Finitely generated rings obtained from hyperrings through the fundamental relations

In this article, we introduce and analyze a strongly regular relation $\omega^{*}_{\mathcal{A}}$ on a hyperring$R$ such that in a particular case we have $|R/\omega^{*}_{\mathcal{A}}|\leq 2$ or$R/\omega^{*}_{\mathcal{A}}=<\omega^{*}_{\mathcal{A}}(a)>$, i.e., $R/\omega^{*}_{\mathcal{A}}$ is a finite generated ring. Then, by using the notion of $\omega^{*}_{\mathcal{A}}$-parts, we investigate the transitivity condition of $\omega_{\mathcal{A}}$. Finally, we investigate a strongly regular relation $\chi^{*}_{\mathcal{A}}$ on the hyperring $R$ such that $R/\chi^{*}_{\mathcal{A}}$ is a commutative ring with finite generated.

Cyclic Groups Obtained as Quotient Hypergroups

We introduce a strongly regular equivalence relation ρ*A on the hypergroup H, such that in a particular case the quotient is a cyclic group. Then by using the notion of ρ*A-parts, we investigate the transitivity condition of ρA. Finally, a characterization of the derived hypergroup Dc(H) has been considered.

Chaotic and ergodic properties of cylindric billiards

Chaotic and ergodic properties are discussed for various subclasses of cylindric billiards. A common feature of the studied systems is that they satisfy a natural necessary condition for ergodicity and hyperbolicity, the so-called transitivity condition. The relation of our discussion to former results on hard ball systems is twofold. On the one hand, by slight adaptation of the proofs we may discuss hyperbolic and ergodic properties of 3 or 4 particles with (possibly restricted) hard ball interactions in any dimensions. On the other hand, a key tool in our investigations is a kind of connected path formula for cylindric billiards, which together with the conservation of momenta gives back, when applied to the special case of hard ball systems, the classical connected path formula.

The Livšic periodic point theorem for non-abelian cocycles

For hyperbolic systems and for Hölder cocycles with values in a compact metric group, we extend Livšic's periodic point characterisation of coboundaries. Here we show that two such cocycles are cohomologous when their respective ‘weights’ (of closed orbits) coincide. When it is only assumed that they are conjugate, one of the cocycles must (in general) be modified by an isomorphism (which stabilises conjugacy classes) to obtain cohomology. When the group is Lie and when a transitivity condition is satisfied, conjugacy of weights ensures that the cocycles are cohomologous with respect to a finitely extended group.

Subjective Risk and Choice as Related to the Transitivity Condition

Subjects who did not break the transitivity condition in a simple choice situation showed a significant linear relation between choice and their rating of risk, an ordinal scale of risk in other choice situations, a self-reported level of risk taking related to the choices made. Subjects breaking transitivity did not fulfill the above conditions and were more random in choice and reported that they made risky choices. In fact there was no significant difference between the transitive and non-transitive subjects in the number of risky choices made throughout the experiment.