Sumset phenomenon in countable amenable groups
نویسندگان
چکیده
منابع مشابه
The Sumset Phenomenon
Answering a problem posed by Keisler and Leth, we prove a theorem in nonstandard analysis to reveal a phenomenon about sumsets, which says that if two sets A and B are large in terms of \measure", then the sum A+B is not small in terms of \order{topology". The theorem has several corollaries about sumset phenomenon in the standard world; these are described in sections 2{4. One of these is a ne...
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ژورنال
عنوان ژورنال: Advances in Mathematics
سال: 2010
ISSN: 0001-8708
DOI: 10.1016/j.aim.2009.08.009