activity
20082022
most citedUpper bounds for packings of spheres of several radii

43 citations · 238 across the 16 of their papers we have counts for

collaborators

16 papers

math.CO2022

A recursive theta body for hypergraphs

Davi Castro-Silva, Fernando Mário de Oliveira Filho, Lucas Slot +1

The theta body of a graph, introduced by Grötschel, Lovász, and Schrijver in 1986, is a tractable relaxation of the independent-set polytope derived from the Lovász theta number. I…

math.CO2021★ 1 cited

A recursive Lovász theta number for simplex-avoiding sets

Davi Castro-Silva, Fernando Mário de Oliveira Filho, Lucas Slot +1

We recursively extend the Lovász theta number to geometric hypergraphs on the unit sphere and on Euclidean space, obtaining an upper bound for the independence ratio of these hyper…

math.OC2018★ 13 cited

-point semidefinite programming bounds for equiangular lines

David de Laat, Fabrício Caluza Machado, Fernando Mário de Oliveira Filho +1

We give a hierarchy of -point bounds extending the Delsarte-Goethals-Seidel linear programming -point bound and the Bachoc-Vallentin semidefinite programming -point bound…

math.MG2018★ 11 cited

Complete positivity and distance-avoiding sets

Evan DeCorte, Fernando Mário de Oliveira Filho, Frank Vallentin

We introduce the cone of completely-positive functions, a subset of the cone of positive-type functions, and use it to fully characterize maximum-density distance-avoiding sets as…

math.OC2016

Improving the semidefinite programming bound for the kissing number by exploiting polynomial symmetry

Fabrício Caluza Machado, Fernando Mário de Oliveira Filho

The kissing number of is the maximum number of pairwise-nonoverlapping unit spheres that can simultaneously touch a central unit sphere. Mittelmann and Vallentin (20…

math.MG2015★ 18 cited

New upper bounds for the density of translative packings of three-dimensional convex bodies with tetrahedral symmetry

Maria Dostert, Cristóbal Guzmán, Fernando Mário de Oliveira Filho +1

In this paper we determine new upper bounds for the maximal density of translative packings of superballs in three dimensions (unit balls for the -norm) and of Platonic and…

math.MG2015★ 10 cited

Better bounds for planar sets avoiding unit distances

Tamás Keleti, Máté Matolcsi, Fernando Mário de Oliveira Filho +1

A -avoiding set is a subset of that does not contain pairs of points at distance . Let denote the maximum fraction of that c…

math.OC2014★ 3 cited

Mathematical optimization for packing problems

Fernando Mário de Oliveira Filho, Frank Vallentin

During the last few years several new results on packing problems were obtained using a blend of tools from semidefinite optimization, polynomial optimization, and harmonic analysi…

math.MG2013★ 8 cited

Computing upper bounds for the packing density of congruent copies of a convex body

Fernando Mário de Oliveira Filho, Frank Vallentin

In this paper we prove a theorem that provides an upper bound for the density of packings of congruent copies of a given convex body in ; this theorem is a generaliza…

math.FA2013★ 15 cited

Spectral bounds for the independence ratio and the chromatic number of an operator

Christine Bachoc, Evan DeCorte, Fernando Mario de Oliveira Filho +1

We define the independence ratio and the chromatic number for bounded, self-adjoint operators on an L^2-space by extending the definitions for the adjacency matrix of finite graphs…

math.MG2012★ 43 cited

Upper bounds for packings of spheres of several radii

David de Laat, Fernando Mario de Oliveira Filho, Frank Vallentin

We give theorems that can be used to upper bound the densities of packings of different spherical caps in the unit sphere and of translates of different convex bodies in Euclidean…

math.OC2010★ 27 cited

Grothendieck inequalities for semidefinite programs with rank constraint

Jop Briet, Fernando Mario de Oliveira Filho, Frank Vallentin

Grothendieck inequalities are fundamental inequalities which are frequently used in many areas of mathematics and computer science. They can be interpreted as upper bounds for the…

math.CO2010★ 5 cited

A quantitative version of Steinhaus' theorem for compact, connected, rank-one symmetric spaces

Fernando Mário de Oliveira Filho, Frank Vallentin

Let , , ... be a sequence of positive numbers that converges to zero. A generalization of Steinhaus' theorem due to Weil implies that, if a subset of a homogeneous Rieman…

math.OC2009★ 25 cited

The positive semidefinite Grothendieck problem with rank constraint

Jop Briet, Fernando Mario de Oliveira Filho, Frank Vallentin

Given a positive integer n and a positive semidefinite matrix A = (A_{ij}) of size m x m, the positive semidefinite Grothendieck problem with rank-n-constraint (SDP_n) is maximize…

math.CO2008★ 32 cited

Fourier analysis, linear programming, and densities of distance avoiding sets in R^n

Fernando Mario de Oliveira Filho, Frank Vallentin

In this paper we derive new upper bounds for the densities of measurable sets in R^n which avoid a finite set of prescribed distances. The new bounds come from the solution of a li…

math.CO2008★ 27 cited

Lower bounds for measurable chromatic numbers

Christine Bachoc, Gabriele Nebe, Fernando Mario de Oliveira Filho +1

The Lovasz theta function provides a lower bound for the chromatic number of finite graphs based on the solution of a semidefinite program. In this paper we generalize it so that i…