English

Constructing bounded orbits of special types on homogeneous spaces

Dynamical Systems 2026-02-03 v2

Abstract

Let X=G/ΓX = G/\Gamma be a quotient of a real Lie group by a non-uniform lattice. Consider a one-parameter subgroup FF of GG that is Ad\operatorname{Ad}-diagonalizable over C\mathbb{C} and whose action on (X,mX)(X,m_X) is mixing. In this dynamical system we study the set of points xXx \in X with a precompact orbit, written as E(F,)E(F,\infty), which is known to be a dense subset of XX of full Hausdorff dimension. We prove that E(F,)E(F,\infty) is indecomposable in the following sense: given any yE(F,)y \in E(F,\infty), the set of xE(F,)x \in E(F,\infty) for which yF+xy \in \overline{F_+x}, where F+F_+ denotes the positive ray in FF, is uncountable and dense in E(F,)E(F,\infty). When the dimension of the neutral subgroup of GG with respect to FF is 11 we demonstrate, for any ε>0\varepsilon>0, the existence of many points xXx \in X whose orbit closure F+xX\overline{F_+x} \subset X is compact and has Hausdorff dimension at least dimXε\dim X - \varepsilon.

Keywords

Cite

@article{arxiv.2511.16095,
  title  = {Constructing bounded orbits of special types on homogeneous spaces},
  author = {Manfred Einsiedler and Dmitry Kleinbock and Anurag Rao},
  journal= {arXiv preprint arXiv:2511.16095},
  year   = {2026}
}

Comments

18 pages; several misprints were corrected and the presentation was improved

R2 v1 2026-07-01T07:46:42.761Z