2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/115341We introduce the notion of asymptotic cohomology based on the bounded cohomology and define cohomological asymptotic dimension $\as_{\Z} X$ of metric spaces. We show that it agrees with the asymptotic dimension $\as X$ when the later is finite. Then we use this fact to construct an example of a metric space $X$ of bounded geometry with finite asymptotic dimension for which $\as(X\times\R)=\as X$. In particular, it follows for this example that the coarse asymptotic dimension defined by means of Roe's coarse cohomology is strictly less than its asymptotic dimension.30 pagesMetric GeometryGeometric Topology55M10, 20F69, 51F99, 57M20Cohomological approach to asymptotic dimensiontext