Category Archives: Article
Colors: It’s not just about Wavelengths!
Colours... What are they really? Are there the same for all of us? And for other animals? How does color addition or subtraction work? How do they work on computers? And on printers? The mysterious (but not dark) world of colors is actually very colourful!
P versus NP: A Crucial Open Problem
P=NP is probably today's most crucial open problem. Not only is it a very theoretical question in computer science and mathematics, but it also has major implications to real world. Its resolution could revolutionize the world. This article gives the definition and major results of P=NP.
From Divide and Conquer to Parallelization
Divide and conquer is a extremely powerful concept that is being used a lot in computer science, and that can also be applied in real life. We present its application to sorting algorithms. Then we'll talk about a major fundamental open mathematical problem, called P=NC.
Duality in Linear Programming
Duality in linear programming yields plenty of amazing results that help understand and improve algorithms of resolution. This article shows the construction of the dual and its interpretation, as well as major results. In particular, matching of primal and dual bases will be dealt, before presenting the issue of degeneracy and its dual interpretation.
Primal and Dual Simplex Methods
The simplex method is one of the major algorithm of the 20th century, as it enables the resolution of linear problems with millions of variables. An intuitive approach is given. But that's not all. We present an important variant called the dual simplex. Finally, we'll explain its main default, that is, when facing degeneracy.
Dual Variable Stabilization
Simplex methods face issues in case of degeneracy. The dual variable stabilization is a very recent state-of-the-art way to deal with degeneracy. An intuitive understanding is given in this article.
The coach’s dilemma.
Intro Crisis. Most analysts believe that it’s a financial crisis. Others say it’s a crisis of the economic system in general. Others speak of political crisis. I’ll tell you what its real cause is: it’s a crisis of egoism. And I’m going to prove it in a mathematical way. We’ll show it through a football […]
Marriage Assignment Problem and Variants
Marriage problems consist in matching boys and girls. They are a very interesting class of problems that include assignment problems, which have a very large range of applications. Additional results have been found for variants which include the introduction of boys and girls' preferences, and cases where people cannot be categorized into two groups.
Optimization by Linear Programming
Operations Research deals with optimizing industrial systems. Those systems can be very complex and their modeling may require the use of hundreds, thousands or even millions of variables. Optimizing over millions of variables may seem impossible, but it can be done if the optimization problem has a linear structure. Learn more on this linear structure and optimization solutions!
From Britain’s coast to Julia set: an introduction to fractals
Introduction I could have started this article by showing you beautiful examples of fractals, found in nature or invented by mathematicians, in two or three dimensions, constructed deterministically or not. But I won’t. In fact, you wouldn’t need to read this article to find such examples. I’d rather start by telling you a story. It […]
Mechanism Design and the Revelation Principle
Whenever you need to make a group of people interact, you are designing a mechanism. If you want to achieve a good interaction, you need to make sure your mechanism is well designed. In this article, I'll show you main features of mechanisms through various examples. I'll also talk about a great mathematical tool for mechanism design: the revelation principle.
Regulation of Electricity Markets
Electricity markets are not like any markets. In particular, they cannot be liberalized without regulation. In the article, I list the reasons why this market is specific and I conclude by giving you important features of a good regulation.
Fair Division and Cake-Cutting
Cutting a cake to satisfy everyone is no piece of cake! In the article, we focus on classical definitions of fair divisions. I'll criticize those definitions and conclude by extrapolating them to fairness in society.