Main article: Minkowski's theorem
Suppose that Γ {\displaystyle \Gamma } is a lattice in n {\displaystyle n} -dimensional Euclidean space R n {\displaystyle \mathbb {R} ^{n}} and K {\displaystyle K} is a convex centrally symmetric body. Minkowski's theorem, sometimes called Minkowski's first theorem, states that if vol ( K ) > 2 n vol ( R n / Γ ) {\displaystyle \operatorname {vol} (K)>2^{n}\operatorname {vol} (\mathbb {R} ^{n}/\Gamma )} , then K {\displaystyle K} contains a nonzero vector in Γ {\displaystyle \Gamma } .
Main article: Minkowski's second theorem
The successive minimum λ k {\displaystyle \lambda _{k}} is defined to be the inf of the numbers λ {\displaystyle \lambda } such that λ K {\displaystyle \lambda K} contains k {\displaystyle k} linearly independent vectors of Γ {\displaystyle \Gamma } . Minkowski's theorem on successive minima, sometimes called Minkowski's second theorem, is a strengthening of his first theorem and states that4
In 1930–1960 research on the geometry of numbers was conducted by many number theorists (including Louis Mordell, Harold Davenport and Carl Ludwig Siegel). In recent years, Lenstra, Brion, and Barvinok have developed combinatorial theories that enumerate the lattice points in some convex bodies.5
Main article: Subspace theorem
See also: Siegel's lemma, volume (mathematics), determinant, and parallelepiped
In the geometry of numbers, the subspace theorem was obtained by Wolfgang M. Schmidt in 1972.6 It states that if n is a positive integer, and L1,...,Ln are linearly independent linear forms in n variables with algebraic coefficients and if ε>0 is any given real number, then the non-zero integer points x in n coordinates with
lie in a finite number of proper subspaces of Qn.
Main article: normed vector space
See also: Banach space and F-space
Minkowski's geometry of numbers had a profound influence on functional analysis. Minkowski proved that symmetric convex bodies induce norms in finite-dimensional vector spaces. Minkowski's theorem was generalized to topological vector spaces by Kolmogorov, whose theorem states that the symmetric convex sets that are closed and bounded generate the topology of a Banach space.7
Researchers continue to study generalizations to star-shaped sets and other non-convex sets.8
MSC classification, 2010, available at http://www.ams.org/msc/msc2010.html, Classification 11HXX. http://www.ams.org/msc/msc2010.html ↩
Minkowski, Hermann (2013-08-27). Space and Time: Minkowski's papers on relativity. Minkowski Institute Press. ISBN 978-0-9879871-1-2. 978-0-9879871-1-2 ↩
Schmidt's books. Grötschel, Martin; Lovász, László; Schrijver, Alexander (1993), Geometric algorithms and combinatorial optimization, Algorithms and Combinatorics, vol. 2 (2nd ed.), Springer-Verlag, Berlin, doi:10.1007/978-3-642-78240-4, ISBN 978-3-642-78242-8, MR 1261419 978-3-642-78242-8 ↩
Cassels (1971) p. 203 ↩
Grötschel et al., Lovász et al., Lovász, and Beck and Robins. ↩
Schmidt, Wolfgang M. Norm form equations. Ann. Math. (2) 96 (1972), pp. 526–551. See also Schmidt's books; compare Bombieri and Vaaler and also Bombieri and Gubler. ↩
For Kolmogorov's normability theorem, see Walter Rudin's Functional Analysis. For more results, see Schneider, and Thompson and see Kalton et al. ↩
Kalton et al. Gardner ↩