November 2005 arXiv papers — page 41

H. Hoekstra, Y. Mellier, L. van Waerbeke, E. Semboloni

We present the first measurements of the weak gravitational lensing signal induced by the large scale mass distribution from data obtained as part of the ongoing Canada-France-Hawaii Telescope Legacy Survey (CFHTLS). The data used in this analysis are from the Wide Synoptic Survey, which aims to image ~170 square degree in five filters. We have analysed ~22

Malcolm Fairbairn

The lens candidate CSL-1 has been interpreted as evidence for a cosmic string. Here we test the hypothesis that the lensing comes from a tidally disrupted dark matter halo. We calculate the mass-density relationship that one would expect from structure formation theory and come to the conclusion that in order to explain the lensing using dark matter, the hal

N. E. Zein, S. Y. Savrasov, G. Kotliar

Using a novel self-consistent implementation of Hedin's GW perturbation theory we calculate space and energy dependent self-energy for a number of materials. We find it to be local in real space and rapidly convergent on second-- to third-- nearest neighbors. Corrections beyond GW are evaluated and shown to be completely localized within a single unit ce

C. E. Pearson, D. R. Leibrandt, W. S. Bakr, W. J. Mallard

Chiaverini et al. [Quant. Inf. Comput. 5, 419 (2005)] recently suggested a linear Paul trap geometry for ion trap quantum computation that places all of the electrodes in a plane. Such planar ion traps are compatible with modern semiconductor fabrication techniques and can be scaled to make compact, many zone traps. In this paper we present an experimental r

E. Semboloni, Y. Mellier, L. van Waerbeke, H. Hoekstra

We present the first cosmic shear measurements obtained from the T0001 release of the Canada-France-Hawaii Telescope Legacy Survey. The data set covers three uncorrelated patches (D1, D3 and D4) of one square degree each observed in u*, g', r', i' and z' bands, out to i'=25.5. The depth and the multicolored observations done in deep field

G. David Forney,, Markus Grassl, Saikat Guha

Rate-(n-2)/n unrestricted and CSS-type quantum convolutional codes with up to 4096 states and minimum distances up to 10 are constructed as stabilizer codes from classical self-orthogonal rate-1/n F_4-linear and binary linear convolutional codes, respectively. These codes generally have higher rate and less decoding complexity than comparable quantum block c

Amarjit Soni, Denis A. Suprun

U-spin multiplet approach is applied to the full set of charmless hadronic B+/- --> M0 M+/- decays for the purpose of precise extraction of the unitarity angle gamma. Each of the four data sets, P0 P+/-, P0 V+/-, V0 P+/- and V0 V+/-, with P = pseudoscalar and V = vector, can be used to yield a precise value of gamma. The crucial advantage of this method over

S. A. Cannas, M. F. Michelon, D. A. Stariolo, F. A. Tamarit

We study the critical properties of a two--dimensional Ising model with competing ferromagnetic exchange and dipolar interactions, which models an ultra-thin magnetic film with high out--of--plane anisotropy in the monolayer limit. We present numerical evidence showing that two different scenarios appear in the model for different values of the exchange to d

Ruy Exel

Let G be a group and let P be a subsemigroup of G. In order to describe the crossed product of a C*-algebra A by an action of P by unital endomorphisms we find that we must extend the action to the whole group G. This extension fits into a broader notion of "interaction groups" which consists of an assignment of a positive operator V_g on A for each

Zur Izhakian

This paper introduces the foundations of the polynomial algebra and basic structures for algebraic geometry over the extended tropical semiring. Our development, which includes the tropical version for the fundamental theorem of algebra, leads to the reduced polynomial semiring -- a structure that provides a basis for developing a tropical analogue to the cl

Fernando Cukierman, Jorge Vitorio Pereira

We show that the set of singular holomorphic foliations of the projective spaces with split tangent sheaf and with good singular set is open in the space of holomorphic foliations. As applications we present a generalization of a result by Camacho-Lins Neto about linear pull-back foliations, we give a criterium for the rigidity of $\mathcal L$-foliations of

Didier Piau

We show that the mean inverse populations of nondecreasing, square integrable, continuous-time branching processes decrease to zero like the inverse of their mean population if and only if the initial population $k$ is greater than a first threshold $m_1\ge1$. If, furthermore, $k$ is greater than a second threshold $m_2\ge m_1$, the normalized mean inverse p

W. Hollik, S. Penaranda, M. Vogt

Flavour changing effects originating from the exchange of scalar particles in the processes e^+ e^- -> H b \bar{s}, H \bar{b} s, with H = h^0, H^0, A^0, are investigated in the Minimal Supersymmetric Standard Model with non-minimal flavour violation at the one-loop level. The dominating SUSY-QCD contributions with squark--gluino loops are calculated and disc

J. R. Cortes, J. D. P. Kenney, E. Hardy

We present a detailed study of the peculiar HI-deficient Virgo cluster spiral galaxies NGC 4064 and NGC 4424, using $^{12}$CO 1-0 interferometry, optical imaging and integral-field spectroscopic observations, in order to learn what type of environmental interactions have afected these galaxies. Optical imaging reveals that NGC 4424 has a strongly disturbed s

S. Derkachov, D. Karakhanyan, R. Kirschner

We construct Baxter operators as generalized transfer matrices being traces of products of generic $R$ matrices. The latter are shown to factorize into simpler operators allowing for explicit expressions in terms of functions of a Weyl pair of basic operators. These explicit expressions are the basis for explicit expression for Baxter Q-operators and for inv

Dmytro Gavinsky, Julia Kempe, Oded Regev, Ronald de Wolf

We consider the problem of bounded-error quantum state identification: given either state \alpha_0 or state \alpha_1, we are required to output `0', `1' or `?' ("don't know"), such that conditioned on outputting `0' or `1', our guess is correct with high probability. The goal is to maximize the probability of not outputting `?'. We prove a direct product the

A. Kadeer, J. G. Körner, U. Moosbrugger

Using the helicity method we derive complete formulas for the joint angular decay distributions occurring in semileptonic hyperon decays including lepton mass and polarization effects. Compared to the traditional covariant calculation the helicity method allows one to organize the calculation of the angular decay distributions in a very compact and efficient

Sho Tanaka

Motivated by the recent proposition by Buniy, Hsu and Zee with respect to discrete space-time and finite spatial degrees of freedom of our physical world with a short- and a long-distance scales, $l_P$ and $L,$ we reconsider the Lorentz-covariant Yang's quantized space-time algebra (YSTA), which is intrinsically equipped with such two kinds of scale para

H. Arodz, P. Klimas, T. Tyranowski

We investigate a (1+1)-dimensional nonlinear field theoretic model with the field potential $V(ϕ)| = |ϕ|.$ It can be obtained as the universal small amplitude limit in a class of models with potentials which are symmetrically V-shaped at their minima, or as a continuum limit of certain mechanical system with infinite number of degrees of freedom. The model h

Iwo Bialynicki-Birula, Zofia Bialynicka-Birula

All beams of electromagnetic radiation are made of photons. Therefore, it is important to find a precise relationship between the classical properties of the beam and the quantum characteristics of the photons that make a particular beam. It is shown that this relationship is best expressed in terms of the Riemann-Silberstein vector -- a complex combination

Asantha Cooray, Alessandro Melchiorri

The cross-correlation between cosmic microwave background (CMB) temperature anisotropies and the large scale structure (LSS) traced by the galaxy distribution, or sources at different wavelengths, is now well known. This correlation results from the integrated Sachs-Wolfe (ISW) effect in CMB anisotropies generated at late times due to the dark energy compone

H. D. Cornean, J. Dereziński, P. Ziń

We consider second quantized homogeneous Bose gas in a large cubic box with periodic boundary conditions, at zero temperature. We discuss the energy-momentum spectrum of the Bose gas and its physical significance. We review various rigorous and heuristic results as well as open conjectures about its properties. Our main aim is to convince the readers, includ

M. Oulne

An approximate analytical solution of the Thomas-Fermi equation for neutral atoms is obtained, using the Ritz variational method, which reproduces accurately the numerical solution, in the range $0\leq x\leq50$, and its derivative at $x=0$. The proposed solution is used to calculate the total ionization energies of heavy atoms. The obtained results are in go

M. C. Bergère

For a restricted class of potentials (harmonic+Gaussian potentials), we express the resolvent integral for the correlation functions of simple traces of powers of complex matrices of size $N$, in term of a determinant; this determinant is function of four kernels constructed from the orthogonal polynomials corresponding to the potential and from their Cauchy

Cédric Bonnafé

Let $p$ be a prime number and let $n$ be a non-zero natural number. We compute the descending Loewy series of the algebra $R\_n/pR\_n$, where $R\_n$ denotes the ring of virtual ordinary characters of the symmetric group $S\_n$.

I. Katkov

A selection of recent results on heavy quark production at the HERA collider by the H1 and ZEUS collaborations are presented with a focus on charmonium production in DIS, charm fragmentation and beauty production.

Stoytcho S. Yazadjiev

We derive new rotating, non-asymptotically flat black ring solutions in five-dimensional Einstein-Maxwell-dilaton gravity with dilaton coupling constant $α=\sqrt{8/3}$ which arises from a six-dimensional Kaluza-Klein theory. As a limiting case we also find new rotating, non-asymptotically flat five-dimensional black holes. The solutions are analyzed and the

J. H. Field

The force due to electromagnetic induction on a test charge is calculated in different reference frames. The Faraday-Lenz Law and different formulae for the fields of a uniformly moving charge are used. The classical Heaviside formula for the electric field of a moving charge predicts that, for the particular spatial configuration considered, the inductive f

Pradip Roy, Abhee K. Dutt-Mazumder, Jan-e Alam

Average energy loss of light quarks has been calculated in a two stage equilibrium scenario where the quarks are executing Brownian motion in a gluonic heat bath. The evolution of the quark $p_T$ spectra is studied by solving Fokker-Planck equation in an expanding plasma. Results are finally compared with experimentally measured pion $p_T$ spectrum at RHIC.

Y. Pinchover, K. Tintarev

Let $Ω$ be a domain in $\mathbb{R}^d$, $d\geq 2$, and $1<p<\infty$. Fix $V\in L_{\mathrm{loc}}^\infty(Ω)$. Consider the functional $Q$ and its Gâteaux derivative $Q^\prime$ given by $$Q(u):=\int_Ω(|\nabla u|^p+V|u|^p)\dx, \frac{1}{p}Q^\prime (u):=-\nabla\cdot(|\nabla u|^{p-2}\nabla u)+V|u|^{p-2}u.$$ If $Q\ge 0$ on $C_0^{\infty}(Ω)$, then either there is a po

Katarzyna Grabowska, Pawel Urbanski

A frame independent formulation of analytical mechanics in the Newtonian space-time is presented The differential geometry of affine values i.e., the differential geometry in which affine bundles replace vector bundles and sections of one dimensional affine bundles replace functions on manifolds, is uded. Lagragian and hamiltonian generating objects, togethe

Dmitri Maslov, D. Michael Miller

A breadth-first search method for determining optimal 3-line circuits composed of quantum NOT, CNOT, controlled-V and controlled-V+ (NCV) gates is introduced. Results are presented for simple gate count and for technology motivated cost metrics. The optimal NCV circuits are also compared to NCV circuits derived from optimal NOT, CNOT and Toffoli (NCT) gate c

José Ignacio Alvarez-Hamelin, Luca Dall&#39;Asta, Alain Barrat, Alessandro Vespignani

We consider the $k$-core decomposition of network models and Internet graphs at the autonomous system (AS) level. The $k$-core analysis allows to characterize networks beyond the degree distribution and uncover structural properties and hierarchies due to the specific architecture of the system. We compare the $k$-core structure obtained for AS graphs with t

Tadeusz Lesiak

The properties of three new particles X(3872), Y(3940) and Z(3931), recently dicovered by the Belle collaboration, are briefly reviewed. Negative results of the search for the pentaquark $\Theta(1540)^+$ are also presented

Shin Ishida

Several years ago we have proposed a manifestly covariant $\tilde{U}(12)_{SF}$-classification scheme of hadrons, which maintains the successful $SU(6)_{SF}\otimes O(3)_{L}$ framework in Non-Relativistic Quark Model and is also reconcilable with the mechanism of Spontaneously-Broken Chiral Symmetry in Relativistic Field Theoretical Models. The essential point

Baojiu Li, Ming-Chung Chu

The successful prediction of light element abundances from Big Bang Nucleosynthesis has been a pillar of the standard model of Cosmology. Because many of the relevant reaction rates are sensitive to the values of fundamental constants, such as the fine structure constant and the strong coupling constant, BBN is a useful tool to probe and to put constraints o

Alexander I. Bufetov

The logarithmic asymptotics for the growth of the number of periodic orbits, such that the norm of the corresponding renormalization matrix does not exceed a given constant, is computed for the Teichmueller flow on Veech&#39;s moduli space of zippered rectangles. The rate is equal to the entropy of the flow with respect to the absolutely continuous invariant

Tohya Hiroshima

We prove multiplicativity of maximal output $p$ norm of classical noise channels and thermal noise channels of arbitrary modes for all $p>1$ under the assumption that the input signal states are Gaussian states. As a direct consequence, we also show the additivity of the minimal output entropy and that of the energy-constrained Holevo capacity for those Gaus

M. Stengel, N. A. Spaldin

We present a novel technique for calculating the dielectric response of metal/insulator heterostructures. This scheme allows, for the first time, the fully first-principles calculation of the microscopic properties of thin-film capacitors at finite bias potential. The method can be readily applied to pure insulators, where it provides an interesting alternat

Jean Goubault-Larrecq, Slawomir Lasota, David Nowak

Logical relations and their generalizations are a fundamental tool in proving properties of lambda-calculi, e.g., yielding sound principles for observational equivalence. We propose a natural notion of logical relations able to deal with the monadic types of Moggi&#39;s computational lambda-calculus. The treatment is categorical, and is based on notions of s

S. D. Jenkins, D. N. Matsukevich, T. Chaneliere, A. Kuzmich

We investigate the dynamics of dark-state polaritons in an atomic ensemble with ground-state degeneracy. A signal light pulse may be stored and retrieved from the atomic sample by adiabatic variation of the amplitude of a control field. During the storage process, a magnetic field causes rotation of the atomic hyperfine coherences, leading to collapses and r

D. N. Matsukevich, T. Chaneliere, S. D. Jenkins, S. -Y. Lan

By time-dependent variation of a control field, both coherent and single photon states of light are stored in, and retrieved from, a cold atomic gas. The efficiency of retrieval is studied as a function of the storage time in an applied magnetic field. A series of collapses and revivals is observed, in very good agreement with theoretical predictions. The ob

T. Chaneliere, D. N. Matsukevich, S. D. Jenkins, S. -Y. Lan

An elementary quantum network operation involves storing a qubit state in an atomic quantum memory node, and then retrieving and transporting the information through a single photon excitation to a remote quantum memory node for further storage or analysis. Implementations of quantum network operations are thus conditioned on the ability to realize such matt

D. N. Matsukevich, T. Chaneliere, S. D. Jenkins, S. -Y. Lan

We report observations of entanglement of two remote atomic qubits, achieved by generating an entangled state of an atomic qubit and a single photon at Site A, transmitting the photon to Site B in an adjacent laboratory through an optical fiber, and converting the photon into an atomic qubit. Entanglement of the two remote atomic qubits is inferred by perfor

O. V. Zhirov, D. L. Shepelyansky

Using the methods of quantum trajectories we study effects of dissipative decoherence on the accuracy of the Grover quantum search algorithm. The dependence on the number of qubits and dissipation rate are determined and tested numerically with up to 16 qubits. As a result, our numerical and analytical studies give the universal law for decay of fidelity and

J. F. Corney, P. D. Drummond

We formulate a general multi-mode Gaussian operator basis for fermions, to enable a positive phase-space representation of correlated Fermi states. The Gaussian basis extends existing bosonic phase-space methods to Fermi systems and thus enables first-principles dynamical or equilibrium calculations in quantum many-body Fermi systems. We prove the completene

Michael Brown-Hayes, Diego A. R. Dalvit, Francisco D. Mazzitelli, Woo-Joong Kim

We report on a proposal aimed at measuring the Casimir force in a cylinder-plane configuration. The Casimir force is evaluated including corrections due to finite parallelism, conductivity, and temperature. The range of validity of the proximity force approximation is also discussed. An apparatus to test the feasibility of a precision measurement in this con

Cristopher Moore, Alexander Russell

This article has been withdrawn by the authors.

Yumi Nakajima, Yasuhito Kawano, Hiroshi Sekigawa

We provide a new algorithm that translates a unitary matrix into a quantum circuit according to the G=KAK theorem in Lie group theory. With our algorithm, any matrix decomposition corresponding to type-AIII KAK decompositions can be derived according to the given Cartan involution. Our algorithm contains, as its special cases, Cosine-Sine decomposition (CSD)

S. Pigolotti, A. Flammini, M. Marsili, A. Maritan

Interpretation of empirical results based on a taxa&#39;s lifetime distribution shows apparently conflicting results. Species&#39; lifetime is reported to be exponentially distributed, whereas higher order taxa, such as families or genera, follow a broader distribution, compatible with power law decay. We show that both these evidences are consistent with a

N. H. Ravindranath, N. V. Joshi, R. Sukumar, A. Saxena

Global assessments have shown that future climate change is likely to significantly impact forest ecosystems. The present study makes an assessment of the impact of projected climate change on forest ecosystems in India. This assessment is based on climate projections of Regional Climate Model of the Hadley Centre (HadRM3) using the A2 (740 ppm CO2) and B2 (

Douglas A. Galbi

The frequency distribution of personal given names offers important evidence about the information economy. This paper presents data on the popularity of the most frequent personal given names (first names) in England and Wales over the past millennium. The popularity of a name is its frequency relative to the total name instances sampled. The data show that

Kunming Xu

Euclidean geometry does not characterize dynamic electronic orbitals satisfactorily for even a single electron in a hydrogen atom is a formidable mathematical task with the Schrodinger equation. Here the author puts forward a new spacetime concept that regards space and time as two orthogonal, symmetric and complementary quantities. They are inherent physica

Dirk Helbing, Stefan Lämmer, Jean-Patrick Lebacque

We present a fluid-dynamic model for the simulation of urban traffic networks with road sections of different lengths and capacities. The model allows one to efficiently simulate the transitions between free and congested traffic, taking into account congestion-responsive traffic assignment and adaptive traffic control. We observe dynamic traffic patterns wh

R Mingesz, Z Gingl, P Makra

On the basis of our mixed-signal simulations we report significant stochastic resonance induced input-output signal improvement in the double-well system for aperiodic input types. We used a pulse train with randomised pulse locations and a band-limited noise with low cut-off frequency as input signals, and applied a cross-spectral measure to quantify their

A. P. Potylitsyn, R. O. Rezaev

In the article the transition radiation from a relativistic charge crossing a finite radius paraboloid target with taking into account the pre-wave zone effect is considered. It is shown that in this case the radiation cone narrowing occurs in contrast with the transition radiation from the flat target if the detector is situated at the distance, which is sm

Stefanos Dris, Markus Axer, Costas Foudas, Karl Gill

The feasibility of achieving faster data transmission using advanced digital modulation techniques over the current CMS Tracker analog optical link is explored. The spectral efficiency of Quadrature Amplitude Modulation -Orthogonal Frequency Division Multiplexing (QAM-OFDM) makes it an attractive option for a future implementation of the readout link. An ana

F. Nessi-Tedaldi

Scintillating crystals are used for calorimetry in several high-energy physics experiments. For many of them, performance has to be ensured in very difficult operating conditions, like a high radiation environment and large particle fluxes, which place constraints on response and readout time. An overview is presented of the knowledge reached up to date, and

P. Piot, Y. -E Sun, K. -J. Kim

The generation of a flat electron beam directly from a photoinjector is an attractive alternative to the electron damping ring as envisioned for linear colliders. It also has potential applications to light sources such as the generation of ultra-short x-ray pulses or Smith-Purcell free electron lasers. In this Letter, we report on the experimental generatio

Jozsef Garai, Alexandre Laugier

In solid phase the pressure correlates to the elastic related volume change while the temperature to the thermal related volume change. These volume changes are not compatible with the exception of constant volume condition when the expanded volume converts completely compressed volume. Separating the thermal and elastic related volume changes the work funct

A. Nogga, C. Hanhart

We give a prove of evidence that the original power counting by Weinberg can be applied to estimate the contributions of the operators contributing to the pi-deuteron scattering length. As a consequence, pi-deuteron observables can be used to extract neutron amplitudes--in case of pi-deuteron scattering this means that the pi-neutron scattering length can be

Scott Pratt, Daniel Schindel

Two-particle correlations from RHIC have provided a surprising snapshot of the final state at RHIC. In this talk I discuss the nature of the HBT puzzle and attempt to delineate several factors which might ultimately resolve the issue.

Scott Pratt

Using optical model calculations it has recently been shown that refractive phenomena from the collective mean field can significantly alter the sizes inferred from two-pion correlations. We demonstrate that such effects can be accounted for in classical calculations if mean field effects are included.

Scott Pratt

The ability to measure characteristics of source shapes using non-identical particle correlations is discussed. Both strong-interaction induced and Coulomb induced correlations are shown to provide sensitivity to source shapes. By decomposing correlation functions with spherical or Cartesian harmonics, details of the shapes can be especially well isolated.

Wolfgang Bauer, Scott Pratt, Brandon Alleman

We show that Zipf&#39;s Law for the largest clusters is not valid in an exact sense at the critical point of the fragmentation phase transition, contrary to previous claims. Instead, the extracted distributions of the largest clusters reflects the choice of universality class through the value of the critical exponent tau.

I. V. Simenog, B. E. Grinyuk, Yu. M. Bidasyuk

A theoretical possibility is shown for the bound state of a tetraneutron to exist in the case of the proposed neutron-neutron potentials in the singlet state with two attractive wells separated by a repulsive barrier. The anomalous behaviours are revealed for the calculated size, density distribution, and pair correlation functions of a hypothetical tetraneu

C. Gaulard, G. Audi, C. Bachelet, D. Lunney

The minuteness of the nuclear binding energy requires that mass measurements be highly precise and accurate. Here we report on new measurements $^{29-33}$Mg and $^{26}$Na performed with the {\sc Mistral} mass spectrometer at {\sc Cern}&#39;s {\sc Isolde} facility. Since mass measurements are prone to systematic errors, considerable effort has been devoted to

Manuel F. Rañada

The properties of a system of n = 3 coupled oscillators with linear terms in the velocities (magnetic terms) depending in two parameters are studied. We proved the existence of a bi-Hamiltonian structure arising from a non-symplectic symmetry, as well the existence of master symmetries and additional integrals of motion (weak superintegrability) for certain

T. S. Lo, Victor S. L&#39;vov, Itamar Procaccia

Drag reduction in stationary turbulent flows by bubbles is sensitive to the dynamics of bubble oscillations. Without this dynamical effect the bubbles only renormalize the fluid density and viscosity, an effect that by itself can only lead to a small percentage of drag reduction. We show in this paper that the dynamics of bubbles and their effect on the comp

Sergey A. Denisov

We prove that 3-dimensional Schrodinger operator with slowly decaying sparse potential has an a.c. spectrum that fills positive half-line. A new kind of WKB asymptotics for Green&#39;s function is found. The absense of positive eigenvalues is established as well.

Xiaoda Ji, Decio Levi, Matteo Petrera

We expand a discrete--time lattice sine--Gordon equation on multiple lattices and obtain the partial difference equation which governs its far field behaviour. Such reduction allow us to obtain a new completely discrete nonlinear Schröedinger (NLS) type equation.

Brian Hartwig, Paul Terwilliger

Let $K$ denote a field with characteristic 0 and let $T$ denote an indeterminate. We give a presentation for the three-point loop algebra $\mathfrak{sl}_2 \otimes K\lbrack T, T^{-1},(T-1)^{-1}\rbrack$ via generators and relations. This presentation displays $S_4$-symmetry. Using this presentation we obtain a decomposition of the above loop algebra into a dir

Laszlo Erdos

We present a review on the recent developments concerning rigorous mathematical results on Schrödinger operators with magnetic fields. This paper is dedicated to the sixtieth birthday of Barry Simon.

A. Elgart, G. M. Graf, J. H. Schenker

We consider the edge and bulk conductances for 2D quantum Hall systems in which the Fermi energy falls in a band where bulk states are localized. We show that the resulting quantities are equal, when appropriately defined. An appropriate definition of the edge conductance may be obtained through a suitable time averaging procedure or by including a contribut

John K. Hunter

We prove short-time existence of smooth solutions for a class of nonlinear, and in general spatially nonlocal, Hamiltonian evolution equations that describe the self-interaction of weakly nonlinear scale-invariant waves. These equations include ones that describe weakly nonlinear hyperbolic surface waves, such as nonlinear Rayleigh waves

Giuseppe Ali, John K. Hunter

We derive an asymptotic solution of the vacuum Einstein equations that describes the propagation and diffraction of a localized, large-amplitude, rapidly-varying gravitational wave. We compare and contrast the resulting theory of strongly nonlinear geometrical optics for the Einstein equations with nonlinear geometrical optics theories for variational wave e

Christoph Wockel

In this paper we present another notion of a smooth manifold with corners and relate it to the commonly used concept in the literature. Afterwards we introduce complex manifolds with corners and show that if $M$ is a compact (respectively complex) manifold with corners and $K$ is a smooth (respectively complex) Lie group, then $C^{\infty}(M,K)$ (respectively

Idris Assani

We study the pointwise convergence of some weighted averages linked to averages along cubes. We show that if $(X,\mathcal{B},μ, T_i)$ are not necessarily commuting measure preserving systems on the same finite measure space and if $f_i,$ $1\leq i\leq 6$ are bounded functions then the averages $$\frac{1}{N^3}\sum_{n, m, p=1}^N f_1(T_1^nx) f_2(T_2^mx) f_3(T_3^

Halvard Fausk, Daniel C. Isaksen

We introduce a notion of a filtered model structure and use this notion to produce various model structures on pro-categories. This framework generalizes several known examples. We give several examples, including a homotopy theory for $G$-spaces, where $G$ is a pro-finite group. The class of weak equivalences is an approximation to the class of underlying w

Fu Liu

The original motivation for study for hook length polynomials was to find a combinatorial proof for a hook length formula for binary trees given by Postnikov, as well as a proof for a hook length polynomial formula conjectured by Lascoux. In this paper, we define the hook length polynomial for plane forests of a given degree sequence type and show it can be

Eitan Tadmor, Terence Tao

We prove new velocity averaging results for second-order multidimensional equations of the general form, $\op(\nabla_x,v)f(x,v)=g(x,v)$ where $\op(\nabla_x,v):=\bba(v)\cdot\nabla_x-\nabla_x^\top\cdot\bbb(v)\nabla_x$. These results quantify the Sobolev regularity of the averages, $\int_vf(x,v)ϕ(v)dv$, in terms of the non-degeneracy of the set $\{v: |\op(\ixi,

Alexis Devulder

We study a one-dimensional diffusion process in a drifted Brownian potential. We characterize the upper functions of its hitting times in the sense of Paul Lévy, and determine the lower limits in terms of an iterated logarithm law.

Jean Jacod

We determine the asymptotic behavior of the realized power variations, or more generally of sums of a given test function evaluated at the successive increments of a Lévy process. One can completely elucidate the first order behavior (convergence in probability, possibly after normalization). As for the associated CLT, one can show some versions of it, but o

Igor V. Dolgachev, Shigeyuki Kondo

These are lecture notes based on a series of talks given by the authors at the CIMPA Summer School on Algebraic Geometry and Hypergeometric Functions held in Istanbul in Summer of 2005. They provide an introduction to a recent work on the complex ball uniformization of the moduli spaces of Del Pezzo surfaces, K3 surfaces and algebraic curves of lower genus.

Xuhua He, George Lusztig

Let $G$ be a semisimple adjoint group over $\bold C$ and $\bar{G}$ be the De Concini-Procesi completion of $G$. In this paper, we define a Lagrangian subvariety $Λ$ of the cotangent bundle of $\bar{G}$ such that the singular support of any character sheaf on $\bar{G}$ is contained in $Λ$.

Endre Csáki, Antónia Földes, Pál Révész

Considering a simple symmetric random walk in dimension $d\geq 3$, we study the almost sure joint asymptotic behavior of two objects: first the local times of a pair of neighboring points, then the local time of a point and the occupation time of the surface of the unit ball around it.

Walter Bergweiler

A heuristic principle attributed to A. Bloch says that a family of holomorphic functions is likely to be normal if there is no nonconstant entire functions with this property. We discuss this principle and survey recent results that have been obtained in connection with it. We pay special attention to properties related to exceptional values of derivatives a

Sebastien Jansou

Given an affine scheme X with an action of a reductive group G and a G-linearized coherent sheaf M, we construct the ``invariant Quot scheme&#39;&#39; that parametrizes the quotients of M whose space of global sections is a direct sum of simple G-modules with fixed finite multiplicities. Then we determine the invariant Quot scheme in a simple situation, wher

William Y. C. Chen, Nelson Y. Li, Louis W. Shapiro

We introduce the notion of doubly rooted plane trees and give a decomposition of these trees, called the butterfly decomposition which turns out to have many applications. From the butterfly decomposition we obtain a one-to-one correspondence between doubly rooted plane trees and free Dyck paths, which implies a simple derivation of a relation between the Ca

Bas Lemmens, Beata Randrianantoanina, Onno van Gaans

We consider 1-complemented subspaces (ranges of contractive projections) of vector-valued spaces $\ell_p(X)$, where $X$ is a Banach space with a 1-unconditional basis and $p \in (1,2)\cup (2,\infty)$. If the norm of $X$ is twice continuously differentiable and satisfies certain conditions connecting the norm and the notion of disjointness with respect to the

Frédéric Campana, Jungkai A. Chen, Thomas Peternell

Let $X$ be a projective manifold of dimension $n$ and $L$ a strictly nef line bundle on $X$. Then $K_X+tL$ is ample if $t > n+1$ in the following cases. 1.) $\text{dim} X = 3$ unless (possibly) $X$ is a Calabi-Yau with $c_2 \cdot L=0$; 2.) $κ(X) \ge n-2$; 3.) $\text{dim} α(X) \ge n-2$, with $α: X \to A$ the Albanese map.

Anders Kock

For a fixed object X in a monoidal category, an X-commutation structure on an object A is just a map from XA to AX. We study aspects of such structure in case A has a dual.

Hartmut Pecher

The Cauchy problem for a coupled Schroedinger and Benjamin - Ono system is shown to be globally well-posed for a class of data without finite energy. The proof uses the I-method introduced by Colliander, Keel, Staffilani, Takaoka, and Tao.

Jaehyun Hong, Alan Huckleberry

Open orbits D of noncompact real forms G_0 acting on flag manifolds of their semisimple complexifications G are considered. The unique orbit C of a maximal compact subgroup K_0 of G_0 in D can be regarded as a point in the (full) cycle space of D. The group theoretical cycle space is defined to be the connected component containing C of the intersection of t

Gady Kozma

Let phi be a Dubins-Freedman random homeomorphism on [0,1] derived from the base measure uniform on the vertical line x=1/2, and let f be a periodic function satisfying that |f(x)-f(0)| = o(1/log log log 1/x). Then the Fourier expansion of f composed with phi converges at 0 with probability 1. In the condition on f, o cannot be replaced by O. Also we deduce

Michael T. Anderson

We prove certain weak or idealized existence results for minimizers of the natural quadratic curvature functionals on the space of metrics on 4-manifolds. Overall, we try to exhibit the relations with the picture in 3-dimensions provided by Thurston geometrization. The existence results apply in particular to the structure of the moduli spaces of such metric

Henry Crapo, William Schmitt

We introduce the matroid-minor coalgebra C, which has labeled matroids as distinguished basis, and coproduct given by splitting a matroid into a submatroid and complementary contraction all possible ways. We introduce two new bases for C; the first of these is is related to the distinguished basis by Mobius inversion over the rank-preserving weak order on ma

Stéphane Druel

A counter example to the main result has been communicated to the author by Matei Toma.

Giovanni Bassanelli, Marco Leoni

We construct a family of 1-convex threefolds, with exceptional curve C of type (0,-2), which are not embeddable in C^m \times CP_n. In order to show that they are not Kaehler we exhibit a real 3-dimensional chain A whose boundary is the complex curve C.

R. -O. Buchweitz, H. Flenner

We show that a formal power series ring $A[[X]]$ over a noetherian ring $A$ is not a projective module unless $A$ is artinian. However, if $(A,{\mathfrak m})$ is local, then $A[[X]]$ behaves like a projective module in the sense that $Ext^p_A(A[[X]], M)=0$ for all ${\mathfrak m}$-adically complete $A$-modules. The latter result is shown more generally for an