math.GT daily digest: 3 new submissions for 17 June 2026

The 17 June 2026 arXiv math.GT new listing contains 7 total entries: 1 new submission, 2 cross-lists, and 4 replacements. This issue covers the 3 eligible new/cross-list papers and excludes the 4 replacements. 1

Metadata. Calcut and Du; 14 pages, 13 figures; primary subject math.GT; submitted 15 June 2026 UTC. 2

Main result. The boundaries of all Mazur and Jester 4-manifolds are pairwise nonhomeomorphic, even after reversing orientation. Therefore the corresponding smooth compact contractible 4-manifolds are pairwise nonhomeomorphic. 5

Proof idea. The paper models Mazur's knot exterior in S^1 x S^2 with one regular ideal octahedron by cutting and regluing along a thrice-punctured sphere related to the Whitehead link exterior. Adams' theorem transfers the hyperbolic structure, giving volume 3.66386...; the Jester exterior is built from two copies, giving volume 7.32772.... The boundary 3-manifolds are then read as Dehn fillings. Rigidity, volume monotonicity, and the uniqueness of the shortest filling-core geodesic for long slopes force equal slopes after drilling, while the exceptional fillings are checked separately. 5

Metadata. Kemme, Agyingi, Farrelly, and Barbensi; cross-listed from math.AT with math.GT and q-bio.BM; submitted 15 June 2026 UTC. 3

Main result. The paper reports that knotting leaves a detectable persistent-homology-derived curvature signal. From a curve point cloud, it computes one-dimensional persistent homology, extracts cycle representatives, encodes them as hyperedges, and assigns unweighted undirected Forman-Ricci curvature. 6

Evidence and technique. The protein study covers four knot or slipknot classes, K+3(1), S+3(1), K4(1), and S4(1), compared with unknotted homologs at at least 40% sequence similarity. All four knotted or slipknotted families show significantly lower variance in median Forman-Ricci curvature after FDR correction; three of four show a significant Kolmogorov-Smirnov distributional shift. A synthetic-loop test with Topoly-generated curves at L = 100, 150, ..., 500 finds significant knotted-vs-unknotted separation from L = 200 onward. The proposed mechanism is that entanglement makes persistent cycles overlap more, raising hyperedge degrees and pushing F(e) = 2|e| - D downward. 6

Metadata. Heim and Thomas; 41 pages; cross-listed from math.GR with math.GT; submitted 16 June 2026 UTC. 4

Main result. For a PD^3 group with a nontrivial homogeneous quasimorphism to R and coarsely connected quasikernel, the group is either the fundamental group of a torus or Klein-bottle bundle over S^1, or its quasikernel is coarsely equivalent to H^2; in the second case the group is quasiisometric to a complete Riemannian (R^3, g) and is finitely presented. In the hyperbolic case, the group acts faithfully on S^1 by quasisymmetric homeomorphisms. 7

Proof idea. The authors replace the kernel in Stallings' fibering theorem by the coarse quasikernel of a quasimorphism. A coarse Shapiro lemma connects coarse cohomology of the quasikernel to group cohomology with coarse coinduced coefficients. Novikov homology and a Sikorav-style theorem provide coarse finiteness. Poincare duality then makes the quasikernel a coarse PD^2 space, which is classified by a homological isoperimetric argument as amenable or quasiisometric to H^2. The amenable branch gives the bundle alternative; the H^2 branch is converted into a quasiisometric Riemannian R^3 model using a self-quasiisometry of H^2 and the Douady-Earle extension. 7