January 2005 arXiv papers — page 3
Showing 201–300 of 3,506 papers
Extraction of the b-quark shape function parameters using the Belle B->X_s gamma photon energy spectrum
hep-exA. Limosani, T. Nozaki
We determine the b-quark shape function parameters, Lambda^SF and lambda_1^SF using the Belle B->X_s gamma photon energy spectrum. We assume three models for the form of the shape function; Exponential, Gaussian and Roman.
Soumen Basak
We investigate the scattering of phase oscillation of Bose-Einstein Condensate by a 'draining of bathtub' type fluid motion. We derive a relation between the reflection and transmission coefficients which exhibits existence of analog of 'Superradiance effect' in BEC vortex with sink.
Chris Winstead, Anthony Rapley, Vincent C. Gaudet, Christian Schlegel
This paper presents a stochastic algorithm for iterative error control decoding. We show that the stochastic decoding algorithm is an approximation of the sum-product algorithm. When the code's factor graph is a tree, as with trellises, the algorithm approaches maximum a-posteriori decoding. We also demonstrate a stochastic approximations to the alternat
Alexander Shaydurov
In this paper have written the results of the information analysis of structures. The obtained information estimation (IE) are based on an entropy measure of C. Shannon. Obtained IE is univalent both for the non-isomorphic and for the isomorphic graphs, algorithmically, it is asymptotically steady and has vector character. IE can be used for the solution of
Magnetic Field Dependent Behavior of the CDW ground state in Per2M(mnt)2 (M = Au, Pt)
cond-mat.str-elJ. S. Brooks, D. Graf, E. S. Choi, M. Almeida
The Per2M(mnt)2 class of organic conductors exhibit a charge density wave (CDW) ground state below about 12 K, which may be suppressed in magnetic fields of order 20 to 30 T. However, for both cases of counter ion M(mnt)2 species studied (M = Au (zero spin) and M = Pt (spin 1/2)), new high field ground states evolve for further increases in magnetic field. W
Polarization Conversion and "Focusing" of Light Propagating through a Small Chiral Hole in a Metallic Screen
cond-mat.mtrl-sciA. V. Krasavin, A. S. Schwanecke, M. Reichelt, T. Stroucken
Propagation of light through a thin flat metallic screen containing a hole of twisted shape is sensitive to whether the incident wave is left or right circularly polarized. The transmitted light accrues a component with handedness opposite to the incident wave. The efficiency of polarization conversion depends on the mutual direction of the hole's twist
Analytical derivation of lateral pressure profile from microscopic model of lipid bilayer
cond-mat.softSergei I. Mukhin, Svetlana V. Baoukina
Field-theoretical method is proposed, that yields analytical expression for lateral pressure distribution across hydrophobic core of a bilayer lipid membrane. Lipid molecule, repelling entropicaly surrounding neighbors, is modeled as a flexible string embedded between confining walls in the self-consistent harmonic potential. At room temperature the pressure
Fabio Pizzolato Noam Soker
In this paper we push forward and exploit an analogy between the morphologies of the X-ray cavities observed in some galaxy clusters, and the optically deficient point-symmetric bubbles occurring in some planetary nebulae (PNe). Point-symmetric PNe are thought to be shaped by stellar binary interactions; namely, the presence of a companion to the PN's pr
M. S. Dimitrijevic, T. Ryabchikova, L. C. Popovic, D. Shulyak
Using the semiclassical perturbation method, electron-, proton-, and ionized helium-impact line widths and shifts for the nine Cr I spectral lines from the $4p^7P^0-4d^7D$ multiplet, have been calculated for a perturbers density of 10$^{14}$ cm$^{-3}$ and temperatures T =2,500 - 50,000 K. The obtained results have been used to investigate the influence of St
C. N. Hao, X. Y. Xia, Shude Mao, Hong Wu
We study the properties of infrared-selected QSOs (IR QSOs), optically-selected QSOs (PG QSOs) and Narrow Line Seyfert 1 galaxies (NLS1s). We compare their properties from the infrared to the optical and examine various correlations among the black hole mass, accretion rate, star formation rate and optical and infrared luminosities. We find that the infrared
A. Jessner, A. Slowikowska, B. Klein, H. Lesch
Individual giant radio pulses (GRPs) from the Crab pulsar last only a few microseconds. However, during that time they rank among the brightest objects in the radio sky reaching peak flux densities of up to 1500 Jy even at high radio frequencies. Our observations show that GRPs can be found in all phases of ordinary radio emission including the two high freq
Three-dimensional Numerical Simulations of Rayleigh-Taylor Unstable Flames in Type Ia Supernovae
astro-phM. Zingale, S. E. Woosley, C. A. Rendleman, M. S. Day
Flame instabilities play a dominant role in accelerating the burning front to a large fraction of the speed of sound in a Type Ia supernova. We present a three-dimensional numerical simulation of a Rayleigh-Taylor unstable carbon flame, following its evolution through the transition to turbulence. A low Mach number hydrodynamics method is used, freeing us fr
Alberto S. Cattaneo, Giovanni Felder
We prove a relative version of Kontsevich's formality theorem. This theorem involves a manifold M and a submanifold C and reduces to Kontsevich's theorem if C=M. It states that the DGLA of multivector fields on an infinitesimal neighbourhood of C is L-infinity-quasiisomorphic to the DGLA of multidifferential operators acting on sections of the exteri
R. A. Battye, B. Carter, E. Chachoua, A. Moss
Observational evidence suggests that the large scale dynamics of the universe is presently dominated by dark energy, meaning a non-luminous cosmological constituent with a negative value of the pressure to density ratio $w=P/ρ$, which would be unstable if purely fluid, but could be stable if effectively solid with sufficient rigidity. It was suggested by Buc
Bernard de Wit, Henning Samtleben
We describe generalizations of the manifestly E_{6(6)} covariant formulation of five-dimensional gauged maximal supergravity with regard to the structure of the vector and tensor fields. We indicate how the group-theoretical structures that we discover seem to play a role in gauged supergravities in various space-time dimensions.
Laura Molino
Let f be a germ of holomorphic self-map of C^2 at the origin O tangent to the identity, and with O as a non-dicritical isolated fixed point. A parabolic curve for f is a holomorphic f-invariant curve, with O on the boundary, attracted by O under the action of f. It has been shown that if the characteristic direction [v] has residual index not belonging to Q^
Escape configuration lattice near the nematic-isotropic transition: Tilt analogue of blue phases
cond-mat.softBuddhapriya Chakrabarti, Yashodhan Hatwalne, N. V. Madhusudana
We predict the possible existence of a new phase of liquid crystals near the nematic-isotropic ($ NI $) transition. This phase is an achiral, tilt-analogue of the blue phase and is composed of a lattice of {\em double-tilt}, escape-configuration cylinders. We discuss the structure and the stability of this phase and provide an estimate of the lattice paramet
Elizabeth Winstanley
We investigate the possibility of dressing a four-dimensional black hole with classical scalar field hair which is non-minimally coupled to the space-time curvature. Our model includes a cosmological constant but no self-interaction potential for the scalar field. We are able to rule out black hole hair except when the cosmological constant is negative and t
Marzena H. Szymanska, Krzysztof Goral, Thorsten Koehler, Keith Burnett
We use the standard fermionic and boson-fermion Hamiltonians to study the BCS-BEC cross-over near the 202 G resonance in a two-component mixture of fermionic 40K atoms employed in the experiment of C.A. Regal et al., Phys. Rev. Lett. 92, 040403 (2004). Our mean-field analysis of many-body equilibrium quantities shows virtually no differences between the pred
B. M. Barbashov, V. N. Pervushin, A. F. Zakharov, V. A. Zinchuk
The Hamiltonian approach to cosmological perturbations in general relativity in finite space-time is developed, where a cosmological scale factor is identified with spatial averaging the metric determinant logarithm. This identification preserves the number of variables and leads to a cosmological perturbation theory with the scalar potential perturbations i
Michael H. Brügmann
Light deflection in the post-linear gravitational field of two bounded point-like masses is treated. Both the light source and the observer are assumed to be located at infinity in an asymptotically flat space. The equations of light propagation are explicitly integrated to the second order in $G/c^2$. Some of the integrals are evaluated by making use of an
Energy Loss Distribution in the Plane Couette Flow and the Taylor-Couette Flow between Concentric Rotating Cylinders
physics.flu-dynHua-Shu Dou, Boo Cheong Khoo, Khoon Seng Yeo
The distribution of energy loss due to viscosity friction in plane Couette flow and Taylor-Couette Flow between concentric rotating cylinders are studied in detail for various flow conditions. The energy loss is related to the industrial processes in some fluid delivery devices and has significant influence on the flow efficiency, flow stability, turbulent t
Yuval Peres, Gabor Pete, Ariel Scolnicov
An important conjecture in percolation theory is that almost surely no infinite cluster exists in critical percolation on any transitive graph for which the critical probability is less than 1. Earlier work has established this for the amenable cases Z^2 and Z^d for large d, as well as for all non-amenable graphs with unimodular automorphism groups. We show
Shi-Jie Xiong, Shi-Jie Xu
We investigate excitonic polaron states comprising a local exciton and phonons in the longitudinal optical (LO) mode by solving the Schrödinger equation. We derive an exact expression for the ground state (GS), which includes multi-phonon components with coefficients satisfying the Huang-Rhys factors. The recombination of GS and excited polaron states gives
Structure and stability of Mott-insulator shells of bosons trapped in an optical lattice
cond-mat.otherB. DeMarco, C. Lannert, S. Vishveshwara, T. -C. Wei
We consider the feasibility of creating a phase of neutral bosonic atoms in which multiple Mott-insulating states coexist in a shell structure and propose an experiment to spatially resolve such a structure. This spatially-inhomogeneous phase of bosons, arising from the interplay between the confining potential and the short-ranged repulsion, has been previo
Mechanism for nonequilibrium symmetry breaking and pattern formation in magnetic films
cond-mat.otherJ. M. Deutsch, Trieu Mai
Magnetic thin films exhibit a strong variation in properties depending on their degree of disorder. Recent coherent x-ray speckle experiments on magnetic films have measured the loss of correlation between configurations at opposite fields and at the same field, upon repeated field cycling. We perform finite temperature numerical simulations on these systems
Kerstin Hoef-Emden
In molecular phylogeny, relationships among organisms are reconstructed using DNA or protein sequences and are displayed as trees. A linear increase in the number of sequences results in an exponential increase of possible trees. Thus, inferring trees from molecular data was shown to be NP-hard. This causes problems, if large data sets are used. This review
K. A. Bugaev, J. B. Elliott
The surface partition of large clusters is studied analytically within a frame-work of the ``Hills and Dales Model''. Three formulations are solved exactly by using the Laplace-Fourier transformation method. In the limit of small amplitude deformations, the ``Hills and Dales Model'' gives upper and lower bounds for the surface entropy coeffic
Mieczyslaw K. Dabkowski, Makiko Ishiwata, Jozef H. Przytycki
We classify 3-braids up to (2,2)-move equivalence and in particular we show how to adjust the Harikae-Nakanishi-Uchida conjecture so it holds for closed 3-braids. As important steps to classify 3-braids up to (2,2)-move equivalence we prove the conjecture for 2-algebraic links and classify (2,2)-equivalence classes for links up to nine crossings. We analyze
Mitsuhiro Miyazaki
The homogeneous coordinate ring of a Schubert variety (a Schubert cycle for short) is an algebra with straightening law generated by a distributive lattice. This paper gives a simple method to study the set of all the join-irreducible elements of this distributive lattice, and gives a simple proof of the criterion of the Gorenstein property of Schubert cycle
David Pumberger, Tristan Riviere
We prove that tangent cones to 2-dimensional calibrated cycles are unique. Using this result we prove a rate of convergence for the mass of the blow-up of a calibrated integral 2-cycle towards the limiting density. With the same techniques, we can also prove such a rate for J-holomorphic maps between almost complex manifolds and deduce the uniqueness of thei
Stavros Argyrios Papadakis
Type III unprojection plays a very important role in the birational geometry of Fano threefolds. It was first introduced by A. Corti on his calculations of Fano threefolds of genus 6 and 7. It seems that at present a general definition of the type III unprojection is still missing. After proving some general facts about residual ideals, we propose a definiti
Stavros Argyrios Papadakis
Answering a question of M. Reid, we define and prove the Gorensteiness of the type II unprojection.
Taekyun Kim
We give the q-analogue of the sums of the n-th powers of positive integers up to k-1.
N. A. Carella
This paper introduces a general technique for estimating the absolute value of pure Gaussian sums of order k over a prime p for a class of composite order k. The new estimate improves the classical estimate by a factor of about 2 or better (depending on k) for all sufficiently large primes p.
Yu. Chernyakov, V. Dolotin
We define the class of non-decomposable $N$-ary operations in the mixed tensor algebra $\bigoplus\limits_{i,j=0}^\infty A_i^j$. There are higher Jacobi-like identities for (binary) deformed matrix commutator and a 3-ary operation which is non-decomposable into binary ones.
Hugh Thomas
The usual, or type A_n, Tamari lattice is a partial order on T_n^A, the triangulations of an (n+3)-gon. We define a partial order on T_n^B, the set of centrally symmetric triangulations of a (2n+2)-gon. We show that it is a lattice, and that it shares certain other nice properties of the A_n Tamari lattice, and therefore that it deserves to be considered the
Itzhak Bars
We give an overview of the correspondance between one-time-physics and two-time-physics. This is characterized by the presence of an SO(d,2) symmetry and an Sp(2) duality among diverse one-time-physics systems all of which can be lifted to the same more symmetric two-time-physics system by the addition of gauge degrees of freedom. We provide several explicit
R. N. Mohapatra, M. K. Parida, G. Rajasekaran
We consider threshold effects on neutrino masses and mixings in a recently proposed model for understanding large solar and atmospheric mixing angles using radiative magnification for the case of quasi-degenerate neutrinos. We show that the magnitude of the threshold effects is sufficient to bring concordance between the predictions of this model and latest
Manoj Kumar
In 2000, Hwang and Li proposed a remote user authentication scheme using smart cards to solve the problems of Lamport scheme. Later, Chan- Chang, Shen- Lin- Hwang and then Chang-Hwang pointed out some attacks on Hwang – Li’s scheme. In 2003, Shen, Lin and Hwang also proposed a modified scheme to remove these attacks. In the same year, Leung-Cheng
Markus Lazar
We consider dislocations in the framework of Eringen's nonlocal elasticity. The fundamental field equations of nonlocal elasticity are presented. Using these equations, the nonlocal force stresses of a straight screw and a straight edge dislocation are given. By the help of these nonlocal stresses, we are able to calculate the interaction forces between
Melanie Schulte, Caroline Drope
We investigate as a member of the Ising universality class the Next-Nearest Neighbour Ising model without external field on a simple cubic lattice by using the Monte Carlo Metropolis Algorithm. The Binder cumulant and the susceptibility ratio, which should be universal quantities at the critical point, were shown to vary for small negative next-nearest neigh
Santo Fortunato, Dietrich Stauffer
We review the opinion dynamics in the computer models of Deffuant et al. (D), of Krause and Hegselmann (KH), and of Sznajd (S). All these models allow for consensus (one final opinion), polarization (two final opinions), and fragmentation (more than two final opinions), depending on how tolerant people are to different opinions. We then simulate the reaction
F. Kh. Chibirova
Scientific study of the effect of structural memory of nonequilibrium defective solids about the processing in magnetic field (the magnetic structural effect (MSE) was continued in this paper. The study was aimed to reveal the universal nature of the MSE, which was investigated in several new nonequilibrium defective solids. The results of investigation of t
Gerrit E. W. Bauer, Yaroslav Tserkovnyak, Arne Brataas, Jun Ren
The theory of charge and spin transport in forward-biased Schottky barriers reveals characteristic and experimentally relevant features. The conductance mismatch is found to enhance the current induced spin-imbalance in the semiconductor. The GaAs|MnAs interface resistance is obtained from an analysis of the magnetic field dependent Kerr rotation experiments
Kicheon Kang
We investigate the effect of the charge state measurement of the Kondo singlet for a quantum dot transistor via a capacitively coupled quantum point contact detector. By employing the variational ansatz for the singlet ground state of the quantum dot combined with the density matrix formulation for the coupled system, we show that the coherent Kondo singlet
Temperature dependent photon emission spectra of free excitons in phonon field of GaN
cond-mat.mtrl-sciS. J. Xu, G. Q. Li, S. -J. Xiong, C. M. Che
Temperature-dependent radiative recombination of free excitons involving one or two LO phonons in GaN is investigated in detail. It is found that both phonon sidebands possess asymmetric lineshape and their energy spacings from the zero phonon line strongly deviate from the characteristic energy of LO phonons as the temperature increases. Furthermore, the de
Excitonic Polaron States and Fano Interference in Phonon-Assisted Photoluminescence of Bound Excitons in ZnO
cond-mat.mtrl-sciShi-Jie Xu, Shi-Jie Xiong, Shen-Lei Shi
We report a photoluminescence observation of robust excitonic polarons due to strong coupling of exciton and longitudinal optical (LO) phonon as well as Fano-type interference in high quality ZnO crystal. At low enough temperatures, the strong coupling of excitons and LO phonons leads to not only traditional Stokes lines (SLs) but also up to second-order ant
Constantine Yannouleas, Uzi Landman
Calculations for two electrons in an elliptic quantum dot, using symmetry breaking at the unrestricted Hartree-Fock level and subsequent restoration of the broken parity via projection techniques, show that the electrons can localize and form a molecular dimer, described by a Heitler-London-type wave function. The calculated singlet-triplet splitting (J) as
Monwhea Jeng
We study the height one, two, three, and four variables in the Abelian sandpile model. We argue that correlation functions along closed boundaries, as well as general conformal field theory principles, show that the four variables are not represented by the same operator along closed boundaries, or in the bulk. Along open boundaries, we calculate all n-point
D. Froebrich, T. P. Ray, G. C. Murphy, A. Scholz
We present three 14400 square degree relative extinction maps of the Galactic Plane (|b|<20degrees) obtained from 2MASS using accumulative star counts (Wolf diagrams). This method is independent of the colour of the stars and the variation of extinction with wavelength. Stars were counted in 3.5'x3.5' boxes, every 20". 1x1degree surrounding field
D. G. Yakovlev, K. P. Levenfish, O. Y. Gnedin
We discuss pycnonuclear burning of highly exotic atomic nuclei in deep crusts of neutron stars, at densities up to 1e13 g/cc. As an application, we consider pycnonuclear burning of matter accreted on a neutron star in a soft X-ray transient (SXT, a compact binary containing a neutron star and a low-mass companion). The energy released in this burning, while
Xiao-fei Zhang, Hong Li, Yun-Song Piao, Xinmin Zhang
In this paper, we study the possibility of building two-field models of dark energy with equation of state across -1. Specifically we will consider two classes of models: one consists of two scalar fields (Quintessence+Phantom) and another includes one scalar (Phantom) and one spinor field (Neutrino). Our studies indicate to some extent that two-field models
The Stable Topology of the Planetary Systems of two 2:1 Resonant Companions:Application to HD 82943
astro-phJi Jianghui, H. Kinoshita, Liu Lin, H. Nakai
We have numerically explored the stable planetary geometry for the multiple systems involved in a 2:1 mean motion resonance, and herein we mainly study the HD 82943 system by employing two sets of the orbital parameters (Mayor et al. 2004; Ji et al. 2004). In the simulations, we find that all stable orbits are related to the 2:1 resonance that can help to re
An 8.5 GHz Arecibo survey of Carbon Recombination Lines toward Ultra-compact \HII regions: Physical properties of dense molecular material
astro-phD. Anish Roshi, Dana. S. Balser, T. M. Bania, W. M. Goss
We report here on a survey of carbon recombination lines (RLs) near 8.5 GHz toward 17 ultra-compact \HII regions (\UCHII s). Carbon RLs are detected in 11 directions, indicating the presence of dense photodissociation regions (PDRs) associated with the \UCHII s. In this paper, we show that the carbon RLs provide important, complementary information on the ki
Srikumar M. Menon, D. Anish Roshi, T. Rajendra Prasad
We present the results of a search for the ground state hyperfine transition of the OH radical near 53 MHz using the National MST Radar Facility at Gadanki, India. The observed position was G48.4$-$1.4 near the Galactic plane. The OH line is not detected. We place a 3$σ$ upper limit for the line flux density at 39 Jy from our observations. We also did not de
Jacco Vink
In this review I discuss the various gamma-ray emission lines that are expected and have been observed from radioactive explosive nucleosynthesis products. The most important gamma-ray lines result from the decay chains of Ni-56, Ni-57, and Ti-44. Ni-56 is the prime explosive nucleosynthesis product of Type Ia supernovae, but Ni-56 is also a product of core-
Noam Soker
An increasing amount of literature reports the detection of magnetic fields in asymptotic giant branch (AGB) stars and in central stars of planetary nebulae (PNs). These detections lead to claims that the magnetic fields are the main agent shaping the PNs. In this paper, I examine the energy and angular momentum carried by magnetic fields expelled from AGB s
Ilarion V. Melnikov, M. Ronen Plesser
We investigate toric GLSMs as models for tachyon condensation in type II strings on space-time non-supersymmetric orbifold singularities. The A-model correlators in these theories satisfy a set of relations related to the topology of the resolved orbifold. Using these relations we compute the correlators and find a non-trivial chiral ring in the IR, which we
Celia Anteneodo, Raul O. Vallejos
The Hamiltonian Mean-Field model (HMF), an inertial XY ferromagnet with infinite-range interactions, has been extensively studied in the last few years, especially due to its long-lived meta-equilibrium states, which exhibit a series of anomalies, such as, breakdown of ergodicity, anomalous diffusion, aging, and non-Maxwell velocity distributions. The most w
Oliver Henkel
A new design method for high rate, fully diverse ('spherical') space frequency codes for MIMO-OFDM systems is proposed, which works for arbitrary numbers of antennas and subcarriers. The construction exploits a differential geometric connection between spherical codes and space time codes. The former are well studied e.g. in the context of optimal se
W. T. Lu, S. Sridhar
We derive a general theory for imaging by a flat lens without optical axis. We show that the condition for imaging requires a material having elliptic dispersion relations with negative group refraction, equivalent to an effective anisotropic refractive index n(theta). Imaging can be achieved with both negative (n<0) and positive (n>0) refractive indices. Th
Dmitri Kharzeev, Kirill Tuchin
The number of gluons in the hadron wave function is discrete, and their formation in the chain of small $x$ evolution occurs over discrete rapidity intervals of $Δy \simeq 1/\as$. We therefore consider the evolution as a discrete quantum process. We show that the discrete version of the mean-field Kovchegov evolution equation gives rise to strong fluctuation
Michael L. Graesser, Alejandro Jenkins, Mark B. Wise
Lorentz-violating operators involving Standard Model fields are tightly constrained by experimental data. However, bounds are more model-independent for Lorentz violation appearing in purely gravitational couplings. The spontaneous breaking of Lorentz invariance by the vacuum expectation value of a vector field selects a universal rest frame. This affects th
Anders Johansen, Hubert Klahr
We measure the turbulent diffusion coefficient of dust grains embedded in magnetorotational turbulence in a protoplanetary disc directly from numerical simulations and compare it to the turbulent viscosity of the flow. The simulations are done in a local coordinate frame comoving with the gas in Keplerian rotation. Periodic boundary conditions are used in al
The scaling limit of the correlation of holes on the triangular lattice with periodic boundary conditions
math-phMihai Ciucu
We define the correlation of holes on the triangular lattice under periodic boundary conditions and study its asymptotics as the distances between the holes grow to infinity. We prove that the joint correlation of an arbitrary collection of lattice-triangular holes of even sides satisfies, for large separations between the holes, a Coulomb law and a superpos
M. I. Baznat, S. G. Mashnik, K. K. Gudima, R. E. Prael
An improved version of the Cascade-Exciton Model (CEM) of nuclear reactions contained in the code CEM2k and the Los Alamos version of the Quark-Gluon String Model (LAQGSM) are merged with the well-known sequential-binary-decay model GEMINI by Charity. We present some results on proton-induced fragmentation, fission-product yields and on particle spectra pred
Ricardo Gallego Torromé
We consider specific deterministic quantum models of Cartan-Randers type and show how a dualized abelian gauge symmetry, diffeomorphism invariance, the Principle of Inertia, reversibility of phenomenological dynamics, maximal acceleration and maximal propagation speed for matter arise from such models in an phenomenological description. Two particular predic
Zeng-Bing Chen, Qiang Zhang, Xiao-Hui Bao, J. Schmiedmayer
We propose a novel double-entanglement-based quantum cryptography protocol that is both efficient and deterministic. The proposal uses photon pairs with entanglement both in polarization and in time degrees of freedom; each measurement in which both of the two communicating parties register a photon can establish one and only one perfect correlation and thus
Gorjan Alagic, Alexander Russell
We study a natural notion of decoherence on quantum random walks over the hypercube. We prove that in this model there is a decoherence threshold beneath which the essential properties of the hypercubic quantum walk, such as linear mixing times, are preserved. Beyond the threshold, we prove that the walks behave like their classical counterparts.
V. V. Kabanov, J. Demsar, D. Mihailovic
Superconducting state dynamics following excitation of a superconductor with a femtosecond optical pulse is studied in terms of a phenomenological Rothwarf and Taylor model. Analytical solutions for various limiting cases are obtained. The model is found to account for the intensity and temperature dependence of both photoinduced quasiparticle density, as we
Sergei Alexandrov, Zoltan Kadar
We construct a canonical formulation of general relativity for the case of a timelike foliation of spacetime. The formulation possesses explicit covariance with respect to Lorentz transformations in the tangent space. Applying the loop approach to quantize the theory we derive the spectrum of the area operator of a two-dimensional surface. Its different bran
David Brown
Einstein's theory of general relativity is written in terms of the variables obtained from a conformal--traceless decomposition of the spatial metric and extrinsic curvature. The determinant of the conformal metric is not restricted, so the action functional and equations of motion are invariant under conformal transformations. With this approach the con
Kazuya Koyama, Kayoko Koyama
We show that brane induced gravity can be realized as a low energy effective theory of brane worlds with asymmetric warped compactification. A self-accelerating universe without cosmological constant on the brane can be realized in a model where one side of the bulk has finite volume, but the other side has infinite volume. The spin-2 perturbations for brane
L. Gerland, L. Frankfurt, M. Strikman
We discuss the production of charmonium states in antiproton-nucleus collisions at the $ψ'$ threshold. It is explained that measurements in $\bar p A$ collisions will allow to get new information about the strengths of the inelastic $J/ψN, ψ'N$ interaction, on the production of $Λ_c$ and $\bar{D}$ in charmonium-nucleon interactions and for the first
Jerome P. Gauntlett
We review the substantial progress that has been made in classifying supersymmetric solutions of supergravity theories using G-structures. We also review the construction of supersymmetric black rings that were discovered using the classification of D=5 supergravity solutions.
Peter Jung, Gerhard Wunder
We consider the pulse design problem in multicarrier transmission where the pulse shapes are adapted to the second order statistics of the WSSUS channel. Even though the problem has been addressed by many authors analytical insights are rather limited. First we show that the problem is equivalent to the pure state channel fidelity in quantum information theo
Leonardo Pisani, Roser Valenti
We present first-principles frozen-phonon calculations for the three Raman-active $A_g$ modes in the spin-1/2 layered TiOCl system within two different well-known approaches: the local density approximation (LDA) and the so-called LDA+U approximation. We observe that the inclusion of electron correlation in a mean-field level as implemented in the LDA+U lead
Thomas J. Haines
We study the fibers of Mirkovic-Vilonen convolution morphisms. We prove their equidimensionality when all the coweights in question are minuscule, and some related statements. We give applications to saturation problems for structure constants of Hecke and representation rings. An erratum has been added to correct insufficiencies in the proofs of Lemma 9.4 a
Roderich Tumulka
Both Bohmian mechanics, a version of quantum mechanics with trajectories, and Feynman's path integral formalism have something to do with particle paths in space and time. The question thus arises how the two ideas relate to each other. In short, the answer is, path integrals provide a re-formulation of Schroedinger's equation, which is half of the d
Ulf-G. Meißner, Udit Raha, Akaki Rusetsky
We use the framework of effective field theories to discuss the determination of the S-wave πN scattering lengths from the recent high-precision measurements of pionic deuterium observables. The theoretical analysis proceeds in several steps. Initially, the precise value of the pion-deuteron scattering length a_{πd} is extracted from the data. Next, a_{πd} i
ZEUS Collaboration
A search for lepton-flavor-violating interactions $e p \to μX $ and $e p\to τX $ has been performed with the ZEUS detector using the entire HERA I data sample, corresponding to an integrated luminosity of 130 pb^{-1}. The data were taken at center-of-mass energies, $\sqrt{s}$, of 300 and 318 GeV. No evidence of lepton-flavor violation was found, and constrai
Generalized Radar 4-Coordinates and Equal-Time Cauchy Surfaces for Arbitrary Accelerated Observers
gr-qcDavid Alba, Luca Lusanna
All existing 4-coordinate systems centered on the world-line of an accelerated observer are only locally defined like it happens for Fermi coordinates both in special and general relativity. As a consequence, it is not known how non-inertial observers can build {\it equal-time surfaces} which a) correspond to a conventional observer-dependent definition of s
Cai-Dian Lü, Yue-long Shen, Jin Zhu
The rare decay $B^0 \to ϕϕ$ can occur only via penguin annihilation topology in the standard model. We calculate this channel in the perturbative QCD approach. The predicted branching ratio is very small at ($10^{-8}$). We also give the polarization fractions, which shows that the transverse polarization contribution is comparable to the longitudinal one, du
Z. -F. Li, J. J. Liu, Wolfgang Lucha, W. G. Ma
We study the semirelativistic Hamiltonian operator composed of the relativistic kinetic energy and a static harmonic-oscillator potential in three spatial dimensions and construct, for bound states with vanishing orbital angular momentum, its eigenfunctions in compact form, i. e., as power series, with expansion coefficients determined by an explicitly given
Microscopic Derivation of Causal Diffusion Equation using Projection Operator Method
cond-mat.stat-mechT. Koide
We derive a coarse-grained equation of motion of a number density by applying the projection operator method to a non-relativistic model. The derived equation is an integrodifferential equation and contains the memory effect. The equation is consistent with causality and the sum rule associated with the number conservation in the low momentum limit, in contr
S. M. Gerasyuta, V. I. Kochkin
The relativistic generalization of Faddeev-Yakubovsky approach is constructed in the form of the dispersion relations. The five-quark amplitudes for the low-lying pentaquarks contain u,d,s-quarks. The poles of these amplitudes determine the masses and widths of Theta-pentaquarks.
A. Attili, P. Gallo, M. Rovere
Calculations of the thermodynamical properties of a supercooled liquid confined in a matrix are performed with an inherent structure analysis. The liquid entropy is computed by means of a thermodynamical integration procedure. The contributions to the free energy of the liquid can be decoupled also in confinement in the configurational and the vibrational pa
J Cuevas, JC Eilbeck
We study the symmetric collisions of two mobile breathers/solitons in a model for coupled wave guides with a saturable nonlinearity. The saturability allows the existence of breathers with high power. Three main regimes are observed: breather fusion, breather reflection and breather creation. The last regime seems to be exclusive of systems with a saturable
W. H. T. Vlemmings, H. J. van Langevelde, P. J. Diamond
Through polarization observations, circumstellar masers are excellent probes of the magnetic field in the envelopes of late-type stars. Whereas observations of the polarization of the SiO masers close to the star and on the OH masers much further out were fairly commonplace, observations of the magnetic field strength in the intermediate density and temperat
Kingman Cheung, Cheng-Wei Chiang
In split supersymmetry, the supersymmetric scalar particles are all very heavy, at least at the order of 10^9 GeV, but the gauginos, Higgsinos, and one of the neutral Higgs bosons remain below a TeV. Here we further split the split supersymmetry by taking the Higgsino mass parameter μto be very large. In this case, the μproblem is avoided and we keep the win
Ilia Gogoladze, Tianjun Li, Yukihiro Mimura, S. Nandi
We present an orbifold GUT model in which the NMSSM Higgs trilinear couplings are unified with the three Standard Model gauge couplings. The model is constructed as an N=2 supersymmetric SU(8) gauge theory in six dimensions, which is reduced to the NMSSM with extra U(1) factors upon compactification. Such an unification is in good agreement with experiments.
Michael Martin Nieto, Slava G. Turyshev, John D. Anderson
The Pioneer 10 and 11 spacecraft had exceptional deep-space navigational capabilities. The accuracies of their orbit reconstruction were limited, however, by a small, anomalous, Doppler frequency drift that can be interpreted as an acceleration of (8.74 +/- 1.33) x 10^{-8} cm/s^2 directed toward the Sun. We investigate the possibility that this anomaly could
Hua-Shu Dou
A new universal theory for flow instability and turbulent transition is proposed in this study. Flow instability and turbulence transition have been challenging subjects for fluid dynamics for a century. The critical condition of turbulent transition from theory and experiments differs largely from each other for Poiseuille flows. In this paper, a new mechan
M. A. Novotny, D. T. Robb, S. M. Stinnett, G. Brown
We examine different models and methods for studying finite-temperature magnetic hysteresis in nanoparticles and ultrathin films. This includes micromagnetic results for the hysteresis of a single magnetic nanoparticle which is misaligned with respect to the magnetic field. We present results from both a representation of the particle as a one-dimensional ar
Hua-Shu Dou, Boo Cheong Khoo
The energy gradient method has been proposed with the aim of better understanding the mechanism of flow transition from laminar flow to turbulent flow. In this method, it is demonstrated that the transition to turbulence depends on the relative magnitudes of the transverse gradient of the total mechanical energy which amplifies the disturbance and the energy
Spin Transport Properties in Heisenberg Antiferromagnetic Spin Chains: Spin Current induced by Twisted Boundary Magnetic Fields
cond-mat.str-elWei Zhuo, Xiaoqun Wang, Yupeng Wang
Spin transport properties of the one-dimensional Heisenberg antiferromagnetic spin systems for both $S=1/2$ and S=1 are studied by applying twisted boundary magnetic field. The spin current displays significantly different behavior of the spin transport properties between $S=1/2$ and S=1 cases. For the spin-half case, a London equation for the current and th
HongSheng Zhao, Joseph Silk
We argue that the Milky Way (MW) contains thousands intermediate mass black holes (IMBHs) and minihalos with a fraction of IMBHs still being enshrouded in extremely dense mini-spikes of dark matter (DM) particles. Each containing $10^6\msun$ of dark particles and no baryons in a sphere of 50 pc radius, the minihalos are dense enough to survive the Milky Way
One-dimensional itinerant ferromagnets with Heisenberg symmetry and the ferromagnetic quantum critical point
cond-mat.str-elK. Sengupta, Yong Baek Kim
We study one-dimensional itinerant ferromagnets with Heisenberg symmetry near a ferromagnetic quantum critical point. It is shown that the Berry phase term arises in the effective action of itinerant ferromagnets when the full SU(2) symmetry is present. We explicitly demonstrate that dynamical critical exponent of the theory with the Berry term is $z=2 +{\rm
Unambiguous discrimination of special sets of multipartite states using local measurements and classical communication
quant-phJihane Mimih, Mark Hillery
We initially consider a quantum system consisting of two qubits, which can be in one of two nonorthogonal states, Ψ_0 or Ψ_1. We distribute the qubits to two parties, Alice and Bob. They each measure their qubit and then compare their measurement results to determine which state they were sent. This procedure is error-free, which implies that it must sometim