title: Upgrading the Local Ergodic Theorem for planar semi-dispersing billiards

abstract:
  The Local Ergodic Theorem (also known as the `Fundamental Theorem') gives
sufficient conditions under which a phase point has an open neighborhood that
belongs (mod 0) to one ergodic component. This theorem is a key ingredient of
many proofs of ergodicity for billiards and, more generally, for smooth
hyperbolic maps with singularities. However the proof of that theorem relies
upon a delicate assumption (Chernov-Sinai Ansatz), which is difficult to check
for some physically relevant models, including gases of hard balls. Here we
give a proof of the Local Ergodic Theorem for two dimensional billiards without
using the Ansatz.


title: EF equivalent not isomorphic models

abstract:
  We construct non-isomorphic models M, N, e.g. of cardinality aleph_1 such
that in the Ehrenfeucht-Fraisse game of length zeta < omega_1 the isomorphism
player wins


title: The Automorphism Group of Toric Deligne-Mumford Stacks

abstract:
  We prove that the automorphism group of a toric Deligne-Mumford stack is
isomorphic to the $2$-group associated to the stacky fan.


title: System Design for a Long-Line Quantum Repeater

abstract:
  We present a new control algorithm and system design for a network of quantum
repeaters, and outline the end-to-end protocol architecture. Such a network
will create long-distance quantum states, supporting quantum key distribution
as well as distributed quantum computation. Quantum repeaters improve the
reduction of quantum-communication throughput with distance from exponential to
polynomial. Because a quantum state cannot be copied, a quantum repeater is not
a signal amplifier, but rather executes algorithms for quantum teleportation in
conjunction with a specialized type of quantum error correction called
purification to raise the fidelity of the quantum states. We introduce our
banded purification scheme, which is especially effective when the fidelity of
coupled qubits is low, improving the prospects for experimental realization of
such systems. The resulting throughput is calculated via detailed simulations
of a long line composed of shorter hops. Our algorithmic improvements increase
throughput by a factor of up to fifty compared to earlier approaches, for a
broad range of physical characteristics.


title: Unquenching effects in the quark and gluon propagator

abstract:
  In this work we examine the Fat-Link Irrelevant Clover (FLIC) overlap quark
propagator and the gluon propagator on both dynamical and quenched lattices.
The tadpole-improved Luscher-Weisz gauge action is used in both cases. The
dynamical gauge fields use the FLIC fermion action for the sea quark
contribution. We observe that the presence of sea quarks causes a suppression
of the mass function, quark renormalization function and gluon dressing
function in the infrared. The ultraviolet physics is unaffected.


title: On long increasing chains modulo flat ideals

abstract:
  We prove that e.g. there is no omega_4-sequence in (omega_3)^{omega_3}
increasing modulo the ideal of countable sets.


title: No limit model in inaccessible

abstract:
  Our aim is to improve the negative results i.e. non-existence of limit
models, and the failure of the generic pair property from math.LO/0609636 to
inaccessible lambda as promised there. The motivation is that in [Sh:F756] the
positive results are for lambda measurable hence inaccessible, whereas in
math.LO/0609636 in the negative results obtained only on non-strong limit
cardinals.


title: Noetherian ring with free additive groups

abstract:
  There are Noetherian rings (in fact domains) with a free additive group, in
every infinite cardinality.
  (This is an expanded version of [SgSh:217] which appears in the Abstracts of
the American Mathematical Society 7 (1986): 369.)


title:
Scattering polarization of hydrogen lines from electric-induced atomic
  alignment

abstract:
  We consider a gas of hydrogen atoms illuminated by a broadband, unpolarized
radiation with zero anisotropy. In the absence of external fields, the atomic
J-levels are thus isotropically populated. While this condition persists in the
presence of a magnetic field, we show instead that electric fields can induce
the alignment of those levels. We also show that this electric alignment cannot
occur in a two-term model of hydrogen (e.g., if only the Ly-alpha transition is
excited), or if the level populations are distributed according to Boltzmann's
law.


title:
The Battery-Discharge-Model: A Class of Stochastic Finite Automata to
  Simulate Multidimensional Continued Fraction Expansion

abstract:
  We define an infinite stochastic state machine, the Battery-Discharge-Model
(BDM), which simulates the behaviour of linear and jump complexity of the
continued fraction expansion of multidimensional formal power series, a
relevant security measure in the cryptanalysis of stream ciphers.
  We also obtain finite approximations to the infinite BDM, where polynomially
many states suffice to approximate with an exponentially small error the
probabilities and averages for linear and jump complexity of M-multisequences
of length n over the finite field F_q, for any M, n, q.


title: Spatial pair correlations of atoms in molecular dissociation

abstract:
  We perform first-principles quantum simulations of dissociation of trapped,
spatially inhomogeneous Bose-Einstein condensates of molecular dimers.
Specifically, we study spatial pair correlations of atoms produced in
dissociation after time of flight. We find that the observable correlations may
significantly degrade in systems with spatial inhomogeneity compared to the
predictions of idealized uniform models. We show how binning of the signal can
enhance the detectable correlations and lead to the violation of the classical
Cauchy-Schwartz inequality and relative number squeezing.


title:
Anomalous dispersion in the autocorrelation of ARPES data of
  Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$

abstract:
  We find that peaks in the autocorrelation of angle resolved photoemission
spectroscopy data of Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ in the superconducting
state show dispersive behavior for binding energies smaller than the maximum
superconducting energy gap. For higher energies, though, a striking anomalous
dispersion is observed that is a consequence of the interaction of the
electrons with collective excitations. In contrast, in the pseudogap phase, we
only observe dispersionless behavior for the autocorrelation peaks. The
implications of our findings in regards to Fourier transformed scanning
tunneling spectroscopy data are discussed.


title: Abstract elementary classes near aleph_1

abstract:
  We prove in ZFC, no psi in L_{omega_1,omega}[Q] have unique model of
uncountable cardinality, this confirms theBaldwin conjecture. But we analyze
this in more general terms. We introduce and investigate a.e.c. and also
versions of limit models, and prove some basic properties like representation
by PC class, for any a.e.c. For PC_{aleph_0}-representable a.e.c. we
investigate the conclusion of having not too many non-isomorphic models in
aleph_1 and aleph_2, but have to assume 2^{aleph_0}<2^{aleph_1} and even
2^{aleph_1}<2^{aleph_2}.


title: The Asymptotic Normalized Linear Complexity of Multisequences

abstract:
  We show that the asymptotic linear complexity of a multisequence a in
F_q^\infty that is I := liminf L_a(n)/n and S := limsup L_a(n)/n satisfy the
inequalities M/(M+1) <= S <= 1 and M(1-S) <= I <= 1-S/M, if all M sequences
have nonzero discrepancy infinitely often, and all pairs (I,S) satisfying these
conditions are met by 2^{\aleph_0} multisequences a.
  This answers an Open Problem by Dai, Imamura, and Yang.
  Keywords: Linear complexity, multisequence, Battery Discharge Model,
isometry.


title: Our Peculiar Motion Away from the Local Void

abstract:
  The peculiar velocity of the Local Group of galaxies manifested in the Cosmic
Microwave Background dipole is found to decompose into three dominant
components. The three components are clearly separated because they arise on
distinct spatial scales and are fortuitously almost orthogonal in their
influences. The nearest, which is distinguished by a velocity discontinuity at
~7 Mpc, arises from the evacuation of the Local Void. We lie in the Local Sheet
that bounds the void. Random motions within the Local Sheet are small. Our
Galaxy participates in the bulk motion of the Local Sheet away from the Local
Void. The component of our motion on an intermediate scale is attributed to the
Virgo Cluster and its surroundings, 17 Mpc away. The third and largest
component is an attraction on scales larger than 3000 km/s and centered near
the direction of the Centaurus Cluster. The amplitudes of the three components
are 259, 185, and 455 km/s, respectively, adding collectively to 631 km/s in
the reference frame of the Local Sheet. Taking the nearby influences into
account causes the residual attributed to large scales to align with observed
concentrations of distant galaxies and reduces somewhat the amplitude of motion
attributed to their pull. On small scales, in addition to the motion of our
Local Sheet away from the Local Void, the nearest adjacent filament, the Leo
Spur, is seen to be moving in a direction that will lead to convergence with
our filament. Finally, a good distance to an isolated galaxy within the Local
Void reveals that this dwarf system has a motion of at least 230 km/s away from
the void center. Given the velocities expected from gravitational instability
theory in the standard cosmological paradigm, the distance to the center of the
Local Void must be at least 23 Mpc from our position. The Local Void is large!


title:
MgB2 radio-frequency superconducting quantum interference device
  prepared by atomic force microscope lithography

abstract:
  A new method of preparation of radio-frequency superconducting quantum
interference devices on MgB2 thin films is presented. The variable-thickness
bridge was prepared by a combination of optical lithography and of the
scratching by an atomic force microscope. The critical current of the
nanobridge was 0.35 uA at 4.2 K. Non-contact measurements of the current-phase
characteristics and of the critical current vs. temperature have been
investigated on our structures.


title: Initial Conditions for Bubble Universes

abstract:
  The "bubble universes" of Coleman and De Luccia play a crucial role in string
cosmology. Since our own Universe is supposed to be of this kind, bubble
cosmology should supply definite answers to the long-standing questions
regarding cosmological initial conditions. In particular, it must explain how
an initial singularity is avoided, and also how the initial conditions for
Inflation were established. We argue that the simplest non-anthropic approach
to these problems involves a requirement that the spatial sections defined by
distinguished bubble observers should not be allowed to have arbitrarily small
volumes. Casimir energy is a popular candidate for a quantum effect which can
ensure this, but [because it violates energy conditions] there is a danger that
it could lead to non-perturbative instabilities in string theory. We make a
simple proposal for the initial conditions of a bubble universe, and show that
our proposal ensures that the system is non-perturbatively stable. Thus,
low-entropy conditions can be established at the beginning of a bubble universe
without violating the Second Law of thermodynamics and without leading to
instability in string theory. These conditions are inherited from the ambient
spacetime.


title:
Specht modules and semisimplicity criteria for Brauer and
  Birman--Murakami--Wenzl Algebras

abstract:
  A construction of bases for cell modules of the Birman--Murakami--Wenzl (or
B--M--W) algebra $B_n(q,r)$ by lifting bases for cell modules of $B_{n-1}(q,r)$
is given. By iterating this procedure, we produce cellular bases for B--M--W
algebras on which a large abelian subalgebra, generated by elements which
generalise the Jucys--Murphy elements from the representation theory of the
Iwahori--Hecke algebra of the symmetric group, acts triangularly. The
triangular action of this abelian subalgebra is used to provide explicit
criteria, in terms of the defining parameters $q$ and $r$, for B--M--W algebras
to be semisimple. The aforementioned constructions provide generalisations, to
the algebras under consideration here, of certain results from the Specht
module theory of the Iwahori--Hecke algebra of the symmetric group.


title:
A Challenge to Control Gravity via Applying Electromagnetic
  Low-Frequency Radiation - Theory and Proposed Model Experiments

abstract:
  Including Vaidya metric into the model of Expansive Nondecelerative Universe
allows to localize the energy of gravitational field. A term of effective
gravitational range is introduced and classic Newton potential is substituted
for Yukawa-type potential. It allows to allocate a typical frequency value to
each gravitational field. Derived theoretical conclusions led us to investigate
the effect of electromagnetic field with a precisely predetermined frequency
and intensity on iron. We believe that under certain circumstances a decrease
in iron gravitational mass should be observed. Two model experiments verifying
the theoretical conclusions are proposed.


title: The Infrared Camera (IRC) for AKARI - Design and Imaging Performance

abstract:
  The Infrared Camera (IRC) is one of two focal-plane instruments on the AKARI
satellite. It is designed for wide-field deep imaging and low-resolution
spectroscopy in the near- to mid-infrared (1.8--26.5um) in the pointed
observation mode of AKARI. IRC is also operated in the survey mode to make an
all-sky survey at 9 and 18um. It comprises three channels. The NIR channel
(1.8--5.5um) employs a 512 x 412 InSb array, whereas both the MIR-S
(4.6--13.4um) and MIR-L (12.6--26.5um) channels use 256 x 256 Si:As impurity
band conduction arrays. Each of the three channels has a field-of-view of about
10' x 10' and are operated simultaneously. The NIR and MIR-S share the same
field-of-view by virtue of a beam splitter. The MIR-L observes the sky about
$25' away from the NIR/MIR-S field-of-view. IRC gives us deep insights into the
formation and evolution of galaxies, the evolution of planetary disks, the
process of star-formation, the properties of interstellar matter under various
physical conditions, and the nature and evolution of solar system objects. The
in-flight performance of IRC has been confirmed to be in agreement with the
pre-flight expectation. This paper summarizes the design and the in-flight
operation and imaging performance of IRC.


title:
Statefinder diagnosis for the interacting model of holographic dark
  energy

abstract:
  In this paper, we investigate the holographic dark energy model with
interaction between dark energy and dark matter, from the statefinder
viewpoint. We plot the trajectories of the interacting holographic dark energy
model for different interaction cases as well as for different values of the
parameter $c$ in the statefinder-plane. The statefinder diagrams characterize
the properties of the holographic dark energy and show the discrimination
between the two cases with and without interaction. As a result, we show the
influence of the interaction to the evolution of the universe in the
statefinder diagrams. Moreover, as a complement to the statefinder diagnosis,
we study the interacting holographic dark energy model in the $w-w'$ plane,
which can provide us with a dynamical diagnosis.


title: Dynamical 3-Space: A Review

abstract:
  For some 100 years physics has modelled space and time via the spacetime
concept, with space being merely an observer dependent perspective effect of
that spacetime - space itself had no observer independent existence - it had no
ontological status, and it certainly had no dynamical description. In recent
years this has all changed. In 2002 it was discovered that a dynamical 3-space
had been detected many times, including the Michelson-Morley 1887 light-speed
anisotropy experiment. Here we review the dynamics of this 3-space, tracing its
evolution from that of an emergent phenomena in the information-theoretic
Process Physics to the phenomenological description in terms of a velocity
field describing the relative internal motion of the structured 3-space. The
new physics of the dynamical 3-space is extensively tested against experimental
and astronomical observations, including the necessary generalisation of the
Maxwell, Schrodinger and Dirac equations, leading to a derivation and
explanation of gravity as a refraction effect of quantum matter waves. The flat
and curved spacetime formalisms are derived from the new physics, so explaining
their apparent many successes.


title:
Effect of Dynamical Cosmological Constant in presence of Modified
  Chaplygin Gas for Accelerating Universe

abstract:
  In this paper we have considered the Universe to be filled with Modified Gas
and the Cosmological Constant $\Lambda$ to be time-dependent with or without
the Gravitational Constant $G$ to be time-dependent. We have considered various
phenomenological models for $\Lambda$, viz., $\Lambda\propto\rho,
\Lambda\propto\frac{\dot{a}^{2}}{a^{2}}$ and
$\Lambda\propto\frac{\ddot{a}}{a}$. Using these models it is possible to show
the accelerated expansion of the Universe at the present epoch. Also we have
shown the natures of $G$ and $\Lambda$ over the total age of the Universe.
Using the statefinder parameters we have shown the diagramamtical
representation of the evolution of the Universe starting from radiation era to
$\Lambda$CDM model.


title: Picone identities for half-linear differential equations of fourth order

abstract:
  Picone-type identities are established for half-linear ODEs of fourth order
(one-dimensional p-biLaplacian). It is shown that in the linear case they
reduce to the known identities for fourth order linear ODEs. Picone-type
identity known for two half-linear second-order equations is also generalised
to set of equations greater than two.


title: What happened to the Cosmological QCD Phase Transition?

abstract:
  The scenario that some first-order phase transitions may have taken place in
the early Universe offers us one of the most intriguing and fascinating
questions in cosmology. Indeed, the role played by the latent "heat" or energy
released in the phase transition is highly nontrivial and may lead to some
surprising, important results. In this paper, we take the wisdom that the
cosmological QCD phase transition, which happened at a time between 10^(-5) sec
and 10^(-4) sec or at the temperature of about 150 MeV and accounts for
confinement of quarks and gluons to within hadrons, would be of first order. To
get the essence out of the scenario, it is sufficient to approximate the true
QCD vacuum as one of degenerate theta-vacua and when necessary we try to model
it effectively via a complex scalar field with spontaneous symmetry breaking.
We examine how and when "pasted" or "patched" domain walls are formed, how long
such walls evolve in the long run, and we believe that the significant portion
of dark matter could be accounted for in terms of such domain-wall structure
and its remnants. Of course, the cosmological QCD phase transition happened in
the way such that the false vacua associated with baryons and many other
color-singlet objects did not disappear (that is, using the bag-model language,
there are bags of radius 1.0 fermi for the baryons) - but the amount of the
energy remained in the false vacua is negligible. The latent energy released
due to the conversion of the false vacua to the true vacua, in the form of
"pasted" or "patched" domain walls in the short run and their numerous evolved
objects, should make the concept of the "radiation-dominated" epoch, or of the
"matter-dominated" epoch to be re-examined.


title:
About construction of orthogonal wavelets with compact support and with
  scaling coefficient N

abstract:
  In this paper a simple method of construction of scaling function $\phi (x)$
and orthogonal wavelets with the compact support for any natural coefficient of
scaling $N\ge 2$ is given. Examples of construction of wavelets for
coefficients of scaling N=2 and N=3 are produced.


title: A preferential attachment model with random initial degrees

abstract:
  In this paper, a random graph process ${G(t)}_{t\geq 1}$ is studied and its
degree sequence is analyzed. Let $(W_t)_{t\geq 1}$ be an i.i.d. sequence. The
graph process is defined so that, at each integer time $t$, a new vertex, with
$W_t$ edges attached to it, is added to the graph. The new edges added at time
t are then preferentially connected to older vertices, i.e., conditionally on
$G(t-1)$, the probability that a given edge is connected to vertex i is
proportional to $d_i(t-1)+\delta$, where $d_i(t-1)$ is the degree of vertex $i$
at time $t-1$, independently of the other edges. The main result is that the
asymptotical degree sequence for this process is a power law with exponent
$\tau=\min\{\tau_{W}, \tau_{P}\}$, where $\tau_{W}$ is the power-law exponent
of the initial degrees $(W_t)_{t\geq 1}$ and $\tau_{P}$ the exponent predicted
by pure preferential attachment. This result extends previous work by Cooper
and Frieze, which is surveyed.


title: Maximally Entangled Mixed-State Generation via Local Operations

abstract:
  We present a general theoretical method to generate maximally entangled mixed
states of a pair of photons initially prepared in the singlet polarization
state. This method requires only local operations upon a single photon of the
pair and exploits spatial degrees of freedom to induce decoherence. We report
also experimental confirmation of these theoretical results.


title: Diameters in preferential attachment models

abstract:
  In this paper, we investigate the diameter in preferential attachment (PA-)
models, thus quantifying the statement that these models are small worlds. The
models studied here are such that edges are attached to older vertices
proportional to the degree plus a constant, i.e., we consider affine PA-models.
There is a substantial amount of literature proving that, quite generally,
PA-graphs possess power-law degree sequences with a power-law exponent \tau>2.
  We prove that the diameter of the PA-model is bounded above by a constant
times \log{t}, where t is the size of the graph. When the power-law exponent
\tau exceeds 3, then we prove that \log{t} is the right order, by proving a
lower bound of this order, both for the diameter as well as for the typical
distance. This shows that, for \tau>3, distances are of the order \log{t}. For
\tau\in (2,3), we improve the upper bound to a constant times \log\log{t}, and
prove a lower bound of the same order for the diameter. Unfortunately, this
proof does not extend to typical distances. These results do show that the
diameter is of order \log\log{t}.
  These bounds partially prove predictions by physicists that the typical
distance in PA-graphs are similar to the ones in other scale-free random
graphs, such as the configuration model and various inhomogeneous random graph
models, where typical distances have been shown to be of order \log\log{t} when
\tau\in (2,3), and of order \log{t} when \tau>3.


title:
Systematic improvement of the Momentum Average approximation for the
  Green's function of a Holstein polaron

abstract:
  We show how to systematically improve the Momentum Average (MA)approximation
for the Green's function of a Holstein polaron, bysystematically improving the
accuracy of the self-energy diagrams in such a way that they can still all be
summed efficiently. This allows us to fix some of the problems of the MA
approximation, e.g. we now find the expected polaron+phonon continuum at the
correct location, and a momentum-dependent self-energy. The quantitative
agreement with numerical data is further improved, as expected since the number
of exactly satisfied spectral weight sum rules is increased. The corrections
are found to be larger in lower dimensional systems.


title: On $\pi - \pi$ theorem for manifold pairs with boundaries

abstract:
  Surgery obstruction of a normal map to a simple Poincare pair $(X,Y)$ lies in
the relative surgery obstruction group $L_*(\pi_1(Y)\to\pi_1(X))$. A well known
result of Wall, the so called $\pi$-$\pi$ theorem, states that in higher
dimensions a normal map of a manifold with boundary to a simple Poincare pair
with $\pi_1(X)\cong\pi_1(Y)$ is normally bordant to a simple homotopy
equivalence of pairs. In order to study normal maps to a manifold with a
submanifold, Wall introduced surgery obstruction group for manifold pairs
$LP_*$ and splitting obstruction groups $LS_*$. In the present paper we
formulate and prove for manifold pairs with boundaries the results which are
similar to the $\pi$-$\pi$ theorem. We give direct geometric proofs, which are
based on the original statements of Wall's results and apply obtained results
to investigate surgery on filtered manifolds.


title: Hidden Symmetry of the CKM and Neutrino Mapping Matrices

abstract:
  We propose that the smallness of the light quark masses is related to the
smallness of the T violation in hadronic weak interactions. Accordingly, for
each of the two quark sectors ("upper" and "lower") we construct a 3\times 3
mass matrix in a bases of unobserved quark states, such that the "upper"and
"lower" basis states correspond exactly via the $W^\pm$ transitions in the weak
interaction. In the zeroth approximation of our formulation, we assume T
conservation by making all matrix elements real. In addition, we impose a
"hidden symmetry" (invariance under simultaneous translations of all three
basis quark states in each sector), which ensures a zero mass eigenstate in
each sector.
  Next, we simultaneously break the hidden symmetry and T invariance by
introducing a phase factor e^{i\chi} in the interaction for each sector. The
Jarlskog invariant J_{CKM}, as well as the light quark masses are evaluated in
terms of the parameters of the model. We find a simple relation with
J_{CKM}=(m_dm_s/m_b^2)^{1/2}A\lambda^3\cos(\chi/2), with A and \lambda the
Wolfenstein parameters. Setting J_{CKM}=3.08 \times 10^{-5}, m_b=4.7GeV,
m_s=95MeV, A=0.818 and \lambda=0.227, we find m_d\cos^2(\chi/2) \simeq 2.4MeV,
consistent with the accepted value m_d=3-7MeV.
  We make a parallel proposal for the lepton sectors. With the hidden symmetry
and in the approximation of T invariance, both the masses of e and \nu_1 are
zero. The neutrino mapping matrix V_\nu is shown to be of the same
Harrison-Scott form which is in agreement with experiments. We also examine the
correction due to T violation, and evaluate the corresponding Jarlskog
invariant {\cal J}_\nu.


title:
Riesz bases of root vectors of indefinite Sturm-Liouville problems with
  eigenparameter dependent boundary conditions. II

abstract:
  We consider a regular indefinite Sturm-Liouville problem with two
self-adjoint boundary conditions affinely dependent on the eigenparameter. We
give sufficient conditions under which the root vectors of this Sturm-Liouville
problem can be selected to form a Riesz basis of a corresponding weighted
Hilbert space.


title: Can dark matter be a Bose-Einstein condensate?

abstract:
  We consider the possibility that the dark matter, which is required to
explain the dynamics of the neutral hydrogen clouds at large distances from the
galactic center, could be in the form of a Bose-Einstein condensate. To study
the condensate we use the non-relativistic Gross-Pitaevskii equation. By
introducing the Madelung representation of the wave function, we formulate the
dynamics of the system in terms of the continuity equation and of the
hydrodynamic Euler equations. Hence dark matter can be described as a
non-relativistic, Newtonian Bose-Einstein gravitational condensate gas, whose
density and pressure are related by a barotropic equation of state. In the case
of a condensate with quartic non-linearity, the equation of state is polytropic
with index $n=1$. To test the validity of the model we fit the Newtonian
tangential velocity equation of the model with a sample of rotation curves of
low surface brightness and dwarf galaxies, respectively. We find a very good
agreement between the theoretical rotation curves and the observational data
for the low surface brightness galaxies. The deflection of photons passing
through the dark matter halos is also analyzed, and the bending angle of light
is computed. The bending angle obtained for the Bose-Einstein condensate is
larger than that predicted by standard general relativistic and dark matter
models. Therefore the study of the light deflection by galaxies and the
gravitational lensing could discriminate between the Bose-Einstein condensate
dark matter model and other dark matter models.


title:
On the fundamental group of $\mathbb R^3$ modulo the Case-Chamberlin
  continuum

abstract:
  It has been known for a long time that the fundamental group of the quotient
of $\RR ^3$ by the Case-Chamberlin continuum is nontrivial. In the present
paper we prove that this group is in fact, uncountable.


title:
Higgs and neutrino sector, EDM and epsilon_K in a spontaneously CP and
  R-parity breaking supersymmetric model

abstract:
  We construct an extension of the supersymmetric standard model where both CP
symmetry and R-parity are spontaneously broken. We study the electroweak
symmetry breaking sector of the model and find minima consistent with the
experimental bounds on Higgs boson masses. Neutrino masses and mixing angles
are generated through both seesaw and bilinear R-parity violation. We show that
the hierarchical mass pattern is obtained, and mixings are consistent with
measured values. Due to the spontaneous CP and R-parity violation, the neutrino
sector is CP violating, and we calculate the corresponding phase. We further
restrict the parameter space to agree with the limits on the electric dipole
moment of the neutron. Finally, we study the CP violation parameter epsilon_K
in the kaon system and show that we obtain results consistent with the
experimental value.


title:
Riesz Bases of Root Vectors of Indefinite Sturm-Liouville problems with
  eigenparameter dependent boundary conditions, I

abstract:
  We consider a regular indefinite Sturm-Liouville problem with two
self-adjoint boundary conditions, one being affinely dependent on the
eigenparameter. We give sufficient conditions under which a basis of each root
subspace for this Sturm-Liouville problem can be selected so that the union of
all these bases constitutes a Riesz basis of a corresponding weighted Hilbert
space.


title:
The Central Kiloparsec of Seyfert and Inactive Host Galaxies: a
  Comparison of Two-Dimensional Stellar and Gaseous Kinematics

abstract:
  We investigate the properties of the two-dimensional distribution and
kinematics of ionised gas and stars in the central kiloparsecs of a matched
sample of nearby active (Seyfert) and inactive galaxies, using the SAURON
Integral Field Unit on the William Herschel Telescope. The ionised gas
distributions show a range of low excitation regions such as star formation
rings in Seyferts and inactive galaxies, and high excitation regions related to
photoionisation by the AGN. The stellar kinematics of all galaxies in the
sample show regular rotation patterns typical of disc-like systems, with
kinematic axes which are well aligned with those derived from the outer
photometry and which provide a reliable representation of the galactic line of
nodes. After removal of the non-gravitational components due to e.g. AGN-driven
outflows, the ionised gas kinematics in both the Seyfert and inactive galaxies
are also dominated by rotation with global alignment between stars and gas in
most galaxies. This result is consistent with previous findings from
photometric studies that the large-scale light distribution of Seyfert hosts
are similar to inactive hosts. However, fully exploiting the two-dimensional
nature of our spectroscopic data, deviations from axisymmetric rotation in the
gaseous velocity fields are identified that suggest the gaseous kinematics are
more disturbed at small radii in the Seyfert galaxies compared with the
inactive galaxies, providing a tentative link between nuclear gaseous streaming
and nuclear activity.


title:
Magnetism in the spiral galaxy NGC 6946: magnetic arms, depolarization
  rings, dynamo modes and helical fields

abstract:
  The spiral galaxy NGC 6946 was observed in total intensity and linear
polarization in five radio bands between 3cm and 21cm. At the inner edge of the
inner gas spiral arm the ordered magnetic field is only mildly compressed and
turns smoothly, to become aligned along the gas arm. Hence the field is not
shocked and is probably connected to the warm, diffuse gas. At larger radii,
two bright magnetic arms between the optical arms are visible in polarized
intensity. The field in the northern magnetic arm is almost totally aligned.
Faraday rotation measures (RM) in these arms are consistent with the
superposition of two low azimuthal dynamo modes. Three more magnetic arms are
discovered in the outer galaxy, located between HI arms. Due to strong Faraday
depolarization the galaxy is not transparent to polarized waves at 18cm and
20cm. The large-scale asymmetry in depolarization with respect to the major
axis may be another indication of large-scale helical fields. Three
depolarization rings of almost zero polarization seen at 20cm are probably
generated by differential Faraday rotation in HII complexes in NGC 6946 of
300-500 pc size. - In the gas/optical spiral arms, the total (mostly turbulent)
magnetic field is amplified to \simeq 20\muG. Its energy density is \simeq 10
times larger than that of the ionized gas and is similar to that of the
turbulent gas motions in the inner galaxy. The magnetic energy exceeds that of
the turbulent energy in the outer galaxy.


title:
Formation of a condensed state with macroscopic number of phonons in
  ultracold Bose gases

abstract:
  A mechanism for the formation of a new type of stationary state with
macroscopical number of phonons in condensed atomic gases is proposed. This
mechanism is based on generating longitudinal phonons as a result of parametric
resonance caused by a permanent modulation of the transverse trap frequency in
an elongated trap. The phonon-phonon interaction predetermines the
self-consistent evolution which is completed with macroscopic population of one
from all levels within the energy interval of parametric amplification. This
level proves to be shifted to the edge of this interval. All other levels end
the evolution with zero population.


title: Entanglement purification and quantum error correction

abstract:
  We give a review on entanglement purification for bipartite and multipartite
quantum states, with the main focus on theoretical work carried out by our
group in the last couple of years. We discuss entanglement purification in the
context of quantum communication, where we emphasize its close relation to
quantum error correction. Various bipartite and multipartite entanglement
purification protocols are discussed, and their performance under idealized and
realistic conditions is studied. Several applications of entanglement
purification in quantum communication and computation are presented, which
highlights the fact that entanglement purification is a fundamental tool in
quantum information processing.


title: Classification of framed links in 3-manifolds

abstract:
  We present a short proof of the following Pontryagin theorem, whose original
proof was complicated and has never been published in details: {\bf Theorem.}
Let $M$ be a connected oriented closed smooth 3-manifold. Let $L_1(M)$ be the
set of framed links in $M$ up to a framed cobordism. Let $\deg:L_1(M)\to
H_1(M;\Z)$ be the map taking a framed link to its homology class. Then for each
$\alpha\in H_1(M;\Z)$ there is a 1-1 correspondence between the set
$\deg\nolimits^{-1}\alpha$ and the group $\Bbb Z_{2d(\alpha)}$, where
$d(\alpha)$ is the divisibility of the projection of $\alpha$ to the free part
of $H_1(M;\Bbb Z)$.


title: Quantum Lie algebras via modified Reflection Equation Algebra

abstract:
  We discuss the consistency of the axioms which the definition of quantum Lie
algebras is usually based on.


title:
Selective-pivot sampling of radial distribution functions in asymmetric
  liquid mixtures

abstract:
  We present a Monte Carlo algorithm for selectively sampling radial
distribution functions and effective interaction potentials in asymmetric
liquid mixtures. We demonstrate its efficiency for hard-sphere mixtures, and
for model systems with more general interactions, and compare our simulations
with several analytical approximations. For interaction potentials containing a
hard-sphere contribution, the algorithm yields the contact value of the radial
distribution function.


title: Dynamical solutions of warped six dimensional supergravity

abstract:
  We derive a new class of exact time dependent solutions in a warped six
dimensional supergravity model. Under the assumptions we make for the form of
the underlying moduli fields, we show that the only consistent time dependent
solutions lead to all six dimensions evolving in time, implying the eventual
decompactification or collapse of the extra dimensions. We also show how the
dynamics affects the quantization of the deficit angle.


title:
Frobenius Curvature, Electromagnetic Strain and Description of
  Photon-like Objects

abstract:
  This paper aims to present a general idea for description of spatially finite
physical objects with a consistent nontrivial translational-rotational
dynamical structure and evolution as a whole, making use of the mathematical
concepts and structures connected with the Frobenius
integrability/nonintegrability theorems and electromagnetic strain quantities.
The idea is based on consideration of {\it nonintegrable} subdistributions of
some appropriate completely integrable distribution (differential system) on a
manifold and then to make use of the corresponding curvatures and
correspondingly directed strains as measures of interaction, i.e. of
energy-momentum exchange among the physical subsystems mathematically
represented by the nonintegrable subdistributions. The concept of photon-like
object is introduced and description (including lagrangian) of such objects in
these terms is given.


title: Grover search algorithm

abstract:
  A quantum algorithm is a set of instructions for a quantum computer, however,
unlike algorithms in classical computer science their results cannot be
guaranteed. A quantum system can undergo two types of operation, measurement
and quantum state transformation, operations themselves must be unitary
(reversible). Most quantum algorithms involve a series of quantum state
transformations followed by a measurement. Currently very few quantum
algorithms are known and no general design methodology exists for their
construction.


title:
Broad-band Spectral Evolution of Scorpius X-1 along its Color-Color
  Diagram

abstract:
  We analyze a large collection of RXTE archive data from April 1997 to August
2003 of the bright X-ray source Scorpius X-1 in order to study the broadband
spectral evolution of the source for different values of the inferred mass
accretion rate by studying energy spectra from selected regions in the Z-track
of its Color-Color Diagram. A two-component model, consisting of a soft thermal
component interpreted as thermal emission from an accretion disk and a thermal
Comptonization component, is unable to fit the whole 3--200 keV energy spectrum
at low accretion rates. Strong residuals in the highest energy band of the
spectrum require the addition of a third component that can be fitted with a
power-law component, that could represent a second thermal Comptonization from
a much hotter plasma, or a hybrid thermal/non-thermal Comptonization. We
discuss the physical implications derived from the results of our analysis,
with a particular emphasis on the hardest part of the X-ray emission and its
possible origins.


title:
Using the average spectrum method to extract dynamics from quantum Monte
  Carlo simulations

abstract:
  We apply the Average Spectrum Method to the problem of getting the excitation
spectrum from imaginary-time quantum Monte Carlo simulations. We show that with
high quality QMC data this method reproduces the dominant spectral features
very well. It is also capable of giving information on the spectrum in regions
dominated by the many-particle continuum of excitations.


title:
Comment on ``Coupled dynamics of atoms and radiation--pressure--driven
  interferometers''

abstract:
  In two recent articles, Meiser and Meystre describe the coupled dynamics of a
dense gas of atoms and an optical cavity pumped by a laser field. They make two
important simplifying assumptions: (i) the gas of atoms forms a regular lattice
and can be replaced by a fictitious mirror, and (ii) the atoms strive to
minimize the dipole potential. We show that the two assumptions are
inconsistent: the configuration of atoms minimizing the dipole potential is not
a perfect lattice. Assumption (ii) is erroneous, as in the strong coupling
regime the dipole force does not arise from the dipole potential. The real
steady state, where the dipole forces vanish, is indeed a regular lattice.
Furthermore, the bistability predicted by Meiser and Meystre does not occur in
this system.


title: Magnetic fields of our Galaxy on large and small scales

abstract:
  Magnetic fields have been observed on all scales in our Galaxy, from AU to
kpc. With pulsar dispersion measures and rotation measures, we can directly
measure the magnetic fields in a very large region of the Galactic disk. The
results show that the large-scale magnetic fields are aligned with the spiral
arms but reverse their directions many times from the inner-most arm (Norma) to
the outer arm (Perseus). The Zeeman splitting measurements of masers in HII
regions or star-formation regions not only show the structured fields inside
clouds, but also have a clear pattern in the global Galactic distribution of
all measured clouds which indicates the possible connection of the large-scale
and small-scale magnetic fields.


title: Bipartite entanglement entropy in fractional quantum Hall states

abstract:
  We present a detailed analysis of bipartite entanglement entropies in
fractional quantum Hall (FQH) states, considering both abelian (Laughlin) and
non-abelian (Moore-Read) states. We derive upper bounds for the entanglement
between two subsets of the particles making up the state. We also consider the
entanglement between spatial regions supporting a FQH state. Using the latter,
we show how the so-called topological entanglement entropy of a FQH state can
be extracted from wavefunctions for a limited number of particles.


title:
Path-phase duality of an interfering particle with
  translational-internal entanglement

abstract:
  The aim of this paper is to revisit the implications of complementarity when
we inject into a Mach Zehnder interferometer particles with internal structure,
prepared in special translational-internal entangled (TIE) states. This
correlation causes the path distinguishability to be phase dependent in
contrast to the standard case. We show that such a TIE state permits us to
detect small phase shifts along with almost perfect path distinguishability,
beyond the constraints imposed by complementarity on simultaneous which-way and
which-phase measurements for standard cases (when distinguishability is
independent of interferometric phase).


title: An Elliptic Type Gradient Estimate For the Schr\"{o}dinger Equation

abstract:
  In this paper, the author discusses the elliptic type gradient estimate for
the solution of the time-dependent Schr\"{o}dinger equations on noncompact
manifolds. As its application, the dimension-free Harnack inequality and the
Liouville type theorem for the Schr\"{o}dinger equation are proved.


title:
Quantized anti de Sitter spaces and non-formal deformation quantizations
  of symplectic symmetric spaces

abstract:
  We realize quantized anti de Sitter space black holes, building Connes
spectral triples, similar to those used for quantized spheres but based on
Universal Deformation Quantization Formulas (UDF) obtained from an oscillatory
integral kernel on an appropriate symplectic symmetric space. More precisely we
first obtain a UDF for Lie subgroups acting on a symplectic symmetric space M
in a locally simply transitive manner. Then, observing that a curvature
contraction canonically relates anti de Sitter geometry to the geometry of
symplectic symmetric spaces, we use that UDF to define what we call
Dirac-isospectral noncommutative deformations of the spectral triples of
locally anti de Sitter black holes. The study is motivated by physical and
cosmological considerations.


title: Search for direct CP-violation in K+- --> 3pi decays by NA48/2

abstract:
  A high precision search for direct CP-violation in K+- --> 3 pi decays was
performed by the NA48/2 experiment at CERN SPS. The asymmetry in the Dalitz
plot linear slopes A_g = (g^+ - g^-)/(g^+ + g^-) is measured to be A^c_g =
(-1.3 +- 2.3)x10^-4 by studying ~3.1x10^9 K+- --> pi+- pi+ pi- decays and A^n_g
= (2.1 +- 1.9)x10^-4 by studying ~91x10^6 K+- --> pi+- pi0 pi0 decays. The
unique double- beam system, the design of the detectors and the method of
analysis provide good control of the instrumental charge asymmetries and allow
to keep the precision of the result limited by statistics, reaching accuracy
one order of magnitude better than in previous experiments.


title:
Asymptotics of the eigenvalues of elliptic systems with fast oscillating
  coefficients

abstract:
  We consider singularly perturbed second order elliptic system in the whole
space with fast oscillating coefficients. We construct the complete asymptotic
expansions for the eigenvalues converging to the isolated ones of the
homogenized system, as well as the complete asymptotic expansions for the
associated eigenfunctions.


title:
A path integral approach to the dynamics of a random chain with rigid
  constraints

abstract:
  In this work the dynamics of a freely jointed random chain which fluctuates
at constant temperature in some viscous medium is studied. The chain is
regarded as a system of small particles which perform a brownian motion and are
subjected to rigid constraints which forbid the breaking of the chain. For
simplicity, all interactions among the particles have been switched off and the
number of dimensions has been limited to two. The problem of describing the
fluctuations of the chain in the limit in which it becomes a continuous system
is solved using a path integral approach, in which the constraints are imposed
with the insertion in the path integral of suitable Dirac delta functions. It
is shown that the probability distribution of the possible conformations in
which the fluctuating chain can be found during its evolution in time coincides
with the partition function of a field theory which is a generalization of the
nonlinear sigma model in two dimensions. Both the probability distribution and
the generating functional of the correlation functions of the positions of the
beads are computed explicitly in a semiclassical approximation for a
ring-shaped chain.


title: Recent results from NA48

abstract:
  Recent results from the experiments NA48, NA48/1 and NA48/2 are presented,
including: direct CP-violation and Dalitz plot slopes measurements for K+- -->
3 pi decays; pi pi scattering effects in K+- --> pi+- pi0 pi0 and Ke4 decays,
as well as Ke4 form factors and branching fraction; measurements on radiative
charged kaons and hyperon decays, semileptonic decays of neutral and charged
kaons; KL --> pi+ pi- branching ratio and |eta+-| measurement; lepton
universality check with Kl2 decays.


title: Fresnel-transform's quantum correspondence and quantum optical ABCD Law

abstract:
  Corresponding to Fresnel transform there exists a unitary operator in quantum
optics theory, which could be named Fresnel operator (FO). We show that the
multiplication rule of FO naturally leads to the quantum optical ABCD law. The
canonical operator methods as mapping of ray-transfer ABCD matrix is explicitly
shown by FO's normally ordered expansion through the coherent state
representation and the technique of integration within an ordered product of
operators. We show that time evolution of the damping oscillator embodies the
quantum optical ABCD law.


title: Secure Two-party Protocols for Point Inclusion Problem

abstract:
  It is well known that, in theory, the general secure multi-party computation
problem is solvable using circuit evaluation protocols. However, the
communication complexity of the resulting protocols depend on the size of the
circuit that expresses the functionality to be computed and hence can be
impractical. Hence special solutions are needed for specific problems for
efficiency reasons. The point inclusion problem in computational geometry is a
special multiparty computation and has got many applications. Previous
protocols for the secure point inclusion problem are not adequate. In this
paper we modify some known solutions to the point inclusion problem in
computational geometry to the frame work of secure two-party computation.


title:
(Anti)symmetric multivariate trigonometric functions and corresponding
  Fourier transforms

abstract:
  Four families of special functions, depending on n variables, are studied. We
call them symmetric and antisymmetric multivariate sine and cosine functions.
They are given as determinants or antideterminants of matrices, whose matrix
elements are sine or cosine functions of one variable each. These functions are
eigenfunctions of the Laplace operator, satisfying specific conditions at the
boundary of a certain domain F of the n-dimensional Euclidean space. Discrete
and continuous orthogonality on F of the functions within each family, allows
one to introduce symmetrized and antisymmetrized multivariate Fourier-like
transforms, involving the symmetric and antisymmetric multivariate sine and
cosine functions.


title: On the upper limit of thermal conductivity GaN crystals

abstract:
  The maximal value of thermal conductivity \kappa_{max} of the perfect wurzite
GaN crystal containing isotopes of natural abundance is estimated. Our upper
limit of \kappa=4800 W/Km at T_{max}=32 K is smaller than calculated by Liu and
Balandin \kappa=6000 W/Km and higher than obtained by Slack et al \kappa=3750
W/Km. The phenomenological dependence \kappa \propto T^{-1.43} obtained by Mion
et al for the temperature interval 300-450 K is extended to 200-300K. For
temperatures higher than T_max the best fitting of our experimental data to
Callaway's formula is obtained for Grueneisen's constant equal to \gamma =
1.35.


title: On non-Markovian time evolution in open quantum systems

abstract:
  Non-Markovian reduced dynamics of an open system is investigated. In the case
the initial state of the reservoir is the vacuum state, an approximation is
introduced which makes possible to construct a reduced dynamics which is
completely positive.


title:
Yukawa potentials in systems with partial periodic boundary conditions
  II : Lekner sums for quasi-two dimensional systems

abstract:
  Yukawa potentials may be long ranged when the Debye screening length is
large. In computer simulations, such long ranged potentials have to be taken
into account with convenient algorithms to avoid systematic bias in the
sampling of the phase space. Recently, we have provided Ewald sums for
quasi-two dimensional systems with Yukawa interaction potentials [M. Mazars,
{\it J. Chem. Phys.}, {\bf 126}, 056101 (2007) and M. Mazars, {\it Mol. Phys.},
Paper I]. Sometimes, Lekner sums are used as an alternative to Ewald sums for
Coulomb systems. In the present work, we derive the Lekner sums for quasi-two
dimensional systems with Yukawa interaction potentials and we give some
numerical tests for pratical implementations. The main result of this paper is
to outline that Lekner sums cannot be considered as an alternative to Ewald
sums for Yukawa potentials. As a conclusion to this work : Lekner sums should
not be used for quasi-two dimensional systems with Yukawa interaction
potentials.


title: Closed geodesics on positively curved Finsler spheres

abstract:
  In this paper, we prove that for every Finsler $n$-sphere $(S^n, F)$ for
$n\ge 3$ with reversibility $\lambda$ and flag curvature $K$ satisfying
$(\frac{\lambda}{\lambda+1})^2<K\le 1$, either there exist infinitely many
prime closed geodesics or there exists one elliptic closed geodesic whose
linearized Poincar\'e map has at least one eigenvalue which is of the form
$\exp(\pi i \mu)$ with an irrational $\mu$. Furthermore, there always exist
three prime closed geodesics on any $(S^3, F)$ satisfying the above pinching
condition.


title:
Resonant scattering of spin waves from a region of inhomogeneous
  magnetic field in a ferromagnetic film

abstract:
  The transmission of a dipole-dominated spin wave in a ferromagnetic film
through a localised inhomogeneity in the form of a magnetic field produced by a
dc current through a wire placed on the film surface was studied experimentally
and theoretically. It was shown that the amplitude and phase of the transmitted
wave can be simultaneously affected by the current induced field, a feature
that will be relevant for logic based on spin wave transport.
  The direction of the current creates either a barrier or well for spin wave
transmission. The main observation is that the current dependence of the
amplitude of the spin wave transmitted through the well inhomogeneity is
non-monotonic. The dependence has a minimum and an additional maximum. A theory
was constructed to clarify the nature of the maximum. It shows that the
transmission of spin waves through the inhomogeneity can be considered as a
scattering process and that the additional maximum is a scattering resonance.


title:
Separated before birth: pulsars B2020+28 and B2021+51 as the remnants of
  runaway stars

abstract:
  Astrometric data on the pulsars B2020+28 and B2021+51 suggest that they
originated within several parsecs of each other in the direction of the Cyg OB2
association. It was proposed that the pulsars share their origin in a common
massive binary and were separated at the birth of the second pulsar following
the asymmetric supernova explosion. We consider a different scenario for the
origin of the pulsar pair based on a possibility that the pulsars were
separated before their birth and that they are the remnants of runaway stars
ejected (with velocities similar to those of the pulsars) from the core of Cyg
OB2 due to strong three- or four-body dynamical encounters. Our scenario does
not require any asymmetry in supernova explosions.


title: Lecture notes on Optical Quantum Computing

abstract:
  A quantum computer is a machine that can perform certain calculations much
faster than a classical computer by using the laws of quantum mechanics.
Quantum computers do not exist yet, because it is extremely difficult to
control quantum mechanical systems to the necessary degree. What is more, we do
at this moment not know which physical system is the best suited for making a
quantum computer (although we have some ideas). It is likely that a mature
quantum information processing technology will use (among others) light,
because photons are ideal carriers for quantum information. These notes are an
expanded version of the five lectures I gave on the possibility of making a
quantum computer using light, at the Summer School in Theoretical Physics in
Durban, 14-24 January, 2007. There are quite a few proposals using light for
quantum computing, and I can highlight only a few here. I will focus on
photonic qubits, and leave out continuous variables completely. I assume that
the reader is familiar with basic quantum mechanics and introductory quantum
computing.


title: Rational BV-algebra in String Topology

abstract:
  Let $M$ be a 1-connected closed manifold and $LM$ be the space of free loops
on $M$. In \cite{C-S} M. Chas and D. Sullivan defined a structure of BV-algebra
on the singular homology of $LM$, $H_\ast(LM; \bk)$. When the field of
coefficients is of characteristic zero, we prove that there exists a BV-algebra
structure on $\hH^\ast(C^\ast (M); C^\ast (M))$ which carries the canonical
structure of Gerstenhaber algebra. We construct then an isomorphism of
BV-algebras between $\hH^\ast (C^\ast (M); C^\ast (M)) $ and the shifted $
H_{\ast+m} (LM; {\bk})$. We also prove that the Chas-Sullivan product and the
BV-operator behave well with the Hodge decomposition of $H_\ast (LM) $.


title:
VSOP: The Variable Star One-shot Project I. Project presentation and
  first data release

abstract:
  The Variable Star One-shot Project (VSOP) is aimed at (1) providing the
variability type and spectral type of all unstudied variable stars, (2)
process, publish, and make the data available as automatically as possible, and
(3) generate serendipitous discoveries. This first paper describes the project
itself, the acquisition of the data, the dataflow, the spectroscopic analysis
and the on-line availability of the fully calibrated and reduced data. We also
present the results on the 221 stars observed during the first semester of the
project. We used the high-resolution echelle spectrographs HARPS and FEROS in
the ESO La Silla Observatory (Chile) to survey known variable stars. Once
reduced by the dedicated pipelines, the radial velocities are determined from
cross correlation with synthetic template spectra, and the spectral types are
determined by an automatic minimum distance matching to synthetic spectra, with
traditional manual spectral typing cross-checks. The variability types are
determined by manually evaluating the available light curves and the
spectroscopy. In the future, a new automatic classifier, currently being
developed by members of the VSOP team, based on these spectroscopic data and on
the photometric classifier developed for the COROT and Gaia space missions,
will be used. We confirm or revise spectral types of 221 variable stars from
the GCVS. We identify 26 previously unknown multiple systems, among them
several visual binaries with spectroscopic binary individual components. We
present new individual results for the multiple systems V349 Vel and BC Gru,
for the composite spectrum star V4385 Sgr, for the T-Tauri star V1045 Sco, and
for DM Boo which we re-classify as a BY Draconis variable. The complete data
release can be accessed via the VSOP web site.


title: The AU Microscopii Debris Disk: Multiwavelength Imaging and Modeling

abstract:
  (abridged) Debris disks around main sequence stars are produced by the
erosion and evaporation of unseen parent bodies. AU Microscopii (GJ 803) is a
compelling object to study in the context of disk evolution across different
spectral types, as it is an M dwarf whose near edge-on disk may be directly
compared to that of its A5V sibling beta Pic. We resolve the disk from 8-60 AU
in the near-IR JHK' bands at high resolution with the Keck II telescope and
adaptive optics, and develop a novel data reduction technique for the removal
of the stellar point spread function. The point source detection sensitivity in
the disk midplane is more than a magnitude less sensitive than regions away
from the disk for some radii. We measure a blue color across the near-IR bands,
and confirm the presence of substructure in the inner disk. Some of the
structural features exhibit wavelength-dependent positions. The disk
architecture and characteristics of grain composition are inferred through
modeling. We approach the modeling of the dust distribution in a manner that
complements previous work. Using a Monte Carlo radiative transfer code, we
compare a relatively simple model of the distribution of porous grains to a
broad data set, simultaneously fitting to midplane surface brightness profiles
and the spectral energy distribution. Our model confirms that the large-scale
architecture of the disk is consistent with detailed models of steady-state
grain dynamics. Here, a belt of parent bodies from 35-40 AU is responsible for
producing dust that is then swept outward by the stellar wind and radiation
pressures. We infer the presence of very small grains in the outer region, down
to sizes of ~0.05 micron. These sizes are consistent with stellar mass-loss
rates Mdot_* << 10^2 Mdot_sun.


title: Spectrum and multiplier ideals of arbitrary subvarieties

abstract:
  We introduce a spectrum for arbitrary varieties. This generalizes the
definition by Steenbrink for hypersurfaces. In the isolated complete
intersection singularity case, it coincides with the one given by Ebeling and
Steenbrink except for the coefficients of integral exponents. We show a
relation to the graded pieces of the multiplier ideals by using a relation to
the filtration $V$ of Kashiwara and Malgrange. This implies a partial
generalization of a theorem of Budur in the hypersurface case. The point is to
consider the direct sum of the graded pieces of the multiplier ideals as a
module over the algebra defining the normal cone of the subvariety. We also
give a combinatorial description in the case of monomial ideals.


title:
Exotic Mott phases of the extended t--J model on the checkerboard
  lattice at commensurate densities

abstract:
  Coulomb repulsion between electrons moving on a frustrated lattice can give
rise, at simple commensurate electronic densities, to exotic insulating phases
of matter. Such a phenomenon is illustrated using an extended t--J model on a
planar pyrochlore lattice for which the work on the quarter-filled case
[cond-mat/0702367] is complemented and extended to 1/8- and 3/8-fillings. The
location of the metal-insulator transition as a function of the Coulomb
repulsion is shown to depend strongly on the sign of the hopping. Quite
generally, the metal-insulator transition is characterized by lattice symmetry
breaking but the nature of the insulating Mott state is more complex than a
simple Charge Density Wave. Indeed, in the limit of large Coulomb repulsion,
the physics can be described in the framework of (extended) quantum
fully-packed loop or dimer models carrying extra spin degrees of freedom.
Various diagonal and off-diagonal plaquette correlation functions are computed
and the low-energy spectra are analyzed in details in order to characterize the
nature of the insulating phases. We provide evidence that, as for an electronic
density of n=1/2 (quarter-filling), the system at $n=1/4$ or $n=3/4$ exhibits
also plaquette order by forming a (lattice rotationally-invariant)
Resonating-Singlet-Pair Crystal, although with a quadrupling of the lattice
unit cell (instead of a doubling for $n=1/2$) and a 4-fold degenerate ground
state. Interestingly, qualitative differences with the bosonic analog (e.g.
known to exhibit columnar order at n=1/4) emphasize the important role of the
spin degrees of freedom in e.g. stabilizing plaquette phases w.r.t. rotational
symmetry-breaking phases.


title:
In search of an unbiased temperature estimator for statistically poor
  X-ray spectra

abstract:
  Although commonly employed by X-ray astronomers, maximum likelihood
estimators are known to be biased. In this paper we investigate the bias
associated to the measure of the temperature from an X-ray thermal spectrum. We
show that, in the case of low surface brightness regions, commonly adopted
estimators, such as those based on chi squared and Cash statistics, return
strongly biased results. We stress that this can have strong implications when
measuring the temperature of cluster outer regions with current experiments. We
consider various approaches to overcome this problem, the most effective is a
technique which allows us to correct the bias a posteriori. Extensive
montecarlo simulations show that our correction returns excellent results under
different conditions.


title: A mean value theorem for systems of integrals

abstract:
  More than a century ago, G. Kowalewski stated that for each n continuous
functions on a compact interval [a,b], there exists an n-point quadrature rule
(with respect to Lebesgue measure on [a,b]), which is exact for given
functions. Here we generalize this result to continuous functions with an
arbitrary positive and finite measure on an arbitrary interval. The proof
relies on a version of Caratheodory's convex hull theorem for a continuous
curve, that we also prove in the paper. As applications, we give a
representation of the covariance for two continuous functions of a random
variable, and a most general version of Gruess' inequality.


title: On residual properties of pure braid groups of closed surfaces

abstract:
  We prove that pure braid groups of closed surface are almost-direct products
of residually torsion free nilpotent groups and hence residually torsion free
nilpotent. As a Corollary, we prove also that braid groups on 2 strands of
closed surfaces are residually nilpotent.


title:
Higher Dimensional Strange Quark Matter Coupled to the String Cloud with
  Electromagnetic Field Admitting One Parameter Group of Conformal Motion

abstract:
  This paper has been withdrawn by arXiv administrators because of an
inappropriate amount of overlap with hep-th/0505013.


title: Dynamical Diophantine Approximation

abstract:
  Let $\mu$ be a Gibbs measure of the doubling map $T$ of the circle. For a
$\mu$-generic point $x$ and a given sequence $\{r_n\} \subset \R^+$, consider
the intervals $(T^nx - r_n \pmod 1, T^nx + r_n \pmod 1)$. In analogy to the
classical Dvoretzky covering of the circle we study the covering properties of
this sequence of intervals. This study is closely related to the local entropy
function of the Gibbs measure and to hitting times for moving targets. A mass
transference principle is obtained for Gibbs measures which are multifractal.
Such a principle was shown by Beresnevich and Velani \cite{BV} only for
monofractal measures. In the symbolic language we completely describe the
combinatorial structure of a typical relatively short sequence, in particular
we can describe the occurrence of ''atypical'' relatively long words. Our
results have a direct and deep number-theoretical interpretation via
inhomogeneous diadic diophantine approximation by numbers belonging to a given
(diadic) diophantine class.


title: Shot noise in non-adiabatically driven nanoscale conductors

abstract:
  We investigate the noise properties of pump currents through molecular wires
and coupled quantum dots. As a model we employ a two level system that is
connected to electron reservoirs and is non-adiabatically driven. Concerning
the electron-electron interaction, we focus on two limits: non-interacting
electrons and strong Coulomb repulsion. While the former case is treated within
a Floquet scattering formalism, we derive for the latter case a master equation
formalism for the computation of the current and the zero-frequency noise. For
a pump operated close to internal resonances, the differences between the
non-interacting and the strongly interacting limit turn out to be surprisingly
small.


title:
Non-Commutative U(1) Gauge Theory on R**4 with Oscillator Term and BRST
  Symmetry

abstract:
  Inspired by the renormalizability of the non-commutative Phi^4 model with
added oscillator term, we formulate a non-commutative gauge theory, where the
oscillator enters as a gauge fixing term in a BRST invariant manner. All
propagators turn out to be essentially given by the Mehler kernel and the
bilinear part of the action is invariant under the Langmann-Szabo duality. The
model is a promising candidate for a renormalizable non-commutative U(1) gauge
theory.


title: Multiple Volume Reflection from Different Planes Inside One Bent Crystal

abstract:
  It is shown that multiple volume reflections from different planes of one
bent crystal becomes possible when particles move at a small angle with respect
to a crystal axis. Such a Multiple Volume Reflection makes it possible to
increase the particle deflection angle inside one crystal by more than four
times and can be used to increase the efficiency of beam extraction and
collimation at the LHC and many other accelerators.


title:
Measurement of the Spin-Transfer-Torque Vector in Magnetic Tunnel
  Junctions

abstract:
  Spin-polarized currents can transfer spin angular momentum to a ferromagnet,
generating a torque that can efficiently reorient its magnetization. Achieving
quantitative measurements of the spin-transfer-torque vector in magnetic tunnel
junctions (MTJs) is important for understanding fundamental mechanisms
affecting spin-dependent tunneling, and for developing magnetic memories and
nanoscale microwave oscillators. Here we present direct measurements of both
the magnitude and direction of the spin torque in Co60Fe20B20/MgO/Co60Fe20B20
MTJs. At low bias V, the differential torque vector d{tau}/dV lies in the plane
defined by the electrode magnetizations, and its magnitude is in excellent
agreement with a prediction for highly-spin-polarized tunneling. With
increasing bias, the in-plane component d{tau}_{parallel}/dV remains large, in
striking contrast to the decreasing magnetoresistance ratio. The differential
torque vector also rotates out of the plane under bias; we measure a
perpendicular component tau_{perp}(V) with bias dependence proportional to V^2
for low V, that becomes as large as 30% of the in-plane torque.


title: Ratliff-Rush Closure of Ideals in Integral Domains

abstract:
  This paper studies the Ratliff-Rush closure of ideals in integral domains. By
definition, the Ratliff-Rush closure of an ideal $I$ of a domain $R$ is the
ideal given by $\tilde{I}:=\bigcup(I^{n+1}:_{R}I^{n})$ and an ideal $I$ is said
to be a Ratliff-Rush ideal if $\tilde{I}=I$. We completely characterize
integrally closed domains in which every ideal is a Ratliff-Rush ideal and we
give a complete description of the Ratliff-Rush closure of an ideal in a
valuation domain.


title: On Infinite EPR-like Correlations

abstract:
  The paper investigates, in the framework of branching space-times, whether an
infinite EPR-like correlation which does not involve finite EPR-like
correlations is possible.


title: Spontaneous Breakdown of Superhydrophobicity

abstract:
  In some cases water droplets can completely wet micro-structured
superhydrophobic surfaces. The {\it dynamics} of this rapid process is analyzed
by ultra-high-speed imaging. Depending on the scales of the micro-structure,
the wetting fronts propagate smoothly and circularly or -- more interestingly
-- in a {\it stepwise} manner, leading to a growing {\it square-shaped} wetted
area: entering a new row perpendicular to the direction of front propagation
takes milliseconds, whereas once this has happened, the row itself fills in
microseconds ({\it ``zipping''})

categories: physics.flu-dyn cond-mat.soft cond-mat.stat-mech nlin.PS


title:
Multiple scattering and energy loss in semi-inclusive deeply inelastic
  eA scattering

abstract:
  We calculate the multiple scattering effect on single hadron production in
semi-inclusive lepton-nucleus deeply inelastic scattering. We show that the
quantum interference of multiple scattering amplitudes leads to suppression in
hadron productions. At the leading power in medium length, the suppression can
be approximately expressed in terms of a shift in $z$ of the fragmentation
function $D(z)$, and could be therefore interpreted as the collisional energy
loss. We compare our calculation with existing experimental data. We also
discuss the effect of quark mass on the suppression. Our approach can be
extended to other observables in hadronic collisions.


title:
Surface plasmon polaritons and surface phonon polaritons on metallic and
  semiconducting spheres: Exact and semiclassical descriptions

abstract:
  We study the interaction of an electromagnetic field with a non-absorbing or
absorbing dispersive sphere in the framework of complex angular momentum
techniques. We assume that the dielectric function of the sphere presents a
Drude-like behavior or an ionic crystal behavior modelling metallic and
semiconducting materials. We more particularly emphasize and interpret the
modifications induced in the resonance spectrum by absorption. We prove that
"resonant surface polariton modes" are generated by a unique surface wave,
i.e., a surface (plasmon or phonon) polariton, propagating close to the sphere
surface. This surface polariton corresponds to a particular Regge pole of the
electric part (TM) of the S matrix of the sphere. From the associated Regge
trajectory we can construct semiclassically the spectrum of the complex
frequencies of the resonant surface polariton modes which can be considered as
Breit-Wigner-type resonances. Furthermore, by taking into account the Stokes
phenomenon, we derive an asymptotic expression for the position in the complex
angular momentum plane of the surface polariton Regge pole. We then describe
semiclassically the surface polariton and provide analytical expressions for
its dispersion relation and its damping in the non-absorbing and absorbing
cases. In these analytic expressions, we more particularly exhibit
well-isolated terms directly linked to absorption. Finally, we explain why the
photon-sphere system can be considered as an artificial atom (a ``plasmonic
atom" or "phononic atom") and we briefly discuss the implication of our results
in the context of the Casimir effect.


title: Geometric Weil representation: local field case

abstract:
  Let k be an algebraically closed field of characteristic >2, F=k((t)) and
Mp(F) denote the metaplectic extension of Sp_{2d}(F). In this paper we propose
a geometric analog of the Weil representation of Mp(F). This is a category of
certain perverse sheaves on some stack, on which Mp(F) acts by functors. This
construction will be used in math.RT/0701170 (and subsequent publications) for
a proof of the geometric Langlands functoriality for some dual reductive pairs.


title: Near-horizon symmetries of extremal black holes

abstract:
  Recent work has demonstrated an attractor mechanism for extremal rotating
black holes subject to the assumption of a near-horizon SO(2,1) symmetry. We
prove the existence of this symmetry for any extremal black hole with the same
number of rotational symmetries as known four and five dimensional solutions
(including black rings). The result is valid for a general two-derivative
theory of gravity coupled to abelian vectors and uncharged scalars, allowing
for a non-trivial scalar potential. We prove that it remains valid in the
presence of higher-derivative corrections. We show that SO(2,1)-symmetric
near-horizon solutions can be analytically continued to give SU(2)-symmetric
black hole solutions. For example, the near-horizon limit of an extremal 5D
Myers-Perry black hole is related by analytic continuation to a non-extremal
cohomogeneity-1 Myers-Perry solution.


title:
Non local Andreev reflection in a carbon nanotube superconducting
  quantum interference device

abstract:
  We investigate a superconducting quantum interference device (SQUID) based on
carbon nanotubes in a fork geometry [J.-P. Cleuziou {\it et al.}, Nature
Nanotechnology {\bf 1}, 53 (2006)], involving tunneling of evanescent
quasiparticles through a superconductor over a distance comparable to the
superconducting coherence length, with therefore ``non local'' processes
generalizing non local Andreev reflection and elastic cotunneling. Non local
processes induce a reduction of the critical current and modify the
current-phase relation. We discuss arbitrary interface transparencies. Such
devices in fork geometries are candidates for probing the phase coherence of
crossed Andreev reflection.


title:
Symplectic structure of N=1 supergravity with anomalies and Chern-Simons
  terms

abstract:
  The general actions of matter-coupled N=1 supergravity have Peccei-Quinn
terms that may violate gauge and supersymmetry invariance. In addition, N=1
supergravity with vector multiplets may also contain generalized Chern-Simons
terms. These have often been neglected in the literature despite their
importance for gauge and supersymmetry invariance. We clarify the interplay of
Peccei-Quinn terms, generalized Chern-Simons terms and quantum anomalies in the
context of N=1 supergravity and exhibit conditions that have to be satisfied
for their mutual consistency. This extension of the previously known N=1
matter-coupled supergravity actions follows naturally from the embedding of the
gauge group into the group of symplectic duality transformations. Our results
regarding this extension provide the supersymmetric framework for studies of
string compactifications with axionic shift symmetries, generalized
Chern-Simons terms and quantum anomalies.


title:
Local tunneling spectroscopy of the electron-doped cuprate
  Sm1.85Ce0.15CuO4

abstract:
  We present local tunneling spectroscopy in the optimally electron-doped
cuprate Sm2-xCexCuO4 x=0.15. A clear signature of the superconducting gap is
observed with an amplitude ranging from place to place and from sample to
sample (Delta~3.5-6meV). Another spectroscopic feature is simultaneously
observed at high energy above \pm 50meV. Its energy scale and temperature
evolution is found to be compatible with previous photoemission and optical
experiments. If interpreted as the signature of antiferromagnetic order in the
samples, these results could suggest the coexistence on the local scale of
antiferromagnetism and superconductivity on the electron-doped side of cuprate
superconductors.


title:
$PT$ symmetric non-selfadjoint operators, diagonalizable and
  non-diagonalizable, with real discrete spectrum

abstract:
  Consider in $L^2(R^d)$, $d\geq 1$, the operator family $H(g):=H_0+igW$. $\ds
H_0= a^\ast_1a_1+... +a^\ast_da_d+d/2$ is the quantum harmonic oscillator with
rational frequencies, $W$ a $P$ symmetric bounded potential, and $g$ a real
coupling constant. We show that if $|g|<\rho$, $\rho$ being an explicitly
determined constant, the spectrum of $H(g)$ is real and discrete. Moreover we
show that the operator $\ds H(g)=a^\ast_1 a_1+a^\ast_2a_2+ig a^\ast_2a_1$ has
real discrete spectrum but is not diagonalizable.


title: Natural Dark Matter in SUSY GUTs with Non-universal Gaugino Masses

abstract:
  We consider neutralino dark matter within the framework of SUSY GUTs with
non-universal gaugino masses. In particular we focus on the case of SU(5) with
a SUSY breaking F-term in the 1, 24, 75 and 200 dimensional representations. We
discuss the 24 case in some detail, and show that the bulk dark matter region
cannot be accessed. We then go on to consider the admixture of the singlet SUSY
breaking F-term with one of the 24, 75 or 200 dimensional F-terms, and show
that in these cases it becomes possible to access the bulk regions
corresponding to low fine-tuned dark matter. Our results are presented in the
$(M_1,M_2)$ plane for fixed $M_3$ and so are useful for considering general GUT
models, as well as more general non-universal gaugino models.


title: An Isoperimetric Function for Bestvina-Brady Groups

abstract:
  Given a right-angled Artin group A, the associated Bestvina-Brady group is
defined to be the kernel of the homomorphism A \to \mathbb{Z} that maps each
generator in the standard presentation of A to a fixed generator of \mathbb{Z}.
We prove that the Dehn function of an arbitrary finitely presented
Bestvina-Brady group is bounded above by n^4. This is the best possible
universal upper bound.


title:
Controllability of the heat and wave equations and their finite
  difference approximations by the shape of the domain

abstract:
  In this article we study a controllability problem for a parabolic and a
hyperbolic partial differential equations in which the control is the shape of
the domain where the equation holds. The quantity to be controlled is the trace
of the solution into an open subdomain and at a given time, when the right hand
side source term is known. The mapping that associates this trace to the shape
of the domain is nonlinear. We show (i) an approximate controllability property
for the linearized parabolic problem and (ii) an exact local controllability
property for the linearized and the nonlinear equations in the hyperbolic case.
We then address the same questions in the context of a finite difference
spatial semi-discretization in both the parabolic and hyperbolic problems. In
this discretized case again we prove a local controllability result for the
parabolic problem, and an exact controllability for the hyperbolic case,
applying a local surjectivity theorem together with a unique continuation
property of the underlying adjoint discrete system.


title: Stochastic Resonance with a Single Metastable State

abstract:
  We study thermal instability in NbN superconducting stripline resonators. The
system exhibits extreme nonlinearity near a bifurcation, which separates a
monostable zone and an astable one. The lifetime of the metastable state, which
is locally stable in the monostable zone, is measure near the bifurcation and
the results are compared with a theory. Near bifurcation, where the lifetime
becomes relatively short, the system exhibits strong amplification of a weak
input modulation signal. We find that the frequency bandwidth of this
amplification mechanism is limited by the rate of thermal relaxation. When the
frequency of the input modulation signal becomes comparable or larger than this
rate the response of the system exhibits sub-harmonics of various orders.


title: Predictions for Triple Stars with and without a Pulsar in Star Clusters

abstract:
  Though about 80 pulsar binaries have been detected in globular clusters so
far, no pulsar has been found in a triple system in which all three objects are
of comparable mass. Here we present predictions for the abundance of such
triple systems, and for the most likely characteristics of these systems. Our
predictions are based on an extensive set of more than 500 direct simulations
of star clusters with primordial binaries, and a number of additional runs
containing primordial triples. Our simulations employ a number N_{tot} of equal
mass stars from N_{tot}=512 to N_{tot}=19661 and a primordial binary fraction
from 0-50%. In addition, we validate our results against simulations with
N=19661 that include a mass spectrum with a turn-off mass at 0.8 M_{sun},
appropriate to describe the old stellar populations of galactic globular
clusters. Based on our simulations, we expect that typical triple abundances in
the core of a dense cluster are two orders of magnitude lower than the binary
abundances, which in itself already suggests that we don't have to wait too
long for the first comparable-mass triple with a pulsar to be detected.


title: Non-relativistic Quantum Mechanics versus Quantum Field Theories

abstract:
  We briefly review the derivation of a non-relativistic quantum mechanics
description of a weakly bound non-relativistic system from the underlying
quantum field theory. We highlight the main techniques used.


title:
How to detect a possible correlation from the information of a
  sub-system in quantum mechanical systems

abstract:
  A possibility to detect correlations between two quantum mechanical systems
only from the information of a subsystem is investigated. For generic cases, we
prove that there exist correlations between two quantum systems if the
time-derivative of the reduced purity is not zero. Therefore, an
experimentalist can conclude non-zero correlations between his/her system and
some environment if he/she finds the time-derivative of the reduced purity is
not zero. A quantitative estimation of a time-derivative of the reduced purity
with respect to correlations is also given. This clarifies the role of
correlations in the mechanism of decoherence in open quantum systems.


title: Second-Order Type Isomorphisms Through Game Semantics

abstract:
  The characterization of second-order type isomorphisms is a purely
syntactical problem that we propose to study under the enlightenment of game
semantics. We study this question in the case of second-order
λ$\mu$-calculus, which can be seen as an extension of system F to
classical logic, and for which we deﬁne a categorical framework: control
hyperdoctrines. Our game model of λ$\mu$-calculus is based on polymorphic
arenas (closely related to Hughes' hyperforests) which evolve during the play
(following the ideas of Murawski-Ong). We show that type isomorphisms coincide
with the "equality" on arenas associated with types. Finally we deduce the
equational characterization of type isomorphisms from this equality. We also
recover from the same model Roberto Di Cosmo's characterization of type
isomorphisms for system F. This approach leads to a geometrical comprehension
on the question of second order type isomorphisms, which can be easily extended
to some other polymorphic calculi including additional programming features.


title: Brane Cosmology and KK Gravitinos

abstract:
  The cosmology of KK gravitinos in models with extra dimensions is considered.
The main result is that the production of such KK modes is not compatible with
an epoch of non--standard expansion after inflation. This is so because the BBN
constraint on the zero mode forces the reduced five dimensional Planck mass
$M_5$ down to values much smaller than the usual four dimensional one, but this
in turn implies many KK states available for a given temperature. Once these
states are taken into account one finds that there is no $M_5$ for which the
produced KK gravitinos satisfy BBN and overclosure constraints. This conclusion
holds for both flat and warped models in which only gravity propagates in the
full spacetime.


title: Curry-style type Isomorphisms and Game Semantics

abstract:
  Curry-style system F, ie. system F with no explicit types in terms, can be
seen as a core presentation of polymorphism from the point of view of
programming languages. This paper gives a characterisation of type isomorphisms
for this language, by using a game model whose intuitions come both from the
syntax and from the game semantics universe. The model is composed of: an
untyped part to interpret terms, a notion of game to interpret types, and a
typed part to express the fact that an untyped strategy plays on a game. By
analysing isomorphisms in the model, we prove that the equational system
corresponding to type isomorphisms for Curry-style system F is the extension of
the equational system for Church-style isomorphisms with a new, non-trivial
equation: forall X.A = A[forall Y.Y/X] if X appears only positively in A.


title:
Superconducting MgB2 thin films nano-bridges for cryo-electronic
  application

abstract:
  Precursor MgB2 thin films were prepared on sapphire substrates by magnetron
sputtering. Influence of ex-situ annealing process on superconducting MgB2 thin
films roughness is discussed. Optimized annealing process of MgB precursor thin
films in vacuum results in smooth superconducting MgB2 thin films with
roughness below 10 nm, critical temperature Tcon = 31 K and transition width
DTc less than 1 K. Nano-bridges based on the superconducting MgB2 thin films
using optical and Focused Ion Beam lithography were prepared. Critical current
density jc (4.2 K) measured on 50 nm wide strip was 7.3x106 A/cm2 and no
significant loss of superconducting properties was detected. Resistance vs.
temperature and critical current vs. temperature characteristics were measured
on these structures using standard DC four probe measurements.


title: Efficient independent component analysis

abstract:
  Independent component analysis (ICA) has been widely used for blind source
separation in many fields such as brain imaging analysis, signal processing and
telecommunication. Many statistical techniques based on M-estimates have been
proposed for estimating the mixing matrix. Recently, several nonparametric
methods have been developed, but in-depth analysis of asymptotic efficiency has
not been available. We analyze ICA using semiparametric theories and propose a
straightforward estimate based on the efficient score function by using
B-spline approximations. The estimate is asymptotically efficient under
moderate conditions and exhibits better performance than standard ICA methods
in a variety of simulations.


title: Parametric spin excitations in lateral quantum dots

abstract:
  In this work, the spin dynamics of a single electron under parametric
modulation of a lateral quantum dot's electrostatic potential in the presence
of spin-orbit coupling is investigated. Numerical and theoretical calculations
demonstrate that, by squeezing and/or moving the electron's wave function, spin
rotations with Rabi frequencies on the order of tens of megahertz can be
achieved with experimentally accessible parameters in both parabolic and square
lateral quantum dots. Applications of parametric excitations for determining
spin-orbit coupling parameters and for increasing the spin polarization in the
electronic ground are demonstrated.


title: First observation of (anti)deuterons in DIS

abstract:
  First observation of (anti)deuterons in deep inelastic ep scattering (DIS)
measured with the ZEUS detector at HERA is reported. The production rate of
deuterons is higher than that of antideuterons. However, no asymmetry in the
production rate of protons and antiprotons was found. The (anti)deuteron yield
is approximately three orders of magnitude smaller than that of (anti)protons,
which is consistent with the world measurements.


title: Effect of magnetic field on spontaneous Fermi surface symmetry breaking

abstract:
  We study magnetic field effects on spontaneous Fermi surface symmetry
breaking with d-wave symmetry, the so-called d-wave "Pomeranchuk instability''.
We use a mean-field model of electrons with a pure forward scattering
interaction on a square lattice. When either the majority or the minority spin
band is tuned close to the van Hove filling by a magnetic field, the Fermi
surface symmetry breaking occurs in both bands, but with a different magnitude
of the order parameter. The transition is typically of second order at high
temperature and changes to first order at low temperature; the end points of
the second order line are tricritical points. This qualitative picture does not
change even in the limit of a large magnetic field, although the magnetic field
substantially suppresses the transition temperature at the van Hove filling.
The field produces neither a quantum critical point nor a quantum critical end
point in our model. In the weak coupling limit, typical quantities
characterizing the phase diagram have a field-independent single energy scale
while its dimensionless coefficient varies with the field. The field-induced
Fermi surface symmetry breaking is a promising scenario for the bilayer
ruthenate Sr3Ru2O7, and future issues are discussed to establish such a
scenario.


title:
A Study on anisotropy of cosmic ray distribution with a small array of
  water-cherenkov detectors

abstract:
  The study of the anisotropy of the arrival directions is an essential tool to
investigate the origin and propagation of cosmic rays primaries. A simple way
of recording many cosmic rays is to record coincidences between a number of
detectors. We have monitored multi-TeV cosmic rays by a small array of water
cherenkov detectors in Tehran(35 43 N, 51 20 E, 1200m a.s.l). More than
1.1*10^6 extensive air shower events were recorded. In addition to the Compton-
Getting effect due to the motion of the earth in the Galaxy, an anisotropy has
been observed which is due to a unidirectional anisotropy of cosmic ray flow
along the Galactic arms.


title: Spin evolution of spin-1 Bose-Einstein condensates

abstract:
  An analytical formula is obtained to describe the evolution of the average
populations of spin components of spin-1 atomic gases. The formula is derived
from the exact time-dependent solution of the Hamiltonian $H_{S}=c
mathbf{S}^{2}$ without using approximation. Therefore it goes beyond the mean
field theory and provides a general, accurate, and complete description for the
whole process of non-dissipative evolution starting from various initial
states. The numerical results directly given by the formula coincide
qualitatively well with existing experimental data, and also with other
theoretical results from solving dynamic differential equations. For some
special cases of initial state, instead of undergoing strong oscillation as
found previously, the evolution is found to go on very steadily in a very long
duration.


title: A survey of hypertoric geometry and topology

abstract:
  Hypertoric varieties are quaternionic analogues of toric varieties, important
for their interaction with the combinatorics of matroids as well as for their
prominent place in the rapidly expanding field of algebraic symplectic and
hyperkahler geometry. The aim of this survey is to give clear definitions and
statements of known results, serving both as a reference and as a point of
entry to this beautiful subject.


title: Stability of viscous shocks in isentropic gas dynamics

abstract:
  In this paper, we examine the stability problem for viscous shock solutions
of the isentropic compressible Navier--Stokes equations, or $p$-system with
real viscosity. We first revisit the work of Matsumura and Nishihara, extending
the known parameter regime for which small-amplitude viscous shocks are
provably spectrally stable by an optimized version of their original argument.
Next, using a novel spectral energy estimate, we show that there are no purely
real unstable eigenvalues for any shock strength.
  By related estimates, we show that unstable eigenvalues are confined to a
bounded region independent of shock strength. Then through an extensive
numerical Evans function study, we show that there is no unstable spectrum in
the entire right-half plane, thus demonstrating numerically that
large-amplitude shocks are spectrally stable up to Mach number $M\approx 3000$
for $1 \le \gamma \leq 3$. This strongly suggests that shocks are stable
independent of amplitude and the adiabatic constant $\gamma$. We complete our
study by showing that finite-difference simulations of perturbed
large-amplitude shocks converge to a translate of the original shock wave, as
expected.


title:
Accurate description of optical precursors and their relation to
  weak-field coherent optical transients

abstract:
  We study theoretically the propagation of a step-modulated optical field as
it passes through a dispersive dielectric made up of a dilute collection of
oscillators characterized by a single narrow-band resonance. The propagated
field is given in terms of an integral of a Fourier type, which cannot be
evaluated even for simple models of the dispersive dielectric. The fact that
the oscillators have a low number density (dilute medium) and have a
narrow-band resonance allows us to simplify the integrand. In this case, the
integral can be evaluated exactly, although it is not possible using this
method to separate out the transient part of the propagated field known as
optical precursors. We also use an asymptotic method (saddle-point method) to
evaluate the integral. The contributions to the integral related to the
saddle-points of the integrand give rise to the optical precursors. We obtain
analytic expressions for the precursor fields and the domain over which the
asymptotic method is valid. When combined to obtain the total transient field,
we find that the agreement between the solutions obtained by the asymptotic and
the exact methods is excellent. Our results demonstrate that precursors can
persist for many nanoseconds and the chirp in the instantaneous frequency of
the precursors can manifest itself in beats in the transmitted intensity. Our
work strongly suggests that precursors have been observed in many previous
experiments.


title:
Global well-posedness of the KP-I initial-value problem in the energy
  space

abstract:
  We prove that the KP-I initial value problem is globally well-posed in the
natural energy space of the equation.


title: The Maximal Amount of Gravitational Waves in the Curvaton Scenario

abstract:
  The curvaton scenario for the generation of the cosmological curvature
perturbation on large scales represents an alternative to the standard
slow-roll scenario of inflation in which the observed density perturbations are
due to fluctuations of the inflaton field itself. Its basic assumption is that
the initial curvature perturbation due to the inflaton field is negligible.
This is attained by lowering the energy scale of inflation, thereby highly
suppressing the amount of gravitational waves produced during inflation. We
compute the power-spectrum of the gravitational waves generated at second order
in perturbation theory by the curvaton (isocurvature) perturbations between the
end of inflation and the curvaton decay. An interesting property of this
contribution to the tensor perturbations is that it is directly proportional to
the amount of non-Gaussianity predicted within the curvaton scenario. We show
that the spectrum of gravitational waves may be in the range of future
gravitational wave detectors.


title: Variation of the hopping exponent in disordered silicon MOSFETs

abstract:
  We observe a complex change in the hopping exponent value from 1/2 to 1/3 as
a function of disorder strength and electron density in a sodium-doped silicon
MOSFET. The disorder was varied by applying a gate voltage and thermally
drifting the ions to different positions in the oxide. The same gate was then
used at low temperature to modify the carrier concentration.
Magnetoconductivity measurements are compatible with a change in transport
mechanisms when either the disorder or the electron density is modified
suggesting a possible transition from a Mott insulator to an Anderson insulator
in these systems.


title:
Oscillation thresholds for "strinking outwards" reeds coupled to a
  resonator

abstract:
  This paper considers a "striking outwards" reed coupled to a resonator. This
expression, due to Helmholtz, is not discussed here : it corresponds to the
most common model of a lip-type valve, when the valve is assumed to be a one
degree of freedom oscillator. The presented work is an extension of the works
done by Wilson and Beavers (1974), Tarnopolsky (2000). The range of the playing
frequencies is investigated. The first results are analytical : when no losses
are present in the resonator, it is proven that the ratio between the threshold
frequency and the reed resonance frequency is found to be necessarily within
the interval between unity and the square root of 3. This is a musical sixth.
Actually the interval is largely smaller, and this is in accordance with e.g.
the results by Cullen et al.. The smallest blowing pressure is found to be
directly related to the quality factor of the reed. Numerical results confirm
these statements, and are discussed in comparison with previous ones by Cullen
et al (2000).