The Fedosov manifolds and magnetic monopole

A non-symplectic generalization of Hamiltonian mechanics is considered. It allows include into consideration "non-Lagrange" systems, such as theory of charged particle in the field of magnetic monopole. The corresponding generalization for the Fedosov manifolds is given. The structure of phase space of "charged particle in the field of magnetic monopole" is studied.Comment: 14 page

Mean-Set Attack: Cryptanalysis of Sibert et al. Authentication Protocol

We analyze the Sibert et al. group-based (Feige-Fiat-Shamir type) authentication protocol and show that the protocol is not computationally zero-knowledge. In addition, we provide experimental evidence that our approach is practical and can succeed even for groups with no efficiently computable length function such as braid groups. The novelty of this work is that we are not attacking the protocol by trying to solve an underlying complex algebraic problem, namely, the conjugacy search problem, but use a probabilistic approach, instead

A new key exchange protocol based on the decomposition problem

In this paper we present a new key establishment protocol based on the decomposition problem in non-commutative groups which is: given two elements $w, w_1$ of the platform group $G$ and two subgroups $A, B \subseteq G$ (not necessarily distinct), find elements $a \in A, b \in B$ such that $w_1 = a w b$. Here we introduce two new ideas that improve the security of key establishment protocols based on the decomposition problem. In particular, we conceal (i.e., do not publish explicitly) one of the subgroups $A, B$, thus introducing an additional computationally hard problem for the adversary, namely, finding the centralizer of a given finitely generated subgroup.Comment: 7 page

Determination of the real exchange rate of rouble and assessment of long-rum policy of real exchange rate targeting

The equilibrium real exchange rate of Russian ruble is estimated for the period from the beginning of 1995 to the beginning of 2008. According to the methodological approach proposed by Edwards (1988) the equilibrium real exchange rate is a function of a set of fundamental variables (so-called “reduced form equation”). In order to estimate an equilibrium real exchange rate a set of fundamentals was selected: terms of trade, productivity differential, fiscal policy variable. Estimation was performed in a cointegrated VAR framework using the Johansen cointegration test. The speed of adjustment of the actual real exchange rate to the equilibrium real exchange rate as well as the influence of monetary policy and private capital flows on the short-run dynamics of real exchange rate is explored.macroeconomics, real exchange rate, Russia