%0 Journal Article %T Comparing seminorms on homology %+ Mathematics Department, The Ohio State University %+ Laboratoire d'Analyse, Topologie, Probabilités (LATP) %A Lafont, Jean-François %A Pittet, Christophe %< avec comité de lecture %@ 0030-8730 %J Pacific Journal of Mathematics %I Mathematical Sciences Publishers %V 259 %N 2 %P 373--385 %8 2012 %D 2012 %R 10.2140/pjm.2012.259.373 %K /1-norm %K simplicial volume %K singular homology %K manifold norm %K Steenrod’s realization problem %K Thurston norm %K Tomei manifold %Z 53C23; 57M50 %Z Mathematics [math]/Differential Geometry [math.DG]Journal articles %X We compare the l1-seminorm ̇1 and the manifold seminorm ̇man on n-dimensional integral homology classes. Crowley and Löh showed that for any topological space X and any α ε Hn.(X;Z) with n ≠ 3, the equality αman =α1 holds. We compute the simplicial volume of the 3-dimensional Tomei manifold and apply Gaifullin's desingularization to establish the existence of a constant δ3≈0.0115416, with the property that for any X and any α εH3(XI Z) one has the inequality. %G English %L hal-01305010 %U https://hal.science/hal-01305010 %~ CNRS %~ UNIV-AMU %~ EC-MARSEILLE %~ INSMI