Research

Research topics

In my way of understanding life there are random cycles that rule our behavior, they help us to learn, take decisions and solve problems. For instance, every morning, month, season, year... we restart some of our activities and start taking decisions about what we want and what we have to do. Every other summer day we like to go out with friends to have beer and enjoy of the company and the nice weather, we do not know what is gone happen next time, but it is rewarding to do it. Based in previous experiences we build routines and forge our character. Each of our decisions is based in previous experiences that help us to get the best of what we do. In this way, we build some probability rules that help us decide the next movement, get the best of the moment and reduce our risk of failure. Not all random patterns appear as time moves on, of course, look at a Brassica oleracea and you will know of what I mean.  Random cycles and patterns are present in many phenomena in life. 


I think that is one of the reasons why I became a reasercher specialized in stochastic processes and you will often find renewal theory, the theory of excursions from a set, and Markov processes theory as some of my favourite tools. Among other, these are powerful tools that can be  applied in almost any area of stochastic modelling, as for instance to build fluctuation theory of real valued Lévy processes and of Markov additive processes


Self-similarity is at the basis of theory of fractals and chaos, and it rules the behavior of various fundamental stochastic processes that appear as scaling limits of other stochastic processes. Examples of these are stable processes and self-similar Markov processes. Self-similar Markov processes are related to Lévy and Markov additive processes through the so-called Lamperti's transform.  


Local times are random clocks that are useful to describe the amount of time spent in particular spots, in particular they are helpful to understand the lengths of the above mentioned random cycles. We can study the dependence of the time spent in two or more neighboring spots, this leads to the study of local times as stochastic processes in the space variable.  They are closely related to branching processes and to various of the topics mentionned above.


The topics marked in bold letters and the questions that appear related to them are the core of my research, their rich mathematical structure connects them to many area of mathematics, and are useful in modelling various phenomena from nature.  


Go to the research page to know more about the output of my research


Research articles

Books

Books edited