December 2006 arXiv papers — page 26
Showing 2,501–2,600 of 4,461 papers
Valerie R. Coffman, James P. Sethna, Gerd Heber, Mu Liu
Intergranular fracture in polycrystals is often simulated by finite elements coupled to a cohesive-zone model for the interfaces, requiring cohesive laws for grain boundaries as a function of their geometry. We discuss three challenges in understanding intergranular fracture in polycrystals. First, 3D grain boundary geometries comprise a five dimensional spa
Randomized and Quantum Solution of Initial-Value Problems for Ordinary Differential Equations of Order k
quant-phMarek Szczesny
We study possible advantages of randomized and quantum computing over deterministic computing for scalar initial-value problems for ordinary differential equations of order k. For systems of equations of the first order this question has been settled modulo some details in \cite{Kacewicz05}. A speed-up over deterministic computing shown in \cite{Kacewicz05}
Johan Wulleman
It is generally accepted that the disturbance interpretation cannot explain Heisenberg's uncertainty relation DxDp=h. In this paper a clear distinction will be made between the notions of state preparation and measurement, noting that the disturbance that is referred to in Heisenberg's disturbance interpretation is usually caused by the measurement.
Otfried Gühne, Norbert Lütkenhaus
Entanglement witnesses provide a standard tool for the analysis of entanglement in experiments. We investigate possible nonlinear entanglement witnesses from several perspectives. First, we demonstrate that they can be used to show that the set of separable states has no facets. Second, we give a new derivation of nonlinear witnesses based on covariance matr
N. Timoney, V. Elman, W. Neuhauser, Chr. Wunderlich
Coherent operations constitutive for the implementation of single and multi-qubit quantum gates with trapped ions are demonstrated that are robust against variations in experimental parameters and intrinsically indeterministic system parameters. In particular, pulses developed using optimal control theory are demonstrated for the first time with trapped ions
Anisotropically high entanglement of biphotons generated in spontaneous parametric down conversion
quant-phM. V. Fedorov, M. A. Efremov, P. A. Volkov, E. V. Moreva
We show that the wave packet of a biphoton generated via spontaneous parametric down conversion is strongly anisotropic. Its anisotropic features manifest themselves very clearly in comparison of measurements performed in two different schemes: when the detector scanning plane is perpendicular or parallel to the plane containing the crystal optical axis and
C. Schoen, K. Hammerer, M. M. Wolf, J. I. Cirac
We study the sequential generation of entangled photonic and atomic multi-qubit states in the realm of cavity QED. We extend the work of C. Schoen et al. [Phys. Rev. Lett. 95, 110503 (2005)], where it was shown that all states generated in a sequential manner can be classified efficiently in terms of matrix-product states. In particular, we consider two scen
Akira kitagawa, Masahiro Takeoka, Masahide Sasaki, Anthony Chefles
We show that the Fisher information associated with entanglement-assisted coding has a monotonic relationship with the logarithmic negativity, an important entanglement measure, for certain classes of continuous variable (CV) quantum states of practical significance. These are the two-mode squeezed states and the non-Gaussian states obtained from them by pho
Sungho Hong, Blaise Aguera y Arcas, Adrienne L. Fairhall
White noise methods are a powerful tool for characterizing the computation performed by neural systems. These methods allow one to identify the feature or features that a neural system extracts from a complex input, and to determine how these features are combined to drive the system's spiking response. These methods have also been applied to characteriz
C. Caretta Cartozo, D. Garlaschelli, C. Ricotta, M. Barthelemy
We analyze several florae (collections of plant species populating specific areas) in different geographic and climatic regions. For every list of species we produce a taxonomic classification tree and we consider its statistical properties. We find that regardless of the geographical location, the climate and the environment all species collections have uni
Caglar Tuncay
Time evolutions of number of cities, population of cities, world population, and size distribution of present languages are studied in terms of a new model, where population of each city increases by a random rate and decreases by a random division. World population and size distribution of languages come out in good agreement with the available empirical da
Caglar Tuncay
May randomness (real numbers, opinions) evolve into order (regularity) with time? We study some polarization and symmetry properties, which emerge in time evolution of opinions (real numbers) within entries of two and three-dimensional lattices, which had initial randomness.
R. Chicireanu, Q. Beaufils, A. Pouderous, B. Laburthe-Tolra
We experimentally and theoretically study the continuous accumulation of cold atoms from a magneto-optical trap (MOT) into a finite depth trap, consisting in a magnetic quadrupole trap dressed by a radiofrequency (RF) field. Chromium atoms (52 isotope) in a MOT are continuously optically pumped by the MOT lasers to metastable dark states. In presence of a RF
K. P. Zybin, V. A. Sirota, A. S. Ilyin, A. V. Gurevich
The Navier-Stokes equation for incompressible liquid is considered in the limit of infinitely large Reynolds number. It is assumed that the flow instability leads to generation of steady-state large-scale pulsations. The excitation and evolution of the small-scale turbulence is investigated. It is shown that the developed small-scale pulsations are intermitt
Erez Etzion, David Primor, Giora Mikenberg, Nir Amram
The new particle accelerators and its experiments create a challenging data processing environment, characterized by large amount of data where only small portion of it carry the expected new scientific information. Modern detectors, such as the Cathode Strip Chamber (CSC), achieve high accuracy of coordinate measurements (between 50 to 70 microns). However,
S. P. Gabuda, S. G. Kozlova, V. V. Panov, E. O. Golenkov
We consider the problem of mobility and localization of hydrogen atoms in the Te(OH)6 crystals. The model of particles moving in a rapidly oscillating field was used.
Thomas Mueller, Andreas King, Daria Adis
In principle, the twin paradox offers the possibility to go on a trip to the center of our galaxy or even to the end of our universe within life time. In order to be a most comfortable journey the voyaging twin accelerates with Earth's gravity. We developed some Java applets to visualize what both twins could really measure, namely time signals and light
F. Grüner, S. Becker, U. Schramm, T. Eichner
A recent breakthrough in laser-plasma accelerators, based upon ultrashort high-intensity lasers, demonstrated the generation of quasi-monoenergetic GeV-electrons. With future Petawatt lasers ultra-high beam currents of ~100 kA in ~10 fs can be expected, allowing for drastic reduction in the undulator length of free-electron-lasers (FELs). We present a discus
S L Yakovlev, C-Y Hu, D Caballero
A problem to account for the direct electron-positron annihilation in positron-hydrogen scattering above the positronium formation threshold has been resolved within the time independent formalism. The generalization of the optical theorem is derived for the case when an absorption potential is present in the Hamiltonian. With this theorem the annihilation c
Dylan Walker, Huafeng Xie, Koon-Kiu Yan, Sergei Maslov
To account for strong aging characteristics of citation networks, we modify Google's PageRank algorithm by initially distributing random surfers exponentially with age, in favor of more recent publications. The output of this algorithm, which we call CiteRank, is interpreted as approximate traffic to individual publications in a simple model of how resea
Filipi Nascimento Silva, Luciano da Fontoura Costa
The possibility to identify the nature (e.g. random or scale free) of complex networks while performing respective random walks is investigated with respect to autonomous agents based on Bayesian decision theory and humans navigating through a graphic-interactive interface. The results indicate that the type of the network (choice between random and scale fr
Eric Brown, Guenter Ahlers
A model for the large-scale circulation (LSC) dynamics of turbulent Rayleigh-Benard convection is presented. It consists of two stochastic ordinary differential equations motivated by the Navier-Stokes equation, one each for the strength and the azimuthal orientation of the LSC. Stochastic forces represent phenomenologically the action of the turbulent fluct
The Role of the Gouy Phase in the Coherent Phase Control of the Photoionization and Photodissociation of Vinyl Chloride
physics.chem-phVishal J. Barge, Zhan Hu, Joyce Willig, Robert J. Gordon
We demonstrate theoretically and experimentally that the Gouy phase of a focused laser beam may be used to control the photo-induced reactions of a polyatomic molecule. Quantum mechanical interference between one- and three-photon excitation of vinyl chloride produces a small phase lag between the dissociation and ionization channels on the axis of the molec
Michael Courtney, Amy Courtney
This article describes measurement of potato cannon velocity with a digitized microphone signal. A microphone is attached to the potato cannon muzzle and a potato is fired at an aluminum target about 10 m away. The potato's flight time can be determined from the acoustic waveform by subtracting the time in the barrel and time for sound to return from the
A Model for Predicting Magnetic Targeting of Multifunctional Particles in the Microvasculature
physics.bio-phE. J. Furlani, E. P. Furlani
A mathematical model is presented for predicting magnetic targeting of multifunctional carrier particles that are designed to deliver therapeutic agents to malignant tissue in vivo. These particles consist of a nonmagnetic core material that contains embedded magnetic nanoparticles and therapeutic agents such as photodynamic sensitizers. For in vivo therapy,
J. Mitroy, M. W. J. Bromley
A simple way to generate low energy phase shifts for elastic scattering using bound-state calculations is postulated, validated and applied to the problem of e+ - Mg scattering. The essence of the method is to use the energy shift between a small reference calculation and the largest possible calculation of the lowest energy pseudo-state to tune a semi-empir
On the resonance spectra of particle-unstable light nuclei with a Sturmian approach that preserves the Pauli principle
nucl-thL. Canton, K. Amos, S. Karataglidis, G. Pisent
The fundamental ingredients of the MCAS (multi-channel algebraic scattering) method are discussed. The main feature, namely the application of the sturmian theory for nucleon-nucleus scattering, allows solution of the scattering problem given the phenomenological ingredients necessary for the description of weakly-bound (or particle-unstable) light nuclear s
Aswini Kumar Rath, Z Naik, C R Praharaj
The origin of the identical gamma-ray energies (IB) observed in the K=33/2$^+$ and K=16$^+$ bands in $^{177}$Lu and $^{178}$Hf respectively is investigated using deformed Hartree-Fock and Angular Momentum Projection technique. We find that quantised orbital (rather than spin) alignment of protons in the m=1/2$^+$ inert orbit leads to identical energy spectra
Janardan P. Singh, Frank X. Lee
The mass spectra of strange baryons in the octet family are investigated in a finite-energy QCD sum rule approach based on the Gauss-Weierstrass transform. The phenomenological form of the spectral function is saturated by the ground state and two of the lowest excited states, considered as having opposite parities. Treating the ground state parameters as kn
Extended Optical Model Analyses of Elastic Scattering and Fusion Cross Sections for 6Li + 208Pb System at Near-Coulomb-Barrier Energies by using Folding Potential
nucl-thW. Y. So, T. Udagawa, K. S. Kim, S. W. Hong
Based on the extended optical model approach in which the polarization potential is decomposed into direct reaction (DR) and fusion parts, simultaneous $χ^{2}$ analyses are performed for elastic scattering and fusion cross section data for the $^{6}$Li+$^{208}$Pb system at near-Coulomb-barrier energies. A folding potential is used as the bare potential. It i
Final-state interactions and superscaling in the semi-relativistic approach to quasielastic electron and neutrino scattering
nucl-thJ. E. Amaro, M. B. Barbaro, J. A. Caballero, T. W. Donnelly
The semi-relativistic approach to electron and neutrino quasielastic scattering from nuclei is extended to include final-state interactions. Starting with the usual non-relativistic continuum shell model, the problem is relativized by using the semi-relativistic expansion of the current in powers of the initial nucleon momentum and relativistic kinematics. T
Statistical Properties of Nonlinear Shell Models of Turbulence from Linear Advection Models: Rigorous Results
nlin.CDRoberto Benzi, Boris Levant, Itamar Procaccia, Edriss S. Titi
In a recent paper it was proposed that for some nonlinear shell models of turbulence one can construct a linear advection model for an auxiliary field such that the scaling exponents of all the structure functions of the linear and nonlinear fields coincide. The argument depended on an assumption of continuity of the solutions as a function of a parameter. T
Yohei Tutiya
A previously unknown bright N-soliton solution for an intermediate nonlinear Schrödinger equation of focusing type is presented. This equation is constructed as a reduction of an integrable system related to a Sato equation of a 2-component KP hierarchy for certain differential--difference dispersion relations. Bright soliton solutions are obtained in the fo
Chiara Manzini, Giovanni Frosali
The asymptotic analysis of a linear high-field Wigner-BGK equation is developped by a modified Chapman-Enskog procedure. By an expansion of the unknown Wigner function in powers of the Knudsen number $ε$, evolution equations are derived for the terms of zeroth and first order in $ε$. In particular, it is obtained a quantum drift-diffusion equation for the po
Alexandre Eremenko, Andrei Gabrielov, Boris Shapiro
We study eigenfunctions of Schrodinger operators -y"+Py on the real line with zero boundary conditions, whose potentials P are real even polynomials with positive leading coefficients. For quartic potentials we prove that all zeros of all eigenfunctions belong to the union of the real and imaginary axes. Similar result holds for sextic potentials and the
Francisco Nettel, Hernando Quevedo
We present a derivation of the energy spectrum of the harmonic oscillator by using the alternative approach of topological quantization. The spectrum is derived from the topological invariants of a particular principal fiber bundle which can be assigned to any configuration of classical mechanics, when formulated according to Maupertuis formalism.
Moulay Rchid Sidi Ammi, Delfim F. M. Torres
We study a system of nonlinear partial differential equations resulting from the traditional modelling of oil engineering within the framework of the mechanics of a continuous medium. Recent results on the problem provide existence, uniqueness and regularity of the optimal solution. Here we obtain the first necessary optimality conditions.
Ion I. Dinca
Confocal quadrics capture (encode) and geometrize spectral properties of symmetric operators. Certain metric-projective properties of confocal quadrics (most of them established in the first half of the XIX$^{\mathrm{th}}$ century) {\it carry out} (stick and transfer) by rolling to and influence surfaces {\it applicable} (isometric) to quadrics and surfaces
Yunhi Cho, Hyuk Kim
We consider the projectivization of Minkowski space with the analytic continuation of the hyperbolic metric and call this an extended hyperbolic space. We can measure the volume of a domain lying across the boundary of the hyperbolic space using an analytic continuation argument. In this paper we show this method can be further generalized to find the volume
Gerard Ben Arous, Veronique Gayrard, Alexey Kuptsov
We introduce here a new universality conjecture for levels of random Hamiltonians, in the same spirit as the local REM conjecture made by S. Mertens and H. Bauke. We establish our conjecture for a wide class of Gaussian and non-Gaussian Hamiltonians, which include the $p$-spin models, the Sherrington-Kirkpatrick model and the number partitioning problem. We
M. Kapranov, E. Vasserot
We relate the gerbe of sheaves of chiral differential operators (CDO) on a algebraic variety X, studied by Gorbounov, Malikov and Schechtman, to the determinantal gerbe of the formal loop space LX introduced in our earlier paper. The liens of the two gerbes are related by a version of the symplectic action homomorphism. The determinantal gerbe of LX has a fa
Distributions that are convolvable with generalized Poisson kernel of solvable extensions of homogeneous Lie groups
math.CAEwa Damek, Jacek Dziubanski, Philippe Jaming, Salvador Pérez-Esteva
In this paper, we characterize the class of distributions on an homogeneous Lie group $\fN$ that can be extended via Poisson integration to a solvable one-dimensional extension $\fS$ of $\fN$. To do so, we introducte the $ß'$-convolution on $\fN$ and show that the set of distributions that are $ß'$-convolvable with Poisson kernels is precisely the se
Philippe Jaming
In this paper we prove that there exists a constant $C$ such that, if $S,Σ$ are subsets of $\R^d$ of finite measure, then for every function $f\in L^2(\R^d)$, $$\int_{\R^d}|f(x)|^2 dx \leq C e^{C \min(|S||Σ|, |S|^{1/d}w(Σ), w(S)|Σ|^{1/d})} (\int_{\R^d\setminus S}|f(x)|^2 dx + \int_{\R^d\setminusΣ}|\hat{f}(x)|^2 dx) $$ where $\hat{f}$ is the Fourier transform
Antongiulio Fornasiero
Let X be a definable sub-set of some o-minimal structure. We study the spectrum of X, in relation with the definability of types.
Christian houdré, Trevis J. Litherland
Let $X_1, X_2, ..., X_n, ... $ be a sequence of iid random variables with values in a finite alphabet $\{1,...,m\}$. Let $LI_n$ be the length of the longest increasing subsequence of $X_1, X_2, ..., X_n.$ We express the limiting distribution of $LI_n$ as functionals of $m$ and $(m-1)$-dimensional Brownian motions. These expressions are then related to simila
Violeta Petkova
A Wiener-Hopf operator on a Banach space of functions on R+ is a bounded operator T such that P^+S_{-a}TS_a=T, for every positive a, where S_a is the operator of translation by a. We obtain a representation theorem for the Wiener-Hopf operators on a large class of functions on R+ with values in a separable Hilbert space.
Martin Weimann
In the spirit of a theorem of Wood, we give necessary and sufficient conditions for a family of germs of analytic hypersurfaces in a smooth projective toric variety X to be interpolated by an algebraic hypersurface with a fixed class in the Picard group of X.
Dorota Mozyrska, Zbigniew Bartosiewicz
Systems of germs of sets in infinite-dimensional spaces are introduced and studied. Such a system corresponds to a local zero-set of an ideal of the ring of analytic functions of infinite number of variables. Conversely, this system of germs defines the ideal of germs of analytic functions vanishing on it. A theorem of zeros is proved, stating that this idea
J. Fernandez Bonder, N. Saintier
In this paper we find estimates for the optimal constant in the critical Sobolev trace inequality $S\|u\|^p_{L^{p_*}(\partialΩ) \hookrightarrow \|u\|^p_{W^{1,p}(Ω)}$ that are independent of $Ω$. This estimates generalized those of [3] for general $p$. Here $p_* := p(N-1)/(N-p)$ is the critical exponent for the immersion and $N$ is the space dimension. Then w
Friedrich Haslinger, Bernhard Lamel
We study boundedness, compactness, and Schatten-class membership of the canonical solution operator to dbar, restricted to (0,1)-forms with holomorphic coefficients, on L^2(d mu) where mu is a measure with the property that the monomials form an orthogonal family in L^2 (d mu). The characterizations are formulated in terms of moment properties of mu. Our res
Saharon Shelah, Alex Usvyatsov
We deal with the systematic development of stability for the context of approximate elementary submodels of a monster metric space, which is not far, but still very distinct from the first order case. In particular we prove the analogue of Morley's theorem for the classes of complete metric spaces.
Pavol Severa
The procedure "Lie group --> Lie algebra" has a generalization "simplicial manifold --> L_infinity algebra", or yet better, "presheaf on the category of surjective submersions --> L_infinity algebra". We describe this generalization, together with its higher-order extensions.
Wolfgang Krieger
A property $(D)$ of subshifts was defined in: Wolfgang Krieger, On $g$-functions for subshifts, IMS Lecture Notes- Monograph Series, Vol. 48, Dynamics & Stochastics (2006) 306 - 316, arXiv:math.DS/0608259. With a view towards a theory of $g$-fnctions beyond the case of finte type subshifts partially defined continuous $g$-functions of property $(D)$ subshift
T. Harima, J. Watanabe
Let A be a standard graded Artinian algebra over a field of characteristic zero and let z be a linear form in A. We define the central simple modules for each such pair (A, z). Assume that A is Gorenstein. Then we prove that A has the strong Lefschetz property if and only if there exists a linear form z in A such that all central simple modules of the pair (
Gadadhar Misra, Subrata Shyam Roy
For an operator $T$ in the class ${\mathrm B}_n(Ω)$, introduced in \cite{CD}, the simultaneous unitary equivalence class of the curvature and the covariant derivatives up to a certain order of the corresponding bundle $E_T$ determine the unitary equivalence class of the operator $T$. In the paper \cite{CD2}, the authors ask if there exists some pair of inequ
Yo'av Rieck, Yasushi Yamashita
Given a finite cover f:tilde{G} \to G and an embedding of tilde{G} in the plane, Negami conjectures that G embeds in P^2. Negami proved this conjecture for regular covers. In this paper we define two properties (Propserties V and E), depending on the cover tilde{G} and its embedding into S^2, and generalize Negami's result by showing: (1) If Properties V
Jirô Akahori, Takahiro Tsuchiya
This paper gives examples of explicit arbitrage-free term structure models with Lévy jumps via state price density approach. By generalizing quadratic Gaussian models, it is found that the probability density function of a Lévy process is a "natural" scale for the process to be the state variable of a market.
Florentin Smarandache
In this paper we give two theorems from the Propositional Calculus of the Boolean Logic with their consequences and applications and we prove them axiomatically.
Carlo Hamalainen
In this paper we determine a class of critical sets in the abelian {2--group} that may be obtained from a greedy algorithm. These new critical sets are all 2--critical (each entry intersects an intercalate, a trade of size 4) and completes in a top down manner.
Liqun Wang, Klaus Pötzelberger
We propose an approach to compute the boundary crossing probabilities for a class of diffusion processes which can be expressed as piecewise monotone (not necessarily one-to-one) functionals of a standard Brownian motion. This class includes many interesting processes in real applications, e.g., Ornstein-Uhlenbeck, growth processes and geometric Brownian mot
Michael Bjorklund, Alexander Engstrom
The McMullen Correspondence gives a linear dependence between M-sequences of length |d/2|+1 and f-vectors of simplical d-polytopes. Denote the transfer matrix between g and f by M_d. Recently, Bjorner proved that any 2x2-minor of M_d is nonnegative and conjectured that the same would be true for arbitrary minors. In this paper we answer the question in the a
Y. -L. Ou, Z. -P. Wang
In this paper, we study biharmonic maps into Sol and Nil spaces, two model spaces of Thurston's 3-dimensional geometries. We characterize non-geodesic biharmonic curves in Sol space and prove that there exists no non-geodesic biharmonic helix in Sol space. We also show that a linear map from a Euclidean space into Sol or Nil space is biharmonic if and on
Alessandro Perotti
Let D be a domain in the quaternionic space H. We prove a differential criterion that characterizes Fueter-regular quaternionic functions f:bD -> H of class C^1. We find differential operators T and N, with complex coefficients, such that a function f is regular on D if and only if (N-jT)f=0 on the boundary of D (j a basic quaternion) and f is harmonic on D.
Sadok Kallel, Denis Sjerve
We investigate the action of the automorphism group of a closed Riemann surface on its set of theta characteristics (or spin structures). We give criteria for when an automorphism fixes all spin structures, or when it fixes just one. The case of hyperelliptic curves and of the Klein quartic are discussed in detail.
D. Panyushev, A. Premet, O. Yakimova
Let $g_e$ be the centraliser of a nilpotent element $e$ in a finite dimensional simple Lie algebra $g$ of rank $l$ over an algebraically closed field of characteristic 0. We investigate the algebra $S(g_e)^{g_e}$ of symmetric invariants of $g_e$ and prove that if $g$ is of type $A$ or $C$, then $S(g_e)^{g_e}$ is always a graded polynomial algebra in $l$ vari
Alexander Fel'shtyn, Evgenij Troitsky
For a wide class of groups including polycyclic and finitely generated polynomial growth groups it is proved that the Reidemeister number of an automorphism f is equal to the number of finite-dimensional fixed points of the induced map f^ on the unitary dual, if one of these numbers is finite. This theorem is a natural generalization of the classical Burnsid
Hidden dynamics and the origin of pulsating waves in Self-propagating High temperature Synthesis
math.APR. Monneau, G. S. Weiss
We derive the precise limit of SHS in the high activation energy scaling suggested by B.J. Matkowksy-G.I. Sivashinsky in 1978 and by A. Bayliss-B.J. Matkowksy-A.P. Aldushin in 2002. In the time-increasing case the limit coincides with the Stefan problem for supercooled water {\em with spatially inhomogeneous coefficients}. In general it is a nonlinear forwar
Elisa Gorla
We consider a family of schemes, that are defined by minors of a homogeneous symmetric matrix with polynomial entries. We assume that they have maximal possible codimension, given the size of the matrix and of the minors that define them. We show that these schemes are G-bilinked to a linear variety of the same dimension. In particular, they can be obtained
W. Mueckenheim
The notions of potential infinity (understood as expressing a direction) and actual infinity (expressing a quantity) are investigated. It is shown that the notion of actual infinity is inconsistent, because the set of all (finite) natural numbers which it is ascribed to, cannot contain an actually infinite number of elements. Further the basic inequality of
R. Holman, Laura Mersini-Houghton, Tomo Takahashi
This is the second paper in the series that confronts predictions of a model of the landscape with cosmological observations. We show here how the modifications of the Friedmann equation due to the decohering effects of long wavelength modes on the wavefunction of the Universe defined on the landscape leave unique signatures on the CMB spectra and large scal
V. V. Kozlov, I. V. Volovich
It is suggested that the properties of the mass spectrum of elementary particles could be related with cosmology. Solutions of the Klein-Gordon equation on the Friedmann type manifold with the finite action are constructed. These solutions (actons) have a discrete mass spectrum. We suggest that such solutions could select a universe from cosmological landsca
E. R. Bezerra de Mello, A. A. Saharian
In this paper we calculate the induced electrostatic self-energy and self-force for an electrically charged particle placed at rest in the spacetime of a global monopole admitting a general spherically symmetric inner structure to it. In order to develop this analysis we calculate the three-dimensional Green function associated with this physical system. We
Raffaele Punzi, Frederic P. Schuller, Mattias N. R. Wohlfarth
The Lorentzian spacetime metric is replaced by an area metric which naturally emerges as a generalized geometry in quantum string and gauge theory. Employing the area metric curvature scalar, the gravitational Einstein-Hilbert action is re-interpreted as dynamics for an area metric. Without the need for dark energy or fine-tuning, area metric cosmology expla
Pietro Giudice, Ferdinando Gliozzi, Stefano Lottini
We study the thickness of the confining flux tube generated by a pair of sources in higher representations of the gauge group. Using a simple geometric picture we argue that the area of the cross-section of the flux tube, as measured by a Wilson loop probe, grows logarithmically with source separation, as a consequence of the quantum fluctuations of the unde
Min-xin Huang, Albrecht Klemm, Seth Quackenbush
The topological string partition function Z=exp(lambda^{2g-2} F_g) is calculated on a compact Calabi-Yau M. The F_g fulfill the holomorphic anomaly equations, which imply that Z transforms as a wave function on the symplectic space H^3(M,Z). This defines it everywhere in the moduli space of M along with preferred local coordinates. Modular properties of the
Vadim V. Asadov, Oleg V. Kechkin
It is shown, that parity violation in quantum systems can be a natural result of their dynamical evolution. The corresponding (completely integrable) formalism is based on the use of quantum theory with complex time and non-Hermitian Hamiltonian. It is demonstrated, that starting with total symmetry between left and right states at the initial time, one obta
Vadim V. Asadov, Oleg V. Kechkin
It is shown, that quantum theory with complex evolutionary time parameter and non-Hermitian Hamiltonian structure can be used for natural unification of quantum and thermodynamic principles. The theory is postulated as analytical in respect to the parameter of evolution, which real part is identified with the `usual' physical time, whereas the imaginary
Peter Bowcock, Georgios Tzamtzis
The quantum complex sine-Gordon model on a half line is studied. The quantum spectrum of boundary bound states using the the semi-classical method of Dashen, Hasslacher and Neveu is obtained. The results are compared and found to agree with the bootstrap programme. A particle/soliton reflection factor is conjectured, which is consistent with unitary, crossin
Justin Khoury, Maulik Parikh
Mach's principle is the concept that inertial frames are determined by matter. We propose and implement a precise formulation of Mach's principle in which matter and geometry are in one-to-one correspondence. Einstein's equations are not modified and no selection principle is applied to their solutions; Mach's principle is realized wholly wit
Yui Noma, Toshio Nakatsu, Takeshi Tamakoshi
We present an expression of a deformed partition function for N=2 U(1) gauge theory on C^2/Z_k by using plethystic exponentials.
Panying Chen, Xiangdong Ji
We study the polarized gluon distribution $Δg(x)$ in a longitudinally polarized proton. We argue that the distribution can be calculated approximately from the quark color currents found in simple quark models. The first result from the MIT bag model as well as the non-relativistic quark model shows that $Δg(x)$ is positive at all $x$. If this feature holds
M. R. Schindler, D. Djukanovic, J. Gegelia, S. Scherer
We present the results of a complete two-loop calculation at order q^6 of the nucleon mass in manifestly Lorentz-invariant chiral perturbation theory. The renormalization is performed using the reformulated infrared renormalization, which allows for the treatment of two-loop integrals while preserving all relevant symmetries, in particular chiral symmetry.
J. P. B. C. de Melo, T. Frederico, E. Pace, S. Pisano
An approach for a unified description of the nucleon electromagnetic form factors in spacelike and timelike regions is presented. The main ingredients of our model are: $i)$ a Mandelstam formula for the matrix elements of the nucleon electromagnetic current; $ii)$ a 3-dimensional reduction of the problem on the Light-Front performed within the so-called {\tt
Rasmus Mackeprang, Andrea Rizzi
In this paper we present a physics model for the interactions of stable heavy hadrons containing a heavy parton with matter. The model presented is a natural continuation of the work started in hep-ex/0404001. However, changes and generalisations have been made allowing for the description of a broader scope of physics scenarios. As a special case the model
Study of meson properties in quark models (Ph.D. Thesis, University of Pittsburgh, October 2006)
hep-phOlga Lakhina
The main motivation is to investigate meson properties in the quark model to understand the model applicability and generate possible improvements. Certain modifications to the model are suggested which have been inspired by fundamental QCD properties (such as running coupling or spin dependence of strong interactions). These modifications expand the limits
Alexander Kusenko
Supersymmetric extensions of the Standard Model predict the existence of Q-balls with baryon and lepton numbers. Stable Q-balls can form at the end of inflation from the fragmentation of the Affleck-Dine condensate and can exist as dark matter. The best current limits come from Super-Kamiokande and MACRO. The search beyond these limits can be conducted using
Jose A. R. Cembranos, Jonathan L. Feng, Louis E. Strigari
Minimal universal extra dimensions (mUED) is often thought to predict that the lightest Kaluza-Klein particle (LKP) is the Kaluza-Klein gauge boson B^1, leading to conventional missing energy signals at colliders and WIMP dark matter. In fact, the implications of mUED are far richer: the B^1, charged Higgs boson H^{\pm 1}, and graviton G^1 are all possible L
C. Aubin
We review several results that have been obtained using lattice QCD with the staggered quark formulation. Our focus is on the quantities that have been calculated numerically with low statistical errors and have been extrapolated to the physical quark mass limit and continuum limit using staggered chiral perturbation theory. We limit our discussion to a brie
Han Liu
The PHENIX experiment has measured transverse single spin asymmetry of J/$Ψ$ in polarized p+p collisions at forward rapidity at $\sqrt{s}=200$ GeV. The data were collected from year 2006 run of RHIC with average beam polarization of 56%. At RHIC energy, heavy quark production is dominated by gluon gluon interaction. Therefore, the transverse single spin asym
The FOCUS collaboration
Using a large sample of \dpkkpi{} decays collected by the FOCUS photoproduction experiment at Fermilab, we present the first non-parametric analysis of the \kpi{} amplitudes in \dpkkpi{} decay. The technique is similar to the technique used for our non-parametric measurements of the \krzmndk{} form factors. Although these results are in rough agreement with
Double Helicity Asymmetry and Cross Section for eta Production in Polarized pp Collisions at PHENIX
hep-exFrank Ellinghaus
Measurements of double helicity asymmetries for inclusive hadron production in polarized proton-proton collisions are sensitive to spin-dependent parton distribution functions, in particular to the gluon distribution, Delta g. This study presents the double helicity asymmetry and the cross section for eta production. The cross section measurement yields valu
Elisabetta Gallo
Recent results for direct searches for physics beyond the Standard Model are reviewed. The results include Tevatron II data up to 1.2 fb-1 and HERA results up to 350 pb-1. Searches for Supersymmetry, for compositeness and for large extra dimensions are presented. The excess of events with an isolated lepton and high missing transverse momentum at HERA is dis
László Á. Gergely, Zoltán Keresztes, Balázs Mikóczi
The radial component of the motion of compact binary systems composed of neutron stars and/or black holes on eccentric orbit is integrated. We consider all type of perturbations that emerge up to second post-Newtonian order. These perturbations are either of relativistic origin or are related to the spin, mass quadrupole and magnetic dipole moments of the bi
Compact binary inspiral and the science potential of third-generation ground-based gravitational wave detectors
gr-qcChris Van Den Broeck, Anand S. Sengupta
We consider EGO as a possible third-generation ground-based gravitational wave detector and evaluate its capabilities for the detection and interpretation of compact binary inspiral signals. We identify areas of astrophysics and cosmology where EGO would have qualitative advantages, using Advanced LIGO as a benchmark for comparison.
Leonardo Modesto
In this paper we obtain the black hole metric from a semiclassical analysis of loop quantum black hole. Our solution and the Schwarzschild one tend to match well at large distances from Planck region. In r=0 the semiclassical metric is regular and singularity free in contrast to the classical one. By using the new metric we calculate the Hawking temperature
Aaron V. B. Arellano, Francisco S. N. Lobo
We explore the possibility of dynamic wormhole geometries, within the context of nonlinear electrodynamics. The Einstein field equation imposes a contracting wormhole solution and the obedience of the weak energy condition. Furthermore, in the presence of an electric field, the latter presents a singularity at the throat, however, for a pure magnetic field t
George Jaroszkiewicz
We propose a test of the principle of relativity, involving quantum signals between two inertial frames. If the principle is upheld, classical causality will appear to be split in a dramatic and emphatic way. We discuss the existence of quantum horizons, which are barriers to the transmission of any form of quantum information. These must occur in any finite
Gyula Fodor
Slowly rotating perfect fluid balls with regular center and asymptotically flat exterior are considered to second order in the rotation parameter. The necessary condition for being Petrov type D is given for general perfect fluid matter. As a special case, fluids with a linear equation of state are considered. Using a power series expansion at the regular ce
Lau Loi So
Deser et al. proposed a combination of the Einstein and Landau-Lifshitz pseudotensors such that the second derivatives in vacuum are proportional to the Bel-Robinson tensor. Stimulated by their work, the present paper discuss the gravitational energy-momentum expression which has the same desirable Bel-Robinson tensor property. We find modifications of the E
Sergey Benditkis, Illya Safro
Our theme bases on the classical Hanoi Towers Problem. In this paper we will define a new problem, permitting some positions, that were not legal in the classical problem. Our goal is to find an optimal (shortest possible) sequence of discs' moves. Besides that, we will research all versions of 3-pegs classical problem with some special constraints, when