The integral cohomology of the group of loops

Jensen, Craig A¹ ; McCammond, Jon² ; Meier, John³

¹ Department of Mathematics, University of New Orleans, New Orleans, LA 70148, USA
² Department of Mathematics, University of California, Santa Barbara, CA 93106, USA
³ Deptartment of Mathematics, Lafayette College, Easton, PA 18042, USA

Geometry & topology, Tome 10 (2006) no. 2, pp. 759-784.

Résumé

Let $\text{ P}{\Sigma }_n$ denote the group that can be thought of either as the group of motions of the trivial $n$–component link or the group of symmetric automorphisms of a free group of rank $n$. The integral cohomology ring of $\text{ P}{\Sigma }_n$ is determined, establishing a conjecture of Brownstein and Lee.

Détail

DOI : 10.2140/gt.2006.10.759

Keywords: nonpositive curvature, CAT(0), decidability

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