# Category Archives: Mathematics

## Progress checking Zarankiewicz’s conjecture on the brick factory problem

A previous post presented the fascinating history of the brick factory problem, which wonders about the smallest possible number of rail crossings when connecting kilns and storage yards, which is mathematically modeled by the crossing number of the complete […]

## The fascinating history of the brick factory problem

The crossing number of a graph, defined as the minimum number of edge crossings arising when the graph is drawn in the plane, turns out to be a mathematical concept with a fascinating history.

Lowell Beineke and Robin Wilson […]

## Every convex polyhedron can be refolded to a different one

Choose your favorite convex polyhedron in the space. Make sure it is convex, since the current post is restricted to that kind of polyhedra

An unfolding of your convex polyhedron is a development of its surface to a single […]

## How much should we ... produce?

Decision making in areas such as production planning, distribution and grid management, logistics or financial portfolio management is usually based on mathematical models, mathematical optimization themselves.

Let us assume that we have to take a decision of how many units […]

## Advances on an Erdős problem on convex boundaries

Among his around 1525 papers, Paul Erdős considered On sets of distances of n points as his most important contribution to discrete geometry. There, he stated:

On the boundary of every convex body, there exists a point P […]

## Always look on the light side of graphs

Consider a set of distinct points in the plane, no three of them on the same line. Draw straight-line segments joining pairs of those points. This is called a geometric graph and here we are going to focus on […]

## Epistemology in the courts. Or, Sherlock Holmes is dead, long live to Thomas Bayes.

Strange as it may sound to many people, the fact is that some of the most interesting work on epistemology that is being currently done in Spain is carried out at the headquarters of the Spanish gendarmerie (the well known […]

## The Holy Spirit game, or a sip of conclave economics

Imagine the following situation: about 100 people have to choose one of them for an important position; they have different preferences about who must be chosen, some may have a stronger or lighter interest in being elected, but, and this […]