December 2005 arXiv papers — page 29

Dmitry Jakobson, Nikolai Nadirashvili, Iosif Polterovich

The first eigenvalue of the Laplacian on a surface can be viewed as a functional on the space of Riemannian metrics of a given area. Critical points of this functional are called extremal metrics. The only known extremal metrics are a round sphere, a standard projective plane, a Clifford torus and an equilateral torus. We construct an extremal metric on a Kl

F. R. Joaquim

I review some aspects related with the connections between neutrino physics and the thermal leptogenesis mechanism for the generation of the cosmological baryon asymmetry of the Universe. A special attention is devoted to the problem of establishing a bridge between leptonic CP violation at low and high energies.

Klaus P. Jungmann

Low energy antiprotons offer excellent opportunities to study properties of fundamental forces and symmetries in nature. Experiments with them can contribute substantially to deepen our fundamental knowledge in atomic, nuclear and particle physics. Searches for new interactions can be carried out by studying discrete symmetries. Known interactions can be tes

Joshua Stinehour, Stanisław Radziszowski, Kung-Kuen Tse

We determine the value of the Ramsey number $R(W_5,K_5)$ to be 27, where $W_5 = K_1 + C_4$ is the 4-spoked wheel of order 5. This solves one of the four remaining open cases in the tables given in 1989 by George R. T. Hendry, which included the Ramsey numbers $R(G,H)$ for all pairs of graphs $G$ and $H$ having five vertices, except seven entries. In addition

Dirk Wagner, John Noga

We conjecture the expected value of random walks with anti-correlated steps to be exactly 1. We support this conjecture with 2 plausibility arguments and experimental data. The experimental analysis includes the computation of the expected values of random walks for steps up to 22. The result shows the expected value asymptotically converging to 1.

Xiaoyang Gu, Jack H. Lutz, Elvira Mayordomo

The ``analyst's traveling salesman theorem'' of geometric measure theory characterizes those subsets of Euclidean space that are contained in curves of finite length. This result, proven for the plane by Jones (1990) and extended to higher-dimensional Euclidean spaces by Okikiolu (1991), says that a bounded set $K$ is contained in some curve of f

Jianqin Zhou

Based on the definition of generalized partially bent functions, using the theory of linear transformation, the relationship among generalized partially bent functions over ring Z N, generalized bent functions over ring Z N and affine functions is discussed. When N is a prime number, it is proved that a generalized partially bent function can be decomposed a

Jianqin Zhou

A fast algorithm is presented for determining the linear complexity and the minimal polynomial of periodic sequences over GF(q) with period q n p m, where p is a prime, q is a prime and a primitive root modulo p2. The algorithm presented here generalizes both the algorithm in [4] where the period of a sequence over GF(q) is p m and the algorithm in [5] where

Jianqin Zhou, Xirong Xu

The union cost is used, so that an efficient algorithm for computing the k-error linear complexity of a sequence with period 2pn over GF(q) is presented, where p and q are odd primes, and q is a primitive root of modulo p2.

C. L. Henley, M. de Boissieu, W. Steurer

This paper summarises a two-hour discussion at the Ninth International Conference on Quasicrystals, including nearly 20 written comments sent afterwards, concerning (i) the meaning [if any] of clusters in quasicrystals; (ii) phason elasticity, and (iii) thermodynamic stabilisation of quasicrystals.

C. L. Henley

Personal comments are made about the title subjects, including: the relation of Friedel oscillations to Hume-Rothery stabilisation; how calculations may resolve the random-tiling versus ideal pictures of quasicrystals; and the role of entropies apart from tile-configurational.

Nan Gu, C. L. Henley, M. Mihalkovic

We apply systematic methods previously used by Mihalkovic et al. to predict the structure of the `basic' Co-rich modification of the decagonal Al70 Co20 Ni10 layered quasicrystal, based on known lattice constants and previously calculated pair potentials. The modelling is based on Penrose tile decoration and uses Monte Carlo annealing to discover the dom

Riccardo Guida, Paolo Ribeca

Within the framework of field-theoretical description of second-order phase transitions via the 3-dimensional O(N) vector model, accurate predictions for critical exponents can be obtained from (resummation of) the perturbative series of Renormalization-Group functions, which are in turn derived --following Parisi's approach-- from the expansions of appr

V. S. Gerdjikov, B. B. Baizakov, M. Salerno, N. A. Kostov

Perturbed version of the complex Toda chain (CTC) has been employed to describe adiabatic interactions within N-soliton train of the nonlinear Schrodinger equation (NLS). Perturbations induced by weak quadratic and periodic external potentials are studied by both analytical and numerical means. It is found that the perturbed CTC adequately models the N-solit

F. Karimi Pour Haddadan, S. Dietrich

We consider a nematic liquid crystal confined by two parallel flat substrates whose anchoring conditions vary periodically in one lateral direction. Within the Gaussian approximation, we study the effective forces between the patterned substrates induced by the thermal fluctuations of the nematic director. The shear force oscillates as function of the latera

Hiroki Saito, Yuki Kawaguchi, Masahito Ueda

We show that a spin-1 Bose-Einstein condensate with ferromagnetic interactions spontaneously generates a topological spin texture, in which the m = \pm 1 components of the magnetic sublevels form vortices with opposite circulations. This phenomenon originates from an interplay between ferromagnetic interactions and spin conservation.

Michael K. Rivera, W. Brent Daniel, Robert E. Ecke

Measurements of Lagrangian single-point and multiple-point statistics in a quasi-two-dimensional stratifed layer system are reported. The system consists of a layer of salt water over an immiscible layer of Fluorinert and is forced electromagnetically so that mean-squared vorticity is injected at a well-defined spatial scale. Simultaneous cascades develop in

Vitor Cardoso, Marco Cavaglia, Leonardo Gualtieri

We compute the absorption cross section and the total power carried by gravitons in the evaporation process of a higher-dimensional non-rotating black hole. These results are applied to a model of extra dimensions with standard model fields propagating on a brane. The emission of gravitons in the bulk is highly enhanced as the spacetime dimensionality increa

Danielle O'Donnol

We prove that every embedding of $K_{2n+1,2n+1}$ into $\R^3$ contains a non-split link of $n$-components. Further, given an embedding of $K_{2n+1,2n+1}$ in $\R^3$, every edge of $K_{2n+1,2n+1}$ is contained in a non-split $n$-component link in $K_{2n+1,2n+1}$.

Alessandra Agostini

The algebra of functions on kappa-Minkowski noncommutative spacetime is studied as algebra of operators on Hilbert spaces. The representations of this algebra are constructed and classified. This new approach leads to a natural construction of integration in kappa-Minkowski spacetime in terms of the usual trace of operators.

B. Alver

We present transverse momentum distributions of charged hadrons produced in Cu+Cu collisions at sqrt(s) = 62.4 and 200 GeV. The spectra are measured for transverse momenta of 0.25 < p_T < 5.0 GeV/c at sqrt(s) = 62.4 GeV and 0.25 < p_T < 7.0 GeV/c at sqrt(s) = 200 GeV, in a pseudo-rapidity range of 0.2 < eta < 1.4. The nuclear modification factor R_AA is calc

Laurent Freidel, Etera R. Livine

We show that the effective dynamics of matter fields coupled to 3d quantum gravity is described after integration over the gravitational degrees of freedom by a braided non-commutative quantum field theory symmetric under a kappa-deformation of the Poincare group.

Asaf Nachmias, Yuval Peres

We give a short proof that the largest component of the random graph $G(n, 1/n)$ is of size approximately $n^{2/3}$. The proof gives explicit bounds for the probability that the ratio is very large or very small.

Aristoklis D. Anastasiadis, George D. Magoulas

In this paper, inspired from our previous algorithm, which was based on the theory of Tsallis statistical mechanics, we develop a new evolving stochastic learning algorithm for neural networks. The new algorithm combines deterministic and stochastic search steps by employing a different adaptive stepsize for each network weight, and applies a form of noise t

G. Valencia, Yili Wang

We study a CP-violating triple product correlation that occurs in the decay of a neutral Higgs boson into t\bar{t} pairs when the Higgs boson does not have a definite CP nature. We consider the H -> t \bar{t} decay channel as well as the gluon fusion process gg -> H -> t \bar{t}. The asymmetry in Higgs decay, normalized to the H -> t \bar{t} width, can reach

Hongjie Dong, N. V. Krylov

Time-inhomogeneous controlled diffusion processes in both cylindrical and noncylindrical domains are considered. Bellman&#39;s principle and its applications to proving the continuity of value functions are investigated.

David A. Sahakyan, Tadashi Takayanagi

We study the scattering amplitudes in the N=2 minimal string or equivalently in the N=4 topological string on ALE spaces. We find an interesting connection between the tree level amplitudes of the N=2 minimal string and those of the (1,n) minimal bosonic string. In particular we show that the four and five-point functions of the N=2 string can be directly re

C. Grimaldi, E. Cappelluti, F. Marsiglio

We calculate the spin-Hall conductivity of a disordered two-dimensional Rashba electron gas within the self-consistent Born approximation and for arbitrary values of the electron density, parametrized by the ratio $E_F /E_0$, where $E_F$ is the Fermi level and $E_0$ is the spin-orbit energy. We confirm earlier results indicating that in the limit $E_F/E_0 \g

Robert G. Leigh, Djordje Minic, Alexandr Yelnikov

We analytically compute the spectrum of the spin zero glueballs in the planar limit of pure Yang-Mills theory in 2+1 dimensions. The new ingredient is provided by our computation of a new non-trivial form of the ground state wave-functional. The mass spectrum of the theory is determined by the zeroes of Bessel functions, and the agreement with large N lattic

Sergei Nayakshin

We consider the structure of self-gravitating marginally stable accretion disks in galactic centers in which a small fraction of the disk mass has been converted into proto-stars. We find that proto-stars accrete gaseous disk matter at prodigious rates. Mainly due to the stellar accretion luminosity, the disk heats up and geometrically thickens, shutting off

Charlie Conroy, Risa H. Wechsler, Andrey V. Kravtsov

We employ high-resolution dissipationless simulations of the concordance LCDM cosmology to model the observed luminosity dependence and evolution of galaxy clustering through most of the age of the universe, from z~5 to z~0. We use a simple, non-parametric model which monotonically relates galaxy luminosities to the maximum circular velocity of dark matter h

Yunfeng Jiang, Hsian-Hua Tseng

Hypertoric varieties are determined by hyperplane arrangements. In this paper, we use stacky hyperplane arrangements to define the notion of hypertoric Deligne-Mumford stacks. Their orbifold Chow rings are computed. As an application, some examples related to crepant resolutions are discussed.

A. R. Samana, T. Tarutina, F. Krmpotić, M. S. Hussein

We present an exploratory study of structure of 13C, 15C, 17C and 19C, showing that the simple one-quasiparticle projected BCS (PBCS) model is capable to account for several important properties of these nuclei. Next we discuss the importance of the Pauli Principle in the particle-core models of normal-parity states in 13C and 11Be. This is done by consideri

Ken Dykema, Hanne Schultz

We consider the Aluthge transform $|T|^{1/2}U|T|^{1/2}$ of a Hilbert space operator $T$, where $T=U|T|$ is the polar decomposition of $T$. We prove that the map that sends $T$ to its Aluthge transform is continuous with respect to the norm topology and with respect to the $*$--SOT topology on bounded sets. We consider the special case in a tracial von Neuman

Mats Boij, Fabrizio Zanello

This paper can be seen as a continuation of the works contained in the recent preprints [Za], of the second author, and [Mi], of Juan Migliore. Our results are: 1). There exist codimension three artinian level algebras of type two which do not enjoy the Weak Lefschetz Property (WLP). In fact, for $e\gg 0$, we will construct a codimension three, type two $h$-

Dean Lee

Using lattice effective field theory, we study the ground state binding energy of N distinct particles in two dimensions with equal mass interacting weakly via an attractive SU(N)-symmetric short range potential. We find that in the limit of zero range and large N, the ratio of binding energies B_{N}/B_{N-1} approaches the value 8.3(6).

Alwen Tiu

This paper studies properties of the logic BV, which is an extension of multiplicative linear logic (MLL) with a self-dual non-commutative operator. BV is presented in the calculus of structures, a proof theoretic formalism that supports deep inference, in which inference rules can be applied anywhere inside logical expressions. The use of deep inference res

F. Girelli, T. Konopka, J. Kowalski-Glikman, E. R. Livine

The phase space of a classical particle in DSR contains de Sitter space as the space of momenta. We start from the standard relativistic particle in five dimensions with an extra constraint and reduce it to four dimensional DSR by imposing appropriate gauge fixing. We analyze some physical properties of the resulting theories like the equations of motion, th

G. Glionna, A. H. Blin, B. Hiller, M. C. Nemes

We show that single and multislit experiments involving matter waves may be constructed to assess correlations between the position and momentum of a single free particle. These correlations give rise to position dependent phases which develop dynamically and may play an important role in the interference patterns. For large enough transverse coherence lengh

V. I. Shevchenko

The pattern of spontaneous chiral symmetry breaking (CSB) in confining background fields is analyzed. It is explicitly demonstrated how to get the inverse square root large proper time asymptotic of the operator product expansion which is needed for CSB.

Madalin Guta, Jonas Kahn

We consider n identically prepared qubits and study the asymptotic properties of the joint state ρ^{\otimes n}. We show that for all individual states ρsituated in a local neighborhood of size 1/\sqrt{n} of a fixed state ρ^0, the joint state converges to a displaced thermal equilibrium state of a quantum harmonic oscillator. The precise meaning of the conver

A. Di Giacomo, E. Meggiolaro, Yu. A. Simonov, A. I. Veselov

It is argued that strong dynamics in the quark-gluon plasma and bound states of quarks and gluons is mostly due to nonperturbative effects described by field correlators. The emphasis in the paper is made on two explicit calculations of these effects from the first principles: one analytic using gluelump Green&#39;s functions and another using independent la

Zeb W. Barber, Chad W. Hoyt, Chris W. Oates, Leo Hollberg

We report direct single-laser excitation of the strictly forbidden (6s^2)^1S_0 -(6s6p)^3P_0 clock transition in the even 174Yb isotope confined to a 1D optical lattice. A small (~1.2 mT) static magnetic field was used to induce a nonzero electric dipole transition probability between the clock states at 578.42 nm. Narrow resonance linewidths of 20 Hz (FHWM)

Hideo Kodama, Kunihito Uzawa

We derive four-dimensional effective theories for warped compactification of the ten-dimensional IIB supergravity and the eleven-dimensional Horava-Witten model. We show that these effective theories allow a much wider class of solutions than the original higher-dimensional theories. In particular, the effective theories have cosmological solutions in which

Ugo Boscain, Paolo Mason

In this paper we consider the minimum time population transfer problem for the $z$-component of the spin of a (spin 1/2) particle driven by a magnetic field, controlled along the x axis, with bounded amplitude. On the Bloch sphere (i.e. after a suitable Hopf projection), this problem can be attacked with techniques of optimal syntheses on 2-D manifolds. Let

S. Fratini, S. Ciuchi

The optical properties of polarons are studied in the framework of the Holstein model by applying the dynamical mean-field theory. This approach allows to enlighten important quantitative and qualitative deviations from the limiting treatments of small polaron theory, that should be considered when interpreting experimental data. In the antiadiabatic regime,

P. Zenczykowski

We give a joint description of weak radiative (WR) and nonleptonic (NL) hyperon decays (HD) in broken SU(3). The two groups of decays are linked via $SU(2)_W$ spin symmetry and vector meson dominance (VMD). We use experimental information on the parity-conserving (p.c.) NLHD amplitudes to fix the corresponding WRHD amplitudes. With the latter known, the data

Maximo Banados, Glenn Barnich, Geoffrey Compere, Andres Gomberoff

We construct Godel-type black hole and particle solutions to Einstein-Maxwell theory in 2+1 dimensions with a negative cosmological constant and a Chern-Simons term. On-shell, the electromagnetic stress-energy tensor effectively replaces the cosmological constant by minus the square of the topological mass and produces the stress-energy of a pressure-free pe

A. P. Bakulev, S. V. Mikhailov, N. G. Stefanis

We combine the constraints on the pion quark structure available from perturbative QCD, nonperturbative QCD (nonlocal QCD sum rules and light cone sum rules) with the analysis of current data on F_{πγγ^*}(Q^2), including recent high-precision lattice calculations of the second moment of the pion&#39;s distribution amplitude. We supplement these constraints w

Michael Sheinman, Shmuel Fishman, Italo Guarneri, Laura Rebuzzini

Experimentally observable Quantum Accelerator Modes are used as a test case for the study of some general aspects of quantum decay from classical stable islands immersed in a chaotic sea. The modes are shown to correspond to metastable states, analogous to the Wannier-Stark resonances. Different regimes of tunneling, marked by different quantitative dependen

Pieter Kok, W. J. Munro, Kae Nemoto, T. C. Ralph

Linear optics with photon counting is a prominent candidate for practical quantum computing. The protocol by Knill, Laflamme, and Milburn [Nature 409, 46 (2001)] explicitly demonstrates that efficient scalable quantum computing with single photons, linear optical elements, and projective measurements is possible. Subsequently, several improvements on this pr

E. Cappelluti

The anomalous features of the Raman spectroscopy measurement in MgB$_2$ represent a still unresolved puzzle. In particular highly debated are the origin of the huge $E_{2g}$ phonon linewidth, the nature of the low energy ($ω< ω_{E_{2g}}$) background and the evolution of the Raman spectra with Al doping. In this paper we compute the self-energy of the $E_{2g}

Thomas M. Liggett, Jeffrey E. Steif, Bálint Tóth

We show that a large collection of statistical mechanical systems with quadratically represented Hamiltonians on the complete graph can be extended to infinite exchangeable processes. This extends a known result for the ferromagnetic Curie--Weiss Ising model and includes as well all ferromagnetic Curie--Weiss Potts and Curie--Weiss Heisenberg models. By de F

Vincenzo Barone, Alessandro Cafarella, Claudio Coriano&#39;, Marco Guzzi

We present next-to-leading order predictions for double transverse-spin asymmetries in Drell--Yan dilepton production initiated by proton--antiproton scattering. The kinematic region of the proposed PAX experiment at GSI: $30\lesssim{s}\lesssim200\GeV^2$ and $2\lesssim{M}\lesssim7\GeV$ is examined. The Drell--Yan asymmetries turn out to be large, in the rang

Kenneth Pryor

This paper has been withdrawn by the author due to obsolete content.

R. Bellazzini, F. Angelini, L. Baldini, F. Bitti

We discuss a new class of Micro Pattern Gas Detectors, the Gas Pixel Detector (GPD), in which a complete integration between the gas amplification structure and the read-out electronics has been reached. An Application-Specific Integrated Circuit (ASIC) built in deep sub-micron technology has been developed to realize a monolithic device that is, at the same

Indranath Bhattacharyya

The decay of magneto-plasma into neutrino anti-neutrino pair has been studied in the framework of the electro-weak interaction theory. The decay rate is calculated and the expression for the energy-loss rate is obtained in the extreme relativistic case. The neutrino luminosity has also been computed for a neutron star. A comparative study between the decay o

Indranath Bhattacharyya

In this article the neutrino bremsstrahlung process is considered in presence of strong magnetic field, though the calculations for this process in absence of magnetic field are also carried out simultaneously. The electrons involved in this process are supposed to be highly degenerate and relativistic. The scattering cross sections and energy loss rates for

Galliano Valent, Hamed Ben Yahia

A countable class of integrable dynamical systems, with four dimensional phase space and conserved quantities in involution (H\_n,I\_n) are exhibited. For $n=1$ we recover Neumann sytem on T*S^2. All these systems are also integrable at the quantum level.

Tao Qin, Meisheng Zhao, Yongde Zhang

Quantum communications using continuous variables are quite mature experimental techniques and the relevant theories have been extensively investigated with various methods. In this paper, we study the continuous variable quantum channels from a different angle, i.e., by exploring master equations. And we finally give explicitly the capacity of the channel w

V. Uma

In this article we describe the $G\times G$-equivariant $K$-ring of $X$, where $X$ is a regular compactification of a connected complex reductive algebraic group $G$. Furthermore, in the case when $G$ is a semisimple group of adjoint type, and $X$ its wonderful compactification, we describe its ordinary $K$-ring $K(X)$. More precisely, we prove that $K(X)$ i

Y. Lu, K. S. Cheng, Y. F. Huang

Non-thermal TeV $γ$-ray emission within a multiparsec has been observed from the center region of our Galaxy. We argue that these $γ$-rays are the result of transient activity of the massive black hole Sgr A$^*$ that resides at the Galactic Center. Several thousand years ago, the black hole may have experienced an active phase by capturing a red giant star a

B. V. Petrenko, S. N. Sidki

Let $M_n(\mathbb{Z})$ the ring of $n$-by-$n$ matrices with integral entries, and $n \geq 2$. This paper studies the set $G_n(\mathbb{Z})$ of pairs $(A,B) \in M_n(\mathbb{Z})^2$ generating $M_n(\mathbb{Z})$ as a ring. We use several presentations of $M_{n}(\mathbb{Z})$ with generators $X=\sum_{i=1}^n E_{i+1,i}$ and $Y=E_{11}$ to obtain the following consequen

Zhen-Min Zhao, Qi-Ren Zhang, Chun-Yuan Gao, Yi-Zhong Zhuo

The potential energy surface of the H13 proton in base cytosine of the DNA molecules is calculated {\it ab initio} at the Gaussian98 MP2/6-311G(d,p) level. Two potential wells are found. One corresponds to the normal cytosine, while the other corresponds to its imino tautomer. The bindings of the proton in these wells are stable enough against the thermo-dis

Takehiko Yasuda

For each non-negative integer $n$, we define the $n$-th Nash blowup of an algebraic variety, and call them all higher Nash blowups. When $n=1$, it coincides with the classical Nash blowup. We study higher Nash blowups of curves in detail and prove that any curve in characteristic zero can be desingularized by its $n$-th Nash blowup with $n$ large enough.

Haibo Li, Maozhi Yang, Changzheng Yuan

In this letter, we discuss the possibility to look for the direct evidence of the existence of the ppbar and npbar bound states. Measurement of the single γray from the ppbar and npbar systems at rest can directly confirm whether the X(1860) and X(1835) are the resonances which are strongly coupled to ppbar. In addition to the neutral candidate, a charged re

Daria Ahrensmeier

Adiabatic quantum computation provides an alternative approach to quantum computation using a time-dependent Hamiltonian. The time evolution of entanglement during the adiabatic quantum search algorithm is studied, and its relevance as a resource is discussed.

M. Sasaki, S. Suzuki

We present a multimode theory of non-Gaussian operation induced by an imperfect on/off-type photon detector on a splitted beam from a wideband squeezed light. The events are defined for finite time duration $T$ in the time domain. The non-Gaussian output state is measured by the homodyne detector with finite bandwidh $B$. Under this time- and band-limitation

Mikio Fujiwara, Masahide Sasaki

We demonstrate multiphoton discrimination at telecom wavelength with the readout frequency of 40 Hz by charge integration photon detector (CIPD). The CIPD consists of an InGaAs pin photodiode and a GaAs junction field effect transistor as a pre-amplifier in a charge integration circuit, which is cooled to 4.2 K to reduce thermal noise. The quantum efficiency

Keiji Matsumoto

Consider a quantum system with $m$ subsystems with $n$ qubits each, and suppose the state of the system is living in the symmetric subspace. It is known that, in the limit of $m\to\infty$, entanglement between any two subsystems vanishes. In this paper we study asymptotic behavior of the entanglement as $m$ and $n$ grows. Our conjecture is that if $m$ is a p

M. Leonetti, P. Marcq, J. Nuebler, F. Homble

A salient feature of stationary patterns in tip-growing cells is the key role played by the symports and antiports, membrane proteins that translocate two ionic species at the same time. It is shown that these co-transporters destabilize generically the membrane voltage if the two translocated ions diffuse differently and carry a charge of opposite (same) si

Artem S. Novozhilov, Faina S. Berezovskaya, Eugene V. Koonin, Georgy P. Karev

A complete parametric analysis of dynamic regimes of a conceptual model of anti-tumor virus therapy is presented. The role and limitations of mass-action kinetics are discussed. A functional response, which is a function of the ratio of uninfected to infected tumor cells, is proposed to describe the spread of the virus infection in the tumor. One of the main

Daniel Oliveira Cajueiro, Reinaldo Soares De Camargo

In this paper, we introduce a framework to study local interactions due to the presence of herding behavior in a minority game. The idea behind this approach is to consider that some of the agents who play the game believe that some of their neighbors are more informed than themselves. Thus, in this way, these agents imitate their most informed neighbors. Th

R. V. R. Pandya

Human dynamics model consistent with our natural ability to perform different activities is put forward by first arguing limitations of the model suggested by Barabasi (Nature, 435, 207-211, 2005).

Li-Gang Wang, Hong Chen, Nian-Hua Liu, Shi-Yao Zhu

We consider the lateral shift of a light beam reflecting from a dielectric slab backed by a metal. It is found that the lateral shift of the reflected beam can be negative while the intensity of reflected beam is almost equal to the incident one under a certain condition. The explanation for the negativity of the lateral shift is given in terms of the interf

Enrico Rubiola

The close-in AM noise is often neglected, under the assumption that it is a minor problem as compared to phase noise. With the progress of technology and of experimental science, this assumption is no longer true. Yet, information in the literature is scarce or absent. This report describes the measurement of the AM noise of rf/microwave sources in terms of

T. Verechtchaguina, I. M. Sokolov, L. Schimansky-Geier

Motivated by the dynamics of resonant neurons we discuss the properties of the first passage time (FPT) densities for nonmarkovian differentiable random processes. We start from an exact expression for the FPT density in terms of an infinite series of integrals over joint densities of level crossings, and consider different approximations based on truncation

Mario J. Pinheiro

We present a self-consistent two-dimensional fluid model of the temporal and spatial development of the One Atmosphere Uniform Glow Discharge Plasma (OAUGDP$^{\circledR}$). Continuity equations for electrically charged species N$_2^+$, N$_4^+$, O$_2^+$, O$_2^-$ and electrons are solved coupled to the Poisson equation, subject to appropriate boundary conditio

Maria K. Koleva

Exerting fluctuations is a part of our daily life: traffic noise, heartbeat, opinion poll, currency exchange rate, electrical current, chemical reactions - they all permanently fluctuate. One of the most important questions is why the systems that exert fluctuations stay long-term stable. Is there any general functional relation that provides long-term stabi

C. H. Choi, A. Usheva, G. Kalosakas, K. O. Rasmussen

Comment on T.S. van Erp, S. Cuesta-Lopez, J.-G. Hagmann, and M. Peyrard, Phys. Rev. Lett. 95, 218104 (2005) [arXiv: physics/0508094].

Olexandr G. Rasin, Peter E. Hydon

All three-point and five-point conservation laws for the discrete Korteweg-de Vries equations are found. These conservation laws satisfy a functional equation, which we solve by reducing it to a system of partial differential equations. Our method uses computer algebra intensively, because the determining functional equation is quite complicated.

Juan Belmonte-Beitia, Victor M. Perez-Garcia, Vadym Vekslerchik

In this paper we study a system of coupled nonlinear Schrodinger equations modelling a quantum degenerate mixture of bosons and fermions. We analyze the stability of plane waves, give precise conditions for the existence of solitons and write explicit solutions in the form of periodic waves. We also check that the solitons observed previously in numerical si

Jiri Patera

New continuous group transforms, together with their discretization over a lattice of any density and admissible symmetry, are defined for a general compact simple Lie groups of rank $2\leq n<\infty$. Rank 1 transforms are known. Rank 2 exposition of $C$- and $S$-transforms is in the literature. The $E$-transforms appear here for the first time.

Nicole Heymans, Igor Podlubny

On a series of examples from the field of viscoelasticity we demonstrate that it is possible to attribute physical meaning to initial conditions expressed in terms of Riemann-Liouville fractional derivatives, and that it is possible to obtain initial values for such initial conditions by appropriate measurements or observations.

Tharaka A. Lamahewa, Rodney A. Kennedy, Thushara D. Abhayapala, Terence Betlehem

This paper presents an analytical model for the fading channel correlation in general scattering environments. In contrast to the existing correlation models, our new approach treats the scattering environment as non-separable and it is modeled using a bi-angular power distribution. The bi-angular power distribution is parameterized by the mean departure and

Yoshihito Shimada

In this paper, we give the white noise calculus for the Fermion system and prove the Fock expansion. Each continuous linear operator on Fermionic white noise functionals is uniquely represented by the series of integral kernel operators. This series is called the Fock expansion.

Jun Hu

In this paper we study the branching problems for Hecke algebra $\H(D_n)$ of type $D_n$. We explicitly describe the decompositions of the socle of the restriction of each irreducible $\H(D_n)$-representation to $\H(D_{n-1})$ into irreducible modules by using the corresponding results for type $B$ Hecke algebras. In particular, we show that any such restricti

Y. A. Bahturin, S. K. Sehgal, M. V. Zaicev

Let $R$ be a finite-dimensional algebra over an algebraically closed field $F$ graded by an arbitrary group $G$. We prove that $R$ is a graded division algebra if and only if it is isomorphic to a twisted group algebra of some finite subgroup of $G$. If the characteristic of $F$ is zero or ${\rm char} F$ does not divide the order of any finite subgroup of $G

Youri Davydov, Ilya Molchanov, Sergei Zuyev

Using the LePage representation, a strictly stable random element in a Banach space with $α\in(0,2)$ can be represented as a sum of points of a Poisson process. This point process is union-stable, i.e. the union of its two independent copies coincides in distribution with the rescaled original point process. These concepts makes sense in any convex cone, i.e

Romain Abraham, Jean-Francois Delmas

We consider the exploration process associated to the continuous random tree (CRT) built using a Levy process with no negative jumps. This process has been studied by Duquesne, Le Gall and Le Jan. This measure-valued Markov process is a useful tool to study CRT as well as super-Brownian motion with general branching mechanism. In this paper we prove this pro

Claudio Pisani

Some basic features of the simultaneous inclusion of discrete fibrations and discrete opfibrations on a category A in the category of categories over A are studied; in particular, the reflections and the coreflections of the latter in the former are considered, along with a negation-complement operator which, applied to a discrete fibration, gives a functor

Mathieu Dutour Sikiric, Viatcheslav Grishukhin

Roughly speaking, the rank of a Delaunay polytope (first introduced in \cite{DGL92}) is its number of degrees of freedom. In \cite{DL}, a method for computing the rank of a Delaunay polytope $P$ using the hypermetrics related to $P$ is given. Here a simpler more efficient method, which uses affine dependencies instead of hypermetrics is given. This method is

Livio Flaminio, Giovanni Forni

Let X be a vector field on a compact connected manifold M. An important question in dynamical systems is to know when a function g:M -> R is a coboundary for the flow generated by X, i.e. when there exists a function f: M->R such that Xf=g. In this article we investigate this question for nilflows on nilmanifolds. We show that there exists countably many ind

Manuel Blickle, Hélène Esnault, Kay Rülling

The purpose of this survey is to explain some recent results about analogies between characteristic 0 and characteristic $p>0$ geometry, and to discuss an infinitesimal variant of motivic cohomology. More specifically, we review results showing that the big de Rham Witt complex of a field is a complex of 0-cycles (section 2), as well as results showing analo

Yun Gao, Shikui Shang

It is well-known that the second homology group $H_2(\st)$ of the Steinberg Lie algebra $\st$ is trivial when $n\geq 5$. In this paper, we will work out $H_2(\st)$ explicitly for $n=3, 4$ which are not necessarily trivial. Consequently, we obtained $H_2(sl_n(R))$ for $n=3, 4$.

Weiping Yin, Liyou Zhang

The explicit complete Einstein-Kähler metric on the second type Cartan-Hartogs domain $Y_{II}(r,p;K)$ is obtained in this paper when the parameter $K$ equals $\frac p2+\frac 1{p+1}$. The estimate of holomorphic sectional curvature under this metric is also given which intervenes between $-2K$ and $-\frac{2K}p$ and it is a sharp estimate. In the meantime we a

Mark Gross, Simone Pavanelli

We calculate the Brauer group of a certain Calabi-Yau threefold discovered by Mark Gross and Sorin Popescu, which is a small resolution of a complete intersection of type (2,2,2,2) with 64 ordinary double points. We find the Brauer group is (Z/8Z)^2, which is the largest known example of a Brauer group of a Calabi-Yau threefold.

V. Kurlin, D. Lines

Johnson and Livingston have characterized peripheral structures in homomorphs of knot groups. We extend their approach to the case of links. The main result is an algebraic characterization of all possible peripheral structures in certain homomorphic images of link groups.

Y. A. Bahturin, M. V. Zaicev

In this paper we describe all group gradings by a finite abelian group G of any Lie algebra L of the type &#34;A&#34; over algebraically closed field F of characteristic zero.

Atanas Iliev, Laurent Manivel

Let X be a general complex Fano threefold of genus 8. We prove that the moduli space of rank two semistable sheaves on X with Chern numbers c_1=1, c_2=6 and c_3=0 is isomorphic to the Fano surface F(X) of conics on X. Inside F(X), the non-locally free sheaves are parameterized by a smooth curve of genus 26 isomorphic to the base of the family of lines on X.