We consider a cosmological model consisting of two scalar fields defined in the hyperbolic plane known as inflation. For background space, we homogeneous and isotropic spacetime with nonzero curvature. study asymptotic behaviour solutions search for attractors expanding regime. prove that inflationary stages are stable can solve flatness problem describe acceleration both open closed models, ad...

‎In this paper we characterize Bergman spaces with‎ ‎respect to double integral of the functions $|f(z)‎ ‎-f(w)|/|z-w|$,‎ ‎$|f(z)‎ -‎f(w)|/rho(z,w)$ and $|f(z)‎ ‎-f(w)|/beta(z,w)$,‎ ‎where $rho$ and $beta$ are the pseudo-hyperbolic and hyperbolic metrics‎. ‎We prove some necessary and sufficient conditions that implies a function to be...

We show that in the Klein projective ball model of hyperbolic space, the hyperbolic Voronoi diagram is affine and amounts to clip a corresponding power diagram, requiring however algebraic arithmetic. By considering the lesser-known Beltrami hemisphere model of hyperbolic geometry, we overcome the arithmetic limitations of Klein construction. Finally, we characterize the bisectors and geodesics...

One area that is often overlooked by economists and social scientists is discounting. Most economic models of intertemporal choice make use of Samuelson’s (1937) DU model which leads to an exponential discount function. Divergences from what economic modelling predicts and empirical findings are on the most part attributed to factors other than the discount function employed. We review the lite...

If G is a word hyperbolic group of cohomological dimension 2, then every subgroup of G of type FP2 is also word hyperbolic. Isoperimetric inequalities are denned for groups of type FP2 and it is shown that the linear isoperimetric inequality in this generalized context is equivalent to word hyperbolicity. A sufficient condition for hyperbolicity of a general graph is given along with an applica...