English
Related papers

Related papers: The 4-Intersection Unprojection Format

200 papers

We construct some new deformation families of four-dimensional Fano manifolds of index $1$ in some known classes of Gorenstein formats. These families have explicit descriptions in terms of equations, defining their image under the…

Algebraic Geometry · Mathematics 2021-07-09 Muhammad Imran Qureshi

This paper describes the relationship between the first non-vanishing Milnor invariants of a classical link and the intersection invariant of a twisted Whitney tower. This is a certain 2-complex in the 4-ball, built from immersed disks…

Geometric Topology · Mathematics 2015-03-18 James Conant , Rob Schneiderman , Peter Teichner

An obstruction theory for representing homotopy classes of surfaces in 4-manifolds by immersions with pairwise disjoint images is developed, using the theory of non-repeating Whitney towers. The accompanying higher-order intersection…

Geometric Topology · Mathematics 2015-01-19 Rob Schneiderman , Peter Teichner

We begin the study of the notion of diameter of an ideal I of a polynomial ring S over a field, an invariant measuring the distance between the minimal primes of I. We provide large classes of Hirsch ideals, i.e. ideals with diameter not…

Commutative Algebra · Mathematics 2017-05-10 Michela Di Marca , Matteo Varbaro

Gay and Kirby introduced the notion of a trisection of a smooth 4-manifold, which is a decomposition of the 4-manifold into three elementary pieces. Rubinstein and Tillmann later extended this idea to construct multisections of…

Geometric Topology · Mathematics 2019-04-05 Peter Lambert-Cole , Maggie Miller

In recent work of T. Cassidy and the author, a notion of complete intersection was defined for (non-commutative) regular skew polynomial rings, defining it using both algebraic and geometric tools, where the commutative definition is a…

Rings and Algebras · Mathematics 2015-03-04 Michaela Vancliff

Universal Photometric Stereo is a promising approach for recovering surface normals without strict lighting assumptions. However, it struggles when multi-illumination cues are unreliable, such as under biased lighting or in shadows or…

Computer Vision and Pattern Recognition · Computer Science 2025-11-19 King-Man Tam , Satoshi Ikehata , Yuta Asano , Zhaoyi An , Rei Kawakami

We demonstrate the existence of numerous non-spin 4-manifolds for which the smooth Nielsen realization problem fails; namely, there exist finite subgroups of their mapping class groups that cannot be realized by any group of…

Geometric Topology · Mathematics 2023-10-13 Mihail Arabadji , R. Inanc Baykur

This paper contains new results on two classical topics in fractal geometry: projections, and intersections with affine planes. To keep the notation of the abstract simple, we restrict the discussion to the planar cases of our theorems. Our…

Classical Analysis and ODEs · Mathematics 2016-07-27 Pertti Mattila , Tuomas Orponen

The twisted torsion of a 3-manifold is well-known to be zero whenever the corresponding twisted Alexander module is non-torsion. Under mild extra assumptions we introduce a new twisted torsion invariant which is always non-zero. We show how…

Geometric Topology · Mathematics 2010-09-30 Jae Choon Cha , Stefan Friedl

The projection onto the intersection of sets generally does not allow for a closed form even when the individual projection operators have explicit descriptions. In this work, we systematically analyze the projection onto the intersection…

Optimization and Control · Mathematics 2018-04-16 Heinz H. Bauschke , Minh N. Bui , Xianfu Wang

This paper studies algebraic residual intersections in rings with Serre's condition \( S_{s} \). It demonstrates that residual intersections admit free approaches i.e. perfect subideal with the same radical. This fact leads to determining a…

Commutative Algebra · Mathematics 2025-02-13 S. Hamid Hassanzadeh

Gay and Kirby introduced trisections which describe any closed oriented smooth 4-manifold $X$ as a union of three four-dimensional handlebodies. A trisection is encoded in a diagram, namely three collections of curves in a closed oriented…

Geometric Topology · Mathematics 2021-06-21 Vincent Florens , Delphine Moussard

We introduce twisted matrix factorizations for quantum complete intersections of codimension two. For such an algebra, we show that in a given dimension, almost all the indecomposable modules with bounded minimal projective resolutions…

K-Theory and Homology · Mathematics 2017-10-23 Petter Andreas Bergh , Karin Erdmann

Consider the polynomial ring $R_n = k[x_1,...,x_n]$, where $k$ is a field. Let $m = (x_1,...,x_n)$ and $I$ be an $m$-primary monomial ideal in $R$. We consider the problem of determining whether such ideals are in the Gorenstein liasion…

Commutative Algebra · Mathematics 2026-05-19 Benjamin Mudrak

We present layered ray intersections (LaRI), a new method for unseen geometry reasoning from a single image. Unlike conventional depth estimation that is limited to the visible surface, LaRI models multiple surfaces intersected by the…

Computer Vision and Pattern Recognition · Computer Science 2025-04-28 Rui Li , Biao Zhang , Zhenyu Li , Federico Tombari , Peter Wonka

For even dimensional smooth complete intersections, of dimension at least 4, of two quadric hypersurfaces in a projective space, we study the genus zero Gromov-Witten invariants by the monodromy group of its whole family. We compute the…

Algebraic Geometry · Mathematics 2022-04-12 Xiaowen Hu

This paper provides a topological method to construct all simply-connected, spin, smooth $6$-manifolds with torsion-free homology using simply-connected, smooth $4$-manifolds as building blocks. We explicitly determine the invariants that…

Geometric Topology · Mathematics 2013-06-06 Ahmet Beyaz

We show that main results of rational trigonometry (as developed by NJ Wildberger, "Divine Proportions", 2005) can be succinctly expressed using projective geometric algebra (PGA). In fact, the PGA representation exhibits distinct…

General Mathematics · Mathematics 2020-06-12 Charles Gunn

Active stereo vision is important in reconstructing objects without obvious textures. However, it is still very challenging to extract and match the projected patterns from two camera views automatically and robustly. In this paper, we…

Computer Vision and Pattern Recognition · Computer Science 2020-04-01 Yongcan Shuang , Zhenzhou Wang