22 citations · 62 across the 13 of their papers we have counts for
13 papers
Piecewise isometry groups of Euclidean tessellations
Robert Bieri, Alex Feingold, Daniel Studenmund
Given a tessellation of Euclidean or hyperbolic space, the piecewise isometry group is the group whose elements are given by cutting space into finitely many tessellated convex sub…
Decompositions of hyperbolic Kac-Moody algebras with respect to imaginary root groups
Alex J. Feingold, Axel Kleinschmidt, Hermann Nicolai
We propose a novel way to define imaginary root subgroups associated with (timelike) imaginary roots of hyperbolic Kac-Moody algebras. Using in an essential way the theory of unita…
A Lightcone Embedding of the Twin Building of a Hyperbolic Kac-Moody Group
Lisa Carbone, Alex J. Feingold, Walter Freyn
Let A be a symmetrizable hyperbolic generalized Cartan matrix with Kac-Moody algebra g = g(A) and (adjoint) Kac-Moody group G = G(A)=$\langle\exp(ad(t e_i)), \exp(ad(t f_i)) \,|\,…
Weyl groups of some hyperbolic Kac-Moody algebras
Alex J. Feingold, Daniel Vallières
We use the theory of Clifford algebras and Vahlen groups to study Weyl groups of hyperbolic Kac-Moody algebras T_n^{++}, obtained by a process of double extension from a Cartan mat…
The 3-state Potts model and Rogers-Ramanujan series
Alex Feingold, Antun Milas
We explain the appearance of Rogers-Ramanujan series inside the tensor product of two basic -modules, previously discovered by the first author in [F]. The key new ingre…
Hyperbolic Weyl groups and the four normed division algebras
Alex J. Feingold, Axel Kleinschmidt, Hermann Nicolai
We study the Weyl groups of hyperbolic Kac-Moody algebras of `over-extended' type and ranks 3, 4, 6 and 10, which are intimately linked with the four normed division algebras K=R,C…