8
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357 views

Is $SO_2$ an amenable group?

In S. Wagon's "The Banach-Tarski Paradox," amenable groups are defined on p. 12 as follows: [amenable] groups bear a left-invariant, finitely additive measure of total measure one that is defined ...
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3answers
455 views

A soft Question Suggestions for good introductory books

This question has been edited in view of comments received.Hope it is better now. Consider the set of all points on the circumference of a circle and the set of all points inside a circle. what is ...