@unpublished{63569,
  abstract     = {{Let $G$ be a totally disconnected locally compact (tdlc) group. The contraction group $\mathrm{con}(g)$ of an element $g\in G$ is the set of all $h\in G$ such that $g^n h g^{-n} \to 1_G$ as $n \to \infty$. The nub of $g$ can then be characterized as the intersection $\mathrm{nub}(g)$ of the closures of $\mathrm{con}(g)$ and $\mathrm{con}(g^{-1})$.
 Contraction groups and nubs provide important tools in the study of the structure of tdlc groups, as already evidenced in the work of G. Willis. It is known that $\mathrm{nub}(g) = \{1\}$ if and only if $\mathrm{con}(g)$ is closed. In general, contraction groups are not closed and computing the nub is typically a challenging problem.
 Maximal Kac-Moody groups over finite fields form a prominent family of non-discrete compactly generated simple tdlc groups. In this paper we give a complete description of the nub of any element in these groups.}},
  author       = {{Bischof, Sebastian and Marquis, Timothée}},
  title        = {{{Describing the nub in maximal Kac-Moody groups}}},
  year         = {{2025}},
}

@unpublished{63568,
  abstract     = {{In this article we work out the details of flat groups of the automorphism group of locally finite Bruhat-Tits buildings.}},
  author       = {{Bischof, Sebastian}},
  title        = {{{On flat groups in affine buildings}}},
  year         = {{2025}},
}