Quantification of entanglement via uncertainties

We show that entanglement of pure multi-party states can be quantified by means of quantum uncertainties of certain basic observables through the use of measure that has been initially proposed in [10] for bipartite systems.Comment: Changed content, references added 7 pages, no figures, PRA in pres

Steady state entanglement of two atoms created by classical driving field

The stabilization of steady state entanglement caused by action of a classical driving field in the system of two-level atoms with the dipole interaction accompanied by spontaneous emission is discussed. An exact solution shows that the maximum amount of concurrence that can be achieved in Lamb-Dicke limit is 0.43, which corresponds to the entanglement $\mathcal{E}_{max}=0.285$ ebit. Dependence of entanglement on interatomic distance and classical driving field is examined numerically.Comment: 14 pages, 2 figure

A simple test for hidden variables in spin-1 system

We resolve an old problem about the existence of hidden parameters in a three-dimensional quantum system by constructing an appropriate Bell's type inequality. This reveals a nonclassical nature of most spin-$1$ states. We shortly discuss some physical implications and an underlying cause of this nonclassical behavior, as well as a perspective of its experimental verification.Comment: 4 pages, 1 figur

Correlations between the ranks of submatrices and weights of random codes

AbstractThe results of our study are twofold. From the random matrix theory point of view we obtain results on the rank distribution of column submatrices. We give the moments and the covariances between the ranks (q−rank) of such submatrices. We conjecture the counterparts of these results for arbitrary submatrices. The case of higher correlations gets drastically complicated even in the case of three submatrices. We give a formula for the correlation of ranks of three submatrices and a conjecture for its closed form. From the code theoretical point of view our study yields the covariances of the coefficients of the weight enumerator of a random code. Particularly interesting is that the coefficients of the weight enumerator of a code with random parity check matrix are uncorrelated. We give a conjecture for the triple correlations between the coefficients of the weight enumerator of a random code

Peculiarities of Soil Structure Interaction in Construction with Artificial Bases

A technique is suggested to increase seismic resistance of constructions by using alternative artificial bases. Two types of artificial bases are considered: a (consolidated) soil pad and a pile foundation (with or without pile grating). Criteria have been established for the foundation parameters required depending upon the foundation versus construction stiffness ratio. The construction of a consolidated soil pad 3 m thick (h~3m) with deformation module E0 \u3e 30MPa on soils, which are referred, according to the All-Union Building Standard Specifications (SNIP, 1982), to soil category III, is shown to reduce the level of surface accelerations by a factor of 1.5-2. The thickness of a pad for massive stiff structures has to be minimum and provide the bearing capacity of the foundation. In many cases an artificial base in the form of a pile foundation is desirable. This footing is most efficient in construction on a layer of strongly compressible soil 10-15 m thick overlying solid rock. The effects of such an artificial base on the dynamic characteristics of structures, as well as the properties of pile operation are discussed in the present paper

General entanglement

The paper contains a brief review of an approach to quantum entanglement based on analysis of dynamic symmetry of systems and quantum uncertainties, accompanying the measurement of mean value of certain basic observables. The latter are defined in terms of the orthogonal basis of Lie algebra, corresponding to the dynamic symmetry group. We discuss the relativity of entanglement with respect to the choice of basic observables and a way of stabilization of robust entanglement in physical systems.Comment: 7 pages, 1 figure,1 tabe, will be published in special issue of Journal of Physics (Conference Series) with Proceedings of CEWQO-200