{ "id": "1510.02242", "version": "v1", "published": "2015-10-08T09:06:56.000Z", "updated": "2015-10-08T09:06:56.000Z", "title": "Some remarks on the uniqueness of the complex projective spaces", "authors": [ "Ping Li" ], "comment": "7 pages", "categories": [ "math.DG", "math.AT" ], "abstract": "We first notice in this article that if a compact K\\\"{a}hler manifold has the same integral cohomology ring and Pontrjagin classes as the complex projective space $\\mathbb{C}P^n$, then it is biholomorphic to $\\mathbb{C}P^n$ provided $n$ is odd. The same holds for even $n$ if we further assume that $M$ is simply-connected. This technically refines a classical result of Hirzebruch-Kodaira and Yau. This observation, together with a result of Dessai and Wilking, enables us to characterize all $\\mathbb{C}P^n$ in terms of homotopy type under mild symmetry. When $n=4$, we can drop the requirement on Pontrjagin classes by showing that a simply-connected compact K\\\"{a}hler manifold having the same integral cohomology ring as $\\mathbb{C}P^4$ is biholomorphic to $\\mathbb{C}P^4$, which improves on results of Fujita and Libgober-Wood.", "revisions": [ { "version": "v1", "updated": "2015-10-08T09:06:56.000Z" } ], "analyses": { "subjects": [ "32Q15", "53C55", "32Q55" ], "keywords": [ "complex projective space", "pontrjagin classes", "integral cohomology ring", "uniqueness", "mild symmetry" ], "note": { "typesetting": "TeX", "pages": 7, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2015arXiv151002242L" } } }