December 2006 arXiv papers — page 18

S. P. Walborn, D. S. Tasca, M. P. Almeida, P. Pellat-Finet

This paper has been withdrawn due to a crucial theoretical error.

D. M. Alexander

Deep SCUBA surveys have uncovered a population of dust-enshrouded star-forming galaxies at z~2. Using the ultra-deep 2 Ms Chandra Deep Field-North survey we recently showed that a large fraction of these systems are also undergoing intense black-hole growth. Here we provide further constraints on the properties of the black holes in SCUBA galaxies using the

Bob Osano, Cyril Pitrou, Peter Dunsby, Jean-Philippe Uzan

The generation of gravitational waves during inflation due to the non-linear coupling of scalar and tensor modes is discussed. Two methods describing gravitational wave perturbations are used and compared: a covariant and local approach, as well as a metric-based analysis based on the Bardeen formalism. An application to slow-roll inflation is also described

D. M. Alexander

Deep X-ray surveys provide the most efficient identification of Active Galactic Nuclei (AGN) activity. However, recent evidence has indicated that the current <10 keV surveys do not detect the most heavily obscured AGNs. Here we explore whether the X-ray undetected AGN population can be identified within the ultra-deep Spitzer survey of the GOODS-N field usi

Pierre Sutra, Marc Shapiro, João Pedro Barreto

We study large-scale distributed cooperative systems that use optimistic replication. We represent a system as a graph of actions (operations) connected by edges that reify semantic constraints between actions. Constraint types include conflict, execution order, dependence, and atomicity. The local state is some schedule that conforms to the constraints; bec

Kenneth L. Baker

We determine the non-null homologous knots in lens spaces whose exteriors contain properly embedded once-punctured tori. All such knots arise as surgeries on the Whitehead link and are grid number 1 in their lens spaces. As a corollary, we classify once-punctured torus bundles that admit a lens space filling.

G. M. Bruun, H. Smith

The shear viscosity of a two-component Fermi gas in the normal phase is calculated as a function of temperature in the unitarity limit, taking into account strong-coupling effects that give rise to a pseudogap in the spectral density for single-particle excitations. The results indicate that recent measurements of the damping of collective modes in trapped a

Abhay Ashtekar, Tomasz Pawlowski, Parampreet Singh, Kevin Vandersloot

The closed, k=1, FRW model coupled to a massless scalar field is investigated in the framework of loop quantum cosmology using analytical and numerical methods. As in the k=0 case, the scalar field can be again used as emergent time to construct the physical Hilbert space and introduce Dirac observables. The resulting framework is then used to address a majo

Kanabu Nawa, Hideo Suganuma, Toru Kojo

We study the baryon in holographic QCD with $D4/D8/\bar{D8}$ multi-$D$ brane system. In holographic QCD, the baryon appears as a topologically non-trivial chiral soliton in a four-dimensional effective theory of mesons. We call this topological soliton as Brane-induced Skyrmion. Some review of $D4/D8/\bar{D8}$ holographic QCD is presented from the viewpoints

P. Romano, S. Campana, G. Chincarini, J. Cummings

We present observations of GRB 060124, the first event for which both the prompt and the afterglow emission could be observed simultaneously and in their entirety by the three Swift instruments and by Konus-Wind. Thanks to these exceptional circumstances, the temporal and spectral properties of the prompt emission could be studied in the optical, X-ray and g

Gilles Pagès

We propose a multi-step Richardson-Romberg extrapolation method for the computation of expectations $E f(X_{_T})$ of a diffusion $(X_t)_{t\in [0,T]}$ when the weak time discretization error induced by the Euler scheme admits an expansion at an order $R\ge 2$. The complexity of the estimator grows as $R^2$ (instead of $2^R$) and its variance is asymptotically

Michael Maziashvili

General relativity and quantum mechanics provide a natural explanation for the existence of dark energy with its observed value and predict its dynamics. Dark energy proves to be necessary for the existence of space-time itself and determines the rate of its stability.

Eduardo Notte-Cuello, Roldao da Rocha, Waldyr A. Rodrigues

In this paper we show that a free electromagnetic field living in Minkowski spacetime generates an effective Weitzenbock or an effective Lorentzian spacetime whose properties aredetermined in details. These results are possible because we found using the Clifford bundle formalism the noticeable result that the energy-momentum densities of a free electromagne

He Zhang

We present a model of the lepton masses and flavor mixing based on the discrete group $S_4 \times Z_2$. In this model, all the charged leptons and neutrinos are assigned to the $3_α$ representation of $S_4$ in the Yamanouchi bases. The charged lepton and neutrino masses are mainly determined by the vacuum expectation value structures of the Higgs fields. A n

Baradhwaj Coleppa, Stefano Di Chiara, Roshan Foadi

A large class of deconstructed Higgsless model is known to satisfy the tree-level experimental bounds on the electroweak precision parameters. In particular, an approximate custodial symmetry insures that the tree-level $ρ$ parameter is exactly one, for arbitrary values of the model parameters, and regardless of fermion delocalization. In this note we expand

J. M. Isidro

We regard classical phase space as a generalised complex manifold and analyse the B-transformation properties of the *-product of functions. The C*-algebra of smooth functions transforms in the expected way, while the C*-algebra of holomorphic functions (when it exists) transforms nontrivially. The B-transformed *-product encodes all the properties of phase-

T. Erdmann, U. S. Schwarz

Cells in multicellular organisms adhere to the extracellular matrix through two-dimensional clusters spanning a size range from very few to thousands of adhesion bonds. For many common receptor-ligand systems, the ligands are tethered to a surface via polymeric spacers with finite binding range, thus adhesion cluster stability crucially depends on receptor-l

S. Capponi, G. Roux, P. Azaria, E. Boulat

The phase diagram of spin-3/2 fermionic cold atoms trapped in a one-dimensional optical lattice is investigated at quarter filling (one atom per site) by means of large-scale numerical simulations. In full agreement with a recent low-energy approach, we find two phases with confined and deconfined Cooper pairs separated by an Ising quantum phase transition.

Jacques Bros, Henri Epstein, Ugo Moschella

We study particle decay in de Sitter space-time as given by first order perturbation theory in an interacting quantum field theory. We show that for fields with masses above a critical mass $m_c$ there is no such thing as particle stability, so that decays forbidden in flat space-time do occur there. The lifetime of such a particle also turns out to be indep

F. Malaspina

In this paper we give the classification of rank 3 vector bundles without &#34;inner&#34; cohomology on a quadric hypersurface \Q_n (n>3) by studying the associated monads.

Isabella Bierenbaum, Dirk Kreimer, Stefan Weinzierl

We solve the linear Dyson Schwinger equation for a massless vertex in Yukawa theory, iterating the first two primitive graphs.

Matteo Guainazzi, Stefano Bianchi

We review the main properties of &#34;warm mirrors&#34; in obscured AGN, and discuss whether the scattering gas could be also responsible for &#34;warm absorbers&#34; commonly observed in unobscured AGN.

Christopher Voll

We introduce a new method to compute explicit formulae for various zeta functions associated to groups and rings. The specific form of these formulae enables us to deduce local functional equations. More precisely, we prove local functional equations for the subring zeta functions associated to rings, the subgroup, conjugacy and representation zeta functions

Carel Faber, Sergey Shadrin, Dimitri Zvonkine

In a series of two preprints, Y.-P. Lee studied relations satisfied by all formal Gromov-Witten potentials, as defined by A. Givental. He called them &#34;universal relations&#34; and studied their connection with tautological relations in the cohomology ring of moduli spaces of stable curves. Building on Y.-P. Lee&#39;s work, we give a simple proof of the f

Stefan Legel, Jürgen König, Guido Burkard, Gerd Schön

We propose schemes for generating spatially-separated spin entanglement in systems of two quantum dots with onsite Coulomb repulsion weakly coupled to a joint electron reservoir. An enhanced probability for the formation of spin entanglement is found in nonequilibrium situations with one extra electron on each dot, either in the transient state after rapid c

Cai-Dian Lü, Yu-Ming Wang, Hao Zou

We study the twist-3 distribution amplitudes for scalar mesons made up of two valence quarks based on QCD sum rules. By choosing the proper correlation functions, we derive the moments of the scalar mesons up to the first two order. Making use of these moments, we then calculate the first two Gegenbauer coefficients for twist-3 distribution amplitudes of sca

Marius Buliga

In this paper we continue the study of dilatation structures, introduced in math.MG/0608536 . A dilatation structure on a metric space is a kind of enhanced self-similarity. By way of examples this is explained here with the help of the middle-thirds Cantor set. Linear and self-similar dilatation structures are introduced and studied on ultrametric spaces, e

Shouchuan Zhang, Min Wu, Hengtai Wang

We obtain the formula computing the number of isomorphic classes of ramification systems with characters over group $S_n$ ($n \not=6$) and their representatives.

Mohammed Benalili, Azzedine Lansari

This paper deals with global asymptotic stability of prolongations of flows induced by specific vector fields and their prolongations. The method used is based on various estimates of the flows.

M. Debbarh, V. Viallon

We establish asymptotic normality for estimators of the additive regression components under random censorship. To build our estimators, we couple the marginal integration method (Newey (1994)) with an initial Inverse Probability of Censoring Weighted estimator of the multivariate censored regression function introduced by Carbonez et al. (1995) and Kohler e

D. Pavlica

Let $f:I\to X$ be a d.c. mapping, where $I\subset \R$ is an open interval and $X$ a Banach space. Let $C_f$ be the set of critical points of $f$. We prove that $f(C_f)$ has zero 1/2-dimensional Hausdorff measure.

Andreas Arvanitoyeorgos, V. V. Dzhepko, YU. G. Nikonorov

A Riemannian manifold $(M,ρ)$ is called Einstein if the metric $ρ$ satisfies the condition $\Ric (ρ)=c\cdot ρ$ for some constant $c$. This paper is devoted to the investigation of $G$-invariant Einstein metrics with additional symmetries, on some homogeneous spaces $G/H$ of classical groups. As a consequence, we obtain new invariant Einstein metrics on some

E. Khan, Nguyen Van Giai, N. Sandulescu

Finite temperature Hartree-Fock-Bogoliubov calculations are performed in Sn isotopes using Skyrme and zero-range, density-dependent pairing interactions. For both stable and very neutron-rich nuclei the critical temperature at which pairing correlations vanish is independent of the volume/surface nature of the pairing interaction. The value of the critical t

J. C. Mottram, J. S. Urquhart, M. G. Hoare, S. L. Lumsden

The Red MSX Source (RMS) survey is a multi-wavelength programme of follow-up observations designed to distinguish between genuine massive young stellar objects (MYSOs) and other embedded or dusty objects, such as ultra compact (UC) HII regions, evolved stars and planetary nebulae (PNe), from a sample of ~2000 MYSOs candidates. These were identified by compar

A. E. Mosaffa, S. Randjbar-Daemi, M. M. Sheikh-Jabbari

Fluctuations of non-Abelian gauge fields in a background magnetic flux contain tachyonic modes and hence the background is unstable. We extend these results to the cases where the background flux is coupled to Einstein gravity and show that the corresponding spherically symmetric geometries, which in the absence of a cosmological constant are of the form of

Giorgio Fagiolo

Many empirical networks display an inherent tendency to cluster, i.e. to form circles of connected nodes. This feature is typically measured by the clustering coefficient (CC). The CC, originally introduced for binary, undirected graphs, has been recently generalized to weighted, undirected networks. Here we extend the CC to the case of (binary and weighted)

A. Rycerz, J. Tworzydlo, C. W. J. Beenakker

We have studied numerically the mesoscopic fluctuations of the conductance of a graphene strip (width W large compared to length L), in an ensemble of samples with different realizations of the random electrostatic potential landscape. For strong disorder (potential fluctuations comparable to the hopping energy), the variance of the conductance approaches th

Wenbing Zhao

In this paper, we present a Byzantine fault tolerant distributed commit protocol for transactions running over untrusted networks. The traditional two-phase commit protocol is enhanced by replicating the coordinator and by running a Byzantine agreement algorithm among the coordinator replicas. Our protocol can tolerate Byzantine faults at the coordinator rep

M. Matsukawa, Y. Yamato, T. Kumagai, R. Suryanarayanan

We report a steplike lattice transformation of single crystalline (La$_{0.4}$Pr$_{0.6}$)$_{1.2}$Sr$_{1.8}$Mn$_{2}$O$_{7}$bilayered manganite accompanied by both magnetization and magnetoresistive jumps, and examine the ultrasharp nature of the field-induced first-order transition from a paramagnetic insulator to a ferromagnetic metal phase accompanied by a h

Tadeusz Lesiak

This paper provides a short review of new states carrying a charm quark(s) which were observed in the recent few years at B factories. The following new particles are discussed: X(3872), Y(3940), X(3940), χ_c^{\prime}(3930), Y(4260), h_c, D_{sJ}, Λ_c(2940), Σ_c(2880), Ξ_{cx}(2980), Ξ_{cx}(3077) and Ω_c^*.

Dietrich Häfner

This work is devoted to the mathematical study of the Hawking effect for fermions in the setting of the collapse of a rotating charged star. We show that an observer who is located far away from the star and at rest with respect to the Boyer Lindquist coordinates observes the emergence of a thermal state when his proper time goes to infinity. We first introd

Hiroshi Kunitomo, Shun&#39;ya Mizoguchi

We study lower-dimensional superstrings in the double-spinor formalism introduced by Aisaka and Kazama. These superstrings can be consistently quantized and are equivalent to the lower-dimensional pure-spinor superstrings proposed by Grassi and Wyllard. The unexpected physical spectrum of the pure-spinor superstrings may thus be regarded as a manifestation o

Junqin Li, Shouchuan Zhang, Hengtai Wang, Min Wu

We obtain the formula computing the number of isomorphic classes of element systems with characters over finite commutative group $G$.

Mustafa Halilsoy, Ozay Gurtug

A method is given which renders indirect detection of strong gravitational waves possible. This is based on the reflection (collision) of a linearly polarized electromagnetic shock wave from (with) a cross polarized impulsive and shock gravitational waves in accordance with the general theory of relativity. This highly non-linear process induces a detectable

Ying-Qiu Gu

To study the coupling system of space-time and Fermions, we need the explicit form of the energy-momentum tensor of spinors. The energy-momentum tensor is closely related to the tetrad frames which cannot be uniquely determined by the metric. This flexibility increases difficulties to derive the exact expression and easily leads to ambiguous results. In this

H. M. Wiseman, S. J. Jones, A. C. Doherty

The concept of steering was introduced by Schrodinger in 1935 as a generalization of the EPR paradox for arbitrary pure bipartite entangled states and arbitrary measurements by one party. Until now, it has never been rigorously defined, so it has not been known (for example) what mixed states are steerable (that is, can be used to exhibit steering). We provi

Nikolai Kochelev

It is shown that instantons can provide an explanation of the strong polarization transfer observed in exclusive hyperon photoproduction at JLab.

Lukasz Szulc, Wojciech Kaminski, Jerzy Lewandowski

The basic idea of the LQC applies to every spatially homogeneous cosmological model, however only the spatially flat (so called $k=0$) case has been understood in detail in the literature thus far. In the closed (so called: k=1) case certain technical difficulties have been the obstacle that stopped the development. In this work the difficulties are overcome

Andrei Khrennikov

In this paper dedicated to the memory of Walter Philipp, we formalize the rules of classical$\to$ quantum correspondence and perform a rigorous mathematical analysis of the assumptions in Bell&#39;s NO-GO arguments.

Stefano Longhi

Bound states in the continuum (BIC) are shown to exist in a single-level Fano-Anderson model with a colored interaction between the discrete state and a tight-binding continuum, which may describe mesoscopic electron or photon transport in a semi-infinite one-dimensional lattice. The existence of BIC is explained in the lattice realization as a boundary effe

Piotr Garbaczewski

Shannon entropy and Fisher information functionals are known to quantify certain information-theoretic properties of continuous probability distributions of various origins. We carry out a systematic study of these functionals, while assuming that the pertinent probability density has a quantum mechanical appearance $ρ\doteq |ψ|^2$, with $ψ\in L^2(R)$. Their

H. J. Zhao, M. L. Du

We study the multi-periodic oscillations in the spontaneous emission rate of an atom in a medium with refractive index n sandwiched between two parallel mirrors. The oscillations are not obvious in the analytical formula for the rate derived based on Fermi&#39;s golden rule but can be extracted using Fourier transforms by varying the system scale while holdi

Daowen Qiu

Recently, Harrow et al. [Phys. Rev. Lett. 92, 187901 (2004)] gave a method for preparing an arbitrary quantum state with high success probability by physically transmitting some qubits, and by consuming a maximally entangled state, together with exhausting some shared random bits. In this paper, we discover that some states are impossible to be perfectly pre

Gary Ruben, David M. Paganin

An analysis is presented of the phase vortices generated in the far field, by an arbitrary arrangement of three monochromatic point sources of complex spherical waves. In contrast with the case of three interfering plane waves, in which an infinitely-extended vortex lattice is generated, the spherical sources generate a finite number of phase vortices. Analy

Christian Raabe, Stefan Scheel, Dirk-Gunnar Welsch

We give a unified approach to macroscopic QED in arbitrary linearly responding media, based on the quite general, nonlocal form of the conductivity tensor as it can be introduced within the framework of linear response theory, and appropriately chosen sets of bosonic variables. The formalism generalizes the quantization schemes that have been developed previ

Emilio Salinas

The sensory-triggered activity of a neuron is typically characterized in terms of a tuning curve, which describes the neuron&#39;s average response as a function of a parameter that characterizes a physical stimulus. What determines the shapes of tuning curves in a neuronal population? Previous theoretical studies and related experiments suggest that many re

Andras Szabo, Erica D. Perryn, Andras Czirok

Vascular and non-vascular cells often form an interconnected network in vitro, similar to the early vascular bed of warm blooded embryos. Our time-lapse recordings show that the network forms by extending sprouts, i.e., multicellular linear segments. To explain the emergence of such structures, we propose a simple model of preferential attraction to stretche

Qinghua Cui, Zhenbao Yu, Enrico O. Purisima, Edwin Wang

MicroRNAs (miRNAs) are endogenous 22-nucleotide RNAs, which suppress gene expression by selectively binding to the 3-noncoding region of specific message RNAs through base-pairing. Given the diversity and abundance of miRNA targets, miRNAs appear to functionally interact with various components of many cellular networks. By analyzing the interactions between

Andrea Fratalocchi, Armando Piccardi, Marco Peccianti, Gaetano Assanto

We demonstrate an original approach to acquire nonlinear control over the angular momentum of a cluster of solitary waves. Our model, derived from a general description of nonlinear energy propagation in dispersive media, shows that the cluster angular momentum can be adjusted by acting on the global energy input into the system. The phenomenon is experiment

Franci Merzel, Fabien Fontaine-Vive, Mark R. Johnson

Computational tools for normal mode analysis, which are widely used in physics and materials science problems, are designed here in a single package called NMscatt (Normal Modes & scattering) that allows arbitrarily large systems to be handled. The package allows inelastic neutron and X-ray scattering observables to be calculated, allowing comparison with ex

Stefano Longhi

It is theoretically shown that storage and time-reversal of light pulses can be achieved in a coupled-resonator optical waveguide by dynamic tuning of the cavity resonances without maintaining the translational invariance of the system. The control exploits the Bloch oscillation motion of a light pulse in presence of a refractive index ramp, and it is theref

Alfredo Iorio

We review the basics of the two most widely used approaches to Lorentz violation - the Stardard Model Extension and Noncommutative Field Theory - and discuss in some detail the example of the modified spectrum of the synchrotron radiation. Motivated by touching upon such a fundamental issue as Lorentz symmetry, we ask three questions: What is behind the sear

I. M. Dremin, A. V. Leonidov

Volatility dynamics of wavelet - filtered stock price time series is studied. Using the universal thresholding method of wavelet filtering and a principle of minimal linear autocorrelation of noise component we find that the quantitative characteristics of volatility dynamics of denoised series are noticeably different from those of the raw data and the nois

Jiajia Cui, Tom G. Mackay

An implementation of the strong-permittivity-fluctuation theory (SPFT) is presented in order to estimate the constitutive parameters of a homogenized composite material (HCM) which is both cubically nonlinear and anisotropic. Unlike conventional approaches to homogenization, the particles which comprise the component material phases are herein assumed to be

John W. Norbury, Lawrence W. Townsend

Total inclusive cross sections for neutral and charged pion production in proton-nucleus and nucleus-nucleus reactions have been calculated and compared to experiment. Nucleon-nucleon theoretical cross sections have been scaled up to nuclear collisions using a scaling factor similar to $(A_PA_T)^{2/3}$, where $A_P$ and $A_T$ are the nucleon numbers of the pr

Zbigniew Chajecki, Mike Lisa

It is increasingly important to understand, in detail, two-pion correlations measured in p+p and d+A collisions. In particular, one wishes to understand the femtoscopic correlations, in order to compare to similar measurements in heavy ion collisions. However, in the low-multiplicity final states of these systems, global conservation laws generate significan

John Arrington, Ingo Sick

The extraction of the strangeness form factors from parity violating elastic electron-proton scattering is sensitive to the electromagnetic form factors at low Q^2. We provide parameterizations for the form factors and uncertainties, including the effects of two-photon exchange corrections to the extracted EM form factors. We study effect of the correlations

P. Konrad, H. Lenske

We investigate short range correlations in nuclear and hypernuclear matter. Self-energies due to short range correlations and their influence on the nucleon and $Λ$-hyperon spectral functions are described in an approach accounting for a realistic treatment of mean-field dynamics and a self-consistently derived quasi-particle interaction. Landau-Migdal theor

L. Tolos, J. Schaffner-Bielich, H. Stoecker

We obtain the D-meson spectral density at finite temperature for the conditions of density and temperature expected at FAIR. We perform a self-consistent coupled-channel calculation taking, as a bare interaction, a separable potential model. The $Λ_c$ (2593) resonance is generated dynamically. We observe that the D-meson spectral density develops a sizeable

K. O. Eyser, I. Alekseev, A. Bravar, G. Bunce

The Relativistic Heavy Ion Collider at Brookhaven National Laboratory provides polarized proton beams for the investigation of the nucleon spin structure. For polarimetry, carbon-proton and proton-proton scattering is used in the Coulomb nuclear interference region at small momentum transfer ($-t$). Fast polarization measurements of each beam are carried out

Maria Yurova

In this paper we investigate the application of Zakharov - Shabat dressing method to (2+1) - dimensional long wave - short wave resonance interaction equation (LSRI). Using this method we can construct the exact N - soliton solution of this equation depending on arbitrary constants. It contains both solutions which don&#39;t decay along N different direction

Branko Dragovich, Andrei Khrennikov, Dusan Mihajlovic

Using an adelic approach we simultaneously consider real and p-adic aspects of dynamical systems whose states are mapped by linear fractional transformations isomorphic to some subgroups of GL (2, Q), SL (2, Q) and SL (2, Z) groups. In particular, we investigate behavior of these adelic systems when fixed points are rational. It is shown that any of these ra

Mushfiq Ahmad

We have defined slowness (or reciprocal velocity, corresponding to velocity v) as cc/v, where c is the speed of light. It is observed that the relative velocity remains invariant if the velocities are replaced by corresponding slownesses i.e. relative motion in one dimension is reciprocal symmetric. Reciprocity operation, which converts a velocity to the cor

Dimitrios Cheliotis

For a diffusion X_t in a one-dimensional Wiener medium W, it is known that there is a certain process b_x(W) that depends only on the environment W, so that X_t-b_{logt}(W) converges in distribution as t goes to infinity. We prove that, modulo a relatively small time change, the process {b_x(W):x>0}is followed closely by the process {F_X(e^x): x>0}, with F_X

Aaron Naber

The Bakry-Emery Ricci tensor of a metric-measure space (M,g,e^{-f}dv_{g}) plays an important role in both geometric measure theory and the study of Hamilton&#39;s Ricci flow. Under a uniform positivity condition on this tensor and with bounded Ricci curvature we show the underlying space has finite f-volume. As a consequence such manifolds, including shrinki

Miroslav Pavlović, Kehe Zhu

We obtain several new characterizations for the standard weighted Bergman spaces $A^p_α$ on the unit ball of $\cn$ in terms of the radial derivative, the holomorphic gradient, and the invariant gradient.

Satyan L. Devadoss

Given any finite graph, we offer a simple realization of the graph-associahedron polytope using integer coordinates.

Yuan Xu

An explicit family of polynomials on the unit ball $B^d$ of $\RR^d$ is constructed, so that it is an orthonormal family with respect to the inner product $$ < f,g > = ρ\int_{B^d}\nabla f(x)\cdot \nabla g(x) dx + \CL (fg), $$ where $ρ>0$, $\nabla$ is the gradient, and $\CL(fg)$ is either the inner product on the sphere $S^{d-1}$ or $f(0)g(0)$.

Riviere Tristan

We found a new formulation to the Euler-Lagrange equation of the Willmore functional for immersed surfaces in ${\R}^m$. This new formulation of Willmore equation appears to be of divergence form, moreover, the non-linearities are made of jacobians. Additionally to that, if $\bH$ denotes the mean curvature vector of the surface, this new form writes ${\mathca

János Kollár

The aim of this paper is to study compact 5--manifolds which carry a positive Sasakian structure. Strong restrictions are derived for the integral homology groups. In some cases, all positive Sasakian structures are classified. A key step is to study log Del Pezzo surfaces whose boundary divisor contains positive genus curves.

Christoph Wockel

In this paper we describe how one can obtain Lie group structures on the group of (vertical) bundle automorphisms for a locally convex principal bundle P over the compact manifold M. This is done by first considering Lie group structures on the group of vertical bundle automorphisms Gau(P). Then the full automorphism group Aut(P) is considered as an extensio

Antoine Ducros

We propose here a transcendantal proof of the coherence of the higher direct images of a coherent sheaf by a proper morphism of algebraic varieties, which does not use Chow&#39;s lemma nor any projective method. The main tool here are comparison with coherent cohomology of a (Berkovich) analytic space over a trivially valued field, and Kiehls&#39; theorem ab

Ellen Shiting Bao, YanYan Li, Biao Yin

This paper concerns optimal gradient estimates of solutions for the perfect conductivity problem with closely spaced interfacial boundaries. The problem arises from composite material. Our estimates exhibit different blow up rates of the gradients, as the distance between the inclusions goes to zero, in dimensions n=2, n=3 and n\ge 4, which become higher as

Maria Giovanna Mora, Stefan Müller

A convergence result is proved for the equilibrium configurations of a three-dimensional thin elastic beam, as the diameter h of the cross-section goes to zero. More precisely, we show that stationary points of the nonlinear elastic functional E^h, whose energies (per unit cross-section) are bounded by Ch^2, converge to stationary points of the Gamma-limit o

Rémi Carles

We review some results concerning the semi-classical limit for the nonlinear Schrodinger equation, with or without an external potential. We consider initial data which are either of the WKB type, or very concentrated as the semi-classical parameter goes to zero. We sketch the techniques used according to various frameworks, and point out some open problems.

Bo&#39;az Klartag, Gady Kozma

Let N > n, and denote by K the convex hull of N independent standard gaussian random vectors in an n-dimensional Euclidean space. We prove that with high probability, the isotropic constant of K is bounded by a universal constant. Thus we verify the hyperplane conjecture for the class of gaussian random polytopes.

Priska Jahnke, Thomas Peternell

We classify almost del Pezzo manifolds in arbitrary dimension n, i.e., projective manifolds X with big and nef anticanonical bundle -K_X, such that -K_X is divisible by n-1.

Bertrand Banos

In this lecture delivered at the Integrable and Quantum Field Theory at Peyresq sixth meeting, we review the Lychagin&#39;s Monge-Ampere operators theory and exhibit the link it establishes between the classical problem of local equivalence for non linear partial differential equations and the problem of integrability of some geometrical structures.

Binod Kumar Sahoo, N. S. Narasimha Sastry

We show that, if the representation group $R$ of a slim dense near hexagon $S$ is non-abelian, then $R$ is of exponent 4 and $|R|=2^β$, $1+NPdim(S)\leq β\leq 1+dimV(S)$, where $NPdim(S)$ is the near polygon embedding dimension of $S$ and $dimV(S)$ is the dimension of the universal representation module $V(S)$ of $S$. Further, if $β=1+NPdim(S)$, then $R$ is a

F. Malaspina

We improve Ottaviani&#39;s splitting criterion for vector bundles on a quadric hypersurface and obtain the equivalent of the result by Rao, Mohan Kumar and Peterson. Then we give the classification of rank 2 bundles without &#34;inner&#34; cohomology on Q_n (n>3). It surprisingly exactly agrees with the classification by Ancona, Peternell and Wisniewski of r

Peter Polacik, Vladimir Sverak

We show that the 1d viscous Burgers equation considered for complex valued functions develops finite-time singularities from compactly supported smooth data. By means of the Cole-Hopf transformation, the singularities of the solutions are related to zeros of complex-valued solutions of the heat equation. We prove that such zeros are isolated if they are not

Monica Manjarin

We construct some families of complex structures on compact manifolds by means of normal almost contact structures (nacs) so that each complex manifold in the family has a non-singular holomorphic flow. These families include as particular cases the Hopf and Calabi-Eckmann manifolds and the complex structures on the product of two normal almost contact manif

Jae-Hyun Yang

We give a geometrical construction of the canonical automorphic factor for the Jacobi group and construct new vector valued modular forms from Jacobi forms by differentiating them with respect to toroidal variables and then evaluating at zero.

Norman J. Wildberger

By recasting metrical geometry in a purely algebraic setting, both Euclidean and non-Euclidean geometries can be studied over a general field with an arbitrary quadratic form. Both an affine and a projective version of this new theory are introduced here, and the main formulas extend those of rational trigonometry in the plane. This gives a unified, computat

Benjamin Steinberg

We show that if $\mathbf H$ is a Fitting pseudovariety of groups and $\mathbf V$ is a local pseudovariety of monoids, then $\mathbf {LH}m \mathbf V$ is local if either $\mathbf V$ contains the six element Brandt monoid, or $\mathbf H$ is a non-trivial pseudovariety of groups closed under extension.

Karsten Henckell, John Rhodes, Benjamin Steinberg

We give a short proof, using profinite techniques, that idempotent pointlikes, stable pairs and triples are decidable for the pseudovariety of aperiodic monoids. Stable pairs are also described for the pseudovariety of all finite monoids.

Brian J. Day

This article represents a preliminary attempt to link Kan extensions, and some of their further developments, to Fourier theory and quantum algebra through *-autonomous monoidal categories and related structures.

James Hirschorn

Some general properties of abstract relations are closely examined. These include generalizations of linearity, and properties based on `pinning&#39; an inequality by a pair of families of endomorphisms.To each property we try to associate a canonical definition of an augmentation (or diminishment) that augments (or diminishes) any given relation to one sati

Albrecht Böttcher, Alexei Karlovich, Bernd Silbermann

We give a survey on generalized Krein algebras $K_{p,q}^{α,β}$ and their applications to Toeplitz determinants. Our methods originated in a paper by Mark Krein of 1966, where he showed that $K_{2,2}^{1/2,1/2}$ is a Banach algebra. Subsequently, Widom proved the strong Szegő limit theorem for block Toeplitz determinants with symbols in $(K_{2,2}^{1/2,1/2})_{N

Alan W. Reid, Genevieve S. Walsh

We show that a hyperbolic 2-bridge knot complement is the unique knot complement in its commensurability class. We also discuss constructions of commensurable hyperbolic knot complements and put forth a conjecture on the number of hyperbolic knot complements in a commensurability class.