LHC
detectors.