Dilations and interaction

Dilations and constrained algebras

It is well known that contractive representations of the disk algebra are completely contractive. Let A denote the subalgebra of the disk algebra consisting of those functions f for which f ′(0) = 0. We prove that there are contractive representations of A which are not completely contractive, and furthermore characterize those contractive representations which are completely contractive.

Disjoinable Lagrangian Spheres and Dilations

We consider open symplectic manifolds which admit dilations (in the sense previously introduced by Solomon and the author). We obtain restrictions on collections of Lagrangian submanifolds which are pairwise disjoint (or pairwise disjoinable by Hamiltonian isotopies) inside such manifolds. This includes the Milnor fibres of isolated hypersurface singularities which have been stabilized (by addi...

Paschke Dilations

Wavelets with Composite Dilations

A wavelet with composite dilations is a function generating an orthonormal basis or a Parseval frame for L2(Rn) under the action of lattice translations and dilations by products of elements drawn from non-commuting matrix sets A and B. Typically, the members of B are shear matrices (all eigenvalues are one) while the members of A are matrices expanding or contracting on a proper subspace of Rn...

Polyomorphisms Conjugate to Dilations