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Related papers: Generalized convex sets and shadows problem

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Several results about the union-closed sets conjecture are presented.

Combinatorics · Mathematics 2017-06-21 Yining Hu

In this work, starting from a spherically symmetric scale--dependent black hole, a rotating solution is obtained by following the Newman--Janis algorithm without complexification. Besides studying the horizon, the static conditions and…

General Relativity and Quantum Cosmology · Physics 2020-04-01 Ernesto Contreras , Ángel Rincón , Grigoris Panotopoulos , Pedro Bargueño , Benjamin Koch

We investigate the shadow properties of a wide class of spacetimes arising from different parameter regimes of the generalized Hayward metric, characterized by two independent parameters $(\sigma, \kappa)$ (Phys. Rev. D 106, 044028). This…

General Relativity and Quantum Cosmology · Physics 2025-08-18 Suvikranth Gera , Saurabh Kumar , Poulami Dutta Roy , Sayan Chakrabarti

Assuming a lower bound on the dimension, we prove a long standing conjecture concerning the classification of global solutions of the obstacle problem with unbounded coincidence sets.

Analysis of PDEs · Mathematics 2022-08-08 Simon Eberle , Henrik Shahgholian , Georg S. Weiss

We show that there are many (compact) convex semi-algebraic sets in euclidean space that do not have a semidefinite representation. This gives a negative answer to a question by Nemirovski, resp. it shows that the Helton-Nie conjecture is…

Optimization and Control · Mathematics 2017-12-05 Claus Scheiderer

After surveying some known properties of compact convex sets in the plane, we give a two rigorous proofs of the general feeling that supporting lines can be slide-turned slowly and continuously. Targeting a wide readership, our treatment is…

Combinatorics · Mathematics 2016-12-06 Gábor Czédli , László L. Stachó

We provide a solution to the problem of simultaneous $diagonalization$ $via$ $congruence$ of a given set of $m$ complex symmetric $n\times n$ matrices $\{A_{1},\ldots,A_{m}\}$, by showing that it can be reduced to a possibly…

Optimization and Control · Mathematics 2021-02-10 Miguel D. Bustamante , Pauline Mellon , M. Victoria Velasco

Shadow removal is an important computer vision task aiming at the detection and successful removal of the shadow produced by an occluded light source and a photo-realistic restoration of the image contents. Decades of re-search produced a…

Computer Vision and Pattern Recognition · Computer Science 2020-10-23 Florin-Alexandru Vasluianu , Andres Romero , Luc Van Gool , Radu Timofte

The aim of this paper is to prove a fixed point theorem on a generalised cone metric spaces for maps satisfying general contractive type conditions.

Classical Analysis and ODEs · Mathematics 2016-10-04 Sudip Kumar Pal , Manojit Maity

The projector onto the Minkowski sum of closed convex sets is generally not equal to the sum of individual projectors. In this work, we provide a complete answer to the question of characterizing the instances where such an equality holds.…

Optimization and Control · Mathematics 2018-09-17 Heinz H. Bauschke , Minh N. Bui , Xianfu Wang

In this paper we generalize the fundamental equation of information to the symmetric cone domain and find general solution under the assumption of continuity of respective functions.

Classical Analysis and ODEs · Mathematics 2017-08-01 Bartosz Kołodziejek

A quadratically constrained quadratic program (QCQP) is an optimization problem in which the objective function is a quadratic function and the feasible region is defined by quadratic constraints. Solving non-convex QCQP to global…

Optimization and Control · Mathematics 2018-12-27 Asteroide Santana , Santanu S. Dey

The magnifications of the images in a strong gravitational lens system are sensitive to small mass clumps in the lens potential; this effect has been used to infer the amount of substructure in galaxy dark matter halos. I study the theory…

Astrophysics · Physics 2009-11-07 Charles R. Keeton

Previous works on black hole shadows have been primarily focused on studying shadows in asymptotically flat and anti-de Sitter space times. In the present work, we find general expressions for asymptotically de Sitter black hole shadow as…

General Relativity and Quantum Cosmology · Physics 2020-07-29 Rittick Roy , Sayan Chakrabarti

The Illumination Problem may be phrased as the problem of covering a convex body in Euclidean $n$-space by a minimum number of translates of its interior. By a probabilistic argument, we show that, arbitrarily close to the Euclidean ball,…

Metric Geometry · Mathematics 2016-02-24 Márton Naszódi

We study smoothness of generalized solutions of nonlocal elliptic problems in plane bounded domains with piecewise smooth boundary. The case where the support of nonlocal terms can intersect the boundary is considered. We announce…

Analysis of PDEs · Mathematics 2014-04-22 Pavel Gurevich

In this paper we invastigate the notion of generalized (I,J) - Luzin set. This notion generalize the standard notion of Luzin set and Sierpinski set. We find set theoretical conditions which imply the existence of generalized (I,J) - Luzin…

Logic · Mathematics 2010-03-04 Robert Ralowski , Szymon Zeberski

The work consists of solutions of metric problems for convex and finite subsets of geodesic spaces.

Metric Geometry · Mathematics 2010-11-30 Evgenii N. Sosov

In the cold dark matter scenario, dark matter halos are assembled hierarchically from smaller subunits. Some of these subunits are disrupted during the merging process, whereas others survive temporarily in the form of subhalos. A…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 E. Zackrisson , T. Riehm

A convex polygon is defined as a sequence (V_0,...,V_{n-1}) of points on a plane such that the union of the edges [V_0,V_1],..., [V_{n-2},V_{n-1}], [V_{n-1},V_0] coincides with the boundary of the convex hull of the set of vertices…

General Mathematics · Mathematics 2007-05-23 Iosif Pinelis