Peter Walters

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0. Introduction. Considerable progress has been made in the classification of measure preserving transformations during the last thirteen years, reaching a high point with the recent work of Ornstein [1]. Most of this theory has concentrated on invertible transformations (automorphisms) since it was here that the essential problems awaited solution. Viewed(More)
A measurement of two-particle correlations with a high transverse momentum trigger particle (p(T)(trig) > 2.5 GeV/c) is presented for Au+Au collisions at square root(s(NN)) = 200 GeV over the uniquely broad longitudinal acceptance of the PHOBOS detector (-4 < Delta eta < 2). A broadening of the away-side azimuthal correlation compared to elementary(More)
When T :X −→X is a one-sided topologically mixing subshift of finite type and φ :X −→R is a continuous function, one can define the Ruelle operator Lφ :C(X)−→C(X) on the space C(X) of real-valued continuous functions on X. The dual operator Lφ always has a probability measure ν as an eigenvector corresponding to a positive eigenvalue (Lφν=λν with λ> 0).(More)
The potential of 3D printing has been under technical and philosophical discussion for some time, but current rapid prototyping materials can be costly and are limited in terms of functional and visual qualities. Food-based materials could provide a novel and exciting alternative which may also be affordable and accessible as 3d printing extends from(More)
In this paper, we show that each expanding Thurston map f : S → S has 1 + deg f fixed points, counted with appropriate weight, where deg f denotes the topological degree of the map f . We then prove the equidistribution of preimages and of (pre)periodic points with respect to the unique measure of maximal entropy μf for f . We also show that (S , f, μf ) is(More)
Introduction. Automorphisms and, more generally, affine transformations of nilmanifolds exhibit many interesting properties. For example, hyperbolic automorphisms serve as basic examples of Anosov diffeomorphisms [6], ergodic automorphisms are Kolmogorov automorphisms [5], and ergodic rotations are examples of transformations with mixed spectrum which do(More)
Introduction. In Section 1 we define continuous maps with unstable centralizers and homeomorphisms with discrete centralizers. Expansive homeomorphisms, which have recently been of interest to several authors, have discrete centralizers. In Section 2 we obtain necessary and sufficient conditions for affine transformations of nilmanifolds to have discrete(More)