title: The Relative Symplectic Cone and T^2-Fibrations

abstract:
  In this note we introduce the notion of the relative symplectic cone. As an
application, we determine the symplectic cone of certain T^2-fibrations. In
particular, for some elliptic surfaces we verify a conjecture on the symplectic
cone of minimal Kaehler surfaces raised by the second author.


title:
Pairing Symmetry in a Two-Orbital Exchange Coupling Model of
  Oxypnictides

abstract:
  We study the pairing symmetry of a two orbital $J_1-J_2$ model for FeAs
layers in oxypnictides. We vary the doping and the value of $J_1$ and $J_2$ to
compare all possible pairing symmetries in a mean-field calculation. We show
that the mixture of an intra-orbital unconventional $s_{x^2y^2}\sim
\cos(k_x)\cos(k_y)$ pairing symmetry and a $d_{x^2-y^2}\sim
\cos(k_x)-\cos(k_y)$ pairing symmetry is favored in a large part of $J_1-J_2$
phase diagram. A pure $ s_{x^2y^2}$ pairing state is favored for $J_2>>J_1$.
The signs of the $d_{x^2-y^2}$ order parameters in two different orbitals are
opposite. While a small $d_{xy}\sim \sin(k_x)\sin(k_y)$ inter-orbital pairing
order coexists in the above phases, the intra-orbital $d_{xy}$ pairing symmetry
is not favored even for large values of $J_2$.


title:
Nature of the enigmatic pseudogap state: novel magnetic order in
  superconducting HgBa2CuO4+d

abstract:
  The nature of the enigmatic pseudogap region of the phase diagram is the most
important and intriguing unsolved puzzle in the field of high
transition-temperature (Tc) superconductivity. This region, the temperature
range above Tc and below a characteristic temperature T*, is characterized by
highly anomalous magnetic, charge transport, thermodynamic and optical
properties. Associated with the pseudogap puzzle are open questions pertaining
to the number of distinct phases and the presence of a quantum-critical point
underneath the superconducting dome. Here we use polarized neutron diffraction
to demonstrate for the model superconductor HgBa2CuO4+d (Hg1201) that T* marks
the onset of an unusual magnetic order, and hence a novel state of matter with
broken time-reversal symmetry. Together with prior results for YBa2Cu3O6+d
(YBCO), this observation constitutes an essential and decisive demonstration of
the universal existence of such a state. The new findings appear to rule out a
large class of theories that regard T* as a crossover temperature rather than a
phase transition temperature. Instead, they are consistent with a variant of
previously proposed charge-current-loop order that involves apical oxygen
orbitals, and with the notion that many of the unusual properties arise from
the presence of a quantum-critical point.


title: The gravity dual of a p-wave superconductor

abstract:
  We construct black hole solutions to the Yang-Mills equations in an
AdS_4-Schwarzschild background which exhibit superconductivity. What makes
these backgrounds p-wave superconductors is that the order parameter is a
vector, and the conductivities are strongly anisotropic in a manner that is
suggestive of a gap with nodes. The low-lying excitations of the normal state
have a relaxation time which grows rapidly as the temperature decreases,
consistent with the absence of impurity scattering. A numerical exploration of
quasinormal modes close to the transition temperature suggests that p-wave
backgrounds are stable against perturbations analogous to turning on a p+ip
gap, whereas p+ip-wave configurations are unstable against turning into pure
p-wave backgrounds.


title:
Comment on "Why Einstein, Podolsky and Rosen did not prove that quantum
  mechanics is 'incomplete'"

abstract:
  This comment on the recently published article "Why Einstein, Podolsky and
Rosen did not prove that quantum mechanics is 'incomplete'" (arXiv:0805.0217)
by J.H.Field shows that some conclusions, made in the referred-to article,
result from an invalid use of dirac delta-distributions.


title:
A comprehensive comparison of the Sun to other stars: searching for
  self-selection effects

abstract:
  If the origin of life and the evolution of observers on a planet is favoured
by atypical properties of a planet's host star, we would expect our Sun to be
atypical with respect to such properties. The Sun has been described by
previous studies as both typical and atypical. In an effort to reduce this
ambiguity and quantify how typical the Sun is, we identify eleven
maximally-independent properties that have plausible correlations with
habitability, and that have been observed by, or can be derived from,
sufficiently large, currently available and representative stellar surveys. By
comparing solar values for the eleven properties, to the resultant stellar
distributions, we make the most comprehensive comparison of the Sun to other
stars. The two most atypical properties of the Sun are its mass and orbit. The
Sun is more massive than 95 -/+ 2% of nearby stars and its orbit around the
Galaxy is less eccentric than 93 +/- 1% of FGK stars within 40 parsecs. Despite
these apparently atypical properties, a chi^2 -analysis of the Sun's values for
eleven properties, taken together, yields a solar chi^2 = 8.39 +/- 0.96. If a
star is chosen at random, the probability that it will have a lower value (be
more typical) than the Sun, with respect to the eleven properties analysed
here, is only 29 +/- 11%. These values quantify, and are consistent with, the
idea that the Sun is a typical star. If we have sampled all reasonable
properties associated with habitability, our result suggests that there are no
special requirements for a star to host a planet with life.


title: The Adler Kostant Symes scheme in physics

abstract:
  The purpose of this material is to review the Adler Kostant Symes scheme as a
theory which can be developped succesfully in different contexts. It was useful
to describe some mechanical systems, the so called generalized Toda, and now it
was proved to be a tool for the study of the linear approach to the motion of n
uncoupled harmonic oscillators. The complete integrability of these systems has
an algebraic description. In the original theory this is related to
ad-invariant functions, but new examples show that new conditions should be
investigated.


title:
Confinement free energy of flexible polyelectrolytes in spherical
  cavities

abstract:
  A weakly charged flexible polyelectrolyte chain in a neutral spherical cavity
is analyzed using self-consistent field theory (SCFT) within an explicit
solvent model. Assuming the radial symmetry for the system, it is found that
the confinement of the chain leads to creation of a charge density wave along
with the development of a potential difference across the center of cavity and
the surface. We show that the solvent entropy plays an important role in the
free energy of the confined system. For a given radius of the spherical cavity
and fixed charge density along the backbone of the chain, solvent and small ion
entropies dominate over all other contributions when chain lengths are small.
However, with the increase in chain length, chain conformational entropy and
polymer-solvent interaction energy also become important. Our calculations
reveal that energy due to electrostatic interactions plays a minor role in the
free energy. Furthermore, we show that the total free energy under spherical
confinement is not extensive in the number of monomers. Results for the osmotic
pressure and mean activity coefficient for monovalent salt are presented. We
demonstrate that fluctuations at one-loop level lower the free energy and
corrections to the osmotic pressure and mean activity coefficient of the salt
are discussed. Finite size corrections are shown to widen the range of validity
of the fluctuation analysis.


title: The Metallicity of Diffuse Intrahalo Light

abstract:
  We make predictions for the metallicity of diffuse stellar components in
systems ranging from small spiral galaxies to rich galaxy clusters. We extend
the formalism of Purcell et al. (2007), in which diffuse stellar mass is
produced via galaxy disruption, and we convolve this result with the observed
mass-metallicity relation for galaxies in order to analyze the chemical
abundance of intrahalo light (IHL) in host halos with virial mass 10^10.5 M_sun
< M_host < 10^15 M_sun. We predict a steep rise of roughly two dex in IHL
metallicity from the scales of small to large spiral galaxies. In terms of the
total dynamical mass M_host of the host systems under consideration, we predict
diffuse light metallicities ranging from Z_IHL < -2.5 for M_host ~ 10^11 M_sun,
to Z_IHL ~ -1.0 for M_host ~ 10^12 M_sun. In larger systems, we predict a
gradual flattening of this trend with Z_IHL ~ -0.4 for M_host ~ 10^13 M_sun,
increasing to Z_IHL ~ 0.1 for M_host ~ 10^15 M_sun. This behavior is coincident
with a narrowing of the intrahalo metallicity distribution as host mass
increases. The observable distinction in surface brightness between old,
metal-poor IHL stars and more metal-rich, dynamically-younger tidal streams is
of crucial importance when estimating the chemical abundance of an intrahalo
population with multiple origins.


title:
Latest inflation model constraints from cosmic microwave background
  measurements

abstract:
  In this addendum to Phys.Rev. D74 (2006) 023502, we present an update of
cosmological constraints on single-field inflation in light of the Wilkinson
Microwave Ansiotropy Probe satellite mission five-year results (WMAP5). We find
that the cosmic microwave background data are quite consistent with a
Harrison-Zel'dovich primordial spectrum with no running and zero tensor
amplitude. We find that the three main conclusions of our analysis of the WMAP
three-year data (WMAP3) are consistent with the WMAP5 data: (1) the
Harrison--Zel'dovich model is within the 95% confidence level contours; (2)
there is no evidence for running of the spectral index of scalar perturbations;
(3) From the WMAP 5 data alone, potentials of the form $V \propto \phi^p$ are
consistent with the data for $p = 2$, and are ruled out for $p = 4$.
Furthermore, consistent with our WMAP3 analysis, we find no evidence for
primordial tensor perturbations, this time with a 95% confidence upper limit of
$r < 0.4$ for the WMAP5 data alone, and $r < 0.35$ for the WMAP5 data taken in
combination with the Arcminute Cosmology Bolometer Array (ACBAR).


title: Cyclotron enhancement of tunneling

abstract:
  A state of an electron in a quantum wire or a thin film becomes metastable,
when a static electric field is applied perpendicular to the wire direction or
the film surface. The state decays via tunneling through the created potential
barrier. An additionally applied magnetic field, perpendicular to the electric
field, can increase the tunneling decay rate for many orders of magnitude. This
happens, when the state in the wire or the film has a velocity perpendicular to
the magnetic field. According to the cyclotron effect, the velocity rotates
under the barrier and becomes more aligned with the direction of tunneling.
This mechanism can be called cyclotron enhancement of tunneling.


title:
Microphase separation in polyelectrolytic diblock copolymer melt : weak
  segregation limit

abstract:
  We present a generalized theory of microphase separation for charged-neutral
diblock copolymer melt. Stability limit of the disordered phase for salt-free
melt has been calculated using Random Phase Approximation (RPA) and
self-consistent field theory (SCFT). Explicit analytical free energy
expressions for different classical ordered microstructures (lamellar, cylinder
and sphere) are presented. We demonstrate that chemical mismatch required for
the onset of microphase separation ($\chi^{\star} N$) in charged-neutral
diblock melt is higher and the period of ordered microstructures is lower than
those for the corresponding neutral-neutral diblock system. Theoretical
predictions on the period of ordered structures in terms of Coulomb
electrostatic interaction strength, chain length, block length, and the
chemical mismatch between blocks are presented. SCFT has been used to go beyond
the stability limit, where electrostatic potential and charge distribution are
calculated self-consistently. Stability limits calculated using RPA are in
perfect agreement with the corresponding SCFT calculations. Limiting laws for
stability limit and the period of ordered structures are presented and
comparisons are made with an earlier theory. Also, transition boundaries
between different morphologies have been investigated.


title: Some exact solutions for the Caudrey-Dodd-Gibbon equation

abstract:
  In this paper we show some exact solutions for the Caudrey-Dodd-Gibbon
equation (CDG equation). These solutions are obtained via \circledR
\emph{Mathematica} 6.0 by the projective Riccati equation method.


title: Projective C*-Algebras and Boundary Maps

abstract:
  Both boundary maps in K-theory are expressed in terms of surjections from
projective C*-algebras to semiprojective C*-algebras.


title:
Tomonaga-Luttinger liquid in quasi-one-dimensional antiferromagnet
  BaCo2V2O8 in magnetic fields

abstract:
  Motivated by recent studies on the quasi-one-dimensional (1D) antiferromagnet
BaCo2V2O8, we investigate the Tomonaga-Luttinger-liquid properties of the 1D
S=1/2 XXZ Heisenberg-Ising model in magnetic fields. By using the Bethe ansatz
solution, thermodynamic quantities and the divergence exponent of the NMR
relaxation rate are calculated. We observe a magnetization minimum as a
function of temperature (T) close to the critical field. As the magnetic field
approaches the critical field, the minimum temperature asymptotically
approaches the universal relation in agreement with the recent results by Maeda
et al. in Phys. Rev. Lett. 99 (2007) 057205. We observe T-linear specific heat
below the temperature of the magnetization minimum. The field dependence of its
coefficient agrees with the results based on conformal field theory. The field
dependence of the divergence exponent of the NMR relaxation rate with
decreasing temperature is obtained, indicating a change in the critical
properties. The results are discussed in connection with experiments on
BaCo2V2O8.


title: FUSE Observations of the Loop I/Local Bubble Interaction Region

abstract:
  We used the FUSE (Far Ultraviolet Spectroscopic Explorer) satellite to
observe OVI emission along two sightlines towards the edge of the interaction
zone (IZ) between the Loop I superbubble and the Local Bubble. One sightline
was chosen because material in the interaction zone blocks distant X-ray
emission, and should thus do the same for non-local OVI emission. We measured
an OVI intensity of I_shadowed = 2750 +- 550 L.U. along this `Shadowed'
sightline, and I_unshadowed = 10800 +- 1200 L.U. along the other sightline.
Given these results, very little (< 800 L.U.) of the emission arises from the
near side of the interaction zone, which likely has an HI column density of
about 4e+20 cm-2 along the `Shadowed' sightline. The OVI emission arising
within Loop I (~1e+4 L.U.) is probably associated with gas of n_e ~ 0.1 cm-3
and an emitting pathlength of ~1.2 pc, suggesting it arises at interfaces
rather than from gas filling Loop I. In contrast, the CIII emission is similar
along both sightlines, indicating that much of the emission likely arises on
the near side of the interaction zone.


title:
Exploring an S-matrix for gravitational collapse II: a momentum space
  analysis

abstract:
  We complement our earlier position-space exploration of a recently proposed
S-matrix for transplanckian scattering by a momentum-space analysis. As in the
previous paper, we restrict ourselves to the case of axisymmetric collisions of
extended sources. Comparison between the two formulations allows for several
cross-checks while showing their complementary advantages. In particular, the
momentum-space formulation leads to an easier computation of the
emitted-graviton spectra and to an attempt to study the system beyond its
critical points into the presumed gravitational-collapse regime.


title: Dark Energy Detected with Supervoids and Superclusters

abstract:
  The observed apparent acceleration of the universe is usually attributed to
negative pressure from a mysterious dark energy. This acceleration causes the
gravitational potential to decay, heating or cooling photons travelling through
crests or troughs of large-scale matter density fluctuations. This phenomenon,
the late-time integrated Sachs-Wolfe (ISW) effect, has been detected, albeit at
low significance, by cross-correlating various galaxy surveys with the Cosmic
Microwave Background (CMB). Recently, the best evidence has come from the
statistical combination of results from multiple correlated galaxy data sets.
Here we show that vast structures identified in a galaxy survey project an
image onto the CMB; stacking regions aligned with superclusters produces a hot
spot, and supervoids, a cold spot. At over 4 sigma, this is the clearest
evidence of the ISW effect to date. For the first time, our findings pin the
effect to discrete structures. The ISW signal from supervoids and superclusters
can be combined with other cosmological probes to constrain dark energy and
cosmological parameters. In addition, our findings make it more plausible that
the extreme Cold Spot and other anomalies in the CMB are caused by supervoids.


title:
Measurement of Azimuthal Asymmetries in Inclusive Production of Hadron
  Pairs in e+e- Annihilation at \sqrt{s} = 10.58 GeV

abstract:
  The Collins effect connects transverse quark spin with a measurable azimuthal
asymmetry in the yield of hadronic fragments around the quark's momentum
vector. Using two different reconstruction methods we measure statistically
significant azimuthal asymmetries for charged pion pairs in e+e- annihilation
at center-of-mass energies of 10.52 GeV and 10.58 GeV, which can be attributed
to the fragmentation of primordial quarks with transverse spin components. The
measurement was performed using a dataset of 547 fb^{-1} collected by the Belle
detector at KEKB improving the statistics of the previously published results
by nearly a factor of 20.


title: Synchronization in complex networks

abstract:
  Synchronization processes in populations of locally interacting elements are
in the focus of intense research in physical, biological, chemical,
technological and social systems. The many efforts devoted to understand
synchronization phenomena in natural systems take now advantage of the recent
theory of complex networks. In this review, we report the advances in the
comprehension of synchronization phenomena when oscillating elements are
constrained to interact in a complex network topology. We also overview the new
emergent features coming out from the interplay between the structure and the
function of the underlying pattern of connections. Extensive numerical work as
well as analytical approaches to the problem are presented. Finally, we review
several applications of synchronization in complex networks to different
disciplines: biological systems and neuroscience, engineering and computer
science, and economy and social sciences.


title: Tripartite entanglement transformations and tensor rank

abstract:
  Understanding the nature of multipartite entanglement is a central mission of
quantum information theory. To this end, we investigate the question of
tripartite entanglement convertibility. We find that there exists no easy
criterion to determine whether a general tripartite transformation can be
performed with a nonzero success probability and in fact, the problem is
NP-hard. Our results are based on the connections between multipartite
entanglement and tensor rank (also called Schmidt rank), a key concept in
algebraic complexity theory. Not only does this relationship allow us to
characterize the general difficulty in determining possible entanglement
transformations, but it also enables us to observe the previously overlooked
fact that {\em the Schmidt rank is not an additive entanglement measure}. As a
result, we improve some best known transformation rates between specific
tripartite entangled states. In addition, we find obtaining the most efficient
algorithm for matrix multiplication to be precisely equivalent to determining
the optimal rate of conversion between the Greenberger-Horne-Zeilinger state
and a triangular distribution of three Einstein-Podolsky-Rosen states.


title: Adjoint functors and tree duality

abstract:
  A family T of digraphs is a complete set of obstructions for a digraph H if
for an arbitrary digraph G the existence of a homomorphism from G to H is
equivalent to the non-existence of a homomorphism from any member of T to G. A
digraph H is said to have tree duality if there exists a complete set of
obstructions T consisting of orientations of trees. We show that if H has tree
duality, then its arc graph delta H also has tree duality, and we derive a
family of tree obstructions for delta H from the obstructions for H.
  Furthermore we generalise our result to right adjoint functors on categories
of relational structures. We show that these functors always preserve tree
duality, as well as polynomial CSPs and the existence of near-unanimity
functions.


title:
Generalized BSDE With 2-Reflecting Barriers and Stochastic Quadratic
  Growth

abstract:
  We study the existence of a solution for a one-dimensional generalized
backward stochastic differential equation with two reflecting barriers (GRBSDE
for short) under assumptions on the input data which are weaker than that on
the current literature. In particular, we construct a maximal solution for such
a GRBSDE when the terminal condition \xi is only F_T-measurable and the driver
f is continuous with general growth with respect to the variable y and
stochastic quadratic growth with respect to the variable z without assuming any
P-integrability conditions. The work is suggested by the interest the results
might have in Dynkin game problem and American game option.


title:
Spin lattices with two-body Hamiltonians for which the ground state
  encodes a cluster state

abstract:
  We present a general procedure for constructing lattices of qubits with a
Hamiltonian composed of nearest-neighbour two-body interactions such that the
ground state encodes a cluster state. We give specific details for lattices in
one-, two-, and three-dimensions, investigating both periodic and fixed
boundary conditions, as well as present a proof for the applicability of this
procedure to any graph. We determine the energy gap of these systems, which is
shown to be independent of the size of the lattice but dependent on the type of
lattice (in particular, the coordination number), and investigate the scaling
of this gap in terms of the coupling constants of the Hamiltonian. We provide a
comparative analysis of the different lattice types with respect to their
usefulness for measurement-based quantum computation.


title: Embeddings of Lie algebras, contractions and the state labelling problem

abstract:
  Many relevant applications of group theoretical methods to physical problems
are related, in some manner, to classification schemes by means of symmetry
groups. In these schemes, irreducible representations of a Lie group have to be
decomposed according to some subgroup, thus providing a labeling of states in
terms of the subgroup. This is the typical situation in nuclear physics, where
Hamiltonians are described as functions of the Casimir operators of the groups
involved in some reduction chain. This further gives an effective method to
deduce the corresponding energy formulae. It is not however infrequent that the
embedding of a Lie group as subgroup of a larger symmetry group is not
canonical, hence leading to different branching rules of representations and to
an insufficient number of labeling operators.
  The objective of this work is to review the actual developments of the
contraction method, including also reduction chains with respect to abelian
(Cartan) subalgebras. The decomposition of the invariants of the coadjoint
representation provide natural classes of labeling operators for the
corresponding embeddings, which are of interest for various specific problems
ranging from nuclear physics to the group theoretical foundations of the
periodic table of chemical elements.


title: Casimir operators induced by Maurer-Cartan equations

abstract:
  It is shown that for inhomogeneous Lie algebras
$\frak{g}=\frak{s}\overrightarrow{\oplus}_{\Lambda}(\dim \Lambda)L_{1}$
satisfying the condition $\mathcal{N}(\frak{g})=1$, the only Casimir operator
can be explicitly constructed from the Maurer-Cartan equations by means of
wedge products. It is shown that this constraint imposes sharp bounds for the
dimension of the representation $R$. The procedure is generalized to compute
also the rational invariant of some Lie algebras.


title:
Electromagnetic properties and electronic structure of iron-based
  layered superconductor LaOFeP

abstract:
  Structural, electronic, and magnetic properties of undoped and aliovalent-ion
(Ca, F)-doped LaOFeP, which undergo superconducting transitions at transition
temperatures (Tc) 4-7 K [Kamihara et al, J. Am. Chem. Soc. 128, 10012, (2006)],
were investigated. Tc of the samples varied from 2.4 to 5.5 K in the undoped
samples, and was increased up to ~7 K by Ca- and F-doping. The Tc increases are
correlated with a decrease in the lattice volume. LaOFeP exhibits paramagnetism
in the normal conducting state. Photoemission spectroscopy combined with
first-principle band calculations clarified that Fe 3d (dz2 + (dxz, dyz))
orbitals hybridized with P 3p to form a Fermi surface. The band calculations
also suggest that the 3d electron of the Fe in LaOFeP is basically in the
low-spin configuration, and that the spin moment of LaOFeP is almost quenched,
leading to the paramagnetism of the itinerant electrons.


title:
Semi-discrete solitons in arrayed waveguide structures with Kerr
  nonlinearity

abstract:
  We construct families of optical semi-discrete composite solitons (SDCSs),
with one or two independent propagation constants, supported by a planar slab
waveguide, XPM-coupled to a periodic array of stripes. Both structures feature
the cubic nonlinearity and support intrinsic modes with mutually orthogonal
polarizations. We report three species of SDCSs, odd, even, and twisted ones,
the first type being stable. Transverse motion of phase-tilted solitons, with
potential applications to beam steering, is considered too.


title: Critical surfaces for general bond percolation problems

abstract:
  We present a general method for predicting bond percolation thresholds and
critical surfaces for a broad class of two-dimensional periodic lattices,
reproducing many known exact results and providing excellent approximations for
several unsolved lattices. For the checkerboard and inhomogeneous bow-tie
lattices, the method yields predictions that agree with numerical measurements
to more than six figures, and are possibly exact.


title: The Ginibre ensemble of real random matrices and its scaling limits

abstract:
  We give a closed form for the correlation functions of ensembles of a class
of asymmetric real matrices in terms of the Pfaffian of an antisymmetric matrix
formed from a $2 \times 2$ matrix kernel associated to the ensemble. We apply
this result to the real Ginibre ensemble and compute the bulk and edge scaling
limits of its correlation functions as the size of the matrices becomes large.


title: The Second Galex Ultraviolet Variability (GUVV-2) Catalog

abstract:
  We present the second Galaxy Evolution Explorer (GALEX) Ultraviolet
Variability (GUVV-2) Catalog that contains information on 410 newly discovered
time-variable sources gained through simultaneous near (NUV 1750-2750A) and far
(FUV 1350-1750A) ultraviolet photometric observations. Source variability was
determined by comparing the NUV and/or FUV fluxes derived from orbital
exposures recorded during a series of multiple observational visits to 169
GALEX fields on the sky. These sources, which were contained within a sky-area
of 161 square deg, varied on average by amplitudes of NUV = 0.6 mag and FUV =
0.9 mag during these observations. Of the 114 variable sources in the catalog
with previously known identifications, 67 can be categorized as being active
galaxies (QSO's, Seyfert 1 or BL Lac objects). The next largest groups of UV
variables are RR Lyrae stars, X-ray sources and novae.
  By using a combination of UV and visible color-color plots we have been able
to tentatively identify 36 possible RR Lyrae and/or Delta Scuti type stars, as
well as 35 probable AGN's, many of which may be previously unidentified QSO's
or blazars. Finally, we show data for 3 particular variable objects: the
contact binary system of SDSS J141818.97+525006.7, the eclipsing dwarf nova
system of IY UMa and the highly variable unidentified source SDSS
J104325.06+563258.1.


title:
Large Phase of B_s-\bar B_s Mixing in Supersymmetric Grand Unified
  Theories

abstract:
  We consider the possibility of a large phase of B_s-\bar B_s mixing in
supersymmetric SU(5) and SO(10) models. We find that in the SU(5) model, the
magnitude of this phase is correlated with the branching ratio of \tau ->
\mu\gamma and the phase can be within 2\sigma of the recent UTfit analysis. In
the case of SO(10) models, this correlation can be relaxed and a large phase
can be obtained. In this scenario, a non-zero value of CP asymmetry for B ->
X_s\gamma will be predicted. We predict the sparticle mass ranges for the LHC
for these models once the UTfit result is accommodated and discuss the dark
matter and the anomalous magnetic moment constraints on this analysis.


title: Resolving The ISM Surrounding GRBs with Afterglow Spectroscopy

abstract:
  We review current research related to spectroscopy of gamma-ray burst (GRB)
afterglows with particular emphasis on the interstellar medium (ISM) of the
galaxies hosting these high redshift events. These studies reveal the physical
conditions of star-forming galaxies and yield clues to the nature of the GRB
progenitor. We offer a pedagogical review of the experimental design and review
current results. The majority of sightlines are characterized by large HI
column densities, negligible molecular fraction, the ubiquitous detection of UV
pumped fine-structure transitions, and metallicities ranging from 1/100 to
nearly solar abundance.


title:
Motion of quantum particle in dilute Bose-Einstein condensate at zero
  temperature

abstract:
  The motion of single quantum particle through Bose-Einstein condensate (BEC)
is considered within perturbation theory with respect to the particle-BEC
interaction. The Hamiltonian of BEC is diagonalized by means of Bogoliubov's
method. The process of dissipation due to the creation of excitation in BEC is
analyzed and the dissipation rate is calculated in the lowest order of
perturbation theory. The Landau's criterion for energy dissipation in BEC is
then recovered. The energy spectrum of the impurity particle due to the
interaction with BEC and its effective mass are evaluated.


title: W-Extended Logarithmic Minimal Models

abstract:
  We consider the continuum scaling limit of the infinite series of Yang-Baxter
integrable logarithmic minimal models LM(p,p') as `rational' logarithmic
conformal field theories with extended W symmetry. The representation content
is found to consist of 6pp'-2p-2p' W-indecomposable representations of which
2p+2p'-2 are of rank 1, 4pp'-2p-2p' are of rank 2, while the remaining
2(p-1)(p'-1) are of rank 3. We identify these representations with suitable
limits of Yang-Baxter integrable boundary conditions on the lattice. The
W-indecomposable rank-1 representations are all W-irreducible while we present
a conjecture for the embedding patterns of the W-indecomposable rank-2 and -3
representations. The associated W-extended characters are all given explicitly
and decompose as finite non-negative sums of W-irreducible characters. The
latter correspond to W-irreducible subfactors and we find that there are
2pp'+(p-1)(p'-1)/2 of them. We present fermionic character expressions for some
of the rank-2 and all of the rank-3 W-indecomposable representations. To
distinguish between inequivalent W-indecomposable representations of identical
characters, we introduce `refined' characters carrying information also about
the Jordan-cell content of a representation. Using a lattice implementation of
fusion on a strip, we study the fusion rules for the W-indecomposable
representations and find that they generate a closed fusion algebra, albeit one
without identity for p>1. We present the complete set of fusion rules and
interpret the closure of this fusion algebra as confirmation of the proposed
extended symmetry. Finally, 2pp' of the W-indecomposable representations are in
fact W-projective representations and they generate a closed fusion subalgebra.


title:
Buckling and competition of energy and entropy lead conformation of
  single-walled carbon nanocones

abstract:
  Using a continuum model, expressions for the elastic energy, defect energy,
structure entropy, and mixing entropy of carbon nanocones are proposed
analytically. The optimal conformation of carbon nanocones is studied by
imposing minimization of free energy and analyzing the effects that the
buckling of a nanocone's walls have during formation. The model explains the
experimentally observed preference of 19.2 degrees for the cone angle of carbon
nanocone. Furthermore, it predicts the optimal conformation of carbon nanocones
to result in a cone angle of 19.2 degrees, radius of 0.35 nm, and critical
length of 24 nm, all of which agree very well with experimental observations.


title:
Anomalous dispersion and negative group velocity in a coherence-free
  cold atomic medium

abstract:
  We have observed the propagation of an approximately 35 ns long light pulse
with a negative group velocity through a laser-cooled 85Rb atomic medium. The
anomalous dispersion results from linear atom-light interaction, and is
unrelated to long-lived ground state coherences often associated with fast
light in atomic media. The observed negative group velocity (-c/360) in the Rb
magneto-optical trap for a pulse attenuated by less than 50% is in good
agreement with the value of dispersion measured independently by an RF
heterodyne method. The spectral region of anomalous dispersion is between 15
and 40 MHz, which is an order of magnitude wider than that typically associated
with ground-state coherences.


title:
Equilibrium conformation of polymer chains with noncircular cross
  section

abstract:
  In this paper we derive the general equilibrium equations of a polymer chain
with a noncircular cross section by the variation of the free energy
functional. From the equilibrium equation of the elastic ribbon we derive
analytically the equilibrium conformations both of the helical ribbons and the
twisted ribbons. We find that the pitch angle of the helical ribbons depends on
the ratio of the torsional rigidity to the bending one. For the twisted
ribbons, the rotation rate depends on the spontaneous torsion, which is
determined by the elastic properties of the polymers. Our results for helical
and twisted ribbons strongly indicate that the formation of these structures is
determined by their elastic properties.


title: Lossless Compression with Security Constraints

abstract:
  Secure distributed data compression in the presence of an eavesdropper is
explored. Two correlated sources that need to be reliably transmitted to a
legitimate receiver are available at separate encoders. Noise-free, limited
rate links from the encoders to the legitimate receiver, one of which can also
be perfectly observed by the eavesdropper, are considered. The eavesdropper
also has its own correlated observation. Inner and outer bounds on the
achievable compression-equivocation rate region are given. Several different
scenarios involving the side information at the transmitters as well as
multiple receivers/eavesdroppers are also considered.


title: Lossy Source Transmission over the Relay Channel

abstract:
  Lossy transmission over a relay channel in which the relay has access to
correlated side information is considered. First, a joint source-channel
decode-and-forward scheme is proposed for general discrete memoryless sources
and channels. Then the Gaussian relay channel where the source and the side
information are jointly Gaussian is analyzed. For this Gaussian model, several
new source-channel cooperation schemes are introduced and analyzed in terms of
the squared-error distortion at the destination. A comparison of the proposed
upper bounds with the cut-set lower bound is given, and it is seen that joint
source-channel cooperation improves the reconstruction quality significantly.
Moreover, the performance of the joint code is close to the lower bound on
distortion for a wide range of source and channel parameters.


title: Quantum fields near phantom-energy `sudden' singularities

abstract:
  This paper is committed to calculations near a type of future singularity
driven by phantom energy. At the singularities considered, the scale factor
remains finite but its derivative diverges. The general behavior of barotropic
phantom energy producing this singularity is calculated under the assumption
that near the singularity such fluid is the dominant contributor. We use the
semiclassical formula for renormalized stress tensors of conformally invariant
fields in conformally flat spacetimes and analyze the softening/enhancing of
the singularity due to quantum vacuum contributions. This dynamical analysis is
then compared to results from thermodynamical considerations. In both cases,
the vacuum states of quantized scalar and spinor fields strengthen the
accelerating expansion near the singularity whereas the vacuum states of vector
fields weaken it.


title: Cocycle Superrigidity for Profinite Actions of Property (T) Groups

abstract:
  Consider a free ergodic measure preserving profinite action
$\Gamma\curvearrowright X$ (i.e. an inverse limit of actions
$\Gamma\curvearrowright X_n$, with $X_n$ finite) of a countable property (T)
group $\Gamma$ (more generally of a group $\Gamma$ which admits an infinite
normal subgroup $\Gamma_0$ such that the inclusion $\Gamma_0\subset\Gamma$ has
relative property (T) and $\Gamma/\Gamma_0$ is finitely generated) on a
standard probability space $X$. We prove that if $w:\Gamma\times X\to \Lambda$
is a measurable cocycle with values in a countable group $\Lambda$, then $w$ is
cohomologous to a cocycle $w'$ which factors through the map $\Gamma\times X\to
\Gamma\times X_n$, for some $n$. As a corollary, we show that any orbit
equivalence of $\Gamma\curvearrowright X$ with any free ergodic measure
preserving action $\Lambda\curvearrowright Y$ comes from a (virtual) conjugacy
of actions.


title:
High-Precision Charm-Quark Mass and QCD Coupling from Current-Current
  Correlators in Lattice and Continuum QCD

abstract:
  We use lattice QCD simulations, with MILC gluon configurations and HISQ
c-quark propagators, to make very precise determinations of moments of
charm-quark pseudoscalar, vector and axial-vector correlators. These moments
are combined with new four-loop results from continuum perturbation theory to
obtain several new determinations of the MSbar mass of the charm quark and of
the MSbar coupling. We find m_c(3GeV)=0.986(10)GeV, or, equivalently,
m_c(m_c)=1.268(9)GeV, both for n_f=4 flavors; and
alpha_msb(3GeV,n_f=4)=0.251(6), or, equivalently,
alpha_\msb(M_Z,n_f=5)=0.1174(12). The new mass agrees well with results from
continuum analyses of the vector correlator using experimental data for e+e-
annihilation (instead of using lattice QCD simulations). These lattice and
continuum results are the most accurate determinations to date of this mass.
Ours is also one of the most accurate determinations of the QCD coupling by any
method.


title:
Neutrino Masses, Leptogenesis, and Unification in the Absence of Low
  Energy Supersymmetry

abstract:
  We explore generating the dimension five operator leading to neutrino masses
by integrating out heavy SU(2)_L triplet fermions. We exhibit a model that has
a neutrino mass matrix consistent with observations. In addition, the model is
capable of producing the observed baryon asymmetry, and unification can be
achieved without dangerous proton decay. Supersymmetry can be broken at the
fundamental scale with no supersymmetric signal at low energies.


title:
Superconducting Gap and Pseudogap in Iron-Based Layered Superconductor
  La(O$_{1-x}$F$_x$)FeAs

abstract:
  We report high-resolution photoemission spectroscopy of newly-discovered
iron-based layered superconductor La(O$_{0.93}$F$_{0.07}$)FeAs (Tc = 24 K). We
found that the superconducting gap shows a marked deviation from the isotropic
s-wave symmetry. The estimated gap size at 5 K is 3.6 meV in the s- or axial
p-wave case, while it is 4.1 meV in the polar p- or d-wave case. We also found
a pseudogap of 15-20 meV above Tc, which is gradually filled-in with increasing
temperature and closes at temperature far above Tc similarly to copper-oxide
high-temperature superconductors.


title:
Response to Comments on PCA Based Hurst Exponent Estimator for fBm
  Signals Under Disturbances

abstract:
  In this response, we try to give a repair to our previous proof for PCA Based
Hurst Exponent Estimator for fBm Signals by using orthogonal projection.
Moreover, we answer the question raised recently: If a centered Gaussian
process $G_t$ admits two series expansions on different Riesz bases, we may
possibly study the asymptotic behavior of one eigenvalue sequence from the
knowledge on the asymptotic behaviors of another.


title: Geometrothermodynamics of asymptotically anti - de Sitter black holes

abstract:
  We apply the formalism of geometrothermodynamics to the case of black holes
with cosmological constant in four and higher dimensions. We use a
thermodynamic metric which is invariant with respect to Legendre
transformations and determines the geometry of the space of equilibrium states.
For all known black holes in higher dimensions, we show that the curvature
scalar of the thermodynamic metric in all the cases is proportional to the heat
capacity. As a consequence, phase transitions, which correspond to divergencies
of the heat capacity, are represented geometrically as true curvature
singularities. We interpret this as a further indication that the curvature of
the thermodynamic metric is a measure of thermodynamic interaction.


title: Inclusive Jet $A_{LL}$ Measurements at STAR

abstract:
  We report STAR's preliminary measurement of the inclusive jet longitudinal
spin asymmetry $A_{LL}$ using data from the RHIC 2006 run. The 2006 data set
was taken with 200 GeV polarized proton-proton collisions and represents 4.7
$pb^{-1}$ of data. Typical beam polarizations were $\sim 55-60%$. The data are
compared with theoretical calculations of $A_{LL}$ based on various GRSV models
of the polarized parton distribution functions in the nucleon. Previous STAR
inclusive jet $A_{LL}$ and cross section measurements are also presented, as is
a discussion of constraints these data place on the allowed theoretical models.


title:
High-dimensional subset recovery in noise: Sparsified measurements
  without loss of statistical efficiency

abstract:
  We consider the problem of estimating the support of a vector $\beta^* \in
\mathbb{R}^{p}$ based on observations contaminated by noise. A significant body
of work has studied behavior of $\ell_1$-relaxations when applied to
measurement matrices drawn from standard dense ensembles (e.g., Gaussian,
Bernoulli). In this paper, we analyze \emph{sparsified} measurement ensembles,
and consider the trade-off between measurement sparsity, as measured by the
fraction $\gamma$ of non-zero entries, and the statistical efficiency, as
measured by the minimal number of observations $n$ required for exact support
recovery with probability converging to one. Our main result is to prove that
it is possible to let $\gamma \to 0$ at some rate, yielding measurement
matrices with a vanishing fraction of non-zeros per row while retaining the
same statistical efficiency as dense ensembles. A variety of simulation results
confirm the sharpness of our theoretical predictions.


title: The Exchange Parameters in Lanthanum Manganites

abstract:
  The spin-wave spectrum in the metallic ferromagnetic lantha-num cubic
manganites was investigated. The interactions with four coordination spheres
(32 neighbors) were taken into ac-count. The Heisenberg superexchange between
all manganese ions as well as double exchange between the manganese ions with
different valence were under consideration. The obtained magnon spectrum
permits to investigate dispersion relations along an any crystallographic
directions. This possibility was used for the numerical evaluation of the
exchange parameters in the compounds La0.75Ca0.25MnO3 and La0.70Ca0.30MnO3 from
the inelastic neutron scattering data.


title: Randall-Sundrum Gravitons and Black Holes at the LHC

abstract:
  Models predicting the existence of extra spatial dimensions offer compelling
and novel solutions to outstanding problems of the Standard Model. In such
models, our universe exists on a 4 dimensional brane embedded in a larger
dimensional space time. By allowing gravity to propagate in the bulk the
gravitational coupling could be comparable with the other gauge interactions
thus removing the hierarchy problem. The phenomenology of these models could
have dramatic observable effects at the LHC includingthe production and decay
of gravitons and mini black holes. In this note we summarize feasibility
studies for the discovery of strong gravitational interactions at the LHC.


title: Multiple tests of association with biological annotation metadata

abstract:
  We propose a general and formal statistical framework for multiple tests of
association between known fixed features of a genome and unknown parameters of
the distribution of variable features of this genome in a population of
interest. The known gene-annotation profiles, corresponding to the fixed
features of the genome, may concern Gene Ontology (GO) annotation, pathway
membership, regulation by particular transcription factors, nucleotide
sequences, or protein sequences. The unknown gene-parameter profiles,
corresponding to the variable features of the genome, may be, for example,
regression coefficients relating possibly censored biological and clinical
outcomes to genome-wide transcript levels, DNA copy numbers, and other
covariates. A generic question of great interest in current genomic research
regards the detection of associations between biological annotation metadata
and genome-wide expression measures. This biological question may be translated
as the test of multiple hypotheses concerning association measures between
gene-annotation profiles and gene-parameter profiles. A general and rigorous
formulation of the statistical inference question allows us to apply the
multiple hypothesis testing methodology developed in [Multiple Testing
Procedures with Applications to Genomics (2008) Springer, New York] and related
articles, to control a broad class of Type I error rates, defined as
generalized tail probabilities and expected values for arbitrary functions of
the numbers of Type I errors and rejected hypotheses. The resampling-based
single-step and stepwise multiple testing procedures of [Multiple Testing
Procedures with Applications to Genomics (2008) Springer, New York] take into
account the joint distribution of the test statistics and provide Type I error
control in testing problems involving general data generating distributions
(with arbitrary dependence structures among variables), null hypotheses, and
test statistics.


title:
Baroclinic Generation of Potential Vorticity in an Embedded Planet-Disk
  System

abstract:
  We use a multi-dimensional hydrodynamics code to study the gravitational
interaction between an embedded planet and a protoplanetary disk with emphasis
on the generation of vortensity (Potential Vorticity or PV) through a
Baroclinic Instability. We show that the generation of PV is very common and
effective in non-barotropic disks through the Baroclinic Instability,
especially within the coorbital region. Our results also complement previous
work that non-axisymmetric Rossby-Wave Instabilities (RWIs, Lovelace et al.
1999) are likely to develop at local minima of PV distribution that are
generated by the interaction between a planet and an inviscid barotropic disk.
The development of RWIs results in non-axisymmetric density blobs, which exert
stronger torques onto the planet when they move to the vicinity of the planet.
Hence, large amplitude oscillations are introduced to the time behavior of the
total torque acted on the planet by the disk. In current simulations, RWIs do
not change the overall picture of inward orbital migration but cause a
non-monotonic behavior to the migration speed. As a side effect, RWIs also
introduce interesting structures into the disk. These structures may help the
formation of Earth-like planets in the Habitable Zone or Hot Earths interior to
a close-in giant planet.


title: Hot Jupiters and stellar magnetic activity

abstract:
  Recent observations suggest that stellar magnetic activity may be influenced
by the presence of a close-by giant planet. Specifically, chromospheric hot
spots rotating in phase with the planet orbital motion have been observed
during some seasons in a few stars harbouring hot Jupiters. The spot leads the
subplanetary point by a typical amount of about 60-70 degrees, with the extreme
case of upsilon And where the angle is about 170 degrees. The interaction
between the star and the planet is described considering the reconnection
between the stellar coronal field and the magnetic field of the planet.
Reconnection events produce energetic particles that moving along magnetic
field lines impact onto the stellar chromosphere giving rise to a localized hot
spot. A simple magnetohydrostatic model is introduced to describe the coronal
magnetic field of the star connecting its surface to the orbiting planet. The
field is assumed to be axisymmetric around the rotation axis of the star and
its configuration is more general than a linear force-free field. With a
suitable choice of the free parameters, the model can explain the phase
differences between the hot spots and the planets observed in HD 179949,
upsilon And, HD 189733, and tau Bootis, as well as their visibility modulation
on the orbital period and seasonal time scales. The possible presence of cool
spots associated with the planets in tau Boo and HD 192263 cannot be explained
by the present model. However, we speculate about the possibility that
reconnection events in the corona may influence subphotospheric dynamo action
in those stars producing localized photospheric (and chromospheric) activity
migrating in phase with their planets.


title:
A collocated finite volume scheme to solve free convection for general
  non-conforming grids

abstract:
  We present a new collocated numerical scheme for the approximation of the
Navier-Stokes and energy equations under the Boussinesq assumption for general
grids, using the velocity-pressure unknowns. This scheme is based on a recent
scheme for the diffusion terms. Stability properties are drawn from particular
choices for the pressure gradient and the non-linear terms. Numerical results
show the accuracy of the scheme on irregular grids.


title: Energy transport in stochastically perturbed lattice dynamics

abstract:
  We consider lattice dynamics with a small stochastic perturbation of order
ε and prove that for a space-time scale of order \varepsilon\^-1 the local
spectral density (Wigner function) evolves according to a linear transport
equation describing inelastic collisions. For an energy and momentum conserving
chain the transport equation predicts a slow decay, as 1/\sqrt{t}, for the
energy current correlation in equilibrium. This is in agreement with previous
studies using a different method.

categories: math.PR cond-mat.stat-mech math-ph math.MP


title: Geometry and Dynamics for Hierarchical Regular Networks

abstract:
  The recently introduced hierarchical regular networks HN3 and HN4 are
analyzed in detail. We use renormalization group arguments to show that HN3, a
3-regular planar graph, has a diameter growing as \sqrt{N} with the system
size, and random walks on HN3 exhibit super-diffusion with an anomalous
exponent d_w = 2 - \log_2\phi = 1.306..., where \phi = (\sqrt{5} + 1)/2 =
1.618... is the "golden ratio." In contrast, HN4, a non-planar 4-regular graph,
has a diameter that grows slower than any power of N, yet, fast than any power
of \ln N . In an annealed approximation we can show that diffusive transport on
HN4 occurs ballistically (d_w = 1). Walkers on both graphs possess a first-
return probability with a power law tail characterized by an exponent \mu = 2
-1/d_w . It is shown explicitly that recurrence properties on HN3 depend on the
starting site.


title:
Diffusion conductivity and weak localization in two-dimensional
  structures with electrostatically induced random antidots array

abstract:
  Results of experimental study of the weak localization phenomenon in 2D
system with artificial inhomogeneity of potential relief are presented. It is
shown that the shape of the magnetoconductivity curve is determined by the
statistics of closed paths. The area distribution function of closed paths has
been obtained using the Fourier transformation of the magnetoconductivity
curves taken at different temperatures. The experimental results are found in a
qualitative agreement with the results of computer simulation.


title: Probing Quantum Nonlinearities through Neutrino Oscillations

abstract:
  We investigate potential quantum nonlinear corrections to Dirac's equation
through its sub-leading effect on neutrino oscillation probabilities. Working
in the plane-wave approximation and in the $\mu-\tau$ sector, we explore
various classes of nonlinearities, with or without an accompanying Lorentz
violation. The parameters in our models are first delimited by current
experimental data before they are used to estimate corrections to oscillation
probabilities. We find that only a small subset of the considered
nonlinearities have the potential to be relevant at higher energies and thus
possibly detectable in future experiments. A falsifiable prediction of our
models is an energy dependent effective mass-squared, generically involving
fractional powers of the energy.


title:
Probability of metastable configurations in spherical three-dimensional
  Yukawa crystals

abstract:
  Recently the occurrence probabilities of ground- and metastable states of
three-dimensional Yukawa clusters with 27 and 31 particles have been analyzed
in dusty plasma experiments [Block et al., Physics of Plasmas 15, 040701
(2008)]. There it was found that, in many cases, the ground state appeared
substantially less frequently than excited states. Here we analyze this
question theoretically by means of molecular dynamics (MD) and Monte Carlo
simulations and an analytical method based on the canonical partition function.
We confirm that metastable states can occur with a significantly higher
probability than the ground state. The results strongly depend on the screening
parameter of the Yukawa interaction and the damping coefficient used in the MD
simulations. The analytical method allows one to gain insight into the
mechanisms being responsible for the occurrence probabilities of metastable
states in strongly correlated finite systems.


title:
Variation of mass in primordial nucleosynthesis as a test of Induced
  Matter Brane Gravity

abstract:
  The variation of mass in induced matter theory using Ceroch-Stewart-Walter
perturbations of submanifolds [1] is redefined. It is shown that the deviation
of primordial Helium production due to a variation on the difference between
the rest mass of the nucleus is in agrement with induced matter brane gravity.


title: Hyperbolic Weyl groups and the four normed division algebras

abstract:
  We study the Weyl groups of hyperbolic Kac-Moody algebras of `over-extended'
type and ranks 3, 4, 6 and 10, which are intimately linked with the four normed
division algebras K=R,C,H,O, respectively. A crucial role is played by integral
lattices of the division algebras and associated discrete matrix groups. Our
findings can be summarized by saying that the even subgroups, W^+, of the
Kac-Moody Weyl groups, W, are isomorphic to generalized modular groups over K
for the simply laced algebras, and to certain finite extensions thereof for the
non-simply laced algebras. This hints at an extended theory of modular forms
and functions.


title: Three months journeying of a Hawaiian monk seal

abstract:
  Hawaiian monk seals (Monachus schauinslandi) are endemic to the Hawaiian
Islands and are the most endangered species of marine mammal that lives
entirely within the jurisdiction of the United States. The species numbers
around 1300 and has been declining owing, among other things, to poor juvenile
survival which is evidently related to poor foraging success. Consequently,
data have been collected recently on the foraging habitats, movements, and
behaviors of monk seals throughout the Northwestern and main Hawaiian Islands.
Our work here is directed to exploring a data set located in a relatively
shallow offshore submerged bank (Penguin Bank) in our search of a model for a
seal's journey. The work ends by fitting a stochastic differential equation
(SDE) that mimics some aspects of the behavior of seals by working with
location data collected for one seal. The SDE is found by developing a time
varying potential function with two points of attraction. The times of location
are irregularly spaced and not close together geographically, leading to some
difficulties of interpretation. Synthetic plots generated using the model are
employed to assess its reasonableness spatially and temporally. One aspect is
that the animal stays mainly southwest of Molokai. The work led to the
estimation of the lengths and locations of the seal's foraging trips.


title: Constraints on Unparticle Interaction from $b\to s \gamma$

abstract:
  We study unparticle effects on $b\to s \gamma$. The unparticle contributions
can contribute significantly to both left- and right-handed chirality
amplitudes. Using available experimental data and SM calculation for $B\to X_s
\gamma$, we obtain constraints on various vector and scalar unparticle
couplings. We find that the constraints sensitively depend on the unparticle
dimension $d_\U$. For $d_\U$ close to one, the constraints can be very
stringent. The constraints become weak when $d_\U$ is increased. In general the
constraints on scalar unparticle couplings are weaker than those for vector
unparticle couplings. Sizeable coupling strength for unparticles with quarks is
still allowed. We also show that polarization measurement in $\Lambda_b \to
\Lambda \gamma$ can further constrain the couplings.


title:
New parameterization of effective nucleon-nucleon $t$-matrix interaction
  for scattering at intermediate energies

abstract:
  The model suggested by Love and Franey for description of the nucleon-nucleon
interaction was used as the base. The new fitting of the model parameters was
done in the energy range from 100 MeV up to 1100 MeV. It is based on the modern
partial-wave-analysis solution for NN-amplitudes. The three observables:
differential cross section, vector analyzing power, and spin correlation
coefficient -- were obtained at every energy. The results are compared with
existing the experimental data.


title:
Spontaneous Symmetry Breaking of Lorentz and (Galilei) Boosts in
  (Relativistic) Many-Body Systems

abstract:
  We extend a result by Ojima on spontaneous symmetry breaking of Lorentz
boosts in thermal (KMS) states and show that it is in fact a special case in a
more general class of examples of spontaneous symmetry breaking of Lorentz
symmetry in relativistic many-body systems. Furthermore we analyse the nature
of the corresponding Goldstone phenomenon and the type of Goldstone excitations
(provided they have particle character).


title:
Representation of nonequilibrium steady states in large mechanical
  systems

abstract:
  Recently a novel concise representation of the probability distribution of
heat conducting nonequilibrium steady states was derived. The representation is
valid to the second order in the ``degree of nonequilibrium'', and has a very
suggestive form where the effective Hamiltonian is determined by the excess
entropy production. Here we extend the representation to a wide class of
nonequilibrium steady states realized in classical mechanical systems where
baths (reservoirs) are also defined in terms of deterministic mechanics. The
present extension covers such nonequilibrium steady states with a heat
conduction, with particle flow (maintained either by external field or by
particle reservoirs), and under an oscillating external field. We also simplify
the derivation and discuss the corresponding representation to the full order.


title:
Coherent forward stimulated Brillouin scattering of a spatially
  incoherent laser beam in a plasma and its effect on beam spray

abstract:
  A statistical model for forward stimulated Brillouin scattering (FSBS) is
developed for a spatially incoherent, monochromatic, laser beam propagating in
a plasma. A threshold for the average power in a speckle is found, well below
the self-focusing one, above which the laser beam spatial incoherence can not
prevent the coherent growth of FSBS. Three-dimensional simulations confirm its
existence and reveal the onset of beam spray above it. From these results, we
propose a new figure of merit for the control of the propagation through a
plasma of a spatially incoherent laser beam.


title: Exact Multi-Restricted Schur Polynomial Correlators

abstract:
  We derive a product rule satisfied by restricted Schur polynomials. We focus
mostly on the case that the restricted Schur polynomial is built using two
matrices, although our analysis easily extends to more than two matrices. This
product rule allows us to compute exact multi-point correlation functions of
restricted Schur polynomials, in the free field theory limit. As an example of
the use of our formulas, we compute two point functions of certain single trace
operators built using two matrices and three point functions of certain
restricted Schur polynomials, exactly, in the free field theory limit. Our
results suggest that gravitons become strongly coupled at sufficiently high
energy, while the restricted Schur polynomials for totally antisymmetric
representations remain weakly interacting at these energies. This is in perfect
accord with the half-BPS (single matrix) results of hep-th/0512312. Finally, by
studying the interaction of two restricted Schur polynomials we suggest a
physical interpretation for the labels of the restricted Schur polynomial: the
composite operator $\chi_{R,(r_n,r_m)}(Z,X)$ is constructed from the half BPS
``partons'' $\chi_{r_n}(Z)$ and $\chi_{r_m}(X)$.


title: Ces\`aro means of Jacobi expansions on the parabolic biangle

abstract:
  We study Ces\`aro $(C,\delta)$ means for two-variable Jacobi polynomials on
the parabolic biangle $B=\{(x_1,x_2)\in{\mathbb R}^2:0\leq x_1^2\leq x_2\leq
1\}$. Using the product formula derived by Koornwinder & Schwartz for this
polynomial system, the Ces\`aro operator can be interpreted as a convolution
operator. We then show that the Ces\`aro $(C,\delta)$ means of the orthogonal
expansion on the biangle are uniformly bounded if $\delta>\alpha+\beta+1$,
$\alpha-\frac 12\geq\beta\geq 0$. Furthermore, for
$\delta\geq\alpha+2\beta+\frac 32$ the means define positive linear operators.


title:
DNA Probabilities in People v. Prince: When are racial and ethnic
  statistics relevant?

abstract:
  When a defendant's DNA matches a sample found at a crime scene, how
compelling is the match? To answer this question, DNA analysts typically use
relative frequencies, random-match probabilities or likelihood ratios. They
compute these quantities for the major racial or ethnic groups in the United
States, supplying prosecutors with such mind-boggling figures as ``one in nine
hundred and fifty sextillion African Americans, one in one hundred and thirty
septillion Caucasians, and one in nine hundred and thirty sextillion
Hispanics." In People v. Prince, a California Court of Appeals rejected this
practice on the theory that only the perpetrator's race is relevant to the
crime; hence, it is impermissible to introduce statistics about other races.
This paper critiques this reasoning. Relying on the concept of likelihood, it
presents a logical justification for referring to a range of races and
identifies some problems with the one-race-only rule. The paper also notes some
ways to express the probative value of a DNA match quantitatively without
referring to variations in DNA profile frequencies among races or ethnic
groups.


title: Interstellar atoms, molecules and diffuse bands toward SN2006X in M100

abstract:
  Aims. Supernovae offer the unique possibility to probe diffuse extra-galactic
sightlines via observation of the optical transitions of atoms, molecules and
the diffuse interstellar bands (DIBs). Through optical spectroscopy the
presence of (complex) molecules in distant galaxies can be established.
  Methods. High resolution optical (3300 -- 6800 Angstrom) spectra of SN2006X
at different phase obtained with UVES on the VLT were reduced and analysed.
  Results. In addition to previously detected atomic (NaI and CaII) and
molecular (CN) transitions we present detections of DIBs (6196, 6283 Angstrom),
diatomic molecules (CH, CH+) and neutral atoms (CaI) in the spectra of SN2006X
taken at different phases (at 2 days before and 14 and 61 days after the
brightness maximum). An analysis of the absorption profiles shows no variation
between phases in the abundance, nor the central velocities (within 3-sigma
error bars) of the (dense) gas tracers (CH, CH+ and CaI) and the DIBs. This is
consistent with the conclusion in the literature that SN2006X exploded behind a
dense interstellar cloud (inferred from strong atomic sodium and calcium lines
and CN transitions) which caused strong photometric reddening but whose
material was not directly affected by the supernova explosion. The CH and CN
column densities correspond to a reddening of one magnitude following the
Galactic correlation derived previously. The 6196 and 6283 lines detected in
the M100 ISM are under-abundant by factor of 2.5 to 3.5 (assuming a visual
extinction of ~2 mag) compared to the average Galactic ISM relationship. Upper
limits for 6379 and 6613 DIBs show that these are at least a factor of seven
weaker. Therefore, the Galactic DIB-reddening relation does not seem to hold in
M100, although the lower gas-to-dust ratio may further reduce this discrepancy.


title:
Homogeneous nucleation under shear in a two-dimensional Ising model:
  cluster growth, coalescence and breakup

abstract:
  We compute rates and pathways for nucleation in a sheared two dimensional
Ising model with Metropolis spin flip dynamics, using Forward Flux Sampling
(FFS). We find a peak in the nucleation rate at intermediate shear rate. We
analyse the origin of this peak using modified shear algorithms and committor
analysis. We find that the peak arises from an interplay between three
shear-mediated effects: shear-enhanced cluster growth, cluster coalescence and
cluster breakup. Our results show that complex nucleation behaviour can be
found even in a simple driven model system. This work also demonstrates the use
of FFS for simulating rare events, including nucleation, in nonequilibrium
systems.


title: A-infinity monads and completion

abstract:
  Given an operad A of topological spaces, we consider A-monads in a
topological category C . When A is an A-infinity-operad, any A-monad K : C -> C
can be thought of as a monad up to coherent homotopies. We define the
completion functor with respect to an A-infinity-monad and prove that it is an
A-infinity-monad itself.


title: Proposed realization of itinerant ferromagnetism in optical lattices

abstract:
  We propose to realize the itinerant ferromagnetism of two-component cold
fermionic atoms in the $p$-orbital bands in optical lattices. The band flatness
in the two-dimensional honeycomb lattice dramatically amplifies the interaction
effect driving the ferromagnetic transition even with a relatively weak
repulsive interaction. This scheme has the advantage that the stability of the
system can be maintained without suffering decaying to the molecular state as
one approaches the Feshbach resonance from the side with positive scattering
length. Experimental signatures and detections are also discussed.


title: Testing earthquake predictions

abstract:
  Statistical tests of earthquake predictions require a null hypothesis to
model occasional chance successes. To define and quantify `chance success' is
knotty. Some null hypotheses ascribe chance to the Earth: Seismicity is modeled
as random. The null distribution of the number of successful predictions -- or
any other test statistic -- is taken to be its distribution when the fixed set
of predictions is applied to random seismicity. Such tests tacitly assume that
the predictions do not depend on the observed seismicity. Conditioning on the
predictions in this way sets a low hurdle for statistical significance.
Consider this scheme: When an earthquake of magnitude 5.5 or greater occurs
anywhere in the world, predict that an earthquake at least as large will occur
within 21 days and within an epicentral distance of 50 km. We apply this rule
to the Harvard centroid-moment-tensor (CMT) catalog for 2000--2004 to generate
a set of predictions. The null hypothesis is that earthquake times are
exchangeable conditional on their magnitudes and locations and on the
predictions--a common ``nonparametric'' assumption in the literature. We
generate random seismicity by permuting the times of events in the CMT catalog.
We consider an event successfully predicted only if (i) it is predicted and
(ii) there is no larger event within 50 km in the previous 21 days. The
$P$-value for the observed success rate is $<0.001$: The method successfully
predicts about 5% of earthquakes, far better than `chance,' because the
predictor exploits the clustering of earthquakes -- occasional foreshocks --
which the null hypothesis lacks. Rather than condition on the predictions and
use a stochastic model for seismicity, it is preferable to treat the observed
seismicity as fixed, and to compare the success rate of the predictions to the
success rate of simple-minded predictions like those just described. If the
proffered predictions do no better than a simple scheme, they have little
value.


title:
Nonperturbative effects and nonperturbative definitions in matrix models
  and topological strings

abstract:
  We develop techniques to compute multi-instanton corrections to the 1/N
expansion in matrix models described by orthogonal polynomials. These
techniques are based on finding trans-series solutions, i.e. formal solutions
with exponentially small corrections, to the recursion relations characterizing
the free energy. We illustrate this method in the Hermitian, quartic matrix
model, and we provide a detailed description of the instanton corrections in
the Gross-Witten-Wadia (GWW) unitary matrix model. Moreover, we use Borel
resummation techniques and results from the theory of resurgent functions to
relate the formal multi-instanton series to the nonperturbative definition of
the matrix model. We study this relation in the case of the GWW model and its
double-scaling limit, providing in this way a nice illustration of various
mechanisms connecting the resummation of perturbative series to nonperturbative
results, like the cancellation of nonperturbative ambiguities. Finally, we
argue that trans-series solutions are also relevant in the context of
topological string theory. In particular, we point out that in topological
string models with both a matrix model and a large N gauge theory description,
the nonperturbative, holographic definition involves a sum over the
multi-instanton sectors of the matrix model


title:
Curse-of-dimensionality revisited: Collapse of the particle filter in
  very large scale systems

abstract:
  It has been widely realized that Monte Carlo methods (approximation via a
sample ensemble) may fail in large scale systems. This work offers some
theoretical insight into this phenomenon in the context of the particle filter.
We demonstrate that the maximum of the weights associated with the sample
ensemble converges to one as both the sample size and the system dimension
tends to infinity. Specifically, under fairly weak assumptions, if the ensemble
size grows sub-exponentially in the cube root of the system dimension, the
convergence holds for a single update step in state-space models with
independent and identically distributed kernels. Further, in an important
special case, more refined arguments show (and our simulations suggest) that
the convergence to unity occurs unless the ensemble grows super-exponentially
in the system dimension. The weight singularity is also established in models
with more general multivariate likelihoods, e.g. Gaussian and Cauchy. Although
presented in the context of atmospheric data assimilation for numerical weather
prediction, our results are generally valid for high-dimensional particle
filters.


title:
STM Simulation of Molecules on Ultrathin Insulating Overlayers Using
  Tight-Binding: Au-Pentacene on NaCl bilayer on Cu

abstract:
  We present a fast and efficient tight-binding (TB) method for simulating
scanning tunneling microscopy (STM) imaging of adsorbate molecules on ultrathin
insulating films. Due to the electronic decoupling of the molecule from the
metal surface caused by the presence of the insulating overlayer, the STM
images of the frontier molecular orbitals can be simulated using a very
efficient scheme, which also enables the analysis of phase shifts in the STM
current. Au-pentacene complex adsorbed on a NaCl bilayer on Cu substrate
provides an intricate model system, which has been previously studied both
experimentally and theoretically. Our calculations indicate that the
complicated shape of the molecular orbitals may cause multivalued constant
current surfaces -- leading to ambiguity of the STM image. The results obtained
using the TB method are found to be consistent with both DFT calculations and
experimental data.


title:
Limits on Low Energy Photon-Photon Scattering from an Experiment on
  Magnetic Vacuum Birefringence

abstract:
  Experimental bounds on induced vacuum magnetic birefringence can be used to
improve present photon-photon scattering limits in the electronvolt energy
range. Measurements with the PVLAS apparatus (E. Zavattini {\it et al.}, Phys.
Rev. D {\bf77} (2008) 032006) at both $\lambda = 1064$ nm and 532 nm lead to
bounds on the parameter {\it A$_{e}$}, describing non linear effects in QED, of
$A_{e}^{(1064)} < 6.6\cdot10^{-21}$ T$^{-2}$ @ 1064 nm and $A_{e}^{(532)} <
6.3\cdot10^{-21}$ T$^{-2}$ @ 532 nm, respectively, at 95% confidence level,
compared to the predicted value of $A_{e}=1.32\cdot10^{-24}$ T$^{-2}$. The
total photon-photon scattering cross section may also be expressed in terms of
$A_e$, setting bounds for unpolarized light of $\sigma_{\gamma\gamma}^{(1064)}
< 4.6\cdot10^{-62}$ m$^{2}$ and $\sigma_{\gamma\gamma}^{(532)} <
2.7\cdot10^{-60}$ m$^{2}$. Compared to the expected QED scattering cross
section these results are a factor of $\simeq2\cdot10^{7}$ higher and represent
an improvement of a factor about 500 on previous bounds based on ellipticity
measurements and of a factor of about $10^{10}$ on bounds based on direct
stimulated scattering measurements.


title: Simulation of Finite Width Effects in Physics Beyond the Standard Model

abstract:
  We present a method for the inclusion of finite width effects in the
simulation of Beyond Standard Model (BSM) physics. In order to test the
validity of the method we compare our results with matrix elements for a range
of production and decay processes in the Standard Model, Minimal Supersymmetric
Standard Model (MSSM) and Minimal Universal Extra Dimensions model (MUED). This
procedure has been implemented in the Herwig++ event generator and will be
available in a forthcoming release.


title: Semi-continuit\'e des cellules de Kazhdan-Lusztig

abstract:
  Computations in small Coxeter groups and infinite dihedral groups suggest
that Kazhdan-Lusztig cells for unequal parameters obey to some "semicontinuity"
phenomenon (as the parameter vary). The aim of this paper is to provide a
rigorous theoretical background that allows to state some precise conjectures.


title: Transformation media that turn a narrow slit into a large window

abstract:
  Based on the transformation media theory, the authors propose a way to
replace a wide window with a narrow slit filled with designed metamaterial to
achieve the same transmittance as the one of the window. Numerical simulations
for a two dimensional case are given to illustrate the ideas and the
performance of the design.


title:
Higher order influence functions and minimax estimation of nonlinear
  functionals

abstract:
  We present a theory of point and interval estimation for nonlinear
functionals in parametric, semi-, and non-parametric models based on higher
order influence functions (Robins (2004), Section 9; Li et al. (2004), Tchetgen
et al. (2006), Robins et al. (2007)). Higher order influence functions are
higher order U-statistics. Our theory extends the first order semiparametric
theory of Bickel et al. (1993) and van der Vaart (1991) by incorporating the
theory of higher order scores considered by Pfanzagl (1990), Small and McLeish
(1994) and Lindsay and Waterman (1996). The theory reproduces many previous
results, produces new non-$\sqrt{n}$ results, and opens up the ability to
perform optimal non-$\sqrt{n}$ inference in complex high dimensional models. We
present novel rate-optimal point and interval estimators for various
functionals of central importance to biostatistics in settings in which
estimation at the expected $\sqrt{n}$ rate is not possible, owing to the curse
of dimensionality. We also show that our higher order influence functions have
a multi-robustness property that extends the double robustness property of
first order influence functions described by Robins and Rotnitzky (2001) and
van der Laan and Robins (2003).


title: Methods toward better Multigrid Solver Convergence

abstract:
  I present a motivation of several areas where the Multigrid techniques can be
employed. I present typical areas where the multigrid solver might be employed.
I give an introduction to smoothers and how one might choose a preconditionor
as well as an introduction of the Multigrid technique used. Then I do a study
of the Multigrid technique while adjusting the environment conditions of the
solver and the problem such as anisotropies, the grid-levels used, the
preconditionor smoothing steps, the coordinate system and the start vector. The
problem solved here was a simple Poisson problem. The Multigrid program used an
F-cycle in this paper. I include performance study sections displaying results
of the solver behavior under the different conditions.


title:
Controlling Quasibound States in 1D Continuum Through Electromagnetic
  Induced Transparency Mechanism

abstract:
  We study the coherent scattering process of a single photon confined in an
one-dimensional (1D) coupled cavity-array, where a $\Lambda$-type three-level
atom is placed inside one of the cavities in the array and behaves as a
functional quantum node (FQN). We show that, through the electromagnetic
induced transparency (EIT) mechanism, the $\Lambda$-type FQN bears complete
control over the reflection and transmission of the incident photon along the
cavity-array. We also demonstrate the emergence of a quasibound state of the
single photon inside a secondary cavity constructed by two distant FQN's as two
end mirrors, from which we are motivated to design an all-optical single photon
storage device of quantum coherence.


title: Projection pursuit for discrete data

abstract:
  This paper develops projection pursuit for discrete data using the discrete
Radon transform. Discrete projection pursuit is presented as an exploratory
method for finding informative low dimensional views of data such as binary
vectors, rankings, phylogenetic trees or graphs. We show that for most data
sets, most projections are close to uniform. Thus, informative summaries are
ones deviating from uniformity. Syllabic data from several of Plato's great
works is used to illustrate the methods. Along with some basic distribution
theory, an automated procedure for computing informative projections is
introduced.


title:
Asymptotics of Characteristic Polynomials of Wigner Matrices at the Edge
  of the Spectrum

abstract:
  We investigate the asymptotic behaviour of the second-order correlation
function of the characteristic polynomial of a Hermitian Wigner matrix at the
edge of the spectrum. We show that the suitably rescaled second-order
correlation function is asymptotically given by the Airy kernel, thereby
generalizing the well-known result for the Gaussian Unitary Ensemble (GUE).
Moreover, we obtain similar results for real-symmetric Wigner matrices.


title:
Mixing-induced CP violating sources for electroweak baryogenesis from a
  semiclassical approach

abstract:
  The effects of flavor mixing in electroweak baryogenesis is investigated in a
generalized semiclassical WKB approach. Through calculating the nonadiabatic
corrections to the particle currents it is shown that extra CP violation
sources arise from the off-diagonal part of the equation of motion of particles
moving inside the bubble wall. This type of mixing-induced source is of the
first order in derivative expansion of the Higgs condensate, but is oscillation
suppressed. The numerical importance of the mixing-induced source is discussed
in the Minimal Supersymmetric Standard Model and compared with the source term
induced by semiclassical force. It is found that in a large parameter space
where oscillation suppression is not strong enough, the mixing-induced source
can dominate over that from the semiclassical force.


title: $\rho$-$\omega$ mixing and spin dependent CSV potential

abstract:
  We construct the charge symmetry violating (CSV) nucleon-nucleon potential
induced by the $\rho^0$-$\o$ mixing due to the neutron-proton mass difference
driven by the $NN$ loop. Analytical expression for for the two-body CSV
potential is presented containing both the central and non- central $NN$
interaction. We show that the $\rho$$NN$ tensor interaction can significantly
enhance the charge symmetry violating $NN$ interaction even if momentum
dependent off-shell $\rho^0$-$\omega$ mixing amplitude is considered. It is
also shown that the inclusion of form factors removes the divergence arising
out of the contact interaction. Consequently, we see that the precise size of
the computed scattering length difference depends on how the short range
aspects of the CSV potential are treated.


title: Critical Temperature Curve in the BEC-BCS Crossover

abstract:
  The strongly-correlated regime of the BCS-BEC crossover can be realized by
diluting a system of two-component fermions with a short-range attractive
interaction. We investigate this system via a novel continuous-space-time
diagrammatic determinant Monte Carlo method and determine the universal curve
$T_c/\epsilon_F$ for the transition temperature between the normal and the
superfluid states as a function of the scattering length with the maximum on
the BEC side. At unitarity, we confirm that $T_c/\epsilon_F = 0.152(7)$.


title:
Decay of correlations and invariance principles for dispersing billiards
  with cusps, and related planar billiard flows

abstract:
  Following recent work of Chernov, Markarian, and Zhang, it is known that the
billiard map for dispersing billiards with zero angle cusps has slow decay of
correlations with rate 1/n. Since the collisions inside a cusp occur in quick
succession, it is reasonable to expect a much faster decay rate in continuous
time. In this paper we prove that the flow is rapid mixing: correlations decay
faster than any polynomial rate. A consequence is that the flow admits strong
statistical properties such as the almost sure invariance principle, even
though the billiard map does not.
  The techniques in this paper yield new results for other standard examples in
planar billiards, including Bunimovich flowers and stadia.


title:
Nonlinear c-axis transport in Bi_2Sr_2CaCu_2O_(8+d) from two-barrier
  tunneling

abstract:
  Motivated by the peculiar features observed through intrinsic tunneling
spectroscopy of Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ mesas in the normal state,
we have extended the normal state two-barrier model for the c-axis transport
[M. Giura et al., Phys. Rev. B {\bf 68}, 134505 (2003)] to the analysis of
$dI/dV$ curves. We have found that the purely normal-state model reproduces all
the following experimental features: (a) the parabolic $V$-dependence of
$dI/dV$ in the high-$T$ region (above the conventional pseudogap temperature),
(b) the emergence and the nearly voltage-independent position of the "humps"
from this parabolic behavior lowering the temperature, and (c) the crossing of
the absolute $dI/dV$ curves at a characteristic voltage $V^\times$. Our
findings indicate that conventional tunneling can be at the origin of most of
the uncommon features of the c axis transport in
Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$. We have compared our calculations to
experimental data taken in severely underdoped and slightly underdoped
Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ small mesas. We have found good agreement
between the data and the calculations, without any shift of the calculated
dI/dV on the vertical scale. In particular, in the normal state (above
$T^\ast$) simple tunneling reproduces the experimental dI/dV quantitatively.
Below $T^\ast$ quantitative discrepancies are limited to a simple rescaling of
the voltage in the theoretical curves by a factor $\sim$2. The need for such
modifications remains an open question, that might be connected to a change of
the charge of a fraction of the carriers across the pseudogap opening.


title:
On Decompositions of Lorentz Transformations and their Physical
  Interpretations

abstract:
  In a recent article [1] we have explored alternative decompositions of the
Lorentz transformation by adopting the synchronization convention of the target
frame at the end and alternately at the outset. In this note we develop the
decomposition by assuming a correct universal synchronization that may be
outside the two inertial frames that are involved.


title: Finitude homotopique et isotopique des structures de contact tendues

abstract:
  Let V be a closed 3-manifold. In this paper we prove that the homotopy
classes of plane fields on V that contain tight contact structures are in
finite number and that, if V is atoroidal, the isotopy classes of tight contact
structures are also in finite number.


title:
Radiation Hydrodynamics Scaling Laws in High Energy Density Physics and
  Laboratory Astrophysics

abstract:
  In this paper, radiating fluids scaling laws are studied. We focus on
optically thin and optically thick regimes which are relevant for both
astrophysics and laboratory experiments. By using homothetic Lie groups, we
obtain the scaling laws, the similarity properties and the number of free
parameters which allow to rescale experiments in the two astrophyscial
situations.


title:
Crystal chemistry aspects of the magnetically induced ferroelectricity
  in TbMn2O5 and BiMn2O5

abstract:
  The origin of magnetic frustration was stated and the ions whose shift is
accompanied by emerging magnetic ordering and ferroelectricity in TbMn2O5 and
BiMn2O5 were determined on the basis of calculation of magnetic coupling
parameters by using the structural data. The displacements accompanying the
magnetic ordering are not polar, they just induce changes of bond valence
(charge disordering) of Mn1 and Mn2, thus creating instability of the crystal
structure. To approximate again the bond valence to the initial value (charge
ordering) under magnetic ordering conditions is possible only due to polar
displacement of Mn2 (or O1) and O4 ions along the b axis that is the cause of
ferroelectric transition.


title:
Convergence of dependent walks in a random scenery to fBm-local time
  fractional stable motions

abstract:
  It is classical to approximate the distribution of fractional Brownian motion
by a renormalized sum $ S_n $ of dependent Gaussian random variables. In this
paper we consider such a walk $ Z_n $ that collects random rewards $ \xi_j $
for $ j \in \mathbb Z,$ when the ceiling of the walk $ S_n $ is located at $
j.$ The random reward (or scenery) $ \xi_j $ is independent of the walk and
with heavy tail. We show the convergence of the sum of independent copies of $
Z_n$ suitably renormalized to a stable motion with integral representation,
whose kernel is the local time of a fractional Brownian motion (fBm). This work
extends a previous work where the random walk $ S_n$ had independent increments
limits.


title:
Magnetic field induced confinement-deconfinement transition in graphene
  quantum dots

abstract:
  Massless Dirac particles cannot be confined by an electrostatic potential.
This is a problem for making graphene quantum dots but confinement can be
achieved with a magnetic field and here, general conditions for confined and
deconfined states are derived. There is a class of potentials for which the
character of the state can be controlled at will. Then a
confinement-deconfinement transition occurs which allows the Klein paradox to
be probed experimentally in graphene dots.


title: Entanglement Trapping in Structured Environments

abstract:
  The entanglement dynamics of two independent qubits each embedded in a
structured environment under conditions of inhibition of spontaneous emission
is analyzed, showing entanglement trapping. We demonstrate that entanglement
trapping can be used efficiently to prevent entanglement sudden death. For the
case of realistic photonic band-gap materials, we show that high values of
entanglement trapping can be achieved. This result is of both fundamental and
applicative interest since it provides a physical situation where the
entanglement can be preserved and manipulated, e.g. by Stark-shifting the qubit
transition frequency outside and inside the gap.


title: A theory of ferromagnetism by Ettore Majorana

abstract:
  We present and analyze in detail an unknown theory of ferromagnetism
developed by Ettore Majorana as early as the beginnings of 1930s, substantially
different in the methods employed from the well-known Heisenberg theory of 1928
(and from later formulations by Bloch and others). Similarly to this, however,
it describes successfully the main features of ferromagnetism, although the key
equation for the spontaneous mean magnetization and the expression for the
Curie temperature are different from those deduced in the Heisenberg theory
(and in the original phenomenological Weiss theory). The theory presented here
contains also a peculiar prediction for the number of nearest neighbors
required to realize ferromagnetism, which avoids the corresponding arbitrary
assumption made by Heisenberg on the basis of known (at that time) experimental
observations. Some applications of the theory (linear chain, triangular chain,
etc.) are, as well, considered.


title: A New Structural Property of SAT

abstract:
  We review a minimum set of notions from our previous paper on structural
properties of SAT at arXiv:0802.1790 that will allow us to define and discuss
the "complete internal independence" of a decision problem. This property is
strictly stronger than the independence property that was called "strong
internal independence" in cited paper. We show that SAT exhibits this property.
We argue that this form of independence of a decision problem is the strongest
possible for a problem. By relying upon this maximally strong form of internal
independence, we reformulate in more strict terms the informal remarks on
possible exponentiality of SAT that concluded our previous paper. The net
result of that reformulation is a hint for a proof for SAT being exponential.
We conjecture that a complete proof of that proposition can be obtained by
strictly following the line of given hint of proof.


title:
Fuzzy Feedback Scheduling of Resource-Constrained Embedded Control
  Systems

abstract:
  The quality of control (QoC) of a resource-constrained embedded control
system may be jeopardized in dynamic environments with variable workload. This
gives rise to the increasing demand of co-design of control and scheduling. To
deal with uncertainties in resource availability, a fuzzy feedback scheduling
(FFS) scheme is proposed in this paper. Within the framework of feedback
scheduling, the sampling periods of control loops are dynamically adjusted
using the fuzzy control technique. The feedback scheduler provides QoC
guarantees in dynamic environments through maintaining the CPU utilization at a
desired level. The framework and design methodology of the proposed FFS scheme
are described in detail. A simplified mobile robot target tracking system is
investigated as a case study to demonstrate the effectiveness of the proposed
FFS scheme. The scheme is independent of task execution times, robust to
measurement noises, and easy to implement, while incurring only a small
overhead.


title: Postulates for measures of genuine multipartite correlations

abstract:
  A lot of research has been done on multipartite correlations. However, it
seems strange that there is no definition of so called genuine multipartite
correlations. In this paper we propose three reasonable postulates which each
measure or indicator of genuine multipartite correlations (or genuine
multipartite entanglement) should satisfy. We also introduce degree of
correlations which gives partial characterization of multipartite correlations.
Then, we show that covariance does not satisfy two postulates and hence, it
cannot be used as an indicator of genuine multipartite correlations. Finally,
we propose candidate for a measure of genuine multipartite correlations based
on the work that can be drawn from local bath by means of a multipartite state.


title: Detecting Double Beta Decays Using Nuclear Emulsions

abstract:
  Neutrino nature and absolute mass scale are major questions in particle
physics which cannot be addressed by the present neutrino oscillation program.
To answer these two questions, several neutrinoless double beta decay
experiments are underway or planed for the near future. These experiments,
mainly use bolometric techniques or gaseous counters coupled with scintillator
detectors. The energy resolution is better in bolometric experiments but
experiments coupling tracking with calorimetry have the advantage of observing
the two electron tracks and remove many background sources. Here, we present a
proposal of using nuclear emulsions to observe double beta decays. This
technique has the advantage of precise tracking and vertexing even for low
energy electrons.


title: Neural Feedback Scheduling of Real-Time Control Tasks

abstract:
  Many embedded real-time control systems suffer from resource constraints and
dynamic workload variations. Although optimal feedback scheduling schemes are
in principle capable of maximizing the overall control performance of
multitasking control systems, most of them induce excessively large
computational overheads associated with the mathematical optimization routines
involved and hence are not directly applicable to practical systems. To
optimize the overall control performance while minimizing the overhead of
feedback scheduling, this paper proposes an efficient feedback scheduling
scheme based on feedforward neural networks. Using the optimal solutions
obtained offline by mathematical optimization methods, a back-propagation (BP)
neural network is designed to adapt online the sampling periods of concurrent
control tasks with respect to changes in computing resource availability.
Numerical simulation results show that the proposed scheme can reduce the
computational overhead significantly while delivering almost the same overall
control performance as compared to optimal feedback scheduling.


title:
NNLO QCD contributions to the flavor non-singlet sector of ${\bf
  {F_2(x,Q^2)}}$

abstract:
  We present the results of our QCD analysis for nonsinglet unpolarized quark
distributions and structure function $F_2(x,Q^2)$. New parameterizations are
derived for the nonsinglet quark distributions for the kinematic wide range of
$x$ and $Q^2$. The analysis is based on the Jacobi polynomials expansion of the
structure function. The higher twist contributions of proton and deuteron
structure function are obtained in the large $x$ region. Our calculations for
nonsinglet unpolarized quark distribution functions based on the Jacobi
polynomials method are in good agreement with the other theoretical models. The
values of $\Lambda_{QCD}$ and $\alpha_s(M_z^2)$ are determined.


title: Objective Bayesian analysis under sequential experimentation

abstract:
  Objective priors for sequential experiments are considered. Common priors,
such as the Jeffreys prior and the reference prior, will typically depend on
the stopping rule used for the sequential experiment. New expressions for
reference priors are obtained in various contexts, and computational issues
involving such priors are considered.


title:
Temperature Correction to Casimir-Lifshitz Free Energy at Low
  Temperatures: Semiconductors

abstract:
  The Casimir force and free energy at low temperatures has been the subject of
focus for some time. We calculate the temperature correction to the
Casimir-Lifshitz free energy between two parallel plates made of dielectric
material possessing a constant conductivity at low temperatures, described
through a Drude-type dielectric function. For the transverse magnetic (TM) mode
such a calculation is new. A further calculation for the case of the TE mode is
thereafter presented which extends and generalizes previous work for metals. A
numerical study is undertaken to verify the correctness of the analytic
results.