ArticleOriginal scientific text

Title

The generic transformation has roots of all orders

Authors 1

Affiliations

  1. University of Florida, PO Box 118105 Gainesville, FL 32611-2082, U.S.A.

Abstract

In the sense of the Baire Category Theorem we show that the generic transformation T has roots of all orders (RAO theorem). The argument appears novel in that it proceeds by establishing that the set of such T is not meager - and then appeals to a Zero-One Law (Lemma 2). On the group Ω of (invertible measure-preserving) transformations, §D shows that the squaring map p: S → S^{2} is topologically complex in that both the locally-dense and locally-lacunary points of p are dense (Theorem 23). The last section, §E, discusses the relation between RAO and a recent example of Blair Madore. Answering a question of the author's, Madore constructs a transformation with a square-root chain of each finite length, yet possessing no infinite square-root chain.

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Pages:
521-547
Main language of publication
English
Received
1999-11-08
Accepted
2000-02-20
Published
2000
Exact and natural sciences