3 papers
math.RA2026
On the structure of approximate rings
Krzysztof Krupiński, Simon Machado
By a [-]approximate subring of a ring we mean an additively symmetric subset such that is covered by finitely many [resp.\ ] additive translates…
math.GR2019
Infinite Approximate Subgroups of Soluble Lie Groups
Simon Machado
We study infinite approximate subgroups of soluble Lie groups. Generalising a theorem of Fried and Goldman we show that approximate subgroups are close, in a sense to be defined, t…
math.GR2018
Approximate Lattices and Meyer Sets in Nilpotent Lie Groups
Simon Machado
We show that uniform approximate lattices in nilpotent Lie groups are subsets of model sets. This extends a theorem due to Yves Meyer about quasicrystals in Euclidean spaces. To do…