Stronger two-observer all-versus-nothing violation of local realism

We introduce a two-observer all-versus-nothing proof of Bell's theorem which reduces the number of required quantum predictions from 9 [A. Cabello, Phys. Rev. Lett. 87, 010403 (2001); Z.-B. Chen et al., Phys. Rev. Lett. 90, 160408 (2003)] to 4, provides a greater amount of evidence against local realism, reduces the detection efficiency requirements for a conclusive experimental test of Bell's theorem, and leads to a Bell's inequality which resembles Mermin's inequality for three observers [N. D. Mermin, Phys. Rev. Lett. 65, 1838 (1990)] but requires only two observers.Comment: REVTeX4, 5 page

On the non-equivalence of Lorenz System and Chen System

In this paper, we prove that the Chen system with a set of chaotic parameters is not smoothly equivalent to the Lorenz system with any parameters

New laboratory lifetime measurements of U II for the uranium cosmochronometer

We present new measurements of radiative lifetimes for six energy levelsof singly ionized uranium, U II, using laser-induced fluorescencetechnique. One of the levels,5f36d7p6M13/2 at 26191 cm-1,decays by a transition at 3859.6 Å. This line has recently beenobserved in the spectrum of the metal-poor star CS1082-001, the firstdetection of uranium outside the solar system. The lambda 3859 line canbe used as the presently most accurate cosmochronometer (Cayrel et al.cite{Cayrel}). Our value of the lifetime of the6M13/2 level is 18.6+/-0.7 ns, and it confirms thef-value used in the Nature article by Cayrel et al. (cite{Cayrel}),which is based on an experimental lifetime of 20+/-5 ns (Chen &Borzileri cite{Chen}). The new measurement also removes the doubt aboutthe choice between that value and other f-values in the literature,differing by a factor of 3. Adopting the same branching fraction as Chen& Borzileri (cite{Chen}) for the 3859.6 Å line, we derive agf-value of 0.68, which is 8% higher than the value used by Cayrel etal. (cite{Cayrel}). Of significance for the chronometer is also thereduced uncertainty of the radiative lifetime, 4% compared to 25%, andconsequently of the f-value, which should decrease the uncertainty inthe determination of the stellar age considerably

The proton spin decomposition : path dependence and gauge symmetry

We discuss the different types of decomposition of the proton spin. We stress that, despite their lack of uniqueness, the Chen et al. and Wakamatsu decompositions are perfectly measurable. We argue that a large part of the recent controversies boils down to the fact that there actually exist two types of gauge transformations in the Chen et al. approach, where physical and gauge degrees of freedom of the gauge potential are explicitly separated. By carefully distinguishing these two types of gauge transformations, one can easily understand how the concepts of gauge invariance, Stueckelberg symmetry, path dependence and measurability are linked to each other.Comment: 9 pages, contribution to the proceedings of the QCD Evolution 2013, May 6-10, JLab, Newport News, US

Stability of the solitary wave solutions to a coupled BBM system

In this work, we present a stability criteria for the solitary wave solutions to a BBM system that contains coupled nonlinear terms. Using the idea by Bona, Chen and Karakashian and exploiting the accurate point spectrum information of the associated Schrodinger operator, we improve the stability results previously got by Pereira.Comment: 15 page

Comment on "The Spirit of Capitalism and Stock Market Prices" By G.S. Bakshi and Z. Chen (AER, 1996)

share prices;capitalism;financial markets