EN
Supposing that the metric space in question supports a fractional diffusion, we prove that after introducing an appropriate multiplicative factor, the Gagliardo seminorms $||f||_{W^{σ,2}}$ of a function f ∈ L²(E,μ) have the property
$1/C ℰ(f,f) ≤ lim inf_{σ↗1} (1−σ)||f||_{W^{σ,2}} ≤ lim sup_{σ↗1}(1−σ) ||f||_{W^{σ,2}} ≤ Cℰ(f,f)$,
where ℰ is the Dirichlet form relative to the fractional diffusion.