Degree Department

Existence and nonexistence of radial solutions for semilinear equations with bounded nonlinearities on exterior domains (open access)

Existence and nonexistence of radial solutions for semilinear equations with bounded nonlinearities on exterior domains

Article studies radial solutions of ∆u + K(r)f(u) = 0 on the exterior of the ball of radius R > 0 centered at the origin in ℝᶰ where f is odd with f < 0 on (0, β), f > 0 on (β, δ), f ≡ 0 for u > δ, and where the function K(r) is assumed to be positive and K(r) → 0 as r → ∞.
Date: December 1, 2020
Creator: Iaia, Joseph A.
System: The UNT Digital Library
On Polish groups admitting non-essentially countable actions (open access)

On Polish groups admitting non-essentially countable actions

Article addresses the question whether every Polish group that is not locally compact admits a Borel action on a standard Borel space whose associated orbit equivalence relation is not essentially countable. The authors e answer this question positively for the class of all Polish groups that embed in the isometry group of a locally compact metric space.
Date: September 17, 2019
Creator: Kechris, Alexander S.; Malicki, Maciej; Panagiotopoulos, Aristotelis & Zielinski, Joseph
System: The UNT Digital Library