 

Ameer Athavale
A multivariate generalization of the von NeumannWold decomposition view print


Published: 
January 11, 2018

Keywords: 
Spherical isometry, qhypercontraction 
Subject: 
Primary 47A13 


Abstract
Let H be a complex infinitedimensional separable Hilbert space. If T is an isometry acting on H, then the von NeumannWold decomposition theorem asserts that T can be expressed as a direct sum of the unilateral shift (of some multiplicity) and a unitary operator. We establish a multivariate generalization of the von NeumannWold decomposition and explore some of the implications of that generalization. In particular we derive a universal representation theorem for members of a special class of spherical isometries and verify that any member of that class is hyperreflexive.


Author information
Department of Mathematics, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
athavale@math.iitb.ac.in

