Papers › A cyclotomic family of thin hypergeometric monodromy groups in Sp₄(ℝ)

A cyclotomic family of thin hypergeometric monodromy groups in Sp₄(ℝ)

17 Jun 2021arXiv:2106.09181links table onlyarchive 2025-07-28

Simion Filip, Charles Fougeron

The archive published only this paper's code-link row. Authors, date and abstract are from arXiv's metadata (CC0), read from the Kaggle arXiv metadata snapshot of 2026-09-12 where its title matched the archive's; the title is the archive's.

We exhibit an infinite family of discrete subgroups of Sp₄(ℝ) which have a number of remarkable properties. Our results are established by showing that each group plays ping-pong on an appropriate set of cones. The groups arise as the monodromy of hypergeometric differential equations with parameters (N-32N,N-12N, N+12N, N+32N) at infinity and maximal unipotent monodromy at zero, for any integer N≥4. Additionally, we relate the cones used for ping-pong in ℝ⁴ with crooked surfaces, which we then use to exhibit domains of discontinuity for the monodromy groups in the Lagrangian Grassmannian.

PaperPDFCode

Code

Repository list and official/mentioned flags are the archive's, frozen 2025-07-28. Reachability, where shown, is from one Syntology probe window (2026-09-16 to 2026-09-18); repositories not probed show nothing. GitHub stars are not tracked.

Code Syntology ran Syntology

Not run by Syntology. Nothing on this page verifies that the listed code works.

Results from the paper archive 2025-07-28

No leaderboard rows for this paper in the archive.

Report a problem or propose a change · a person checks every report against the paper or source before anything changes; decisions are listed on /corrections