Nonuniqueness

Vanishing viscosity and nonuniqueness

Non-unique vanishing-viscosity solutions of 2D Euler with vorticity in Lp

A manuscript claiming two distinct weak Euler solutions arising as vanishing-viscosity limits from the same compactly supported initial vorticity, for every 2 < p < ∞.

Two distinct vanishing-viscosity limits

This manuscript contains a claim of the following result:

Theorem

For every p ∈ (2, ∞), there exists a compactly supported vorticity ωin∈Lp(ℝ2) and a sequence of viscosities {νn}n ∈ ℕ with νn ↓ 0 as n → ∞, such that the associated solutions of the 2D Navier-Stokes equations in vorticity form

{∂tωνn+uνn·∇ωνn=νnΔωνn,ωνn|t=0=ωin,

satisfy

ων2n→ωe,
ων2n+1→ωo,
ωe≠ωo.

The convergences hold in the space C([0,T];Lp(ℝ2)) for some T ∈ (0, ∞), and ωe, ωo are two distinct weak solutions of the 2D Euler equations with initial vorticity ωin.

Read the full argument

Non-unique vanishing-viscosity selection for planar Euler

The revised manuscript is available below. The source material brings together the original chat, prompts, manuscript versions, and the complete source ZIP with its SHA-256 checksum.

Our purpose

We are sharing the manuscript here because we would like the mathematics behind this result to be prioritized over a counterproductive race to upload AI-generated proofs to arXiv.

We are organizing a reading group to study the claimed proof in detail, identify and deeply understand its main underlying ideas, and communicate them in a form more accessible to the mathematical community, for instance as a set of lecture notes.