{ "id": "math/9808085", "version": "v1", "published": "1998-08-18T22:25:30.000Z", "updated": "1998-08-18T22:25:30.000Z", "title": "On normal subgroups in the fundamental groups of complex surfaces", "authors": [ "Michael Kapovich" ], "categories": [ "math.GT", "math.AG" ], "abstract": "We show that for each aspherical compact complex surface $X$ whose fundamental group $\\pi$ fits into a short exact sequence $$ 1\\to K \\to \\pi \\to \\pi_1(S) \\to 1 $$ where $S$ is a compact hyperbolic Riemann surface and the group $K$ is finitely-presentable, there is a complex structure on $S$ and a nonsingular holomorphic fibration $f: X\\to S$ which induces the above short exact sequence. In particular, the fundamental groups of compact complex-hyperbolic surfaces cannot fit into the above short exact sequence. As an application we give the first example of a non-coherent uniform lattice in $PU(2,1)$.", "revisions": [ { "version": "v1", "updated": "1998-08-18T22:25:30.000Z" } ], "analyses": { "keywords": [ "fundamental group", "short exact sequence", "normal subgroups", "compact hyperbolic riemann surface", "compact complex-hyperbolic surfaces" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "1998math......8085K" } } }