January 2006 arXiv papers

Renata Kallosh, Navin Sivanandam, Masoud Soroush

We study the attractor mechanism for extremal non-BPS black holes with an infinite throat near horizon geometry, developing, as we do so, a physical argument as to why such a mechanism does not exist in non-extremal cases. We present a detailed derivation of the non-supersymmetric attractor equation. This equation defines the stabilization of moduli near the

Ada Boralevi

We study the behavior of the Horrocks-Mumford bundle when restricted to a plane P^2 in P^4, looking for all possible minimal free resolutions for the restricted bundle. To each of the 6 resolutions (4 stable and 2 unstable) we find, we then associate a subvariety of the Grassmannian G(2,4) of planes in P^4. We thus obtain a filtration of the Grassmannian, wh

Keith Copsey, Gary T. Horowitz

We (numerically) construct new static, asymptotically AdS solutions where the conformal infinity is the product of time and S^2 x S^1. There always exist a family of solutions in which the S^1 is not contractible and, for small S^1, there are two additional families of solutions in which the S^1 smoothly pinches off. This shows that (when fermions are antipe

B. A. DiDonna, Alex J. Levine

The semiflexible F-actin network of the cytoskeleton is cross-linked by a variety of proteins including filamin, which contain Ig-domains that unfold under applied tension. We examine a simple semiflexible network model cross-linked by such unfolding linkers that captures the main mechanical features of F-actin networks cross-linked by filamin proteins and s

O. Naaman, J. Aumentado

We have measured, in real time, individual quasiparticle tunneling in a single Cooper pair transistor, using rf reflectometry on the supercurrent branch. We have extracted the even-to-odd and odd-to-even transition rates directly by analyzing the distributions of dwell times in the even and odd states of the transistor. We discuss both the measurement and an

Chethan Krishnan, Edoardo Di Napoli

If one tries to view de Sitter as a true (as opposed to a meta-stable) vacuum, there is a tension between the finiteness of its entropy and the infinite-dimensionality of its Hilbert space. We invetsigate the viability of one proposal to reconcile this tension using $q$-deformation. After defining a differential geometry on the quantum de Sitter space, we tr

Darren S. Reed, Fabio Governato, Thomas Quinn, Joachim Stadel

We construct mock galaxy catalogues to analyse clustering properties of a Lambda cold dark matter (LCDM) universe within a cosmological dark matter simulation of sufficient resolution to resolve structure down to the scale of dwarfs. We show that there is a strong age-clustering correlation for objects likely to host luminous galaxies, which includes the sat

Gang Chen, Ronen Rapaport, L. N. Pffeifer, K. West

We present compelling experimental evidence for a successful electrostatic trapping of two-dimensional dipolar excitons that results in stable formation of a well confined, high-density and spatially uniform dipolar exciton fluid. We show that, for at least half a microsecond, the exciton fluid sustains a density higher than the critical density for degenera

T. Leitner, L. Alvarez-Ruso, U. Mosel

We have developed a model to describe the interactions of neutrinos with nucleons and nuclei, focusing on the region of the quasielastic and Delta(1232) peaks. We describe neutrino nucleon collisions with a fully relativistic formalism which incorporates state-of-the-art parametrizations of the form factors for both the nucleon and the N-Delta transition. Th

Nalini Anantharaman, Steve Zelditch

We relate two types of phase space distributions associated to eigenfunctions $ϕ_{ir_j}$ of the Laplacian on a compact hyperbolic surface $X_Γ$: (1) Wigner distributions $\int_{S^*\X} a dW_{ir_j}=< Op(a)ϕ_{ir_j}, ϕ_{ir_j}>_{L^2(\X)}$, which arise in quantum chaos. They are invariant under the wave group. (2) Patterson-Sullivan distributions $PS_{ir_j}$, whic

P. Manimaran, Prasanta K. Panigrahi, Jitendra. C. Parikh

We apply a recently developed wavelet based approach to characterize the correlation and scaling properties of non-stationary financial time series. This approach is local in nature and it makes use of wavelets from the Daubechies family for detrending purpose. The built-in variable windows in wavelet transform makes this procedure well suited for the non-st

N. Kaiser

Based on a recent chiral approach to nuclear matter we calculate the in-medium interaction of nucleons at the Fermi surface $|\vec p_{1,2}|=k_f$. The isotropic part of this quasi-particle interaction is characterized by four density dependent (dimensionful) Fermi-liquid parameters: $f_0(k_f), f_0&#39;(k_f), g_0(k_f)$ and $g_0&#39;(k_f)$. In the approximation

O. A. Tretiakov, K. A. Matveev

Current switching in a double-barrier resonant tunneling structure is studied in the regime where the current-voltage characteristic exhibits intrinsic bistability, so that in a certain range of bias two different steady states of current are possible. Near the upper boundary V_{th} of the bistable region the upper current state is metastable, and because of

Ezequiel N. Pozzo, Daniel Dominguez

We show that the three-junction SQUID device designed for the Josephson flux qubit can be used to study the dynamics of quantum chaos when operated at high energies. We determine the parameter region where the system is classically chaotic. We calculate numerically the fidelity or Loschmidt echo (LE) in the quantum dynamics under perturbations in the magneti

Brian C. Thomas, Adrian L. Melott

We describe results of modeling the effects on Earth-like planets of long-duration gamma-ray bursts (GRBs) within a few kiloparsecs. A primary effect is generation of nitrogen oxide compounds which deplete ozone. Ozone depletion leads to an increase in solar UVB radiation at the surface, enhancing DNA damage, particularly in marine microorganisms such as phy

Jaspal Singh Aujla Jean-Christophe Bourin

Eigenvalues inequalities involving (log) convex/concav functions and Hermitian matrices, positive unital maps are considered. Simple proofs of Bhatia-Kittaneh inequality and Naimark dilation theorem are given.

Agung Budiyono

We discuss two-dimensional Madelung fluid dynamics whose irrotational case reduces into the Schrödinger equation for a free single particle. We show that the self-trapped spinning-stationary Madelung fluid reported in the previous paper can be analogically identified as an equilibrium thermodynamics system. This is done by making correspondence between Shann

Anca Constantin, Michael S. Vogeley

We present the first multi-parameter analysis of the narrow line AGN clustering properties. Estimates of the two-point correlation function (CF) based on SDSS DR2 data reveal that Seyferts are clearly less clustered than normal galaxies, while the clustering amplitude (r_0) of LINERs is consistent with that of the parent galaxy population. The similarities i

E. Kou, T. N. Pham

We investigate the branching ratios and CP asymmetries of the B -> pi pi processes measured in B factory experiments. Fits to the experimental data of this process indicate a large ratio of color-suppressed (C) to color-allowed (T) tree contributions. We investigate whether the large C/T can be explained within the QCD based model computation with i) a large

A. S. Alexandrov, A. M. Bratkovsky, V. V. Kabanov

Pairing of oxygen holes into heavy bipolarons in the paramagnetic phase and their magnetic pair-breaking in the ferromagnetic phase [the so-called current-carrier density collapse (CCDC)] has accounted for the first-order ferromagnetic phase transition, colossal magnetoresistance (CMR), isotope effect, and pseudogap in doped manganites. Here we propose an ex

Marco Spaans, Joseph Silk

The polytropic equation of state of an atomic hydrogen gas is examined for primordial halos with baryonic masses of M_h~10^7-10^9 Mo. For roughly isothermal collapse around 10^4 K, we find that line trapping of Lyman alpha (HI and HeII) photons causes the polytropic exponent to stiffen to values significantly above unity. Under the assumptions of zero H2 abu

Cristian Giardina&#39;, Shannon Starr

We compute the pressure of the random energy model (REM) and generalized random energy model(GREM) by establishing variational upper and lower bounds. For the upper bound, we generalize Guerra&#39;s ``broken replica symmetry bounds&#34;,and identify the random probability cascade as the appropriate random overlap structure for the model. For the REM the lowe

Carlo Ewerz

Gribov's scenario of confinement caused by supercritical charges is described and the present status of Gribov's equation for the Green function of light quarks is discussed.

O-Kab Kwon, Chong Oh Lee

We study an inhomogeneous decay of an unstable D-brane in the context of Dirac-Born-Infeld~(DBI)-type effective action. We consider tachyon and electromagnetic fields with dependence of time and one spatial coordinate, and an exact solution is found under an exponentially decreasing tachyon potential, $e^{-|T|/\sqrt{2}}$, which is valid for the description o

C. Amoruso, A. K. Hartmann, M. B. Hastings, M. A. Moore

We present numerical evidence that the techniques of conformal field theory might be applicable to two-dimensional Ising spin glasses with Gaussian bond distributions. It is shown that certain domain wall distributions in one geometry can be related to that in a second geometry by a conformal transformation. We also present direct evidence that the domain wa

Harald Luschgy, Gilles Pagès

We investigate the connections between the mean pathwise regularity of stochastic processes and their L^r(P)-functional quantization rates as random variables taking values in some L^p([0,T],dt)-spaces (0 < p <= r). Our main tool is the Haar basis. We then emphasize that the derived functional quantization rate may be optimal (e.g., for Brownian motion or sy

S. F. King, S. Moretti, R. Nevzorov

We discuss the spectrum of Higgs bosons in the framework of the exceptional supersymmetric standard model. The presence of a $Z&#39;$ and exotic particles predicted by the exceptional SUSY model allows the lightest Higgs particle to be significantly heavier than in the MSSM and NMSSM. When the mass of the lightest Higgs boson is larger than $135-140 {GeV}$ t

T. M. Aliev, M. Savci

We analyze the semileptonic (B_c -> B_u* l+ l-) decay in the frame work of the Standard Model. We calculate the (B_c) to (B_u*) transition form factors in QCD sum rules. Analytical expressions for the spectral densities and gluon condensates are presented. The branching ratio of the (B_c -> B_u* l+ l-) decay is calculated, and it is obtained that this decay

Mustafa Salti

This paper has been removed by arXiv administrators because it plagiarizes gr-qc/0303034 and gr-qc/0212018.

F. A. Correa, J. Morales

The chiral phase transition at a certain critical temperature is a restoration mechanism of the chiral symmetry, broken by the nonzero mass of quarks and mesons. The transition can be studied through several models, among which are the sigma models. An analysis is made on the linear and nonlinear sigma models with different approximations, and we show that t

M. Faure, A. I. Buzdin, A. A. Golubov, M. Yu. Kupriyanov

We investigate Superconductor/Ferromagnet (S/F) hybrid structures in the dirty limit, described by the Usadel equations. More precisely, the oscillations of the critical temperature and critical current with the thickness of the ferromagnetic layers are studied. We show that spin-flip and spin-orbit scattering lead to the decrease of the decay length and the

M. Pretti

We consider a lattice polymer model (random walk), in which the walk is allowed to visit lattice bonds at most twice. Such a model might have some relevance to describe statistical properties of RNA molecules. In order to mimic base pairing, we assign an attractive energy term to each doubly-visited bond, and a further contribution to each pair of consecutiv

Jeremy Avigad, Harvey Friedman

<p>We address the general problem of determining the validity of boolean combinations of equalities and inequalities between real-valued expressions. In particular, we consider methods of establishing such assertions using only restricted forms of distributivity. At the same time, we explore ways in which &#34;local&#34; decision or heuristic procedures for

Indranil Biswas, A. J. Parameswaran

Let $X$ be a geometrically irreducible smooth projective curve defined over a field $k$. Assume that $X$ has a $k$-rational point; fix a $k$-rational point $x\in X$. From these data we construct an affine group scheme ${\mathcal G}_X$ defined over the field $k$ as well as a principal ${\mathcal G}_X$-bundle $E_{{\mathcal G}_X}$ over the curve $X$. The group

P. R. Rice, J. Gea-Banacloche, M. L. Terraciano, D. L. Freimund

We investigate steady state entanglement in an open quantum system, specifically a single atom in a driven optical cavity with cavity loss and spontaneous emission. The system reaches a steady pure state when driven very weakly. Under these conditions, there is an optimal value for atom-field coupling to maximize entanglement, as larger coupling favors a los

Paolo Sibani, G. F. Rodriguez, G. G. Kenning

A novel method for analyzing the intermittent behavior of linear response data in aging systems is presented and applied to spin-glass thermoremanent magnetization (TRM) (Rodriguez et al. Phys. Rev. Lett. 91, 037203, 2003). The probability density function (PDF) of magnetic fluctuations is shown to have an asymmetric exponential tail, demonstrating that the

L. A. Ferreira

We construct an infinite number of exact time dependent soliton solutions, carrying non-trivial Hopf topological charges, in a 3+1 dimensional Lorentz invariant theory with target space S^2. The construction is based on an ansatz which explores the invariance of the model under the conformal group SO(4,2) and the infinite dimensional group of area preserving

Miloslav Dusek, Norbert Lutkenhaus, Martin Hendrych

Elementary review article on quantum cryptography.

Nathan Seiberg

We summarize the arguments that space and time are likely to be emergent notions; i.e. they are not present in the fundamental formulation of the theory, but appear as approximate macroscopic concepts. Along the way we briefly review certain topics. These include ambiguities in the geometry and the topology of space which arise from dualities, questions asso

Jason Lotay

The principal theory of this paper comprises a technique for constructing associative, coassociative and Cayley submanifolds of Euclidean space with symmetries, using first-order ordinary differential equations. Explicit examples of U(1)-invariant associative cones in R^7 and SU(2)-invariant Cayley 4-folds in R^8 are then produced using this method. Further

Ryo Yamazaki, Kazunori Kohri, Aya Bamba, Tatsuo Yoshida

We study the emission from an old supernova remnant (SNR) with an age of around 10^5 yrs and that from a giant molecular cloud (GMC) encountered by the SNR. When the SNR age is around 10^5 yrs, proton acceleration is efficient enough to emit TeV gamma-rays both at the shock of the SNR and that in the GMC. The maximum energy of primarily accelerated electrons

Takashi Maeda, Toshio Nakatsu

We study a statistical model of random plane partitions. The statistical model has interpretations as five-dimensional $\mathcal{N}=1$ supersymmetric SU(N) Yang-Mills on $\mathbb{R}^4\times S^1$ and as Kähler gravity on local SU(N) geometry. At the thermodynamic limit a typical plane partition called the limit shape dominates in the statistical model. The li

Adel Bilal, Steffen Metzger

We consider N=1 supersymmetric U(N) gauge theories with Z_k symmetric tree-level superpotentials W for an adjoint chiral multiplet. We show that (for integer 2N/k) this Z_k symmetry survives in the quantum effective theory as a corresponding symmetry of the effective superpotential W_eff(S_i) under permutations of the S_i. For W(x)=^W(h(x)) with h(x)=x^k, th

Josef L. P. Karthauser, P. M. Saffin

The evolution of multiple scalar fields in cosmology has been much studied, particularly when the potential is formed from a series of exponentials. For a certain subclass of such systems it is possible to get `assisted` behaviour, where the presence of multiple terms in the potential effectively makes it shallower than the individual terms indicate. It is a

Pablo Suárez-Serrato

We show vanishing results about the infimum of the topological entropy of the geodesic flow of homogeneous smooth four manifolds. We prove that any closed oriented geometric four manifold has zero minimal entropy if and only if it has zero simplicial volume. We also show that if a four manifold M admits a geometric decomposition, in the sense of Thurston, an

Igor Loutsenko, Oksana Yermolayeva

Dynamics of planar domains with moving boundaries driven by the gradient of a scalar field that satisfies an elliptic PDE is studied. We consider the question: For which kind of PDEs the domains are algebraic, provided the field has singularities at a fixed point inside the domain? The construction reveals a direct connection with the theory of the Calogero-

Teodor Banica, Julien Bichon

We study quantum automorphism groups of vertex-transitive graphs having less than 11 vertices. With one possible exception, these can be obtained from cyclic groups ${\mathbb Z}_n$, symmetric groups $S_n$ and quantum symmetric groups $\mathcal Q_n$, by using various product operations. The exceptional case is that of the Petersen graph, and we present some q

J. Kluson

This paper is devoted to the study of the dynamics of the Dp-branes, F-strings and M-branes in the background of the system of two stacks of fivebranes in type IIA, IIB and M theory that intersect on the line.

Jean-Guillaume Dumas, Pascal Giorgi, Clément Pernet

In the past two decades, some major efforts have been made to reduce exact (e.g. integer, rational, polynomial) linear algebra problems to matrix multiplication in order to provide algorithms with optimal asymptotic complexity. To provide efficient implementations of such algorithms one need to be careful with the underlying arithmetic. It is well known that

S. E. Krüger, R. Darradi, J. Richter, D. J. J Farnell

We present a method for the direct calculation of the spin stiffness by means of the coupled cluster method. For the spin-half Heisenberg antiferromagnet on the square, the triangular and the cubic lattices we calculate the stiffness in high orders of approximation. For the square and the cubic lattices our results are in very good agreement with the best re

R. Rastegar, M. R. Meybodi

The Estimation of Distribution Algorithm is a new class of population based search methods in that a probabilistic model of individuals is estimated based on the high quality individuals and used to generate the new individuals. In this paper we compute 1) some upper bounds on the number of iterations required for global convergence of EDA 2) the exact numbe

Jared Kaplan

We analyze a simple Split Supersymmetry scenario where fermion masses come from anomaly mediation, yielding m_s ~ 1000 TeV, m_{3/2} ~ 100 TeV, and m_f ~ 1 TeV. We consider non-thermal dark matter production in the presence of moduli, and we find that the decay chains of moduli to LSPs and moduli to gravitinos to LSPs generate dark matter more efficiently tha

Ralph L. Cohen, Ib Madsen

In this paper we study the topology of the space of Riemann surfaces in a simply connected space X, S_{g,n} (X, γ). This is the space consisting of triples, (F_{g,n}, ϕ, f), where F_{g,n} is a Riemann surface of genus g and n-boundary components, ϕis a parameterization of the boundary, and f : F_{g,n} \to X is a continuous map that satisfies a boundary condi

N. Ota, N. Inada, M. Oguri, K. Mitsuda

We present results from Chandra observations of SDSS J1004+4112, a strongly lensed quasar system with a maximum image separation of 15&#34;. All four bright images of the quasar, as well as resolved X-ray emission originating from the lensing cluster, are clearly detected. The emission from the lensing cluster extends out to approximately 1.5 arcmin. We meas

Joel B. Predd, Sanjeev R. Kulkarni, Daniel N. Osherson, H. Vincent Poor

In this paper, computational aspects of the panel aggregation problem are addressed. Motivated primarily by applications of risk assessment, an algorithm is developed for aggregating large corpora of internally incoherent probability assessments. The algorithm is characterized by a provable performance guarantee, and is demonstrated to be orders of magnitude

B. Doug Park, Mainak Poddar, Stefano Vidussi

We construct an infinite family of homologous, non-isotopic, symplectic surfaces of any genus greater than one in a certain class of closed, simply connected, symplectic four-manifolds. Our construction is the first example of this phenomenon for surfaces of genus greater than one.

Oswin Aichholzer, David Orden, Francisco Santos, Bettina Speckmann

We pose a monotonicity conjecture on the number of pseudo-triangulations of any planar point set, and check it on two prominent families of point sets, namely the so-called double circle and double chain. The latter has asymptotically $12^n n^{\Theta(1)}$ pointed pseudo-triangulations, which lies significantly above the maximum number of triangulations in a

Siamak Khademi, Sadollah Nasiri

In this paper, operator gauge transformation, first introduced by Kobe, is applied to Maxwell&#39;s equations and continuity equation in QED. The gauge invariance is satisfied after quantization of electromagnetic fields. Inherent nonlinearity in Maxwell&#39;s equations is obtained as a direct result due to the nonlinearity of the operator gauge transformati

A Ruschhaupt, J G Muga, M G Raizen

Different laser devices working as ``atom diodes&#39;&#39; or ``one-way barriers&#39;&#39; for ultra-cold atoms have been proposed recently. They transmit ground state level atoms coming from one side, say from the left, but reflect them when they come from the other side. We combine a previous model, consisting of the stimulated Raman adiabatic passage (STI

Tobias Gleim

Seeking for a relativistic generalisation of the non-relativistic Schroedinger equation, one very soon arrives at equations with a square-root operator by having applied the quantum mechanical correspondence principle to the formula of relativistic energy. The problems of these equations are at least two fold: when coupled to an electromagnetic field, their

A. A. Methot, V. Scarani

Ever since the work of Bell, it has been known that entangled quantum states can rise non-local correlations. However, for almost forty years, it has been assumed that the most non-local states would be the maximally entangled ones. Surprisingly it is not the case: non-maximally entangled states are generally more non-local than maximally entangled states fo

E. Gozzi, D. Mauro

Classical mechanics, in the operatorial formulation of Koopman and von Neumann, can be written also in a functional form. In this form two Grassmann partners of time make their natural appearance extending in this manner time to a three dimensional supermanifold. Quantization is then achieved by a process of dimensional reduction of this supermanifold. We pr

Chi-Yee Cheung

The impossibility proof of unconditionally secure quantum bit commitment is crucially dependent on the assertion that Bob is not allowed to generate probability distributions unknown to Alice. This assertion is actually not meaningful, because Bob can always cheat without being detected. In this paper we prove that, for any concealing protocol involving secr

Fatemeh Ghasemi, J. Peinke, M. Reza Rahimi Tabar, Muhammad Sahimi

Statistical properties of interbeat intervals cascade are evaluated by considering the joint probability distribution $P(Δx_2,τ_2;Δx_1,τ_1)$ for two interbeat increments $Δx_1$ and $Δx_2$ of different time scales $τ_1$ and $τ_2$. We present evidence that the conditional probability distribution $P(Δx_2,τ_2|Δx_1,τ_1)$ may obey a Chapman-Kolmogorov equation. T

Hiro-Sato Niwa

I address the question of the fluctuations in fishery landings. Using the fishery statistics time-series collected by the Food and Agriculture Organization of the United Nations since the early 1950s, I here analyze fishing activities and find two scaling features of capture fisheries production: (i) the standard deviation of growth rate of the domestically

Denis Boyer, Gabriel Ramos-Fernández, Octavio Miramontes, José L. Mateos

Scale-free foraging patterns are widespread among animals. These may be the outcome of an optimal searching strategy to find scarce randomly distributed resources, but a less explored alternative is that this behaviour may result from the interaction of foraging animals with a particular distribution of resources. We introduce a simple foraging model where i

Radek Erban, Jonathan Chapman, Kerry D. Fisher, Ioannis G. Kevrekidis

Many drug delivery systems suffer from undesirable interactions with the host immune system. It has been experimentally established that covalent attachment (irreversible adsorption) of suitable macromolecules to the surface of the drug carrier can reduce such undesirable interactions. A fundamental understanding of the adsorption process is still lacking. I

K. -I. Goh, Y. -H. Eom, H. Jeong, B. Kahng

With the advancement in the information age, people are using electronic media more frequently for communications, and social relationships are also increasingly resorting to online channels. While extensive studies on traditional social networks have been carried out, little has been done on online social network. Here we analyze the structure and evolution

Silvio M. Duarte Queiros, Luis G. Moyano, Jeferson de Souza, Constantino Tsallis

We present results about financial market observables, specifically returns and traded volumes. They are obtained within the current nonextensive statistical mechanical framework based on the entropy $S_{q}=k\frac{1-\sum\limits_{i=1}^{W} p_{i} ^{q}}{1-q} (q\in \Re)$ ($S_{1} \equiv S_{BG}=-k\sum\limits_{i=1}^{W}p_{i} \ln p_{i}$). More precisely, we present st

J. J. Blostein, J. Dawidowski, J. R. Granada

We analyze a recent work of Mayers and Abdul-Redah,[J.Phys.: Condens. Matter {\bf 16}, 4811 (2004)] in which the autors report the existence of anomalous neutron cross sections in several systems. In the present work we show that the Deep Inelastic Neutron Scattering (DINS) results presented by the authors are affected by an inaccurate formalism employed for

H. Schmitz, R. Grauer

We present a new Vlasov code for collisionless plasmas in the nonrelativistic regime. A Darwin approximation is used for suppressing electromagnetic vacuum modes. The spatial integration is based on an extension of the flux-conservative scheme, introduced by Filbet et al. [J. Comp. Phys. Vol. 172 (2001) 166]. Performance and accuracy is demonstrated by compa

A. A. Koronovskii, A. E. Hramov

Results are presented from numerical modeling of the effect of the inhomogeneity of the ion background on the complicated spatiotemporal dynamics of an electron beam with a virtual cathode in plane geometry. The possibility is demonstrated of increasing the generation frequency without changing the beam current. The spatiotemporal structures that form in the

N. Kaiser

We calculate the density-dependent spin-isospin asymmetry energy $J(k_f)$ of nuclear matter in the three-loop approximation of chiral perturbation theory. The interaction contributions to $J(k_f)$ originate from one-pion exchange, iterated one-pion exchange, and irreducible two-pion exchange with no, single, and double virtual $Δ$-isobar excitation. We find

N. Kaiser

Using SU(3) chiral perturbation theory we calculate the density-dependent complex mean field $U_Σ(k_f)+ i W_Σ(k_f)$ of a $Σ$-hyperon in isospin-symmetric nuclear matter. The leading long-range $ΣN $-interaction arises from one-kaon exchange and from two-pion exchange with a $Σ$- or a $Λ$-hyperon in the intermediate state. We find from the $ΣN\to ΛN$ conversi

N. Kaiser

We calculate in chiral perturbation theory the dominant next-to-leading order correction to the $πγ$-exchange NN-potential proportional to the large isovector magnetic moment $κ_v = 4.7$ of the nucleon. The corresponding spin-spin and tensor potentials $\widetilde V_{S,T}(r)$ in coordinate space have a very simple analytical form. At long distances $r \simeq

A. M. Moro, F. Perez-Bernal, J. M. Arias, J. Gomez-Camacho

The problem of Coulomb breakup in the scattering of a two-body loosely bound projectile by a heavy target is addressed. A basis of transformed harmonic oscillator (THO) wave functions is used to discretize the projectile continuum and to diagonalize the Hamiltonian of the two-body system. Results for the reaction $^{8}$B+$^{58}$Ni at subcoulomb energies are

V. M. Kolomietz, S. V. Lukyanov, S. Shlomo

The validity of small damping approximation (SDA) for the quasi-classical description of the averaged properties of nuclei at high temperatures is studied within the framework of collisional kinetic theory. The isoscalar collective quadrupole vibrations in hot nuclei are considered. We show that the extension of the SDA, by accounting for the damping of the

Calvin W. Johnson, Hai Ah Nam

Recent investigations have looked at the many-body spectra of random two-body interactions. In fermion systems, such as the interacting shell model, one finds pairing-like spectra, while in boson systems, such as IBM-1, one finds rotational and vibrational spectra. We discuss the search for random ensembles of fermion interactions that yield rotational and v

The STAR, STAR-RICH Collaborations

Data for Au+Au collisions at sqrt{s_{NN}}=200 GeV are analyzed to determine the ratios of identified hadrons ($π$, $K$, $p$, $Λ$) as functions of collision centrality and transverse momentum ($p_T$). We find that ratios of anti-baryon to baryon yields are independent of $p_T$ up to 5 GeV/c, a result inconsistent with results of theoretical pQCD calculations

Faruk Gungor

We discuss Lie algebras of the Lie symmetry groups of two generically non-integrable equations in one temporal and two space dimensions arising in different contexts. The first is a generalization of the KP equation and contains 9 arbitrary functions of one and two arguments. The second one is a system of PDEs that depend on some physical parameters. We requ

A. A. Koronovskii, A. E. Hramov, I. A. Khromova

We consider the time required for complete synchronization of two identical one-way coupled vander Pol-Duffing oscillators occurring in the regime of dynamic chaos. The influence of the initial phase differ-ence between oscillators on the duration of the process of complete synchronization has been studied. At a fixedphase of chaotic oscillations of the self

A. A. Koronovskii, A. E. Hramov, I. A. Khromova

The mechanism of synchronization of oscillations in two identical coupled flow systems has beenstudied. The time (past the coupling onset) during which a synchronous oscillation regime is establisheddepends on the oscillation phase difference between the subsystems. Variation of the coupling parameter leadsto a change in the character of dependence of the sy

A. A. Koronovskii, A. V. Starodubov, A. E. Hramov

We describe a method for determining the transient process duration in a standard two-dimensionaldynamic system with discrete time (Henon map), occurring in the regime of chaotic oscillations

E. N. Egorov, A. A. Koronovskii, A. E. Hramov

Transient processes in a third-order radiophysical flow system are studied and a map of the transient process duration versus initial conditions is constructed and analyzed. The results are compared to the arrangement of submanifolds of the stable and unstable cycles in the Poincare section of the system studied.

J. A. Calzada, J. Negro, M. A. del Olmo

We study the dynamical symmetries of a class of two-dimensional superintegrable systems on a 2-sphere, obtained by a procedure based on the Marsden-Weinstein reduction, by considering its shape-invariant intertwining operators. These are obtained by generalizing the techniques of factorization of one-dimensional systems. We firstly obtain a pair of noncommut

A. A. Koronovskii, A. E. Hramov

Dependence of the transient process duration on the initial conditions is considered in one- and two-dimensional systems with discrete time, representing a logistic map and the Eno map, respectively.

G. B. Astaf&#39;ev, A. A. Koronovskii, A. E. Hramov

The transient chaos regime in a two-dimensional system with discrete time (Eno map) is considered. It is demonstrated that a time series corresponding to this regime differs from a chaotic series constructed for close values of the control parameters by the presence of &#34;nonregular&#34; regions, the number of which increases with the critical parameter. A

P. J. Forrester

The distributions of the smallest and largest eigenvalues for the matrix product $Z^\dagger Z$, where $Z$ is an $n \times m$ complex Gaussian matrix with correlations both along rows and down columns, are expressed as $m \times m$ determinants. In the case of correlation along rows, these expressions are computationally more efficient than those involving su

J. A. Calzada, J. Negro, M. A. del Olmo

A class of two-dimensional superintegrable systems on a constant curvature surface is considered as the natural generalization of some well known one-dimensional factorized systems. By using standard methods to find the shape-invariant intertwining operators we arrive at a $so(6)$ dynamical algebra and its Hamiltonian hierarchies. We pay attention to those a

Christian Remling

I point out finite propagation speed phenomena for discrete and continuous Schrödinger operators and discuss kernel estimates from this point of view.

Denis I. Borisov

In the paper we study the discrete spectrum of a pair of quantum two-dimensional waveguides having common boundary in which a window of finite length is cut out. We study the phenomenon of new eigenvalues emerging from the threshold of the essential spectrum when the length of window passes through critical values. We construct the asymptotics expansions for

Daniel H. T. Franco, Luiz H. Renoldi

In this paper we study the Fourier-Laplace transform of tempered ultrahyperfunctions introduced by Sebastião e Silva and Hasumi. We establish a generalization of Paley-Wiener-Schwartz theorem for this setting. This theorem is interesting in connection with the microlocal analysis. For this reason, the paper also contains a description of the singularity stru

Richard F. Bass, Xia Chen, Jay Rosen

Given a symmetric random walk in $Z^2$ with finite second moments, let $R_n$ be the range of the random walk up to time $n$. We study moderate deviations for $R_n -E R_n$ and $E R_n -R_n$. We also derive the corresponding laws of the iterated logarithm.

G. Androulakis, K. Beanland

A Hereditarily Indecomposable asymptotic $\ell_2$ Banach space is constructed. The existence of such a space answers a question of B. Maurey and verifies a conjecture of W.T. Gowers.

H. -J. Baues, M. Jibladze, T. Pirashvili

There is a long-standing problem of algebra to extend the symmetric monoidal structure of abelian groups, given by the tensor product, to a non abelian setting. In this paper we show that such an extension is possible. Morover our non abelian tensor product remains even right exact and balanced. We describe the new non-abelian tensor product in the context o

P. Salminen, O. Wallin

In this paper we study perpetual integral functionals of diffusions. Our interest is focused on cases where such functionals can be expressed as first hitting times for some other diffusions. In particular, we generalize the result which connects one-sided functionals of Brownian motion with drift with first hitting times of reflecting diffusions. Interpreta

Jean-Marc Rasoamanana

In this article, we investigate the resurgent properties of the WKB solutions for a singularly perturbated second order ordinary differential equation. In particular, we extend and propose a new proof of a theorem due to Aoki (et al) near a simple turning point, in the framework of the exact WKB analysis. Our scheme of proof is based on a Laplace-integral re

Victor Palamodov

Global constructions of quantization deformation and obstructions are discussed for an arbitrary complex analytic space in terms of adapted (analytic) Hochschild cohomology. For K3-surfaces an explicit global construction of a Poisson bracket is given. It is shown that the analytic Hochschild (co)homology on a complex space has structure of coherent analytic

Priska Jahnke, Ivo Radloff

We study smoothings of Fano threefolds. We prove that the Picard number remains constant in the case of terminal Gorenstein singularities.

Stefan Felsner

We consider rectangle graphs whose edges are defined by pairs of points in diagonally opposite corners of empty axis-aligned rectangles. The maximum number of edges of such a graph on $n$ points is shown to be 1/4 n^2 +n -2. This number also has other interpretations: * It is the maximum number of edges of a graph of dimension $\bbetween{3}{4}$, i.e., of a g