title: 3D Face Recognition with Sparse Spherical Representations

abstract:
  This paper addresses the problem of 3D face recognition using simultaneous
sparse approximations on the sphere. The 3D face point clouds are first aligned
with a novel and fully automated registration process. They are then
represented as signals on the 2D sphere in order to preserve depth and geometry
information. Next, we implement a dimensionality reduction process with
simultaneous sparse approximations and subspace projection. It permits to
represent each 3D face by only a few spherical functions that are able to
capture the salient facial characteristics, and hence to preserve the
discriminant facial information. We eventually perform recognition by effective
matching in the reduced space, where Linear Discriminant Analysis can be
further activated for improved recognition performance. The 3D face recognition
algorithm is evaluated on the FRGC v.1.0 data set, where it is shown to
outperform classical state-of-the-art solutions that work with depth images.


title:
Coactions on Hochschild Homology of Hopf-Galois Extensions and Their
  Coinvariants

abstract:
  Let A be an H-Galois extension of B. If M is a Hopf bimodule then HH.(A,M),
the Hochschild homology of A with coefficients in M, is a right comodule over
the coalgebra C:=H/[H,H]. Given an injective left C-comodule V, we denote the
cotensor product of M and V by N. Our aim is to investigate the relationship
between the cotensor product of HH.(A,M) and V, on the one hand, and HH.(B,N)
on the other hand. The roots of this problem can be found in Lorenz's work on
the descent of Hochschild homology of centrally Galois extensions, where
HH.(A)^G, the subspace of invariant cycles with respect to the action of the
Galois group, and HH.(B) are shown to be isomorphic.


title:
Integrable hydrodynamics of Calogero-Sutherland model: Bidirectional
  Benjamin-Ono equation

abstract:
  We develop a hydrodynamic description of the classical Calogero-Sutherland
liquid: a Calogero-Sutherland model with an infinite number of particles and a
non-vanishing density of particles. The hydrodynamic equations, being written
for the density and velocity fields of the liquid, are shown to be a
bidirectional analogue of Benjamin-Ono equation. The latter is known to
describe internal waves of deep stratified fluids. We show that the
bidirectional Benjamin-Ono equation appears as a real reduction of the modified
KP hierarchy. We derive the Chiral Non-linear Equation which appears as a
chiral reduction of the bidirectional equation. The conventional Benjamin-Ono
equation is a degeneration of the Chiral Non-Linear Equation at large density.
We construct multi-phase solutions of the bidirectional Benjamin-Ono equations
and of the Chiral Non-Linear equations.

categories: cond-mat.str-el cond-mat.mes-hall hep-th math-ph math.MP nlin.SI


title: Minimal Simple de Sitter Solutions

abstract:
  We show that the minimal set of necessary ingredients to construct explicit,
four-dimensional de Sitter solutions from IIA string theory at tree-level are
O6-planes, non-zero Romans mass parameter, form fluxes, and negative internal
curvature. To illustrate our general results, we construct such minimal simple
de Sitter solutions from an orientifold compactification of compact hyperbolic
spaces. In this case there are only two moduli and we demonstrate that they are
stabilized to a sufficiently weakly coupled and large volume regime. We also
discuss generalizations of the scenario to more general metric flux
constructions.


title:
Torque anomalies at magnetization plateaux in quantum magnets with
  Dzyaloshinskii-Moriya interactions

abstract:
  We investigate the effect of Dzyaloshinskii-Moriya (DM) interactions on
torque measurements of quantum magnets with magnetization plateaux in the
context of a frustrated spin-1/2 ladder. Using extensive DMRG simulations, we
show that the DM contribution to the torque is peaked at the critical fields,
and that the total torque is non-monotonous if the DM interaction is large
enough compared to the g-tensor anisotropy. More remarkably, if the DM vectors
point in a principal direction of the g-tensor, torque measurements close to
this direction will show well defined peaks even for small DM interaction,
leading to a very sensitive way to detect the critical fields. We propose to
test this effect in the two-dimensional plateau system SrCu$_2$(BO$_3$)$_2$.


title: Euler-Mahonian distributions of type $B_n$

abstract:
  Adin, Brenti, and Roichman introduced the pairs of statistics $(\ndes,
\nmaj)$ and $(\fdes, \fmaj)$. They showed that these pairs are equidistributed
over the hyperoctahedral group $B_n$, and can be considered "Euler-Mahonian" in
that they generalize the Carlitz identity. Further, they asked whether there
exists a bijective proof of the equidistribution of their statistics. We give
such a bijection, along with a new proof of the generalized Carlitz identity.


title:
Electronic Phase Separation Transition as the Origin of the
  Superconductivity and the Pseudogap Phase of Cuprates

abstract:
  We propose a new phase of matter, an electronic phase separation transition
that starts near the upper pseudogap and segregates the holes into high and low
density domains. The Cahn-Hilliard approach is used to follow quantitatively
this second order transition. The resulting grain boundary potential confines
the charge in domains and favors the development of intragrain superconducting
amplitudes. The zero resistivity transition arises only when the intergrain
Josephson coupling $E_J$ is of the order of the thermal energy and phase
locking among the superconducting grains takes place. We show that this
approach explains the pseudogap and superconducting phases in a natural way and
reproduces some recent scanning tunneling microscopy data


title:
Classical Logical versus Quantum Conceptual Thought: Examples in
  Economics, Decision theory and Concept Theory

abstract:
  Inspired by a quantum mechanical formalism to model concepts and their
disjunctions and conjunctions, we put forward in this paper a specific
hypothesis. Namely that within human thought two superposed layers can be
distinguished: (i) a layer given form by an underlying classical deterministic
process, incorporating essentially logical thought and its indeterministic
version modeled by classical probability theory; (ii) a layer given form under
influence of the totality of the surrounding conceptual landscape, where the
different concepts figure as individual entities rather than (logical)
combinations of others, with measurable quantities such as 'typicality',
'membership', 'representativeness', 'similarity', 'applicability', 'preference'
or 'utility' carrying the influences. We call the process in this second layer
'quantum conceptual thought', which is indeterministic in essence, and contains
holistic aspects, but is equally well, although very differently, organized
than logical thought. A substantial part of the 'quantum conceptual thought
process' can be modeled by quantum mechanical probabilistic and mathematical
structures. We consider examples of three specific domains of research where
the effects of the presence of quantum conceptual thought and its deviations
from classical logical thought have been noticed and studied, i.e. economics,
decision theory, and concept theories and which provide experimental evidence
for our hypothesis.


title: Universality of Quantum Gravity Corrections

abstract:
  We show that the existence of a minimum measurable length and the related
Generalized Uncertainty Principle (GUP), predicted by theories of Quantum
Gravity, influence all quantum Hamiltonians. Thus, they predict quantum gravity
corrections to various quantum phenomena. We compute such corrections to the
Lamb Shift, the Landau levels and the tunnelling current in a Scanning
Tunnelling Microscope (STM). We show that these corrections can be interpreted
in two ways: (a) either that they are exceedingly small, beyond the reach of
current experiments, or (b) that they predict upper bounds on the quantum
gravity parameter in the GUP, compatible with experiments at the electroweak
scale. Thus, more accurate measurements in the future should either be able to
test these predictions, or further tighten the above bounds and predict an
intermediate length scale, between the electroweak and the Planck scale.


title: Quantum repeaters with imperfect memories: cost and scalability

abstract:
  Memory dephasing and its impact on the rate of entanglement generation in
quantum repeaters is addressed. For systems that rely on probabilistic schemes
for entanglement distribution and connection, we estimate the maximum
achievable rate per employed memory for our optimized partial nesting protocol.
We show that, for any given distance $L$, the polynomial scaling of rate with
distance can only be achieved if quantum memories with coherence times on the
order of $L/c$ or longer, with $c$ being the speed of light in the channel, are
available. The above rate degrades as a power of $\exp[-\sqrt{(L/c)/ \tau_c}]$
with distance when the coherence time $\tau_c \ll L/c$.


title: The Algorithmic Behaviour of the F5 Algorithm

abstract:
  This paper has been withdrawn due to an error in the proof of the termination
of the algorithm. Moreover, some ideas of this paper are a joint work with John
Perry and it is inappropriate to mention only me as an author. John Perry was
in spite of the statement in the acknowledgment of previous versions not
proofreading this paper. Recently we have found a new solution for ensuring
F5's termination, which can be found here : arXiv:1006.0318.


title:
Higher-order spin effects in the amplitude and phase of gravitational
  waveforms emitted by inspiraling compact binaries: Ready-to-use gravitational
  waveforms

abstract:
  We provide ready-to-use time-domain gravitational waveforms for spinning
compact binaries with precession effects through 1.5PN order in amplitude and
compute their mode decomposition using spin-weighted -2 spherical harmonics. In
the presence of precession, the gravitational-wave modes (l,m) contain
harmonics originating from combinations of the orbital frequency and precession
frequencies. We find that the gravitational radiation from binary systems with
large mass asymmetry and large inclination angle can be distributed among
several modes. For example, during the last stages of inspiral, for some
maximally spinning configurations, the amplitude of the (2,0) and (2,1) modes
can be comparable to the amplitude of the (2,2) mode. If the mass ratio is not
too extreme, the l=3 and l=4 modes are generally one or two orders of magnitude
smaller than the l = 2 modes. Restricting ourselves to spinning, non-precessing
compact binaries, we apply the stationary-phase approximation and derive the
frequency-domain gravitational waveforms including spin-orbit and spin(1)-
spin(2) effects through 1.5PN and 2PN order respectively in amplitude, and
2.5PN order in phase. Since spin effects in the amplitude through 2PN order
affect only the first and second harmonics of the orbital phase, they do not
extend the mass reach of gravitational-wave detectors. However, they can
interfere with other harmonics and lower or raise the signal-to-noise ratio
depending on the spin orientation. These ready-to-use waveforms could be
employed in the data-analysis of the spinning, inspiraling binaries as well as
in comparison studies at the interface between analytical and numerical
relativity.


title:
Extracting the rho resonance from lattice QCD simulations at small quark
  masses

abstract:
  Using established relations between the scattering matrix in infinite volume
and the two-particle spectrum in a periodic box, we compute the mass and width
of the rho meson from simulations of N_f=2 flavors of dynamical clover fermions
at small pion masses 2 m_pi < m_rho.


title:
The Effects of Substrate Phonon Mode Scattering on Transport in Carbon
  Nanotubes

abstract:
  Carbon nanotubes (CNTs) have large intrinsic carrier mobility due to weak
acoustic phonon scattering. However, unlike two-dimensional
metal-oxide-semiconductor field effect transistors (MOSFETs), substrate surface
polar phonon (SPP) scattering has a dramatic effect on the CNTFET mobility, due
to the reduced vertical dimensions of the latter. We find that for the Van der
Waals distance between CNT and an SiO$_2$ substrate, the low-field mobility at
room temperature is reduced by almost an order of magnitude depending on the
tube diameter. We predict additional experimental signatures of the SPP
mechanism in dependence of the mobility on density, temperature, tube diameter,
and CNT - substrate separation.


title:
High-Mobility Few-Layer Graphene Field Effect Transistors Fabricated on
  Epitaxial Ferroelectric Gate Oxides (Supplementary Information)

abstract:
  Supplementary Information to arXiv:0810.4466: 1. Characterizations of
Pb(Zr_0.2Ti_0.8)O_3 (PZT) films. 2. Substrate preparation before the
exfoliation of graphene. 3. The band structure of FLG. 4. Dielectric constant
measurements of PZT. 5. rho(V_g) and R_H(V_g) fitting inside the band overlap
regime. 6. The deformation potential of longitudinal acoustic (LA) phonons in
graphene. 7. Resistivity and Hall measurements of a SiO_2-gated FLG.


title: Interface evolution: water waves in 2-D

abstract:
  We study the free boundary evolution between two irrotational, incompressible
and inviscid fluids in 2-D without surface tension. We prove local-existence in
Sobolev spaces when, initially, the difference of the gradients of the pressure
in the normal direction has the proper sign, an assumption which is also known
as the Rayleigh-Taylor condition. The well-posedness of the full water wave
problem was first obtained by Wu \cite{Wu}. The methods introduced in this
paper allows us to consider multiple cases: with or without gravity, but also a
closed boundary or a periodic boundary with the fluids placed above and below
it. It is assumed that the initial interface does not touch itself, being a
part of the evolution problem to check that such property prevails for a short
time, as well as it does the Rayleigh-Taylor condition, depending conveniently
upon the initial data. The addition of the pressure equality to the contour
dynamic equations is obtained as a mathematical consequence, and not as a
physical assumption, from the mere fact that we are dealing with weak solutions
of Euler's equation in the whole space.


title:
The role of luminous substructure in the gravitational lens system MG
  2016+112

abstract:
  MG 2016+112 is a quadruply imaged lens system with two complete images A and
B and a pair of merging partial images in region C as seen in the radio. The
merging images are found to violate the expected mirror symmetry. This
indicates an astrometric anomaly which could only be of gravitational origin
and could arise due to substructure in the environment or line-of-sight of the
lens galaxy. We present new high resolution multi-frequency VLBI observations
at 1.7, 5 and 8.4 GHz. Three new components are detected in the new VLBI
imaging of both the lensed images A and B. The expected opposite parity of the
lensed images A and B was confirmed due to the detection of non-collinear
components. Furthermore, the observed properties of the newly detected
components are inconsistent with the predictions of previous mass models. We
present new scenarios for the background quasar which are consistent with the
new observations. We also investigate the role of the satellite galaxy situated
at the same redshift as the main lensing galaxy. Our new mass models
demonstrate quantitatively that the satellite galaxy is the primary cause of
the astrometric anomaly found in region C. The detected satellite is consistent
with the abundance of subhaloes expected in the halo from cold dark matter
(CDM) simulations. However, the fraction of the total halo mass in the
satellite as computed from lens modeling is found to be higher than that
predicted by CDM simulations.


title:
On The Use of Absorption Cells as a Wavelength Reference for Precision
  Radial Velocity Measurements in the Near Infrared

abstract:
  Considerable interest is now focused on the detection of terrestrial mass
planets around M dwarfs, and radial velocity surveys with high-resolution
spectrographs in the near infrared are expected to be able to discover such
planets. We explore the possibility of using commercially available molecular
absorption gas cells as a wavelength reference standard for high-resolution
fiber-fed spectrographs in the near-infrared. We consider the relative merits
and disadvantages of using such cells compared to Thorium-Argon emission lamps
and conclude that in the astronomical H band they are a viable method of
simultaneous calibration, yielding an acceptable wavelength calibration error
for most applications. Four well-characterized and commercially available
standard gas cells of HCN, 12C$_2$H$_2$, 12CO, and 13CO can together span over
120nm of the H band, making them suitable for use in astronomical
spectrographs. The use of isotopologues of these molecules can increase line
densities and wavelength coverage, extending their application to different
wavelength regions.


title: Dark energy, the electroweak vacua and collider phenomenology

abstract:
  Higher dimensional non-renormalizable operators may modify the Standard Model
Higgs potential in many interesting ways. Here, we consider the appearance of a
second vacuum which may play an important role in cosmology. For the certain
range of parameters, the usual second order electroweak phase transition is
followed by a first order phase transition that may drive the late time
accelerated expansion of the universe. Such a potential contains kink-like
solutions which in turn can play a crucial role in reconstructing the global
shape of the potential in colliders, as we explicitly demonstrate.


title: The PAMELA Positron Excess from Annihilations into a Light Boson

abstract:
  Recently published results from the PAMELA experiment have shown conclusive
evidence for an excess of positrons at high (~ 10 - 100 GeV) energies,
confirming earlier indications from HEAT and AMS-01. Such a signal is generally
expected from dark matter annihilations. However, the hard positron spectrum
and large amplitude are difficult to achieve in most conventional WIMP models.
The absence of any associated excess in anti-protons is highly constraining on
any model with hadronic annihilation modes. We revisit an earlier proposal,
whereby the dark matter annihilates into a new light (<~GeV) boson phi, which
is kinematically constrained to go to hard leptonic states, without
anti-protons or pi0's. We find this provides a very good fit to the data. The
light boson naturally provides a mechanism by which large cross sections can be
achieved through the Sommerfeld enhancement, as was recently proposed.
Depending on the mass of the WIMP, the rise may continue above 300 GeV, the
extent of PAMELA's ability to discriminate electrons and positrons.


title:
The evolution of two stellar populations in globular clusters I. The
  dynamical mixing timescale

abstract:
  We investigate the long-term dynamical evolution of two distinct stellar
populations of low-mass stars in globular clusters in order to study whether
the energy equipartition process can explain the high number of stars
harbouring abundance anomalies seen in globular clusters. We analyse N-body
models by artificially dividing the low-mass stars (m<0.9 Msun) into two
populations: a small number of stars (second generation) consistent with an
invariant IMF and with low specific energies initially concentrated towards the
cluster-centre mimic stars with abundance anomalies. These stars form from the
slow winds of fast-rotating massive stars. The main part of low-mass (first
generation) stars has the pristine composition of the cluster. We study in
detail how the two populations evolve under the influence of two-body elaxation
and the tidal forces due to the host galaxy.Stars with low specific energy
initially concentrated toward the cluster centre need about two relaxation
times to achieve a complete homogenisation throughout the cluster. For
realistic globular clusters, the number ratio between the two populations
increases only by a factor 2.5 due to the preferential evaporation of the
population of outlying first generation stars. We also find that the loss of
information on the stellar orbital angular momentum occurs on the same
timescale as spatial homogenisation.


title: Where in the String Landscape is Quintessence

abstract:
  We argue that quintessence may reside in certain corners of the string
landscape. It arises as a linear combination of internal space components of
higher rank forms, which are axion-like at low energies, and may mix with
4-forms after compactification of the Chern-Simons terms to 4D due to internal
space fluxes. The mixing induces an effective mass term, with an action which
{\it preserves} the axion shift symmetry, breaking it spontaneously after the
background selection. With several axions, several 4-forms, and a low string
scale, as in one of the setups already invoked for dynamically explaining a
tiny residual vacuum energy in string theory, the 4D mass matrix generated by
random fluxes may have ultralight eigenmodes over the landscape, which are
quintessence. We illustrate how this works in simplest cases, and outline how
to get the lightest mass to be comparable to the Hubble scale now, $H_0 \sim
10^{-33} {\rm eV}$. The shift symmetry protects the smallest mass from
perturbative corrections in field theory. Further, if the ultralight eigenmode
does not couple directly to any sector strongly coupled at a high scale, the
non-perturbative field theory corrections to its potential will also be
suppressed. Finally, if the compactification length is larger than the string
length by more than an order of magnitude, the gravitational corrections may
remain small too, even when the field value approaches $M_{Pl}$.


title: Algebraic spin liquid in an exactly solvable spin model

abstract:
  We have proposed an exactly solvable quantum spin-3/2 model on a square
lattice. Its ground state is a quantum spin liquid with a half integer spin per
unit cell. The fermionic excitations are gapless with a linear dispersion,
while the topological "vison" excitations are gapped. Moreover, the massless
Dirac fermions are stable. Thus, this model is, to the best of our knowledge,
the first exactly solvable model of half-integer spins whose ground state is an
"algebraic spin liquid."


title:
Low Mass Companions for Five Solar-Type Stars from the Magellan Planet
  Search Program

abstract:
  We report low mass companions orbiting five Solar-type stars that have
emerged from the Magellan precision Doppler velocity survey, with minimum
(Msini) masses ranging from 1.2 to 25 Mjup. These nearby target stars range
from mildly metal-poor to metal-rich, and appear to have low chromospheric
activity. The companions to the brightest two of these stars have previously
been reported from the CORALIE survey. Four of these companions (HD 48265-b, HD
143361-b, HD 28185-b, HD 111232-b) are low-mass Jupiter-like planets in
eccentric intermediate and long-period orbits. On the other hand, the companion
to HD 43848 appears to be a long period brown dwarf in a very eccentric orbit.


title: Monte Carlo discretization of general relativistic radiation transport

abstract:
  An indirect, hybrid Monte Carlo discretization of general relativistic
kinetic theory suitable for the development of numerical schemes for radiation
transport is presented. The discretization is based on surface flux estimators
obtained from a local decomposition of the distribution function, and can
handle optically thick regions by means of formal solutions within each cell.
Furthermore, the scheme is designed for parallel implementation, and it admits
the use of adaptive techniques by virtue of leaving all probability density
functions unspecified. Some considerations for numerical uses of the scheme are
discussed.


title: QCD radiation in the production of heavy colored particles at the LHC

abstract:
  We present a study of effects of QCD radiation in the production of heavy
colored states, employing inclusive multi-jet samples obtained by matching
matrix elements and parton showers. We discuss several examples showing that
matched samples are in general not only more accurate than a parton shower
alone, but also often indispensable to make reliable predictions of beyond the
Standard Model signals.


title: An Activity-Based Model for Separation of Duty

abstract:
  This paper offers several contributions for separation of duty (SoD)
administration in role-based access control (RBAC) systems. We first introduce
a new formal framework, based on business perspective, where SoD constraints
are analyzed introducing the activity concept. This notion helps organizations
define SoD constraints in terms of business requirements and reduces management
complexity in large-scale RBAC systems. The model enables the definition of a
wide taxonomy of conflict types. In particular, object-based SoD is introduced
using the SoD domain concept, namely the set of data in which transaction
conflicts may occur. Together with the formalization of the above properties,
in this paper we also show the effectiveness of our proposal: we have applied
the model to a large, existing organization; results highlight the benefits of
adopting the proposed model in terms of reduced administration cost.


title: Orthogonally additive holomorphic functions of bounded type over $C(K)$

abstract:
  It is known that all $k$-homogeneous orthogonally additive polynomials $P$
over $C(K)$ are of the form $$ P(x)=\int_K x^k d\mu . $$ Thus $x\mapsto x^k$
factors all orthogonally additive polynomials through some linear form $\mu$.
We show that no such linearization is possible without homogeneity. However, we
also show that every orthogonally additive holomorphic functions of bounded
type $f$ over $C(K)$ is of the form $$ f(x)=\int_K h(x) d\mu $$ for some $\mu$
and holomorphic $h\colon C(K) \to L^1(\mu)$ of bounded type.


title:
Photometric and Kinematic Characterization of Tidal Dwarf Galaxy
  candidates

abstract:
  Tidal Dwarf Galaxies (TDG), or self-graviting objects created from the tidal
forces in interacting galaxies, have been found in several merging systems.
This work will focus on identifying TDG candidates among a sample of Luminous
and Ultraluminous Infrared Galaxies (U)LIRGs, where these interactions are
occurring, in order to study their formation and evolution. High angular
resolution imaging from Hubble Space Telescope (HST) in B, I and H band will be
used to detect these sources. Photometric measurements of these regions
compared to Stellar Synthesis Population models will allow us to roughly
estimate the age and the mass. Complementary optical Integral Field
spectroscopy we will be able to explore the physical, kinematic and dynamical
properties in TDGs. We present preliminary photometric results for IRAS
0857+3915, as an example of the study that will be held for the entire sample
of (U)LIRGs.


title:
Thermodynamics of the Heusler alloy Co_2-xMn_1+xSi: a combined density
  functional theory and cluster expansion study

abstract:
  Previous studies indicated that intrinsic point defects play a crucial role
for the density of states of ferromagnetic half-metals in the band gap region:
At large concentrations, defect-derived bands might close the gap at the Fermi
energy in the minority spin channel. In this work, structural disorder in the
Co- and Mn-sublattices of the full Heusler alloy Co_2-xMn_1+xSi (-1 < x < 2) is
investigated with a cluster expansion approach, parametrized using all-electron
density functional theory calculations. By establishing two separate cluster
expansions, one for the formation energy and one for the total spin moment, we
are in position to determine the stability of different configurations, to
predict new (also half-metallic) ground states and to extend the known
Slater-Pauling rule for ideally stoichiometric Heusler alloys to
non-stoichiometric, Mn-rich compositions. This enables us to identify
potentially half-metallic structures in the Mn-rich region. With the help of
Monte Carlo simulations based on the cluster expansion, we establish
theoretically that Co_2-xMn_1+xSi close to the stoichiometric composition ought
to show a high degree of structural order in thermodynamic equilibrium. Hence,
samples prepared with the correct stoichiometry should indeed be half-metallic
after thermal annealing. Moreover, we predict that adding a small amount of Mn
to stoichiometric Co_2MnSi allows to suppress the thermally activated formation
of detrimental Co antisites. At Mn-rich compositions (x>1), the ordered ground
state structures predicted for zero temperature are found to be thermally
unstable and to decompose into Co2MnSi and Mn3Si above room temperature.


title:
N = 2 world-sheet approach to D-branes on generalized Kaehler
  geometries: I. General formalism

abstract:
  We present an N = 2 world-sheet superspace description of D-branes on
bihermitian or generalized Kaehler manifolds. To accomplish this, D-branes are
considered as boundary conditions for a nonlinear sigma-model in what we call N
= 2 boundary superspace. In this note the general formalism for such an
approach is presented and the resulting classification sketched. This includes
some remarks regarding target spaces whose parameterization includes
semi-chiral superfields which have not appeared in the literature yet. In an
accompanying note we turn to some examples and applications of the general
setup presented here.


title: Lattice refinement in loop quantum cosmology

abstract:
  Lattice refinement in LQC, its meaning and its necessity are discussed. The
r\^ole of lattice refinement for the realisation of a successful inflationary
model is explicitly shown. A simple and effective numerical technique to solve
the constraint equation for any choice of lattice refinement model is briefly
illustrated. Phenomenological and consistency requirements leading to a
particular choice of lattice refinement model are presented, while it is
subsequently proved that only this choice of lattice refinement leads to a
unique factor ordering in the Wheeler-De Witt equation, which is the continuum
limit of LQC.


title:
Study of multi-muon events produced in p-pbar collisions at sqrt(s)=1.96
  TeV

abstract:
  We report a study of multi-muon events produced at the Fermilab Tevatron
collider and recorded by the CDFII detector. In a data set acquired with a
dedicated dimuon trigger and corresponding to an integrated luminosity of 2100
pb^-1, we isolate a significant sample of events in which at least one of the
muon candidates is produced outside of the beam pipe of radius 1.5cm. The
production cross section and kinematics of events in which both muon candidates
are produced inside the beam pipe are successfully modeled by known QCD
processes which include heavy flavor production. In contrast, we are presently
unable to fully account for the number and properties of the remaining events,
in which at least one muon candidate is produced outside of the beam pipe, in
terms of the same understanding of the CDFII detector, trigger, and event
reconstruction. Several topological and kinematic properties of these events
are presented in this paper. These events offer a plausible resolution to
long-standing inconsistencies related to b-bbar production and decay.


title: Raman Spectroscopy of Graphene Edges

abstract:
  Graphene edges are of particular interest, since their chirality determines
the electronic properties. Here we present a detailed Raman investigation of
graphene flakes with well defined edges oriented at different crystallographic
directions. The position, width and intensity of G and D peaks at the edges are
studied as a function of the incident light polarization. The D-band is
strongest for light polarized parallel to the edge and minimum for
perpendicular orientation. Raman mapping shows that the D peak is localized in
proximity of the edge. The D to G ratio does not always show a significant
dependence on edge orientation. Thus, even though edges can appear
macroscopically smooth and oriented at well defined angles, they are not
necessarily microscopically ordered.


title: Probing the Nature of the Vela X Cocoon

abstract:
  Vela X is a pulsar wind nebula (PWN) associated with the active pulsar
B0833-45 and contained within the Vela supernova remnant (SNR). A collimated
X-ray filament ("cocoon") extends south-southwest from the pulsar to the center
of Vela X. VLA observations uncovered radio emission coincident with the
eastern edge of the cocoon and H.E.S.S. has detected TeV $\gamma$-ray emission
from this region as well. Using XMM-\textit{Newton} archival data, covering the
southern portion of this feature, we analyze the X-ray properties of the
cocoon. The X-ray data are best fit by an absorbed nonequilibrium plasma model
with a powerlaw component. Our analysis of the thermal emission shows enhanced
abundances of O, Ne, and Mg within the cocoon, indicating the presence of
ejecta-rich material from the propagation of the SNR reverse shock, consistent
with Vela X being a disrupted PWN. We investigate the physical processes that
excite the electrons in the PWN to emit in the radio, X-ray and $\gamma$-ray
bands. The radio and non-thermal X-ray emission can be explained by synchrotron
emission. We model the $\gamma$-ray emission by Inverse Compton scattering of
electrons off of cosmic microwave background (CMB) photons. We use a
3-component broken power law to model the synchrotron emission, finding an
intrinsic break in the electron spectrum at $\sim5 \times 10^{6}$ keV and a
cooling break at $\sim$ 5.5 $\times 10^{10}$ keV. This cooling break along with
a magnetic field strength of 5 $\times 10^{-6}$ G indicate that the synchrotron
break occurs at $\sim$1 keV.


title: Weakly Turbulent MHD Waves in Compressible Low-Beta Plasmas

abstract:
  In this Letter, weak turbulence theory is used to investigate interactions
among Alfven waves and fast and slow magnetosonic waves in collisionless
low-beta plasmas. The wave kinetic equations are derived from the equations of
magnetohydrodynamics, and extra terms are then added to model collisionless
damping. These equations are used to provide a quantitative description of a
variety of nonlinear processes, including "parallel" and "perpendicular" energy
cascade, energy transfer between wave types, "phase mixing," and the generation
of back-scattered Alfven waves.


title: Probing nonstandard interactions with reactor neutrinos

abstract:
  New limits on the weak mixing angle and on the electron neutrino effective
charge radius in the low energy regime, below 100 MeV, are obtained from a
combined fit of all electron-(anti)neutrino electron elastic scattering
measurements. We have included the recent TEXONO measurement with a CsI (Tl)
detector. Only statistical error of this measurement has been taken into
account. Weak mixing angle is found to be sin^2 theta_W = 0.255 +0.022 -0.023.
The electron neutrino effective charge radius squared is bounded to be r^2 =
(0.9 +0.9 -1.0) x 10^{-32} cm^2. The sensitivity of future low energy neutrino
experiments to nonstandard interactions of neutrinos with quarks is also
discussed.


title:
Convergent and divergent numbers games for certain collections of
  edge-weighted graphs

abstract:
  The numbers game is a one-player game played on a finite simple graph with
certain "amplitudes" assigned to its edges and with an initial assignment of
real numbers to its nodes. The moves of the game successively transform the
numbers at the nodes using the amplitudes in a certain way. Here, the edge
amplitudes will be negative integers. Combinatorial methods are used to
investigate the convergence and divergence of numbers games played on certain
such graphs. The results obtained here provide support for results in a
companion paper.


title: A note on spectral triples and quasidiagonality

abstract:
  Spectral triples (of compact type) are constructed on arbitrary separable
quasidiagonal C*-algebras. On the other hand an example of a spectral triple on
a non-quasidiagonal algebra is presented.


title: The C$^*$-envelope of a semicrossed product and Nest Representations

abstract:
  Let $X$ be compact Hausdorff, and $\phi: X \to X$ a continuous surjection.
Let $\mathcal{A}$ be the semicrossed product algebra corresponding to the
relation fU = Uf\circ \phi$ or to the relation $Uf = f\circ \phi U.$ Then the
C$^*$-envelope of $\mathcal{A}$ is the crossed product of a commutative
C$^*$-algebra which contains $C(X)$ as a subalgebra, with respect to a
homeomorphism which we construct. We also show there are"sufficiently many"
nest representations.


title: Blasting through lattice calculations using CUDA

abstract:
  Modern graphics hardware is designed for highly parallel numerical tasks and
provides significant cost and performance benefits. Graphics hardware vendors
are now making available development tools to support general purpose high
performance computing. Nvidia's CUDA platform, in particular, offers direct
access to graphics hardware through a programming language similar to C. Using
the CUDA platform we have implemented a Wilson-Dirac operator which runs at an
effective 68 Gflops on the Tesla C870. The recently released GeForce GTX 280
runs this same code at 92 Gflops, and we expect further improvement pending
code optimization.


title:
On unitary unipotent representations of $p$-adic groups and affine Hecke
  algebras with unequal parameters

abstract:
  We determine the unitary dual of the geometric graded Hecke algebras with
{unequal} parameters which appear in Lusztig's classification of unipotent
representations for {exceptional} $p$-adic groups. The largest such algebra is
of type $F_4.$ Via the Barbasch-Moy correspondence of unitarity applied to this
setting, this is equivalent to the identification of the corresponding unitary
unipotent representations with real central character of the $p$-adic groups.
In order for this correspondence to be applicable here, we show (following
Lusztig's geometric classification, and Barbasch and Moy's original argument)
that the set of tempered modules with real central character for a geometric
graded Hecke algebra is linearly independent when restricted to the Weyl group.


title:
Coarse grained Density Functional theory of order-disorder phase
  transitions in metallic alloys

abstract:
  The technological performances of metallic compounds are largely influenced
by atomic ordering. Although there is a general consensus that successful
theories of metallic systems should account for the quantum nature of the
electronic glue, existing non-perturbative high-temperature treatments are
based on effective classical atomic Hamiltonians. We propose a solution for the
above paradox and offer a fully quantum mechanical, though approximate, theory
that on equal footing deals with both electrons and ions. By taking advantage
of a coarse grained formulation of the density functional theory [Bruno et al.,
Phys. Rev. B 77, 155108 (2008)] we develop a MonteCarlo technique, based on an
ab initio Hamiltonian, that allows for the efficient evaluation of finite
temperature statistical averages. Calculations of the relevant thermodynamic
quantities and of the electronic structures for CuZn and Ni$_3$V support that
our theory provides an appropriate description of order-disorder phase
transitions.


title: Bulk superconductivity and disorder in single crystals of LaFePO

abstract:
  We have studied the intrinsic normal and superconducting properties of the
oxypnictide LaFePO. These samples exhibit bulk superconductivity and the
evidence suggests that stoichiometric LaFePO is indeed superconducting, in
contrast to other reports. We find that superconductivity is independent of the
interplane residual resistivity $\rho_0$ and discuss the implications of this
on the nature of the superconducting order parameter. Finally we find that,
unlike $T_c$, other properties in single-crystal LaFePO including the
resistivity and magnetoresistance, can be very sensitive to disorder.


title:
d-wave to s-wave to normal metal transitions in disordered
  superconductors

abstract:
  We study suppression of superconductivity by disorder in d-wave
superconductors, and predict the existence of (at least) two sequential low
temperature transitions as a function of increasing disorder: a d -wave to
-wave, and then an s-wave to metal transition. This is a universal property of
the system which is independent of the sign of the interaction constant in the
s-channel


title:
Direct Calculation of the Turbulent Dissipation Efficiency in Anelastic
  Convection

abstract:
  The current understanding of the turbulent dissipation in stellar convective
zones is based on the assumption that the turbulence follows Kolmogorov
scaling. This assumption is valid for some cases in which the time frequency of
the external shear is high (e.g., solar p modes). However, for many cases of
astrophysical interest (e.g., binary orbits, stellar pulsations, etc.), the
timescales of interest lie outside the regime of applicability of Kolmogorov
scaling. We present direct calculations of the dissipation efficiency of the
turbulent convective flow in this regime, using simulations of anelastic
convection with external forcing. We show that the effects of the turbulent
flow are well represented by an effective viscosity coefficient, we provide the
values of the effective viscosity as a function of the perturbation frequency
and compare our results to the perturbative method for finding the effective
viscosity of Penev et al. that can be applied to actual simulations of the
surface convective zones of stars.


title: The numbers game and Dynkin diagram classification results

abstract:
  The numbers game is a one-player game played on a finite simple graph with
certain "amplitudes" assigned to its edges and with an initial assignment of
real numbers to its nodes. The moves of the game successively transform the
numbers at the nodes using the amplitudes in a certain way. Combinatorial
reasoning is used to show that those connected graphs with negative integer
amplitudes for which the numbers game meets a certain finiteness requirement
are precisely the Dynkin diagrams associated with the finite-dimensional
complex simple Lie algebras. This strengthens a result originally due to the
second author. A more general result is obtained when certain real number
amplitudes are allowed. The resulting graphs are in families, each family
corresponding to a finite irreducible Coxeter group. These results are used to
demonstrate that the only generalized Cartan matrices for which there exist
finite edge-colored ranked posets enjoying a certain structure property are the
Cartan matrices for the finite-dimensional complex semisimple Lie algebras. In
this setting, classifications of the finite-dimensional Kac--Moody algebras and
of the finite Coxeter and Weyl groups are re-derived.


title:
Collisional heating as the origin of filament emission in galaxy
  clusters

abstract:
  [Abridged] Photoionization, whether by starlight or other sources, has
difficulty in accounting for the observed spectra of the optical filaments that
often surround central galaxies in large clusters. Our first paper examined
whether heating by energetic particles or dissipative MHD wave can account for
the observations. Here we include atomic and low-ionization regions. The model
of the hydrogen atom, along with all elements of the H-like iso-electronic
sequence, is now fully nl-resolved. We show how the predicted HI spectrum
differs from the pure recombination case. The second update is to the rates for
H^0 - H2 inelastic collisions. We now use the values computed by Wrathmall et
al. The rates are often much larger.
  We calculate the chemistry, ionization, temperature, gas pressure, and
emission-line spectrum for a wide range of gas densities and collisional
heating rates. We assume that the filaments are magnetically confined and free
to move along field lines so that the gas pressure is equal to that of the
surrounding hot gas. A mix of clouds, some being dense and cold and others hot
and tenuous, can exist. The observed spectrum will be the integrated emission
from clouds with different densities and temperatures but the same pressure. We
assume that the gas filling factor is given by a power law in density. The
power-law index is set by matching the observed intensities of IR H2 lines
relative to optical HI lines. We conclude that the filaments are heated by
ionizing particles, either conducted in from surrounding regions or produced in
situ by processes related to MHD waves.


title: Divisors in the moduli spaces of curves

abstract:
  In this mostly expository paper we review several known results about the
cohomology of moduli spaces of smooth and stable curves, focusing in particular
on low degree cohomology. We also give a new proof of Harer's theorem
describing the second cohomology group of the moduli space of smooth n-pointed
curves of given genus


title: Star formation triggered by SNR impact into magnetized neutral clouds

abstract:
  Considering the physical conditions that are relevant for triggering star
formation in interactions involving SN shocks and neutral clouds, we have built
diagrams of the SNR radius versus the cloud density in which these conditions
constrain a shaded zone where star formation is allowed. The diagrams are also
tested with fully 3-D MHD radiative cooling simulations involving a SNR and a
self-gravitating cloud and we find that the numerical analysis is consistent
with the results predicted by the diagrams. While the inclusion of a
homogeneous magnetic field approximately perpendicular to the impact velocity
of the SNR with an intensity ~1 $mu$G results only a small shrinking of the
star formation zone in the diagrams, a larger magnetic field (~10 $\mu$G)
causes a significant shrinking, as expected. Applications of our results to
real star formation regions in our own galaxy have revealed that their
formation could have been triggered by a SN shock wave. Finally, we have
evaluated the effective global star formation efficiency of this sort of
interactions and found that it is smaller than the observed values in our
Galaxy (SFE ~0.01-0.3). This result is consistent with previous work in the
literature and also suggests that the mechanism presently investigated, though
very powerful to drive structure formation, supersonic turbulence and
eventually, local star formation, does not seem to be sufficient to drive
global star formation in normal star forming galaxies.


title: Interactive Proofs For Quantum Computations

abstract:
  The widely held belief that BQP strictly contains BPP raises fundamental
questions: Upcoming generations of quantum computers might already be too large
to be simulated classically. Is it possible to experimentally test that these
systems perform as they should, if we cannot efficiently compute predictions
for their behavior? Vazirani has asked: If predicting Quantum Mechanical
systems requires exponential resources, is QM a falsifiable theory? In
cryptographic settings, an untrusted future company wants to sell a quantum
computer or perform a delegated quantum computation. Can the customer be
convinced of correctness without the ability to compare results to predictions?
  To answer these questions, we define Quantum Prover Interactive Proofs
(QPIP). Whereas in standard Interactive Proofs the prover is computationally
unbounded, here our prover is in BQP, representing a quantum computer. The
verifier models our current computational capabilities: it is a BPP machine,
with access to few qubits. Our main theorem can be roughly stated as: "Any
language in BQP has a QPIP, and moreover, a fault tolerant one". We provide two
proofs. The simpler one uses a new (possibly of independent interest) quantum
authentication scheme (QAS) based on random Clifford elements. This QPIP
however, is not fault tolerant. Our second protocol uses polynomial codes QAS
due to BCGHS, combined with quantum fault tolerance and multiparty quantum
computation techniques. A slight modification of our constructions makes the
protocol "blind": the quantum computation and input are unknown to the prover.
  After we have derived the results, we have learned that Broadbent at al. have
independently derived "universal blind quantum computation" using completely
different methods. Their construction implicitly implies similar implications.


title:
Median structures on asymptotic cones and homomorphisms into mapping
  class groups

abstract:
  The main goal of this paper is a detailed study of asymptotic cones of the
mapping class groups. In particular, we prove that every asymptotic cone of a
mapping class group has a bi-Lipschitz equivariant embedding into a product of
real trees, sending limits of hierarchy paths onto geodesics, and with image a
median subspace. One of the applications is that a group with Kazhdan's
property (T) can have only finitely many pairwise non-conjugate homomorphisms
into a mapping class group. We also give a new proof of the rank conjecture of
Brock and Farb (previously proved by Behrstock and Minsky, and independently by
Hamenstaedt).


title: Brane cosmology in the Horava-Witten heterotic M-Theory on $S^{1}/Z_{2}$

abstract:
  We study the radion stability and radion mass in the framework of the
Horava-Witten (HW) heterotic M-Theory on $S^{1}/Z_{2}$, and find that the
radion is stable and its mass can be of the order of GeV. The gravity is
localized on the visible brane, and the spectrum of the gravitational
Kaluza-Klein (KK) modes is discrete and can have a mass gap of TeV. The
corrections to the 4D Newtonian potential from the higher order gravitational
KK modes are exponentially suppressed. Applying such a setup to cosmology, we
find the generalized Friedmann-like equations on each of the two orbifold
branes.


title:
Electric dipole moment searches: Effect of linear electric field
  frequency shifts induced in confined gases, II

abstract:
  The next generation of particle edm searches will be at such a high
sensitivity that it will be possible for the results to be contaminated by a
systematic error resulting from the interaction of the motional (E x v/c)
magnetic field with stray field gradients. In this paper we extend previous
work to present an analytic form for the frequency shift in the case of a
rectangular storage vessel and discuss the implications of the result for the
neutron edm experiment which will be installed at the SNS (Spallation Neutron
Source) by the LANL collaboration


title:
Quantization of the Myers-Pospelov model: the photon sector interacting
  with standard fermions as a perturbation of QED

abstract:
  We study the quantization of the electromagnetic sector of the Myers-Pospelov
model coupled to standard fermions. Our main objective, based upon experimental
and observational evidence, is to construct an effective theory which is a
genuine perturbation of QED, such that setting zero the Lorentz invariance
violation parameters will reproduce it. To this end we provide a physically
motivated prescription, based on the effective character of the model,
regarding the way in which the model should be constructed and how the QED
limit should be approached. This amounts to the introduction of an additional
coarse-graining physical energy scale $M$, under which we can trust the
effective field theory formulation. The prescription is successfully tested in
the calculation of the Lorentz invariance violating contributions arising from
the electron self-energy. Such radiative corrections turn out to be properly
scaled by very small factors for any reasonable values of the parameters and no
fine-tuning problems are found. Microcausality violations are highly suppressed
and occur only in a space-like region extremely close to the light-cone. The
stability of the model is guaranteed by restricting to concordant frames
satisfying $1-|\mathbf{v}_{max}|> 6.5\times10^{-11}$.


title:
The critical dimension for a fourth order elliptic problem with singular
  nonlinearity

abstract:
  We study the regularity of the extremal solution of the semilinear biharmonic
equation $\bi u=\f{\lambda}{(1-u)^2}$, which models a simple
Micro-Electromechanical System (MEMS) device on a ball $B\subset\IR^N$, under
Dirichlet boundary conditions $u=\partial_\nu u=0$ on $\partial B$. We complete
here the results of F.H. Lin and Y.S. Yang \cite{LY} regarding the
identification of a "pull-in voltage" $\la^*>0$ such that a stable classical
solution $u_\la$ with $0<u_\la<1$ exists for $\la\in (0,\la^*)$, while there is
none of any kind when $\la>\la^*$. Our main result asserts that the extremal
solution $u_{\lambda^*}$ is regular $(\sup_B u_{\lambda^*} <1)$ provided $ N
\le 8$ while $u_{\lambda^*} $ is singular ($\sup_B u_{\lambda^*} =1$) for $N
\ge 17$, in which case $1-C_0|x|^{4/3}\leq u_{\lambda^*} (x) \leq 1-|x|^{4/3}$
on the unit ball, where $ C_0:= <(\frac{\lambda^*}{\bar{\lambda}}>)^{1/3}$ and
$ \bar{\lambda}:= \frac{8 (N-{2/3}) (N- {8/3})}{9}$. The singular character of
the extremal solution for the remaining cases (i.e., when $9\leq N\leq 16$)
requires a computer assisted proof and will not be addressed in this paper.


title:
Simulating neurobiological localization of acoustic signals based on
  temporal and volumetric differentiations

abstract:
  The localization of sound sources by the human brain is computationally
simulated from a neurobiological perspective. The simulation includes the
neural representation of temporal differences in acoustic signals between the
ipsilateral and contralateral ears for constant sound intensities (angular
localization), and of volumetric differences in acoustic signals for constant
azimuthal angles (radial localization). The transmission of the original
acoustic signal from the environment, through each significant stage of
intermediate neurons, to the primary auditory cortex, is also simulated. The
errors that human brains make in attempting to localize sounds in
evolutionarily uncommon environments (such as when one ear is in water and one
ear is in air) are then mathematically predicted. A basic overview of the
physiology behind sound localization in the brain is also provided.


title:
Interferometric Studies of the extreme binary, $\epsilon$ Aurigae:
  Pre-eclipse Observations

abstract:
  We report new and archival K-band interferometric uniform disk diameters
obtained with the Palomar Testbed Interferometer for the eclipsing binary star
$\epsilon$ Aurigae, in advance of the start of its eclipse in 2009. The
observations were inteded to test whether low amplitude variations in the
system are connected with the F supergiant star (primary), or with the
intersystem material connecting the star with the enormous dark disk
(secondary) inferred to cause the eclipses. Cepheid-like radial pulsations of
the F star are not detected, nor do we find evidence for proposed 6% per decade
shrinkage of the F star. The measured 2.27 +/- 0.11 milli-arcsecond K band
diameter is consistent with a 300 times solar radius F supergiant star at the
Hipparcos distance of 625 pc. These results provide an improved context for
observations during the 2009-2011 eclipse.


title:
Molecular Brownian motion and invariance group of the Bogolyubov
  equation

abstract:
  Statistics of molecular random walks in a fluid is considered with the help
of Bogolyubov equation for generating functional of distribution functions. An
invariance group of this equation is found. It results in many exact relations
between path probability distribution of a test particle and its correlations
with the fluid. As the consequence, significant restrictions on possible shape
of the path distribution do arise. In particular, the hypothetical Gaussian
form of long-range asymptotic proves to be forbidden, even (and first of all)
under the Boltzmann-Grad limit. An allowed diffusive asymptotic possesses
power-law long tail (cut off by free flight length).


title: Distended Topologically Massive Electrodynamics

abstract:
  We extend topologically massive electrodynamics, both by adding a higher
derivative action to cast the entire three-term model in Chern-Simons (CS)
form, and by embedding it in an AdS background. It can then be written as the
sum of two CS terms, one of which vanishes at the "chiral" point, in analogy
with its gravitational topologically massive counterpart. Separately we treat
pure CS electrodynamics plus Einstein gravity interacting with point sources.
The gravity/vector field equations decouple; their solutions are the familiar
exterior "conical" metric and vector potentials.


title:
Thermodynamical properties of QED in 1+1 dimensions within light front
  dynamics

abstract:
  We investigate thermodynamical properties of quantum electrodynamics in 1+1
dimensions. Discrete light cone quantization is used to compute the partition
function of the canonical ensemble and the thermodynamical potential. The
potential is evaluated for different system sizes and coupling strengths. We
perform the continuum limit and the thermodynamical limit and present basic
thermodynamical quantities as a function of temperature for the interacting
system. A more accurate estimation of low lying bound state masses at
non-perturbative coupling strength are determined due to the higher harmonic
resolution.


title:
Iwahori-Hecke type algebras associated with the Lie superalgebras
  A(m,n), B(m,n), C(n) and D(m,n)

abstract:
  In this paper we give Iwahori-Hecke type algebras H_q(g) associated with the
Lie superalgebras g=A(m,n), B(m,n), C(n) and D(m,n). We classify the
irreducible representations of H_q(g) for generic q.


title:
Extended Slow-Roll Conditions and Primordial Fluctuations: Multiple
  Scalar Fields and Generalized Gravity

abstract:
  As an extension of our previous study, we derive slow-roll conditions for
multiple scalar fields which are non-minimally coupled with gravity and for
generalized gravity theories of the form $f(\phi,R)$. We provide simple
formulae of the spectral indices of scalar/tensor perturbations in terms of the
slow-roll parameters.


title: 'Tilting' the Universe with the Landscape Multiverse: The 'Dark' Flow

abstract:
  The theory for the selection of the initial state of the universe from the
landscape multiverse predicts superhorizon inhomogeneities induced by nonlocal
entanglement of our Hubble volume with modes and domains beyond the horizon.
Here we show these naturally give rise to a bulk flow with correlation length
of order horizon size. The modification to the gravitational potential has a
characteristic scale $L_{1} \simeq 10^{3} H^{-1}$, and it originates from the
preinflationary remnants of the landscape. The 'tilt' in the potential induces
power to the lowest CMB multipoles, with the dominant contribution being the
dipole and next, the quadrupole. The induced multipoles $l \le 2$ are aligned
with an axis normal to their alignment plane being oriented along the preferred
frame determined by the dipole. The preferred direction is displayed by the
velocity field of the bulk flow relative to the expansion frame of the
universe. The parameters are tightly constrained thus the derived modifications
lead to robust predictions for testing our theory. The 'dark' flow was recently
discovered by Kashlinsky et al. to be about $700 km/s$ which seems in good
agreement with our predictions for the induced dipole of order $3 \mu K$.
Placed in this context, the discovery of the bulk flow by Kashlinsky et al.
becomes even more interesting as it may provide a probe of the preinflationary
physics and a window onto the landscape multiverse.


title:
On the chain length dependence of local correlations in polymer melts
  and a perturbation theory of symmetric polymer blends

abstract:
  The self-consistent field (SCF) theory of dense polymer liquids assumes that
short-range correlations are almost independent of how monomers are connected
into polymers. Some limits of this idea are explored in the context of a
perturbation theory for mixtures of structurally identical polymer species, A
and B, in which the AB pair interaction differs slightly from the AA and BB
interaction, and the difference is controlled by a parameter alpha Expanding
the free energy to O(\alpha) yields an excess free energy of the form alpha
$z(N)\phi_{A}\phi_{B}$, in both lattice and continuum models, where z(N) is a
measure of the number of inter-molecular near neighbors of each monomer in a
one-component liquid. This quantity decreases slightly with increasing N
because the self-concentration of monomers from the same chain is slightly
higher for longer chains, creating a deeper correlation hole for longer chains.
We analyze the resulting $N$-dependence, and predict that $z(N) = z^{\infty}[1
+ \beta \bar{N}^{-1/2}]$, where $\bar{N}$ is an invariant degree of
polymerization, and $\beta=(6/\pi)^{3/2}$. This and other predictions are
confirmed by comparison to simulations. We also propose a way to estimate the
effective interaction parameter appropriate for comparisons of simulation data
to SCF theory and to coarse-grained theories of corrections to SCF theory,
which is based on an extrapolation of coefficients in this perturbation theory
to the limit $N \to \infty$. We show that a renormalized one-loop theory
contains a quantitatively correct description of the $N$-dependence of local
structure studied here.


title: Renormalized one-loop theory of correlations in polymer blends

abstract:
  The renormalized one-loop theory is a coarse-grained theory of corrections to
the self-consistent field theory (SCFT) of polymer liquids, and to the random
phase approximation (RPA) theory of composition fluctuations. We present
predictions of corrections to the RPA for the structure function $S(k)$ and to
the random walk model of single-chain statics in binary homopolymer blends. We
consider an apparent interaction parameter $\chi_{a}$ that is defined by
applying the RPA to the small $k$ limit of $S(k)$. The predicted deviation of
$\chi_{a}$ from its long chain limit is proportional to $N^{-1/2}$, where $N$
is chain length. This deviation is positive (i.e., destabilizing) for weakly
non-ideal mixtures, with $\chi_{a} N \alt 1$, but negative (stabilizing) near
the critical point. The positive correction to $\chi_{a}$ for low values of
$\chi_{a} N$ is a result of the fact that monomers in mixtures of shorter
chains are slightly less strongly shielded from intermolecular contacts. The
depression in $\chi_{a}$ near the critical point is a result of long-wavelength
composition fluctuations. The one-loop theory predicts a shift in the critical
temperature of ${\cal O}(N^{-1/2})$, which is much greater than the predicted
${\cal O}(N^{-1})$ width of the Ginzburg region. Chain dimensions deviate
slightly from those of a random walk even in a one-component melt, and contract
slightly with increasing $\chi_{e}$. Predictions for $S(k)$ and single-chain
properties are compared to published lattice Monte Carlo simulations.


title:
Vortex core switching by coherent excitation with single in-plane
  magnetic field pulses

abstract:
  The bistability of the core magnetization of nano-scaled magnets with a
magnetic vortex configuration has great potential for data storage
applications. To exploit this, reliable switching between the two possible
states is needed. Time resolved x-ray microscopy was used to study the response
of the vortex core to excitation pulses at sub-ns timescales and image the
vortex core switching. A reliable switching process by coherent excitation with
leading and trailing edges of in-plane magnetic field pulses was found and
compared with micromagnetic simulations.


title: Geodesic Webs on a Two-Dimensional Manifold and Euler Equations

abstract:
  We prove that any planar 4-web defines a unique projective structure in the
plane in such a way that the leaves of the foliations are geodesics of this
projective structure. We also find conditions for the projective structure
mentioned above to contain an affine symmetric connection, and conditions for a
planar 4-web to be equivalent to a geodesic 4-web on an affine symmetric
surface. Similar results are obtained for planar d-webs, d > 4, provided that
additional d-4 second-order invariants vanish.


title:
Multiwavelength study of the bright X-ray source population in the
  interacting galaxies NGC5774/NGC5775

abstract:
  A few nearby interacting galaxies are known that host elevated number of
ultraluminous X-ray sources. Here we report the results of a multiwavelength
study of the X-ray source population in the field of the interacting pair of
galaxies NGC5774/NGC5775. A total of 49 discrete sources are detected,
including 12 ultraluminous X-ray source candidates. X-ray source positions are
mapped onto optical and radio images to search for potential counterparts.
Twelve sources in the field have optical counterparts. Optical colors are used
to differentiate these sources, which are mostly located outside the optical
extent of the interacting galaxies, as potential globular clusters (2), one
compact blue dwarf galaxy and quasars (5). We obtained optical spectra of two
of the latter, which confirm that they are background quasars. We expect 3
background sources in the field of these two galaxies. These results are used
to determine the true X-ray population of these two interacting galaxies, which
are connected with two bridges. Two high mass X-ray binaries are detected on
these two bridges suggesting their formation through the interaction-induced
starformation episode.


title: Disordered Systems and the Replica Method in AdS/CFT

abstract:
  We formulate a holographic description of effects of disorder in conformal
field theories based on the replica method and the AdS/CFT correspondence.
Starting with $n$ copies of conformal field theories, randomness with a
gaussian distribution is described by a deformation of double trace operators.
After computing physical quantities, we take the $n \to 0$ limit at the final
step. We compute correlation functions in the disordered systems by using the
holographic replica method as well as the formulation in the conformal field
theory. We find examples where disorder changes drastically the scaling of two
point functions. The renormalization group flow of the effective central charge
in our disordered systems is also discussed.


title:
Ising vectors in the vertex operator algebra $V_{\Lambda}^+$ associated
  with the Leech lattice $\Lambda$

abstract:
  In this article, we study the Ising vectors in the vertex operator algebra
$V_\Lambda^+$ associated with the Leech lattice $\Lambda$. The main result is a
characterization of the Ising vectors in $V_\Lambda^+$. We show that for any
Ising vector $e$ in $V_\Lambda^+$, there is a sublattice $E\cong \sqrt{2}E_8$
of $\Lambda$ such that $e\in V_E^+$. Some properties about their corresponding
$\tau$-involutions in the moonshine vertex operator algebra $V^\natural$ are
also discussed. We show that there is no Ising vector of $\sigma$-type in
$V^\natural$. Moreover, we compute the centralizer $C_{\aut V^\natural}(z,
\tau_e)$ for any Ising vector $e\in V_\Lambda^+$, where $z$ is a 2B element in
$\aut V^\natural$ which fixes $V_\Lambda^+$. Based on this result, we also
obtain an explanation for the 1A case of an observation by Glauberman-Norton
(2001), which describes some mysterious relations between the centralizer of
$z$ and some 2A elements commuting $z$ in the Monster and the Weyl groups of
certain sublattices of the root lattice of type $E_8$ .


title: Doubly heavy baryons in QCD sum rules

abstract:
  The mass spectra of doubly heavy baryons are systematically calculated in the
framework of QCD sum rules. With a tentative heavy-diquark--light-quark
configuration, the interpolating currents representing the doubly heavy baryons
are proposed. Contributions of the operators up to dimension six are included
in operator product expansion. The numerical results are compatible with other
theoretical predictions, which may support the $(QQ)-(q)$ structure of doubly
heavy baryons.


title: Dark Matter through the Axion Portal

abstract:
  Motivated by the galactic positron excess seen by PAMELA and ATIC/PPB-BETS,
we propose that dark matter is a TeV-scale particle that annihilates into a
pseudoscalar "axion." The positron excess and the absence of an anti-proton or
gamma ray excess constrain the axion mass and branching ratios. In the simplest
realization, the axion is associated with a Peccei-Quinn symmetry, in which
case it has a mass around 360-800 MeV and decays into muons. We present a
simple and predictive supersymmetric model implementing this scenario, where
both the Higgsino and dark matter obtain masses from the same source of
TeV-scale spontaneous symmetry breaking.


title: Toward homochiral protocells in noncatalytic peptide systems

abstract:
  The activation-polymerization-epimerization-depolymerization (APED) model of
Plasson et al. has recently been proposed as a mechanism for the evolution of
homochirality on prebiotic Earth. The dynamics of the APED model in
two-dimensional spatially-extended systems is investigated for various
realistic reaction parameters. It is found that the APED system allows for the
formation of isolated homochiral proto-domains surrounded by a racemate. A
diffusive slowdown of the APED network such as induced through tidal motion or
evaporating pools and lagoons leads to the stabilization of homochiral bounded
structures as expected in the first self-assembled protocells.


title:
An axiomatic characterization of a two-parameter extended relative
  entropy

abstract:
  The uniqueness theorem for a two-parameter extended relative entropy is
proven. This result extends our previous one, the uniqueness theorem for a
one-parameter extended relative entropy, to a two-parameter case. In addition,
the properties of a two-parameter extended relative entropy are studied.


title: Correlations, Bell Inequality Violation & Quantum Entanglement

abstract:
  It is one of the most remarkable features of quantum physics that
measurements on spatially separated systems cannot always be described by a
locally causal theory. In such a theory, the outcomes of local measurements are
determined in advance solely by some unknown (or hidden) variables and the
choice of local measurements. Correlations that are allowed within the
framework of a locally causal theory are termed classical. Typically, the fact
that quantum mechanics does not always result in classical correlations is
revealed by the violation of Bell inequalities, which are constraints that have
to be satisfied by any classical correlations. It has been known for a long
time that entanglement is necessary to demonstrate nonclassical correlations,
and hence a Bell inequality violation. However, since some entangled quantum
states are known to admit explicit locally causal models, the exact role of
entanglement in Bell inequality violation has remained obscure. This thesis
provides both a comprehensive review on these issues as well as a report on new
discoveries made to clarify the relationship between entanglement and Bell
inequality violation.


title: Dark Matter Related to Axion and Axino

abstract:
  I discuss the essential features of the QCD axion: the strong CP solution and
hence its theoretical necessity. I also review the axion and axino effects on
astrophysics and cosmology, in particular with emphasis on their role in the
dark matter component in the universe.


title:
Admittance and noise in an electrically driven nano-structure: Interplay
  between quantum coherence and statistics

abstract:
  We investigate the interplay between the quantum coherence and statistics in
electrically driven nano-structures. We obtain expression for the admittance
and the current noise for a driven nano-capacitor in terms of the Floquet
scattering matrix and derive a non-equilibrium fluctuation-dissipation
relation. As an interplay between the quantum phase coherence and the many-body
correlation, the admittance has peak values whenever the noise power shows a
step as a function of near-by gate voltage.
  Our theory is demonstrated by calculating the admittance and noise of driven
double quantum dots.


title:
Three-Tangle for Rank-3 Mixed States: mixture of
  Greenberger-Horne-Zeilinger, W and flipped W states

abstract:
  Three-tangle for the rank-three mixture composed of
Greenberger-Horne-Zeilinger, W and flipped W states is analytically calculated.
The optimal decompositions in the full range of parameter space are constructed
by making use of the convex-roof extension. We also provide an analytical
technique, which determines whether or not an arbitrary rank-3 state has
vanishing three-tangle. This technique is developed by making use of the Bloch
sphere S^8 of the qutrit system. The Coffman-Kundu-Wootters inequality is
discussed by computing one-tangle and concurrences. It is shown that the
one-tangle is always larger than the sum of squared concurrences and
three-tangle. The physical implication of three-tangle is briefly discussed.


title:
Bulge and Clump Evolution in Hubble Ultra Deep Field Clump Clusters,
  Chains and Spiral Galaxies

abstract:
  Clump clusters and chain galaxies in the Hubble Ultra Deep Field are examined
for bulges in the NICMOS images. Approximately 50% of the clump clusters and
30% of the chains have relatively red and massive clumps that could be young
bulges. Magnitudes and colors are determined for these bulge-like objects and
for the bulges in spiral galaxies, and for all of the prominent star-formation
clumps in these three galaxy types. The colors are fitted to population
evolution models to determine the bulge and clump masses, ages, star-formation
rate decay times, and extinctions. The results indicate that bulge-like objects
in clump cluster and chain galaxies have similar ages and 2 to 5 times larger
masses compared to the star-formation clumps, while the bulges in spirals have
~6 times larger ages and 20 to 30 times larger masses than the clumps. All
systems appear to have an underlying red disk population. The masses of
star-forming clumps are typically in a range from 10^7 to 10^8 Msun; their ages
have a wide range around ~10^2 Myr. Ages and extinctions both decrease with
redshift. Star formation is probably the result of gravitational instabilities
in the disk gas, in which case the large clump mass in the UDF is the result of
a high gas velocity dispersion, 30 km/s or more, combined with a high gas mass
column density, ~100 Msun/pc^2. Because clump clusters and chains dominate disk
galaxies beyond z~1, the observations suggest that these types represent an
early phase in the formation of modern spiral galaxies, when the bulge and
inner disk formed.


title: Berry Phase in a Single Quantum Dot with Spin-Orbit Interaction

abstract:
  Berry phase in a single quantum dot with Rashba spin-orbit coupling is
investigated theoretically. Berry phases as functions of magnetic field
strength, dot size, spin-orbit coupling and photon-spin coupling constants are
evaluated. It is shown that the Berry phase will alter dramatically from 0 to
$2\pi$ as the magnetic field strength increases. The threshold of magnetic
field depends on the dot size and the spin-orbit coupling constant.


title:
Star Formation in Disks: Spiral Arms, Turbulence, and Triggering
  Mechanisms

abstract:
  Star formation is enhanced in spiral arms because of a combination of orbit
crowding, cloud collisions, and gravitational instabilities. The characteristic
mass for the instability is 10^7 Msun in gas and 10^5 Msun in stars, and the
morphology is the familiar beads on a string with 1-2 kpc separation. Similar
instabilities occur in resonance rings and tidal tails. Sequential triggering
from stellar pressure occurs in two ways. For short times and near distances,
it occurs in the bright rims and dense knots that lag behind during cloud
dispersal. For long times, it occurs in swept-up shells and along the periphery
of cleared regions. The first case should be common but difficult to
disentangle from independent star formation in the same cloud. The second case
has a causality condition and a collapse condition and is often easy to
recognize. Turbulent triggering produces a hierarchy of dense cloudy structure
and an associated hierarchy of young star positions. There should also be a
correlation between the duration of star formation and the size of the region
that is analogous to the size-linewidth relation in the gas. The cosmological
context is provided by observations of star formation in high redshift
galaxies. Sequential and turbulent triggering is not yet observable, but
gravitational instabilities are, and they show a scale up from local
instabilities by a factor of ~3 in size and ~100 in mass. This is most easily
explained as the result of an increase in the ISM turbulent speed by a factor
of ~5. In the clumpiest galaxies at high redshift, the clumps are so large that
they should interact with each other and merge in the center, where they form
or contribute to the bulge.


title:
Quasi-metrics, Similarities and Searches: aspects of geometry of protein
  datasets

abstract:
  A quasi-metric is a distance function which satisfies the triangle inequality
but is not symmetric: it can be thought of as an asymmetric metric. The central
result of this thesis, developed in Chapter 3, is that a natural correspondence
exists between similarity measures between biological (nucleotide or protein)
sequences and quasi-metrics.
  Chapter 2 presents basic concepts of the theory of quasi-metric spaces and
introduces a new examples of them: the universal countable rational
quasi-metric space and its bicompletion, the universal bicomplete separable
quasi-metric space. Chapter 4 is dedicated to development of a notion of the
quasi-metric space with Borel probability measure, or pq-space. The main result
of this chapter indicates that `a high dimensional quasi-metric space is close
to being a metric space'.
  Chapter 5 investigates the geometric aspects of the theory of database
similarity search in the context of quasi-metrics. The results about
$pq$-spaces are used to produce novel theoretical bounds on performance of
indexing schemes.
  Finally, the thesis presents some biological applications. Chapter 6
introduces FSIndex, an indexing scheme that significantly accelerates
similarity searches of short protein fragment datasets. Chapter 7 presents the
prototype of the system for discovery of short functional protein motifs called
PFMFind, which relies on FSIndex for similarity searches.


title:
Decoupling and antiresonance in a quantum dot chain with two neighboring
  dots coupled to both leads

abstract:
  Electron transport through a quantum dot chain with two neighboring dots
coupled to both leads is theoretically studied. In such a system, it is found
that only for the even-numbered quantum dot structure with the same-number
quantum dots coupled to each connecting dot, some eigenstates of the quantum
dots decouple from the leads. Namely, all odd eigenstates decouple from the
leads in the absence of magnetic flux, but all even eigenstates will decouple
from the leads when a magnetic flux is introduced. In addition, by adjusting
the magnetic fluxes through any subring, some eigenstates decouple from one
lead but still couple to the other, and then some new antiresonances occur.


title: Patch coalescence as a mechanism for eukaryotic directional sensing

abstract:
  Eukaryotic cells possess a sensible chemical compass allowing them to orient
toward sources of soluble chemicals. The extracellular chemical signal triggers
separation of the cell membrane into two domains populated by different
phospholipid molecules and oriented along the signal anisotropy. We propose a
theory of this polarization process, which is articulated into subsequent
stages of germ nucleation, patch coarsening and merging into a single domain.
We find that the polarization time, $t_\epsilon$, depends on the anisotropy
degree $\epsilon$ through the power law $t_\epsilon\propto \epsilon^{-2}$, and
that in a cell of radius $R$ there should exist a threshold value
$\epsilon_\mathrm{th}\propto R^{-1}$ for the smallest detectable anisotropy.


title: Universal features of cell polarization processes

abstract:
  Cell polarization plays a central role in the development of complex
organisms. It has been recently shown that cell polarization may follow from
the proximity to a phase separation instability in a bistable network of
chemical reactions. An example which has been thoroughly studied is the
formation of signaling domains during eukaryotic chemotaxis. In this case, the
process of domain growth may be described by the use of a constrained
time-dependent Landau-Ginzburg equation, admitting scale-invariant solutions
{\textit{\`a la}} Lifshitz and Slyozov. The constraint results here from a
mechanism of fast cycling of molecules between a cytosolic, inactive state and
a membrane-bound, active state, which dynamically tunes the chemical potential
for membrane binding to a value corresponding to the coexistence of different
phases on the cell membrane. We provide here a universal description of this
process both in the presence and absence of a gradient in the external
activation field. Universal power laws are derived for the time needed for the
cell to polarize in a chemotactic gradient, and for the value of the smallest
detectable gradient. We also describe a concrete realization of our scheme
based on the analysis of available biochemical and biophysical data.


title: Cosmological Perturbations in Models of Coupled Dark Energy

abstract:
  Models in which dark energy interacts with dark matter have been proposed in
the literature to help explain why dark energy should only come to dominate in
recent times. In this paper, we present a dynamical framework to calculate
cosmological perturbations for a general quintessence potential and interaction
term. Our formalism is built upon the powerful phase-space approach often used
to analyse the dynamical attractors in the background. We obtain a set of
coupled differential equations purely in terms of dimensionless, bounded
variables and apply these equations to calculate perturbations in a number of
scenarios. Interestingly, in the presence of dark-sector interactions, we find
that dark energy perturbations do not redshift away at late times, but can
cluster even on small scales. We also clarify the initial conditions for the
perturbations in the dark sector, showing that adiabaticity is no longer
conserved in the presence of dark-sector interactions, even on large scales.
Some issues of instability in the perturbations are also discussed.


title: Charmed Hadron Interactions

abstract:
  We compute the scattering lengths of charmed mesons and charmonia scattering
with light hadrons in full QCD. We use Fermilab formulation for the charm quark
and domain-wall fermions for the light quarks and staggered sea quarks. Four
different light-quark masses are used to extrapolate to the physical point. The
charmed baryon spectrum is also presented.


title: Gravity Mediation of Supersymmetry Breaking with Dynamical Metastability

abstract:
  We argue that the Polonyi problem can be avoided when our
supersymmetry-breaking vacuum is surrounded by many supersymmetric vacua. We
construct a dynamical class of supersymmetry-breaking models to demonstrate our
point. These models naturally predict a small deviation from the standard
big-bang nucleosynthesis.


title: Centrality dependence of v2 in Au + Au at sqrt{s_NN} = 200 GeV

abstract:
  One of the most striking results is the large elliptic flow ($v_2$) at RHIC.
Detailed mass and transverse momentum dependence of elliptic flow are well
described by ideal hydrodynamic calculations for $p_{\mathrm{T}} < $ 1 GeV/c,
and by parton coalescence/recombination picture for $p_{\mathrm{T}} = 2 - 6$
GeV/c. The systematic error on $v_2$ is dominated by so-called "non-flow
effects", which is the correlation not originated from reaction plane. It is
crucial to understand and reduce the systematic error from non-flow effects in
order to understand the underlying collision dynamics. In this paper, we
present the centrality dependence of $v_2$ with respect to the first harmonic
event plane at ZDC-SMD ($v_2$\{ZDC-SMD\}) in Au + Au collisions at
$\sqrt{s_{NN}}$ = 200 GeV. Large rapidity gap ($|\Delta\eta| > 6$) between
midrapidity and the ZDC could enable us to minimize possible non-flow
contributions. We compare the results of $v_2$\{ZDC-SMD\} with $v_2$\{BBC\},
which is measured by event plane determined at $|\eta| = 3.1 - 3.9$. Possible
non-flow contributions in those results will be discussed.


title:
Three-dimensional topological field theory and symplectic algebraic
  geometry I

abstract:
  We study boundary conditions and defects in a three-dimensional topological
sigma-model with a complex symplectic target space X (the Rozansky-Witten
model). We show that boundary conditions correspond to complex Lagrangian
submanifolds in X equipped with complex fibrations. The set of boundary
conditions has the structure of a 2-category; morphisms in this 2-category are
interpreted physically as one-dimensional defect lines separating parts of the
boundary with different boundary conditions. This 2-category is a
categorification of the Z/2-graded derived category of X; it is also related to
categories of matrix factorizations and a categorification of deformation
quantization (quantization of symmetric monoidal categories). In the appendix
we describe a deformation of the B-model and the associated category of branes
by forms of arbitrary even degree.


title:
Sub-mm/mm studies of the molecular gas in the Galactic disk; the TeV
  gamma ray SNR RXJ1713.7-3946 and the W28 high mass star forming region

abstract:
  Interstellar molecular clouds are gamma ray sources through the interactions
with cosmic ray protons followed by production of neutral pions which decay
into gamma rays. We present new NANTEN2 observations of the TeV gamma ray SNR
RXJ1713.7-3946 and the W28 region in the 12CO J=2-1, 4-3 and 7-6 emission
lines. In RXJ1713.7-3946 we confirm that the local molecular gas having
velocities around -10 km/s shows remarkably good spatial correlations with the
SNR. We show that the X ray peaks are well correlated with the molecular gas
over the whole SNR and suggest that the interactions between the SNR and the
molecular gas play an important role in cosmic ray acceleration via several
ways including magnetic field compression. The CO J=4-3 distribution towards
peak C shows a compact and dense cloud core having a size of about 1 pc as well
as a broad wing. The core shows a notable anti-correlation with the Suzaku X
ray image and is also associated with hard gamma rays as observed with HESS.
Based on these findings, we present a picture that peak C is a molecular clump
survived against the impact of the SN blast waves and is surrounded by high
energy electrons emitting the X ray. The TeV gamma ray distribution is, on the
other hand, more extended into the molecular gas, supporting the hadronic
origin of gamma ray production. W28 is one of the most outstanding star forming
regions exhibiting TeV gamma rays as identified through a comparison between
the NANTEN CO dataset and HESS gamma ray sources. In the W28 region, we show
the CO J=2-1 distribution over the whole region as well as the detailed image
of the two TeV gamma ray peaks. One of them show strong CO J=7-6 emission,
suggesting high excitation conditions in this high mass star forming core. A
pursuit for the detailed mechanism to produce gamma rays is in progress.


title: Geodesic Webs and PDE Systems of Euler Equations

abstract:
  We find necessary and sufficient conditions for the foliation defined by
level sets of a function f(x_{1},...,x_{n}) to be totally geodesic in a
torsion-free connection and apply them to find the conditions for d-webs of
hypersurfaces to be geodesic, and in the case of flat connections, for d-webs
(d > n) of hypersurfaces to be hyperplanar webs. These conditions are systems
of generalized Euler equations, and for flat connections we give an explicit
construction of their solutions.


title:
Direct Evidence for Multiferroic Magnetoelectric Coupling in
  0.9BiFeO3-0.1BaTiO3

abstract:
  Magnetic, dielectric and calorimetric studies on 0.9BiFeO3-0.1BaTiO3 indicate
strong magnetoelectric coupling. XRD studies reveal a very remarkable change in
the rhombohedral distortion angle and a significant shift in the atomic
positions at the magnetic Tc due to an isostructural phase transition. The
calculated polarization using Rietveld refined atomic positions scales linearly
with magnetization. Our results provide the first unambiguous evidence for
magnetoelectric coupling of intrinsic multiferroic origin in a BiFeO3 based
system.


title: Quasinormal resonances of near-extremal Kerr-Newman black holes

abstract:
  We study analytically the fundamental resonances of near-extremal, slowly
rotating Kerr-Newman black holes. We find a simple analytic expression for
these black-hole quasinormal frequencies in terms of the black-hole physical
parameters: omega=m Omega-2i pi T(l+1+n), where T and Omega are the temperature
and angular velocity of the black hole. The mode parameters l and m are the
spheroidal harmonic index and the azimuthal harmonic index of a co-rotating
mode, respectively. This analytical formula is valid in the regime Im omega <<
Re omega <<1/M, where M is the black-hole mass.


title:
The effect of dipole-dipole interaction for two atoms with different
  couplings in non-Markovian environment

abstract:
  Using the nonperturbative method, we study the exact entanglement dynamics of
two two-level dipole-dipole interacting atoms coupled to a common non-Markovian
reservoir with different coupling strengths. Besides analyzing the conditions
for the existence of steady state, we find, though the dipole-dipole
interaction could destroy the stationary entanglement, that relatively strong
dipole-dipole interaction does suppress the disentanglement in the initial
period of time. These results are helpful for the practical engineering of the
entanglement in the future.


title:
Calculation of Coefficients of the Optimal Quadrature Formulas in the
  $W_2^{m,m-1}(0,1)$ Space

abstract:
  In this paper problem of construction of optimal quadrature formulas in
$W_2^{(m,m-1)}(0,1)$ space is considered. Here by using Sobolev's algorithm
when $m=1,2$ we find the optimal coefficients of the quadrature formulas of the
form $$ \int\limits_0^1\phi(x)dx\cong
\sum\limits_{\beta=0}^NC_{\beta}\phi(x_{\beta}). $$


title:
Complex extension of potentials and trajectories of poles of the
  S-matrix element in the complex momentum plane

abstract:
  Searching for infrastructure of the quantum mechanical system, we study
trajectories of the s-wave poles of the S-matrix element with respect to a real
phase $\alpha$ in the complex momentum plane for a complex extension of real
potentials by a phase factor $e^{i\alpha}$. This complex extension relates the
pole spectrum of the physical system with a potential to the spectrum of
another system with the potential of the same shape but of opposite sign. There
appear trajectories with the periodicity of $2\pi$, $4\pi$, and $\infty$. The
appearance of non-recurrent behavior of the trajectory for the change of phase
$\Delta \alpha=2\pi$ is clearly related with the existence of resonance poles
for real repulsive potentials. Dynamical changes of trajectory structure are
examined.


title:
Properties of Discrete Analogue of the Differential Operator
  $\frac{d^{2m}}{dx^{2m}}-\frac{d^{2m-2}}{dx^{2m-2}}$

abstract:
  In the paper properties of the discrete analogue $D_m(h\beta)$ of the
differential operator $\frac{d^{2m}}{dx^{2m}}-\frac{d^{2m-2}}{dx^{2m-2}}$ are
studied. It is known, that zeros of differential operator
$\frac{d^{2m}}{dx^{2m}}-\frac{d^{2m-2}}{dx^{2m-2}}$ are functions $e^x$,
$e^{-x}$ and $P_{2m-3}(x)$. It is proved that discrete analogue $D_m(h\beta)$
of this differential operator also have similar properties.


title: Possible superconducting symmetry on doped J1-J2 model

abstract:
  By making use of renormalized mean-field theory, we investigate possible
superconducting symmetries in the ground states of t1-t2-J1-J2 model on square
lattice. The superconducting symmetries of the ground states are determined by
the frustration amplitude t2/t1 and doping concentration. The phase diagram of
this system in frustration-doping plane is given. The order of the phase
transitions among these different superconducting symmetry states of the system
is discussed.


title:
Density of eigenvalues and its perturbation invariance in unitary
  ensembles of random matrices

abstract:
  We generally study the density of eigenvalues in unitary ensembles of random
matrices from the recurrence coefficients with regularly varying conditions for
the orthogonal polynomials. First we calculate directly the moments of the
density. Then, by studying some deformation of the moments, we get a family of
differential equations of first order which the densities satisfy (see Theorem
1.2), and give the densities by solving them. Further, we prove that the
density is invariant after the polynomial perturbation of the weight function
(see Theorem 1.5).


title:
On Gravitational Waves in Spacetimes with a Nonvanishing Cosmological
  Constant

abstract:
  We study the effect of a cosmological constant $\Lambda$ on the propagation
and detection of gravitational waves. To this purpose we investigate the
linearised Einstein's equations with terms up to linear order in $\Lambda$ in a
de Sitter and an anti-de Sitter background spacetime. In this framework the
cosmological term does not induce changes in the polarization states of the
waves, whereas the amplitude gets modified with terms depending on $\Lambda$.
Moreover, if a source emits a periodic waveform, its periodicity as measured by
a distant observer gets modified. These effects are, however, extremely tiny
and thus well below the detectability by some twenty orders of magnitude within
present gravitational wave detectors such as LIGO or future planned ones such
as LISA.


title: Investigation of cold Rb Rydberg atoms in a magneto-optical trap

abstract:
  We present our results on the experiments with cold Rb Rydberg atoms in a
magneto-optical trap (MOT). Characteristic features of our experiment were the
excitation of Rydberg atoms in a small volume within the cold atom cloud and
sorting of the measured signals and spectra over the number of registered
Rydberg atoms. We have measured the effective lifetime of the Rydberg state
37P, as well as its polarizability in a weak electric field. The results are in
good agreement with the theoretical calculations. We have shown that
localization of the small excitation volume around the zero-magnetic-field
point makes possible to increase the spectral resolution and to obtain narrow
microwave resonances in Rydberg atoms without switching off the MOT quadrupole
magnetic field. We have measured the dependence of the amplitude of the
dipole-dipole interaction resonances on the number of Rydberg atoms, which has
a linear character and agrees with the theory for weak dipole-dipole
interaction.


title: Relating Web pages to enable information-gathering tasks

abstract:
  We argue that relationships between Web pages are functions of the user's
intent. We identify a class of Web tasks - information-gathering - that can be
facilitated by a search engine that provides links to pages which are related
to the page the user is currently viewing. We define three kinds of intentional
relationships that correspond to whether the user is a) seeking sources of
information, b) reading pages which provide information, or c) surfing through
pages as part of an extended information-gathering process. We show that these
three relationships can be productively mined using a combination of textual
and link information and provide three scoring mechanisms that correspond to
them: {\em SeekRel}, {\em FactRel} and {\em SurfRel}. These scoring mechanisms
incorporate both textual and link information. We build a set of capacitated
subnetworks - each corresponding to a particular keyword - that mirror the
interconnection structure of the World Wide Web. The scores are computed by
computing flows on these subnetworks. The capacities of the links are derived
from the {\em hub} and {\em authority} values of the nodes they connect,
following the work of Kleinberg (1998) on assigning authority to pages in
hyperlinked environments. We evaluated our scoring mechanism by running
experiments on four data sets taken from the Web. We present user evaluations
of the relevance of the top results returned by our scoring mechanisms and
compare those to the top results returned by Google's Similar Pages feature,
and the {\em Companion} algorithm proposed by Dean and Henzinger (1999).


title: On the cohomology groups of holomorphic Banach bundles

abstract:
  We consider a compact complex manifold $M$, and introduce the notion of two
holomorphic Banach bundles $E,F$ over $M$ being compact perturbations of one
another. Given two such bundles we show that if the cohomology groups
$H^q(M,E)$ are finite dimensional then so are the cohomology groups $H^q(M,F)$;
as well as a more precise result in the same spirit.


abstract:
  We argue that Solar system tests do not rule out 1/R gravity at least due to
the reason addressed in Phys. Rev. D 74 (2006) 121501 [astro-ph/0610483] (ref.
[1]) and subsequent published papers.
  Ref. [1] has not only modified the Einstein-Hilbert action but also has
changed the boundary conditions since they altered the equations of motion. In
Einstein-Hilbert action equations are second order, so the fall off of the
fields suffices to single out a unique solution. In 1/R gravity the equations
are fourth order, so we should impose additional boundary conditions. Perhaps
the boundary condition we must impose is that the abrupt change in the second
derivative of the metric near the surface of the Sun remains intact by adding
`1/R' corrections to the equations of motion. The solution of 1/R gravity with
this boundary condition remains consistent with the solar system tests.
  Ref. [1] assumes that as soon as they perturbatively modified the equations
then the Ricci scalar becomes smooth on the surface of the Sun. This assumption
is simply wrong because the boundary conditions and equations of motions are
two different entities.