title:
Hall effect and magnetoresistance in the normal state of the
  superconductor LaO$_{0.9}$F$_{0.1-x}$FeAs

abstract:
  By using a two-step method, we successfully synthesized the iron based new
superconductor LaO$_{0.9}$F$_{0.1-x}$FeAs. The Hall effect and
magnetoresistance were measured in wide temperature region. A negative Hall
coefficient R_H has been found implying a dominant conduction by electron-like
charge carriers in this material. The charge carrier density determined at 100K
is about 9.8E20 cm-3, which is close to the cuprate superconductors. It is
further found that the magnetoresistance does not follow the Kohler's law.
Meanwhile, the Hall coefficient, the resistivity at 0T, and magnetoresistance
all have an anomalous property at about 240K, which may be induced by the
multi-band effect or by some exotic scattering mechanism.


title:
Joint effects of nutrients and contaminants on the dynamics of a food
  chain in marine ecosystems

abstract:
  We analyze the joint effect of contaminants and nutrient loading on
population dynamics of marine food chains by means of bifurcation analysis.
Contaminant toxicity is assumed to alter mortality of some species with a
sigmoidal dose-response relationship. A generic effect of pollutants is to
delay transitions to complex dynamical states towards higher nutrient load
values, but more counterintuitive consequences arising from indirect effects
are described. In particular, the top predator seems to be the species more
affected by pollutants, even when contaminant is toxic only to lower trophic
levels.


title: Polling systems with parameter regeneration, the general case

abstract:
  We consider a polling model with multiple stations, each with Poisson
arrivals and a queue of infinite capacity. The service regime is exhaustive and
there is Jacksonian feedback of served customers. What is new here is that when
the server comes to a station it chooses the service rate and the feedback
parameters at random; these remain valid during the whole stay of the server at
that station. We give criteria for recurrence, transience and existence of the
$s$th moment of the return time to the empty state for this model. This paper
generalizes the model, when only two stations accept arriving jobs, which was
considered in [Ann. Appl. Probab. 17 (2007) 1447--1473]. Our results are stated
in terms of Lyapunov exponents for random matrices. From the recurrence
criteria it can be seen that the polling model with parameter regeneration can
exhibit the unusual phenomenon of null recurrence over a thick region of
parameter space.


title: The tiered Aubry set for autonomous Lagrangian functions

abstract:
  If L is a Tonelli Lagrangian defined on the tangent bundle of a compact and
connected manifold whose dimension is at least 2, we associate to L the tiered
Aubry set and the tiered Mane set (defined in the article). We prove that the
tiered Mane set is closed, connected, chain transitive and that if L is generic
in the Mane sense, the tiered Mane set has no interior. Then, we give an
example of such an explicit generic Tonelli Lagrangian function and an example
proving that when M is the torus, the closure of the tiered Aubry set and the
closure of the union of the K.A.M. tori may be different.


title:
Thermal and Quantum Fluctuations Induced Additional Gap in
  Single-particle Spectrum of d-p model

abstract:
  The possibility of thermal and quantum fluctuations induced attractive
interaction leading to a pairing gap \Delta_tq in the single-particle spectrum
of d-p model in the limit of a large N of fermion flavor is investigated
analytically. This is an anomalous pairing gap in addition to the one with
d-wave symmetry originating from partially screened, inter-site coulomb
interaction. The motivation was to search for a hierarchy of multiple many-body
interaction scales in high-Tc superconductor as suggested by recent
experimental findings. The pairing gap anisotropy stems from more than one
sources, namely, nearest neighbour hoppings and the p-d hybridization but not
the coupling of the effective interaction. The temperature at which \Delta_tq
vanishes may be driven to zero by using a tuning parameter to have access to
quantum criticality only when N >> 1. For the physical case N = 2, the usual
coherent quasi-particle feature surfaces in the spectral weight everywhere in
the momentum space below the pairing gap \Delta_tq. Thus it appears that the
reduction in spin degeneracy has the effect of masking quantum criticality.


title:
Improved orbital solution and masses for the very low-mass multiple
  system LHS 1070

abstract:
  We present a refined orbital solution for the components A, B, and C of the
nearby late-M type multiple system LHS 1070. By combining astrometric
datapoints from NACO/VLT, CIAO/SUBARU, and PUEO/CFHT, as well as a radial
velocity measurement from the newly commissioned near infrared high-resolution
spectrograph CRIRES/VLT, we achieve a very precise orbital solution for the B
and C components and a first realistic constraint on the much longer orbit of
the A-BC system. Both orbits appear to be co-planar. Masses for the B and C
components calculated from the new orbital solution (M_(B+C) = 0.157 +/- 0.009
M_sun) are in excellent agreement with theoretical models, but do not match
empirical mass-luminosity tracks. The preliminary orbit of the A-BC system
reveals no mass excess for the A component, giving no indication for a
previously proposed fourth (D) component in LHS 1070.


title:
Non-proper helicoid-like limits of closed minimal surfaces in
  3-manifolds

abstract:
  We show that there exists a metric with positive scalar curvature on S2xS1
and a sequence of embedded minimal cylinders that converges to a minimal
lamination that, in a neighborhood of a strictly stable 2-sphere, is smooth
except at two helicoid-like singularities on the 2-sphere. The construction is
inspired by a recent example by D. Hoffman and B. White.


title: The Theory of Fallible Probability and The Dynamics of Degrees of Belief

abstract:
  This monograph is an account of the theory of fallible probability and of the
dynamics of degrees of belief. It discusses the first order subjective theory
in which first order degrees of belief are expressed by subjective
probabilities and are updated by conditionalization (Bayes, 1764; Ramsey,
1926), gives an improved exposition of the greater part of the author's theory
of Probability Dynamics (Nathan, 2006) which should replace the so-called
Probability Kinematics (Jeffrey, 1965), resolves the problem of New Explanation
of Old Evidence (Jeffrey, 1995), provides a Theory of Confirmation, and refutes
the Principle of Reflection (Van Fraassen, 1984).


title: Photons from Dark Matter in a (non-Universal) Extra Dimension model

abstract:
  We study the multi-wavelength signal induced by pairs annihilations at the
Galactic center (GC) of a recently proposed dark matter (DM) candidate. The
weakly interacting massive particle (WIMP) candidate, named A_, is the first
Kaluza-Klein mode of a five dimensional Abelian gauge boson. Electroweak
precision tests and the DM cosmological bound constrain its mass and pair
annihilation rate in small ranges, leading to precise predictions of indirect
signals from what concerns the particle physics side. The related
multi-wavelength emission is expected to be faint, unless a significant
enhancement of the DM density is present at the GC. We find that in this case,
and depending on few additional assumptions, the next generation of gamma-ray
and wide-field radio observations can test the model, possibly even with the
detection of the induced monochromatic gamma-ray emission.


title: Network Coding for Distributed Storage Systems

abstract:
  Distributed storage systems provide reliable access to data through
redundancy spread over individually unreliable nodes. Application scenarios
include data centers, peer-to-peer storage systems, and storage in wireless
networks. Storing data using an erasure code, in fragments spread across nodes,
requires less redundancy than simple replication for the same level of
reliability. However, since fragments must be periodically replaced as nodes
fail, a key question is how to generate encoded fragments in a distributed way
while transferring as little data as possible across the network.
  For an erasure coded system, a common practice to repair from a node failure
is for a new node to download subsets of data stored at a number of surviving
nodes, reconstruct a lost coded block using the downloaded data, and store it
at the new node. We show that this procedure is sub-optimal. We introduce the
notion of regenerating codes, which allow a new node to download
\emph{functions} of the stored data from the surviving nodes. We show that
regenerating codes can significantly reduce the repair bandwidth. Further, we
show that there is a fundamental tradeoff between storage and repair bandwidth
which we theoretically characterize using flow arguments on an appropriately
constructed graph. By invoking constructive results in network coding, we
introduce regenerating codes that can achieve any point in this optimal
tradeoff.


title: Constrained Willmore Tori in the 4--Sphere

abstract:
  We prove that a constrained Willmore immersion of a 2-torus into the
conformal 4-sphere is either of "finite type", that is, has a spectral curve of
finite genus, or is of "holomorphic type" which means that it is super
conformal or Euclidean minimal with planar ends. This implies that all
constrained Willmore tori in the 4-sphere can be constructed rather explicitly
by methods of complex algebraic geometry. The proof uses quaternionic
holomorphic geometry in combination with integrable systems methods similar to
those of Hitchin's approach to the study of harmonic tori in the 3-sphere.


title:
Weighing the Black Holes in z~2 Submillimeter-Emitting Galaxies Hosting
  Active Galactic Nuclei

abstract:
  We place direct observational constraints on the black-hole masses of the
cosmologically important z~2 submillimeter-emitting galaxy (SMG; f850>4mJy)
population, and use measured host-galaxy masses to explore their evolutionary
status. We employ the well-established virial black-hole mass estimator to
'weigh' the black holes of a sample of z~2 SMGs with broad Halpha or Hbeta
emission. The average black-hole mass and Eddington ratio (eta) of the
lower-luminosity broad-line SMGs (L_X~10^44 erg/s} are log(M_BH/M_sol)~8.0 and
eta~0.2, respectively. These lower-luminosity broad-line SMGs lie in the same
location of the L_X-L_FIR plane as more typical SMGs hosting X-ray obscured AGN
and may be intrinsically similar systems, but orientated so that the rest-frame
optical nucleus is visible. Under this hypothesis, we conclude that SMGs host
black holes with log(M_BH/M_odot)~7.8; we find supporting evidence from
observations of local ULIRGs. Combining these black-hole mass constraints with
measured host-galaxy masses, we find that the black holes in SMGs are >3 times
smaller than those found in comparably massive normal galaxies in the local
Universe, albeit with considerable uncertainty, and >10 times smaller than
those predicted for z~2 luminous quasars and radio galaxies. These results
imply that the growth of the black hole lags that of the host galaxy in SMGs,
in stark contrast with that previously suggested for radio galaxies and
luminous quasars at z~2. On the basis of current host-galaxy mass constraints,
we show that SMGs and their descendants cannot lie significantly above the
locally defined M_BH-M_GAL relationship. We argue that the black holes in the
z~0 descendents of SMGs will have log(M_BH/M_odot)~8.6, indicating that they
only need to grow by a factor of ~6 by the present day (ABRIDGED).


title:
An Averaging Principle for Combined Interaction Graphs. Part I:
  Connectivity and Applications to Genetic Switches

abstract:
  Time-continuous dynamical systems defined on graphs are often used to model
complex systems with many interacting components in a non-spatial context. In
the reverse sense attaching meaningful dynamics to given 'interaction diagrams'
is a central bottleneck problem in many application areas, especially in cell
biology where various such diagrams with different conventions describing
molecular regulation are presently in use. In most situations these diagrams
can only be interpreted by the use of both discrete and continuous variables
during the modelling process, corresponding to both deterministic and
stochastic hybrid dynamics. The conventions in genetics are well-known, and
therefore we use this field for illustration purposes. In [25] and [26] the
authors showed that with the help of a multi-scale analysis stochastic systems
with both continuous variables and finite state spaces can be approximated by
dynamical systems whose leading order time evolution is given by a combination
of ordinary differential equations (ODEs) and Markov chains. The leading order
term in these dynamical systems is called average dynamics and turns out to be
an adequate concept to analyse a class of simplified hybrid systems. Once the
dynamics is defifined the mutual interaction of both ODEs and Markov chains can
be analysed through the (reverse) introduction of the so called Interaction
Graph, a concept originally invented for time-continuous dynamical systems, see
[5]. Here we transfer this graph concept to the average dynamics, which itself
is introduced as an heuristic tool to construct models of reaction or contact
networks. The graphical concepts introduced form the basis for any subsequent
study of the qualitative properties of hybrid models in terms of connectivity
and (feedback) loop formation.


title:
Reliable Identification of Compton-thick Quasars at z~2: Spitzer Mid-IR
  spectroscopy of HDF-oMD49

abstract:
  Many models that seek to explain the origin of the unresolved X-ray
background predict that Compton-thick Active Galactic Nuclei (AGNs) are
ubiquitious at high redshift. However, few distant Compton-thick AGNs have been
reliably identified to date. Here we present Spitzer-IRS spectroscopy and
3.6-70um photometry of a z=2.2 optically identified AGN (HDF-oMD49) that is
formally undetected in the 2Ms Chandra Deep Field-North (CDF-N) survey. The
Spitzer-IRS spectrum and spectral energy distribution of this object is AGN
dominated, and a comparison of the energetics at X-ray wavelengths to those
derived from mid-infrared (mid-IR) and optical spectroscopy shows that the AGN
is intrinsically luminous (L_X~3x10^44 erg/s) but heavily absorbed by
Compton-thick material (N_H>>10^24 cm^{-2}); i.e., this object is a
Compton-thick quasar. Adopting the same approach that we applied to HDF-oMD49,
we found a further six objects at z~2-2.5 in the literature that are also X-ray
weak/undetected but have evidence for AGN activity from optical and/or mid-IR
spectroscopy, and show that all of these sources are also Compton-thick quasars
with L_X>10^44 erg/s. On the basis of the definition of Daddi etal. (2007),
these Compton-thick quasars would be classified as mid-IR excess galaxies, and
our study provides the first spectroscopic confirmation of Compton-thick AGN
activity in a subsample of these z~2 mid-IR bright galaxies. Using the four
objects that lie in the CDF-N field, we estimate the space-density of
Compton-thick quasars [Phi~(0.7-2.5)x10^-5 Mpc^-3 for L_X>10^44 erg/s objects
at z~2-2.5] and show that Compton-thick accretion is as ubiquitious as
unobscured accretion in the distant Universe.


title:
Magnetic dynamo C-flows in Riemannian manifold as generalized Arnold's
  map

abstract:
  It is shown that C-flows in Riemannian three-dimensional compact manifold can
be naturally considered as generalized dynamo Arnold's metric in compact
manifolds, the so-called cat map dynamo. The generalized solution of
self-induction equation in the background of this metric shows that one is
allowed to consider stretching along both directions of the flow, instead of
compressed in one direction and stretched in the other such as in Arnold's
dynamo. Though this solution can be considered as unrealistic,at least for
incompressible flows, there is another generalized solution which considers
distinct stretch and compression intensities along distinct directions.
Curvature tensor components are computed by making use of calculus of
differential forms.


title:
Doping dependence of the upper critical field in La_{2-x}Sr_xCuO_4 from
  specific heat

abstract:
  The low-temperature specific heat of La_{2-x}Sr_xCuO_4 (LSCO) single crystals
in magnetic field H up to 12 T has been examined over a wide range of doping
(0.063=< p =<0.238). From this we have mapped the upper critical field H_{c2}
of LSCO across the entire superconducting diagram. It is found that the H_{c2}
shows a doping dependence similar to that of the critical temperature T_c. We
have discussed the implications of the result and proposed that there may be an
effective superconducting energy scale responsible for the H_{c2} behavior in
the underdoped region.


title:
Radio-loud and radio-quiet quasars: one population, different epochs of
  observation

abstract:
  I bring together evidence for the rapidity with which quasars' radio
synchrotron lobe emission fades and for the intermittency with which jet plasma
is ejected from individual quasars and radio galaxies and affirm the picture
presented by Nipoti et al (2005) that the radio-loudness of quasars is a
function of the epoch at which they are observed. I briefly illustrate this
account with examples of successive episodes of jet activity where the axis
along which jet plasma is launched appears to have precessed. A new model for
the weak core radio emission from radio-quiet quasars, that is not any kind of
jet ejecta, is also briefly described.


title: Metric properties of Outer Space

abstract:
  We define metrics on Culler-Vogtmann space, which are an analogue of the
Teichmuller metric and are constructed using stretching factors. In fact the
metrics we study are related, one being a symmetrised version of the other. We
investigate the basic properties of these metrics, showing the advantages and
pathologies of both choices. We show how to compute stretching factors between
marked metric graphs in an easy way and we discuss the behaviour of stretching
factors under iterations of automorphisms. We study metric properties of
folding paths, showing that they are geodesic for the non-symmetric metric and,
if they do not enter the thin part of Outer space, quasi-geodesic for the
symmetric metric.


title:
Model building by Coset space dimensional reduction scheme using
  ten-dimensional coset spaces

abstract:
  We investigate the gauge-Higgs unification models within the scheme of the
coset space dimensional reduction, beginning with a gauge theory in a
fourteen-dimensional spacetime where extra-dimensional space has the structure
of a ten-dimensional compact coset space. We found seventeen phenomenologically
acceptable models through an exhaustive search for the candidates of the coset
spaces, the gauge group in fourteen dimension, and fermion representation. Of
the seventeen, ten models led to $\mathrm{SO}(10) (\times \mathrm{U}(1))$
GUT-like models after dimensional reduction, three models led to
$\mathrm{SU}(5) \times \mathrm{U}(1)$ GUT-like models, and four to
$\mathrm{SU}(3) \times \mathrm{SU}(2) \times \mathrm{U}(1) \times
\mathrm{U}(1)$ Standard-Model-like models. The combinations of the coset space,
the gauge group in the fourteen-dimensional spacetime, and the representation
of the fermion contents of such models are listed.


title:
SS433: Observation of the circumbinary disc and extraction of the system
  mass

abstract:
  The so-called "stationary" H-alpha line of SS433 is shown to consist of three
components. A broad component is identified as emitted in that wind from the
accretion disc which grows in speed with elevation above the plane of the disc.
There are two narrow components, one permanently redshifted and the other
permanently to the blue. These are remarkably steady in wavelength and must be
emitted from a circumbinary ring, orbiting the centre of mass of the system
rather than orbiting either the compact object or its companion: perhaps the
inner rim of an excretion disc. The orbiting speed (approximately 200 km/s) of
this ring material strongly favours a large mass for the enclosed system
(around 40 solar masses), a large mass ratio for SS433, a mass for the compact
object plus accretion disc of ~16 solar masses and hence the identity of the
compact object as a rather massive stellar black hole.


title:
Multiplicity, mean $p_T$, $p_T$-spectra and elliptic flow of identified
  particles in Pb+Pb collisions at LHC

abstract:
  Israel-Stewart's causal theory of dissipative hydrodynamics, with the ADS/CFT
lower limit of shear viscosity to entropy ratio ($\eta/s$=0.08), give
consistent description of a number of experimental observables in Au+Au
collisions at RHIC (c.m. energy $\sqrt{s}$=200 GeV) \cite{Chaudhuri:2008sj}.
Assuming that in Pb+Pb collisions at LHC (c.m. energy $\sqrt{s}$=5.5 TeV),
except for the initial temperature, other parameters of the fluid remain
unchanged, we have predicted for the centrality dependence of multiplicity,
mean $p_T$, $p_T$-spectra, elliptic flow. The central temperature of the fluid
is adjusted to $T_i$=421 MeV such that in a Pb+Pb collision, with participant
number $N_{part}$=350, average charge particle multiplicity is $\sim$ 900 and
is consistent with the experimental trend observed at lower energies. Compare
to Au+Au collisions at RHIC, in Pb+Pb collisions at LHC, on the average,
particle multiplicity increases by a factor of $\sim$1.6, the mean $p_T$ is
increased by $\sim$10% only. The elliptic flow on the other hand decreases by
$\sim$15%.


title: Superconductivity in the Mo_2Re_3B compound

abstract:
  We report on the synthesis and on basic superconducting properties of a
completely new Mo_2Re_3B ternary boride. The crystal structure of the Mo_2Re_3B
compound is characterised by Pmmm space group and the cell parameters: a=11.626
A, b=8.465 A and c=8.026 A. The critical temperature is Tc=8.5 K, whereas the
lower and the upper-critical fields at zero temperature are equal to
Hc1(0)=19.2 mT and to Hc2(0)=3.7 T, respectively. The corresponding
Ginzburg-Landau parameter is equal to k=16.5 and the superconducting gap is
estimated to be 2delta/kTc=3.2.


title: Arithmetic of a fake projective plane and related elliptic surfaces

abstract:
  The purpose of the present paper is to explain the fake projective plane
constructed by J.H. Keum from the point of view of arithmetic ball quotients.
Beside the ball quotient associated with the fake projective plane, we also
analize two further naturally related ball quotients whose minimal
desingularizations lead to two elliptic surfaces, one already considered by
J.H. Keum as well as the one constructed by M.N. Ishida in terms of p-adic
uniformization.


title: Two parton shower background for associate W Higgs production

abstract:
  The estimates of the background for the associate W Higgs production, which
stems from the two parton shower production. It is about 1 - 2.5 times larger
than the signal. However, this background does not depend on the rapidity
difference between the W and the $b \bar{b}$ pair, while the signal peaks when
the rapidity difference is zero. The detailed calculations for the enhanced
diagrams' contribution to this process, are presented, and it is shown that the
overlapping singularities, being important theoretically, lead to a negligible
contribution for the LHC range of energies


title:
Domain Dynamics in Piezoresponse Force Microscopy: Quantitative
  Deconvolution and Hysteresis Loop Fine Structure

abstract:
  Domain dynamics in the Piezoresponse Force Spectroscopy (PFS) experiment is
studied using the combination of local hysteresis loop acquisition with
simultaneous domain imaging. The analytical theory for PFS signal from domain
of arbitrary cross-section is developed and used for the analysis of
experimental data on Pb(Zr,Ti)O3 polycrystalline films. The results suggest
formation of oblate domain at early stage of the domain nucleation and growth,
consistent with efficient screening of depolarization field within the
material. The fine structure of the hysteresis loop is shown to be related to
the observed jumps in the domain geometry during domain wall propagation
(nanoscale Barkhausen jumps), indicative of strong domain-defect interactions.


title: Space-time extensions II

abstract:
  The global extendibility of smooth causal geodesically incomplete spacetimes
is investigated. Denote by $\gamma$ one of the incomplete non-extendible causal
geodesics of a causal geodesically incomplete spacetime $(M,g_{ab})$. First, it
is shown that it is always possible to select a synchronised family of causal
geodesics $\Gamma$ and an open neighbourhood $\mathcal{U}$ of a final segment
of $\gamma$ in $M$ such that $\mathcal{U}$ is comprised by members of $\Gamma$,
and suitable local coordinates can be defined everywhere on $\mathcal{U}$
provided that $\gamma$ does not terminate either on a tidal force tensor
singularity or on a topological singularity. It is also shown that if, in
addition, the spacetime, $(M,g_{ab})$, is globally hyperbolic, and the
components of the curvature tensor, and its covariant derivatives up to order
$k-1$ are bounded on $\mathcal{U}$, and also the line integrals of the
components of the $k^{th}$-order covariant derivatives are finite along the
members of $\Gamma$---where all the components are meant to be registered with
respect to a synchronised frame field on $\mathcal{U}$---then there exists a
$C^{k-}$ extension $\Phi: (M,g_{ab}) \rightarrow
(\widehat{M},\widehat{g}_{ab})$ so that for each $\bar\gamma\in\Gamma$, which
is inextendible in $(M,g_{ab})$, the image, $\Phi\circ\bar\gamma$, is
extendible in $(\widehat{M},\widehat{g}_{ab})$. Finally, it is also proved that
whenever $\gamma$ does terminate on a topological singularity $(M,g_{ab})$
cannot be generic.


title: Coulomb excitation of $^{68}$Ni at safe energies

abstract:
  The $B(E2;0^+\to2^+)$ value in $^{68}$Ni has been measured using Coulomb
excitation at safe energies. The $^{68}$Ni radioactive beam was
post-accelerated at the ISOLDE facility (CERN) to 2.9 MeV/u. The emitted
$\gamma$ rays were detected by the MINIBALL detector array. A kinematic
particle reconstruction was performed in order to increase the measured c.m.
angular range of the excitation cross section. The obtained value of
2.8$^{+1.2}_{-1.0}$ 10$^2$ e$^2$fm$^4$ is in good agreement with the value
measured at intermediate energy Coulomb excitation, confirming the low
$0^+\to2^+$ transition probability.


title: Alternating gradient focusing and deceleration of large molecules

abstract:
  We have focused and decelerated benzonitrile (C$_7$H$_5$N) molecules from a
molecular beam, using an array of time-varying inhomogeneous electric fields in
alternating gradient configuration. Benzonitrile is prototypical for large
asymmetric top molecules that exhibit rich rotational structure and a high
density of states. At the rotational temperature of 3.5 K in the pulsed
molecular beam, many rotational states are populated. Benzonitrile molecules in
their absolute ground state are decelerated from 320 m/s to 289 m/s, and
similar changes in velocity are obtained for excited rotational states. All
measurements agree well with the outcome of trajectory calculations. These
experiments demonstrate that such large polyatomic molecules are amenable to
the powerful method of Stark deceleration.


title:
Accurate near-threshold model for ultracold KRb dimers from interisotope
  Feshbach spectroscopy

abstract:
  We investigate magnetic Feshbach resonances in two different ultracold K-Rb
mixtures. Information on the K(39)-Rb(87) isotopic pair is combined with novel
and pre-existing observations of resonance patterns for K(40)-Rb(87).
Interisotope resonance spectroscopy improves significantly our near-threshold
model for scattering and bound-state calculations. Our analysis determines the
number of bound states in singlet/triplet potentials and establishes precisely
near threshold parameters for all K-Rb pairs of interest for experiments with
both atoms and molecules. In addition, the model verifies the validity of the
Born-Oppenheimer approximation at the present level of accuracy.


title:
The behavior of magnetic ordering and the KOndo effect in the alloys,
  Ce2Rh(1-x)Co(x)Si3: Evidence from bulk studies for Fermi-surface change
  during magnetic ordering - QCP transformation and applicability of SDW pictur

abstract:
  The results of magnetic susceptibility, electrical resistivity (rho), and
heat capacity measurements as a function of temperature are reported for the
alloys, Ce2Rh(1-x)Co(x)Si3, crystallizing in an AlB2-derived hexagonal
strcture. Ce2RhSi3 exhibits antiferromagnetic ordering at 7 K. The Neel
temperature decreases gradually with the increase in Co concentration. For x
greater than 0.6, no magnetic ordering is observed down to 0.5 K.
Interestingly, the x= 0.6 alloy exhibits signatutes of non-Fermi liquid
behavior, while the Co end member is a Fermi liquid. Thus, a transformation of
magnetic ordering state to non-magnetism via non-Fermiliquid state by
isoelectronic chemical doping is evident in this solid solution. The electrical
resistivity data for x= 0.2 and 0.3 alloys show an upturn at respective Neel
temperatures, establishing the formation of a magnetism-induced pseudo-gap for
these intermediate compositions alone as though there is a gradual Fermi
surface transformation as the quantum critical point is approached.


title: Aggregating and Deploying Network Access Control Policies

abstract:
  The existence of errors or inconsistencies in the configuration of security
components, such as filtering routers and/or firewalls, may lead to weak access
control policies -- potentially easy to be evaded by unauthorized parties. We
present in this paper a proposal to create, manage, and deploy consistent
policies in those components in an efficient way. To do so, we combine two main
approaches. The first approach is the use of an aggregation mechanism that
yields consistent configurations or signals inconsistencies. Through this
mechanism we can fold existing policies of a given system and create a
consistent and global set of access control rules -- easy to maintain and
manage by using a single syntax. The second approach is the use of a refinement
mechanism that guarantees the proper deployment of such a global set of rules
into the system, yet free of inconsistencies.


title: Blazar sequence - an artefact of Doppler boosting

abstract:
  The blazar sequence is a scenario in which the bolometric luminosity of the
blazar governs the appearance of its spectral energy distribution. The most
prominent result is the significant negative correlation between the
synchrotron peak frequencies and the synchrotron peak luminosities of the
blazar population. Observational studies of the blazar sequence have, in
general, neglected the effect of Doppler boosting. We study the dependence of
both the synchrotron peak frequency and luminosity with Doppler-corrected
quantities. We determine the spectral energy distributions of 135 radio-bright
AGN and find the best-fit parabolic function for the distribution to quantify
their synchrotron emission. The corresponding measurements of synchrotron peak
luminosities and frequencies are Doppler-corrected with a new set of Doppler
factors calculated from variability data. The relevant correlations for the
blazar sequence are determined for these intrinsic quantities. The Doppler
factor depends strongly on the synchrotron peak frequency, the lower energy
sources being more boosted. Applying the Doppler correction to the peak
frequencies and luminosities annuls the negative correlation between the two
quantities, which becomes positive. For BL Lacertae objects, the positive
correlation is particularly strong. The blazar sequence, when defined as the
anticorrelation between the peak frequency and luminosity of the synchrotron
component of the spectral energy distribution, disappears when the intrinsic,
Doppler-corrected values are used. It is an observational phenomenon created by
variable Doppler boosting across the synchrotron peak frequency range.


title: Giant room temperature piezoresistance in a metal/silicon hybrid

abstract:
  Metal/semiconductor hybrids are artificially created structures presenting
novel properties not exhibited by either of the component materials alone. Here
we present a giant piezoresistance effect in a hybrid formed from silicon and
aluminum. The maximum piezoresistive gage factor (GF) of 843, measured at room
temperature, compares with a GF of -93 measured in the bulk homogeneous
silicon. This piezoresistance boost is not due to the silicon/aluminum
interface, but results from a stress induced anisotropy in the silicon
conductivity that acts to switch current away from the highly conductive
aluminum for uniaxial tensile strains. Its magnitude is shown, via the
calculation of hybrid resistivity weighting functions, to depend only on the
geometrical arrangement of the component parts of the hybrid.


title: Strong lensing statistics and the power spectrum normalisation

abstract:
  We use semi-analytic modelling of the galaxy-cluster population and its
strong lensing efficiency to explore how the expected abundance of large
gravitational arcs on the sky depends on $\sigma_8$. Our models take all
effects into account that have been shown to affect strong cluster lensing
substantially, in particular cluster asymmetry, substructure, merging, and
variations in the central density concentrations. We show that the optical
depth for long and thin arcs increases by approximately one order of magnitude
when $\sigma_8$ increases from 0.7 to 0.9, owing to a constructive combination
of several effects. Models with high $\sigma_8$ are also several orders of
magnitude more efficient in producing arcs at intermediate and high redshifts.
Finally, we use realistic source number counts to quantitatively predict the
total number of arcs brighter than several magnitude limits in the R and I
bands. We confirm that, while $\sigma_8\sim0.9$ may come close to the known
abundance of arcs, even $\sigma_8\sim0.8$ falls short by almost an order of
magnitude in reproducing known counts. We conclude that, should
$\sigma_8\sim0.8$ be confirmed, we would fail to understand the strong-lensing
efficiency of the galaxy cluster population, and in particular the abundance of
arcs in high-redshift clusters. We argue that early-dark energy or non-Gaussian
density fluctuations may indicate one way out of this problem.


title: Decoding the geometry of conformal field theories

abstract:
  To certain geometries, string theory associates conformal field theories. We
discuss techniques to perform the reverse procedure: To recover geometrical
data from abstractly defined conformal field theories. This is done by
introducing appropriate notions of limits of conformal field theories and their
degenerations, and by applying techniques from noncommutative geometry.
  This note is a summary of our work hep-th/0308143 , aimed to be less
technical than the original paper, along with some new calculations confirming
our interpretation of the rescaled limiting zero mode of the Virasoro field.


title:
The defining ideals of conjugacy classes of nilpotent matrices and a
  conjecture of Weyman

abstract:
  Tanisaki introduced generating sets for the defining ideals of the schematic
intersections of the closure of conjugacy classes of nilpotent matrices with
the set of diagonal matrices. These ideals are naturally labeled by integer
partitions. Given such a partition $\lambda$, we define several methods to
produce a reduced generating set for the associated ideal $I_{\lambda}$. For
particular shapes we find nice generating sets. By comparing our sets with some
generating sets of $I_{\lambda}$ arising from a work of Weyman, we find a
counterexample to a related conjecture of Weyman.


title: First Evidence of New Physics in b <--> s Transitions

abstract:
  We combine all the available experimental information on Bs mixing, including
the very recent tagged analyses of Bs to J/Psi phi by the CDF and D0
collaborations. We find that the phase of the Bs mixing amplitude deviates more
than 3 sigma from the Standard Model prediction. While no single measurement
has a 3 sigma significance yet, all the constraints show a remarkable agreement
with the combined result. This is a first evidence of physics beyond the
Standard Model. This result disfavours New Physics models with Minimal Flavour
Violation with the same significance.


title: Slow decay of magnetic fields in open Friedmann universes

abstract:
  We describe how magnetic fields in Friedmann universes can experience
superadiabatic growth without departing from conventional electromagnetism. The
reason is the relativistic coupling between vector fields and spacetime
geometry, which slows down the decay of large-scale magnetic fields in open
universes, compared to that seen in perfectly flat models. The result is a
large relative gain in magnetic strength during the pre-galactic era that can
lead to astrophysically interesting B-fields, even if our universe is only
marginally open today.


title: Towards an Optimal Separation of Space and Length in Resolution

abstract:
  Most state-of-the-art satisfiability algorithms today are variants of the
DPLL procedure augmented with clause learning. The main bottleneck for such
algorithms, other than the obvious one of time, is the amount of memory used.
In the field of proof complexity, the resources of time and memory correspond
to the length and space of resolution proofs. There has been a long line of
research trying to understand these proof complexity measures, but while strong
results have been proven on length our understanding of space is still quite
poor. For instance, it remains open whether the fact that a formula is provable
in short length implies that it is also provable in small space or whether on
the contrary these measures are unrelated in the sense that short proofs can be
arbitrarily complex with respect to space.
  In this paper, we present some evidence that the true answer should be that
the latter case holds. We do this by proving a tight bound of Theta(sqrt(n)) on
the space needed for so-called pebbling contradictions over pyramid graphs of
size n. This yields the first polynomial lower bound on space that is not a
consequence of a corresponding lower bound on width, another well-studied
measure in resolution, as well as an improvement of the weak separation in
(Nordstrom 2006) of space and width from logarithmic to polynomial.
  Also, continuing the line of research initiated by (Ben-Sasson 2002) into
trade-offs between different proof complexity measures, we present a simplified
proof of the recent length-space trade-off result in (Hertel and Pitassi 2007),
and show how our ideas can be used to prove a couple of other exponential
trade-offs in resolution.


title:
Radiative corrections to the cross section of $e^-+p\to \nu+n$ and the
  crossed processes

abstract:
  Born cross section and the radiative corrections to its lowest order are
considered in the frame work of QED with structureless nucleons including the
emission of virtual and real photons. Result is generalized to take into
account radiative corrections in higher orders of perturbation theory in the
leading and next-to leading logarithmic approximation. Crossing processes are
considered in the leading approximation.


title: The Cosmological Constant Problem and Inflation in the String Landscape

abstract:
  An earlier paper points out that a quantum treatment of the string landscape
is necessary. It suggests that the wavefunction of the universe is mobile in
the landscape until the universe reaches a meta-stable site with its
cosmological constant $\Lambda_0$ smaller than the critical value $\Lambda_c$,
where $\Lambda_c$ is estimated to be exponentially small compared to the Planck
scale. Since this site has an exponentially long lifetime, it may well be
today's universe. We investigate specific scenarios based on this quantum
diffusion property of the cosmic landscape and find a plausible scenario for
the early universe. In the last fast tunneling to the $\Lambda_0$
($<\Lambda_c$) site in this scenario, all energies are stored in the nucleation
bubble walls, which are released to radiation only after bubble collisions and
thermalization. So the $\Lambda_0$ site is chosen even if $\Lambda_0$ plus
radiation is larger than $\Lambda_c$, as long as the radiation does not
destabilize the $\Lambda_0$ vacuum. A consequence is that inflation must happen
before this last fast tunneling, so the inflationary scenario that emerges
naturally is extended brane inflation, where the brane motion includes a
combination of rolling, fast tunnelings, slow-roll, hopping and percolation in
the landscape. We point out that, in the brane world, radiation during
nucleosynthesis are mostly on the standard model branes (brane radiation, as
opposed to radiation in the bulk). This distinction may lead to interesting
dynamics. We consider this paper as a road map for future investigations.


title:
Scaling and super-universality in the coarsening dynamics of the 3d
  random field Ising model

abstract:
  We study the coarsening dynamics of the three-dimensional random field Ising
model using Monte Carlo numerical simulations. We test the dynamic scaling and
super-scaling properties of global and local two-time observables. We treat in
parallel the three-dimensional Edward-Anderson spin-glass and we recall results
on Lennard-Jones mixtures and colloidal suspensions to highlight the common and
different out of equilibrium properties of these glassy systems.


title:
Examples of smooth maps with finitely many critical points in dimensions
  $(4,3)$, $(8,5)$ and $(16,9)$

abstract:
  We consider manifolds $M^{2n}$ which admit smooth maps into a connected sum
of $S^1\times S^n$ with only finitely many critical points, for
$n\in\{2,4,8\}$, and compute the minimal number of critical points.


title: An approach to control collaborative processes in PLM systems

abstract:
  Companies that collaborate within the product development processes need to
implement an effective management of their collaborative activities. Despite
the implementation of a PLM system, the collaborative activities are not
efficient as it might be expected. This paper presents an analysis of the
problems related to the collaborative work using a PLM system. From this
analysis, we propose an approach for improving collaborative processes within a
PLM system, based on monitoring indicators. This approach leads to identify and
therefore to mitigate the brakes of the collaborative work.


title: On the time evolution of Wigner measures for Schrodinger equations

abstract:
  In this survey, our aim is to emphasize the main known limitations to the use
of Wigner measures for Schrodinger equations. After a short review of
successful applications of Wigner measures to study the semi-classical limit of
solutions to Schrodinger equations, we list some examples where Wigner measures
cannot be a good tool to describe high frequency limits. Typically, the Wigner
measures may not capture effects which are not negligible at the pointwise
level, or the propagation of Wigner measures may be an ill-posed problem. In
the latter situation, two families of functions may have the same Wigner
measures at some initial time, but different Wigner measures for a larger time.
In the case of systems, this difficulty can partially be avoided by considering
more refined Wigner measures such as two-scale Wigner measures; however, we
give examples of situations where this quadratic approach fails.


title: Regularization with the Smooth-Lasso procedure

abstract:
  We consider the linear regression problem. We propose the S-Lasso procedure
to estimate the unknown regression parameters. This estimator enjoys sparsity
of the representation while taking into account correlation between successive
covariates (or predictors). The study covers the case when $p\gg n$, i.e. the
number of covariates is much larger than the number of observations. In the
theoretical point of view, for fixed $p$, we establish asymptotic normality and
consistency in variable selection results for our procedure. When $p\geq n$, we
provide variable selection consistency results and show that the S-Lasso
achieved a Sparsity Inequality, i.e., a bound in term of the number of non-zero
components of the oracle vector. It appears that the S-Lasso has nice variable
selection properties compared to its challengers. Furthermore, we provide an
estimator of the effective degree of freedom of the S-Lasso estimator. A
simulation study shows that the S-Lasso performs better than the Lasso as far
as variable selection is concerned especially when high correlations between
successive covariates exist. This procedure also appears to be a good
challenger to the Elastic-Net (Zou and Hastie, 2005).


title: Black Hole Lasers Revisited

abstract:
  The production of Hawking radiation by a single horizon is not dependent on
the high-frequency dispersion relation of the radiated field. When there are
two horizons, however, Corley and Jacobson have shown that superluminal
dispersion leads to an amplification of the particle production in the case of
bosons. The analytic theory of this "black hole laser" process is quite
complicated, so we provide some numerical results in the hope of aiding
understanding of this interesting phenomenon. Specifically, we consider sonic
horizons in a moving fluid. The theory of elementary excitations in a
Bose-Einstein condensate provides an example of "superluminal" (Bogoliubov)
dispersion, so we add Bogoliubov dispersion to Unruh's equation for sound in
the fluid. A white-hole/black-hole horizon pair will then display black hole
lasing. Numerical analysis of the evolution of a wave packet gives a clear
picture of the amplification process. By utilizing the similarity of a
radiating horizon to a parametric amplifier in quantum optics we also analyze
the black hole laser as a quantum-optical network.


title: Creating kinks from particles

abstract:
  We study the creation of solitons from particles, using the $\lambda \phi^4$
model as a prototype. We consider the scattering of small, identical, wave
pulses, that are equivalent to a sequence of particles, and find that
kink-antikink pairs are created for a large region in parameter space. We also
find that scattering at {\it low} velocities is favorable for creating solitons
that have large energy compared to the mass of a particle.


title: Fano-Rashba effect in quantum dots

abstract:
  We consider the electronic transport through a Rashba quantum dot coupled to
ferromagnetic leads. We show that the interference of localized electron states
with resonant electron states leads to the appearance of the Fano-Rashba
effect. This effect occurs due to the interference of bound levels of
spin-polarized electrons with the continuum of electronic states with an
opposite spin polarization. We investigate this Fano-Rashba effect as a
function of the applied magnetic field and Rashba spin-orbit coupling.


title: Higgs boson mass in supersymmetry to three loops

abstract:
  Within the minimal supersymmetric extension of the Standard Model, the mass
of the light CP-even Higgs boson is computed to three-loop accuracy, taking
into account the next-to-next-to-leading order effects from supersymmetric
Quantum Chromodynamics. We consider two different scenarios for the mass
hierarchies of the supersymmetric spectrum. Our numerical results amount to
corrections of about 500 MeV which is of the same order as the experimental
accuracy expected at the CERN Large Hadron Collider (LHC).


title: Solution of the Matrix Hamiltonians via asymptotic iteration method

abstract:
  A method is suggested to obtain solutions of the various quantum optical
Hamiltonians in the framework of the asymptotic iteration method. We extend the
notion of asymptotic iteration method to solve the 2 \times 2 matrix
Hamiltonians. On a particular case, eigenvalues of the Rabi and Rashba
Hamiltonians are computed. The method presented here reproduces a number of
earlier results in a natural way as well as leads to a novel findings. Possible
generalizations of the method are also suggested.


title: Disentangling the Galaxy at low Galactic latitudes

abstract:
  We have used the field stars from the open cluster survey BOCCE, to study
three low-latitude fields imaged with the Canada-France-Hawaii telescope
(CFHT), with the aim of better understanding the Galactic structure in those
directions. Due to the deep and accurate photometry in these fields, they
provide a powerful discriminant among Galactic structure models. In the present
paper we discuss if a canonical star count model, expressed in terms of thin
and thick disc radial scales, thick disc normalization and reddening
distribution, can explain the observed CMDs. Disc and thick disc are described
with double exponentials, the spheroid is represented with a De Vaucouleurs
density law. In order to assess the fit quality of a particular set of
parameters, the colour distribution and luminosity function of synthetic
photometry is compared to that of target stars selected from the blue sequence
of the observed colour-magnitude diagrams. Through a Kolmogorov-Smirnov test we
find that the classical decomposition halo-thin/thick disc is sufficient to
reproduce the observations--no additional population is strictly necessary. In
terms of solutions common to all three fields, we have found a thick disc scale
length that is equal to (or slightly longer than) the thin disc scale.


title: Heat content

abstract:
  We study the heat content asymptotics with either Dirichlet or Robin boundary
conditions where the initial temperature exhibits radial blowup near the
boundary. We show that there is a complete small-time asymptotic expansion and
give explicit geometrical formulas for the first few terms in the expansion.


title: Spaces of $\mathbb R$ - places of rational function fields

abstract:
  In the paper an answer to a problem "When different orders of R(X) (where R
is a real closed field) lead to the same real place ?" is given. We use this
result to show that the space of $\mathbb R$-places of the field
$\textbf{R}(Y)$ (where \textbf{R} is any real closure of $\mathbb R(X)$) is not
metrizable space. Thus the space $M(\mathbb R(X,Y))$ is not metrizable, too.


title: New pulsar rotation measures and the Galactic magnetic field

abstract:
  We measured a sample of 150 pulsar Rotation Measures (RMs) using the 20-cm
receiver of the Parkes 64-m radio telescope. 46 of the pulsars in our sample
have not had their RM values previously published, whereas 104 pulsar RMs have
been revised. We used a novel quadratic fitting algorithm to obtain an accurate
RM from the calibrated polarisation profiles recorded across 256 MHz of
receiver bandwidth. The new data are used in conjunction with previously known
Dispersion Measures (DMs) and the NE2001 electron-density model to study models
of the direction and magnitude of the Galactic magnetic field.


title:
Standard Model Handles and Candles Working Group: Tools and Jets Summary
  Report

abstract:
  This report summarizes the activity on comparisons of existings tools for the
standard model and on issues in jet physics by the SMHC working group during
and subsequent to the Workshop "Physics at TeV Colliders", Les Houches, France,
11-29 June, 2007.


title:
Medium-resolution spectroscopy of FORJ0332-3557: Probing the
  interstellar medium and stellar populations of a lensed Lyman-break galaxy at
  z=3.77

abstract:
  We recently reported the discovery of FORJ0332-3557, a lensed Lyman-break
galaxy at z=3.77 in a remarkable example of strong galaxy-galaxy gravitational
lensing. We present here a medium-resolution rest-frame UV spectrum of the
source, which appears to be similar to the well-known Lyman-break galaxy
MS1512-cB58 at z=2.73. The spectral energy distribution is consistent with a
stellar population of less than 30 Ma, with an extinction of A(V)=0.5 mag and
an extinction-corrected star formation rate SFR(UV) of 200-300 Msun/a. The
Lyman-alpha line exhibits a damped profile in absorption produced by a column
density of about N(HI) = (2.5+_1.0) 10^21 atoms/cm^2, superimposed on an
emission line shifted both spatially (0.5 arcsec with respect to the UV
continuum source) and in velocity space (+830 km/s with respect to the
low-ionisation absorption lines from its interstellar medium), a clear
signature of outflows with an expansion velocity of about 270 km/s. A strong
emission line from HeII 164.04nm indicates the presence of Wolf-Rayet stars and
reinforces the interpretation of a very young starburst. The metallic lines
indicate sub-solar abundances of elements Si, Al, and C in the ionised gas
phase.


title: On the Duality between l^1-Homology and Bounded Cohomology

abstract:
  We modify the definition of l^1-homology and argue why our definition is more
adequate than the classical one. While we cannot reconstruct the classical
l^1-homology from the new definition for various reasons, we can reconstruct
its Hausdorffification so that no information concerning semi-norms is lost. We
obtain an axiomatic characterization of our l^1-homology as a universal
delta-functor and prove that it is pre-dual to our definition of bounded
cohomology. We thus answer a question raised by Loeh in her thesis. Moreover,
we prove Gromov's theorem and the Matsumoto-Morita conjecture in our context.


title:
Spectroscopic monitoring of Southern Galactic O and WN stars: State of
  the Art in 2007

abstract:
  We are conducting a spectroscopic monitoring of O and WN -type stars in our
Galaxy. In this work, we summarize some of our first results related to the
search for radial-velocity variations indicative of orbital motion.


title: Chandra and H.E.S.S. observations of the Supernova Remnant CTB 37B

abstract:
  The >100 GeV gamma-ray source, HESS J1713-381, apparently associated with the
shell-type supernova remnant (SNR) CTB 37B, was discovered using H.E.S.S. in
2006. X-ray follow-up observations with Chandra were performed in 2007 with the
aim of identifying a synchrotron counterpart to the TeV source and/or thermal
emission from the SNR shell. These new Chandra data, together with additional
TeV data, allow us to investigate the nature of this object in much greater
detail than was previously possible. The new X-ray data reveal thermal emission
from a ~4' region in close proximity to the radio shell of CTB 37B. The
temperature of this emission implies an age for the remnant of ~5000 years and
an ambient gas density of ~0.5 cm-3. Both these estimates are considerably
uncertain due to the asymmetry of the SNR and possible modifications of the
kinematics due to efficient cosmic ray (CR) acceleration. A bright (~7x10-13erg
cm-2s-1) and unresolved (<1'') source (CXOU J171405.7-381031) with a soft
(\Gamma ~3.3) non-thermal spectrum is also detected in coincidence with the
radio shell. Absorption indicates a column density consistent with the thermal
emission from the shell suggesting a genuine association rather than a chance
alignment. The observed TeV morphology is consistent with an origin in the
complete shell of CTB 37B. The lack of diffuse non-thermal X-ray emission
suggests an origin of the gamma-ray emission via the decay of neutral pions
produced in interactions of protons and nuclei, rather than inverse Compton
(IC) emission from relativistic electrons.


title:
Real space Bogolubov-de Gennes equations study of the boson-fermion
  model

abstract:
  The boson-fermion (BF) model has been proposed to describe superconductivity
in short coherence length superconductors. In this work we use it to study
impurity induced inhomogeneities in high temperature superconductors (HTS) as
found in numerous scanning tunnelling measurements. The model has been
formulated in real space and solved with help of Bogolubov-de Gennes approach.
Disorder in the boson or fermion subsystem is directly coupled to the
superconducting order parameter and leads to severe changes of superconducting
properties like local order parameter and density of states. We present the
results for many impurities randomly distributed over otherwise clean and
periodic two-dimensional square lattice.


title: Supersymmetric coloured/hairy black holes

abstract:
  We discus all possible spherically symmetric black hole type solutions to an
N=2 supergravity model with SO(3) gauging. The solutions consist of a one
parameter family illustrating that the no-hair theorem does not hold and an
isolated solution that a supersymmetric analogue of a coloured black hole.


title: On Six Dimensional Fundamental Superstrings as Holograms

abstract:
  In this note we discuss a possible holographic dual of the two dimensional
conformal field theory associated with the world-sheet of a macroscopic
superstring in a compactification on four-torus. We assume the near horizon
geometry of the black string has symmetries of $AdS_3\times S^3\times T^4$ and
construct a sigma model in the bulk. Analyzing the symmetries of the bulk
theory and comparing them with those of the CFT in a special light-cone gauge
we find agreement between global symmetries. Due to non-standard gauge
realization it is not clear how affine symmetries can be realized.


title: Successful description of exclusive vector meson electroproduction

abstract:
  Data for the differential cross sections for $\gamma^* p\to\rho^0 p$,
$\gamma^* p \to \phi p$ and $\gamma^* p\to J/\psi p$, at all available values
of $Q^2$, fit very well to a combination of soft pomeron, hard pomeron and
$f_2$ exchange.


title: Pseudo-unitarizable weight modules over generalized Weyl algebras

abstract:
  We define a notion of pseudo-unitarizability for weight modules over a
generalized Weyl algebra (of rank one, with commutative coeffiecient ring $R$),
which is assumed to carry an involution of the form $X^*=Y$, $R^*\subseteq R$.
We prove that a weight module $V$ is pseudo-unitarizable iff it is isomorphic
to its finitistic dual $V^\sharp$. Using the classification of weight modules
by Drozd, Guzner and Ovsienko, we obtain necessary and sufficient conditions
for an indecomposable weight module to be isomorphic to its finitistic dual,
and thus to be pseudo-unitarizable. Some examples are given, including
$U_q(\mathfrak{sl}_2)$ for $q$ a root of unity.


title:
Energy spectra of gamma-rays, electrons and neutrinos produced at
  interactions of relativistic protons with low energy radiation

abstract:
  We derived simple analytical parametrizations for energy distributions of
photons, electrons, and neutrinos produced in interactions of relativistic
protons with an isotropic monochromatic radiation field. The results on
photomeson processes are obtained using numerical simulations of proton-photon
interactions based on the public available Monte-Carlo code SOPHIA. For
calculations of energy spectra of electrons and positrons from the pair
production (Bethe-Heitler) process we suggest a simple formalism based on the
well-known differential cross-section of the process in the rest frame of the
proton. The analytical presentations of energy distributions of photons and
leptons provide a simple but accurate approach for calculations of broad-band
energy spectra of gamma-rays and neutrinos in cosmic proton accelerators
located in radiation dominated environments.


title:
Rectifying the thermal Brownian motion of three-dimensional asymmetric
  objects

abstract:
  We extend the analysis of a thermal Brownian motor reported in Phys. Rev.
Lett. 93, 090601 (2004) by C. Van den Broeck, R. Kawai, and P. Meurs to a
three-dimensional configuration. We calculate the friction coefficient,
diffusion coefficient, and drift velocity as a function of shape and present
estimates based on physically realistic parameter values.


title: Loewner's torus inequality with isosystolic defect

abstract:
  We show that Bonnesen's isoperimetic defect has a systolic analog for
Loewner's torus inequality. The isosystolic defect is expressed in terms of the
probabilistic variance of the conformal factor of the metric g with respect to
the flat metric of unit area in the conformal class of g.


title: Constructing Weyl group multiple Dirichlet series

abstract:
  Let Phi be a reduced root system of rank r. A Weyl group multiple Dirichlet
series for Phi is a Dirichlet series in r complex variables s_1,...,s_r,
initially converging for Re(s_i) sufficiently large, that has meromorphic
continuation to C^r and satisfies functional equations under the
transformations of C^r corresponding to the Weyl group of Phi. A heuristic
definition of such series was given in [2], and they have been investigated in
certain special cases in [2-6, 11-14]. In this paper we generalize results in
[13] to construct Weyl group multiple Dirichlet series by a uniform method, and
show in all cases that they have the expected properties.


title:
Oxygen isotope anomalies of the Sun and the original environment of the
  Solar system

abstract:
  We present results from a model of oxygen isotopic anomaly production through
selective photodissociation of CO within the collapsing proto-Solar cloud. Our
model produces a proto-Sun with a wide range of Delta_17O values depending on
the intensity of the ultraviolet radiation field. Dramatically different
results from two recent Solar wind oxygen isotope measurements indicate that a
variety of compositions remain possible for the solar oxygen isotope
composition. However, constrained by other measurements from comets and
meteorites, our models imply the birth of the Sun in a stellar cluster with an
enhanced radiation field and are therefore consistent with a supernova source
for 60Fe in meteorites.


title:
First-principles calculation of electronic polarization of III-V
  nanotubes

abstract:
  A first-principles study of the electronic polarization of BN and AlN
nanotubes and their graphitic sheets under an external electric field has been
performed. We found that the polarization per atom of zigzag nanotubes
increases with decreasing diameter while that of armchair nanotubes decreases.
The variation of the polarization is related to the exterior angle of the bonds
around the B or Al atoms rather than that around the N atoms. The increase in
the polarization of the zigzag nanotubes with decreasing diameter is caused by
the large variation of the exterior angle when they are wrapped into the
tubular form. On the other hand, the decrease in the bond length results in the
weak polarization of thin armchair nanotubes.


title: Is the CMB cold spot a gate to extra dimensions?

abstract:
  One of the most striking features found in the cosmic microwave background
data is the presence of an anomalous Cold Spot (CS) in the temperature maps
made by the Wilkinson Microwave Anisotropy Probe (WMAP). This CS has been
interpreted as the result of the presence of a collapsing texture, perhaps
coming from some early universe Grand Unified Theory (GUT) phase transition. In
this work we propose an alternative explanation based on a completely different
kind of texture which appears in a natural way in a broad class of brane-world
models. This type of textures known as brane-skyrmions can be understood as
holes in the brane which make possible to pass through them along the
extra-dimensional space. The typical scales needed for the proposed
brane-skyrmions to correctly describe the observed CS can be as low as the
electroweak scale.


title: Matching NLLA+NNLO for event shape distributions

abstract:
  We study the matching of the next-to-leading logarithmic approximation (NLLA)
onto the fixed next-to-next-to-leading order (NNLO) calculation for event shape
distributions in electron-positron annihilation. The resulting theoretical
predictions combine all precision QCD knowledge on the distributions, and are
theoretically reliable over an extended kinematical range. Compared to
previously available matched NLLA+NLO and fixed order NNLO results, we observe
that the effects of the combined NLLA+NNLO are small in the three-jet region,
relevant for precision physics.


title: Can one measure C-odd asymmetry in e+e- --> pi+pi-

abstract:
  C-odd asymmetry can be studied from an accurate measurement of the angular
distribution due to the interference between the S- and P-waves in e+e- --> pi+
pi- at order alpha^3. The asymmetry is dominated by the pion rescattering
diagram which is enhanced by the presence of the ln(s/m^2_e), and is quite
large (10% at theta=30^0 and sqrt{s} < M_{f_2}) compared to alpha/pi=0.3%. This
process can also be used for alternatively measuring the size of the
rescattering term and the phase of the S-wave amplitude, but does not help to
solve the present discrepancy between the hadronic spectral functions from e+e-
and tau-decay data.


title:
Quantum Monodromy and Non-concentration near a Closed Semi-Hyperbolic
  Orbit

abstract:
  For a large class of semiclassical operators $P(h)-z$ which includes
Schr\"odinger operators on manifolds with boundary, we construct the Quantum
Monodromy operator $M(z)$ associated to a periodic orbit $\gamma$ of the
classical flow. Using estimates relating $M(z)$ and $P(h)-z$, we prove
semiclassical estimates for small complex perturbations of $P(h) -z$ in the
case $\gamma$ is semi-hyperbolic. As our main application, we give logarithmic
lower bounds on the mass of eigenfunctions away from semi-hyperbolic orbits of
the associated classical flow.
  As a second application of the Monodromy Operator construction, we prove if
$\gamma$ is an elliptic orbit, then $P(h)$ admits quasimodes which are
well-localized near $\gamma$.


title: Large-N Solution of the Heterotic N=(0,2) Two-Dimensional CP(N-1) Model

abstract:
  We continue explorations of non-Abelian strings, focusing on the solution of
a heterotic deformation of the CP(N-1) model with an extra right-handed fermion
field and N=(0,2) supersymmetry. This model emerges as a low-energy theory on
the worldsheet of the BPS-saturated flux tubes (strings) in N=2 supersymmetric
QCD deformed by a superpotential of a special type breaking N=2 supersymmetry
down to N=1. Using large-N expansion we solve this model to the leading order
in 1/N. Our solution exhibits spontaneous supersymmetry breaking for all values
of the deformation parameter. We identify the Goldstino field. The discrete
Z_{2N} symmetry is shown to be spontaneously broken down to Z_2; therefore, the
worldsheet model has N strictly degenerate vacua (with nonvanishing vacuum
energy). Thus, the heterotic CP(N-1) model is in the deconfinement phase. We
can compare this dynamical pattern, on the one hand, with the N=(2,2) CP(N-1)
model which has N degenerate vacua with unbroken supersymmetry, and, on the
other hand, with nonsupersymmetric CP(N-1) model with split quasivacua and the
Coulomb/confining phase. We determine the mass spectrum of the heterotic
CP(N-1) model in the large-N limit.


title: High-Altitude Emission from Pulsar Slot Gaps: The Crab Pulsar

abstract:
  We present results of a 3D model of optical to gamma-ray emission from the
slot gap accelerator of a rotation-powered pulsar. Primary electrons
accelerating to high-altitudes in the unscreened electric field of the slot gap
reach radiation-reaction limited Lorentz factors of 2 x 10^7, while
electron-positron pairs from lower-altitude cascades flow along field lines
interior to the slot gap. The curvature, synchrotron and inverse Compton
radiation of both primary electrons and pairs produce a broad spectrum of
emission from infra-red to GeV energies. Both primaries and pairs undergo
cyclotron resonant absorption of radio photons, allowing them to maintain
significant pitch angles. Synchrotron radiation from pairs with a power-law
energy spectrum with Lorentz factors 10^2 - 10^5, dominate the spectrum up to
10 MeV. Synchrotron and curvature radiation of primaries dominates from 10 MeV
up to a few GeV. We examine the energy-dependent pulse profiles and
phase-resolved spectra for parameters of the Crab pulsar as a function of
magnetic inclination and viewing angle, comparing to broad-band data. In most
cases, the pulse profiles are dominated by caustics on trailing field lines. We
also explore the relation of the high-energy and the radio profiles, as well as
the possibility of caustic formation in the radio cone emission. We find that
the Crab pulsar profiles and spectrum can be reasonably well reproduced by a
model with viewing angle 45 degrees and inclination angle 100 or 80 degrees.
This model predicts that the slot gap emission below 200 MeV will exhibit
correlations in time and phase with the radio emission.


title: A Generalization of Siegel's Theorem and Hall's Conjecture

abstract:
  Consider an elliptic curve, defined over the rational numbers, and embedded
in projective space. The rational points on the curve are viewed as integer
vectors with coprime coordinates. What can be said about a rational point if a
bound is placed upon the number of prime factors dividing a fixed coordinate?
If the bound is zero, then Siegel's Theorem guarantees that there are only
finitely many such points. We consider, theoretically and computationally, two
conjectures: one is a generalization of Siegel's Theorem and the other is a
refinement which resonates with Hall's conjecture.


title: Spanning directed trees with many leaves

abstract:
  The {\sc Directed Maximum Leaf Out-Branching} problem is to find an
out-branching (i.e. a rooted oriented spanning tree) in a given digraph with
the maximum number of leaves. In this paper, we obtain two combinatorial
results on the number of leaves in out-branchings. We show that
  - every strongly connected $n$-vertex digraph $D$ with minimum in-degree at
least 3 has an out-branching with at least $(n/4)^{1/3}-1$ leaves;
  - if a strongly connected digraph $D$ does not contain an out-branching with
$k$ leaves, then the pathwidth of its underlying graph UG($D$) is $O(k\log k)$.
Moreover, if the digraph is acyclic, the pathwidth is at most $4k$.
  The last result implies that it can be decided in time $2^{O(k\log^2 k)}\cdot
n^{O(1)}$ whether a strongly connected digraph on $n$ vertices has an
out-branching with at least $k$ leaves. On acyclic digraphs the running time of
our algorithm is $2^{O(k\log k)}\cdot n^{O(1)}$.


title:
Discovery of a VHE gamma-ray source coincident with the supernova
  remnant CTB 37A

abstract:
  The supernova remnant (SNR) complex CTB 37 is an interesting candidate for
observations with Very High Energy (VHE) gamma-ray telescopes such as H.E.S.S.
In this region, three SNRs are seen. One of them is potentially associated with
several molecular clouds, a circumstance that can be used to probe the
acceleration of hadronic cosmic rays. This region was observed with the
H.E.S.S. Cherenkov telescopes and the data were analyzed with standard H.E.S.S.
procedures. Recent X-ray observations with Chandra and XMM-Newton were used to
search for X-ray counterparts. The discovery of a new VHE gamma-ray source HESS
J1714-385 coincident with the remnant CTB 37A is reported. The energy spectrum
is well described by a power-law with a photon index of Gamma =2.30pm0.13 and a
differential flux at 1 TeV of Phi_0 = (8.7 pm 1.0_{stat} pm
1.8_{sys})x10^{-13}cm^{-2}s^{-1}TeV^{-1}. The integrated flux above 1 TeV is
equivalent to 3% of the flux of the Crab nebula above the same energy. This VHE
gamma-ray source is a counterpart candidate for the unidentified EGRET source
3EG J1714-3857. The observed VHE emission is consistent with the molecular gas
distribution around CTB 37A; a close match is expected in a hadronic scenario
for gamma-ray production. The X-ray observations reveal the presence of thermal
X-rays from the NE part of the SNR. In the NW part of the remnant, an extended
non-thermal X-ray source, CXOU J171419.8-383023, is discovered as well.
Possible connections of the X-ray emission to the newly found VHE source are
discussed.


title: Riemann Surface Laminations with Singularities

abstract:
  In these introductory notes we give the basics of the theory of holomorphic
foliations and laminations. The emphasis is on the theory of harmonic currents
and unique ergodicity for laminations transversally Lipschitz in CP^2 and for
generic holomorphic foliations in CP^2.


title:
Micromagnetic study of a spin-torque oscillator based on a magnetic
  nano-contact magnetized at an arbitrary angle

abstract:
  The nature of spin wave modes excited by spin-polarized direct current in a
spin-torque auto-oscillator based on a magnetic nanocontact was studied by a
micromagnetic simulation in the case when the external bias magnetic field was
rotated from the in-plane to perpendicular-to-plane orientation. In qualitative
agreement with the weakly-nonlinear analytical theory it was found, that at a
certain critical angle, an abrupt switching from the self-localized nonlinear
"bullet" mode to a propagating quasi-linear Slonczewski mode takes place, and
is accompanied by an upward jump in generated microwave frequency. It was,
also, found that the analytical theory overestimates the magnitude of a
critical magnetization angle, corresponding to the mode switching, and that the
magnitude of the frequency jump caused by the mode switching is inversely
proportional to the nanocontact radius.


title:
Gaussian matrix model in an external field and non-intersecting Brownian
  motions

abstract:
  We study the Gaussian hermitian random matrix ensemble with an external
matrix which has an arbitrary number of eigenvalues with arbitrary
multiplicity. We compute the limiting eigenvalues correlations when the size of
the matrix goes to infinity in non-critical regimes. We show that they exhibit
universal behavior and can be expressed with the Sine and Airy kernels. We also
briefly review the implication of these results in terms of non-intersecting
Brownian motions.


title:
Cross section and polarization observables for the reaction $e^++e^-\to
  a_1(1260)+\pi $

abstract:
  A model independent formalism for the electron positron annihilation reaction
$e^++e^-\to a_1(1260)+\pi $ has been derived. The differential and total cross
sections and the elements of the spin--density matrix of the $a_1$-meson were
calculated in terms of the electromagnetic form factors of the corresponding
$\gamma^*a_1\pi $ current. Simple models of $a_1$ form factors have been fitted
to the available cross section data and they allow to give numerical
predictions for the different observables.


title: Annular embeddings of permutations for arbitrary genus

abstract:
  In the symmetric group on a set of size 2n, let P_{2n} denote the conjugacy
class of involutions with no fixed points (equivalently, we refer to these as
``pairings'', since each disjoint cycle has length 2). Harer and Zagier
explicitly determined the distribution of the number of disjoint cycles in the
product of a fixed cycle of length 2n and the elements of P_{2n}. Their famous
result has been reproved many times, primarily because it can be interpreted as
the genus distribution for 2-cell embeddings in an orientable surface,of a
graph with a single vertex attached to n loops. In this paper we give a new
formula for the cycle distribution when a fixed permutation with two cycles
(say the lengths are p,q, where p+q=2n) is multiplied by the elements of
P_{2n}. It can be interpreted as the genus distribution for 2-cell embeddings
in an orientable surface, of a graph with two vertices, of degrees p and q. In
terms of these graphs, the formula involves a parameter that allows us to
specify, separately, the number of edges between the two vertices and the
number of loops at each of the vertices. The proof is combinatorial, and uses a
new algorithm that we introduce to create all rooted forests containing a given
rooted forest.


title:
Method for Full Bloch-Sphere Control of a Localized Spin via a Single
  Electrical Gate

abstract:
  We calculate the dependence on an applied electric field of the g tensor of a
single electron in a self-assembled InAs/GaAs quantum dot. We identify dot
sizes and shapes for which one in-plane component of the g tensor changes sign
for realistic electric fields, and show this should permit full Bloch-sphere
control of the electron spin in the quantum dot using only a static magnetic
field and a single vertical electric gate.


title:
Slow decay of concentration variance due to no-slip walls in chaotic
  mixing

abstract:
  Chaotic mixing in a closed vessel is studied experimentally and numerically
in different 2-D flow configurations. For a purely hyperbolic phase space, it
is well-known that concentration fluctuations converge to an eigenmode of the
advection-diffusion operator and decay exponentially with time. We illustrate
how the unstable manifold of hyperbolic periodic points dominates the resulting
persistent pattern. We show for different physical viscous flows that, in the
case of a fully chaotic Poincare section, parabolic periodic points at the
walls lead to slower (algebraic) decay. A persistent pattern, the backbone of
which is the unstable manifold of parabolic points, can be observed. However,
slow stretching at the wall forbids the rapid propagation of stretched
filaments throughout the whole domain, and hence delays the formation of an
eigenmode until it is no longer experimentally observable. Inspired by the
baker's map, we introduce a 1-D model with a parabolic point that gives a good
account of the slow decay observed in experiments. We derive a universal decay
law for such systems parametrized by the rate at which a particle approaches
the no-slip wall.


title: Tunneling conductance of amine linked alkyl chains

abstract:
  The tunneling transport theory developed in Phys. Rev. B {\bf 76}, 115102
(2007) is applied to molecular devices made of alkyl chains linked to gold
electrodes via amine groups. Using the analytic expression of the tunneling
conductance derived in our previous work, we identify the key physical
quantities that characterize the conductance of these devices. By investigating
the transport characteristics of three devices, containing 4, 6, and 8 methyl
groups, we extract the dependence of the tunneling conductance on the chain's
length, which is an exponential decay law in close agreement with recent
experimental data.


title:
Ultimate field-free molecular alignment by combined adiabatic-impulsive
  field design

abstract:
  We show that a laser pulse designed as an adiabatic ramp followed by a kick
allows one to reach a perfect postpulse molecular alignment, free of
saturation. The mechanism is based on an optimized distribution of the energy
between a weakly efficient but non saturating adiabatic ramp and an efficient
but saturating impulsive field. Unprecedent degrees of alignment are predicted
using state-of-the-art pulse shaping techniques and non-destructive field
intensities. The scheme can be extended to reach high degrees of orientation of
polar molecules using designed half-cycle pulses.


title: The Liquid Blister Test

abstract:
  We consider a thin elastic sheet adhering to a stiff substrate by means of
the surface tension of a thin liquid layer. Debonding is initiated by imposing
a vertical displacement at the centre of the sheet and leads to the formation
of a delaminated region, or `blister'. This experiment reveals that the
perimeter of the blister takes one of three different forms depending on the
vertical displacement imposed. As this displacement is increased, we observe
first circular, then undulating and finally triangular blisters. We obtain
theoretical predictions for the observed features of each of these three
families of blisters. The theory is built upon the F\"{o}ppl-von K\'{a}rm\'{a}n
equations for thin elastic plates and accounts for the surface energy of the
liquid. We find good quantitative agreement between our theoretical predictions
and experimental results, demonstrating that all three families are governed by
different balances between elastic and capillary forces. Our results may bear
on micrometric tapered devices and other systems where elastic and adhesive
forces are in competition.


title:
Spin-orbit coupling, edge states and quantum spin Hall criticality due
  to Dirac fermion confinement: The case study of graphene

abstract:
  We propose a generalized Dirac fermion description for the electronic state
of graphene terminated by a zigzag edge. This description admits a spin-orbit
coupling needed to preserve time-reversal invariance of the zigzag confinement,
otherwise, for spinless particles, showing the parity anomaly typical of
quantum electrodynamics in (2+1) dimensions. At a certain critical strength the
spin-orbit coupling induces a phase transition of the quantum-spin-Hall type.
It is manifested by a novel type of the edge states consisting of a Kramers'
pair of counter-propagating modes with opposite spin orientations. Such edge
states are capable of accumulating an integer spin in response to a transverse
electric field in the absence of a magnetic one. They exist without any
excitation gap in the bulk, due to which our system stands out among other
quantum spin Hall systems studied earlier. We show that at the transition the
local density of states is discontinuous and its energy dependence reflects the
phase diagram of the system.


title:
Distribution of magnetic domain pinning fields in GaMnAs ferromagnetic
  films

abstract:
  Using the angular dependence of the planar Hall effect in GaMnAs
ferromagnetic films, we were able to determine the distribution of magnetic
domain pinning fields in this material. Interestingly, there is a major
difference between the pinning field distribution in as-grown and in annealed
films, the former showing a strikingly narrower distribution than the latter.
This conspicuous difference can be attributed to the degree of non-uniformity
of magnetic anisotropy in both types of films. This finding provides a better
understanding of the magnetic domain landscape in GaMnAs that has been the
subject of intense debate.


title:
Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations:
  Galactic Foreground Emission

abstract:
  We present a new estimate of foreground emission in the WMAP data, using a
Markov chain Monte Carlo (MCMC) method. The new technique delivers maps of each
foreground component for a variety of foreground models, error estimates of the
uncertainty of each foreground component, and provides an overall
goodness-of-fit measurement. The resulting foreground maps are in broad
agreement with those from previous techniques used both within the
collaboration and by other authors.
  We find that for WMAP data, a simple model with power-law synchrotron,
free-free, and thermal dust components fits 90% of the sky with a reduced
chi-squared of 1.14. However, the model does not work well inside the Galactic
plane. The addition of either synchrotron steepening or a modified spinning
dust model improves the fit. This component may account for up to 14% of the
total flux at Ka-band (33 GHz). We find no evidence for foreground
contamination of the CMB temperature map in the 85% of the sky used for
cosmological analysis.


title:
Discrete holomorphic geometry I. Darboux transformations and spectral
  curves

abstract:
  Finding appropriate notions of discrete holomorphic maps and, more generally,
conformal immersions of discrete Riemann surfaces into 3-space is an important
problem of discrete differential geometry and computer visualization. We
propose an approach to discrete conformality that is based on the concept of
holomorphic line bundles over "discrete surfaces", by which we mean the vertex
sets of triangulated surfaces with bi-colored set of faces. The resulting
theory of discrete conformality is simultaneously Moebius invariant and based
on linear equations. In the special case of maps into the 2-sphere we obtain a
reinterpretation of the theory of complex holomorphic functions on discrete
surfaces introduced by Dynnikov and Novikov. As an application of our theory we
introduce a Darboux transformation for discrete surfaces in the conformal
4-sphere. This Darboux transformation can be interpreted as the space- and
time-discrete Davey-Stewartson flow of Konopelchenko and Schief.


title: Immersed Lagrangian Floer Theory

abstract:
  Let (M,w) be a compact symplectic manifold, and L a compact, embedded
Lagrangian submanifold in M. Fukaya, Oh, Ohta and Ono construct Lagrangian
Floer cohomology for such M,L, yielding groups HF^*(L,b;\Lambda) for one
Lagrangian or HF^*((L,b),(L',b');\Lambda) for two, where b,b' are choices of
bounding cochains, and exist if and only if L,L' have unobstructed Floer
cohomology. These are independent of choices up to canonical isomorphism, and
have important invariance properties under Hamiltonian equivalence. Floer
cohomology groups are the morphism groups in the derived Fukaya category of
(M,w), and so are an essential part of the Homological Mirror Symmetry
Conjecture of Kontsevich.
  The goal of this paper is to extend all this to immersed Lagrangians L in M
with immersion i : L --> M, with transverse self-intersections. In the embedded
case, Floer cohomology HF^*(L,b;\Lambda) is a modified, 'quantized' version of
cohomology H^*(L;\Lambda) over the Novikov ring \Lambda. In our immersed case,
HF^*(L,b;\Lambda) turns out to be a quantized version of the sum of
H^*(L;\Lambda) with a \Lambda-module spanned by pairs (p,q) for p,q distinct
points of L with i(p)=i(q) in M.
  The theory becomes simpler and more powerful for graded Lagrangians in
Calabi-Yau manifolds, when we can work over a smaller Novikov ring
\Lambda_{CY}. The proofs involve associating a gapped filtered A-infinity
algebra over \Lambda or \Lambda_{CY} to i : L --> M, which is independent of
nearly all choices up to canonical homotopy equivalence, and is built using a
series of finite approximations called A_{N,0} algebras for N=0,1,2,...


title:
Short-range magnetic ordering process for the triangular lattice
  compound NiGa2S4: a positive muon spin rotation and relaxation study

abstract:
  We report a study of the triangular lattice Heisenberg magnet NiGa2S4 by the
positive muon spin rotation and relaxation technique. We unravel three
temperature regimes: (i) below T_c = 9.2(2) K a spontaneous static magnetic
field at the muon site is observed and the spin dynamics is appreciable: the
time scale of the modes we probe is ~ 7 ns; (ii) an unconventional stretched
exponential relaxation function is found for T_c < T < T_{cross} where
T_{cross} = 12.6 K, which is a signature of a multichannel relaxation for this
temperature range; (iii) above T_{cross}, the relaxation is exponential as
expected for a conventional compound. The transition at T_c is of the
continuous type. It occurs at a temperature slightly smaller than the
temperature at which the specific heat displays a maximum at low temperature.
This is reminiscent of the behavior expected for the
Berezinskii-Kosterlitz-Thouless transition. We argue that these results reflect
the presence of topological defects above T_c.


title: Fluctuation-Dissipation: Response Theory in Statistical Physics

abstract:
  General aspects of the Fluctuation-Dissipation Relation (FDR), and Response
Theory are considered. After analyzing the conceptual and historical relevance
of fluctuations in statistical mechanics, we illustrate the relation between
the relaxation of spontaneous fluctuations, and the response to an external
perturbation. These studies date back to Einstein's work on Brownian Motion,
were continued by Nyquist and Onsager and culminated in Kubo's linear response
theory.
  The FDR has been originally developed in the framework of statistical
mechanics of Hamiltonian systems, nevertheless a generalized FDR holds under
rather general hypotheses, regardless of the Hamiltonian, or equilibrium nature
of the system. In the last decade, this subject was revived by the works on
Fluctuation Relations (FR) concerning far from equilibrium systems. The
connection of these works with large deviation theory is analyzed.
  Some examples, beyond the standard applications of statistical mechanics,
where fluctuations play a major role are discussed: fluids, granular media,
nano-systems and biological systems.


title: On two examples by Iyama and Yoshino

abstract:
  In the recent paper "Mutation in triangulated categories and rigid
Cohen-Macaulay modules" Iyama and Yoshino consider two interesting examples of
isolated singularities over which it is possible to classify the indecomposable
maximal Cohen-Macaulay modules in terms of linear algebra data. In this paper
we present two new approaches to these examples. In the first approach we give
a relation with cluster categories. In the second approach we use Orlov's
result on the graded singularity category. We obtain some new results on the
singularity category of isolated singularities which may be interesting in
their own right.


title: Radio detections towards unidentified variable EGRET sources

abstract:
  Context. A considerable fraction of the gamma-ray sources discovered with the
Energetic Gamma-Ray Experiment Telescope (EGRET) remain unidentified. The EGRET
sources that have been properly identified are either pulsars or variable
sources at both radio and gamma-ray wavelengths. Most of the variable sources
are strong radio blazars.However, some low galactic-latitude EGRET sources,
with highly variable gamma-ray emission, lack any evident counterpart according
to the radio data available until now.
  Aims. The primary goal of this paper is to identify and characterise the
potential radio counterparts of four highly variable gamma-ray sources in the
galactic plane through mapping the radio surroundings of the EGRET confidence
contours and determining the variable radio sources in the field whenever
possible.
  Methods. We have carried out a radio exploration of the fields of the
selected EGRET sources using the Giant Metrewave Radio Telescope (GMRT)
interferometer at 21 cm wavelength, with pointings being separated by months.
  Results. We detected a total of 151 radio sources. Among them, we identified
a few radio sources whose flux density has apparently changed on timescales of
months. Despite the limitations of our search, their possible variability makes
these objects a top-priority target for multiwavelength studies of the
potential counterparts of highly variable, unidentified gamma-ray sources.


title:
Some remarks on varieties of pairs of commuting upper triangular
  matrices and an interpretation of commuting varieties

abstract:
  It is known that the variety of pairs of n x n commuting upper triangular
matrices isn't a complete intersection for infinitely many values of n; we show
that there exists m such that this happens if and only if n > m. We also show
that m < 18 and that it could be found by determining the dimension of the
variety of pairs of commuting strictly upper triangular matrices. Then we
define a natural map from the variety of pairs of commuting n x n matrices onto
a subvariety defined by linear equations of the grassmannian of subspaces of
codimension 2 of a vector space of dimension n x n.


title:
Vanishing Hall Coefficient in the Extreme Quantum Limit in
  Photocarrier-Doped SrTiO3

abstract:
  We have investigated the extreme quantum limit of photogenerated electrons in
quantum paraelectric SrTiO3. This regime is distinct from conventional
semiconductors, due to the large electron effective mass and large lattice
dielectric constant. At low temperature, the magnetoresistance and Hall
resistivity saturate at high magnetic field, deviating from conventional
behavior. As a result, the Hall coefficient vanishes on the scale of the ratio
of the Landau level splitting to the thermal energy, indicating the essential
role of lowest Landau level occupancy, as limited by thermal broadening.


title: Recurrence of the twisted planar random walk

abstract:
  We show that the "twisted" planar random walk - which results by summing up
stationary increments rotated by multiples of a fixed angle - is recurrent
under diverse assumptions on the increment process. For example, if the
increment process is alpha-mixing and of finite second moment, then the twisted
random walk is recurrent for every angle fixed choice of the angle out of a set
of full Lebesgue measure, no matter how slow the mixing coefficients decay.


title: Energy Current with Multi--body Interaction using Dirac Delta Function

abstract:
  Energy density and energy flux was introduced along Takesue's method.
Particle energies were localized at particle positions using Dirac delta
function. The energy density was connected with the energy flux by continuity
equation. New method was proposed to deal with multi--body interaction.
Consequently, the energy current between particles could be calculated even if
the multi--body interaction appeared. Moreover, An application to the molecular
dynamics simulation of hydrogen adsorption on a graphene with modified Brenner
reactive empirical bond order potential was demonstrated.


title: A quadratic algorithm for road coloring

abstract:
  The Road Coloring Theorem states that every aperiodic directed graph with
constant out-degree has a synchronized coloring. This theorem had been
conjectured during many years as the Road Coloring Problem before being settled
by A. Trahtman. Trahtman's proof leads to an algorithm that finds a
synchronized labeling with a cubic worst-case time complexity. We show a
variant of his construction with a worst-case complexity which is quadratic in
time and linear in space. We also extend the Road Coloring Theorem to the
periodic case.


title: A note on optimal probability lower bounds for centered random variables

abstract:
  In this note we obtain lower bounds for $\P(\xi\geq 0)$ and $\P(\xi>0)$ under
assumptions on the moments of a centered random variable $\xi$. The obtained
estimates are shown to be optimal and improve results from the literature. The
results are applied to obtain probability lower bounds for second order
Rademacher chaos.


title:
The elliptic curve discrete logarithm problem and equivalent hard
  problems for elliptic divisibility sequences

abstract:
  We define three hard problems in the theory of elliptic divisibility
sequences (EDS Association, EDS Residue and EDS Discrete Log), each of which is
solvable in sub-exponential time if and only if the elliptic curve discrete
logarithm problem is solvable in sub-exponential time. We also relate the
problem of EDS Association to the Tate pairing and the MOV, Frey-R\"{u}ck and
Shipsey EDS attacks on the elliptic curve discrete logarithm problem in the
cases where these apply.


title:
Isomorphisms between Algebras of Semiclassical Pseudodifferential
  Operators

abstract:
  Following the work of Duistermaat-Singer \cite{DS} on isomorphisms of
algebras of global pseudodifferential operators, we classify isomorphisms of
algebras of microlocally defined semiclassical pseudodifferential operators.
Specifically, we show that any such isomorphism is given by conjugation by $A =
BF$, where $B$ is a microlocally elliptic semiclassical pseudodifferential
operator, and $F$ is a microlocal $h$-FIO associated to the graph of a local
symplectic transformation.


title:
Investigation of the Vertical Movement of an Isothermal Line at the
  Density Maximum in H2O and D2O

abstract:
  We studied the cooling of a column of water, primarily in a freezer, and
analyzed the development and movement of an isothermal line at ~4 degC in H2O
and ~11 degC in D2O. Our experiments show that the vertical velocity of the
symmetrical isothermal line moving up the column of water is inversely
proportional to the diameter of the column of water. It has a measured maximum
velocity of 1.4 +/- 0.1 cm/min when the column diameter is 22 mm and decreases
to 0.4 +/- 0.1 cm/min when the diameter is increased to 125 mm. The measurement
of the velocity becomes increasingly difficult to obtain when the column
diameter is less than 22 mm because of the lack of complete development of the
isothermal line. The data and discussion presented in this paper raise serious
questions to the claim of new phase transitions in water made by S. Esposito,
et. al. 0704.1381


title:
Complexity Analysis of Reed-Solomon Decoding over GF(2^m) Without Using
  Syndromes

abstract:
  For the majority of the applications of Reed-Solomon (RS) codes, hard
decision decoding is based on syndromes. Recently, there has been renewed
interest in decoding RS codes without using syndromes. In this paper, we
investigate the complexity of syndromeless decoding for RS codes, and compare
it to that of syndrome-based decoding. Aiming to provide guidelines to
practical applications, our complexity analysis differs in several aspects from
existing asymptotic complexity analysis, which is typically based on
multiplicative fast Fourier transform (FFT) techniques and is usually in big O
notation. First, we focus on RS codes over characteristic-2 fields, over which
some multiplicative FFT techniques are not applicable. Secondly, due to
moderate block lengths of RS codes in practice, our analysis is complete since
all terms in the complexities are accounted for. Finally, in addition to fast
implementation using additive FFT techniques, we also consider direct
implementation, which is still relevant for RS codes with moderate lengths.
Comparing the complexities of both syndromeless and syndrome-based decoding
algorithms based on direct and fast implementations, we show that syndromeless
decoding algorithms have higher complexities than syndrome-based ones for high
rate RS codes regardless of the implementation. Both errors-only and
errors-and-erasures decoding are considered in this paper. We also derive
tighter bounds on the complexities of fast polynomial multiplications based on
Cantor's approach and the fast extended Euclidean algorithm.