title: Disorder-induced superfluidity

abstract:
  We use quantum Monte Carlo simulations to study the phase diagram of
hard-core bosons with short-ranged {\it attractive} interactions, in the
presence of uniform diagonal disorder. It is shown that moderate disorder
stabilizes a glassy superfluid phase in a range of values of the attractive
interaction for which the system is a Mott insulator, in the absence of
disorder. A transition to an insulating Bose glass phase occurs as the strength
of the disorder or interactions increases.


title:
Baryon resonances in the mean field approach and a simple explanation of
  the Theta+ pentaquark

abstract:
  We suggest to classify baryon resonances as single-quark states in a mean
field, and/or as its collective excitations. Identifying the Roper resonance
N(1440), the nucleon resonance N(1535), and the singlet hyperon Lambda(1405) as
single-quark excitations, we find that there must be an exotic S=+1 baryon
resonance Theta+ (the "pentaquark") with a mass about 1440+1535-1405=1570 MeV
and spin-parity one-half-plus. We argue that Theta+ is an analog of the
Gamov--Teller excitation long known in nuclear physics.


title: Possible treatment of the Ghost states in the Lee-Wick Standard Model

abstract:
  Very recently, the Lee-Wick standard model has been introduced as a non-SUSY
extension of the Standard model which solves the Hierarchy problem. In this
model, each field kinetic term attains a higher derivative term. Like any
Lee-Wick theory, this model suffers from existence of Ghost states. In this
work, we consider a prototype scalar field theory with its kinetic term has a
higher derivative term, which mimics the scalar sector in the Lee-Wick Standard
model. We introduced an imaginary auxiliary field to have an equivalent
non-Hermitian two-field scalar field theory. We were able to calculate the
positive definite metric operator $\eta$ in quantum mechanical and quantum
field versions of the theory in a closed form. While the Hamiltonian is
non-Hermitian in a Hilbert space with the Dirac sense inner product, it is
Hermitian in a Hilbert space endowed by the inner product $<n|\eta|m>$ as well
as having a correct-sign propagator (no Lee-Wick fields). Besides, the obtained
metric operator also diagonalizes the Hamiltonian in the two fields (no
mixing). Moreover, the Hermiticity of $\eta$ constrained the two Higgs masses
to be related as $M>2m$, which has been obtained in another work using a very
different regime and thus supports our calculation. Also, an equivalent
Hermitian (in the Dirac sense) Hamiltonian is obtained which has no Ghost
states at all, which is a forward step to make the Lee-Wick theories more
popular among the Physicists.


title:
The antiferromagnetic spin-1/2 Heisenberg model on the square lattice in
  a magnetic field

abstract:
  We study the field dependence of the antiferromagnetic spin-1/2 Heisenberg
model on the square lattice by means of exact diagonalizations. In a first
part, we calculate the spin-wave velocity, the spin-stiffness, and the magnetic
susceptibility and thus determine the microscopic parameters of the low-energy
long-wavelength description. In a second part, we present a comprehensive study
of dynamical spin correlation functions for magnetic fields ranging from zero
up to saturation. We find that at low fields, magnons are well defined in the
whole Brillouin zone, but the dispersion is substantially modified by quantum
fluctuations compared to the classical spectrum. At higher fields, decay
channels open and magnons become unstable with respect to multi-magnon
scattering. Our results directly apply to inelastic neutron scattering
experiments.


title: Brane inflation revisited after WMAP five-year results

abstract:
  In this paper, we revisit brane inflation models with the WMAP five-year
results. The WMAP five-year data favor a red-tilted power spectrum of
primordial fluctuations at the level of two standard deviations, which is the
same as the WMAP three-year result qualitatively, but quantitatively the
spectral index is slightly greater than the three-year value. This result can
bring impacts on brane inflation models. According to the WMAP five-year data,
we find that the KKLMMT model can survive at the level of one standard
deviation, and the fine-tuning of the parameter $\beta$ can be alleviated to a
certain extent at the level of two standard deviations.


title: Function Spaces Related to the Dirichlet Space

abstract:
  We present results about spaces of holomorphic functions associated to the
classical Dirichlet space. The spaces we consider have roles similar to the
roles of $H^{1}$ and $BMO$ in the Hardy space theory and we emphasize those
analogies.


title: New Non-Trivial Vacuum Structures in Supersymmetric Field Theories

abstract:
  In this talk, we present three examples of new non-trivial vacuum structures
that can occur in supersymmetric field theories, along with explicit models in
which they arise. The first vacuum structure is one in which supersymmetry is
broken at tree-level in a perturbative theory that also contains a
supersymmetry-preserving ground state. Models realizing this structure are
uniquely characterized by the fact that no flat directions appear in the
classical potential, all vacua appear at finite distances in field space, and
no non-perturbative physics is required for vacuum stability. The second
non-trivial vacuum structure we discuss consists of large (and even infinite)
towers of metastable vacua, and we show that models which give rise to such
vacuum towers exhibit a rich set of instanton-induced vacuum tunneling
dynamics. Finally, our third new non-trivial vacuum structure consists of an
infinite number of degenerate vacua; this leads to a Bloch-wave ground state
and a vacuum "band" structure. Models with such characteristics therefore
experience time-dependent vacuum oscillations. Needless to say, these novel
vacuum structures lead to many new potential applications for supersymmetric
field theories, ranging from the cosmological-constant problem to the string
landscape, supersymmetry breaking, and Z' phenomenology.


title: On higher dimensional black holes with abelian isometry group

abstract:
  We consider (n+1)--dimensional, stationary, asymptotically flat, or
Kaluza-Klein asymptotically flat black holes, with an abelian $s$--dimensional
subgroup of the isometry group satisfying an orthogonal integrability
condition. Under suitable regularity conditions we prove that the area of the
group orbits is positive on the domain of outer communications, vanishing only
on its boundary and on the "symmetry axis". We further show that the orbits of
the connected component of the isometry group are timelike throughout the
domain of outer communications. Those results provide a starting point for the
classification of such black holes. Finally, we show non-existence of zeros of
static Killing vectors on degenerate Killing horizons, as needed for the
generalisation of the static no-hair theorem to higher dimensions.


title: Random Organization and Plastic Depinning

abstract:
  We provide evidence that plastic depinning falls into the same class of
phenomena as the random organization which was recently studied in periodically
driven particle systems [L. Corte et al., Nature Phys. 4, 420 (2008)]. In the
plastic flow system, the pinned regime corresponds to the quiescent state and
the moving state corresponds to the fluctuating state. When an external force
is suddenly applied, the system eventually organizes into one of these two
states with a time scale that diverges as a power law at a nonequilibrium
transition. We propose a simple experiment to test for this transition in
colloidal systems and superconducting vortex systems with random disorder.


title:
Topological Methods for Exploring Low-density States in Biomolecular
  Folding Pathways

abstract:
  Characterization of transient intermediate or transition states is crucial
for the description of biomolecular folding pathways, which is however
difficult in both experiments and computer simulations. Such transient states
are typically of low population in simulation samples. Even for simple systems
such as RNA hairpins, recently there are mounting debates over the existence of
multiple intermediate states. In this paper, we develop a computational
approach to explore the relatively low populated transition or intermediate
states in biomolecular folding pathways, based on a topological data analysis
tool, Mapper, with simulation data from large-scale distributed computing. The
method is inspired by the classical Morse theory in mathematics which
characterizes the topology of high dimensional shapes via some functional level
sets. In this paper we exploit a conditional density filter which enables us to
focus on the structures on pathways, followed by clustering analysis on its
level sets, which helps separate low populated intermediates from high
populated uninteresting structures. A successful application of this method is
given on a motivating example, a RNA hairpin with GCAA tetraloop, where we are
able to provide structural evidence from computer simulations on the multiple
intermediate states and exhibit different pictures about unfolding and
refolding pathways. The method is effective in dealing with high degree of
heterogeneity in distribution, capturing structural features in multiple
pathways, and being less sensitive to the distance metric than nonlinear
dimensionality reduction or geometric embedding methods. It provides us a
systematic tool to explore the low density intermediate states in complex
biomolecular folding systems.


title:
A uniqueness result on ordinary differential equations with singular
  coefficients

abstract:
  We consider the uniqueness of solutions of ordinary differential equations
where the coefficients may have singularities. We derive upper bounds on the
the order of singularities of the coefficients and provide examples to
illustrate the results.


title: Quantum Exchangeable Sequences of Algebras

abstract:
  We extend the notion of quantum exchangeability, introduced by K\"ostler and
Speicher in arXiv:0807.0677, to sequences (\rho_1,\rho_2,...c) of homomorphisms
from an algebra C into a noncommutative probability space (A,\phi), and prove a
free de Finetti theorem: an infinite quantum exchangeable sequence
(\rho_1,\rho_2,...c) is freely independent and identically distributed with
respect to a conditional expectation. As a corollary we obtain a free analogue
of the Hewitt Savage zero-one law.
  As in the classical case, the theorem fails for finite sequences. We give a
characterization of finite quantum exchangeable sequences, which can be viewed
as a noncommutative analogue of sampling without replacement. We then give an
approximation to how far a finite quantum exchangeable sequence is from being
freely independent with amalgamation.


title:
Quantum Predictive Learning and Communication Complexity with Single
  Input

abstract:
  We define a new model of quantum learning that we call Predictive Quantum
(PQ). This is a quantum analogue of PAC, where during the testing phase the
student is only required to answer a polynomial number of testing queries.
  We demonstrate a relational concept class that is efficiently learnable in
PQ, while in any "reasonable" classical model exponential amount of training
data would be required. This is the first unconditional separation between
quantum and classical learning.
  We show that our separation is the best possible in several ways; in
particular, there is no analogous result for a functional class, as well as for
several weaker versions of quantum learning. In order to demonstrate tightness
of our separation we consider a special case of one-way communication that we
call single-input mode, where Bob receives no input. Somewhat surprisingly,
this setting becomes nontrivial when relational communication tasks are
considered. In particular, any problem with two-sided input can be transformed
into a single-input relational problem of equal classical one-way cost. We show
that the situation is different in the quantum case, where the same
transformation can make the communication complexity exponentially larger. This
happens if and only if the original problem has exponential gap between quantum
and classical one-way communication costs. We believe that these auxiliary
results might be of independent interest.


title:
Finite-size and confinement effects in spin-polarized trapped Fermi
  gases

abstract:
  We calculate the energy of a single fermion interacting resonantly with a
Fermi sea of different-species fermions in asymmetric traps, and show that
finite particle numbers and the trap geometry impact the phase structure and
the critical polarization. Our findings contribute to understanding some
experimental discrepancies in spin-polarized Fermi gases as finite-size and
confinement effects.

categories: cond-mat.other cond-mat.supr-con hep-ph nucl-th


title:
The projectively resolving of some classes over a direct product of
  rings

abstract:
  In this paper, we study the resolving of $\mathcal{SGP}(-)$ and
$\mathcal{SGF}(-)$, the classes of all strongly Gorenstein projective and flat
modules respectively, over a direct product of commutative rings.


title:
Unusual features of coarsening with detachment rates decreasing with
  cluster mass

abstract:
  We study conserved one-dimensional models of particle diffusion, attachment
and detachment from clusters, where the detachment rates decrease with
increasing cluster size as gamma(m) ~ m^{-k}, k>0. Heuristic scaling arguments
based on random walk properties show that the typical cluster size scales as
(t/ln(t))^z, with z=1/(k+2). The initial symmetric flux of particles between
neighboring clusters is followed by an effectively assymmetric flux due to the
unbalanced detachement rates, which leads to the above logarithmic correction.
Small clusters have densities of order t^{-mz(1)}, with z(1) = k/(k+2). Thus,
for k<1, the small clusters (mass of order unity) are statistically dominant
and the average cluster size does not scale as the size of typically large
clusters does. We also solve the Master equation of the model under an
independent interval approximation, which yields cluster distributions and
exponent relations and gives the correct dominant coarsening exponent after
accounting for the effects of correlations. The coarsening of large clusters is
described by the distribution P_t(m) ~ 1/t^y f(m/t^z), with y=2z. All results
are confirmed by simulation, which also illustrates the unusual features of
cluster size distributions, with a power law decay for small masses and a
negatively skewed peak in the scaling region. The detachment rates considered
here can apply in the presence of strong attractive interactions, and recent
applications suggest that even more rapid rate decays are also physically
realistic.


title: SK1 for graded division algebras

abstract:
  The reduced Whitehead group $\SK$ of a graded division algebra graded by a
torsion-free abelian group is studied. It is observed that the computations
here are much more straightforward than in the non-graded setting. Bridges to
the ungraded case are then established by the following two theorems: It is
proved that $\SK$ of a tame valued division algebra over a henselian field
coincides with $\SK$ of its associated graded division algebra. Furthermore, it
is shown that $\SK$ of a graded division algebra is isomorphic to $\SK$ of its
quotient division algebra. The first theorem gives the established formulas for
the reduced Whitehead group of certain valued division algebras in a unified
manner, whereas the latter theorem covers the stability of reduced Whitehead
groups, and also describes $\SK$ for generic abelian crossed products.


title: Priority Arguments and Epsilon Substitutions

abstract:
  Kreisel has observed that the termination proof for Hilbert's
epsilon-substitution method bears a resemblance to the priority arguments used
in recursion theory. We make this precise by proving the termination using a
framework for priority arguments due to Lerman and Lempp.


title: On maximal Subgroups of the multiplicative group of a division algebra

abstract:
  The question of existence of a maximal subgroup in the multiplicative group
D* of a division algebra D finite dimensional over its center F is
investigated. We prove that if D* has no maximal subgroup, then deg(D) is not a
power of 2, F^{*2} is divisible, and for each odd prime p dividing deg(D),
there exist noncyclic division algebras of degree p over F.


title:
Extending the isolated horizon phase space to string-inspired gravity
  models

abstract:
  An isolated horizon (IH) is a null hypersurface at which the geometry is held
fixed. This generalizes the notion of an event horizon so that the black hole
is an object that is in local equilibrium with its (possibly) dynamic
environment. The first law of IH mechanics that arises from the framework
relates quantities that are all defined at the horizon.
  IHs have been extensively studied in Einstein gravity with various matter
couplings and rotation, and in asymptotically flat and asymptotically anti-de
Sitter (ADS) spacetimes in all dimensions $D\geq3$. Motivated by the
nonuniqueness of black holes in higher dimensions and by the black-hole/string
correspondence principle, we devote this thesis to the extension of the
framework to include IHs in string-inspired gravity models, specifically to
Einstein-Maxwell-Chern-Simons (EMCS) theory and to Einstein-Gauss-Bonnet (EGB)
theory in higher dimensions.
  The focus is on determining the generic features of black holes that are
solutions to the field equations of the theories under consideration. We obtain
various results for non-extremal, extremal and supersymmetric IHs in EM-CS
theory, and for non-rotating IHs in EGB theory.
  (An extended abstract is given in the PDF file.)


title: Does the Universe Have a Handedness?

abstract:
  In this article I extend an earlier study of spiral galaxies in the Sloan
Digital Sky Survey (SDSS) to investigate whether the universe has an overall
handedness. A preference for spiral galaxies in one sector of the sky to be
left-handed or right-handed spirals would indicate a parity-violating asymmetry
in the overall universe and a preferred axis. The previous study used 2616
spiral galaxies with redshifts <0.04 and identified handedness. The new study
uses 15872 with redshifts <0.085 and obtains very similar results to the first
with a signal exceeding 5 sigma, corresponding to a probability of 2.5x10-7 for
occurring by chance. The axis of the dipole asymmetry lies at approx. (l, b)
=(32d,69d), roughly along that of our Galaxy and close to the so-called "Axis
of Evil".


title: De Sitter Special Relativity: Effects on Cosmology

abstract:
  The main consequences of de Sitter Special Relativity to the Standard
Cosmological Model of Physical Cosmology are examined. The cosmological
constant Lambda appears, in this theory, as a manifestation of the proper
conformal current, which must be added to the usual energy-momentum density. As
that conformal current itself vanishes in absence of sources, Lambda is
ultimately dependent on the matter content, and can in principle be calculated.
A present-day value very close to that given by the crossed supernova/BBR data
is obtained through simple and reasonable approximations. Also a primeval
inflation of polynomial type is found, and the usual notion of co-moving
observer is slightly modified.


title: Stable higher-charge discrete vortices in hexagonal optical lattices

abstract:
  We show that double-charge discrete optical vortices may be completely stable
in hexagonal photonic lattices where single-charge vortices always exhibit
dynamical instabilities. Even when unstable the double-charge vortices
typically have a much weaker instability than the single-charge vortices, and
thus their breakup occurs at longer propagation distances.


title: Generalized Moonshine I: Genus zero functions

abstract:
  We introduce a notion of Hecke-monicity for functions on certain moduli
spaces associated to torsors of finite groups over elliptic curves, and show
that it implies strong invariance properties under linear fractional
transformations. Specifically, if a weakly Hecke-monic function has algebraic
integer coefficients and a pole at infinity, then it is either a holomorphic
genus-zero function invariant under a congruence group or of a certain
degenerate type. As a special case, we prove the same conclusion for replicable
functions of finite order, which were introduced by Conway and Norton in the
context of monstrous moonshine. As an application, we introduce a class of Lie
algebras with group actions, and show that the characters derived from them are
weakly Hecke-monic. When the Lie algebras come from chiral conformal field
theory in a certain sense, then the characters form holomorphic genus-zero
functions invariant under a congruence group.


title: Higher order spectral shift

abstract:
  We construct higher order spectral shift functions, extending the
perturbation theory results of M. G. Krein and L. S. Koplienko on
representations for the remainders of the first and second order Taylor-type
approximations of operator functions. The higher order spectral shift functions
represent the remainders of higher order Taylor-type approximations; they can
be expressed recursively via the lower order (in particular, Krein's and
Koplienko's) ones. We also obtain higher order spectral averaging formulas
generalizing the Birman-Solomyak spectral averaging formula. The results are
obtained in the semi-finite von Neumann algebra setting, with the perturbation
taken in the Hilbert-Schmidt class of the algebra.


title: Micro Black Holes and the Democratic Transition

abstract:
  Unitarity implies that the evaporation of microscopic quasi-classical black
holes cannot be universal in different particle species. This creates a puzzle,
since it conflicts with the thermal nature of quasi-classical black holes,
according to which all the species should see the same horizon and be produced
with the same Hawking temperatures. We resolve this puzzle by showing that for
the microscopic black holes, on top the usual quantum evaporation time, there
is a new time-scale which characterizes a purely classical process during which
the black hole looses the ability to differentiate among the species, and
becomes democratic. We demonstrate this phenomenon in a well-understood
framework of large extra dimensions, with a number of parallel branes. An
initially non-democratic black hole is the one localized on one of the branes,
with its high-dimensional Schwarzschild radius being much shorter than the
interbrane distance. Such a black hole seemingly cannot evaporate into the
species localized on the other branes, that are beyond its reach. We
demonstrate that in reality the system evolves classically in time, in such a
way that the black hole accretes the neighboring branes. The end result is a
completely democratic static configuration, in which all the branes share the
same black hole, and all the species are produced with the same Hawking
temperature. Thus, just like their macroscopic counterparts, the microscopic
black holes are universal bridges to the hidden sector physics.


title: SK1 of Azumaya algebras over hensel pairs

abstract:
  Let A be an Azumaya algebra of constant rank n^2 over a Hensel pair (R,I)
where R is a semilocal ring with n invertible in R. Then the reduced Whitehead
group SK(A) coincides with its reduction SK(A/IA).


title:
Evolution of Magnetic Fields in High Mass Star Formation: SMA dust
  polarization image of the UCHII region G5.89-0.39

abstract:
  We report high angular resolution (3") Submillimeter Array (SMA) observations
of the molecular cloud associated with the Ultra-Compact HII region G5.89-0.39.
Imaged dust continuum emission at 870 micron reveals significant linear
polarization. The position angles (PAs) of the polarization vary enormously but
smoothly in a region of 2x10^4 AU. Based on the distribution of the PAs and the
associated structures, the polarized emission can be separated roughly into two
components. The component "x" is associated with a well defined dust ridge at
870 micron, and is likely tracing a compressed B field. The component "o" is
located at the periphery of the dust ridge and is probably from the original B
field associated with a pre-existing extended structure. The global B field
morphology in G5.89, as inferred from the PAs, is clearly disturbed by the
expansion of the HII region and the molecular outflows. Using the
Chandrasekhar-Fermi method, we estimate from the smoothness of the field
structures that the B field strength in the plane of sky can be no more than
2-3 mG. We then compare the energy densities in the radiation, the B field, and
the mechanical motions as deduced from the C^17O 3-2 line emission. We conclude
that the B field structures are already overwhelmed and dominated by the
radiation, outflows, and turbulence from the newly formed massive stars.


title: Edge states of Spin-1/2 Two-Leg Ladder with Four-Spin Ring Exchange

abstract:
  A topological insulator and its spin analogue as a gapped spin liquid have
characteristic low energy excitations (edge states) within the gap when the
systems have boundaries. This is the bulk-edge correspondence, which implies
that the edge states themselves characterize the gapped bulk spin liquid. Based
on the general principle, we analyzed the vector chirality phase of the
spin-1/2 ladder with ring exchange by using the edge states and the
entanglement entropy.


title:
Spitzer--IRAC Imagery and Photometry of Ultracompact HII Regions With
  Extended Emission

abstract:
  We present the results of a morphological study performed to a sample of
Ultracompact (UC) HII regions with Extended Emission (EE) using Spitzer--IRAC
imagery and 3.6 cm VLA conf. D radio-continuum (RC) maps. Some examples of the
comparison between maps and images are presented. Usually there is an IR point
source counterpart to the peak(s) of RC emission, at the position of the UC
source. We find that the predominant EE morphology is the cometary, and in most
cases is coincident with IR emission at 8.0 $\mu$m. Preliminary results of
Spitzer--IRAC photometry of a sub-sample of 13 UC HII regions with EE based on
GLIMPSE legacy data are also presented. Besides, individual IRAC photometry was
performed to 19 UC sources within these 13 regions. We show that UC sources lie
on specific locus, both in IRAC color-color and AM-product diagnostic diagrams.
Counts of young stellar sources are presented for each region, and we conclude
that a proportion of ~ 2%, ~10%, and ~88% of sources in the UC HII regions with
EE are, in average, Class I, II, and III, respectively.


title:
Completion Time Minimization and Robust Power Control in Wireless Packet
  Networks

abstract:
  A wireless packet network is considered in which each user transmits a stream
of packets to its destination. The transmit power of each user interferes with
the transmission of all other users. A convex cost function of the completion
times of the user packets is minimized by optimally allocating the users'
transmission power subject to their respective power constraints. At all ranges
of SINR, completion time minimization can be formulated as a convex
optimization problem and hence can be efficiently solved. In particular,
although the feasible rate region of the wireless network is non-convex, its
corresponding completion time region is shown to be convex. When channel
knowledge is imperfect, robust power control is considered based on the channel
fading distribution subject to outage probability constraints. The problem is
shown to be convex when the fading distribution is log-concave in exponentiated
channel power gains; e.g., when each user is under independent Rayleigh,
Nakagami, or log-normal fading. Applying the optimization frameworks in a
wireless cellular network, the average completion time is significantly reduced
as compared to full power transmission.


title: Degenerate weakly nonlinear elastic plane waves

abstract:
  Weakly nonlinear plane waves are considered in hyperelastic crystals.
Evolution equations are derived at a quadratically nonlinear level for the
amplitudes of quasi-longitudinal and quasi-transverse waves propagating in
arbitrary anisotropic media. The form of the equations obtained depends upon
the direction of propagation relative to the crystal axes. A single equation is
found for all propagation directions for quasi-longitudinal waves, but a pair
of coupled equations occurs for quasi-transverse waves propagating along
directions of degeneracy, or acoustic axes. The coupled equations involve four
material parameters but they simplify if the wave propagates along an axis of
material symmetry. Thus, only two parameters arise for propagation along an
axis of two-fold symmetry, and one for a three-fold axis. The transverse wave
equations decouple if the axis is four-fold or higher. In the absence of a
symmetry axis it is possible that the evolution equations of the
quasi-transverse waves decouple if the third order elastic moduli satisfy a
certain identity. The theoretical results are illustrated with explicit
examples.


title: Large N QCD in two dimensions with a baryonic chemical potential

abstract:
  We consider large N gauge theory on a two dimensional lattice in the presence
of a baryonic chemical potential. We work with one copy of naive fermion and
argue that reduction holds even in the presence of a chemical potential.
Analytical arguments supported by numerical studies show that there is no phase
transition as a function of the baryonic chemical potential.


title: Seeing Anderson Localization

abstract:
  Anderson localization was discovered 50 years ago to describe the propagation
of electrons in the presence of disorder. The main prediction back then, was
the existence of disorder induced localized states, which do not conduct
electricity. Many years later it turns out, that the concept of Anderson
localization is much more general and applies to almost any type of propagation
in time or space, when more than one parameter is relevant (like phase and
amplitude). Here we propose a new optical scheme to literally see Anderson
localization by varying the optical wavelength or angle of incidence to tune
between localized and delocalized states. The occurrence of Anderson
localization in the propagation of light, in particular, has become the focus
of tremendous interest due to the emergence of new optical technologies and
media, such as low dimensional and disordered optical lattices. While several
experiments have reported the measurement of Anderson localization of light,
many of the observations remain controversial because the effects of absorption
and localization have a similar signature, i.e., exponential decrease of the
transmission with the system size. In this work, we discuss a system, where we
can clearly differentiate between absorption and localization effects because
this system is equivalent to a perfect filter, only in the absence of any
absorption. Indeed, only one wavelength is perfectly transmitted and all others
are fully localized. These results were obtained by developing a new
theoretical framework for the average optical transmission through disordered
media.


title: Shattering and coagulation of dust grains in interstellar turbulence

abstract:
  We investigate shattering and coagulation of dust grains in turbulent
interstellar medium (ISM). The typical velocity of dust grain as a function of
grain size has been calculated for various ISM phases based on a theory of
grain dynamics in compressible magnetohydrodynamic turbulence. In this paper,
we develop a scheme of grain shattering and coagulation and apply it to
turbulent ISM by using the grain velocities predicted by the above turbulence
theory. Since large grains tend to acquire large velocity dispersions as shown
by earlier studies, large grains tend to be shattered. Large shattering effects
are indeed seen in warm ionized medium (WIM) within a few Myr for grains with
radius $a\ga 10^{-6}$ cm. We also show that shattering in warm neutral medium
(WNM) can limit the largest grain size in ISM ($a\sim 2\times 10^{-5}
\mathrm{cm}$). On the other hand, coagulation tends to modify small grains
since it only occurs when the grain velocity is small enough. Coagulation
significantly modifies the grain size distribution in dense clouds (DC), where
a large fraction of the grains with $a<10^{-6}$ cm coagulate in 10 Myr. In
fact, the correlation among $R_V$, the carbon bump strength, and the
ultraviolet slope in the observed Milky Way extinction curves can be explained
by the coagulation in DC. It is possible that the grain size distribution in
the Milky Way is determined by a combination of all the above effects of
shattering and coagulation. Considering that shattering and coagulation in
turbulence are effective if dust-to-gas ratio is typically more than $\sim
1/10$ of the Galactic value, the regulation mechanism of grain size
distribution should be different between metal-poor and metal-rich
environments.


title: Coherent exciton transport and trapping on long-range interacting cycles

abstract:
  We consider coherent exciton transport modeled by continuous-time quantum
walks (CTQWs) on long-range interacting cycles (LRICs), which are constructed
by connecting all the two nodes of distance $m$ in the cycle graph. LRIC has a
symmetric structure and can be regarded as the extensions of the cycle graph
(nearest-neighboring lattice). For small values of $m$, the classical and
quantum return probabilities show power law behavior $p(t)\sim t^{-0.5}$ and
$\pi(t)\sim t^{-1}$, respectively. However, for large values of $m$, the
classical and quantum efficiency scales as $p(t)\sim t^{-1}$ and $\pi(t)\sim
t^{-2}$. We give a theoretical explanation of this transition using the method
of stationary phase approximation (SPA). In the long time limit, depending on
the network size $N$ and parameter $m$, the limiting probability distributions
of quantum transport show various patterns. When the network size $N$ is an
even number, we find an asymmetric transition probability of quantum transport
between the initial node and its opposite node. This asymmetry depends on the
precise values of $N$ and $m$. Finally, we study the transport processes in the
presence of traps and find that the survival probability decays faster on
networks of large $m$.


title:
Small Neutrino Masses From Structural cancellation In Left-Right
  Symmetric Model

abstract:
  The Type I, II and hybrid (I+II) seesaw mechanism, which explain why
neutrinos are especially light, are consequences of the left-right symmetric
model (LRSM). They can be classified by the ranges of parameters of LRSM. We
show that a nearly cancellation in general Type-(I+II) seesaw is more natural
than other types of seesaw in the LRSM if we consider their stability against
radiative correction. In this scenario the small neutrino masses are due to the
structure cancellation, and the masses of the right handed neutrino can be of
order of O(10)TeV. The realistic model for non-zero neutrino masses, charged
lepton masses and lepton tribimaximal mixing can be implemented by embedding
$A_4$ flavor symmetry in the model with perturbations to the textures.


title: Kodaira-Iitaka Dimension on a Normal Prime Divisor

abstract:
  This paper was inspired by work by T. Peternell, M. Schneider and A.J.
Sommese on the Kodaira dimension of subvarieties. In it I find a relation
between the Kodaira-Iitaka dimension of a divisor on a normal variety and that
of related divisors on an irreducible normal subvariety of codimension one. The
main result may be stated in a simplified form as: For $X$ a complete normal
variety, $Y \sub X$ an irreducible complete normal divisor and $\sL$ an
invertible sheaf on $X$, there exist integers $n_1 > 0, n_2 \geq 0$ for which
$\kappa(X,\sL) - 1 \leq \kappa(Y,\sL^{n_1}(-n_2Y)|_Y)$, where, if $Y$ is not a
fixed component of large tensor powers of $\sL$, we may take $n_1 >> n_2$. This
has implications for Kodaira-Iitaka dimension on a subvariety of any
codimension.


title: Spectropolarimetry of SNR G296.5+10.0

abstract:
  Radio continuum emission from the supernova remnant G296.5+10.0 was observed
using the Australia Telescope Compact Array. Using a 104 MHz bandwidth split
into 13 x 8 MHz spectral channels, it was possible to produce a pixel-by-pixel
image of Rotation Measure (RM) across the entire remnant. A lack of correlation
between RM and X-ray surface brightness reveals that the RMs originate from
outside the remnant. Using this information, we will characterise the smooth
component of the magnetic field within the supernova remnant and attempt to
probe the magneto-ionic structure and turbulent scale sizes in the ISM and
galactic halo along the line-of-sight.


title: A Lagrangian approach to the Barrett-Crane spin foam model

abstract:
  We provide the Barrett-Crane spin foam model for quantum gravity with a
discrete action principle, consisting in the usual BF term with discretized
simplicity constraints which in the continuum turn topological BF theory into
gravity. The setting is the same as usually considered in the literature:
space-time is cut into 4-simplices, the connection describes how to glue these
4-simplices together and the action is a sum of terms depending on the
holonomies around each triangle. We impose the discretized simplicity
constraints on disjoint tetrahedra and we show how the Lagrange multipliers for
the simplicity constraints distort the parallel transport and the correlations
between neighbouring 4-simplices. We then construct the discretized BF action
using a non-commutative product between $\SU(2)$ plane waves. We show how this
naturally leads to the Barrett-Crane model. This clears up the geometrical
meaning of the model. We discuss the natural generalization of this action
principle and the spin foam models it leads to. We show how the recently
introduced spinfoam fusion coefficients emerge with a non-trivial measure. In
particular, we recover the Engle-Pereira-Rovelli spinfoam model by weakening
the discretized simplicity constraints. Finally, we identify the two sectors of
Plebanski's theory and we give the analog of the Barrett-Crane model in the
non-geometric sector.


title:
Proposal for Direct, Local Measurement of Entanglement for Pure
  Bipartite Systems of Arbitrary Dimension

abstract:
  Based on the complementarity relation between entanglement of a composite
system and the purity of a subsystem, we propose a simple method to measure the
amount of entanglement. The method can be applied to a bipartite system in a
pure state of any arbitrary dimension. It requires only single qudit rotations
and straightforward probability measurements performed on one of the
subsystems, and can thus be easily implemented experimentally using linear
optical devices.


title:
Construction of coarse-grained order-parameters in non-equilibrium
  systems

abstract:
  We develop a renormalization group (RG) procedure that includes important
system-specific features. The key ingredient is to systematize the coarse
graining procedure that generates the RG flow. The coarse graining technology
comes from control and operator theoretic model reduction. The resulting
"generalized" RG is a consistent generalization of the Wilsonian RG. We derive
the form of the projection operator from the dynamics of a nonlinear wave
equation and renormalize the distribution of initial conditions. The
probability density of the initial conditions is chosen to be the Boltzmann
weight for a standard $\phi^4$-theory. In our calculation, we find that in
contrast to conventional implementations of the RG, na\"ive power counting
breaks down. The RG-equations that we derive are different from those derived
from the conventional RG.


title:
Modulation of Electrical Conduction Through Individual Molecules on
  Silicon by the Electrostatic Fields of Nearby Polar Molecules: Theory and
  Experiment

abstract:
  We report on the synthesis, scanning tunneling microscopy (STM) and
theoretical modeling of the electrostatic and transport properties of
one-dimensional organic heterostructures consisting of contiguous lines of CF3-
and OCH3-substituted styrene molecules on silicon. The electrostatic fields
emanating from these polar molecules are found, under appropriate conditions,
to strongly influence electrical conduction through nearby molecules and the
underlying substrate. For suitable alignment of the OCH3 groups of the
OCH3-styrene molecules in the molecular chain, their combined electric fields
are shown by ab initio density functional calculations to give rise to
potential profiles along the OCH3-styrene chain that result in strongly
enhanced conduction through OCH3-styrene molecules near the heterojunction for
moderately low negative substrate bias, as is observed experimentally. Under
similar bias conditions, dipoles associated with the CF3 groups are found in
both experiment and in theory to depress transport in the underlying silicon.
Under positive substrate bias, simulations suggest that the differing
structural and electrostatic properties of the CF3-styrene molecules may lead
to a more sharply localized conduction enhancement near the heterojunction at
low temperatures. Thus choice of substituents, their attachment site on the
host styrene molecules on silicon and the orientations of the molecular dipole
and higher multipole moments provide a means of differentially tuning transport
on the molecular scale.


title: String coupling and interactions in type IIB matrix model

abstract:
  We investigate the interactions of closed strings in IIB matrix model. The
basic interaction of the closed superstring is realized by the recombination of
two intersecting strings. Such interaction is investigated in IIB matrix model
via two dimensional noncommutative gauge theory in the IR limit. By estimating
the probability of the recombination, we identify the string coupling g_s in
IIB matrix model. We confirm that our identification is consistent with matrix
string theory.


title:
The Statistics of Radio Astronomical Polarimetry: Bright Sources and
  High Time Resolution

abstract:
  A four-dimensional statistical description of electromagnetic radiation is
developed and applied to the analysis of radio pulsar polarization. The new
formalism provides an elementary statistical explanation of the modal
broadening phenomenon in single pulse observations. It is also used to argue
that the degree of polarization of giant pulses has been poorly defined in past
studies. Single and giant pulse polarimetry typically involves sources with
large flux densities and observations with high time resolution, factors that
necessitate consideration of source-intrinsic noise and small-number
statistics. Self noise is shown to fully explain the excess polarization
dispersion previously noted in single pulse observations of bright pulsars,
obviating the need for additional randomly polarized radiation. Rather, these
observations are more simply interpreted as an incoherent sum of covariant,
orthogonal, partially polarized modes. Based on this premise, the
four-dimensional covariance matrix of the Stokes parameters may be used to
derive mode-separated pulse profiles without any assumptions about the
intrinsic degrees of mode polarization. Finally, utilizing the small-number
statistics of the Stokes parameters, it is established that the degree of
polarization of an unresolved pulse is fundamentally undefined; therefore,
previous claims of highly polarized giant pulses are unsubstantiated.
Unpublished supplementary material is appended after the bibliography.


title:
Einstein-Rosen waves and the self-similarity hypothesis in cylindrical
  symmetry

abstract:
  The self-similarity hypothesis claims that in classical general relativity,
spherically symmetric solutions may naturally evolve to a self-similar form in
certain circumstances. In this context, the validity of the corresponding
hypothesis in nonspherical geometry is very interesting as there may exist
gravitational waves. We investigate self-similar vacuum solutions to the
Einstein equation in the so-called whole-cylinder symmetry. We find that those
solutions are reduced to part of the Minkowski spacetime with a regular or
conically singular axis and with trivial or nontrivial topology if the
homothetic vector is orthogonal to the cylinders of symmetry. These solutions
are analogous to the Milne universe, but only in the direction parallel to the
axis. Using these solutions, we discuss the nonuniqueness (and nonvanishing
nature) of C energy and the existence of a cylindrical trapping horizon in
Minkowski spacetime. Then, as we generalize the analysis, we find a
two-parameter family of self-similar vacuum solutions, where the homothetic
vector is not orthogonal to the cylinders in general. The family includes the
Minkowski, the Kasner and the cylindrical Milne solutions. The obtained
solutions describe the interior to the exploding (imploding) shell of
gravitational waves or the collapse (explosion) of gravitational waves
involving singularities from nonsingular initial data in general. Since recent
numerical simulations strongly suggest that one of these solutions may describe
the asymptotic behavior of gravitational waves from the collapse of a dust
cylinder, this means that the self-similarity hypothesis is naturally
generalized to cylindrical symmetry.


title:
On the Cauchy problem for focusing and defocusing Gross-Pitaevskii
  hierarchies

abstract:
  We consider the dynamical Gross-Pitaevskii (GP) hierarchy on $\R^d$,
$d\geq1$, for cubic, quintic, focusing and defocusing interactions. For both
the focusing and defocusing case, and any $d\geq1$, we prove local existence
and uniqueness of solutions in certain Sobolev type spaces $\cH_\xi^\alpha$ of
sequences of marginal density matrices. The regularity is accounted for by
$\alpha>\frac12& if $d=1$, $\alpha>\frac d2-\frac{1}{2(p-1)} $ if $d\geq2$ and
$(d,p)\neq(3,2)$, and $\alpha\geq1$ if $(d,p)=(3,2)$, where $p=2$ for the
cubic, and $p=4$ for the quintic GP hierarchy; the parameter $\xi>0$ is
arbitrary and determines the energy scale of the problem. This result includes
the proof of an a priori spacetime bound conjectured by Klainerman and Machedon
for the cubic GP hierarchy in $d=3$. In the defocusing case, we prove the
existence and uniqueness of solutions globally in time for the cubic GP
hierarchy for $1\leq d\leq3$, and of the quintic GP hierarchy for $1\leq d\leq
2$, in an appropriate space of Sobolev type, and under the assumption of an a
priori energy bound. For the focusing GP hierarchies, we prove lower bounds on
the blowup rate. Also pseudoconformal invariance is established in the cases
corresponding to $L^2$ criticality, both in the focusing and defocusing
context. All of these results hold without the assumption of factorized initial
conditions.


title:
Different representations for the action principle in 4D N = 2
  supergravity

abstract:
  Within the superspace formulation for four-dimensional N = 2 matter-coupled
supergravity developed in arXiv:0805.4683, we elaborate two approaches to
reduce the superfield action to components. One of them is based on the
principle of projective invariance which is a purely N = 2 concept having no
analogue in simple supergravity. In this approach, the component reduction of
the action is performed without imposing any Wess-Zumino gauge condition, that
is by keeping intact all the gauge symmetries of the superfield action,
including the super-Weyl invariance. As a simple application, the c-map is
derived for the first time from superfield supergravity. Our second approach to
component reduction is based on the method of normal coordinates around a
submanifold in a curved superspace, which we develop in detail. We derive
differential equations which are obeyed by the vielbein and the connection in
normal coordinates, and which can be used to reconstruct these objects, in
principle in closed form. A separate equation is found for the
super-determinant of the vielbein, which allows one to reconstruct it without a
detailed knowledge of the vielbein. This approach is applicable to any
supergravity theory in any number of space-time dimensions. As a simple
application of this construction, we reduce an integral over the curved N = 2
superspace to that over the chiral subspace of the full superspace. We also
give a new representation for the curved projective-superspace action principle
as a chiral integral.


title: Linearly Parameterized Bandits

abstract:
  We consider bandit problems involving a large (possibly infinite) collection
of arms, in which the expected reward of each arm is a linear function of an
$r$-dimensional random vector $\mathbf{Z} \in \mathbb{R}^r$, where $r \geq 2$.
The objective is to minimize the cumulative regret and Bayes risk. When the set
of arms corresponds to the unit sphere, we prove that the regret and Bayes risk
is of order $\Theta(r \sqrt{T})$, by establishing a lower bound for an
arbitrary policy, and showing that a matching upper bound is obtained through a
policy that alternates between exploration and exploitation phases. The
phase-based policy is also shown to be effective if the set of arms satisfies a
strong convexity condition. For the case of a general set of arms, we describe
a near-optimal policy whose regret and Bayes risk admit upper bounds of the
form $O(r \sqrt{T} \log^{3/2} T)$.


title: Three types of statistics and the entropy bounds

abstract:
  We investigated the entropy bounds of the three types of statistics:
para-Bose, para-Fermi and infinite statistics. We showed that the entropy
bounds of the conventional Bose, Fermi statistics and their generalizations to
parastatistics obey the $A^{3/4}$ law, while the entropy bound of infinite
statistics obeys the area law. This suggests a close relationship between
infinite statistics and quantum gravity.


title:
Resonant flavor conversion of supernova neutrinos and neutrino
  parameters

abstract:
  The unknown neutrino parameters may leave detectable signatures in the
supernova (SN) neutrino flux. However, even the contribution from the MSW
flavor transition alone could cause ambiguity in the interpretation to the
neutrino signals because of the uncertain local density profile of the SN
matter and the model-dependent SN neutrino spectral parameters. A specific
parametrization to the unknown local density profile is proposed in this work,
and the contribution from the standard MSW effect is investigated through a
multi-detector analysis of the SN neutrinos. In establishing the
model-independent scheme, results based on the existing spectral models are
included. The limitation of the analysis is also discussed.


title:
Equilibrium properties of a grafted polyelectrolyte with explicit
  counterions

abstract:
  We study the equilibrium conformations of a grafted polyelectrolyte (PE) in
the presence of explicit counterions (CI) using Monte Carlo simulations. The
interplay between attractive Lennard-Jones interactions (parametrized by
epsilon), and electrostatics (parametrized by A = q^2l_B/a, where q =counterion
valency, l_B = Bjerrum length and a = monomer diameter), results in a variety
of conformations, characterized as extended (E), pearls with m beads (P_m),
sausage (S) and globular (G). For large epsilon, we observe a transition from G
-> P_2 -> P_3 -> . . . -> S -> G with increasing A, i.e., a change from poor to
good, to reentrant poor solvent, whereas, at lower epsilon, the sequence of
transitions is, E -> S -> G. The conformation changes are directly related to
the nature of binding of CI onto the PE. The transition between S -> G is
continuous and associated with critical fluctuations in the shape driven by
fluctuations in the fraction of condensed CI.


title:
A new approach to bulk viscosity in strange quark matter at high
  densities

abstract:
  A new method is proposed to compute the bulk viscosity in strange quark
matter at high densities. Using the method it is straightforward to prove that
the bulk viscosity is positive definite, which is not so easy to accomplish in
other approaches especially for multi-component fluids like strange quark
matter with light up and down quarks and massive strange quarks.


title: Boson star and dark matter

abstract:
  Bound states of complex scalar fields (boson stars) have long been proposed
as possible candidates for the dark matter in the universe. Considerable work
has already been done to study various aspects of boson stars. In the present
work, assuming a particular anisotropic matter distribution, we solve the
Einstein-Klein-Gordon equations with a cosmological constant to obtain bosonic
configurations by treating the problem geometrically. The results are then
applied to problems covering a wide range of masses and radii of the boson
stars and the relevant self interaction parameters are calculated. We compare
our results with earlier treatments to show the applicability of the
geometrical approach.


title: Fixed points of compositions of earthquakes

abstract:
  Let S be a closed surface of genus at least 2, and consider two measured
geodesic laminations that fill S. Right earthquakes along these laminations are
diffeomorphisms of the Teichm\"uller space of S. We prove that the composition
of these earthquakes has a fixed point in the Teichm\"uller space. Another way
to state this result is that it is possible to prescribe any two measured
laminations that fill a surface as the upper and lower measured bending
laminations of the convex core of a globally hyperbolic AdS manifold. The proof
uses some estimates from the geometry of those AdS manifolds.


title: Iterated destabilizing modifications for vector bundles with connection

abstract:
  Given a vector bundle with integrable connection $(V,\nabla)$ on a curve, if
$V$ is not itself semistable as a vector bundle then we can iterate a
construction involving modification by the destabilizing subobject to obtain a
Hodge-like filtration $F^p$ which satisfies Griffiths transversality. The
associated graded Higgs bundle is the limit of $(V,t\nabla)$ under the de Rham
to Dolbeault degeneration. We get a stratification of the moduli space of
connections, with as minimal stratum the space of opers. The strata have
fibrations whose fibers are Lagrangian subspaces of the moduli space.


title:
A lattice model for the second $\mathbb{Z}_{3}$ parafermionic field
  theory

abstract:
  The second $\mathbb{Z}_{3}$ parafermionic conformal theories are associated
with the coset construction $\frac{SU(2)_{k}\times SU(2)_{4}}{SU(2)_{k+4}} $.
Solid-on-solid integrable lattice models obtained by fusion of the model based
on level-1 representation of the affine algebra $B_1^{(1)}$ have a critical
point described by these conformal theories. Explicit values for the Boltzmann
weights are derived for these models, and it is shown that the Boltzmann
weights can be made positive for a particular value of the spectral parameter,
opening a way to eventual numerical simulations of these conformal field
theories. Away from criticality, these lattice models describe an integrable,
massive perturbation of the parafermionic conformal theory by the relevant
field $\Psi_{-2/3}^{\dagger}D_{1,3} $.


title:
Free particle on noncommutative plane -- a coherent state path integral
  approach

abstract:
  We formulate the coherent state path integral on a two dimensional
noncommutative plane using the fact that noncommuative quantum mechanics can be
viewed as a quantum system on the Hilbert space of Hilbert-Schmidt operators
acting on noncommutative configuration space. The propagation kernel for the
free particle shows ultra-violet cutoff which agrees with the earlier
investigations made in the literature but the approach differs substantially
from the earlier studies.


title: Coarse dynamics and fixed point property

abstract:
  We investigate the fixed point property of the group actions on a coarse
space and its Higson corona. We deduce the coarse version of Brouwer's fixed
point theorem.


title:
Structural study on Pr0.55(Ca[1-y]Sr[y])0.45MnO3 thin films on
  perovskite (011) substrate

abstract:
  Structural study on the photo-switching system Pr{0.55}(Ca{1-y}Sr
y){0.45}MnO3 thin films on perovskite (011) substrate has been made with
synchrotron radiation diffraction experiment. The insulating phase of y=0.20
sample was found to be an antiferro-orbital ordered phase with large lattice
distortion and the ferromagnetic metallic phase of y=0.40 film show no distinct
lattice distortion from the paramagnetic phase, which are very similar with
(Nd,Pr)0.5Sr0.5MnO3 films. A striking contrast of the orbital ordered phase of
y=0.20 film to (Nd,Pr)0.5Sr0.5MnO3 films was its untwinned structure.


title: Relativistic model of hidden bottom tetraquarks

abstract:
  The relativistic model of the ground state and excited heavy tetraquarks with
hidden bottom is formulated within the diquark-antidiquark picture. The diquark
structure is taken into account by calculating the diquark-gluon vertex in
terms of the diquark wave functions. Predictions for the masses of bottom
counterparts to the charm tetraquark candidates are given.


title:
Automatic Construction of Lightweight Domain Ontologies for Chemical
  Engineering Risk Management

abstract:
  The need for domain ontologies in mission critical applications such as risk
management and hazard identification is becoming more and more pressing. Most
research on ontology learning conducted in the academia remains unrealistic for
real-world applications. One of the main problems is the dependence on
non-incremental, rare knowledge and textual resources, and manually-crafted
patterns and rules. This paper reports work in progress aiming to address such
undesirable dependencies during ontology construction. Initial experiments
using a working prototype of the system revealed promising potentials in
automatically constructing high-quality domain ontologies using real-world
texts.


title:
Superfluidity and Anderson localisation for a weakly interacting Bose
  gas in a quasiperiodic potential

abstract:
  Using exact diagonalisation and Density Matrix Renormalisation group (DMRG)
approach, we analyse the transition to a localised state of a weakly
interacting quasi-1D Bose gas subjected to a quasiperiodic potential. The
analysis is performed by calculating the superfluid fraction, density profile,
momentum distribution and visibility for different periodicities of the second
lattice and in the presence (or not) of a weak repulsive interaction. It is
shown that the transition is sharper towards the maximally incommensurate ratio
between the two lattice periodicities, and shifted to higher values of the
second lattice strength by weak repulsive interactions. We also relate our
results to recent experiments.


title: Nonsensitive nonlinear homotopy approach

abstract:
  Generally, natural scientific problems are so complicated that one has to
establish some effective perturbation or nonperturbation theories with respect
to some associated ideal models. In this Letter, a new theory that combines
perturbation and nonperturbation is constructed. An artificial nonlinear
homotopy parameter plays the role of a perturbation parameter, while other
artificial nonlinear parameters, of which the original problems are
independent, introduced in the nonlinear homotopy models are nonperturbatively
determined by means of a principle minimal sensitivity. The method is
demonstrated through several quantum anharmonic oscillators and a non-hermitian
parity-time symmetric Hamiltonian system. In fact, the framework of the theory
is rather general that can be applied to a broad range of natural phenomena.
Possible applications to condensed matter physics, matter wave systems, and
nonlinear optics are briefly discussed.


title:
Resonant optical electron transfer in one-dimensional multiwell
  structures

abstract:
  We consider coherent single-electron dynamics in the one-dimensional
nanostructure under resonant electromagnetic pulse. The structure is composed
of two deep quantum wells positioned at the edges of structure and separated by
a sequence of shallow internal wells. We show that complete electron transfer
between the states localized in the edge wells through one of excited
delocalized states can take place at discrete set of times provided that the
pulse frequency matches one of resonant transition frequencies. The transfer
time varies from several tens to several hundreds of picoseconds and depends on
the structure and pulse parameters. The results obtained in this paper can be
applied to the developments of the quantum networks used in quantum
communications and/or quantum information processing.


title:
On the Spectral Analysis of Quantum Electrodynamics with Spatial
  Cutoffs. I

abstract:
  In this paper, we consider the spectrum of a model in quantum electrodynamics
with a spatial cutoff. It is proven that (1) the Hamiltonian is self-adjoint;
  (2) under the infrared regularity condition, the Hamiltonian has a unique
ground state for sufficiently small values of coupling constants. The spectral
scattering theory is studied as well and it is shown that asymptotic fields
exist and the spectral gap is closed.


title: A rank-based selection with cardinal payoffs and a cost of choice

abstract:
  A version of the secretary problem is considered. The ranks of items, whose
values are independent, identically distributed random variables
$X_1,X_2,...,X_n$ from a uniform distribution on $[0; 1]$, are observed
sequentially by the grader. He has to select exactly one item, when it appears,
and receives a payoff which is a function of the unobserved realization of
random variable assigned to the item diminished by some cost. The methods of
analysis are based on the existence of an embedded Markov chain and use the
technique of backward induction. The result is a generalization of the
selection model considered by Bearden(2006). The asymptotic behaviour of the
solution is also investigated.


title:
Charge qubit entanglement via conditional single-electron transfer in an
  array of quantum dots

abstract:
  We propose a novel scheme to generate entanglement among quantum-dot-based
charge qubits via sequential electron transfer in an auxiliary quantum dot
structure whose transport properties are conditioned by qubit states. The
transfer protocol requires the utilization of resonant optical pulses combined
with an appropriate voltage gate pattern. As an example illustrating the
application of this scheme, we examine the nine-qubit Shor code state
preparation together with the error syndrome measurement.


title:
Maximum empirical likelihood estimation of the spectral measure of an
  extreme-value distribution

abstract:
  Consider a random sample from a bivariate distribution function $F$ in the
max-domain of attraction of an extreme-value distribution function $G$. This
$G$ is characterized by two extreme-value indices and a spectral measure, the
latter determining the tail dependence structure of $F$. A major issue in
multivariate extreme-value theory is the estimation of the spectral measure
$\Phi_p$ with respect to the $L_p$ norm. For every $p\in[1,\infty]$, a
nonparametric maximum empirical likelihood estimator is proposed for $\Phi_p$.
The main novelty is that these estimators are guaranteed to satisfy the moment
constraints by which spectral measures are characterized. Asymptotic normality
of the estimators is proved under conditions that allow for tail independence.
Moreover, the conditions are easily verifiable as we demonstrate through a
number of theoretical examples. A simulation study shows a substantially
improved performance of the new estimators. Two case studies illustrate how to
implement the methods in practice.


title:
Quality factor analysis and optimization of digital filtering signal
  reconstruction for liquid ionization calorimeters

abstract:
  The Optimal Filtering (OF) reconstruction of the sampled signals from a
particle detector such as a liquid ionization calorimeter relies on the
knowledge of the normalized pulse shapes. This knowledge is always imprecise,
since there are residual differences between the true ionization pulse shapes
and the predicted ones, whatever the method used to model or fit the
particle--induced signals. The systematic error introduced by the residuals on
the signal amplitude estimate is analyzed, as well as the effect on the quality
factor provided by the OF reconstruction. An analysis method to evaluate the
residuals from a sample of signals is developed and tested with a simulation
tool. The correction obtained is showed to preserve the original amplitude
normalization, while restoring the expected $\chi^2 $--like behavior of the
quality factor.


title: Signatures of currency vertices

abstract:
  Many real-world networks have broad degree distributions. For some systems,
this means that the functional significance of the vertices is also broadly
distributed, in other cases the vertices are equally significant, but in
different ways. One example of the latter case is metabolic networks, where the
high-degree vertices -- the currency metabolites -- supply the molecular groups
to the low-degree metabolites, and the latter are responsible for the
higher-order biological function, of vital importance to the organism. In this
paper, we propose a generalization of currency metabolites to currency
vertices. We investigate the network structural characteristics of such
systems, both in model networks and in some empirical systems. In addition to
metabolic networks, we find that a network of music collaborations and a
network of e-mail exchange could be described by a division of the vertices
into currency vertices and others.


title: Noncommutative Quantum Cosmology

abstract:
  One presents a phase-space noncommutative extension of Quantum Cosmology in
the context of a Kantowski-Sachs (KS) minisuperspace model. We obtain the
Wheeler-DeWitt (WDW) equation for the noncommutative system through the ADM
formalism and a suitable Seiberg-Witten map. The resulting WDW equation
explicitly depends on the phase-space noncommutative parameters, $\theta$ and
$\eta$. Numerical solutions of the noncommutative WDW equation are found and,
interestingly, also bounds on the values of the noncommutative parameters.
Moreover, we conclude that the noncommutativity in the momenta sector leads to
a damped wave function implying that this type of noncommutativity can be
relevant for a selection of possible initial states for the universe.


title: Krull dimension of types in a class of first-order theories

abstract:
  We study a class of first-order theories whose complete quantifier-free types
with one free variable either have a trivial positive part or are isolated by a
positive quantifier-free formula--plus a few other technical requirements. The
theory of vector spaces and the theory fields are examples. We prove the
amalgamation property and the existence of a model-companion. We show that the
model-companion is strongly minimal. We also prove that the length of any
increasing sequence of prime types is bounded, so every formula has finite
Krull dimension.


title: The semiflexible fully-packed loop model and interacting rhombus tilings

abstract:
  Motivated by a recent adsorption experiment [M.O. Blunt et al., Science 322,
1077 (2008)], we study tilings of the plane with three different types of
rhombi. An interaction disfavors pairs of adjacent rhombi of the same type.
This is shown to be a special case of a model of fully-packed loops with
interactions between monomers at distance two along a loop. We solve the latter
model using Coulomb gas techniques and show that its critical exponents vary
continuously with the interaction strenght. At low temperature it undergoes a
Kosterlitz-Thouless transition to an ordered phase, which is predicted from
numerics to occur at a temperature T \sim 110K in the experiments.


title: The Milky Way Spiral Arm Pattern

abstract:
  A complete map of the 3D distribution of molecular (CO) gas was constructed
using a realistic dynamical model of the gas flow in the barred potential of
the Milky Way. The map shows two prominent spiral arms starting at the bar ends
connecting smoothly to the 4-armed spiral pattern observed in the atomic
hydrogen gas in the outer Galaxy. Unlike previous attempts, our new map
uncovers the gas distribution in the bar region of the Galaxy and the far side
of the disk. For the first time, we can follow spiral arms in gas as they pass
behind the galactic centre.


title: Effective shape and phase behaviour of short charged rods

abstract:
  We explicitly calculate the orientation-dependent second virial coefficient
of short charged rods in an electrolytic solvent, assuming the rod-rod
interactions to be a pairwise sum of hard-core and segmental screened-Coulomb
repulsions. From the parallel and isotropically averaged second virial
coefficient, we calculate the effective length and diameter of the rods, for
charges and screening lengths that vary over several orders of magnitude. Using
these effective dimensions, we determine the phase diagram, where we
distinguish a low-charge and strong-screening regime with a liquid crystalline
nematic and smectic phase, and a high-charge and weak-screening regime with a
plastic crystal phase in the phase diagram.


title:
The self-interaction force on an arbitrarily moving point-charge and its
  energy-momentum radiation rate: A mathematically rigorous derivation of the
  Lorentz-Dirac equation of motion

abstract:
  The classical theory of radiating point-charges is revisited: the retarded
potentials, fields, and currents are defined as nonlinear generalized functions
and all calculations are made in a Colombeau algebra. The total rate of
energy-momentum radiated by an arbitrarily moving relativistic point-charge
under the effect of its own field is shown to be rigorously equal to minus the
self-interaction force due to that field. This solves, without changing
anything in Maxwell's theory, numerous long-standing problems going back to
more than a century. As an immediate application an unambiguous derivation of
the Lorentz-Dirac equation of motion is given, and the origin of the problem
with the Schott term is explained: it was due to the fact that the correct
self-energy of a point charge is not the Coulomb self-energy, but an integral
over a delta-squared function which yields a finite contribution to the Schott
term that is either absent or incorrect in the customary formulations.


title:
Three-dimensional Radiative Transfer Modeling of the Polarization of the
  Sun's Continuous Spectrum

abstract:
  Here we formulate and solve the 3D radiative transfer problem of the
polarization of the solar continuous radiation. Our approach takes into account
not only the anisotropy of the continuum radiation, but also the
symmetry-breaking effects caused by the horizontal atmospheric inhomogeneities
produced by the solar surface convection. Interestingly, our radiative transfer
modeling in a well-known 3D hydrodynamical model of the solar photosphere shows
remarkable agreement with the empirical data, significantly better than that
obtained via the use of 1D atmospheric models. Although this result confirms
that the above-mentioned 3D model was indeed a suitable choice for our
Hanle-effect estimation of the substantial amount of "hidden" magnetic energy
that is stored in the quiet solar photosphere, we have found however some small
discrepancies whose origin may be due to uncertainties in the empirical data
and/or in the thermal and density structure of the 3D model. For this reason,
we have paid some attention also to other (more familiar) observables, like the
center-limb variation of the continuum intensity, which we have calculated
taking into account the scattering contribution to the continuum source
function. The overall agreement with the observed center-limb variation turns
out to be impressive, but we find a hint that the model's temperature gradients
in the continuum forming layers could be slightly too steep, perhaps because
all current simulations of solar surface convection and magnetoconvection
compute the radiative flux divergence ignoring the fact that the effective
polarizability is not completely negligible, especially in the downward-moving
intergranular lane plasma.


title: Status of the ALPS Experiment

abstract:
  The ALPS experiment at DESY searches for light particles which are coupling
very weakly to photons. Primary physics goal is the search for axion like
particles in a photon regeneration experiment. Central part of the experimental
setup is a five Tesla strong superconducting HERA dipole magnet. During two
operation periods in the years 2007 and 2008 we have collected first data and
explored the sensitivity of the setup. A Fabry Perot laser cavity is being set
up in order to increase the sensitivity by more than one order of magnitude.


title: Linear independence over tropical semirings and beyond

abstract:
  We investigate different notions of linear independence and of matrix rank
that are relevant for max-plus or tropical semirings. The factor rank and
tropical rank have already received attention, we compare them with the ranks
defined in terms of signed tropical determinants or arising from a notion of
linear independence introduced by Gondran and Minoux. To do this, we revisit
the symmetrization of the max-plus algebra, establishing properties of linear
spaces, linear systems, and matrices over the symmetrized max-plus algebra. In
parallel we develop some general technique to prove combinatorial and
polynomial identities for matrices over semirings that we illustrate by a
number of examples.


title:
Controlling the onset of traveling pulses in excitable media by nonlocal
  spatial coupling and time-delayed feedback

abstract:
  The onset of pulse propagation is studied in a reaction-diffusion (RD) model
with control by augmented transmission capability that is provided either along
nonlocal spatial coupling or by time-delayed feedback. We show that traveling
pulses occur primarily as solutions to the RD equations while augmented
transmission changes excitability. For certain ranges of the parameter
settings, defined as weak susceptibility and moderate control, respectively,
the hybrid model can be mapped to the original RD model. This results in an
effective change of RD parameters controlled by augmented transmission. Outside
moderate control parameter settings new patterns are obtained, for example
step-wise propagation due to delay-induced oscillations. Augmented transmission
constitutes a signaling system complementary to the classical RD mechanism of
pattern formation. Our hybrid model combines the two major signaling systems in
the brain, namely volume transmission and synaptic transmission. Our results
provide insights into the spread and control of pathological pulses in the
brain.


title:
The transverse shift of a high order paraxial vortex-beam induced by a
  homogeneous anisotropic medium

abstract:
  We consider the propagation of a tilted high order paraxial vortex-beam
through a homogeneous anisotropic medium of a uniaxial crystal. We found that
the initially circularly polarized beam bearing the l-order optical vortex
splits into ordinary and extraordinary beams with a complex vortex structure.
After a series of dislocation reactions the vortices gather together at the
axis of the partial beam with the initial circular polarization shaping the
l-order optical vortex. However, only l-1 vortices gather together on the axis
of the partial beam with the orthogonal circular polarization. One optical
vortex is shifted along the direction perpendicular to the inclination plane of
the beam. Such a vortex displacement induces the transverse shift of the
partial beam. In fact, we deal with the beam quadrefringence in a uniaxial,
homogeneous anisotropic medium. The first two beams is a result of the
splitting of the initial tilted beam into the ordinary and extraordinary once.


title:
An Effective Lower Bound for Group Complexity of Finite Semigroups and
  Automata

abstract:
  The question of computing the group complexity of finite semigroups and
automata was first posed in K. Krohn and J. Rhodes, \textit{Complexity of
finite semigroups}, Annals of Mathematics (2) \textbf{88} (1968), 128--160,
motivated by the Prime Decomposition Theorem of K. Krohn and J. Rhodes,
\textit{Algebraic theory of machines, {I}: {P}rime decomposition theorem for
finite semigroups and machines}, Transactions of the American Mathematical
Society \textbf{116} (1965), 450--464. Here we provide an effective lower bound
for group complexity.


title:
Limits on Isocurvature Perturbations from Non-Gaussianity in WMAP
  Temperature Anisotropies

abstract:
  We study the effect of primordial isocurvature perturbations on non-Gaussian
properties of CMB temperature anisotropies. We consider generic forms of the
non-linearity of isocurvature perturbations which can be applied to a wide
range of theoretical models. We derive analytical expressions for the
bispectrum and the Minkowski Functionals for CMB temperature fluctuations to
describe the non-Gaussianity from isocurvature perturbations. We find that the
isocurvature non-Gaussianity in the quadratic isocurvature model, where the
isocurvature perturbation S is written as a quadratic function of the Gaussian
variable sigma, S=sigma^2-<sigma^2>, can give the same signal-to-noise as
f_NL=30 even if we impose the current observational limit on the fraction of
isocurvature perturbations contained in the primordial power spectrum alpha. We
give constraints on isocurvature non-Gaussianity from Minkowski Functionals
using WMAP 5-year data. We do not find a significant signal of the isocurvature
non-Gaussianity. For the quadratic isocurvature model, we obtain a stringent
upper limit on the isocurvature fraction alpha<0.070 (95% CL) for a scale
invariant spectrum which is comparable to the limit obtained from the power
spectrum.


title:
Dipole Oscillations of a Fermi Gas in a Disordered Trap: Damping and
  Localization

abstract:
  We theoretically study the dipole oscillations of an ideal Fermi gas in a
disordered trap. We show that even weak disorder induces strong damping of the
oscillations and we identify a metal-insulator crossover. For very weak
disorder, we show that damping results from a dephasing effect related to weak
random perturbations of the energy spectrum. For increasing disorder, we show
that the Fermi gas crosses over to an insulating regime characterized by
strong-damping due to the proliferation of localized states.


title:
A deconvolution approach to estimation of a common shape in a shifted
  curves model

abstract:
  This paper considers the problem of adaptive estimation of a mean pattern in
a randomly shifted curve model. We show that this problem can be transformed
into a linear inverse problem, where the density of the random shifts plays the
role of a convolution operator. An adaptive estimator of the mean pattern,
based on wavelet thresholding is proposed. We study its consistency for the
quadratic risk as the number of observed curves tends to infinity, and this
estimator is shown to achieve a near-minimax rate of convergence over a large
class of Besov balls. This rate depends both on the smoothness of the common
shape of the curves and on the decay of the Fourier coefficients of the density
of the random shifts. Hence, this paper makes a connection between mean pattern
estimation and the statistical analysis of linear inverse problems, which is a
new point of view on curve registration and image warping problems. We also
provide a new method to estimate the unknown random shifts between curves. Some
numerical experiments are given to illustrate the performances of our approach
and to compare them with another algorithm existing in the literature.


title: Grand Unification in the Heterotic Brane World

abstract:
  The compactification of the heterotic string on six-dimensional orbifolds is
reviewed. Some important technical aspects of their construction are clarified
and new parameters, called generalized discrete torsion, are introduced and
related to the torsionless construction. Furthermore, a systematic search for
MSSM-like models is performed in the context of Z6-II orbifolds, addressing
questions like the identification of a supersymmetric vacuum with a naturally
small mu-term and proton decay. Finally, the blow-up of Z3 singularities is
discussed in the local and in the global case - also in the presence of Wilson
lines. This procedure is exemplified with the resolution of a Z3 MSSM
candidate.


title: Magnetic relaxation in pulse-magnetized high-temperature superconductors

abstract:
  A magnetic field relaxation at the center of a pulse-magnetized single-domain
Y-Ba-Cu-O superconductor at 78K has been studied. In case of a weak
magnetization, the magnetic flux density increases logarithmically and
normalized relaxation rate defined as S=-d(lnB)/d(lnt) is negative (S=-0.037).
When an external magnetic field magnitude increases, the relaxation rate first
decreases in absolute value, then changes sign (becomes positive, S>0) and
after reaching some maximum finally reduces to a very small value.
Non-monotonous dependence of S vs Ha is explained by a non-homogeneous local
temperature distribution during a pulse magnetization.


title: Epidemic modelling: aspects where stochasticity matters

abstract:
  Epidemic models are always simplifications of real world epidemics. Which
real world features to include, and which simplifications to make, depend both
on the disease of interest and on the purpose of the modelling. In the present
paper we discuss some such purposes for which a \emph{stochastic} model is
preferable to a \emph{deterministic} counterpart. The two main examples
illustrate the importance of allowing the infectious and latent periods to be
random when focus lies on the \emph{probability} of a large epidemic outbreak
and/or on the initial \emph{speed}, or growth rate, of the epidemic. A
consequence of the latter is that estimation of the basic reproduction number
$R_0$ is sensitive to assumptions about the distributions of the infectious and
latent periods when using the data from the early stages of an outbreak, which
we illustrate with data from the SARS outbreak. Some further examples are also
discussed as are some practical consequences related to these stochastic
aspects.


title: Focused Fields of given Power with Maximum Electric Field Components

abstract:
  Closed formulas are derived for the field in the focal region of a
diffraction limited lens, such that the electric field component in a given
direction at the focal point is larger than that of all other focused fields
with the same power in the entrance pupil of the lens. Furthermore, closed
formulas are derived for the corresponding optimum field distribution in the
lens pupil. Focused fields with maximum longitudinal or maximum transverse are
considered in detail. The latter field is similar, but not identical, to the
focused linearly polarized plane wave.


title: Coordinate Dependence of Chern-Simons Theory on Noncommutative AdS3

abstract:
  We investigate the coordinate dependence of noncommutative theory by studying
the solutions of noncommutative $U(1,1)\times U(1,1)$ Chern-Simons theory on
$AdS_3$ in the polar and rectangular coordinates. We assume that only the space
coordinates are noncommuting. The two coordinate systems are equivalent only up
to first order in the noncommutativity parameter $\theta$. We investigate the
effect of this non-exact equivalence between the two coordinate systems in two
cases, a conical solution and a BTZ black hole solution, using the
Seiberg-Witten map. In each case, the noncommutative solutions in the two
coordinate systems obtained from the corresponding same commutative solution
turn out to be different even in the first order in $\theta$.


title:
An irreducible approach to second-order reducible second-class
  constraints

abstract:
  An irreducible canonical approach to second-order reducible second-class
constraints is given. The procedure is exemplified on gauge-fixed three-forms.


title: New Measurement of the 2S Hyperfine Interval in Atomic Hydrogen

abstract:
  An optical measurement of the 2S hyperfine interval in atomic hydrogen using
two-photon spectroscopy of the 1S-2S transition gives a value of 177 556
834.3(6.7) Hz. The uncertainty is
  2.4 times smaller than achieved by our group in 2003 and more than 4 times
smaller than for any independent radio-frequency measurement. The specific
combination of the 2S and 1S hyperfine intervals predicted by QED theory
$D_{21}=8 f_{\rm HFS}({2S}) - f_{\rm HFS}({1S})=48 953(3)$ Hz is in good
agreement with the value of 48 923(54) Hz obtained from this experiment.


title:
Hamiltonian tomography in an access-limited setting without state
  initialization

abstract:
  We propose a scheme for the determination of the coupling parameters in a
chain of interacting spins. This requires only time-resolved measurements over
a single particle, simple data post-processing and no state initialization or
prior knowledge of the state of the chain. The protocol fits well into the
context of quantum-dynamics characterization and is efficient even when the
spin-chain is affected by general dissipative and dephasing channels. We
illustrate the performance of the scheme by analyzing explicit examples and
discuss possible extensions.


title: White dwarf axions, PAMELA data, and flipped-SU(5)

abstract:
  Recently, there are two hints arising from physics beyond the standard model.
One is a possible energy loss mechanism due to emission of very weakly
interacting light particles from white dwarf stars, with a coupling strength ~
0.7x10^{-13}, and another is the high energy positrons observed by the PAMELA
satellite experiment. We construct a supersymmetric flipped-SU(5) model,
SU(5)xU(1)_X with appropriate additional symmetries,
[U(1)_H]_{gauge}x[U(1)_RxU(1)_\Gamma]_{global}xZ_2, such that these are
explained by a very light electrophilic axion of mass 0.5 meV from the
spontaneously broken U(1)_\Gamma and two component cold dark matters from Z_2
parity. We show that in the flipped-SU(5) there exists a basic mechanism for
allowing excess positrons through the charged SU(2) singlet leptons, but not
allowing anti-proton excess due to the absence of the SU(2) singlet quarks. We
show the discovery potential of the charged SU(2) singlet E at the LHC
experiments by observing the electron and positron spectrum. With these
symmetries, we also comment on the mass hierarchy between the top and bottom
quarks.


title: Spectral Discontinuities in Constrained Dynamical Models

abstract:
  As examples of models having interesting constraint structures, we derive a
quantum mechanical model from the spatial freezing of a well known relativistic
field theory - the chiral Schwinger model. We apply the Hamiltonian constraint
analysis of Dirac [1] and find that the nature of constraints depends
critically on a $c$-number parameter present in the model. Thus a change in the
parameter alters the number of dynamical modes in an abrupt and
non-perturbative way.
  We have obtained new {\it{real}} energy levels for the quantum mechanical
model as we explore {\it{complex}} domains in the parameter space. These were
forbidden in the parent chiral Schwinger field theory where the analogue
Jackiw-Rajaraman parameter is restricted to be real. We explicitly show
existence of modes that satisfy higher derivative Pais-Uhlenbeck form of
dynamics [3].
  We also show that the Cranking Model [7], well known in Nuclear Physics, can
be interpreted as a spatially frozen version of another well studied
relativistic field theory in 2+1-dimension- the Maxwell-Chern-Simons-Proca
Model [8].


title: Particle decays and stability on the de Sitter universe

abstract:
  We study particle decay in de Sitter space-time as given by first order
perturbation theory in a Lagrangian interacting quantum field theory. We study
in detail the adiabatic limit of the perturbative amplitude and compute the
"phase space" coefficient exactly in the case of two equal particles produced
in the disintegration. We show that for fields with masses above a critical
mass $m_c$ there is no such thing as particle stability, so that decays
forbidden in flat space-time do occur here. The lifetime of such a particle
also turns out to be independent of its velocity when that lifetime is
comparable with de Sitter radius. Particles with mass lower than critical have
a completely different behavior: the masses of their decay products must obey
quantification rules, and their lifetime is zero.


title:
Anomalous non-linear response of glassy liquids: general arguments and a
  Mode-Coupling approach

abstract:
  We study theoretically the non-linear response properties of glass formers.
We establish several general results which, together with the assumption of
Time-Temperature Superposition, lead to a relation between the non-linear
response and the derivative of the linear response with respect to temperature.
Using results from Mode-Coupling Theory (MCT) and scaling arguments valid close
to the glass transition, we obtain the frequency and temperature dependence of
the non-linear response in the $\alpha$ and $\beta$-regimes. Our results
demonstrate that supercooled liquids are characterized by responses to external
perturbations that become increasingly non-linear as the glass transition is
approached. These results are extended to the case of inhomogeneous perturbing
fields.


title:
Parametric resonances in electrostatically interacting carbon nanotube
  arrays

abstract:
  We study, numerically and analytically, a model of a one-dimensional array of
carbon nanotube resonators in a two-terminal configuration. The system is
brought into resonance upon application of an AC-signal superimposed on a
DC-bias voltage. When the tubes in the array are close to each other,
electrostatic interactions between tubes become important for the array
dynamics. We show that both transverse and longitudinal parametric resonances
can be excited in addition to primary resonances. The intertube electrostatic
interactions couple modes in orthogonal directions and affect the mode
stability.


title: Canonical connection on quasi-Kaehler manifolds with Norden metric

abstract:
  We study the geometry of the canonical connection on a quasi-Kaehler manifold
with Norden metric. We consider the cases when the canonical connection has
Kaehler curvature tensor and parallel torsion, and derive conditions for an
isotropic-Kaehler manifold. We give the relation between the canonical
connection, the B-connection, and the connection with totally skew-symmetric
torsion on quasi-Kaehler manifolds with Norden metric.


title:
The functional integral with unconditional Wiener measure for anharmonic
  oscillator

abstract:
  In this article we propose the calculation of the unconditional Wiener
measure functional integral with a term of the fourth order in the exponent by
an alternative method as in the conventional perturbative approach. In contrast
to the conventional perturbation theory, we expand into power series the term
linear in the integration variable in the exponent. In such a case we can
profit from the representation of the integral in question by the parabolic
cylinder functions. We show that in such a case the series expansions are
uniformly convergent and we find recurrence relations for the Wiener functional
integral in the $N$ - dimensional approximation. In continuum limit we find
that the generalized Gelfand - Yaglom differential equation with solution
yields the desired functional integral (similarly as the standard Gelfand -
Yaglom differential equation yields the functional integral for linear harmonic
oscillator).


title:
Diversity of rationality affects cooperation in spatial prisoner's
  dilemma game

abstract:
  In real world, individual rationality varies for the sake of the diversity of
people's individuality. In order to investigate how diversity of agent's
rationality affects the evolution of cooperation, we introduce the individual
rationality proportional to the $\beta$th power of the each agent's degree.
Simulation results on heterogeneous scale-free network show that the dynamic
process is greatly affected by the diversity of rationality. Both promotion and
inhibition of cooperative behavior can be observed at different region of
parameter $\beta$. We present explanation to these results by quantitative and
qualitative analysis. The nodes with middle degree value are found to play a
critical role in the evolutionary processes. The inspiration from our work may
provide us a deeper comprehension towards some social phenomenon.


title: Quintic surfaces with maximum and other Picard numbers

abstract:
  This paper investigates the Picard numbers of quintic surfaces. We give the
first example of a complex quintic surface in IP^3 with maximum Picard number
45. We also investigate its arithmetic and determine the zeta function. Similar
techniques are applied to produce quintic surfaces with several other Picard
numbers that have not been achieved before.


title: Pion and muon yields from a 10 GeV proton beam on various targets

abstract:
  We present results from MARS Monte Carlo simulations of the accepted pion and
muon yields when a 10 GeV parabolic proton beam interacts with a solid or
powdered (50% density) tungsten target for a Neutrino Factory. We compare these
yields with the mercury jet target configuration and find that they all give
similar rates of pion production. Also provided are estimates of the amount of
pion re-absorption inside the target.


title: Polemic Notes On IR Perturbative Quantum Gravity

abstract:
  Quantum gravity is an important and to great extent unsolved problem. There
are many different approaches to the quantization of the metric field, both
perturbative and non-perturbative. The current situation in the perturbative
quantum gravity is characterized by a number of different models, some of them
well elaborated but no one perfect nor mathematically neither
phenomenologically, mainly because there are no theoretically derived
observables which can be experimentally measured. A very interesting one is an
effective approach which separates the low-energy quantum effects from the UV
sector. In this way one can calculate quantities which are potentially relevant
for establishing certain universal features of quantum gravity. In this
presentation we give a polemic consideration of the effective approach to the
infrared quantum gravity. We question the validity of the recent results in
this area and also discuss how one can check the alleged universality of the
effective approach.


title:
Relativistically invariant analysis of $\Delta $--isobar production in
  deuteron electrodisintegration: $e^-+d\to e^-+\Delta +N:$ general analysis of
  polarization effects

abstract:
  The differential cross section and the polarization observables for $\Delta
$--isobar production in the deuteron electrodisintegration process, $e^-+d\to
e^-+\Delta +N$, are calculated in a general formalism based on structure
functions. The obtained expressions have a general nature, hold for
one--photon--exchange, assuming P--invariance of the electromagnetic
interaction and the conservation of the hadron electromagnetic current. The
dependence of the differential cross section of the $e^-+d\to e^- +\Delta +N$
reaction on the vector and tensor polarizations of the deuteron target with
unpolarized and longitudinally polarized electrons is considered. The general
dependence of the asymmetries on two of five kinematic variables, the azimuthal
angle $\phi$ and $\epsilon$ (linear polarization of the virtual photon) is
calculated. A similar analysis is performed for the polarization of the nucleon
produced in $\gamma ^*d \to \Delta N$ reaction provided the electron beam is
unpolarized or longitudinally polarized. Polarization effects, which are due to
the strong $\Delta N-$ interaction in the final state are calculated. The
photoproduction of the $\Delta $--isobar on the deuteron target has been
considered in detail, as a particular case. The differential cross section and
various polarization observables have been derived in terms of the reaction
amplitudes. The polarization observables due to the linear and circular
polarizations of the photon, when the deuteron target is arbitrarily polarized
have been derived in terms of the reaction amplitudes. The polarization of the
final nucleon is also considered.


title:
Testing metabolic scaling theory using intraspecific allometries in
  Antarctic microarthropods

abstract:
  Quantitative scaling relationships among body mass, temperature and metabolic
rate of organisms are still controversial, while resolution may be further
complicated through the use of different and possibly inappropriate approaches
to statistical analysis. We propose the application of a modelling strategy
based on Akaike's information criteria and non-linear model fitting (nlm).
Accordingly, we collated and modelled available data at intraspecific level on
the individual standard metabolic rate of Antarctic microarthropods as a
function of body mass (M), temperature (T), species identity (S) and high rank
taxa to which species belong (G) and tested predictions from Metabolic Scaling
Theory. We also performed allometric analysis based on logarithmic
transformations (lm). Conclusions from lm and nlm approaches were different.
Best-supported models from lm incorporated T, M and S. The estimates of the
allometric scaling exponent b linking body mass and metabolic rate indicated no
interspecific difference and resulted in a value of 0.696 +/- 0.105 (mean +/-
95% CI). In contrast, the four best-supported nlm models suggested that both
the scaling exponent and activation energy significantly vary across the high
rank taxa to which species belong, with mean values of b ranging from about 0.6
to 0.8. We therefore reached two conclusions: 1) published analyses of
arthropod metabolism based on logarithmic data may be biased by data
transformation; 2) non-linear models applied to Antarctic microarthropod
metabolic rate suggest that intraspecific scaling of standard metabolic rate in
Antarctic microarthropods is highly variable and can be characterised by
scaling exponents that greatly vary within taxa, which may have biased previous
interspecific comparisons that neglected intraspecific variability.