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In 1640's, Blaise Pascal discovered a remarkable property of a hexagon inscribed in a conic - Pascal Theorem, which gave birth of the projective geometry. In this paper, a new geometric invariant of algebraic curves is discovered by a…

Algebraic Geometry · Mathematics 2015-03-19 Zhongxuan Luo

This article presents a clear proof of the Riemann Mapping Theorem via Riemann's method, uncompromised by any appeals to topological intuition.

Complex Variables · Mathematics 2016-12-14 Robert E. Greene , Kang-Tae Kim

The goal of this paper is to give a purely geometric proof of a theorem by Branko Gr\"unbaum concerning configuration of triangles coming from the classical Napoleon's theorem in planar Euclidean geometry.

Metric Geometry · Mathematics 2010-05-12 Nikolay Dimitrov

Let $X$ be a metric space. Recently in~[1] it was considered a new type of mappings $T\colon X\to X$ which can be characterized as mappings contracting perimeters of triangles. These mappings are defined by the condition based on the…

General Topology · Mathematics 2025-02-28 Christian Bey , Evgeniy Petrov , Ruslan Salimov

We prove Dirichlet's theorem for polynomial rings: Let F be a pseudo algebraically closed field. Then for all relatively prime polynomials a(X), b(X)\in F[X] and for every sufficiently large positive integer n there exist infinitely many…

Number Theory · Mathematics 2009-07-16 L. Bary-Soroker

Tubal scalars are usual vectors, and tubal matrices are matrices with every element being a tubal scalar. Such a matrix is often recognized as a third-order tensor. The product between tubal scalars, tubal vectors, and tubal matrices can be…

Spectral Theory · Mathematics 2021-07-28 Yuning Yang , Junwei Zhang

Three circles define each of the Brocard points of a triangle. If one adds the three circles through a pair of vertices and the orthocentre one has nine circles. It is described how each of the nine centres of these circles lies at the…

Metric Geometry · Mathematics 2010-07-08 Christopher J Bradley

We give a complete proof of Thurston's Orbifold Theorem for very good 3-orbifolds of cyclic type. An orbifold is said to be very good when it has a finite cover which is a manifold. A 3-orbifold is of cyclic type if the singular set is a…

Geometric Topology · Mathematics 2007-05-23 M. Boileau , J. Porti

With the usual definitions for the entropy and the temperature associated with the apparent horizon, we show that the unified first law on the apparent horizon is equivalent to the Friedmann equation for the scalar--tensor theory with…

General Relativity and Quantum Cosmology · Physics 2015-07-31 Yumei Huang , Yungui Gong , Dicong Liang , Zhu Yi

In geometry, Monge's theorem states that for any three nonoverlapping circles of distinct radii in the two dimensional analytical plane equipped with the Euclidean metric, none of which is completely inside one of the others, the…

Metric Geometry · Mathematics 2021-04-12 Temel Ermiş , Özcan Gelişgen

As a first application of a very old theorem, known as Herschel's theorem, we provide direct elementary proofs of several explicit expressions for some numbers and polynomials that are known in combinatorics. The second application deals…

Number Theory · Mathematics 2012-05-08 Lazhar Fekih-Ahmed

We use Weierstrass Point Theory and Frobenius orders to prove the uniqueness (up to isomorphism) of some optimal curves.

alg-geom · Mathematics 2008-02-03 Rainer Fuhrmann , Fernando Torres

The topological Tverberg theorem claims that for any continuous map of the (q-1)(d+1)-simplex to R^d there are q disjoint faces such that their images have a non-empty intersection. This has been proved for affine maps, and if $q$ is a…

Combinatorics · Mathematics 2008-02-25 Stephan Hell

We prove a conjecture of Hutchings and Lee relating the Seiberg-Witten invariants of a closed 3-manifold X with b_1 > 0 to an invariant that `counts' gradient flow lines--including closed orbits--of a circle-valued Morse function on the…

Differential Geometry · Mathematics 2014-11-11 Thomas Mark

We shed new light on Heisenberg's uncertainty principle in the sense of Beurling, by offering an essentially different proof which permits us to weaken the assumptions substantially, and examples show that the result is sharp. The proof…

Functional Analysis · Mathematics 2013-11-11 Haakan Hedenmalm

The problem of finding perfect Euler cuboids or proving their non-existence is an old unsolved problem in mathematics. The third cuboid conjecture is the last of the three propositions suggested as intermediate stages in proving the…

Number Theory · Mathematics 2012-03-13 Ruslan Sharipov

The famous Haken-Kneser-Milnor theorem states that every 3-manifold can be expressed in a unique way as a connected sum of prime 3-manifolds. The analogous statement for 3-orbifolds has been part of the folklore for several years, and it…

Geometric Topology · Mathematics 2015-06-26 Carlo Petronio

Many of the strengthenings and extensions of the topological Tverberg theorem can be derived with surprising ease directly from the original theorem: For this we introduce a proof technique that combines a concept of "Tverberg unavoidable…

Combinatorics · Mathematics 2017-12-12 Pavle V. M. Blagojević , Florian Frick , Günter M. Ziegler

We push further the classical proof of Weil upper bound for the number of rational points of an absolutely irreducible smooth projective curve $X$ over a finite field in term of euclidean relationships between the Neron Severi classes in…

Number Theory · Mathematics 2014-09-09 Emmanuel Hallouin , Marc Perret

The Three Gap Theorem states that there are at most three distinct lengths of gaps if one places $n$ points on a circle, at angles of $z, 2z, 3z, \ldots nz$ from the starting point. The theorem was first proven in 1958 by S\'os and many…

Dynamical Systems · Mathematics 2019-02-05 Christian Weiß