3 citations · 5 across the 4 of their papers we have counts for
4 papers
A distance between operators acting in different Hilbert spaces and operator convergence
Olaf Post, Jan Simmer
The aim of the present article is to give an introduction to the concept of quasi-unitary equivalence and to define several (pseudo-)metrics on the space of self-adjoint operators…
Quasi-unitary equivalence and generalised norm resolvent convergence
Olaf Post, Jan Simmer
The purpose of this article is to give a short introduction to the concept of quasi-unitary equivalence of quadratic forms and its consequences. In particular, we improve an estima…
Approximation of fractals by manifolds and other graph-like spaces
Olaf Post, Jan Simmer
We define a distance between energy forms on a graph-like metric measure space and on a discrete weighted graph using the concept of quasi-unitary equivalence. We apply this result…
Approximation of fractals by discrete graphs: norm resolvent and spectral convergence
Olaf Post, Jan Simmer
We show a norm convergence result for the Laplacian on a class of post-critically finite fractals with arbitrary Borel regular probability measure which can be approximated by a se…