4 papers
math.AP2026
On chain rule and renormalization
Roman V. Dribas, Nikolay A. Gusev
We discuss the relationship between the chain rule for the divergence operator and the renormalization property for weak solutions of the continuity equation. We construct an examp…
math.AP2025
The Nelson conjecture and chain rule property
Nikolay A. Gusev, Mikhail V. Korobkov
Let and let be a compactly supported vector field with and $\operatorname{div} \b…
math.CA2025
Nowhere monotone Riemann integrable derivative without local extrema
Nikolay A. Gusev, Andrey E. Komagorov
We construct a nowhere monotone Riemann integrable derivative which has no local extrema. We also construct a differentiable function such that is Riemann integrable and h…
math.AP2025
On the weak Sard property
Roman V. Dribas, Andrew S. Golovnev, Nikolay A. Gusev
If is of class then Sard's theorem implies that has the following relaxed Sard property: the image under of the Lebesgue measure rest…