{ "id": "1205.2515", "version": "v1", "published": "2012-05-11T13:14:26.000Z", "updated": "2012-05-11T13:14:26.000Z", "title": "A short proof of Paouris' inequality", "authors": [ "Radosław Adamczak", "Rafał Latała", "Alexander E. Litvak", "Krzysztof Oleszkiewicz", "Alain Pajor", "Nicole Tomczak-Jaegermann" ], "categories": [ "math.PR", "math.MG" ], "abstract": "We give a short proof of a result of G. Paouris on the tail behaviour of the Euclidean norm $|X|$ of an isotropic log-concave random vector $X\\in\\R^n$, stating that for every $t\\geq 1$, $P(|X|\\geq ct\\sqrt n)\\leq \\exp(-t\\sqrt n)$. More precisely we show that for any log-concave random vector $X$ and any $p\\geq 1$, $(E|X|^p)^{1/p}\\sim E |X|+\\sup_{z\\in S^{n-1}}(E |< z,X>|^p)^{1/p}$.", "revisions": [ { "version": "v1", "updated": "2012-05-11T13:14:26.000Z" } ], "analyses": { "subjects": [ "46B06", "46B09", "52A23" ], "keywords": [ "short proof", "inequality", "isotropic log-concave random vector", "euclidean norm", "tail behaviour" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1205.2515A" } } }