DOI: 10.68381/jca22043 ISSN: 0944-6532

A Sharp Quantitative Estimate for the Perimeters of Convex Sets in the Plane

Menita Carozza, Flavia Giannetti, Francesco Leonetti, Antonia Passarelli di Napoli

Let

E \subset B \subset \mathbb R^2 E ⊂ B ⊂ R 2
be bounded, convex sets. The monotonicity of the perimeters holds, i.e.
\mathcal{H}^{1} (\partial E) \leqslant \mathcal{H}^{1}(\partial B) H 1 ( ∂ E ) ⩽ H 1 ( ∂ B )
. Here we give a quantitative estimate of the difference of the perimeters: it shows how much the perimeter of
B B
increases when
B B
becomes larger and larger with respect to
E E
. We give an example showing that our estimate is sharp.