Brezis Open Problem 9.3

Let N≥1N\ge 1, p∈[1,∞)p\in[1,\infty), γ>0\gamma>0, and let Ω⊂RN\Omega\subset\mathbb{R}^N be a bounded open interval if N=1N=1 or a bounded Lipschitz domain if N≥2N\ge 2. For λ>0\lambda>0, define $

\nGλ,p,γ(u;Ω)=λ∬Ω×Ω1{(x,y): x≠y, ∣u(x)−u(y)∣p∣x−y∣p+γ≥λ}∣x−y∣γ−N dx dy.\nG_{\lambda,p,\gamma}(u;\Omega)=\lambda\iint_{\Omega\times\Omega}\mathbf{1}_{\left\{(x,y):\,x\ne y,\ \frac{|u(x)-u(y)|^p}{|x-y|^{p+\gamma}}\ge\lambda\right\}}|x-y|^{\gamma-N}\,dx\,dy.

IdentifytheIdentify the\Gamma−limitof-limit of G_{\lambda,p,\gamma}(\cdot;\Omega)ininL^p(\Omega)asas\lambda\to\infty,includingthepreciselocallimitingenergyanditsconstant.Theclaimedansweronthesedomainsis, including the precise local limiting energy and its constant. The claimed answer on these domains is

Ψp,γcell(u;Ω)={\nCN,p,γcell∫Ω∣∇u∣p dx,p∈(1,∞), u∈W1,p(Ω),nCN,1,γcell∣Du∣(Ω),p=1, u∈BV(Ω),+∞,otherwise,\Psi_{p,\gamma}^{\mathrm{cell}}(u;\Omega)= \begin{cases}\nC_{N,p,\gamma}^{\mathrm{cell}}\displaystyle\int_\Omega|\nabla u|^p\,dx,&p\in(1,\infty),\ u\in W^{1,p}(\Omega),\\nC_{N,1,\gamma}^{\mathrm{cell}}|Du|(\Omega),&p=1,\ u\in BV(\Omega),\\ +\infty,&\text{otherwise}, \end{cases}

wherethepositiveconstantsareindependentofwhere the positive constants are independent of\Omega$ and are characterized by a cell formula.

References

Progress summary

Refreshed
Claimed solved

A new unrefereed preprint claims to solve the problem on bounded intervals and Lipschitz domains, but the result has not yet been independently verified.

Brezis Open Problem 9.3 concerns identifying the local energy produced by a broad class of thresholded nonlocal functionals.

August 2026 affirmative preprint claim

A preprint dated August 2026 claims the limit is established on bounded intervals and Lipschitz domains, with the constants characterized by cell formulas. If correct, this answers the problem in those settings; the claim is unrefereed and remains unverified.

Current status (as of August 2026): An unrefereed preprint claims an affirmative solution on bounded intervals and Lipschitz domains, while independent verification and the status of any broader formulation remain open.

Sources

Solutions 0

No solutions have been posted yet.