Given a probability distribution {pi}i 1,2,...,W , that is, 0 ≤ pi ≤ 1 i 1, 2, . . . ,W and ∑W i 1 pi 1, the ordinary expectation value of a quantity Q of a system under consideration is defined by ∑W i 1 piQi, where W is the total number of accessible states and is enormously large in statistical mechanics, typically being 210 23 . In the field of generalized statistical mechanics for complex ...

Quantum discord characterizes "nonclassicality" of correlations in quantum mechanics. It has been proposed as the key resource present in certain quantum communication tasks and quantum computational models without containing much entanglement. We obtain a necessary and sufficient condition for the existence of nonzero quantum discord for any dimensional bipartite states. This condition is easi...

We present explicit examples to show that the ‘compatibility criterion’ [recently obtained by us towards providing equilibrium configurations compatible with the structure of general relativity] which states that: for a given value of σ[≡ (P0/E0) ≡ the ratio of central pressure to central energy-density], the compactness ratio u[≡ (M/R), whereM is the total mass andR is the radius of the config...

The problem considered in this paper is whether the capacity of a discrete time Gaussian channel is increased by feedback or not. It is well known that the capacity of a white Gaussian channel under the average power constraint is not changed by feedback. In the previous paper [7] we gave some sufficient conditions under which the capacity of a non-white Gaussian channel is increased by feedbac...

A necessary and sufficient condition is given for the exact reduction of systems modeled by linear fractional transformations (LFT’s) on structured operator sets. This condition is based on the existence of a rank-deficient solution to either of a pair of linear matrix inequalities which generalize Lyapunov equations; the notion of Gramians is thus also generalized to uncertain systems, as well...

Under what conditions can potential contestants avoid conflicts through a peace settlement? This question is relevant to real world situations such as international conflicts and pre-litigation negotiations. In the spirit of Myerson and Satterthwaite [4] on bilateral trade, where information asymmetry is the impediment to mutually beneficial negotiation outcomes, a natural approach to address t...