Results 11 to 20 of about 145 (122)

A practical algorithm for weighted k‐hulls

open access: yesComputer Graphics Forum, EarlyView.
Abstract The convex hull is a central concept in computational geometry, geometry processing, and generally for summarizing sampled data. Its descriptive power suffers significantly in the presence of noise. The k‐hull, also known as the k‐depth contour in statistics, is the intersection of all half‐spaces that contain all but k data points, i.e. it is
N. Look, H. Meyer, M. Alexa
wiley   +1 more source

Effective length‐projection bounds for hyperbolic 3‐manifolds diffeomorphic to S×R$S\times \mathbb {R}$

open access: yesJournal of Topology, Volume 19, Issue 3, September 2026.
Abstract We give a formula with explicit constants relating the subsurface projection dY(ν−,ν+)$d_Y(\nu ^-,\nu ^+)$ of the end invariants ν−,ν+$\nu ^-,\nu ^+$ of a hyperbolic 3‐manifold Q$Q$ diffeomorphic to S×R$S\times \mathbb {R}$ and the length of the geodesic representative in Q$Q$ of the multicurve ∂Y$\partial Y$.
Gabriele Viaggi
wiley   +1 more source

Lower bounds for cube‐ideal set‐systems

open access: yesProceedings of the London Mathematical Society, Volume 133, Issue 2, August 2026.
Abstract A set‐system S⊆{0,1}n$S\subseteq \lbrace 0,1\rbrace ^n$ is cube‐ideal if its convex hull can be described by capacity and generalized set covering inequalities. In this paper, we use combinatorics, convex geometry, and polyhedral theory to give exponential lower bounds on the size of cube‐ideal set‐systems, and linear lower bounds on their ...
Ahmad Abdi   +3 more
wiley   +1 more source

Identifiability of points and rigidity of hypergraphs under algebraic constraints

open access: yesJournal of the London Mathematical Society, Volume 114, Issue 1, July 2026.
Abstract The identifiability problem arises naturally in a number of contexts in mathematics and computer science. Specific instances include local or global rigidity of graphs and unique completability of partially‐filled tensors subject to rank conditions.
James Cruickshank   +3 more
wiley   +1 more source

Circle packings, renormalizations, and subdivision rules

open access: yesProceedings of the London Mathematical Society, Volume 132, Issue 4, April 2026.
Abstract In this paper, we use iterations of skinning maps on Teichmüller spaces to study circle packings and develop a renormalization theory for circle packings whose nerves satisfy certain subdivision rules. We characterize when the skinning map has bounded image.
Yusheng Luo, Yongquan Zhang
wiley   +1 more source

The systole of random hyperbolic 3‐manifolds

open access: yesJournal of the London Mathematical Society, Volume 113, Issue 3, March 2026.
Abstract We study the systole of a model of random hyperbolic 3‐manifolds introduced in Petri and Raimbault [Comment. Math. Helv. 97 (2022), no. 4, 729–768], answering a question posed in that same article. These are compact manifolds with boundary constructed by randomly gluing truncated tetrahedra along their faces.
Anna Roig‐Sanchis
wiley   +1 more source

A tropical approach to rigidity: Counting realisations of frameworks

open access: yesJournal 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

Rigidity of anti‐de Sitter (2+1)‐spacetimes with convex boundary near the Fuchsian locus

open access: yesJournal of the London Mathematical Society, Volume 113, Issue 2, February 2026.
Abstract We prove that globally hyperbolic compact anti‐de Sitter (2+1)‐spacetimes with a strictly convex spacelike boundary that is either smooth or polyhedral and whose holonomy is close to Fuchsian are determined by the induced metric on the boundary.
Roman Prosanov, Jean‐Marc Schlenker
wiley   +1 more source

Toric amplitudes and universal adjoints

open access: yesJournal 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

Canonical forms of oriented matroids

open access: yesBulletin of the London Mathematical Society, Volume 58, Issue 1, January 2026.
Abstract Positive geometries are semialgebraic sets equipped with a canonical differential form whose residues mirror the boundary structure of the geometry. Every full‐dimensional projective polytope is a positive geometry. Motivated by the canonical forms of polytopes, we construct a canonical form for any tope of an oriented matroid inside the Orlik–
Christopher Eur, Thomas Lam
wiley   +1 more source

Home - About - Disclaimer - Privacy