Non degeneracy of blow-up solutions of non-quantized singular Liouville-type equations and the convexity of the mean field entropy of the Onsager vortex model with singular sources
Daniele Bartolucci, Wen Yang, Lei Zhang
TL;DR
This work extends non-degeneracy results for bubbling solutions to singular Liouville-type equations by allowing non-quantized singular sources and mixed blow-up configurations on a Riemann surface. It develops a refined local and global asymptotic analysis (via Green functions, standard bubbles, and Pohozaev-type identities) to show that the linearized operator has trivial kernel, thereby establishing non-degeneracy and enabling strict convexity results for the entropy in the Onsager vortex model with sinks. The authors then harness these analytic insights to characterize existence/non-existence at the critical threshold ρ = 8π(1+β), and to classify domains into first/second kind, proving precise relationships between microcanonical and canonical variational principles and demonstrating entropy maximizers concentrate at the singular sink in the high-energy limit. These results advance the understanding of vortex mean-field limits with singular sources, providing rigorous criteria for thermodynamic equilibria and ensemble equivalence in two-dimensional turbulence models.
Abstract
We establish the non-degeneracy of bubbling solutions for singular mean field equations when the blow-up points are either regular or involve non-quantized singular sources. This extends the results from Bartolucci-Jevnikar-Lee-Yang \cite{bart-5}, which focused on regular blow-up points. As a consequence, we establish the strict convexity of the Entropy in the large energy limit for a specific class of two-dimensional domains in the Onsager mean field vortex model with singular sources.
