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Differentiable rendering has received increasing interest for image-based inverse problems. It can benefit traditional optimization-based solutions to inverse problems, but also allows for self-supervision of learning-based approaches for…

Computer Vision and Pattern Recognition · Computer Science 2021-04-02 Linjie Lyu , Marc Habermann , Lingjie Liu , Mallikarjun B R , Ayush Tewari , Christian Theobalt

Shadows encode rich information about scene geometry and illumination, yet existing methods either predict a unified shadow mask or overlook attached shadows entirely. We address this gap by proposing a framework for jointly detecting cast…

Computer Vision and Pattern Recognition · Computer Science 2026-03-20 Shilin Hu , Jingyi Xu , Sagnik Das , Dimitris Samaras , Hieu Le

A theorem of Scott gives an upper bound for the normalized volume of lattice polygons with exactly $i>0$ interior lattice points. We will show that the same bound is true for the normalized volume of lattice polytopes of degree 2 even in…

Combinatorics · Mathematics 2009-01-13 Jaron Treutlein

We present a number of complexity results concerning the problem of counting vertices of an integral polytope defined by a system of linear inequalities. The focus is on polytopes with small integer vertices, particularly 0/1 polytopes and…

Computational Complexity · Computer Science 2022-05-04 Heng Guo , Mark Jerrum

We prove an upper bound of the form $2^{O(d^2 \mathrm{polylog}\,d)}$ on the number of affine (resp. linear) equivalence classes of, by increasing order of generality, 2-level d-polytopes, d-cones and d-configurations. This in particular…

Combinatorics · Mathematics 2018-06-18 Samuel Fiorini , Marco Macchia , Kanstantsin Pashkovich

We define an analogue of the cube and an analogue of the 5-wedge in higher dimensions, each with $2d+2$ vertices and $d^2+2d-3$ edges. We show that these two are the only minimisers of the number of edges, amongst d-polytopes with $2d+2$…

Combinatorics · Mathematics 2020-05-15 Guillermo Pineda-Villavicencio , Julien Ugon , David Yost

In arrangements of pseudocircles (Jordan curves) the weight of a vertex (intersection point) is the number of pseudocircles that contain the vertex in its interior. We give improved upper bounds on the number of vertices of weight <=k in…

Combinatorics · Mathematics 2008-06-13 Ronald Ortner

In their paper, Bounds on the Number of Edges in Hypertrees, G.Y. Katona and P.G.N. Szab\'o introduced a new, natural definition of hypertrees in $k$-uniform hypergraphs and gave lower and upper bounds on the number of edges. They also…

Combinatorics · Mathematics 2017-07-04 Péter G. N. Szabó

Motivated by the problem of bounding the number of rays of plane tropical curves we study the following question: Given $n\in\mathbb{N}$ and a unimodular $2$-simplex $\Delta$ what is the maximal number of vertices a lattice polytope…

Combinatorics · Mathematics 2018-05-28 Jan-Philipp Litza , Christoph Pegel , Kirsten Schmitz

A compact object illuminated by background radiation produces a dark silhouette. The edge of the silhouette or shadow (alternatively, the apparent boundary or the critical curve) is commonly determined by the presence of the photon sphere…

General Relativity and Quantum Cosmology · Physics 2025-09-09 Parth Bambhaniya , Saurabh , Elisabete M. de Gouveia Dal Pino

In this thesis we consider ordered graphs (that is, graphs with a fixed linear ordering on their vertices). We summarize and further investigations on the number of edges an ordered graph may have while avoiding a fixed forbidden ordered…

Discrete Mathematics · Computer Science 2009-07-16 Craig Weidert

The Hirsch Conjecture stated that any $d$-dimensional polytope with n facets has a diameter at most equal to $n - d$. This conjecture was disproved by Santos (A counterexample to the Hirsch Conjecture, Annals of Mathematics, 172(1) 383-412,…

Optimization and Control · Mathematics 2025-04-22 Yaguang Yang

Using the Riemann Hypothesis over finite fields and bounds for the size of spherical codes, we give explicit upper bounds, of polynomial size with respect to the size of the field, for the number of geometric isomorphism classes of…

Number Theory · Mathematics 2013-08-20 Étienne Fouvry , Emmanuel Kowalski , Philippe Michel

Let $P_n$ be an $n$-dimensional regular polytope from one of the three infinite series (regular simplices, regular crosspolytopes, and cubes). Project $P_n$ onto a random, uniformly distributed linear subspace of dimension $d\geq 2$. We…

Probability · Mathematics 2017-04-20 Zakhar Kabluchko , Christoph Thäle

In this paper we provide some exact formulas for the projective dimension and the regularity of edge ideals of vertex-weighted oriented unicyclic graphs. These formulas are in function of the weight of the vertices, the numbers of edges. We…

Commutative Algebra · Mathematics 2023-09-20 Guangjun Zhu , Hong Wang

A kind of fixed-point problem in the area of discrete tomography is proposed and investigated. Our chief concern in this paper is the case of square windows in the plane. Dealing with the arrays which are bounded, of polynomial growth, and…

Combinatorics · Mathematics 2014-04-07 Fumio Hazama

Frank-Wolfe methods are popular for optimization over a polytope. One of the reasons is because they do not need projection onto the polytope but only linear optimization over it. To understand its complexity, Lacoste-Julien and Jaggi…

Data Structures and Algorithms · Computer Science 2020-11-26 Luis Rademacher , Chang Shu

For a polynomial dynamical system, we study the problem of computing the minimal differential equation satisfied by a chosen coordinate (in other words, projecting the system on the coordinate). This problem can be viewed as a special case…

Symbolic Computation · Computer Science 2026-04-17 Yulia Mukhina , Gleb Pogudin

This paper is concerned with the analysis of the randomized subspace iteration for the computation of low-rank approximations. We present three different kinds of bounds. First, we derive both bounds for the canonical angles between the…

Numerical Analysis · Mathematics 2018-11-13 Arvind K. Saibaba

We consider an interesting class of combinatorial symmetries of polytopes which we call \emph{edge-length preserving combinatorial symmetries}. These symmetries not only preserve the combinatorial structure of a polytope but also map each…

Metric Geometry · Mathematics 2020-11-24 Egor Morozov