November 2007 arXiv papers — page 7
Showing 601–700 of 5,016 papers
Nelson R. F. Braga, Gustavo Sophia
We discuss the relativistic transformation of the energy of a charged spherical capacitor. The energy stored in the electromagnetic fields observed by an uniformly moving frame is related to that of the rest frame by a factor different from $γ$. Considering the energy and the stresses in the capacitor shells we show that the total energy of the system satisf
Correlations in orbital angular momentum of spatially entangled paired photons generated in parametric downconversion
quant-phClara I. Osorio, Gabriel Molina-Terriza, Juan P. Torres
What are the orbital angular momentum correlations between spatially entangled photon pairs generated in spontaneous parametric down-conversion? We show that the answer to this question can be given in two alternative, although complementary, ways. The answer posed in this letter explains satisfactorily the seemingly contradictory results obtained in differe
Yuval Z. Flicker, Dmitrii Zinoviev
It is shown that the only possible pole of the twisted tensor L-functions in Re(s)\geq 1 is located at s=1 for all quadratic extensions of global fields.
New features of the gluon and ghost propagator in the infrared region from the Gribov-Zwanziger approach
hep-thD. Dudal, S. P. Sorella, N. Vandersickel, H. Verschelde
So far, the infrared behavior of the gluon and ghost propagator based on the Gribov-Zwanziger approach predicted a positivity violating gluon propagator vanishing at zero momentum, and an infrared enhanced ghost propagator. However, recent data based on huge lattices have revealed a positivity violating gluon propagator which turns out to attain a finite non
A. C. Barato, H. Hinrichsen, M. J. de Oliveira
We revisit the scaling properties of a model for non-equilibrium wetting [Phys. Rev. Lett. 79, 2710 (1997)], correcting previous estimates of the critical exponents and providing a complete scaling scheme. Moreover, we investigate a special point in the phase diagram, where the model exhibits a roughening transition related to directed percolation. We argue
L'algèbre des invariants d'un groupe de Coxeter agissant sur un mutiple de sa représentation standard
math.RALoïc Foissy
Let G be a Coxeter group of type A_n, B_n, D_n or I_2(N), or a complex reflection group of type G(de,e,n). Let V be its standard representation and let k be an integer greater than 2. Then G acts on S(V)^{\otimes k}. We show that the algebra of invariants (S(V)^{\otimes k})^G is a free (S(V)^G)^{\otimes k}-module of rank |G|^{k-1}, and that S(V)^{\otimes k}
Consistency and application of moving block bootstrap for non-stationary time series with periodic and almost periodic structure
math.STRafal Synowiecki
The aim of this paper it to establish sufficient conditions for consistency of moving block bootstrap for non-stationary time series with periodic and almost periodic structure. The parameter of the study is the mean value of the expectation function. Consistency holds in quite general situations: if all joint distributions of the series are periodic, then i
Quasi-binary amorphous phase in a 3D system of particles with repulsive-shoulder interactions
cond-mat.softYu. D. Fomin, Daan Frenkel, N. V. Gribova, V. N. Ryzhov
We report a computer-simulation study of the equilibrium phase diagram of a three-dimensional system of particles with a repulsive step potential. Using free-energy calculations, we have determined the equilibrium phase diagram of this system. At low temperatures, we observe a number of distinct crystal phases. However, under certain conditions the system un
James F. Lutsko, Jean Pierre Boon
The Fokker-Planck equation for the probability $f(r,t)$ to find a random walker at position $r$ at time $t$ is derived for the case that the the probability to make jumps depends nonlinearly on $f(r,t)$. The result is a generalized form of the classical Fokker-Planck equation where the effects of drift, due to a violation of detailed balance, and of external
Mathew D. Penrose
Given $n$ independent random marked $d$-vectors (points) $X_i$ distributed with a common density, define the measure $ν_n=\sum_iξ_i$, where $ξ_i$ is a measure (not necessarily a point measure) which stabilizes; this means that $ξ_i$ is determined by the (suitably rescaled) set of points near $X_i$. For bounded test functions $f$ on $R^d$, we give weak and st
Dariusz Chruscinski, Andrzej Kossakowski
We construct a new class of positive indecomposable maps in the algebra of `d x d' complex matrices. These maps are characterized by the `weakest' positivity property and for this reason they are called atomic. This class provides a new reach family of atomic entanglement witnesses which define important tool for investigating quantum entanglement. I
Akio hattori
Multi-fan is an analogous notion of fan. As a fan is associated to a toric variety a multi-fan is associated to a torus orbifold. Orbifold elliptic class and orbifold elliptic genus are defined for a triple of a multi-fan, a set of generating integral vectors of one dimensional cones and a $\mathbb{Q}$ divisor. They are shown to behave functorially with resp
Dariush Latifi
In this paper, we study the set of homogeneous geodesics of a leftinvariant Finsler metric on Lie groups. We first give a simple criterion that characterizes geodesic vectors. As an application, we study some geometric properties of bi-invariant Finsler metrics on Lie groups. In particular a necessary and sufficient condition that left-invariant Randers metr
David Tsiklauri
The generation of parallel electric fields by the propagation of ion cyclotron waves in the plasma with a transverse density inhomogeneity was studied. It was proven that the minimal model required to reproduce the previous kinetic simulation results of E_{||} generation [Tsiklauri et al 2005, Genot et al 2004] is the two-fluid, cold plasma approximation in
I. A. Campbell, A. Fert, A. R. Pomeroy
Measurements of resistivities of dilute iron based alloys show strong deviations from Matthiessen's rule. These deviations can be explained by a model in which spin up and spin down electrons conduct in parallel. The results are consistent with the theory of impurity shielding in these alloys. [This 1967 paper provides the first experimental demonstratio
Christopher Eltschka, Andreas Osterloh, Jens Siewert, Armin Uhlmann
We give a complete solution for the three-tangle of mixed three-qubit states composed of a generalized GHZ state, a|000>+b|111>, and a generalized W state, c|001>+d|010>+f|100>. Using the methods introduced by Lohmayer et al. we provide explicit expressions for the mixed-state three-tangle and the corresponding optimal decompositions for this more general ca
M. J. Morelli, S. Tanase-Nicola, R. J. Allen, P. R. ten Wolde
We present a detailed analysis, based on the Forward Flux Sampling (FFS) simulation method, of the switching dynamics and stability of two models of genetic toggle switches, consisting of two mutually-repressing genes encoding transcription factors (TFs); in one model (the exclusive switch), they mutually exclude each other's binding, while in the other
S. Calchi Novati
In the framework of the search of dark matter in galactic halos in form of massive compact halo object (MACHOs), we discuss the status of microlensing observations towards the Magellanic Clouds and the Andromeda galaxy, M31. The detection of a few microlensing events has been reported, but an unambiguous conclusion on the halo content in form on MACHOs has n
Ramin Golestanian, Armand Ajdari
A conformation space kinetic model is constructed to drive the deformation cycle of a three-sphere swimmer to achieve propulsion at low Reynolds number. We analyze the effect of an external load on the performance of this kinetic swimmer, and show that it depends sensitively on where the force is exerted, so that there is no general force--velocity relation.
J. Vijande, A. Valcarce, P. Gonzalez, H. Garcilazo
We present a study of the baryon spectra for all flavor sectors within a constituent quark model. We address some of the outstanding problems in baryon spectroscopy, as for example the spin splitting evolution for te different flavor sectors, the flavor independence of confinement and the missing state problem.
G. Catanzaro
In this paper we report on the real nature of the star HD 145792, classified as He weak in {\it ``The General Catalogue of Ap and Am stars''}. By means of FEROS@ESO1.52m high resolution spectroscopic data, we refined the atmospheric parameters of the star, obtaining: T$_{\rm eff}$ = 14400 $\pm$ 400 K, $\log g$ = 4.06 $\pm$ 0.08 and $ξ$ = 0 $^{+0.6}$
Hua-Hui Xiong, Taotao Qiu, Yi-Fu Cai, Xinmin Zhang
In this paper, we study the possibility of model building of cyclic universe with Quintom matter in the framework of Loop Quantum Cosmology. After a general demonstration, we provide two examples, one with double-fluid and another double-scalar field, to show how such a scenario is obtained. Analytical and numerical calculations are both presented in the pap
L. Coccato, R. Swaters, V. C. Rubin, S. D'Odorico
We studied the bulge and the disk kinematic of the giant Low Surface Brightness (LSB) galaxy ESO 323-G064 in order to investigate its dynamics and its Dark Matter (DM) content. We observed the galaxy with the integral field spectroscopy (VLT/VIMOS, in IFU configuration). Results for the gaseous kinematics (bulge and disk) and stellar kinematics (bulge) are p
C. A. L. Bailer-Jones
I outline a method for estimating astrophysical parameters (APs) from multidimensional data. It is a supervised method based on matching observed data (e.g. a spectrum) to a grid of pre-labelled templates. However, unlike standard machine learning methods such as ANNs, SVMs or k-nn, this algorithm explicitly uses domain information to better weight each data
C. A. L. Bailer-Jones
Models of brown dwarf atmospheres suggest they exhibit complex physical behaviour. Observations have shown that they are indeed dynamic, displaying small photometric variations over timescales of hours. Here I report results of infrared (0.95-1.64 micron) spectrophotometric monitoring of four field L and T dwarfs spanning timescales of 0.1-5.5 hrs, the goal
W. Trautmann, P. Adrich, T. Aumann, C. O. Bacri
The N/Z dependence of projectile fragmentation at relativistic energies has been studied in a recent experiment at the GSI laboratory with the ALADiN forward spectrometer coupled to the LAND neutron detector. Besides a primary beam of 124Sn, also secondary beams of 124La and 107Sn delivered by the FRS fragment separator have been used in order to extend the
L. N. Abesalashvili, L. T. Akhobadze
The obtained $π^{-}$ and charged multiplicity distribution parameters of Gluon Dominance Model explain the experimental data in nucleus-nucleus, p nucleus, pd, pp, p antip and $π^{-}$(p,n) interactions. We have undertaken an attempt to give description in different processes of multiparticle production by means of a unifed approach based on quark-gluon pictu
Takayuki Watanabe, Toru Suzuki, Peter Schuck
We study static properties of attractively interacting Bose-Fermi mixtures of uniform atomic gases at zero temperature. Using Green's function formalism we calculate boson-fermion scattering amplitude and fermion self-energy in the medium to lowest order of the hole line expansion. We study ground state energy and pressure as functions of the scattering
Bounds for the covariance of functions of infinite variance stable random variables with applications to central limit theorems and wavelet-based estimation
math.STVladas Pipiras, Murad S. Taqqu, Patrice Abry
We establish bounds for the covariance of a large class of functions of infinite variance stable random variables, including unbounded functions such as the power function and the logarithm. These bounds involve measures of dependence between the stable variables, some of which are new. The bounds are also used to deduce the central limit theorem for unbound
Fernado Sancho, Pedro Sancho
We give a direct and elementary proof of the theorem on formal functions by studying the behaviour of the Godement resolution of a sheaf of modules under completion.
L. Mashonkina, G. Zhao, T. Gehren, W. Aoki
Stellar parameters and abundances of Na, Mg, Al, K, Ca, Sr, Ba, and Eu are determined for four very metal-poor stars (-2.66 < [Fe/H] < -2.15) based on non-LTE line formation and analysis of high-resolution (R ~60000 and 90000) high signal-to-noise (S/N > 200) observed spectra. A model atom for H I is presented. An effective temperature was obtained from the
Robert Waelder
We define the singular elliptic genus for arbitrary normal surfaces, prove that it is a birational invariant, and show that it generalizes the singular elliptic genus of Borisov and Libgober and the stringy $χ_y$ genus of Batyrev and Veys.
Hirotaka Niitsuma, Takashi Okada
Covariances from categorical variables are defined using a regular simplex expression for categories. The method follows the variance definition by Gini, and it gives the covariance as a solution of simultaneous equations. The calculated results give reasonable values for test data. A method of principal component analysis (RS-PCA) is also proposed using reg
I. Ribas, J. Morales, C. Jordi, I. Baraffe
Numerous investigations on the fundamental properties of low-mass stars using eclipsing binaries indicate a strong discrepancy between theory and observations that is still awaiting explanation. Current models seem to predict radii for stars less massive than the Sun that are some 10% smaller than observed, while their effective temperatures are some 5% larg
Gian F. Giudice, Hyung Do Kim, Riccardo Rattazzi
We propose a natural solution to the mu problem in gauge mediation. It relies on the logarithmic dependence of the effective Kahler potential on the messenger threshold superfield X. Thus, mu and Bmu naturally arise at one and two loops, respectively. Moreover B has the same phase as the gaugino mass and the supersymmetric CP problem is solved as well.
Yuval Z. Flicker, Dmitrii Zinoviev
We provide a purely local computation of the (elliptic) twisted (by "transpose-inverse") character of the representation π=I(\1) of PGL(3) over a p-adic field induced from the trivial representation of the maximal parabolic subgroup. This computation is independent of the theory of the symmetric square lifting of [IV] of automorphic and admissible re
A. Matulis, F. M. Peeters
Dirac fermions interacting with a cylindrically symmetric quantum dot potential created in single and bilayer graphene are not confined but form quasi-bound states. The broadening of these quasi-bound states (i. e. the inverse of their lifetimes) decreases (increases) with the orbital momentum of the electron in the case of graphene (bilayer). Quasi-bound st
Víctor Rivero
We prove that a positive self-similar Markov process $(X,\mathbb{P})$ that hits 0 in a finite time admits a self-similar recurrent extension that leaves 0 continuously if and only if the underlying Lévy process satisfies Cramér's condition.
Bernard Collet, Michel Destrade, Gérard A. Maugin
Functionally Graded Materials are inhomogeneous elastic bodies whose properties vary continuously with space. Hence consider a half-space (x_2>0) occupied by a special Functionally Graded Material made of an hexagonal (6 mm) piezoelectric crystal for which the elastic stiffness c44, the piezoelectric constant e15, the dielectric constant epsilon11, and the m
Alessandro Perotti
Let H be the space of quaternions, with its standard hypercomplex structure. Let R(D) be the module of regular functions on D. For every unitary vector p in S^2, R(D) contains the space of holomorphic functions w.r.t. the complex structure J_p induced by p. We prove the existence, on any bounded domain D, of regular functions that are not J_p-holomorphic for
Bernard Collet, Michel Destrade
Consider a layer made of a m3m insulator crystal, with faces cut parallel to a symmetry plane. Then bond it onto a semi-infinite mm2 piezoelectric substrate. For a X- or Y -cut of the substrate, a Love wave can propagate in the resulting structure and the corresponding dispersion equation is derived analytically. It turns out that a fully explicit treatment
Acoustic waves at the interface of a pre-stressed incompressible elastic solid and a viscous fluid
physics.flu-dynMélanie Otténio, Michel Destrade, Raymond W. Ogden
We analyse the influence of pre-stress on the propagation of interfacial waves along the boundary of an incompressible hyperelastic half-space that is in contact with a viscous fluid extending to infinity in the adjoining half-space. One aim is to derive rigorously the incremental boundary conditions at the interface; this derivation is delicate because of t
Michel Destrade, Giuseppe Gaeta, Giuseppe Saccomandi
Weierstrass's theory is a standard qualitative tool for single degree of freedom equations, used in classical mechanics and in many textbooks. In this Brief Report we show how a simple generalization of this tool makes it possible to identify some differential equations for which compact and even semicompact traveling solitary waves exist. In the framewo
Patrick Corn
Following (and elaborating on) a method of Logan and van Luijk, we exhibit explicit genus-2 curves whose Jacobians have nontrivial 2-torsion in their Tate-Shafarevich groups.
L. He, J. -N. Zhang, Yunbo Zhang, S. Yi
We investigate the stability and the free expansion of a trapped dipolar Fermi gas. We show that stabilizing the system relying on tuning the trap geometry is generally inefficient. We further show that the expanded density profile always gets stretched along the attractive direction of dipolar interaction. We also point out that by switching off the dipolar
Alexey A. Kovalev, Liviu P. Zârbo, Y. Tserkovnyak, G. E. W. Bauer
Torsional oscillations of a free-standing semiconductor beam are shown to cause spin-dependent oscillating potentials that spin-polarize an applied charge current in the presence of intentional or disorder scattering potentials. We propose several realizations of mechanical spin generators and manipulators based on this piezo-spintronic effect.
How do diquark fluctuations and chiral soft modes affect di-lepton production in the deconfined phase?
hep-phTeiji Kunihiro, Masakiyo Kitazawa, Yukio Nemoto
We examine diquark fluctuations and chiral soft modes existing in the precritical region of color superconductivity and chiral transition, respectively, at finite temperature and density. We evaluate how they contribute to anomalous di-lepton production; although there appear peaks in the spectral function owing to the existence of the soft modes, the enhanc
Relativistic corrections to transition frequencies of Fe I and search for variation of the fine structure constant
physics.atom-phV. A. Dzuba, V. V. Flambaum
Relativistic energy shifts of the low energy levels of Fe have been calculated using the Dirac-Hartree-Fock and configuration interaction techniques. The results are to be used in the search for the space-time variation of the fine structure constant in quasar absorption spectra. The values of the shifts are the largest among those used in the analysis so fa
Le Anh Vinh
We study a Szemerédi-Trotter type theorem in finite fields. We then use this theorem to obtain an improved sum-product estimate in finite fields.
Positive and negative effective mass of classical particles in oscillatory and static fields
physics.plasm-phI. Y. Dodin, N. J. Fisch
A classical particle oscillating in an arbitrary high-frequency or static field effectively exhibits a modified rest mass m_eff derived from the particle averaged Lagrangian. Relativistic ponderomotive and diamagnetic forces, as well as magnetic drifts, are obtained from the m_eff dependence on the guiding center location and velocity. The effective mass is
M. Vijayajayanthi, T. Kanna, M. Lakshmanan
Mixed type (bright-dark) soliton solutions of the integrable N-coupled nonlinear Schr{ö}dinger (CNLS) equations with mixed signs of focusing and defocusing type nonlinearity coefficients are obtained by using Hirota's bilinearization method. Generally, for the mixed N-CNLS equations the bright and dark solitons can be split up in $(N-1)$ ways. By analysi
Yi-Fu Cai, Yi Wang
The quantum behavior of noncommutative eternal inflation is quite different from the usual knowledge. Unlike the usual eternal inflation, the quantum fluctuation of noncommutative eternal inflation is suppressed by the Hubble parameter. Due to this, we need to reconsider many conceptions of eternal inflation. In this paper we study the Hawking-Moss tunneling
Clifford Cheung, A. Liam Fitzpatrick, Lisa Randall
We propose a model of spontaneous CP violation to address the strong CP problem in warped extra dimensions that relies on sequestering flavor and CP violation. We assume that brane-localized Higgs Yukawa interactions respect a U(3) flavor symmetry that is broken only by bulk fermion mass and Yukawa terms. All CP violation arises from the vev of a CP-odd scal
Duncan Galloway
X-ray timing of neutron stars in low-mass X-ray binaries (LMXBs) with RXTE has since 1996 revealed several distinct high-frequency phenomena. Among these are oscillations during thermonuclear (type-I) bursts, which (in addition to persistent X-ray pulsations) are thought to trace the neutron star spin. Recent discoveries bring the total number of measured LM
Silke Weinfurtner
We discuss the possibility that spacetime geometry may be an emergent phenomenon. This idea has been motivated by the Analogue Gravity programme. These are systems where the kinematics of small perturbations are dominated by an effective gravitational field. In these models there is no obvious connection between the "gravitational" field tensor and t
Rui Zhang, Ying Chang Liang
In cognitive radio (CR) networks, there are scenarios where the secondary (lower priority) users intend to communicate with each other by opportunistically utilizing the transmit spectrum originally allocated to the existing primary (higher priority) users. For such a scenario, a secondary user usually has to trade off between two conflicting goals at the sa
K. Slifer
Solid NH3 and ND3 provide a highly polarizable, radiation resistant source of polarized protons and deuterons and have been used extensively in high luminosity experiments investigating the spin structure of the nucleon. Over the past twenty years, the UVA polarized target group has been instrumental in producing and polarizing much of the material used in t
K. Slifer
Select recent results from the Thomas Jefferson National Laboratory Spin Physics program, along with the perspective on some upcoming experiments.
Three-Dimensional Simulations of Kelvin-Helmholtz Instability in Settled Dust Layers in Protoplanetary Disks
astro-phJoseph A. Barranco
As dust settles in a protoplanetary disk, a vertical shear develops because the dust-rich gas in the midplane orbits at a rate closer to true Keplerian than the slower-moving dust-depleted gas above and below. A classical analysis (neglecting the Coriolis force and differential rotation) predicts that Kelvin-Helmholtz instability occurs when the Richardson n
Ding-Xiong Wang, Yong-Chun Ye, Yang Li, Zhao-Jiang Ge
Three energy mechanisms invoking large-scale magnetic fields are incorporated in a model to interpret jet production in black hole (BH) systems, i.e., the Blandford-Znajek (BZ), the magnetic coupling (MC) and Blandford-Payne (BP) processes. These energy mechanisms can coexist in BH accretion disc based on the magnetic field configurations constrained by the
Parastoo Sadeghi, Pascal O. Vontobel, Ramtin Shams
We consider the problem of minimizing upper bounds and maximizing lower bounds on information rates of stationary and ergodic discrete-time channels with memory. The channels we consider can have a finite number of states, such as partial response channels, or they can have an infinite state-space, such as time-varying fading channels. We optimize recently-p
Absolutely Continuous Spectrum of a Polyharmonic Operator with a Limit Periodic Potential in Dimension Two
math-phYulia Karpeshina, Young-Ran Lee
We consider a polyharmonic operator $H=(-Δ)^l+V(x)$ in dimension two with $l\geq 6$, $l$ being an integer, and a limit-periodic potential $V(x)$. We prove that the spectrum contains a semiaxis of absolutely continuous spectrum.
Viscoelasticity and primitive path analysis of entangled polymer liquids: From f-actin to polyethylene
cond-mat.softNariya Uchida, Gary S. Grest, Ralf Everaers
We combine computer simulations and scaling arguments to develop a unified view of polymer entanglement based on the primitive path analysis (PPA) of the microscopic topological state. Our results agree with experimentally measured plateau moduli for three different polymer classes over a wide rangeof reduced polymer densities: (i) semi-dilute theta solution
S. N. Longmore, M. G. Burton, C. R. Purcell, P. Barnes
We have recently completed an observing program with the Australia Telescope Compact Array towards massive star formation regions traced by 6.7 GHz methanol maser emission. We found the molecular cores could be separated into groups based on their association with/without methanol maser and 24 GHz continuum emission. Analysis of the molecular and ionised gas
Eiko Kin
Li-York theorem tells us that a period 3 orbit for a continuous map of the interval into itself implies the existence of a periodic orbit of every period. This paper concerns an analogue of the theorem for homeomorphisms of the 2-dimensional disk. In this case a periodic orbit is specified by a braid type and on the set of all braid types Boyland's dynam
Igor V. Igumenshchev
The dynamics and structure of accretion disks, which accumulate the vertical magnetic field in the centers, are investigated using two- and three-dimensional MHD simulations. The central field can be built up to the equipartition level and disrupts a nearly axisymmetric outer accretion disk inside a magnetospheric radius, forming a magnetically arrested disk
The delta method for analytic functions of random operators with application to functional data
math.STJ. Cupidon, D. S. Gilliam, R. Eubank, F. Ruymgaart
In this paper, the asymptotic distributions of estimators for the regularized functional canonical correlation and variates of the population are derived. The method is based on the possibility of expressing these regularized quantities as the maximum eigenvalue and the corresponding eigenfunctions of an associated pair of regularized operators, similar to t
Retired A Stars and Their Companions II: Jovian planets orbiting kappa Coronae Borealis and HD167042
astro-phJohn A. Johnson, Geoffrey W. Marcy, Debra A. Fischer, Jason T. Wright
We report precise Doppler measurements of two evolved stars, kappa CrB (HD142091) and HD 167042, obtained at Lick Observatory as part of our search for planets orbiting intermediate-mass subgiants. Periodic variations in the radial velocities of both stars reveal the presence of substellar orbital companions. These two stars are notably massive with stellar
Vertical Shearing Instabilities in Radially Shearing Disks: The Dustiest Layers of the Protoplanetary Nebula
astro-phE. Chiang
Gravitational instability of a vertically thin, dusty sheet near the midplane of a protoplanetary disk has long been proposed as a way of forming planetesimals. Before Roche densities can be achieved, however, the dust-rich layer, sandwiched from above and below by more slowly rotating dust-poor gas, threatens to overturn and mix by the Kelvin-Helmholtz inst
Finite temperature phase diagram of a spin-polarized ultracold Fermi gas in a highly elongated harmonic trap
cond-mat.stat-mechXia-Ji Liu, Hui Hu, Peter D. Drummond
We investigate the finite temperature properties of an ultracold atomic Fermi gas with spin population imbalance in a highly elongated harmonic trap. Previous studies at zero temperature showed that the gas stays in an exotic spatially inhomogeneous Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) superfluid state at the trap center; while moving to the edge, the sys
Flow-correlated dilution of a regular network leads to a percolating network during tumor induced angiogenesis
q-bio.CBRaja Paul
We study a simplified stochastic model for the vascularization of a growing tumor, incorporating the formation of new blood vessels at the tumor periphery as well as their regression in the tumor center. The resulting morphology of the tumor vasculature differs drastically from the original one. We demonstrate that the probabilistic vessel collapse has to be
T. Duguet, T. Lesinski
The present contribution reports the first systematic finite-nucleus calculations performed using the Energy Density Functional method and a non-empirical pairing functional derived from low-momentum interactions. As a first step, the effects of Coulomb and the three-body force are omitted while only the bare two-nucleon interaction at lowest order is consid
V. E. Nazaikinskii, A. Yu. Savin, B. Yu. Sternin
We define Atiyah-Bott index on stratified manifolds and express it in topological terms. By way of example, we compute this index for geometric operators on manifolds with edges.
Creation of the X-ray Cavity Jet and its Radio Lobe in M87/Virgo with Cosmic Rays; Relevance to Relic Radio Sources
astro-phWilliam G. Mathews, Fabrizio Brighenti
Young cavities in the X-ray emitting hot gas in galaxy clusters are often filled with radio synchrotron emission and it is widely thought that the cavities are inflated by these cosmic rays. At a later stage of its evolution, when the cavity becomes buoyant, the converging flow of gas beneath the cavity results in a filament of thermal gas, a cavity jet, tha
Elastic constants and volume changes associated with two high-pressure rhombohedral phase transformations in vanadium
cond-mat.mtrl-sciB. Lee, R. E. Rudd, J. E. Klepeis, R. Becker
We present results from ab initio calculations of the mechanical properties of the rhombohedral phase (beta) of vanadium metal reported in recent experiments, and other predicted high-pressure phases (gamma and bcc), focusing on properties relevant to dynamic experiments. We find that the volume change associated with these transitions is small: no more than
Level-dynamic approach to the excited spectra of the Jahn-Teller model - kink-train lattice and 'glassy' quantum phase
cond-mat.softE. Majernikova, S. Shpyrko
The dynamics of excited phonon spectra of the Exe Jahn-Teller (hereafter, JT) model mapped onto the generalized Calogero-Moser (gCM) gas of pseudoparticles implies a complex interplay between nonlinearity and fluctuations of quasiparticle trajectories. A broad crossover appears in a pseudotime (interaction strength) between the initial oscillator region and
Thomas F. Jordan, Anil Shaji, E. C. G. Sudarshan
A Markov approximation in open quantum dynamics can give unphysical results when a map acts on a state that is not in its domain. This is examined here in a simple example, an open quantum dynamics for one qubit in a system of two interacting qubits, for which the map domains have been described quite completely. A time interval is split into two parts and t
Phuoc Ha
We construct a general parametrization of the baryon octet and decuplet mass operators including the three-body terms using the unit operator and the symmetry-breaking factors $M^d=\textrm{diag} (0,1,0)$ and $M^s=\textrm{diag} (0,0,1)$ in conjunction with the spin operators. Our parametrization has the minimal number of operators needed to describe all the o
Teppo Mattsson
Motivated by the observed cosmic matter distribution, we present the following conjecture: due to the formation of voids and opaque structures, the average matter density on the path of the light from the well-observed objects changes from Omega_M ~ 1 in the homogeneous early universe to Omega_M ~ 0 in the clumpy late universe, so that the average expansion
Ruochuan Liu
Given a p-adic representation of the Galois group of a local field, we show that its Galois cohomology can be computed using the associated etale (phi,Gamma)-module over the Robba ring; this is a variant of a result of Herr. We then establish analogues, for not necessarily etale (phi,Gamma)-modules over the Robba ring, of the Euler-Poincare characteristic fo
Thermodynamics and Relativity: A Message to Physics Teachers (for an easier understanding of the thermodynamic theory)
physics.gen-phJean-Louis Tane
Whoever has to learn or to teach thermodynamics is confronted with conceptual difficulties which are specific to this field of physics ([1],[2]). It seems that they can be eliminated by inserting relativity in the thermodynamic theory. The aim of this paper is to summarize the problem and draw attention upon a fundamental point of the discussion.
Italo J. Dejter
We show there is an uncountable number of parallel total perfect codes in the integer lattice graph $Λ$ of $\R^2$. In contrast, there is just one 1-perfect code in $Λ$ and one total perfect code in $Λ$ restricting to total perfect codes of rectangular grid graphs (yielding an asymmetric, Penrose, tiling of the plane). We characterize all cycle products $C_m\
N. E. Grayson, A. Taormina, R. Twarock
A construction method for duplex cage structures with icosahedral sym- metry made out of single-stranded DNA molecules is presented and applied to an icosidodecahedral cage. It is shown via a mixture of analytic and computer techniques that there exist realisations of this graph in terms of two circular DNA molecules. These blueprints for the organisation of
Hongki Min, A. H. MacDonald
We show that the low-energy electronic structure of arbitrarily stacked graphene multilayers with nearest-neighbor interlayer tunneling consists of chiral pseudospin doublets. Although the number of doublets in an $N$-layer system depends on the stacking sequence, the pseudospin chirality sum is always $N$. $N$-layer stacks have $N$ distinct Landau levels at
Yong-Geun Oh, Ke Zhu
We define an enhanced compactification of Floer trajectories under Morse background using the adiabatic degeneration and the scale-dependent gluing techniques. The compactification reflects the 1-jet datum of the smooth Floer trajectories nearby the limiting nodal Floer trajectories arising from adiabatic degeneration of the background Morse function. This p
Low-energy subgap states and the magnetic flux periodicity in d-wave superconducting rings
cond-mat.supr-conYu. S. Barash
Wave functions of low-energy quasiparticle subgap states in d-wave superconducting rings, threaded by Aharonov-Bohm magnetic flux, are found analytically. The respective energies are closest to the midgap position at small magnetic fluxes and deviate from the Fermi surface due to the Doppler shift, produced by the supercurrent. The Doppler-shifted zero-energ
Ilya Kapovich, Martin Lustig
Let $F_N$ be a free group of rank $N\ge 2$, let $μ$ be a geodesic current on $F_N$ and let $T$ be an $\mathbb R$-tree with a very small isometric action of $F_N$. We prove that the geometric intersection number $<T, μ>$ is equal to zero if and only if the support of $μ$ is contained in the dual algebraic lamination $L^2(T)$ of $T$. Applying this result, we o
P. Badziag, C. Brukner, W. Laskowski, T. Paterek
We present an intuitive geometrical entanglement criterion. It allows formulation of simple and experimentally friendly sufficient conditions for entanglement. The conditions are illustrated with several examples. Moreover, a generalization of our approach is a necessary and sufficient separability condition. It can be associated with a family of entanglemen
R. Balasubramanian, Gyan Prakash, D. S. Ramana
A finite abelian group $G$ of cardinality $n$ is said to be of type III if every prime divisor of $n$ is congruent to 1 modulo 3. We obtain a classification theorem for sum-free subsets of largest possible cardinality in a finite abelian group $G$ of type III. This theorem, when taken together with known results, gives a complete characterisation of sum-free
Michal Spalinski
Dirac-Born-Infeld scalar field theories which appear in the context of inflation in string theory in general have a field dependent speed of sound. It is however possible to write down DBI models which possess exact solutions characterized by a constant speed of sound different from unity. This requires that the potential and the effective D-brane tension ap
Geoff Goehle
This paper introduces a generalization of Pontryagin duality for locally compact Hausdorff abelian groups to locally compact Hausdorff abelian group bundles.
Rabi oscillations and excitation trapping in the coherent excitation of a mesoscopic frozen Rydberg gas
physics.atom-phMarkus Reetz-Lamour, Thomas Amthor, Johannes Deiglmayr, Matthias Weidemüller
We demonstrate the coherent excitation of a mesoscopic ensemble of about 100 ultracold atoms to Rydberg states by driving Rabi oscillations from the atomic ground state. We employ a dedicated beam shaping and optical pumping scheme to compensate for the small transition matrix element. We study the excitation in a weakly interacting regime and in the regime
S. G. Rajeev
We show that classical thermodynamics has a formulation in terms of Hamilton-Jacobi theory, analogous to mechanics. Even though the thermodynamic variables come in conjugate pairs such as pressure/volume or temperature/entropy, the phase space is odd-dimensional. For a system with n thermodynamic degrees of freedom it is (2n+1)-dimensional. The equations of
Dibyendu Roy, Abhishek Dhar
We consider heat conduction across an ordered oscillator chain with harmonic interparticle interactions and also onsite harmonic potentials. The onsite spring constant is the same for all sites excepting the boundary sites. The chain is connected to Ohmic heat reservoirs at different temperatures. We use an approach following from a direct solution of the La
Eric Errthum
The $j$-function acts as a parametrization of the classical modular curve. Its values at complex multiplication (CM) points are called singular moduli and are algebraic integers. A Shimura curve is a generalization of the modular curve and, if the Shimura curve has genus 0, a rational parameterizing function exists and when evaluated at a CM point is again a
Daniel Boer, Andre Utermann, Erik Wessels
We present a new phenomenological model of the dipole scattering amplitude to demonstrate that the RHIC data for hadron production in d-Au collisions for all available rapidities are compatible with geometric scaling, just like the small-x inclusive DIS data. A detailed comparison with earlier geometric scaling violating models of the dipole scattering ampli
Matthew Daws, Volker Runde
It is known that ${\cal B}(\ell^p)$ is not amenable for $p =1,2,\infty$, but whether or not ${\cal B}(\ell^p)$ is amenable for $p \in (1,\infty) \setminus \{2 \}$ is an open problem. We show that, if ${\cal B}(\ell^p)$ is amenable for $p \in (1,\infty)$, then so are $\ell^\infty({\cal B}(\ell^p))$ and $\ell^\infty({\cal K}(\ell^p))$. Moreover, if $\ell^\inft
R. Danneau, F. Wu, M. F. Craciun, S. Russo
We have investigated shot noise in graphene field effect devices in the temperature range of 4.2--30 K at low frequency ($f$ = 600--850 MHz). We find that for our graphene samples with large width over length ratio $W/L$, the Fano factor $\mathfrak{F}$ reaches a maximum $\mathfrak{F} \sim$ 1/3 at the Dirac point and that it decreases strongly with increasing
A. V. Lebedev, G. B. Lesovik, G. Blatter
We present a non-perturbative expression for the scattering matrix of $N$ particles interacting inside a quantum dot. Characterizing the dot by its resonances, we find a compact form for the scattering matrix in a real-time representation. We study the transmission probabilities and interaction-induced orbital entanglement of two electrons incident on the do
Karen L. Masters, Christopher M. Springob, John P. Huchra
The 2 Micron All-Sky Survey (2MASS) Tully-Fisher Survey (2MTF) aims to measure Tully-Fisher (TF) distances to all bright inclined spirals in the 2MASS Redshift Survey (2MRS). Essential to this project is a universal calibration of the TF relation in the 2MASS J (1.2 um), H (1.6 um) and K (2.2 um) bands. We present the first bias corrected or universal TF tem