{ "id": "1609.02131", "version": "v1", "published": "2016-09-07T19:34:13.000Z", "updated": "2016-09-07T19:34:13.000Z", "title": "A new lower bound for Garsia's entropy of Bernoulli convolutions", "authors": [ "Kevin G. Hare", "Nikita Sidorov" ], "comment": "8 pages, no figures", "categories": [ "math.DS", "math.CA" ], "abstract": "Let $\\beta\\in(1,2)$ and let $H_\\beta$ denote Garsia's entropy for the Bernoulli convolution $\\mu_\\beta$ associated with $\\beta$. In the present paper we show that $H_\\beta>0.82$ for all $\\beta \\in (1, 2)$ and improve this bound for certain ranges. Combined with a recent result by Hochman, this yields $\\dim (\\mu_\\beta)>0.82$ for all algebraic $\\beta$. In addition, we show that if an algebraic $\\beta$ is such that $[\\mathbb{Q}(\\beta): \\mathbb{Q}(\\beta^k)] = k$ for some $k \\geq 2$, then $\\dim(\\mu_\\beta)=1$. Such is, for instance, any root of a Pisot number which is not a Pisot number itself.", "revisions": [ { "version": "v1", "updated": "2016-09-07T19:34:13.000Z" } ], "analyses": { "subjects": [ "26A30", "11R06" ], "keywords": [ "bernoulli convolution", "lower bound", "pisot number", "denote garsias entropy" ], "note": { "typesetting": "TeX", "pages": 8, "language": "en", "license": "arXiv", "status": "editable" } } }