Admissible solutions of the 2D Onsager's conjecture (2506.15396v1)

Abstract: We show that for any $\gamma < \frac{1}{3}$ there exist H\"{o}lder continuous weak solutions $v \in C^{\gamma}([0,T] \times \mathbb{T}^2)$ of the two-dimensional incompressible Euler equations that strictly dissipate the total kinetic energy, improving upon the elegant work of Giri and Radu [Invent. Math., 238 (2), 2024]. Furthermore, we prove that the initial data of these \textit{admissible} solutions are dense in $B^{\gamma}_{\infty,r<\infty}$. Our approach introduces a new class of traveling waves, refining the traditional temporal oscillation function first proposed by Cheskidov and Luo [Invent. Math., 229(3), 2022], to effectively modulate energy on any time intervals. Additionally, we propose a novel ``multiple iteration scheme'' combining Newton-Nash iteration with a Picard-type iteration to generate an energy corrector for controlling total kinetic energy during the perturbation step. This framework enables us to construct dissipative weak solutions below the Onsager critical exponent in any dimension $d \geq 2$.