A better proof of the Goldman-Parker conjecture.
We present a short and self-contained proof of the extension property for partial isometries of the class of all finite metric spaces.
We report on a partial solution of the conjecture that the class of finite solvable groups can be characterised by 2-variable identities. The proof requires pieces from number theory, algebraic geometry, singularity theory and computer algebra. The computations were carried out using the computer algebra system SINGULAR.
Let be a field with a Krull valuation and value group , and let be the valuation ring. Theories about spaces of countable type and Hilbert-like spaces in [1] and spaces of continuous linear operators in [2] require that all absolutely convex subsets of the base field should be countably generated as -modules.By [1] Prop. 1.4.1, the field is metrizable if and only if the value group has a cofinal sequence. We prove that for any fixed cardinality , there exists a metrizable field ...
We prove that an Artin-Tits group of type is the group of fractions of a Garside monoid, analogous to the known dual monoids associated with Artin-Tits groups of spherical type and obtained by the “generated group” method. This answers, in this particular case, a general question on Artin-Tits groups, gives a new presentation of an Artin-Tits group of type , and has consequences for the word problem, the computation of some centralizers or the triviality of the center. A key point of the proof...