ECONOMIC CONVERGENCE: EVIDENCE FROM COUNTIES IN THE CAROLINAS

This paper applies a common empirical methodology in testing for convergence of per capita incomes across the counties in North and South Carolina. Decennial census data on per capita income for the 46 counties of South Carolina and the 100 counties of North Carolina are used to test for two types of income convergence over the 1959-2010 time span. The results indicate that both beta and sigma convergence occurred across the counties for the full period, but there were sub-periods (the 1980s, and the 2000s) over which neither measure of convergence was evident. In fact, measured by the beta method, there was statistically significant divergence of per capita incomes across both North and South Carolina counties in the decade of the 1980s. In general, there was great similarity in convergence measured by either method across the counties in these two states

Gaussian Belief with dynamic data and in dynamic network

In this paper we analyse Belief Propagation over a Gaussian model in a dynamic environment. Recently, this has been proposed as a method to average local measurement values by a distributed protocol ("Consensus Propagation", Moallemi & Van Roy, 2006), where the average is available for read-out at every single node. In the case that the underlying network is constant but the values to be averaged fluctuate ("dynamic data"), convergence and accuracy are determined by the spectral properties of an associated Ruelle-Perron-Frobenius operator. For Gaussian models on Erdos-Renyi graphs, numerical computation points to a spectral gap remaining in the large-size limit, implying exceptionally good scalability. In a model where the underlying network also fluctuates ("dynamic network"), averaging is more effective than in the dynamic data case. Altogether, this implies very good performance of these methods in very large systems, and opens a new field of statistical physics of large (and dynamic) information systems.Comment: 5 pages, 7 figure

Polymorphism of CsGaS2 - structural characterization of a new two-dimensional polymorph and study of the phase-transition kinetics

CsGaS2-mC64 was obtained by reaction of CsN3 with stoichiometric amounts of Ga2S3 and S at elevated temperatures. The crystal structure of the air- and moisture stable compound was determined from single-crystal X-ray diffraction data. The colourless solid crystallizes in the monoclinic space group C2/c (no. 15) with the lattice parameters a = 10.5718(6) angstrom, b = 10.5708(6) angstrom, c = 16.0847(8) angstrom, ss = 99.445(4)degrees, V = 1773.1(2) angstrom(3), and Z = 16. The compound crystallizes in the TlGaSe2 structure type and features anionic layers (2)(infinity)[Ga4S84-] consisting of corner-sharing Ga4S10 supertetrahedra. At temperatures above 600 degrees C an irreversible phase-transition to CsGaS2-mC16 occurs. The phase-transition kinetics were studied using in situ high-temperature X-ray powder diffraction techniques. This transition can only be reversed by using high pressures (> 5 GPa at 500 degrees C). The compound was further characterized using Raman- and diffuse reflectance spectroscopy. Chemical bonding was analysed by DFT calculations

FINISHING OR WINNING? THE VARIABLES THAT IMPACTED THE NASCAR CHAMPIONSHIP IN THE CHASE I FORMAT (2004-2013)

Since 2004 NASCAR has evolved its championship format in an effort to put more emphasis on wins, thus encouraging drivers to take more risk to get the race win. Past research has shown that drivers taking a conservative approach, by completing laps rather than going for wins, results in championships. This research attempts to determine if previous models are robust in predicting factors that influence individual points accumulation towards winning the championship and if driver consistency, rather than winning, remains the dominant factor in predicting NASCAR\u27s championship standings

Shear viscosity of the A_1-phase of superfluid 3He

The scattering processes between the quasiparticles in spin- up superfluid with the quasiparticles in spin-down normal fluid are added to the other relevant scattering processes in the Boltzmann collision terms. The Boltzmann equation has been solved exactly for temperatures just below T_c_1. The shear viscosity component of the A_1- phase drops as C_1(1-T/T_c_1)^(1/2). The numerical factor C_1 is in fairly good agreement with the experiments

Universal Behavior of Heavy-Fermion Metals Near a Quantum Critical Point

The behavior of the electronic system of heavy fermion metals is considered. We show that there exist at least two main types of the behavior when the system is nearby a quantum critical point which can be identified as the fermion condensation quantum phase transition (FCQPT). We show that the first type is represented by the behavior of a highly correlated Fermi-liquid, while the second type is depicted by the behavior of a strongly correlated Fermi-liquid. If the system approaches FCQPT from the disordered phase, it can be viewed as a highly correlated Fermi-liquid which at low temperatures exhibits the behavior of Landau Fermi liquid (LFL). At higher temperatures $T$, it demonstrates the non-Fermi liquid (NFL) behavior which can be converted into the LFL behavior by the application of magnetic fields $B$. If the system has undergone FCQPT, it can be considered as a strongly correlated Fermi-liquid which demonstrates the NFL behavior even at low temperatures. It can be turned into LFL by applying magnetic fields $B$. We show that the effective mass $M^*$ diverges at the very point that the N\'eel temperature goes to zero. The $B-T$ phase diagrams of both liquids are studied. We demonstrate that these $B-T$ phase diagrams have a strong impact on the main properties of heavy-fermion metals such as the magnetoresistance, resistivity, specific heat, magnetization, volume thermal expansion, etc.Comment: Revtex, 11 pages, revised and accepted by JETP Let

Behavior of Fermi Systems Approaching Fermion Condensation Quantum Phase Transition from Disordered Phase

The behavior of Fermi systems which approach the fermion condensation quantum phase transition (FCQPT) from the disordered phase is considered. We show that the quasiparticle effective mass $M^*$ diverges as $M^*\propto 1/|x-x_{FC}|$ where $x$ is the system density and $x_{FC}$ is the critical point at which FCQPT occurs. Such a behavior is of general form and takes place in both three dimensional (3D) systems and two dimensional (2D) ones. Since the effective mass $M^*$ is finite, the system exhibits the Landau Fermi liquid behavior. At $|x-x_{FC}|/x_{FC}\ll 1$, the behavior can be viewed as a highly correlated one, because the effective mass is large and strongly depends on the density. In case of electronic systems the Wiedemann-Franz law is held and Kadowaki-Woods ratio is preserved. Beyond the region $|x-x_{FC}|/x_{FC}\ll 1$, the effective mass is approximately constant and the system becomes conventional Landau Fermi liquid.Comment: 9 pages, revtex, no figure

Second wind of the Dulong-Petit Law at a quantum critical point

Renewed interest in 3He physics has been stimulated by experimental observation of non-Fermi-liquid behavior of dense 3He films at low temperatures. Abnormal behavior of the specific heat C(T) of two-dimensional liquid 3He is demonstrated in the occurrence of a T-independent term in C(T). To uncover the origin of this phenomenon, we have considered the group velocity of transverse zero sound propagating in a strongly correlated Fermi liquid. For the first time, it is shown that if two-dimensional liquid 3He is located in the vicinity of the quantum critical point associated with a divergent quasiparticle effective mass, the group velocity depends strongly on temperature and vanishes as T is lowered toward zero. The predicted vigorous dependence of the group velocity can be detected in experimental measurements on liquid 3He films. We have demonstrated that the contribution to the specific heat coming from the boson part of the free energy due to the transverse zero-sound mode follows the Dulong-Petit Law. In the case of two-dimensional liquid 3He, the specific heat becomes independent of temperature at some characteristic temperature of a few mK.Comment: 5 pages, 1 figur