Results 11 to 20 of about 157 (62)
A Miyaoka–Yau inequality for hyperplane arrangements in CPn$\mathbb {CP}^n$
Journal of the London Mathematical Society, Volume 113, Issue 4, April 2026.Abstract Let H$\mathcal {H}$ be a hyperplane arrangement in CPn$\mathbb {CP}^n$. We define a quadratic form Q$Q$ on RH$\mathbb {R}^{\mathcal {H}}$ that is entirely determined by the intersection poset of H$\mathcal {H}$. Using the Bogomolov–Gieseker inequality for parabolic bundles, we show that if a∈RH$\mathbf {a}\in \mathbb {R}^{\mathcal {H}}$ is ...
Martin de Borbon, Dmitri Panov
wiley +1 more source
A tropical approach to rigidity: Counting realisations of frameworks
Journal of the London Mathematical Society, Volume 113, Issue 2, February 2026.Abstract A realisation of a graph in the plane as a bar‐joint framework is rigid if there are finitely many other realisations, up to isometries, with the same edge lengths. Each of these finitely many realisations can be seen as a solution to a system of quadratic equations prescribing the distances between pairs of points.
Oliver Clarke +6 more
wiley +1 more source
Toric amplitudes and universal adjoints
Journal of the London Mathematical Society, Volume 113, Issue 2, February 2026.Abstract A toric amplitude is a rational function associated with a simplicial polyhedral fan. The definition is inspired by scattering amplitudes in particle physics. We prove algebraic properties of such amplitudes and study the geometry of their zero loci. These hypersurfaces play the role of Warren's adjoint via a dual volume interpretation.
Simon Telen
wiley +1 more source
Coxeter's enumeration of Coxeter groups
Journal of the London Mathematical Society, Volume 113, Issue 1, January 2026.Abstract In a short paper that appeared in the Journal of the London Mathematical Society in 1934, H. S. M. Coxeter completed the classification of finite Coxeter groups. In this survey, we describe what Coxeter did in this paper and examine an assortment of topics that illustrate the broad and enduring influence of Coxeter's paper on developments in ...
Bernhard Mühlherr, Richard M. Weiss
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Combination theorems for Wise's power alternative
Journal of the London Mathematical Society, Volume 113, Issue 1, January 2026.Abstract We show that Wise's power alternative is stable under certain group constructions, use this to prove the power alternative for new classes of groups and recover known results from a unified perspective. For groups acting on trees, we introduce a dynamical condition that allows us to deduce the power alternative for the group from the power ...
Mark Hagen +2 more
wiley +1 more source
Chordal Graphs, Even‐Hole‐Free Graphs and Sparse Obstructions to Bounded Treewidth
Journal of Graph Theory, Volume 110, Issue 3, Page 351-365, November 2025.ABSTRACT Even‐hole‐free graphs pose a central challenge in identifying hereditary classes of bounded treewidth. We investigate this matter by presenting and studying the following conjecture: for an integer t ≥ 4 and a graph H, every even‐hole‐free graph of large enough treewidth has an induced subgraph isomorphic to either K t or H, if (and only if) H
Sepehr Hajebi
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The Stanley-Reisner ideal of the rook complex of polyominoes
, 2022 We study the properties of the rook complex $\mathcal{R}$ of a polyomino $\mathcal{P}$ seen as independence complex of a graph $G$, and the associated Stanley--Reisner ideal $I_\mathcal{R}$.
Romeo, Francesco
core
Moments, sums of squares, and tropicalization
Journal of the London Mathematical Society, Volume 112, Issue 4, October 2025.Abstract We use tropicalization to study the duals to cones of nonnegative polynomials and sums of squares on a semialgebraic set S$S$. The truncated cones of moments of measures supported on the set S$S$ are dual to nonnegative polynomials on S$S$, while “pseudomoments” are dual to sums of squares approximations to nonnegative polynomials.
Grigoriy Blekherman +4 more
wiley +1 more source
Geometric lower bounds for generalized ranks [PDF]
, 2014 We revisit a geometric lower bound for Waring rank of polynomials (symmetric rank of symmetric tensors) of Landsberg and Teitler and generalize it to a lower bound for rank with respect to arbitrary varieties, improving the bound given by the "non ...
Teitler, Zach
core
Geometric realizations of the s‐weak order and its lattice quotients
Journal of the London Mathematical Society, Volume 112, Issue 3, September 2025.Abstract For an n$n$‐tuple s${\bm{s}}$ of nonnegative integers, the s${\bm{s}}$‐weak order is a lattice structure on s${\bm{s}}$‐trees, generalizing the weak order on permutations. We first describe the join irreducible elements, the canonical join representations, and the forcing order of the s${\bm{s}}$‐weak order in terms of combinatorial objects ...
Eva Philippe, Vincent Pilaud
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