Noticias en español
A spectral proof of Szemerédi’s regularity lemma.
Resumen: In this talk I will present the spectral proof of the regularity lemma due to Frieze and Kannan in the version popularized by Tao.
Read MoreAggregating opinions — do we need (Kolmogorov) complexity?
Abstract: Imagine a group of people that need each day to make some collective decision (for the entire group), choosing one of two options A and B. Some people prefer A, some prefer B, and others are OK with any of the two options. (The next day the preferences may change arbitrarily, and a new group choice is made.) The group management needs to choose A or B, in both cases making some people unhappy. This cannot be avoided completely (if someone wants A and someone else wants B, one of them will be unhappy), so the goal is more modest: each person should not be unhappy too many times....
Read MoreAlgebraic intersections in translation surface.
RESUMEN: The purpose of this talk is to discuss the maximal possible (algebraic) intersection of closed curves of a given length on translation surfaces. One way to quantify this is to define the so-called “interaction strength” of the surface. The (moduli) space of translation surfaces comes with a natural SL(2,ℝ)-action and we are interested in understanding the behaviour of the interaction stength under this action. After having introduced translation surfaces and the SL(2,ℝ)-action, we will give a few geometric ideas and focus on the case of the Golden L for which we can...
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