30 citations · 91 across the 25 of their papers we have counts for
5 papers · 1 filter
Dirichlet-to-Neumann Maps, Abstract Weyl-Titchmarsh -Functions, and a Generalized Index of Unbounded Meromorphic Operator-Valued Functions
Jussi Behrndt, Fritz Gesztesy, Helge Holden +1
We introduce a generalized index for certain meromorphic, unbounded, operator-valued functions. The class of functions is chosen such that energy parameter dependent Dirichlet-to-N…
Stability of square root domains associated with elliptic systems of PDEs on nonsmooth domains
Fritz Gesztesy, Steve Hofmann, Roger Nichols
We discuss stability of square root domains for uniformly elliptic partial differential operators in , with mixed boundary conditions on…
Heat kernel bounds for elliptic partial differential operators in divergence form with Robin-type boundary conditions II
Fritz Gesztesy, Marius Mitrea, Roger Nichols +1
The principal aim of this short note is to extend a recent result on Gaussian heat kernel bounds for self-adjoint $L^2(\Om; d^n x)$-realizations, , , of divergen…
On Stability of Square Root Domains for Non-Self-Adjoint Operators Under Additive Perturbations
Fritz Gesztesy, Steve Hofmann, Roger Nichols
Assuming to be an m-accretive operator in the complex Hilbert space , we use a resolvent method due to Kato to appropriately define the additive perturbation $T…
Heat Kernel Bounds for Elliptic Partial Differential Operators in Divergence Form with Robin-Type Boundary Conditions
Fritz Gesztesy, Marius Mitrea, Roger Nichols
One of the principal topics of this paper concerns the realization of self-adjoint operators $L_{Θ, \Om}$ in $L^2(\Om; d^n x)^m$, , associated with divergence form e…