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Related papers: An effective estimate on Betti numbers

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This paper gives a sharp upper bound for the Betti numbers of a finitely generated multigraded $R$-module, where $R=\Bbbk [x_{1},...,x_{m}]$ is the polynomial ring over a field $\Bbbk$ in $m$ variables. The bound is given in terms of the…

Commutative Algebra · Mathematics 2007-05-23 Amanda Beecher

In this paper we develop a new technique to compute the Betti table of a monomial ideal. We present a prototype implementation of the resulting algorithm and we perform numerical experiments suggesting a very promising efficiency. On the…

Commutative Algebra · Mathematics 2015-07-29 Maria-Laura Torrente , Matteo Varbaro

We prove a priori estimates for constant Chern scalar curvature metrics on a compact complex manifold conditional on an upper bound on the entropy, extending a recent result by Chen-Cheng in the K\"ahler setting.

Differential Geometry · Mathematics 2020-07-07 Xi Sisi Shen

In this article, we extend the compactness theorems proved by Sprouse and Hwang-Lee to a weighted manifold under the assumption that the weighted Ricci curvature is bounded below in terms of its weight function. With the help of the…

Differential Geometry · Mathematics 2022-02-16 Taku Ito

We prove that the second Betti number of a compact Riemannian manifold vanishes under certain Ricci curved restriction.

Differential Geometry · Mathematics 2016-10-31 Jianming Wan

This article is a fundamental study in computable analysis. In the framework of Type-2 effectivity, TTE, we investigate computability aspects on finite and infinite products of effective topological spaces. For obtaining uniform results we…

Logic in Computer Science · Computer Science 2015-07-01 Robert Rettinger , Klaus Weihrauch

We give upper bounds for volume of sublevel sets of real polynomials. Our method is to combine a version of global Lojasiewicz inequality with some well known estimate on volume of tubes around real algebraic sets. Some applications to…

Complex Variables · Mathematics 2018-04-18 Nguyen Quang Dieu , Dau Hoang Hung , Tien Son Pham , Hoang Thieu Anh

We obtain estimates for the nonlinear variational capacity of annuli in weighted R^n and in metric spaces. We introduce four different (pointwise) exponent sets, show that they all play fundamental roles for capacity estimates, and also…

Analysis of PDEs · Mathematics 2017-08-25 Anders Björn , Jana Björn , Juha Lehrbäck

We derive a formula for the energy of a path in the moduli space of a compact $G_2$-manifold with vanishing first Betti number for the volume-normalised $L^2$-metric. This allows us to give simple sufficient conditions for a path of…

Differential Geometry · Mathematics 2025-07-22 Thibault Langlais

We investigate the geometry of word metrics on fundamental groups of manifolds associated with the generating sets consisting of elements represented by closed geodesics. We ask whether the diameter of such a metric is finite or infinite.…

Differential Geometry · Mathematics 2021-06-28 Bastien Karlhofer , Jarek Kędra , Michał Marcinkowski , Alexander Trost

A compact real analytic Riemannian manifold M admits a canonical complexification with plurisubharmonic exhaustion function satisfying the homogeneous complex Monge-Ampere equation, called a Grauert tube. From the point of view of complex…

Complex Variables · Mathematics 2007-05-23 D. Burns , R. Hind

To every real analytic Riemannian manifold M there is associated a complex structure on a neighborhood of the zero section in the real tangent bundle of M. This structure can be uniquely specified in several ways, and is referred to as a…

Complex Variables · Mathematics 2007-05-23 R. Aguilar , D. M. Burns

We establish sharp estimates for the $p$-capacity of metric rings with unrelated radii in metric measure spaces equipped with a doubling measure and supporting a Poincar\'e inequality. These estimates play an essential role in the study of…

Metric Geometry · Mathematics 2013-04-23 Nicola Garofalo , Niko Marola

We prove that for a finite set of points $X$ in the projective $n$-space over any field, the Betti number $\beta_{n,n+1}$ of the coordinate ring of $X$ is non-zero if and only if $X$ lies on the union of two planes whose sum of dimension is…

Commutative Algebra · Mathematics 2024-11-12 Hailong Dao , Ben Lund , Sreehari Suresh-Babu

We use the polynomial partitioning method of Guth to prove weighted Fourier restriction estimates in $\Bbb R^3$ with exponents $p$ that range between $3$ and $3.25$, depending on the weight. As a corollary to our main theorem, we obtain new…

Classical Analysis and ODEs · Mathematics 2017-06-07 Bassam Shayya

We obtain strong upper bounds for the Betti numbers of compact complex-hyperbolic manifolds. We use the unitary holonomy to improve the results given by the most direct application of the techniques of [DS17]. We also provide effective…

Differential Geometry · Mathematics 2025-05-15 Luca F. Di Cerbo , Mark Stern

We prove that the Betti numbers of simplicial complexes of bounded vertex degrees are testable in constant time.

Combinatorics · Mathematics 2009-07-31 Gabor Elek

The asymptotic behavior of graded Betti numbers of powers of homogeneous ideals in a polynomial ring over a field has recently been reviewed. We extend quasi polynomial behavior of graded Betti numbers of powers of homogenous ideals to…

Commutative Algebra · Mathematics 2018-02-13 Kamran Lamei , Siamak Yassemi

In this paper, we show how to construct examples of closed manifolds with explicitly computed irrational, even transcendental L2 Betti numbers, defined via the universal covering. We show that every non-negative real number shows up as an…

K-Theory and Homology · Mathematics 2017-05-17 Mikaël Pichot , Thomas Schick , Andrzej Zuk

The computation of the numerical index of a Banach space is an intriguing problem, even in case of two-dimensional real polyhedral Banach spaces. In this article we present a general method to estimate the numerical index of any…

Functional Analysis · Mathematics 2024-08-13 Debmalya Sain , Kallol Paul , Pintu Bhunia , Santanu Bag