Rigidity sequences, Kazhdan sets and group topologies on the integers
نویسندگان
چکیده
We study the relationships between three different classes of sequences (or sets) integers, namely rigidity sequences, Kazhdan and nullpotent sequences. prove that are non-Kazhdan nullpotent, all other implications false. In particular, we show by probabilistic means there exist integers which both Kazhdan. Moreover, using Baire category methods, provide general criteria for a sequence to be sequence. Finally, give new proof existence dense in ℤ Bohr topology, result originally due Griesmer.
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ژورنال
عنوان ژورنال: Journal D Analyse Mathematique
سال: 2021
ISSN: ['0021-7670', '1565-8538']
DOI: https://doi.org/10.1007/s11854-021-0165-4