{ "id": "1207.7249", "version": "v3", "published": "2012-07-31T14:06:35.000Z", "updated": "2013-06-17T11:33:10.000Z", "title": "Non-existence of tight neighborly manifolds with $β_1=2$", "authors": [ "Nitin Singh" ], "comment": "8 pages. arXiv admin note: text overlap with arXiv:1102.0856, arXiv:1207.5599 by other authors", "categories": [ "math.GT", "math.CO" ], "abstract": "For $d\\geq 2$, Walkup's class $\\Kd$ consists of the $d$-dimensional simplicial complexes whose vertex-links are stacked $(d-1)$-spheres. Recently Lutz, Sulanke and Swartz have shown that all $\\mathbb{F}$-orientable triangulated $d$-manifolds satisfy the inequality $\\binom{f_0-d-1}{2} \\geq \\binom{d+2}{2}\\beta_1$ for $d\\geq 3$. They call a $d$-manifold \\emph{tight neighborly} if it attains the equality in the bound. For $d\\geq 4$, tight neighborly $d$-manifolds are precisely the 2-neighborly members of $\\Kd$. In this paper we show that there does not exist any tight neighborly $d$-manifold with $\\beta_1=2$.", "revisions": [ { "version": "v3", "updated": "2013-06-17T11:33:10.000Z" } ], "analyses": { "subjects": [ "57Q15", "57R05" ], "keywords": [ "tight neighborly manifolds", "non-existence", "dimensional simplicial complexes", "walkups class", "manifolds satisfy" ], "note": { "typesetting": "TeX", "pages": 8, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1207.7249S" } } }