March 2006 arXiv papers — page 19

Leonid Frankfurt, Mark Strikman

We argue that in the small x processes, in the black disc QCD regime (BDR) a very forward parton propagating through the nuclear matter should loose a significant and increasing with energy and atomic number fraction of its initial energy as a result of dominance of inelastic interactions, causality and energy-momentum conservation. We evaluate these energy

Michel Cristofol, Patricia Gaitan, Hichem Ramoul

For a two by two reaction-diffusion system on a bounded domain we give a simultaneous stability result for one coefficient and for the initial conditions. The key ingredient is a global Carleman-type estimate with a single observation acting on a subdomain.

E. Pian, P. A. Mazzali, N. Masetti, P. Ferrero

Long-duration gamma-ray bursts (GRBs) are associated with type Ic supernovae that are more luminous than average and that eject material at very high velocities. Less-luminous supernovae were not hitherto known to be associated with GRBs, and therefore GRB-supernovae were thought to be rare events. Whether X-ray flashes - analogues of GRBs, but with lower lu

Laila Alabidi, David H. Lyth

The survey of models in astro-ph/0510441 is updated.For the first time, a large fraction of the models is ruled out at more than $3σ$.

F. A. Bovino, M. Giardina, K. Svozil, V. Vedral

We implemented the protocol of entanglement assisted orientation in the space proposed by Brukner et al (quant-ph/0603167). We used min-max principle to evaluate the optimal entangled state and the optimal direction of polarization measurements which violate the classical bound.

Leonardo A. Pachon, José D. Sanabria-Gómez

Recently Kordas (1995, Class. Quantum Grav. 12 2037) and Meinel and Neugebauer (1995, Class. Quantum Grav. 12 2045) studied the conditions for reflection symmetry in stationary axisymmetric space--times in vacuum. They found that a solution to the Einstein field equations is reflectionally symmetric if their Ernst's potential ${\cal E}(ρ=0,z)= e(z)$ on a

D. C. Cabra, M. Moliner, F. Stauffer

We investigate a simple model of a frustrated classical spin chain coupled to adiabatic phonons under an external magnetic field. A thorough study of the magnetization properties is carried out both numerically and analytically. We show that already a moderate coupling with the lattice can stabilize a plateau at 1/3 of the saturation and discuss the deformat

Anna N. Morozovska, Eugene A. Eliseev, Maya D. Glinchuk

Ferroelectric nanoparticles of different shape and their nanocomposites are actively studied in modern physics. Because of their applications in many fields of nanotechnology, the size effects and the possible disappearance of ferroelectricity at a critical particle volume attract a growing scientific interest. In this paper we study the size effects of the

Zhi-Wei Sun, Daqing Wan

Let $p$ be a prime, and let $n>0$ and $r$ be integers. In this paper we study Fleck's quotient $$F_p(n,r)=(-p)^{-\lfloor(n-1)/(p-1)\rfloor} \sum_{k=r(mod p)}\binom {n}{k}(-1)^k\in Z.$$ We determine $F_p(n,r)$ mod $p$ completely by certain number-theoretic and combinatorial methods; consequently, if $2\le n\le p$ then $$\sum_{k=1}^n(-1)^{pk-1}\binom{pn-1}

A. S. Fruchter, A. J. Levan, L. Strolger, P. M. Vreeswijk

When massive stars exhaust their fuel they collapse and often produce the extraordinarily bright explosions known as core-collapse supernovae. On occasion, this stellar collapse also powers an even more brilliant relativistic explosion known as a long-duration gamma-ray burst. One would then expect that long gamma-ray bursts and core-collapse supernovae shou

Florian Dubath, Maria Alice Gasparini, Ruth Durrer

We investigate microlensing in the case where the lens is considered as an extended object. We use a multipolar expansion of the lens potential and show that the time-varying nature of the quadrupole contribution allows to separate it from the mass and spin contributions and leads to specific modulations of the amplification signal. As example we study the c

T. Papenbrock, Z. Pluhar, H. A. Weidenmueller

Introducing sets of constraints, we define new classes of random-matrix ensembles, the constrained Gaussian unitary (CGUE) and the deformed Gaussian unitary (DGUE) ensembles. The latter interpolate between the GUE and the CGUE. We derive a sufficient condition for GUE-type level repulsion to persist in the presence of constraints. For special classes of cons

Francis N. C. Paraan, J. P. Esguerra

We present a continuous time generalization of a random walk with complete memory of its history [Phys. Rev. E 70, 045101(R) (2004)] and derive exact expressions for the first four moments of the distribution of displacement when the number of steps is Poisson distributed. We analyze the asymptotic behavior of the normalized third and fourth cumulants and id

Walter H. Aschbacher

The von Neumann entropy density of a block of n spins is proved to be non-zero for large n in the non-equilibrium steady state of the XY chain constructed by coupling a finite cutout of the chain to the two infinite parts to its left and right which act as thermal reservoirs at different temperatures. Moreover, the non-equilibrium density is shown to be stri

Adam M. Goyt

Klazar defined and studied a notion of pattern avoidance for set partitions, which is an analogue of pattern avoidance for permutations. Sagan considered partitions which avoid a single partition of three elements. We enumerate partitions which avoid any family of partitions of a 3-element set as was done by Simion and Schmidt for permutations. We also consi

Neil D. Christensen, Robert Shrock

We construct extended technicolor (ETC) models that can produce the large splitting between the masses of the $t$ and $b$ quarks without necessarily excessive contributions to the $ρ$ parameter or to neutral flavor-changing processes. These models make use of two different ETC gauge groups, such that left- and right-handed components of charge $Q=2/3$ quarks

Sabine Jansen, Mary-Beth Ruskai, Ruedi Seiler

We present straightforward proofs of estimates used in the adiabatic approximation. The gap dependence is analyzed explicitly. We apply the result to interpolating Hamiltonians of interest in quantum computing.

Rainer Beck

Total magnetic fields in spiral galaxies, as observed through their total synchrotron emission, are strongest (up to \simeq 30\mu G) in the spiral arms. The degree of radio polarization is low; the field in the arms must be mostly turbulent or tangled. Polarized synchrotron emission shows that the resolved regular fields are generally strongest in the intera

James Barton, Mathieu Stienon

We introduce the notion of twisted generalized complex submanifolds and describe an equivalent characterization in terms of Poisson-Dirac submanifolds. Our characterization recovers a result of Vaisman. An equivalent characterization is also given in terms of spinors. As a consequence, we show that the fixed locus of an involution preserving a twisted genera

Vasily Pestun

A two-dimensional topological sigma-model on a generalized Calabi-Yau target space $X$ is defined. The model is constructed in Batalin-Vilkovisky formalism using only a generalized complex structure $J$ and a pure spinor $ρ$ on $X$. In the present construction the algebra of $Q$-transformations automatically closes off-shell, the model transparently depends

G. Annino, M. Cassettari, M. Martinelli

The confinement properties of the open structure formed crossing a circular waveguide perpendicular to a parallel-plate waveguide are discussed, highlighting the fundamental differences with respect to the common high-frequency resonators. Among the electromagnetic modes trapped at the intersection region of the two waveguides, the TE011 one appears as the m

Dmytro Gavinsky, Julia Kempe, Ronald de Wolf

We study the power of quantum fingerprints in the simultaneous message passing (SMP) setting of communication complexity. Yao recently showed how to simulate, with exponential overhead, classical shared-randomness SMP protocols by means of quantum SMP protocols without shared randomness ($Q^\parallel$-protocols). Our first result is to extend Yao's simulatio

Eli Eisenberg, Asher Baram

For a large class of repulsive interaction models, the Mayer cluster integrals can be transformed into a tridiagonal symmetric matrix, whose elements converge to a constant with a 1/n^2 correction. We find exact expressions, in terms of these correction terms, for the two critical exponents describing the density near the two singular termination points of t

H. T. Lu, Y. J. Wang, Shaojin Qin, T. Xiang

Properties of the zigzag spin chains with various nearest-neighbor and next-nearest-neighbor interactions are studied by making use of the transfer-matrix renormalization group method. Thermodynamic quantities of the systems (temperature dependence of the susceptibility and the specific heat), as well as the field dependence of the magnetization are analyzed

Yves Stalder, Alain Valette

We prove that the properties of acting metrically properly on some space with walls or some CAT(0) cube complex are closed by taking the wreath product with \Z. We also give a lower bound for the (equivariant) Hilbert space compression of H\wr\Z in terms of the (equivariant) Hilbert space compression of H.

F. F. Goryayev, A. M. Urnov, L. A. Vainshtein

The wavelengths and radiative transition probabilities for transitions 2lnl'-1snl", 2lnl'-1s2l", 1s2lnl'-1s^2.nl", 1s2lnl'-1s^2.2l", and the autoionization decay probabilities for doubly excited states 2lnl', 1s2lnl' were calculated in ions with atomic numbers Z=6-36 for n=2-10, l'=0-3. The calculations were carrie

Asher Yahalom, Donald Lynden-Bell

We introduce a three independent functions variational formalism for stationary and non-stationary barotropic flows. This is less than the four variables which appear in the standard equations of fluid dynamics which are the velocity field $\vec v$ and the density $\rho$. It will be shown how in terms of our new variable the Euler and continuity equations ca

Yahya Ould Hamidoune, Oriol Serra, Gilles Zemor

We obtain critical pair theorems for subsets S and T of an abelian group such that |S+T| < |S|+|T|+1. We generalize some results of Chowla, Vosper, Kemperman and a more recent result due to Rodseth and one of the authors.

Recai Erdem

A more conventional realization of a symmetry which had been proposed towards the solution of cosmological constant problem is considered. In this study the multiplication of the coordinates by the imaginary number $i$ in the literature is replaced by the multiplication of the metric tensor by minus one. This realization of the symmetry as well forbids a bul

Thomas Curtright, Luca Mezincescu, David Schuster

We discuss supersymmetric biorthogonal systems, with emphasis given to the periodic solutions that occur at spectral singularities of PT symmetric models. For these periodic solutions, the dual functions are associated polynomials that obey inhomogeneous equations. We construct in detail some explicit examples for the supersymmetric pairs of potentials V_{+/

Thierry Lambert, Florence Despetis, Laurent Puech, Pierre-Etienne Wolf

We report on thermodynamic and optical measurements of the condensation process of $^4$He in two silica aerogels of same porosity 95%, but different microstructures resulting from different pH during synthesis. For a base-catalyzed aerogel, the temperature dependence of the shape of adsorption isotherms and of the morphology of the condensation process show

A. A. Saharian, A. S. Tarloyan

Wightman function, the vacuum expectation values of the field square and the energy-momentum tensor are investigated for a massive scalar field with general curvature coupling parameter in the region between two coaxial cylindrical boundaries. It is assumed that the field obeys general Robin boundary conditions on bounding surfaces. The application of a vari

Romeo Brunetti, Klaus Fredenhagen

The recent formulation of locally covariant quantum field theory may open the way towards a background independent perturbative formulation of Quantum Gravity.

Roland Bacher

We prove an inequality of the form $γ_n\geq C_n(γ_{n-1})$ giving a lower bound for the Hermite constant $γ_n$ in dimension $n$ in terms of $γ_{n-1}$. Iterating this inequality yields a new proof of the Minkowski-Hlawka bound.

Tako Mattik

We construct branes in the plane wave background under the inclusion of fermionic boundary fields. The resulting deformed boundary conditions in the bosonic and fermionic sectors give rise to new integrable and supersymmetric branes of type (n,n). The extremal case of the spacetime filling (4,4)-brane is shown to be maximally spacetime supersymmetric.

Nir Bar-Gill, Rami Pugatch, Eitan Rowen, Nadav Katz

We study theoretically a BEC loaded into an optical lattice in the tight-binding regime, with a second, weak incommensurate lattice acting as a perturbation. We find, using direct diagonalization of small systems and a large scale, number conserving Gutzwiller-based mean field approach, the phase diagram of the model. We show that the superfluid, Mott-insula

Bindusar Sahoo, Ashoke Sen

Using the entropy function formalism we compute the entropy of extremal supersymmetric and non-supersymmetric black holes in N=2 supergravity theories in four dimensions with higher derivative corrections. For supersymmetric black holes our results agree with all previous analysis. However in some examples where the four dimensional theory is expected to ari

C. Karrasch, T. Enss, V. Meden

We investigate the effect of local Coulomb correlations on electronic transport through a variety of coupled quantum dot systems connected to Fermi liquid leads. We use a newly developed functional renormalization group scheme to compute the gate voltage dependence of the linear conductance, the transmission phase, and the dot occupancies. A detailed derivat

Zhibing Li, Weiliang Wang

We derived the analytic solution of induced electrostatic potential along single wall carbon nanotubes. Under the hypothesis of constant density of states in the charge-neutral level, we are able to obtain the linear density of excess charge in an external field parallel to the tube axis.

Franz Wegner

Explicit solutions of the two-dimensional floating body problem (bodies that can float in all positions) for relative density rho different from 1/2 and of the tire track problem (tire tracks of a bicycle, which do not allow to determine, which way the bicycle went) are given, which differ from circles. Starting point is the differential equation given in ar

A. Imparato, L. Peliti

We consider a driven Brownian particle, subject to both conservative and non-conservative applied forces, whose probability evolves according to the Kramers equation. We derive a general fluctuation relation, expressing the ratio of the probability of a given Brownian path in phase space with that of the time-reversed path, in terms of the entropy flux to th

F. Cornu, J. Piasecki

We derive the exact solution of the Boltzmann kinetic equation for the three-dimensional Lorentz model in the presence of a constant and uniform magnetic field. The velocity distribution of the electrons reduces exponentially fast to its spherically symmetric component. In the long time hydrodynamic limit there remains only the diffusion process governed by

Kazuki Nakanishi, Macoto Kikuchi

We investigate aggregation mechanism of two proteins in a thermodynamically unambiguous manner by considering the finite size effect of free energy landscape of HP lattice protein model. Multi-Self-Overlap-Ensemble Monte Carlo method is used for numerical calculations. We find that a dimer can be formed spontaneously as a thermodynamically stable state when

Sebastian Bustingorry, Jose Luis Iguain, Claudio Chamon, Leticia F. Cugliandolo

We study the fluctuations of the two-time dependent global roughness of finite size elastic lines in a quenched random environment. We propose a scaling form for the roughness distribution function that accounts for the two-time, temperature, and size dependence. At high temperature and in the final stationary regime before saturation the fluctuations are as

Yutaka Baba, Nobuyuki Ishibashi, Koichi Murakami

We construct BRST invariant solitonic states in the OSp invariant string field theory for closed bosonic strings. Our construction is a generalization of the one given in the noncritical case. These states are made by using the boundary states for D-branes, and can be regarded as states in which D-branes or ghost D-branes are excited. We calculate the vacuum

S. V. Sazonov, N. V. Ustinov

The propagation of the transverse-longitudinal acoustic pulses through a strained cubic crystal containing the resonant paramagnetic impurities with effective spin S=1 is investigated. It is supposed that the pulses propagate under arbitrary angle with respect to the direction of the external static deformation parallel to the fourth-order symmetry axis. In

Roland Steinbauer, James A. Vickers

In this paper we review the extent to which one can use classical distribution theory in describing solutions of Einstein&#39;s equations. We show that there are a number of physically interesting cases which cannot be treated using distribution theory but require a more general concept. We describe a mathematical theory of nonlinear generalised functions ba

Volodymyr Mazorchuk, Serge Ovsienko, Catharina Stroppel

The paper studies quadratic and Koszul duality for modules over positively graded categories. Typical examples are modules over a path algebra, which is graded by the path length, of a not necessarily finite quiver with relations. We present a very general definition of quadratic and Koszul duality functors backed up by explicit examples. This generalises pr

Sang-Bum Lee, Jeong-Bo Shim, Sang Wook Kim, Juhee Yang

Efficient nonresonant optical pumping of a high-Q scar mode in a two-dimensional quadrupole-deformed microlaser has been demonstrated based on ray and wave chaos. Three-fold enhancement in the lasing power was achieved at a properly chosen pumping angle. The experimental result is consistent with ray tracing and wave overlap integral calculations.

S. Capozziello, V. F. Cardone, A. - Troisi

We investigate the possibility that the observed flatness of the rotation curves of spiral galaxies is not an evidence for the existence of dark matter haloes, but rather a signal of the breakdown of General Relativity. To this aim, we consider power - law fourth order theories of gravity obtained by replacing the scalar curvature $R$ with $f(R) = f_0 R^n$ i

Fabien Alet, Gregoire Misguich, Vincent Pasquier, Roderich Moessner

Phase transitions occupy a central role in physics, due both to their experimental ubiquity and their fundamental conceptual importance. The explanation of universality at phase transitions was the great success of the theory formulated by Ginzburg and Landau, and extended through the renormalization group by Wilson. However, recent theoretical suggestions h

T. Paananen, J. -P. Martikainen, P. Torma

We consider pairing in a three-component gas of degenerate fermions. In particular, we solve the finite temperature mean-field theory of an interacting gas for a system where both interaction strengths and fermion masses can be unequal. At zero temperature we find a a possibility of a quantum phase transition between states associated with pairing between di

Christian Lundkvist, Roy Skjelnes

Let X be a scheme that does not satisfy the valuative criterion of separatedness. We show that the Hilbert functor parametrizing closed families of X that are flat, finite and of rank one is not represented by a scheme or an algebraic space.

Sejoong Kim, Hyun-Woo Lee

A pioneering experiment [E. Schuster, E. Buks, M. Heiblum, D. Mahalu, V. Umansky, and Hadas Shtrikman, Nature 385, 417 (1997)] reported the measurement of the transmission phase of an electron traversing a quantum dot and found the intriguing feature of a sudden phase drop in the conductance valleys. Based on the Friedel sum rule for a spinless effective one

Satoshi Ishizaka

A strong entanglement monotone, which never increases under local operations and classical communications (LOCC), restricts quantum entanglement manipulation more strongly than the usual monotone since the usual one does not increase on average under LOCC. We propose new strong monotones in mixed-state entanglement manipulation under LOCC. These are related

C. Capan, L. Balicas, T. P. Murphy, E. C. Palm

We report a high field investigation (up to 45 T) of the metamagnetic transition in CeIrIn$_5$ with resistivity and de-Haas-van-Alphen (dHvA) effect measurements in the temperature range 0.03-1 K. As the magnetic field is increased the resistivity increases, reaches a maximum at the metamagnetic critical field, and falls precipitously for fields just above t

Martin W. Zwierlein, Wolfgang Ketterle

We argue that it is not possible to infer from the results of Partridge et al. (Reports, 27 January 2006, p. 503) which of their data was taken in the superfluid or normal regime, and which of their clouds are phase-separated and which are not. Some of the conclusions in this paper are inconsistent with recent experiments.

Jonathan P. Shock, Feng Wu

Building on recent research into five-dimensional holographic models of QCD, we extend this work by including the strange quark with an SU(3)_L\times SU(3)_R gauge symmetry in the five-dimensional theory. In addition we deform the naive $AdS$ metric with a single parameter, thereby breaking the conformal symmetry at low energies. The vector and axial vector

Shunsuke Takagi

We introduce a new variant of tight closure and give an interpretation of adjoint ideals via this tight closure. As a corollary, we prove that a log pair $(X,Δ)$ is plt if and only if the modulo $p$ reduction of $(X,Δ)$ is divisorially F-regular for all large $p \gg 0$. Here, divisorially F-regular pairs are a class of singularities in positive characteristi

Daniel C. Cohen, F. R. Cohen, Stratos Prassidis

Poly-free groups are constructed as iterated semidirect products of free groups. The class of poly-free groups includes the classical pure braid groups, fundamental groups of fiber-type hyperplane arrangements, and certain subgroups of the automorphism groups of free groups. The purpose of this article is to compute centralizers of certain natural Lie subalg

D. Fargion, M. Grossi

A list of questions regarding Gamma Ray Bursts (GRBs) and Soft Gamma Repeaters (SGRs) remain unanswered within the Fireball-cone and Magnetar explosive scenarios. A persistent, thin (less than micron-sr solid angle) precessing and spinning gamma jet, with a power output comparable to the progenitor supernova (SN) or XRay pulsar, may explain these issues. The

Hiromi Otsuka, Yutaka Okabe, Kiyohide Nomura

We investigate the triangular-lattice antiferromagnetic Ising model with a spatially anisotropic next-nearest-neighbor ferromagnetic coupling, which was first discussed by Kitatani and Oguchi. By employing the effective geometric factor, we analyze the scaling dimensions of the operators around the Berezinskii-Kosterlitz-Thouless (BKT) transition lines, and

Anton A. Klyachko

Adding two generators and one arbitrary relator to a nontrivial torsion-free group, we always obtain an SQ-universal group. In the course of the proof of this theorem, we obtain some other results of independent interest. For instance, adding one generator and one relator in which the exponent sum of the additional generator is one to a free product of two n

R. de la Madrid

The analytic continuation of the Lippmann-Schwinger bras and kets is obtained and characterized. It is shown that the natural mathematical setting for the analytic continuation of the solutions of the Lippmann-Schwinger equation is the rigged Hilbert space rather than just the Hilbert space. It is also argued that this analytic continuation entails the impos

R. de la Madrid

We exemplify the way the rigged Hilbert space deals with the Lippmann-Schwinger equation by way of the spherical shell potential. We explicitly construct the Lippmann-Schwinger bras and kets along with their energy representation, their time evolution and the rigged Hilbert spaces to which they belong. It will be concluded that the natural setting for the so

Lucie Bartuskova, Antonin Cernoch, Radim Filip, Jaromir Fiurasek

We have devised an optical scheme for the recently proposed protocol for encoding two qubits into one qutrit. In this protocol, Alice encodes an arbitrary pure product state of two qubits into a state of one qutrit. Bob can then restore error-free any of the two encoded qubit states but not both of them simultaneously. We have successfully realized this sche

Claudio Garola, Sandro Sozzo

The term proposition usually denotes in quantum mechanics (QM) an element of (standard) quantum logic (QL). Within the orthodox interpretation of QM the propositions of QL cannot be associated with sentences of a language stating properties of individual samples of a physical system, since properties are nonobjective in QM. This makes the interpretation of p

GianCarlo Ghirardi, Luca Marinatto

We generalize Hardy&#39;s proof of nonlocality to the case of bipartite mixed statistical operators, and we exhibit a necessary condition which has to be satisfied by any given mixed state $σ$ in order that a local and realistic hidden variable model exists which accounts for the quantum mechanical predictions implied by $σ$. Failure of this condition will i

P. Caban, J. Rembielinski, K. A. Smolinski, Z. Walczak

We find the time evolution of the system of two non-interacting unstable particles, distinguishable as well as identical ones, in arbitrary reference frame having only the Kraus operators governing the evolution of its components in the rest frame. We than calculate in the rigorous way Einstein-Podolsky-Rosen quantum correlation functions for K0-K0 system in

G. Chiribella, G. M. D&#39;Ariano

We characterize the extremal points of the convex set of quantum measurements that are covariant under a finite-dimensional projective representation of a compact group, with action of the group on the measurement probability space which is generally non-transitive. In this case the POVM density is made of multiple orbits of positive operators, and, in the c

Jinhyoung Lee, Seung-Woo Lee, M. S. Kim

We generalize Greenberger-Horne-Zeilinger (GHZ) nonlocality to every even-dimensional and odd-partite system. For the purpose we employ concurrent observables that are incompatible and nevertheless have a common eigenstate. It is remarkable that a tripartite system can exhibit the genuinely high-dimensional GHZ nonlocality.

Luca Dall&#39;Asta, Alain Barrat, Marc Barthelemy, Alessandro Vespignani

In real networks complex topological features are often associated with a diversity of interactions as measured by the weights of the links. Moreover, spatial constraints may as well play an important role, resulting in a complex interplay between topology, weight, and geography. In order to study the vulnerability of such networks to intentional attacks, th

Hye-Young Kim, Jorge O. Sofo, Darrell Velegol, Milton W. Cole

The fully retarded dispersion interaction between an atom and a cluster or between two clusters is calculated. Results obtained with two different methods are compared. One is to consider a cluster as a collection of many atoms and evaluate the sum of two-body and three-body interatomic interactions, a common assumption. The other method, valid at large sepa

F. Pedaci, S. Lepri, S. Balle, G. Giacomelli

We analyze theoretically and experimentally the influence of current noise on the longitudinal mode hopping dynamics of a bulk semiconductor laser. It is shown that the mean residence times on each mode have different sensitivity to external noise added to the bias current. In particular, an increase of the noise level enhances the residence time on the long

T. Kishimoto, H. Hachisu, J. Fujiki, K. Nagato

Three dimensional electrodynamic trapping of neutral atoms has been demonstrated. By applying time-varying inhomogeneous electric fields with micron-sized electrodes, nearly $10^2$ strontium atoms in the $^1S_0$ state have been trapped with a lifetime of 80 ms. In order to design the electrodes, we numerically analyzed the electric field and simulated atomic

Sanjay M Wagh

The power-point presentation \cite{ppt} provided herein shows exactly why Einstein&#39;s field equations of his general relativity are based on an illogical approach to representing the observable world. Einstein had, in fact, discarded these equations way back in 1928 when he had began his solitary search for a unified field theory. However, the rest of us

S. M. Plis, J. S. George, S. C. Jun, J. Pare-Blagoev

We propose a new model for approximating spatiotemporal noise covariance for use in MEG/EEG source analysis. Our model is an extension of an existing model [1,2] that uses a single Kronecker product of a pair of matrices - temporal and spatial covariance; we employ a series of Kronecker products in order to construct a better approximation of the full covari

A. N. Antonov, M. V. Ivanov, M. K. Gaidarov, E. Moya de Guerra

The scaling function $f(ψ&#39;)$ for medium and heavy nuclei with $Z\neq N$ for which the proton and neutron densities are not similar is constructed within the coherent density fluctuation model (CDFM) as a sum of the proton and neutron scaling functions. The latter are calculated in the cases of $^{62}$Ni, $^{82}$Kr, $^{118}$Sn, and $^{197}$Au nuclei on th

A. L. Cole, H. Akimune, Sam M. Austin, D. Bazin

Electron capture and beta decay play important roles in the evolution of pre-supernovae stars and their eventual core collapse. These rates are normally predicted through shell-model calculations. Experimentally determined strength distributions from charge-exchange reactions are needed to test modern shell-model calculations. We report on the measurement of

Roldao da Rocha, Jayme Vaz,

This paper is intended to investigate Grassmann and Clifford algebras over Peano spaces, introducing their respective associated extended algebras, and to explore these concepts also from the counterspace viewpoint. The exterior (regressive) algebra is shown to share the exterior (progressive) algebra in the direct sum of chiral and achiral subspaces. The du

Janusz Grabowski, Marek Kus, Giuseppe Marmo

We address several problems concerning the geometry of the space of Hermitian operators on a finite-dimensional Hilbert space, in particular the geometry of the space of density states and canonical group actions on it. For quantum composite systems we discuss and give examples of measures of entanglement.

Roldao da Rocha, E. Capelas de Oliveira

This work is intended to investigate the geometry of anti-de Sitter spacetime (AdS), from the point of view of the Laplacian Comparison Theorem (LCT), and to give another description of the hyperbolical embedding standard formalism of the de Sitter and anti-de Sitter spacetimes in a pseudo-Euclidean spacetime. It is shown how to reproduce some geometrical pr

Kazuo Akutagawa, Luis A. Florit, Jimmy Petean

For a closed Riemannian manifold $(M^m,g)$ of constant positive scalar curvature and any other closed Riemannian manifold $(N^n,h)$, we show that the limit of the Yamabe constants of the Riemannian products $(M\times N,g+rh)$ as $r$ goes to infinity is equal to the Yamabe constant of $(M^m \times R^n, [g+g_E])$ and is strictly less than the Yamabe invariant

Manfred Einsiedler

We give a relatively short and self contained proof of Ratner&#39;s theorem in the special case of SL(2,R)-invariant measures.

Jason Bandlow, Gregg Musiker

Let $s_{ij}$ represent a tranposition in $S_n$. A polynomial $P$ in $\mathbb{Q}[X_n]$ is said to be $m$-quasiinvariant with respect to $S_n$ if $(x_i-x_j)^{2m+1}$ divides $(1-s_{ij})P$ for all $1 \leq i, j \leq n$. We call the ring $m$-quasiinvariants $QI_m[X_n]$. We describe a method for constructing a basis for the quotient $QI_m[X_3]/< e_1, e_2, e_3>$. Th

Lucia Caporaso, Eduardo Esteves

We construct Abel maps for a stable curve $X$. Namely, for each one-parameter deformation of $X$ with regular total space, and every integer $d>0$, we construct by specialization a map $α^d_X$ from the smooth locus of $X^d$ to the moduli scheme of balanced line bundles on semistable curves over $X$. For $d=1$, we show that $α^1_X$ naturally extends over $X$,

Lorenzo Zambotti

We consider stochastic differential equations in a Hilbert space, perturbed by the gradient of a convex potential. We investigate the problem of convergence of a sequence of such processes. We propose applications of this method to reflecting O.U. processes in infinite dimension, to stochastic partial differential equations with reflection of Cahn-Hilliard t

G. S. Asanov

We formulate the notion of the Finsleroid--Finsler space, including the positive--definite as well as indefinite cases. The associated concepts of angle, scalar product, and the distance function are elucidated. If the Finsleroid--Finsler space is of Landsberg type, then the Finsleroid charge is a constant. The Finsleroid--Finsler space proves to be a Berwal

Daniel C. Cohen, Peter Orlik

This paper is a survey of our work based on the stratified Morse theory of Goresky and MacPherson. First we discuss the Morse theory of Euclidean space stratified by an arrangement. This is used to show that the complement of a complex hyperplane arrangement admits a minimal cell decomposition. Next we review the construction of a cochain complex whose cohom

Melvyn B. Nathanson

The Caccetta-Haggkvist conjecture states that if G is a finite directed graph with at least n/k edges going out of each vertex, then G contains a directed cycle of length at most k. Hamidoune used methods and results from additive number theory to prove the conjecture for Cayley graphs and for vertex-transitive graphs. This expository paper contains a survey

Kenneth L. Baker

The braid axis of a closed 3-braid lifts to a genus one fibered knot in the double cover of S^3 branched over the closed braid. Every (null homologous) genus one fibered knot in a 3-manifold may be obtained in this way. Using this perspective we answer a question of Morimoto about the number of genus one fibered knots in lens spaces. We determine the number

Yiannis Petridis, Morten S. Risager

We investigate how often geodesics have homology in a fixed set of the homology lattice of a compact Riemann surface. We prove that closed geodesics are equidistributed on any sets with asymptotic density with respect to a specific norm. We explain the analogues for free groups, conjugacy classes and discrete logarithms, in particular, we investigate the den

A. V. Knyazev, M. E. Argentati

Many inequality relations between real vector quantities can be succinctly expressed as &#34;weak (sub)majorization&#34; relations. We explain these ideas and apply them in several areas: angles between subspaces, Ritz values, and graph Laplacian spectra, which we show are all surprisingly related... An application of our Ritz values weak majorization result

Gabriele Link

Let X be a Hadamard manifold and $Γ$ a discrete group of isometries of X which contains an axial isometry without invariant flat half plane. We study the behavior of conformal densities on the geometric limit set of $Γ$ in order to derive a new asymptotic estimate for the growth rate of closed geodesics in not necessarily compact or finite volume manifolds.

Christian Hillmann, Axel Kleinschmidt, Hermann Nicolai

We explain how to achieve the traceless gauge for the spatial part of the spin connection in the framework of the recently proposed correspondence between the (appropriately truncated) bosonic sectors of maximal supergravities and the `geodesic&#39; sigma-model over E10/K(E10) at low levels. After making this gauge choice, the residual symmetries on both sid

Klaus Fredenhagen, Karl-Henning Rehren, Erhard Seiler

We comment on the present status, the concepts and their limitations, and the successes and open problems of the various approaches to a relativistic quantum theory of elementary particles, with a hindsight to questions concerning quantum gravity and string theory.

Avinash Dhar, Gautam Mandal

We use the recently developed tools for an exact bosonization of a finite number $N$ of non-relativistic fermions to discuss the classic Tomonaga problem. In the case of noninteracting fermions, the bosonized hamiltonian naturally splits into an O$(N)$ piece and an O$(1)$ piece. We show that in the large-N and low-energy limit, the O$(N)$ piece in the hamilt

Hidenori Sonoda

The general prescription for constructing the continuum limit of a field theory is explained using Wilson&#39;s renormalization group. We then formulate the renormalization group in perturbation theory and apply it to the four dimensional phi4 theory and QED.

E. I. Guendelman, A. B. Kaganovich

We study the scalar sector of the Two Measures Field Theory (TMT) model in the context of cosmological dynamics. The scalar sector includes the inflaton ϕand the Higgs \upsilon fields. The model possesses gauge and scale invariance. The latter is spontaneously broken due to intrinsic features of the TMT dynamics. In the model with the inflaton ϕalone, in dif

P. A. Horvathy

The ``exotic&#39;&#39; particle model with non-commuting position coordinates, associated with the two-parameter central extension of the planar Galilei group, can be used to derive the ground states of the Fractional Quantum Hall Effect. The relation to other NC models is discussed. Anomalous coupling is presented. Similar equations arise for a semiclassica