title: Gravitational Stability of Circumnuclear Disks in Elliptical Galaxies

abstract:
  A significant fraction of nearby elliptical galaxies are known to have high
density gas disks in their circumnuclear (CN) region (0.1 to a few kpc). Yet,
ellipticals, especially luminous ones, show little signs of recent star
formation (SF). To investigate the possible cause of the dearth of SF in these
systems, we study the gravitational stability of CN gas disks embedded within
the potentials of both the stellar bulge and the central massive black hole
(BH) in ellipticals. We find that CN disks in higher mass galaxies are
generally more stable than those in lower mass galaxies, because higher mass
galaxies tend to have more massive BHs and more centrally concentrated stellar
density profiles. We also consider the case in which the central stellar
density profile has a core, which is often observed for ellipticals whose total
stellar mass is higher than about 10^11 Msun. Such a cored stellar density
profile leads to more unstable CN disks than the power-law density profile
characteristic of less massive galaxies. However, the more massive BHs in
high-mass galaxies act to stabilize the CN disk. Our results demonstrate that
the gravitational potentials of both the central BH and the stellar component
should be taken into account when studying the properties of CN disks, as their
stability is sensitive to both the BH mass and the stellar density profile. Our
results could explain the observed trend that less luminous ellipticals have a
greater tendency to exhibit ongoing SF than giant ellipticals.


title: Evolution of Phase-Space Density in Dark Matter Halos

abstract:
  The evolution of the phase-space density profile in dark matter (DM) halos is
investigated by means of constrained simulations, designed to control the
merging history of a given DM halo. Halos evolve through a series of quiescent
phases of a slow accretion intermitted by violent events of major mergers. In
the quiescent phases the density of the halo closely follows the NFW profile
and the phase-space density profile, Q(r), is given by the Taylor & Navarro
power law, r^{-beta}, where beta ~ 1.9 and stays remarkably stable over the
Hubble time. Expressing the phase-space density by the NFW parameters, Q(r)=Qs
(r/Rs)^{-beta}, the evolution of Q is determined by Qs. We have found that the
effective mass surface density within Rs, Sigma_s = rhos Rs, remains constant
throughout the evolution of a given DM halo along the main branch of its
merging tree. This invariance entails that Qs ~ Rs^{-5/2} and Q(r) ~
Sigma_s^{-1/2} Rs^{-5/2} (r/ Rs)^{-beta}. It follows that the phase-space
density remains constant, in the sense of Qs=const., in the quiescent phases
and it decreases as Rs^{-5/2} in the violent ones. The physical origin of the
NFW density profile and the phase-space density power law is still unknown.
Yet, the numerical experiments show that halos recover these relations after
the violent phases. The major mergers drive Rs to increase and Qs to decrease
discontinuously while keeping Qs Rs^{5/2} = const. The virial equilibrium in
the quiescent phases implies that a DM halos evolves along a sequence of NFW
profiles with constant energy per unit volume (i.e., pressure) within Rs.


title: Higgs boson from the meta-stable SUSY breaking sector

abstract:
  We construct a calculable model of electroweak symmetry breaking in which the
Higgs doublet emerges from the meta-stable SUSY breaking sector as a pseudo
Nambu-Goldstone boson. The Higgs boson mass is further protected by the little
Higgs mechanism, and naturally suppressed by a two-loop factor from the SUSY
breaking scale of 10 TeV. Gaugino and sfermion masses arise from standard gauge
mediation, but the Higgsino obtains a tree-level mass at the SUSY breaking
scale. At 1 TeV, aside from new gauge bosons and fermions similar to other
little Higgs models and their superpartners, our model predicts additional
electroweak triplets and doublets from the SUSY breaking sector.


title: Boltzmann and the art of flying

abstract:
  One of the less known facets of Ludwig Boltzmann was that of an advocate of
Aviation, one of the most challenging technological problems of his times.
Boltzmann followed closely the studies of pioneers like Otto Lilienthal in
Berlin, and during a lecture on a prestigious conference he vehemently defended
further investments in the area. In this article I discuss his involvement with
Aviation, his role in its development and his correspondence with two flight
pioneers, Otto Lilienthal e Wilhelm Kress.


title: Exponents of 2-multiarrangements and multiplicity lattices

abstract:
  We introduce a concept of multiplicity lattices of 2-multiarrangements,
determine the combinatorics and geometry of that lattice, and give a criterion
and method to construct a basis for derivation modules effectively.


title: A Canonical High Energy Afterglow Emission Light Curve?

abstract:
  We present self consistent calculations of Synchrotron self Compton (SSC)
radiation that takes place within the afterglow blast wave and External inverse
Compton (EIC) radiation that takes place when flare photons (produced by an
internal process) pass through the blast wave. We show that if our current
interpretations of the Swift XRT data are correct, there should be a canonical
high energy afterglow emission light curve. We expect that GRBs with a long
term X-ray flattening or X-ray flares should show similar high energy features.
The EIC emission, however, is long lasting and weak and might be outshined by
the SSC emission of the forward shock. The high energy emission could be well
detected by the soon to be launched GLAST satellite. Its detection could shed
new light on the conditions within the emitting regions of GRBs.


title: Time delayed processes in physics, biophysics and archaeology

abstract:
  The motion of particles, where the particles: electrons, ions in microtubules
or migrated peoples can be described as the superposition of diffusion and
ordered waves. In this paper it is shown that the master equation for transport
processes can be formulated as the time delayed hyperbolic partial equation.
The equation describes the processes with memory. For characteristic times
shorter than the relaxation time the master equation is the generalized Klein -
Gordon equation.
  Key words: hyperbolic transport, microtubules, heat waves, Neolithic
migration


title:
Observed flux density enhancement at submillimeter wavelengths during an
  X-class flare

abstract:
  We analyse the 30 October, 2004, X1.2/SF solar event that occurred in AR
10691 (N13 W18) at around 11:44 UT. Observations at 212 and 405 GHz of the
Solar Submillimeter Telescope (SST), with high time resolution (5 ms), show an
intense impulsive burst followed by a long-lasting thermal phase. EUV images
from the Extreme Ultraviolet Imaging Telescope (SOHO/EIT) are used to identify
the possible emitting sources. Data from the Radio Solar Telescope Network
(RSTN) complement our spectral observations below 15 GHz. During the impulsive
phase the turnover frequency is above 15.4 GHz. The long-lasting phase is
analysed in terms of thermal emission and compared with GOES observations. From
the ratio between the two GOES soft X-ray bands, we derive the temperature and
emission measure, which is used to estimate the free-free submillimeter flux
density. Good temporal agreement is found between the estimated and observed
profiles, however the former is larger than the latter.


title:
Theory of capillary-induced interactions beyond the superposition
  approximation

abstract:
  Within a general theoretical framework we study the effective,
deformation-induced interaction between two colloidal particles trapped at a
fluid interface in the regime of small deformations. In many studies, this
interaction has been computed with the ansatz that the actual interface
configuration for the pair is given by the linear superposition of the
interface deformations around the single particles. Here we assess the validity
of this approach and compute the leading term of the effective interaction for
large interparticle separation beyond this so-called superposition
approximation. As an application, we consider the experimentally relevant case
of interface deformations owing to the electrostatic field emanating from
charged colloidal particles. In mechanical isolation, i.e., if the net force
acting on the total system consisting of the particles plus the interface
vanishes, the superposition approximation is actually invalid. The effective
capillary interaction is governed by contributions beyond this approximation
and turns out to be attractive. For sufficiently small surface charges on the
colloids, such that linearization is strictly valid, and at asymptotically
large separations, the effective interaction does not overcome the direct
electrostatic repulsion between the colloidal particles.


title:
Towards an exact adaptive algorithm for the determinant of a rational
  matrix

abstract:
  In this paper we propose several strategies for the exact computation of the
determinant of a rational matrix. First, we use the Chinese Remaindering
Theorem and the rational reconstruction to recover the rational determinant
from its modular images. Then we show a preconditioning for the determinant
which allows us to skip the rational reconstruction process and reconstruct an
integer result. We compare those approaches with matrix preconditioning which
allow us to treat integer instead of rational matrices. This allows us to
introduce integer determinant algorithms to the rational determinant problem.
In particular, we discuss the applicability of the adaptive determinant
algorithm of [9] and compare it with the integer Chinese Remaindering scheme.
We present an analysis of the complexity of the strategies and evaluate their
experimental performance on numerous examples. This experience allows us to
develop an adaptive strategy which would choose the best solution at the run
time, depending on matrix properties. All strategies have been implemented in
LinBox linear algebra library.


title: Large-scale structure of time evolving citation networks

abstract:
  In this paper we examine a number of methods for probing and understanding
the large-scale structure of networks that evolve over time. We focus in
particular on citation networks, networks of references between documents such
as papers, patents, or court cases. We describe three different methods of
analysis, one based on an expectation-maximization algorithm, one based on
modularity optimization, and one based on eigenvector centrality. Using the
network of citations between opinions of the United States Supreme Court as an
example, we demonstrate how each of these methods can reveal significant
structural divisions in the network, and how, ultimately, the combination of
all three can help us develop a coherent overall picture of the network's
shape.


title: Superconductivity due to co-operative Kondo effect in Pu 115's

abstract:
  We outline key elements of a theory that accounts for anomalous properties of
the PuCoGa$_5$ and PuRhGa$_5$ compounds as a consequence of a two-body
interference between two Kondo screening channels. Virtual valence fluctuations
of the magnetic Pu configurations create two conduction channels of different
symmetry. Using the symplectic large-N approach, we are able to demonstrate our
pairing mechanism in an exactly solvable large-N limit. The critical
temperature reaches its maximum when the energy levels of excited valence
configurations are almost degenerate. The symmetry of the order parameter is
determined by the product of the Wannier form factors in the interfering
conduction channels.


title: Parton showers with quantum interference

abstract:
  We specify recursive equations that could be used to generate a lowest order
parton shower for hard scattering in hadron-hadron collisions. The formalism is
based on the factorization soft and collinear interactions from relatively
harder interactions in QCD amplitudes. It incorporates quantum interference
between different amplitudes in those cases in which the interference diagrams
have leading soft or collinear singularities. It incorporates the color and
spin information carried by partons emerging from a hard interaction. One
motivation for this work is to have a method that can naturally cooperate with
next-to-leading order calculations.


title: Local attachment in networks under churn

abstract:
  In this contribution we introduce local attachment as an universal
network-joining protocol for peer-to-peer networks, social networks, or other
kinds of networks. Based on this protocol nodes in a finite-size network
dynamically create power-law connectivity distributions. Nodes or peers
maintain them in a self-organized statistical way by incorporating local
information only. We investigate the structural and macroscopic properties of
such local attachment networks by extensive numerical simulations, including
correlations and scaling relations between exponents. The emergence of the
power-law degree distribution is further investigated by considering
preferential attachment with a nonlinear attractiveness function as an
approximative model for local attachment. This study suggests the local
attachment scheme as a procedure to be included in future peer-to-peer
protocols to enable the efficient production of stable network topologies in a
continuously changing environment.


title:
The discovery of two extremely low luminosity Milky Way globular
  clusters

abstract:
  We report the discovery of two extremely low luminosity globular clusters in
the Milky Way Halo. These objects were detected in the Sloan Digital Sky Survey
Data Release 5 and confirmed with deeper imaging at the Calar Alto Observatory.
The clusters, Koposov 1 and Koposov 2, are located at $\sim 40-50$ kpc and
appear to have old stellar populations and luminosities of only $M_V \sim -1$
mag. Their observed sizes of $\sim 3$ pc are well within the expected tidal
limit of $\sim$10 pc at that distance. Together with Palomar 1, AM 4 and
Whiting 1, these new clusters are the lowest luminosity globulars orbiting the
Milky Way, with Koposov 2 the most extreme. Koposov 1 appears to lie close to
distant branch of the Sagittarius stream. The half-mass relaxation times of
Koposov 1 and 2 are only $\sim 70$ and $\sim 55$ Myr respectively (2 orders of
magnitude shorter than the age of the stellar populations), so it would seem
that they have undergone drastic mass segregation. Since they do not appear to
be very concentrated, their evaporation timescales may be as low as $\sim 0.1
t_{\rm Hubble}$. These discoveries show that the structural parameter space of
globular clusters in the Milky Way halo is not yet fully explored. They also
add, through their short remaining survival times, significant direct evidence
for a once much larger population of globular clusters.


title: A 3-Stranded Quantum Algorithm for the Jones Polynomial

abstract:
  Let K be a 3-stranded knot (or link), and let L denote the number of
crossings in K. Let $\epsilon_{1}$ and $\epsilon_{2}$ be two positive real
numbers such that $\epsilon_{2}$ is less than or equal to 1.
  In this paper, we create two algorithms for computing the value of the Jones
polynomial of K at all points $t=exp(i\phi)$ of the unit circle in the complex
plane such that the absolute value of $\phi$ is less than or equal to $\pi/3$.
  The first algorithm, called the classical 3-stranded braid (3-SB) algorithm,
is a classical deterministic algorithm that has time complexity O(L). The
second, called the quantum 3-SB algorithm, is a quantum algorithm that computes
an estimate of the Jones polynomial of K at $exp(i\phi))$ within a precision of
$\epsilon_{1}$ with a probability of success bounded below by $1-\epsilon_{2}%.
The execution time complexity of this algorithm is O(nL), where n is the
ceiling function of (ln(4/\epsilon_{2}))/(2(\epsilon_{2})^2). The compilation
time complexity, i.e., an asymptotic measure of the amount of time to assemble
the hardware that executes the algorithm, is O(L).


title: Quantum Fields with Noncommutative Target Spaces

abstract:
  Quantum field theories (QFT's) on noncommutative spacetimes are currently
under intensive study. Usually such theories have world sheet noncommutativity.
In the present work, instead, we study QFT's with commutative world sheet and
noncommutative target space. Such noncommutativity can be interpreted in terms
of twisted statistics and is related to earlier work of Oeckl [1], and others
[2,3,4,5,6,7,8]. The twisted spectra of their free Hamiltonians has been found
earlier by Carmona et al [9,10]. We review their derivation and then compute
the partition function of one such typical theory. It leads to a deformed black
body spectrum, which is analysed in detail. The difference between the usual
and the deformed black body spectrum appears in the region of high frequencies.
Therefore we expect that the deformed black body radiation may potentially be
used to compute a GZK cut-off which will depend on the noncommutative parameter
$\theta$.


title: Modeling Computations in a Semantic Network

abstract:
  Semantic network research has seen a resurgence from its early history in the
cognitive sciences with the inception of the Semantic Web initiative. The
Semantic Web effort has brought forth an array of technologies that support the
encoding, storage, and querying of the semantic network data structure at the
world stage. Currently, the popular conception of the Semantic Web is that of a
data modeling medium where real and conceptual entities are related in
semantically meaningful ways. However, new models have emerged that explicitly
encode procedural information within the semantic network substrate. With these
new technologies, the Semantic Web has evolved from a data modeling medium to a
computational medium. This article provides a classification of existing
computational modeling efforts and the requirements of supporting technologies
that will aid in the further growth of this burgeoning domain.


title: The Cosmological Slingshot Scenario: Myths and Facts

abstract:
  We generalize the Cosmological Slingshot Scenario for a Slingshot brane
moving in a Klebanov-Strassler throat. We show that the horizon and isotropy
problems of standard cosmology are avoided, while the flatness problem is
acceptably alleviated. Regarding the primordial perturbations, we identify
their vacuum state and elucidate the evolution from the quantum to the
classical regimes. Also, we calculate their exact power spectrum showing its
compatibility with current data. We discuss the bouncing solution from a four
dimensional point of view. In this framework the radial and angular motion of
the Slingshot brane are described by two scalar fields. We show that the
bouncing solution for the scale factor in String frame is mapped into a
monotonically increasing (in conformal time) solution in the Einstein frame. We
finally discuss about the regularity of the geometry in Einstein frame.


title: Socioeconomic Networks with Long-Range Interactions

abstract:
  We study a modified version of a model previously proposed by Jackson and
Wolinsky to account for communicating information and allocating goods in
socioeconomic networks. In the model, the utility function of each node is
given by a weighted sum of contributions from all accessible nodes. The
weights, parameterized by the variable $\delta$, decrease with distance. We
introduce a growth mechanism where new nodes attach to the existing network
preferentially by utility. By increasing $\delta$, the network structure
evolves from a power-law to an exponential degree distribution, passing through
a regime characterised by shorter average path length, lower degree
assortativity and higher central point dominance. In the second part of the
paper we compare different network structures in terms of the average utility
received by each node. We show that power-law networks provide higher average
utility than Poisson random networks. This provides a possible justification
for the ubiquitousness of scale-free networks in the real world.


title:
Matching WMAP 3-yrs results with the Cosmological Slingshot Primordial
  Spectrum

abstract:
  We consider a recently proposed scenario for the generation of primordial
cosmological perturbations, the so called Cosmological Slingshot scenario. We
firstly obtain a general expression for the Slingshot primordial power spectrum
which extends previous results by including a blue pre-bounce residual
contribution at large scales. Starting from this expression we numerically
compute the CMB temperature and polarization power spectra arising from the
Slingshot scenario and show that they excellently match the standard WMAP
3-years best-fit results. In particular, if the residual blue spectrum is far
above the largest WMAP observed scale, the Slingshot primordial spectrum fits
the data well by only fixing its amplitude and spectral index at the pivot
scale k_p=10^{-3}h x Mpc^{-1}. We finally show that all possible distinctive
Slingshot signatures in the CMB power spectra are confined to very low
multipoles and thus very hard to detect due to large cosmic variance dominated
error bars at these scales.


title: Quantum criticality and the break-up of the Kondo pseudo-potential

abstract:
  We discuss how Anderson's ideas of nominal and real valence can be
incorporated into the current discussion of heavy electron quantum criticality.
In the heavy electron phase, the nominal valence of a screened magnetic ion
differs from its real valence by one unit. We identify this discrepancy with
the formation of a positively charged background we call the Kondo
pseudo-potential. At the quantum critical point, the sudden collapse of the
heavy electron Fermi surface can be identified with the return of the nominal
to the real valence. This leads to the interesting idea that the heavy electron
quantum critical point may involve locally critical charge degrees of freedom.
We discuss how this might come about within a large N Schwinger boson scheme.


title: Orbifold cup products and ring structures on Hochschild cohomologies

abstract:
  In this paper we study the Hochschild cohomology ring of convolution algebras
associated to orbifolds, as well as their deformation quantizations. In the
first case the ring structure is given in terms of a wedge product on twisted
polyvectorfields on the inertia orbifold. After deformation quantization, the
ring structure defines a product on the cohomology of the inertia orbifold. We
study the relation between this product and an $S^1$-equivariant version of the
Chen--Ruan product. In particular, we give a de Rham model for this equivariant
orbifold cohomology.


title:
Py-Calabi quasi-morphisms and quasi-states on orientable surfaces of
  higher genus

abstract:
  We show that Py-Calabi quasi-morphism on the group of Hamiltonian
diffeomorphisms of surfaces of higher genus gives rise to a quasi-state.


title:
Simple approach for high-contrast optical imaging and characterization
  of graphene-based sheets

abstract:
  A simple optical method is presented for identifying and measuring the
effective optical properties of nanometer-thick, graphene-based materials,
based on the use of substrates consisting of a thin dielectric layer on
silicon. High contrast between the graphene-based materials and the substrate
is obtained by choosing appropriate optical properties and thickness of the
dielectric layer. The effective refractive index and optical absorption
coefficient of graphene oxide, thermally reduced graphene oxide, and graphene
are obtained by comparing the predicted and measured contrasts.


title:
Similarity between the primary and secondary air-assisted liquid jet
  breakup mechanism

abstract:
  we report an ultrafast synchrotron x-ray phase contrast imaging study of the
primary breakup mechanism of a coaxial air-assisted water jet. We demonstrate
that there exist great similarities in the phenomenology of primary breakup
with that of the secondary breakup. Especially, a membrane-mediated breakup
mechanism dominates the breakup process for a wide range of air speeds. This
finding reveals the intrinsic connections of these two breakup regimes and has
deep implications on the unified theoretical approach in treating the breakup
mechanism of high speed liquid jet.


title: Natural SUSY Dark Matter: A Window on the GUT Scale

abstract:
  One of the key motivations for supersymmetry is that it provides a natural
candidate for dark matter. For a long time the density of this candidate
particle fell within cosmological bounds across much of the SUSY parameter
space. However with the precision results of WMAP, it has become apparent that
the majority of the SUSY parameter space no longer fits the observed relic
density. This has given rise to claims that supersymmetry no longer provides a
natural explanation of dark matter. We address this claim by quantifying the
degree of fine-tuning required for the different dark matter regions. We find
that the dark matter regions vary widely in the degree of tuning required. This
degree of tuning can then be used to provide valuable insights into the
structure of SUSY breaking at the GUT scale.


title:
Bifurcations and bistability in cavity assisted photoassociation of
  Bose-Einstein condensed molecules

abstract:
  We study the photo-association of Bose-Einstein condensed atoms into
molecules using an optical cavity field. The driven cavity field introduces a
new dynamical degree of freedom into the photoassociation process, whose role
in determining the stationary behavior has not previously been considered. The
semiclassical stationary solutions for the atom and molecules as well as the
intracavity field are found and their stability and scaling properties are
determined in terms of experimentally controllable parameters including driving
amplitude of the cavity and the nonlinear interactions between atoms and
molecules. For weak cavity driving, we find a bifurcation in the atom and
molecule number occurs that signals a transition from a stable steady state to
nonlinear Rabi oscillations. For a strongly driven cavity, there exists
bistability in the atom and molecule number.


title:
Improved constraints on dark energy from Chandra X-ray observations of
  the largest relaxed galaxy clusters

abstract:
  We present constraints on the mean matter density, Omega_m, dark energy
density, Omega_de, and the dark energy equation of state parameter, w, using
Chandra measurements of the X-ray gas mass fraction (fgas) in 42 hot (kT>5keV),
X-ray luminous, dynamically relaxed galaxy clusters spanning the redshift range
0.05<z<1.1. Using only the fgas data for the 6 lowest redshift clusters at
z<0.15, for which dark energy has a negligible effect on the measurements, we
measure Omega_m=0.28+-0.06 (68% confidence, using standard priors on the Hubble
Constant, H_0, and mean baryon density, Omega_bh^2). Analyzing the data for all
42 clusters, employing only weak priors on H_0 and Omega_bh^2, we obtain a
similar result on Omega_m and detect the effects of dark energy on the
distances to the clusters at ~99.99% confidence, with Omega_de=0.86+-0.21 for a
non-flat LCDM model. The detection of dark energy is comparable in significance
to recent SNIa studies and represents strong, independent evidence for cosmic
acceleration. Systematic scatter remains undetected in the fgas data, despite a
weighted mean statistical scatter in the distance measurements of only ~5%. For
a flat cosmology with constant w, we measure Omega_m=0.28+-0.06 and
w=-1.14+-0.31. Combining the fgas data with independent constraints from CMB
and SNIa studies removes the need for priors on Omega_bh^2 and H_0 and leads to
tighter constraints: Omega_m=0.253+-0.021 and w=-0.98+-0.07 for the same
constant-w model. More general analyses in which we relax the assumption of
flatness and/or allow evolution in w remain consistent with the cosmological
constant paradigm. Our analysis includes conservative allowances for systematic
uncertainties. The small systematic scatter and tight constraints bode well for
future dark energy studies using the fgas method. (Abridged)


title: Fabrication and Performance Tests of a Segmented P-Type HPGe Detector

abstract:
  A p-type HPGe detector has been segmented by cutting, with a diamond saw, and
etching six circumferential grooves through the Li-diffused dead layer. The
degree of segmentation was tested with the 88 keV gamma rays from a
well-collimated source of 109Cd. The fraction of events, recognized as
occurring in more than one segment, and rejected from the energy interval 2038
+/- 5 keV, was measured as 0.59.


title: Universality of Mixed Action Extrapolation Formulae

abstract:
  Mixed action theories with chirally symmetric valence fermions exhibit very
desirable features both at the level of the lattice calculations as well as in
the construction and implementation of the low energy mixed action effective
field theory. In this work we show that when such a mixed action effective
field theory is projected onto the valence sector, both the Lagrangian and the
extrapolation formulae become universal in form through next to leading order,
for all variants of discretization methods used for the sea fermions. Our
conclusion relies on the chiral nature of the valence quarks. The result
implies that for all sea quark methods which are in the same universality class
as QCD, the numerical values of the physical coefficients in the various mixed
action chiral Lagrangians will be the same up to lattice spacing dependent
corrections. This allows us to construct a prescription to determine the mixed
action extrapolation formulae for a large class of hadronic correlation
functions computed in partially quenched chiral perturbation theory at the
one-loop level. For specific examples, we apply this prescription to the
nucleon twist--2 matrix elements and the nucleon--nucleon system. In addition,
we determine the mixed action extrapolation formula for the neutron EDM as this
provides a nice example of a theta-dependent observable; these observables are
exceptions to our prescription.


title: A twisted FZZ-like dual for the two-dimensional black hole

abstract:
  We review and study the duality between string theory formulated on a curved
exact background (the two dimensional black hole) and string theory in flat
space with a tachyon-like potential. We generalize previous results in this
subject by discussing a twisted version of the
Fateev-Zamolodchikov-Zamolodchikov conjecture. This duality is shown to hold at
the level of N-point correlation functions on the sphere topology, and connects
tree-level string amplitudes in the Euclidean version of the 2D black hole (x
time) to correlation functions in a non-linear sigma-model in flat space but in
presence of a tachyon wall potential and a linear dilaton. The dual CFT
corresponds to the perturbed 2D quantum gravity coupled to c<1 matter (x time),
where the operator that describes the tachyon-like potential can be seen as a
n=2 momentum mode perturbation, while the usual sine-Liouville operator would
correspond to the vortex sector n =1. We show how the sine-Liouville
interaction term arises through a twisting of the marginal deformation
introduced here, and discuss such 'twisting' as a non-trivial realization of
the symmetries of the theory. After briefly reviewing the computation of
correlation functions in sine-Liouville CFT, we give a precise prescription for
computing correlation functions in the twisted model. To show the new version
of the correspondence we make use of a formula recently proven by S. Ribault
and J. Teschner, which connects the correlation functions in the
Wess-Zumino-Witten theory to correlation functions in the Liouville theory.
Conversely, the duality discussed here can be thought of as a free field
realization of such remarkable formula.


title: Evidence for single top quark production at D0

abstract:
  The results of the first analysis to show evidence for production of single
top quarks are presented. Using 0.9 fb-1 of data collected with the D0 detector
at the Fermilab Tevatron, the analysis is performed in the electron+jets and
muon+jets decay modes, taking special care in modeling the large backgrounds,
applying a new powerful b-quark tagging algorithm and using three multivariate
techniques to extract the small signal in the data. The combined measured
production cross section is 4.8 +- 1.3 pb. The probability to measure a cross
section at this value or higher in the absence of a signal is 0.027%,
corresponding to a 3.5 standard deviation significance.


title: Weak amenability and 2-weak amenability of Beurling algebras

abstract:
  Let $L^1_\om(G)$ be a Beurling algebra on a locally compact abelian group
$G$. We look for general conditions on the weight which allows the vanishing of
continuous derivations of $L^1_\om(G)$. This leads us to introducing
vector-valued Beurling algebras and considering the translation of operators on
them. This is then used to connect the augmentation ideal to the behavior of
derivation space. We apply these results to give examples of various classes of
Beurling algebras which are weakly amenable, 2-weakly amenable or fail to be
even 2-weakly amenable.


title:
First Results from the XENON10 Dark Matter Experiment at the Gran Sasso
  National Laboratory

abstract:
  The XENON10 experiment at the Gran Sasso National Laboratory uses a 15 kg
xenon dual phase time projection chamber (XeTPC) to search for dark matter
weakly interacting massive particles (WIMPs). The detector measures
simultaneously the scintillation and the ionization produced by radiation in
pure liquid xenon, to discriminate signal from background down to 4.5 keV
nuclear recoil energy. A blind analysis of 58.6 live days of data, acquired
between October 6, 2006 and February 14, 2007, and using a fiducial mass of 5.4
kg, excludes previously unexplored parameter space, setting a new 90% C.L.
upper limit for the WIMP-nucleon spin-independent cross-section of 8.8 x
10^{-44} cm^2 for a WIMP mass of 100 GeV/c^2, and 4.5 x 10^{-44} cm^2 for a
WIMP mass of 30 GeV/c^2. This result further constrains predictions of
supersymmetric models.


title: Braided Sweedler cohomology

abstract:
  We introduced a braided Sweedler cohomology, which is adequate to work with
the H-braided cleft extensions studied in [J. A. Guccione and J. J. Guccione,
Theory of braided Hopf crossed products, Journal of Algebra, Vol 261 (2003)
54-101]


title: On cosmological constant in Causal Set theory

abstract:
  Resolution of the cosmological constant problem based on Causal Set theory is
discussed. It is argued that one should not observe any spacetime variations in
cosmological constant if Causal Set approach is correct.


title:
Meta-Stable Brane Configurations by Adding an Orientifold-Plane to
  Giveon-Kutasov

abstract:
  In hep-th/0703135, they have found the type IIA intersecting brane
configuration where there exist three NS5-branes, D4-branes and anti-D4-branes.
By analyzing the gravitational interaction for the D4-branes in the background
of the NS5-branes, the phase structures in different regions of the parameter
space were studied in the context of classical string theory. In this paper, by
adding the orientifold 4-plane and 6-plane to the above brane configuration, we
describe the intersecting brane configurations of type IIA string theory
corresponding to the meta-stable nonsupersymmetric vacua of these gauge
theories.


title:
A perturbation theory for large deviation functionals in fluctuating
  hydrodynamics

abstract:
  We study a large deviation functional of density fluctuation by analyzing
stochastic non-linear diffusion equations driven by the difference between the
densities fixed at the boundaries. By using a fundamental equality that yields
the fluctuation theorem, we first relate the large deviation functional with a
minimization problem. We then develop a perturbation method for solving the
problem. In particular, by performing an expansion with respect to the average
current, we derive the lowest order expression for the deviation from the local
equilibrium part. This expression implies that the deviation is written as the
space-time integration of the excess entropy production rate during the most
probable process of generating the fluctuation that corresponds to the argument
of the large deviation functional.


title: Phase Transition of XY Model in Heptagonal Lattice

abstract:
  We numerically investigate the nature of the phase transition of the XY model
in the heptagonal lattice with the negative curvature, in comparison to other
interaction structures such as a flat two-dimensional (2D) square lattice and a
small-world network. Although the heptagonal lattice has a very short
characteristic path length like the small-world network structure, it is
revealed via calculation of the Binder's cumulant that the former exhibits a
zero-temperature phase transition while the latter has the finite-temperature
transition of the mean-field nature. Through the computation of the vortex
density as well as the correlation function in the low-temperature
approximation, we show that the absence of the phase transition originates from
the strong spinwave-type fluctuation, which is discussed in relation to the
usual 2D XY model.


title:
AKARI observations of circumstellar dust in the globular clusters NGC104
  and NGC362

abstract:
  We report preliminary results of AKARI observations of two globular clusters,
NGC104 and NGC362. Imaging data covering areas of about 10x10 arcmin^2 centered
on the two clusters have been obtained with InfraRed Camera (IRC) at 2.4, 3.2,
4.1, 7.0, 9.0, 11.0, 15.0, 18.0 and 24.0 mu. We used F11/F2 and F24/F7 flux
ratios as diagnostics of circumstellar dust emission. Dust emissions are mainly
detected from variable stars obviously on the asymptotic giant branch, but some
variable stars that reside below the tip of the first-ascending giant branch
also show dust emissions. We found eight red sources with F24/F7 ratio greater
than unity in NGC362. Six out of the eight have no 2MASS counterparts. However,
we found no such source in NGC104.


title: Symmetry Partition Sort

abstract:
  In this paper, we propose a useful replacement for quicksort-style utility
functions. The replacement is called Symmetry Partition Sort, which has
essentially the same principle as Proportion Extend Sort. The maximal
difference between them is that the new algorithm always places already
partially sorted inputs (used as a basis for the proportional extension) on
both ends when entering the partition routine. This is advantageous to speeding
up the partition routine. The library function based on the new algorithm is
more attractive than Psort which is a library function introduced in 2004. Its
implementation mechanism is simple. The source code is clearer. The speed is
faster, with O(n log n) performance guarantee. Both the robustness and
adaptivity are better. As a library function, it is competitive.


title:
Conserved spin Hall conductance in two dimensional electron gas in a
  perpendicular magnetic field

abstract:
  Using the microscopic theory of the conserved spin current [Phys. Rev. Lett.
\textbf{96}, 076604 (2006)], we investigate the spin Hall effect in the two
dimensional electron gas system with a perpendicular magnetic field. The spin
Hall conductance $\sigma_{\mu\nu}^{s}$ as a response to the electric field
consists of two parts, i.e., the conventional part $\sigma_{\mu\nu}^{s0}$ and
the spin torque dipole correction $\sigma_{\mu\nu}^{s\tau}$. It is shown that
the spin-orbit coupling competes with Zeeman splitting by introducing
additional degeneracies between different Landau levels at certain values of
magnetic field. These degeneracies, if occurring at the Fermi level, turn to
give rise to resonances in both $\sigma_{\mu\nu}^{s0}$ and $\sigma_{\mu\nu
}^{s\tau}$ in spin Hall conductance. Remarkably, both of these two components
have the same sign in the wide range of variation in the magnetic field, which
result in an overall enhancement of the total spin Hall current. In particular,
the magnitude of $\sigma_{\mu\nu}^{s\tau}$ is much larger than that of
$\sigma_{\mu\nu}^{s0}$ around the resonance.


title: A Bayesian approach to strong lensing modelling of galaxy clusters

abstract:
  In this paper, we describe a procedure for modelling strong lensing galaxy
clusters with parametric methods, and to rank models quantitatively using the
Bayesian evidence. We use a publicly available Markov chain Monte-Carlo (MCMC)
sampler ('Bayesys'), allowing us to avoid local minima in the likelihood
functions. To illustrate the power of the MCMC technique, we simulate three
clusters of galaxies, each composed of a cluster-scale halo and a set of
perturbing galaxy-scale subhalos. We ray-trace three light beams through each
model to produce a catalogue of multiple images, and then use the MCMC sampler
to recover the model parameters in the three different lensing configurations.
We find that, for typical Hubble Space Telescope (HST)-quality imaging data,
the total mass in the Einstein radius is recovered with ~1-5% error according
to the considered lensing configuration. However, we find that the mass of the
galaxies is strongly degenerated with the cluster mass when no multiple images
appear in the cluster centre. The mass of the galaxies is generally recovered
with a 20% error, largely due to the poorly constrained cut-off radius.
Finally, we describe how to rank models quantitatively using the Bayesian
evidence. We confirm the ability of strong lensing to constrain the mass
profile in the central region of galaxy clusters in this way. Ultimately, such
a method applied to strong lensing clusters with a very large number of
multiple images may provide unique geometrical constraints on cosmology. The
implementation of the MCMC sampler used in this paper has been done within the
framework of the Lenstool software package, which is publicly available.


title: A filtered version of the bipolar theorem of Brannath and Schachermayer

abstract:
  We extend the Bipolar Theorem of Brannath and Schachermayer (1999) to the
space of nonnegative cadlag supermartingales on a filtered probability space.
We formulate the notion of fork-convexity as an analogue to convexity in this
setting. As an intermediate step in the proof of our main result we establish a
conditional version of the Bipolar theorem. In an application to mathematical
finance we describe the structure of the set of dual processes of the utility
maximization problem of Kramkov and Schachermayer (1999) and give a
budget-constraint characterization of admissible consumption processes in an
incomplete semimartingale market.


title:
Power-law Conductivity inside the Mott gap: application to
  $\kappa-(BEDT-TTF)_2Cu_2(CN)_3$

abstract:
  The charge dynamics of spin-liquid states described by U(1) gauge theory
coupling to fermionic spinons is discussed in this paper. We find that the
gapless spinons give rise to a power law optical conductivity inside the charge
gap. The theory is applied to explain the unusual optical conductivity observed
recently in the organic compound $\kappa-(BEDT-TTF)_2Cu_2(CN)_3$. We also
propose an optical experiment to search for the in-gap excitations in the
Kagome spin liquid insulator.


title:
Optimal consumption from investment and random endowment in incomplete
  semimartingale markets

abstract:
  We consider the problem of maximizing expected utility from consumption in a
constrained incomplete semimartingale market with a random endowment process,
and establish a general existence and uniqueness result using techniques from
convex duality. The notion of asymptotic elasticity of Kramkov and
Schachermayer is extended to the time-dependent case. By imposing no smoothness
requirements on the utility function in the temporal argument, we can treat
both pure consumption and combined consumption/terminal wealth problems, in a
common framework. To make the duality approach possible, we provide a detailed
characterization of the enlarged dual domain which is reminiscent of the
enlargement of $L^1$ to its topological bidual $(L^{\infty})^*$, a space of
finitely-additive measures. As an application, we treat the case of a
constrained It\^ o-process market-model.


title: Massive and Massless Neutrinos on Unbalanced Seesaws

abstract:
  The observation of neutrino oscillations requires new physics beyond the
standard model (SM). A SM-like gauge theory with p lepton families can be
extended by introducing q heavy right-handed Majorana neutrinos but preserving
its SU(2)_L x U(1)_Y gauge symmetry. The overall neutrino mass matrix M turns
out to be a symmetric (p+q) x (p+q) matrix. Given p>q, the rank of M is in
general equal to 2q, corresponding to 2q non-zero mass eigenvalues. The
existence of (p-q) massless left-handed Majorana neutrinos is an exact
consequence of the model, independent of the usual approximation made in
deriving the Type-I seesaw relation between the effective p x p light Majorana
neutrino mass matrix M_\nu and the q x q heavy Majorana neutrino mass matrix
M_R. In other words, the numbers of massive left- and right-handed neutrinos
are fairly matched. A good example to illustrate this seesaw fair play rule is
the minimal seesaw model with p=3 and q=2, in which one massless neutrino sits
on the unbalanced seesaw.


title: Puzzles in charm spectroscopy

abstract:
  We briefly analyze aspects of open and hidden charm resonances, discussing in
particular the mesons $D_{sJ}(2860)$ and X(3872).


title: Evidence for ablated flows in the shell of nova DQ Her

abstract:
  High-resolution longslit Halpha spectra of the shell of the old nova DQ Her
have been obtained with the William Herschel Telescope using the ISIS
spectrograph. An equatorial expansion velocity of 370+/-14 km/s is derived from
the spectra which, in conjunction with a narrowband Halpha image of the
remnant, allows a distance estimate of 525+/-28 pc. An equatorial ring which
exhibits enhanced [NII] emission has also been detected and the inclination
angle of the shell is found to be 86.8+/-0.2 degrees with respect to the line
of sight. The spectra also reveal tails extending from the clumps in the shell,
which have a radial velocity increasing along their length. This suggests the
presence of a stellar wind, collimated in the polar direction, which ablates
fragments of material from the clumps and accelerates them into its stream up
to a terminal velocity of order 800-900 km/s.


title: On the width of cold fronts in clusters of galaxies due to conduction

abstract:
  We consider the impact of thermal conduction in clusters of galaxies on the
(unmagnetized) interface between a cold gaseous cloud and a hotter gas flowing
over the cloud (the so-called cold front). We argue that near the stagnation
point of the flow conduction creates a spatially extended layer of constant
thickness $\Delta$, where $\Delta$ is of order $\sim\sqrt{kR/U}$, and $R$ is
the curvature radius of the cloud, $U$ is the velocity of the flow at infinity,
and $k$ is the conductivity of the gas. For typical parameters of the observed
fronts, one finds $\Delta \ll R$. The formation time of such a layer is $\sim
R/U$. Once the layer is formed, its thickness only slowly varies with time and
the quasi-steady layer may persist for many characteristic time scales. Based
on these simple arguments one can use the observed width of the cold fronts in
galaxy clusters to constrain the effective thermal conductivity of the
intra-cluster medium.


title: Anomalous Hall effect in a two-dimensional electron gas

abstract:
  The anomalous Hall effect in a magnetic two-dimensional electron gas with
Rashba spin-orbit coupling is studied within the Kubo-Streda formalism in the
presence of pointlike potential impurities. We find that all contributions to
the anomalous Hall conductivity vanish to leading order in disorder strength
when both chiral subbands are occupied. In the situation that only the majority
subband is occupied, all terms are finite in the weak scattering limit and the
total anomalous Hall conductivity is dominated by skew scattering. We compare
our results to previous treatments and resolve some of the discrepancies
present in the literature.


title: Morse theory in path space

abstract:
  We consider the path space of a curved manifold on which a point particle is
introduced in a conservative physical system with constant total energy to
formulate its action functional and geodesic equation together with breaks on
the path. The second variation of the action functional is exploited to yield
the geodesic deviation equation and to discuss the Jacobi fields on the curved
manifold. We investigate the topology of the path space using the action
functional on it and its physical meaning by defining the gradient of the
action functional, the space of bounded flow energy solutions and the moduli
space associated with the critical points of the action functional. We also
consider the particle motion on the $n$-sphere $S^{n}$ in the conservative
physical system to discuss explicitly the moduli space of the path space and
the corresponding homology groups.


title:
On Cuspidal Representations of General Linear Groups over Discrete
  Valuation Rings

abstract:
  We define a new notion of cuspidality for representations of $\GL_n$ over a
finite quotient $\Oh_k$ of the ring of integers $\Oh$ of a non-Archimedean
local field $F$ using geometric and infinitesimal induction functors, which
involve automorphism groups $G_\lambda$ of torsion $\Oh$\nobreakdash-modules.
When $n$ is a prime, we show that this notion of cuspidality is equivalent to
strong cuspidality, which arises in the construction of supercuspidal
representations of $\GL_n(F)$. We show that strongly cuspidal representations
share many features of cuspidal representations of finite general linear
groups. In the function field case, we show that the construction of the
representations of $\GL_n(\Oh_k)$ for $k\geq 2$ for all $n$ is equivalent to
the construction of the representations of all the groups $G_\lambda$. A
functional equation for zeta functions for representations of $\GL_n(\Oh_k)$ is
established for representations which are not contained in an infinitesimally
induced representation. All the cuspidal representations for $\GL_4(\Oh_2)$ are
constructed. Not all these representations are strongly cuspidal.


title:
High-Tc superconductivity originated from strong spin-charge
  correlation: indication from linear temperature dependence of resistivity

abstract:
  Both the highest- and the linear temperature dependence of the resistivity in
wide temperature range appear at the optimally doped regions of Cu-based
superconductors1,2,3,4,5, and the highest- of Fe-based superconductors6,7 are
also associated with the linear temperature dependence of the resistivity in
normal states near superconducting states. This means that the high temperature
superconductivity and the linear temperature dependence of the resistivity
should be dominated by the same mechanism. This letter on theoretic calculation
clearly shows that strong spin-charge correlation dominated resistivity behaves
the linear temperature dependence, thus high-temperature superconductivity
should be induced by strong spin-charge correlation.


title: The physics of strong magnetic fields in neutron stars

abstract:
  In this paper we present a new result, namely that the primal magnetic field
of the collapsed core during a supernova explosion will, as a result of the
conservation of magnetic flux, receive a massive boost to more than 90 times
its original value by the Pauli paramagnetization of the highly degenerate
relativistic electron gas just after the formation of the neutron star. Thus,
the observed super-strong magnetic field of neutron stars may originate from
the induced Pauli paramagnetization of the highly degenerate relativistic
electron gas in the interior of the neutron star. We therefore have an
apparently natural explanation for the surface magnetic field of a neutron
star.


title:
Quantum transport in mesoscopic ring structures: Effects of impurities,
  long-range hopping and interactions

abstract:
  In the present review we make a comprehensive analysis of our understanding
on electron transport in mesoscopic single-channel rings and multi-channel
cylinders within a tight-binding framework. A spectacular mesoscopic phenomenon
where a non-decaying current circulates in a small conducting loop is observed
upon the application of an Aharonov-Bohm flux $\phi$. To understand its
behavior one has to focus attention on the interplay of quantum phase
coherence, electron-electron correlation and disorder. This is a highly
challenging problem and here we address it for some simple loop geometries with
their detailed energy band structures to get an entire picture at the
microscopic level. The behavior of low-field magnetic response of persistent
current and its temperature dependence are also discussed.


title: Teleportation of massive particles without shared entanglement

abstract:
  We propose a method for quantum state transfer from one atom laser beam to
another via an intermediate optical field, using Raman incoupling and
outcoupling techniques. Our proposal utilises existing experimental
technologies to teleport macroscopic matter waves over potentially large
distances without shared entanglement.


title: N = 2 Supersymmetric QED equivalence of N = 2 Volkov-Akulov model

abstract:
  We show explicitly in two dimensional spacetime (d = 2) that the N = 2
Volkov-Akulov model is equivalent to the spontaneously broken linear
supersymmetry (LSUSY) interacting gauge theory for N = 2 vector and N = 2
scalar supermultiplets. The local gauge interaction of LSUSY is induced by the
specific composite structure of the auxiliary fields and the consequent
transformations.


title:
Nanocrystals in silicon photonic crystal standing-wave cavities as
  spin-photon phase gates for quantum information processing

abstract:
  By virtue of a silicon high-Q photonic crystal nanocavity, we propose and
examine theoretically interactions between a stationary electron spin qubit of
a semiconductor nanocrystal and a flying photon qubit. Firstly, we introduce,
derive and demonstrate for the first time the explicit conditions towards
realization of a spin-photon two-qubit phase gate, and propose these
interactions as a generalized quantum interface for quantum information
processing. Secondly, we examine novel single-spin-induced reflections as
direct evidence of intrinsic bare and dressed modes in our coupled
nanocrystal-cavity system. The excellent physical integration of this silicon
system provides tremendous potential for large-scale quantum information
processing.


title:
A growth walk model for estimating the canonical partition function of
  Interacting Self Avoiding Walk

abstract:
  We have explained in detail why the canonical partition function of
Interacting Self Avoiding Walk (ISAW), is exactly equivalent to the
configurational average of the weights associated with growth walks, such as
the Interacting Growth Walk (IGW), if the average is taken over the entire
genealogical tree of the walk. In this context, we have shown that it is not
always possible to factor the the density of states out of the canonical
partition function if the local growth rule is temperature-dependent. We have
presented Monte Carlo results for IGWs on a diamond lattice in order to
demonstrate that the actual set of IGW configurations available for study is
temperature-dependent even though the weighted averages lead to the expected
thermodynamic behavior of Interacting Self Avoiding Walk (ISAW).


title:
The $(g,K)$-module structures of principal series representations of
  $Sp(3,R)$

abstract:
  We describe explicitly the whole structures of the $(g,K)$-modules of
principal series representations of $Sp(3,R)$. We apply this result to
determine the holonomic system characterizing those Whittaker functions.


title:
Pair Correlation Functions and a Free-Energy Functional for the Nematic
  Phase

abstract:
  In this paper we have presented the calculation of pair correlation functions
in a nematic phase for a model of spherical particles with the long-range
anisotropic interaction from the mean spherical approximation(MSA) and the
Percus-Yevick (PY) integral equation theories. The results found from the MSA
theory have been compared with those found analytically by Holovko and
Sokolovska (J. Mol. Liq. $\bf 82$, 161(1999)). A free energy functional which
involves both the symmetry conserving and symmetry broken parts of the direct
pair correlation function has been used to study the properties of the nematic
phase. We have also examined the possibility of constructing a free energy
functional with the direct pair correlation function which includes only the
principal order parameter of the ordered phase and found that the resulting
functional gives results that are in good agreement with the original
functional. The isotropic-nematic transition has been located using the grand
thermodynamic potential. The PY theory has been found to give nematic phase
with pair correlation function harmonic coefficients having all the desired
features. In a nematic phase the harmonic coefficient of the total pair
correlation function $h({\bf x_1},{\bf x_2})$ connected with the correlations
of the director transverse fluctuations should develop a long-range tail. This
feature has been found in both the MSA and PY theories.


title:
Far-infrared distributions in nearby spiral galaxies NGC2841 and NGC2976
  observed with AKARI/FIS

abstract:
  Far-infrared (IR) images of the nearby Sb galaxy NGC2841 and the Sc galaxy
NGC2976 at wavelengths of 65, 90, 140, and 160 um have been obtained with the
Far-Infrared Surveyor (FIS) onboard AKARI. Both galaxies reveal similar
morphologies of dust rings. They are, however, significantly different in the
dust temperature: a cold (21 K) ring for NGC2841 and a warm (30 K) ring for
NGC2976, which presumably reflects the difference in the origin of the ring
structure for the different Hubble type of the galaxy. In addition to the dust
ring structure, a warm dust component is detected from the central region of
NGC2841, which may be attributed to the heating by its Low-Ionization Nuclear
Emission-line Region nucleus. As for NGC2976, an extended dust component is
observed along the minor axis, which shows a distribution somewhat asymmetrical
to the galactic disk; this might be associated with the HI bridge in the
M81/M82 group that NGC2976 belongs to. By taking advantage of a wealth of the
far-IR bands of the FIS, it is demonstrated that the spectral energy
distribution of NGC2841 is spatially more variable than that of NGC2976.


title:
From a unstable periodic orbit to Lyapunov exponent and macroscopic
  variable in a Hamiltonian lattice : Periodic orbit dependencies

abstract:
  We study which and how a periodic orbit in phase space links to both the
largest Lyapunov exponent and the expectation values of macroscopic variables
in a Hamiltonian system with many degrees of freedom. The model which we use in
this paper is the discrete nonlinear Schr\"odinger equation. Using a method
based on the modulational estimate of a periodic orbit, we predict the largest
Lyapunov exponent and the expectation value of a macroscopic variable. We show
that (i) the predicted largest Lyapunov exponent generally depends on the
periodic orbit which we employ, and (ii) the predicted expectation value of the
macroscopic variable does not depend on the periodic orbit at least in a high
energy regime. In addition, the physical meanings of these dependencies are
considered.


title: In-orbit focal adjustment of the AKARI telescope with IRC images

abstract:
  AKARI currently in space carries onboard a cryogenically-cooled lightweight
telescope with silicon carbide mirrors. The wavefront error of the AKARI
telescope obtained in laboratory measurements at 9 K showed that expected
in-orbit imaging performance was diffraction-limited at a wavelength of 6.2 um.
The AKARI telescope has a function of focus adjustment by shifting the
secondary mirror in parallel to the optical axis. On the 4th day after the
jettison of the cryostat aperture lid in the orbit, we observed a star with the
InfraRed Camera (IRC) onboard AKARI. Since the initial star images observed in
the near-infrared (IR) bands were significantly blurred, we twice moved the
secondary mirror for the focal adjustment based on the results of model
analyses as well as data analyses of the near-IR images. In consequence, we
have successfully adjusted the focus of the telescope. The in-orbit imaging
performance thus obtained for the AKARI telescope is diffraction-limited at a
wavelength of 7.3 um, slightly degraded from that expected from the laboratory
measurement.


title: On Gauge Symmetry Breaking via Euclidean Time Component of Gauge Fields

abstract:
  We study gauge theories with/without an extra dimension at finite
temperature, in which there are two kinds of order parameters of gauge symmetry
breaking. The one is the zero mode of the gauge field for the Euclidean time
direction and the other is that for the direction of the extra dimension. We
evaluate the effective potential for the zero modes in one-loop approximation
and investigate the vacuum configuration in detail. Our analyses show that
gauge symmetry can be broken only through the zero mode for the direction of
the extra dimension and no nontrivial vacuum configuration of the zero mode for
the Euclidean time direction is found.


title:
Fidelity and Quantum phase transition for the Heisenberg chain with the
  next-nearest-neighbor interaction

abstract:
  In this paper, we investigate the fidelity for the Heisenberg chain with the
next-nearest-neighbor interaction (or the $J_1-J_2$ model) and analyze its
connections with quantum phase transition. We compute the fidelity between the
ground states and find that the phase transition point of the $J_1-J_2$ model
can not be well characterized by the ground state fidelity for finite-size
systems. Instead, we introduce and calculate the fidelity between the first
excited states. Our results show that the quantum transition can be well
characterized by the fidelity of the first excited state even for a small-size
system.


title: Modeling Hourly Ozone Concentration Fields

abstract:
  This paper presents a dynamic linear model for modeling hourly ozone
concentrations over the eastern United States. That model, which is developed
within an Bayesian hierarchical framework, inherits the important feature of
such models that its coefficients, treated as states of the process, can change
with time. Thus the model includes a time--varying site invariant mean field as
well as time varying coefficients for 24 and 12 diurnal cycle components. This
cost of this model's great flexibility comes at the cost of computational
complexity, forcing us to use an MCMC approach and to restrict application of
our model domain to a small number of monitoring sites. We critically assess
this model and discover some of its weaknesses in this type of application.


title:
Gemini Observations of Disks and Jets in Young Stellar Objects and in
  Active Galaxies

abstract:
  We present first results from the Near-infrared Integral Field Spectrograph
(NIFS) located at Gemini North. For the active galaxies Cygnus A and Perseus A
we observe rotationally-supported accretion disks and adduce the existence of
massive central black holes and estimate their masses. In Cygnus A we also see
remarkable high-excitation ionization cones dominated by photoionization from
the central engine. In the T-Tauri stars HV Tau C and DG Tau we see
highly-collimated bipolar outflows in the [Fe II] 1.644 micron line, surrounded
by a slower molecular bipolar outflow seen in the H_2 lines, in accordance with
the model advocated by Pyo et al. (2002).


title: The model equation of soliton theory

abstract:
  We consider an hierarchy of integrable 1+2-dimensional equations related to
Lie algebra of the vector fields on the line. The solutions in quadratures are
constructed depending on $n$ arbitrary functions of one argument. The most
interesting result is the simple equation for the generating function of the
hierarchy which defines the dynamics for the negative times and also has
applications to the second order spectral problems. A rather general theory of
integrable 1+1-dimensional equations can be developed by study of polynomial
solutions of this equation under condition of regularity of the corresponding
potentials.


title: Free-Energy Landscape of Kinesin by a Realistic Lattice Model

abstract:
  Structural fluctuations in the thermal equilibrium of the kinesin motor
domain are studied using a lattice protein model with Go interactions. By means
of the multi-self-overlap ensemble (MSOE) Monte Carlo method and the principal
component analysis (PCA), the free-energy landscape is obtained. It is shown
that kinesins have two subdomains that exhibit partial folding/unfolding at
functionally important regions: one is located around the nucleotide binding
site and the other includes the main microtubule binding site. These subdomains
are consistent with structural variability that was reported recently based on
experimentally-obtained structures. On the other hand, such large structural
fluctuations have not been captured by B-factor or normal mode analyses. Thus,
they are beyond the elastic regime, and it is essential to take into account
chain connectivity for studying the function of kinesins.


title:
A discrete time neural network model with spiking neurons. Rigorous
  results on the spontaneous dynamics

abstract:
  We derive rigorous results describing the asymptotic dynamics of a discrete
time model of spiking neurons introduced in \cite{BMS}. Using symbolic dynamic
techniques we show how the dynamics of membrane potential has a one to one
correspondence with sequences of spikes patterns (``raster plots''). Moreover,
though the dynamics is generically periodic, it has a weak form of initial
conditions sensitivity due to the presence of a sharp threshold in the model
definition. As a consequence, the model exhibits a dynamical regime
indistinguishable from chaos in numerical experiments.


title: Magnetoelectronic states of a monolayer graphite

abstract:
  The Peierl's tight-binding model, with the band Hamiltonian matrix, is used
to calculate the magnetoelectronic structure of a monolayergraphite. There are
many flat Landau levels and some oscillatory Landau levels. The low
Landau-level energies are characterized by a simple relation, not for others.
State degeneracy is, respectively, fourfold degenerate and doubly degenerate at
low and high energies. The level spacing declines quickly and then grows
gradually in the increase of state energy. The main features of electronic
properties are directly reflected in density of states. The predicted results
could be verified by the optical spectroscopy.


title:
Delocalizing transition in one-dimensional condensates in optical
  lattices due to inhomogeneous interactions

abstract:
  It is shown that inhomogeneous nonlinear interactions in a Bose-Einstein
condensate loaded in an optical lattice can result in delocalizing transition
in one dimension, what sharply contrasts to the known behavior of discrete and
periodic systems with homogeneous nonlinearity. The transition can be
originated either by decreasing the amplitude of the linear periodic potential
or by the change of the mean value of the periodic nonlinearity. The dynamics
of the delocalizing transition is studied.


title: Neutrino number asymmetry and cosmological birefringence

abstract:
  We study a new type of effective interactions in terms of the $CPT$-even
dimension-six Chern-Simons-like term, which could originate from superstring
theory, to generate the cosmological birefringence. We use the neutrino number
asymmetry to induce a sizable rotation polarization angle in the data of the
cosmic microwave background radiation polarization. The combined effect of the
new term and the neutrino asymmetry provides an alternative way to understand
the birefringence.


title:
Comparative Direct Analysis of Type Ia Supernova Spectra. III.
  Premaximum

abstract:
  A comparative study of spectra of 21 Type Ia supernovae (SNe Ia) obtained
about one week before maximum light, and 8 spectra obtained 11 or more days
before maximum, is presented. To a large extent the premaximum spectra exhibit
the defining characteristics of the four groups defined in Paper II
(core-normal, broad-line, cool, and shallow-silicon). Comparisons with SYNOW
synthetic spectra show that all strong features and most weak ones can be
accounted for in a plausible way. The issues of detached high-velocity
features, the possible ubiquity of carbon clumps, the maximum detectable ejecta
velocities, and the possibility of blueshifted emission-line peaks are
discussed.


title: A mechanism for phase separation in copper oxide superconductors

abstract:
  A two-band Hubbard model is used to describe the band structure and phase
separation (PS) in multiband superconductors, especially in cuprates. We
predict a large peak in the density of states at the Fermi level in the case of
optimum doping, corresponding to the minimum energy difference between the
centers of two hole bands. For strong interband hybridization, a
metal-insulator transition occurs near this optimum doping level. We suggest a
mechanism of PS related to the redistribution of holes between two Hubbard
bands rather than to the usual antiferromagnetic correlations. We show that the
critical superconducting temperature $T_c$ can be about its maximum value
within a wide range of doping levels due to PS.


title: Enumeration of curves via floor diagrams

abstract:
  In this note we compute some enumerative invariants of real and complex
projective spaces by means of some enriched graphs called floor diagrams.


title: The Jones and Alexander polynomials for singular links

abstract:
  We extend the state models for Jones and Alexander polynomials of classical
links to state models of 2-variable polynomials in the case of singular links.
Moreover, we extend both of them to polynomials with d+1 variables for long
singular knots with exactly d double points. These extensions can detect
non-invertibility of long singular knots.


title: Off-site continuums and methods of their mathematical description

abstract:
  The hypothesis concerning the off-site continuum existence is investigated
from the point of view of the mathematical theory of sets. The principles and
methods of the mathematical description of the physical objects from different
off-site continuums are introduced and discussed. There are also proposed the
mathematical methods of the description of the off-site continuum observable
structures and the visual perception of its physical objects from the continuum
of the observer.


title: Screening length and the direction of plasma winds

abstract:
  We study the screening length of a heavy quark-antiquark pair in strongly
coupled gauge theory plasmas flowing at velocity v following a proposal by Liu,
Rajagopal, and Wiedemann. We analyze the screening length as the direction of
the plasma winds vary. To leading order in v, this angle-dependence can be
studied analytically for many theories by extending our previous formalism. We
show that the screening length is locally a minimum (maximum) when the pair is
perpendicular (parallel) to the plasma winds, which has been observed for the
N=4 plasma. Also, we compare AdS/CFT results with weak coupling ones, and we
discuss the subleading dependence on v for the Dp-brane.


title:
Superscaling and Neutral Current Quasielastic Neutrino-Nucleus
  Scattering beyond the Relativistic Fermi Gas Model

abstract:
  The superscaling analysis is extended to include quasielastic (QE) scattering
via the weak neutral current of neutrinos and antineutrinos from nuclei. The
scaling function obtained within the coherent density fluctuation model (used
previously in calculations of QE inclusive electron and charge-changing (CC)
neutrino scattering) is applied to neutral current neutrino and antineutrino
scattering with energies of 1 GeV from $^{12}$C with a proton and neutron
knockout (u-channel inclusive processes). The results are compared with those
obtained using the scaling function from the relativistic Fermi gas model and
the scaling function as determined from the superscaling analysis (SuSA) of QE
electron scattering.


title: Spherical harmonics and the icosahedron

abstract:
  We define a sextic invariant J on the seven-dimensional space of degree three
spherical harmonics and show that J is positive if and only if the nodal set of
the spherical harmonic contains the vertices of exactly two regular icosahedra.
The proof uses the geometry of the Clebsch diagonal cubic surface, Atiyah's
classification of vector bundles on an elliptic curve and a Fano threefold
introduced by Mukai.


title: Sign refinement for combinatorial link Floer homology

abstract:
  Link Floer homology is an invariant for links which has recently been
described entirely in a combinatorial way. Originally constructed with mod 2
coefficients, it was generalized to integer coefficients thanks to a sign
refinement. In this paper, thanks to the spin extension of the permutation
group we give an alternative construction of the combinatorial link Floer chain
complex associated to a grid diagram with integer coefficients. We prove that
the filtered homology of this complex is an invariant for the link and that it
gives the previous sign refinement by means of a 2-cohomological class
corresponding to the spin extension of the permutation group.


title: The discovery of a massive supercluster at z=0.9 in the UKIDSS DXS

abstract:
  We analyse the first publicly released deep field of the UKIDSS Deep
eXtragalactic Survey (DXS) to identify candidate galaxy over-densities at z~1
across ~1 sq. degree in the ELAIS-N1 field. Using I-K, J-K and K-3.6um colours
we identify and spectroscopically follow-up five candidate structures with
Gemini/GMOS and confirm they are all true over-densities with between five and
nineteen members each. Surprisingly, all five structures lie in a narrow
redshift range at z=0.89+/-0.01, although they are spread across 30Mpc on the
sky. We also find a more distant over-density at z=1.09 in one of the
spectroscopic survey regions. These five over-dense regions lying in a narrow
redshift range indicate the presence of a supercluster in this field and by
comparing with mock cluster catalogs from N-body simulations we discuss the
likely properties of this structure. Overall, we show that the properties of
this supercluster are similar to the well-studied Shapley and Hercules
superclusters at lower redshift.


title:
Anomalous magnetoresistance of EuB$_{5.99}$C$_{0.01}$: Enhancement of
  magnetoresistance in systems with magnetic polarons

abstract:
  We present results of measurements of electrical, magnetic and thermal
properties of EuB$_{5.99}$C$_{0.01}$. The observed anomalously large negative
magnetoresistance as above, so below the Curie temperature of ferromagnetic
ordering $T_C$ is attributed to fluctuations in carbon concentration. Below
$T_C$ the carbon richer regions give rise to helimagnetic domains, which are
responsible for an additional scattering term in the resistivity, which can be
suppressed by a magnetic field. Above $T_C$ these regions prevent the process
of percolation of magnetic polarons (MPs), acting as "spacers" between MPs. We
propose that such "spacers", being in fact volumes incompatible with existence
of MPs, may be responsible for the decrease of the percolation temperature and
for the additional (magneto)resistivity increase in systems with MPs.


title: Rms-flux relation of Cyg X-1 with RXTE: dipping and nondipping cases

abstract:
  The rms (root mean square) variability is the parameter for understanding the
emission temporal properties of X-ray binaries (XRBs) and active galactic
nuclei (AGN).
  The rms-flux relation with Rossi X-ray Timing Explorer (RXTE) data for the
dips and nondip of black hole Cyg X-1 has been investigated in this paper. Our
results show that there exist the linear rms-flux relations in the frequency
range 0.1-10 Hz for the dipping light curve. Moreover, this linear relation
still remains during the nondip regime, but with the steeper slope than that of
the dipping case in the low energy band. For the high energy band, the slopes
of the dipping and nondipping cases are hardly constant within errors. The
explanations of the results have been made by means of the ``Propagating
Perturbation'' model of Lyubarskii (1997).


title: The early evolution of tidal dwarf galaxies

abstract:
  Context: Dwarf galaxies can arise from self-gravitating structures emerging
from tidal tails. What fraction of the known dwarf galaxies in the Local
Universe can have this origin is still a matter of debate. Aims: In our effort
to understand the origin and evolution of tidal dwarf galaxies and their
correspondence with local objects, the first step is to understand how these
galaxies (which are supposed to have a limited amount of dark matter) react to
the feedback of the ongoing star formation. Methods: We make use of 2-D
chemodynamical calculations in order to study the early evolution of isolated,
dark matter-free dwarf galaxies. We present models in which feedback parameters
are varied. We also compare the results with dark matter-dominated dwarf galaxy
models. Results: All the considered models show that the star formation
proceeds for more than 300 Myr, therefore dwarf galaxies without large dark
matter halos are not necessarily quickly destroyed. The chemical evolution of
these objects is consistent with the main chemical properties of the dSphs of
the Local Group. Models with large dark matter halos show results consistent
with models free of dark matter, indicating that the distribution of gas is
more important than the depth of the potential well in determining the global
behaviour of dSph-sized dwarf galaxies.


title: Mean field theory of spin glasses: statics and dynamics

abstract:
  In these lectures I will review some theoretical results that have been
obtained for spin glasses. I will concentrate my attention on the formulation
of the mean field approach and on its numerical and experimental verifications.
I will present the various hypothesis at the basis of the theory and I will
discuss their mathematical and physical status.


title:
A novel L-band imaging search for giant planets in the Tucana and Beta
  Pictoris moving groups

abstract:
  The paper presents results from a small survey of 22 young, nearby stars that
was designed to detect substellar companions and ultimately giant extrasolar
planets down to Jupiter masses. The targets are members of the Tucana and Beta
Pictoris moving groups apart from the somewhat older star HIP 71395 that has a
radial velocity trend suggesting a massive planet in large orbit. The survey
was carried out in the L-band using adaptive optics assisted imaging with
NAOS-CONICA (NACO) at the VLT. The chosen observation wavelength is well suited
to search for close companions around young stars and delivers unprecedented
detection limits. The presented technique reaches some of the best
sensitivities as of today and is currently the most sensitive method for the
contrast limited detection of substellar companions that are cooler than about
1000K. The companion to 51 Eri, GJ 3305, was found to be a very close binary on
an eccentric orbit. No substellar companions were found around the target
stars, although the method permitted to detect companions down to a few Jupiter
masses at orbital distances of typically 5 astronomical units. A planet with a
mass >1 M_Jup at distances >5 AU around AU Mic can be excluded at the time of
our observations. The absence of detected planets sets constraints on the
frequency distribution and maximum orbital distance of giant exoplanets. For
example, a radial distribution power law index of 0.2 in combination with a
maximum orbital radius exceeding 30 AU can be rejected at a 90% confidence
level.


title:
Total singular value decomposition. Robust SVD, regression and
  location-scale

abstract:
  Singular Value Decomposition (SVD) is the basic body of many statistical
algorithms and few users question whether SVD is properly handling its job.
  SVD aims at evaluating the decomposition that best approximates a data
matrix, given some rank restriction. However often we are interested in the
best components of the decomposition rather than in the best approximation .
This conflict of objectives leads us to introduce {\em Total SVD}, where the
word "Total" is taken as in "Total" least squares.
  SVD is a least squares method and, therefore, is very sensitive to gross
errors in the data matrix. We make SVD robust by imposing a weight to each of
the matrix entries. Breakdown properties are excellent.
  Algorithmic aspects are handled; they rely on high dimension fixed point
computations.


title:
Multiparty quantum secret sharing with pure entangled states and decoy
  photons

abstract:
  We present a scheme for multiparty quantum secret sharing of a private key
with pure entangled states and decoy photons. The boss, say Alice uses the
decoy photons, which are randomly in one of the four nonorthogonal
single-photon states, to prevent a potentially dishonest agent from
eavesdropping freely. This scheme requires the parties of communication to have
neither an ideal single-photon quantum source nor a maximally entangled one,
which makes this scheme more convenient than others in a practical application.
Moreover, it has the advantage of having high intrinsic efficiency for qubits
and exchanging less classical information in principle.


title:
Controlled Teleportation of an Arbitrary Multi-Qudit State in a General
  Form with d-Dimensional Greenberger-Horne-Zeilinger States

abstract:
  A general scheme for controlled teleportation of an arbitrary multi-qudit
state with d-dimensional Greenberger-Horne-Zeilinger (GHZ) states is proposed.
For an arbitrary m-qudit state, the sender Alice performs m generalized
Bell-state projective measurements on her 2m qudits and the controllers need
only take some single-particle measurements. The receiver Charlie can
reconstruct the unknown m-qudit state by performing some single-qudit unitary
operations on her particles if she cooperates with all the controllers. As the
quantum channel is a sequence of maximally entangled GHZ states, the intrinsic
efficiency for qudits in this scheme approaches 100% in principle.


title: An Algorithm for the Continuous Morlet Wavelet Transform

abstract:
  This article consists of a brief discussion of the energy density over time
or frequency that is obtained with the wavelet transform. Also an efficient
algorithm is suggested to calculate the continuous transform with the Morlet
wavelet. The energy values of the Wavelet transform are compared with the power
spectrum of the Fourier transform. Useful definitions for power spectra are
given. The focus of the work is on simple measures to evaluate the transform
with the Morlet wavelet in an efficient way. The use of the transform and the
defined values is shown in some examples.


title: Evolutionary Dilemmas in a Social Network

abstract:
  We simulate the prisoner's dilemma and hawk-dove games on a real social
acquaintance network. Using a discrete analogue of replicator dynamics, we show
that surprisingly high levels of cooperation can be achieved, contrary to what
happens in unstructured mixing populations. Moreover, we empirically show that
cooperation in this network is stable with respect to invasion by defectors.


title: Reading Off Kurosh Decompositions

abstract:
  Geometric methods proposed by Stallings for treating finitely generated
subgroups of free groups were successfully used by many authors to solve a wide
collection of decision problems for free groups and their subgroups.
  In the present paper we employ our generalized Stallings' folding method to
introduce a procedure, which given a subgroup H of a free product of finite
groups reads off its Kurosh decomposition from the subgroup graph of H.


title:
Development of innovative micropattern gaseous detectors with resistive
  electrodes and first results of their applications

abstract:
  The paper summarizes our latest progress in the development of newly
introduced micro pattern gaseous detectors with resistive electrodes. These
resistive electrodes protect the detector and the front-end electronics in case
of occasional discharges and thus make the detectors very robust and reliable
in operation. As an example, we describe in greater detail a new recently
developed GEM-like detector, fully spark-protected with electrodes made of
resistive kapton. We discovered that all resistive layers used in these studies
(including kapton), that are coated with photosensitive layers, such as CsI,
can be used as efficient photo cathodes for detectors operating in a pulse
counting mode. We describe the first applications of such detectors combined
with CsI or SbCs photo cathodes for the detection of UV photons at room and
cryogenic temperatures.


title: Many concepts and two logics of algorithmic reduction

abstract:
  Within the program of finding axiomatizations for various parts of
computability logic, it was proved earlier that the logic of interactive Turing
reduction is exactly the implicative fragment of Heyting's intuitionistic
calculus. That sort of reduction permits unlimited reusage of the computational
resource represented by the antecedent. An at least equally basic and natural
sort of algorithmic reduction, however, is the one that does not allow such
reusage. The present article shows that turning the logic of the first sort of
reduction into the logic of the second sort of reduction takes nothing more
than just deleting the contraction rule from its Gentzen-style axiomatization.
The first (Turing) sort of interactive reduction is also shown to come in three
natural versions. While those three versions are very different from each
other, their logical behaviors (in isolation) turn out to be indistinguishable,
with that common behavior being precisely captured by implicative
intuitionistic logic. Among the other contributions of the present article is
an informal introduction of a series of new -- finite and bounded -- versions
of recurrence operations and the associated reduction operations. An online
source on computability logic can be found at
http://www.cis.upenn.edu/~giorgi/cl.html


title: Sensitivity of double resonance alignment magnetometers

abstract:
  We present an experimental study of the intrinsic magnetometric sensitivity
of an optical/rf-frequency double resonance magnetometer in which linearly
polarized laser light is used in the optical pumping and detection processes.
We show that a semi-empirical model of the magnetometer can be used to describe
the magnetic resonance spectra. Then, we present an efficient method to predict
the optimum operating point of the magnetometer, i.e., the light power and rf
Rabi frequency providing maximum magnetometric sensitivity. Finally, we apply
the method to investigate the evolution of the optimum operating point with
temperature. The method is very efficient to determine relaxation rates and
thus allowed us to determine the three collisional disalignment cross sections
for the components of the alignment tensor. Both first and second harmonic
signals from the magnetometer are considered and compared.


title: Numerical approach to low-doping regime of the t-J model

abstract:
  We develop an efficient numerical method for the description of a single-hole
motion in the antiferromagnetic background. The method is free of finite-size
effects and allows calculation of physical properties at an arbitrary
wavevector. Methodical increase of the functional space leads to results that
are valid in the thermodynamic limit. We found good agreement with cumulant
expansion, exact- diagonalization approaches on finite lattices as well as
self-consistent Born approximations. The method allows a straightforward
addition of other inelastic degrees of freedom, such as lattice effects. Our
results confirm the existence of a finite quasiparticle weight near the band
minimum for a single hole and the existence of string-like peaks in the
single-hole spectral function.


title:
Light emission patterns from stadium-shaped semiconductor microcavity
  lasers

abstract:
  We study light emission patterns from stadium-shaped semiconductor (GaAs)
microcavity lasers theoretically and experimentally. Performing systematic wave
calculations for passive cavity modes, we demonstrate that the averaging by
low-loss modes, such as those realized in multi-mode lasing, generates an
emission pattern in good agreement with the ray model's prediction. In
addition, we show that the dependence of experimental far-field emission
patterns on the aspect ratio of the stadium cavity is well reproduced by the
ray model.


title:
Strongly modulated transmission of a spin-split quantum wire with local
  Rashba interaction

abstract:
  We investigate the transport properties of ballistic quantum wires in the
presence of Zeeman spin splittings and a spatially inhomogeneous Rashba
interaction. The Zeeman interaction is extended along the wire and produces
gaps in the energy spectrum which allow electron propagation only for spinors
lying along a certain direction. For spins in the opposite direction the waves
are evanescent far away from the Rashba region, which plays the role of the
scattering center. The most interesting case occurs when the magnetic field is
perpendicular to the Rashba field. Then, the spins of the asymptotic
wavefunctions are not eigenfunctions of the Rashba Hamiltonian and the
resulting coupling between spins in the Rashba region gives rise to sudden
changes of the transmission probability when the Fermi energy is swept along
the gap. After briefly examining the energy spectrum and eigenfunctions of a
wire with extended Rashba coupling, we analyze the transmission through a
region of localized Rashba interaction, in which a double interface separates a
region of constant Rashba interaction from wire leads free from spin-orbit
coupling. For energies slightly above the propagation threshold, we find the
ubiquitous occurrence of transmission zeros (antiresonances) which are analyzed
by matching methods in the one-dimensional limit. We find that a a minimal
tight-binding model yields analytical transmission lineshapes of Fano
antiresonance type. More general angular dependences of the external magnetic
field is treated within projected Schroedinger equations with Hamiltonian
matrix elements mixing wavefunction components. Finally, we consider a
realistic quantum wire where the energy subbands are coupled via the Rashba
intersubband coupling term and discuss its effect on the transmission zeros.


title:
Searching for energetic cosmic axions in a laboratory experiment:
  testing the PVLAS anomaly

abstract:
  Astrophysical sources of energetic gamma rays provide the right conditions
for maximal mixing between (pseudo)scalar (axion-like) particles and photons if
their coupling is as strong as suggested by the PVLAS claim. This is
independent of whether or not the axion interaction is standard at all energies
or becomes supressed in the extreme conditions of the stellar interior. The
flux of such particles through the Earth could be observed using a metre long,
Tesla strength superconducting solenoid thus testing the axion interpretation
of the PVLAS anomaly. The rate of events in CAST caused by axions from the Crab
pulsar is also estimated for the PVLAS-favoured parameters.


title: Spin-Polarized Tunneling as a probe of (Ga,Mn)As electronic properties

abstract:
  We present magnetic and tunnel transport properties of
(Ga,Mn)As/(In,Ga)As/(Ga,Mn)As structure before and after adequate annealing
procedure. The conjugate increase of magnetization and tunnel magnetoresistance
obtained after annealing is shown to be associated to the increase of both
exchange energy $\Delta$$_{exch}$ and hole concentration by reduction of the Mn
interstitial atom in the top magnetic electrode. Through a 6x6 band k.p model,
we established general phase diagrams of tunneling magnetoresistance (TMR) and
tunneling anisotropic magnetoresistance (TAMR) \textit{vs.} (Ga,Mn)As Fermi
energy (E$_F$) and spin-splitting parameter (B$_G$). This allows to give a
rough estimation of the exchange energy $\Delta$$_{exch}$=6B$_G$$\simeq$120 meV
and hole concentration p$\simeq1.10^{20}$cm$^{-3}$ of (Ga,Mn)As and beyond
gives the general trend of TMR and TAMR \textit{vs.} the selected hole band
involved in the tunneling transport.


title:
Spatially resolved observation of dipole-dipole interaction between
  Rydberg atoms

abstract:
  We have observed resonant energy transfer between cold Rydberg atoms in
spatially separated cylinders. Resonant dipole-dipole coupling excites the 49s
atoms in one cylinder to the 49p state while the 41d atoms in the second
cylinder are transferred down to the 42p state. We have measured the production
of the 49p state as a function of separation of the cylinders (0 - 80 um) and
the interaction time (0 - 25 us). In addition we measured the width of the
electric field resonances. A full many-body quantum calculation reproduces the
main features of the experiments.


title: Flat modules over valuation rings

abstract:
  Let $R$ be a valuation ring and let $Q$ be its total quotient ring. It is
proved that any singly projective (respectively flat) module is finitely
projective if and only if $Q$ is maximal (respectively artinian). It is shown
that each singly projective module is a content module if and only if any
non-unit of $R$ is a zero-divisor and that each singly projective module is
locally projective if and only if $R$ is self injective. Moreover, $R$ is
maximal if and only if each singly projective module is separable, if and only
if any flat content module is locally projective. Necessary and sufficient
conditions are given for a valuation ring with non-zero zero-divisors to be
strongly coherent or $\pi$-coherent. A complete characterization of
semihereditary commutative rings which are $\pi$-coherent is given. When $R$ is
a commutative ring with a self FP-injective quotient ring $Q$, it is proved
that each flat $R$-module is finitely projective if and only if $Q$ is perfect.


title: A Novel Ordered Phase in SrCu2(BO3)2 under High Pressure

abstract:
  We report results of 11B NMR and susceptibility measurements on the quasi 2D
frustrated dimer spin system SrCu2(BO3)2 under high pressure. At 2.4 GPa and in
a magnetic field of 7 T, NMR lines split with decreasing temperature in two
steps. A gradual splitting below T=30 K breaking the four-fold symmetry of
magnetic response is followed by a further sudden splitting below 3.6 K. The
latter indicates a magnetic phase transition, which is also marked by a kink in
the susceptibility at 1.44 GPa. From the magnetic hyperfine shift data, we
conclude that the low-T phase has a doubled unit cell containing two types of
dimers, one in a nearly singlet state and the other with a finite magnetization
down to T=0.


title: Graph spectra as a systematic tool in computational biology

abstract:
  We present the spectrum of the (normalized) graph Laplacian as a systematic
tool for the investigation of networks, and we describe basic properties of
eigenvalues and eigenfunctions. Processes of graph formation like motif joining
or duplication leave characteristic traces in the spectrum. This can suggest
hypotheses about the evolution of a graph representing biological data. To this
data, we analyze several biological networks in terms of rough qualitative data
of their spectra.


title:
A New Template Family For The Detection Of Gravitational Waves From
  Comparable Mass Black Hole Binaries

abstract:
  In order to improve the phasing of the comparable-mass waveform as we
approach the last stable orbit for a system, various re-summation methods have
been used to improve the standard post-Newtonian waveforms. In this work we
present a new family of templates for the detection of gravitational waves from
the inspiral of two comparable-mass black hole binaries. These new adiabatic
templates are based on re-expressing the derivative of the binding energy and
the gravitational wave flux functions in terms of shifted Chebyshev
polynomials. The Chebyshev polynomials are a useful tool in numerical methods
as they display the fastest convergence of any of the orthogonal polynomials.
In this case they are also particularly useful as they eliminate one of the
features that plagues the post-Newtonian expansion. The Chebyshev binding
energy now has information at all post-Newtonian orders, compared to the
post-Newtonian templates which only have information at full integer orders. In
this work, we compare both the post-Newtonian and Chebyshev templates against a
fiducially exact waveform. This waveform is constructed from a hybrid method of
using the test-mass results combined with the mass dependent parts of the
post-Newtonian expansions for the binding energy and flux functions. Our
results show that the Chebyshev templates achieve extremely high fitting
factors at all PN orders and provide excellent parameter extraction. We also
show that this new template family has a faster Cauchy convergence, gives a
better prediction of the position of the Last Stable Orbit and in general
recovers higher Signal-to-Noise ratios than the post-Newtonian templates.


title: Late time acceleration in 3-brane Brans-Dicke cosmology

abstract:
  In order to investigate more features of the Brans-Dicke cosmology in the
five-dimensional space-time, we explore the solutions of its dynamiacal
systems. A behavior of the universe in its early and late time by means of the
scale factor is considered. As a results, we show that it is possible to avoid
the big rip singularity and to cross the phantom divide line. Furthermore, we
review the dark energy component of the universe and its agreement with the
observation data for this 3-brane Brans Dicke cosmology by means of the
cosmological parameters.


title: Harmonic G-structures

abstract:
  For closed and connected subgroups G of SO(n), we study the energy functional
on the space of G-structures of a (compact) Riemannian manifold M, where
G-structures are considered as sections of the quotient bundle O(M)/G. Then, we
deduce the corresponding first and second variation formulae and the
characterising conditions for critical points by means of tools closely related
with the study of G-structures. In this direction, we show the role in the
energy functional played by the intrinsic torsion of the G-structure. Moreover,
we analyse the particular case G=U(n) for even-dimensional manifolds. This
leads to the study of harmonic almost Hermitian manifolds and harmonic maps
from M into O(M)/U(n).