Besicovitch inequality explained

In mathematics, the Besicovitch inequality is a geometric inequality relating volume of a set and distances between certain subsets of its boundary. The inequality was first formulated by Abram Besicovitch.[1]

Consider the n-dimensional cube

[0,1]n

with a Riemannian metric

g

. Let denote the distance between opposite faces of the cube. The Besicovitch inequality asserts that The inequality can be generalized in the following way. Given an n-dimensional Riemannian manifold M with connected boundary and a smooth map

f:M[0,1]n

, such that the restriction of f to the boundary of M is a degree 1 map onto

\partial[0,1]n

, define Then

\prodidi\geqVol(M)

.

The Besicovitch inequality was used to prove systolic inequalitieson surfaces.[2] [3]

References

Notes and References

  1. A. S. Besicovitch, On two problems of Loewner, J. London Math. Soc. 27 (1952) 141–144.
  2. Mikhael Gromov. Filling Riemannian manifolds. J. Differential Geom. 18 (1983), no. 1, 1-147.
  3. P. Papasoglu, Cheeger constants of surfaces and isoperimetric inequalities, Trans. Amer. Math. Soc. 361 (2009) 5139–5162.