Program
2021.2 August - December
17, 19, 24 & 26 August : Jaqueline Siqueira
2pm-3:30pm (Rio de Janeiro) Universidade Federal de Rio de Janeiro
Rio de Janeiro, Brazil
A Brief Introduction to Ergodic Theory
Abstract: Describing the behaviour of the orbits of a dynamical system can be a challenging task, especially for systems that have a complicated topological and geometrical structure. A very useful way to obtain features of such systems is via invariant probability measures. For instance, by Birkhoff’s Ergodic Theorem, almost every initial condition in each ergodic component of an invariant measure has the same statistical distribution in space. Moreover, in recent years, Ergodic Theory has proven to be a very effective tool in solving problems in other fields such as Topology, Differential Geometry and Number Theory (e.g. the celebrated Green-Tao Theorem).
The purpose of this mini course is to introduce some of the fundamental features of Ergodic Theory, such as invariant and ergodic probability measures, the Poincaré Recurrence Theorem and Birkhoff’s Ergodic Theorem, thus providing a starting point in this great field.
Program
Lecture 1: The course will begin with a quick review of Measure Theory, providing the needed requisites.
I will then introduce the concept of invariant measure and derive certain dynamical properties via the Poincaré Recurrence Theorem.
Lecture 2: In this lecture we will show that under general conditions one can guarantee the existence of invariant measures. We will then discuss a few examples of dynamical systems with invariant measures.
Lecture 3: In this lecture we introduce the concept of ergodicity and discuss examples of ergodic systems.
Lecture 4: In the last lecture we will formulate Birkhoff’s Ergodic Theorem and present a few nice consequences of this powerful result.
21, 23, 28 & 30 September : Timoteo Carletti
2pm-3:30pm (Rio de Janeiro's time) Université de Namur,
& Center for Complex Systems, Belgium
Complex Networks & Dynamical Systems
19, 21, 26 & 28 October : Mark Levi
2pm-3:30pm (Rio de Janeiro's time) Pennsylvania State University, USA
Topics in Hamiltonian Mechanics
30 November , 2, 7 & 9 December : Tomas Alarcon
2pm-3:30pm (Rio de Janeiro's time) Centro de Ricerca Matematica - CRM
Bellaterra (Barcelona), Catalunya, Spain.
An introduction to stochastic modelling in Mathematical Biology
Summary: In this course, I will review the application of applied stochastic methods with an emphasis on those subjects which are relevant to the application of the theory to problems in Mathematical Biology
Lecture 1. General Introduction: motivation (noise-induced phenomena), general definitions and basic concepts
Lecture 2. Markov processes: The Chapman-Kolmogorov equation, The Master Equation, and Asymptotic methods and rare events
Lecture 3. Numerical methods: The Gillespie algorithm and the $\tau$-leap method
Lecture 4. Multiple scales in stochastic systems: a brief introduction
2021.1 April - June
12 & 14 April : Otávio Marçal Leandro Gomide
2pm-3:30pm (Rio de Janeiro) Universidade Federal de Goiás
Goiânia, Brazil
Uma breve Introdução aos Sistemas Dinâmicos
Resumo: Sistemas dinâmicos são frequentemente utilizados para entender como um fenômeno se comporta com a evolução do tempo, e por esse motivo constituem uma ferramenta essencial da modelagem matemática que possui aplicações em diversas áreas como a Física, Biologia, Engenharia, dentre outras. O principal objetivo deste curso é introduzir as definições básicas de sistemas dinâmicos e ilustrar tais conceitos através de alguns exemplos. Abordaremos os casos de dinâmica em tempo discreto e em tempo contínuo.
Programa:
Sistemas Dinâmicos Discretos: Definições e Exemplos;
A dinâmica de uma rotação no círculo;
Fluxos e Equações Diferenciais: Definições e Exemplos
Sistemas lineares planares.
Referências:
1) D. K. Arrowsmith, C. M. Place. An Introduction to Dynamical Systems. Cambridge University Press. 1990.
2) J. Sotomayor. Lições de Equações Diferenciais Ordinárias. IMPA, 1979.
3) M. Kot. Elements of Mathematical Ecology. Cambridge University Press, 2001.
20, 22, 27 & 29 April : Hildeberto Cabral
2pm-3pm (Rio de Janeiro) Universidade Federal de Pernambuco
Recife, Brazil
Estabilidade de Sistemas Hamiltonianos Lineares (Stability of Linear Hamiltonian Systems)
Resumo : O problema de estabilidade de sistemas Hamiltonianos, se não for a situação de dois graus de liberdade em que o teorema de Arnold se aplica, é um problema em geral difícil de ser tratado. Neste caso estuda-se a estabilidade do sistema linearizado na vizinhança do equilíbrio e este é o objetivo do curso proposto.
Programa :
Teoria básica de sistemas Hamiltonianos
Forma normal de matrizes Hamiltonianas
Estabilidade de sistemas Hamiltonianos lineares periódicos
Teoria de Krein-Gelfand-Lidskii sobre estabilidade forte de sistemas lineares periódicos
Problema da ressonância paramétrica, curvas fronteiras das regiões de estabilidade/instabilidade
2pm-3pm (Rio de Janeiro) Universitat Politècnica de Catalunya
7pm-8pm (Barcelona) Barcelona, Catalunya, Spain
Introduction to Mathematical Neuroscience
Abstract : The study of the brain has attracted the attention of scientists from differ- ent disciplines; amongst them, mathematics have sought tools and mathematical models for the study of this body. Mathematical neuroscience aims at under- standing the fundamental mechanisms responsible for neuronal activity patterns observed experimentally. Modelling is important to interpret experimental data, test hypothesis, make predictions, and suggest new experiments.
The goal of this course is to introduce some basic mathematical models de- scribing firing dynamics in neuronal systems, both at the single cell and network level, including the widely studied Hodgkin-Huxley and Wilson-Cowan models. We will analyse this models using tools from dynamical systems theory that will be reviewed alongside (bifurcation analysis, singular perturbation theory, averaging, ..). Finally, I will present some examples of applications of neuronal modelling to some describe cognitive tasks such as decision making.
Timetable
Lesson 1 (1h) Membrane biophysics and the Hodgkin-Huxley model.
Lesson 2 (1h) Excitability and action potentials. Phase-plane analysis.
From resting state to oscillations (bifurcation analysis).Lesson 3 (1h) Firing rate models for neuronal populations. Wilson-Cowan equations.
Lesson 4 (1h) Applications to cognitive tasks (decision making, perception).
References
[1] B.G. Ermentrout and D.H. Terman. Mathematical foundations of neuro- science. New York : Springer, 2010.
[2] J. Rinzel and G. Huguet. Nonlinear Dynamics of Neuronal Excitability, Oscillations, and Coincidence Detection.
Communications on Pure and Applied Mathematics, 66(9):1464-1494, 2013.
[3] S. H. Strogatz. Nonlinear Dynamics and Chaos. With Applications to Physics, Biology, Chemistry, and Engineering.
Studies in Nonlinearity, Perseus Books, 1994.
8, 10, 15 & 17 June : Angel Jorba
2pm-3pm (Rio de Janeiro) Universitat de Barcelona
7pm-8pm (Barcelona) Barcelona, Catalunya, Spain