Quadratic forms

Eutactic lattice

In mathematics, a eutactic lattice (or eutactic form) is a lattice in Euclidean space whose minimal vectors form a eutactic star. This means they have a set of positive eutactic coefficients ci such that (v, v) = Σci(v, mi)2 where the sum is over the minimal vectors mi. "Eutactic" is derived from the Greek language, and means "well-situated" or "well-arranged". proved that a lattice is extreme if and only if it is both perfect and eutactic. summarize the properties of eutactic lattices of dimension up to 7. (Wikipedia).

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Related pages

Perfect lattice | Lattice (group) | Eutactic star | Euclidean space