New Trends in Onedimensional Dynamics, celebrating the 70th birthday of Welington de Melo

IMPA, Rio de Janeiro, November 14 – 18, 2016 








Conference Dinner

On November 17th at 19:30h there will be a conference dinner to be held at Rubaiyat, a steak house located 15 minutes from IMPA.
The price for participants is R$150.00 (around US$45) and the payment is to be made at the Secretariat desk, in front of Ricardo Mañé Auditorium.
Included in this price are an entrance, a main course (meat, fish and pasta), dessert and free drinks: water, soft drinks, beer and the famous Brazilian caipirinha.

Program at a glance


Cello Concert

On November 14th, after the Conference Opening, we´ll have a cello concert permormed by Duo Santoro.
Don´t miss it!

Daily Program

Daily Program

Organizing and Scientific Committee

Scientific Committee:

Artur Ávila (IMPA)

Carlos Gustavo T. De A. Moreira (IMPA)

Alejandro Kocsard (Federal University Fluminense)

Maria José Pacifico (Federal University of Rio de Janeiro)

Organizing Committee:

Maria José Pacifico (Federal University of Rio de Janeiro)

Pablo Guarino (Federal University Fluminense)

Invited Speakers

Alberto A. Pinto (Porto)
One dimensional chaotic attractors

Artur Avila (IMPA)

Björn Winckler (Stony Brook)
Topology determines geometry?

Carlos Siqueira (Imperial College)
Quasi-conformal deformations of solenoidal Julia sets and conformal IFS

Charles Tresser (APERIO)
Some questions and a few results on the boundary of topological entropy

Daniel Smania (ICMC)
Multimodal renormalization with bounded combinatorics

Davoud Cheraghi (Imperial College)
On a conjecture of Marmi, Moussa, and Yoccoz on the sizes of Siegel disks

Edson de Faria (USP)
Quasi-symmetric rigidity of multi-critical circle maps

Edson Vargas (USP)
Invariant measure for critical covering maps of the circle

Eleonora Catsigeras (Universidad de la Republica)
Stochastic perturbations of piecewise continuous maps

Ian Melbourne (University of Warwick)
The Lorenz attractor is exponentially mixing

Jorge Sotomayor (IME – USP)
Recurrent Curvature Lines on Euclidean Surfaces

José Vieitez (Facultad de Ingenieria y Agrimesura)
Lyapunov exponents for expansive homeomorphisms and expansive set valued maps

Konstantin Khanin (Toronto)
On typical irrational rotation numbers for circle maps with singularities

Liviana Palmisano (Bristol)
Foliations of Rigidity Classes

Luna Lomonaco (USP)
Mating quadratic maps with the modular group

Marco Lenci (Università di Bologna)
Uniformly expanding Markov maps of the real line: exactness and infinite mixing

Marco Martens (Stony Brook)
Renormalization and Symmetry

Mikhail Lyubich (Stony Brook)
Pacman Renormalization and scaling of the Mandelbrot set at Siegel points

Michael Yampolsky (Toronto)
New results on renormalization and rigidity of analytic critical circle maps

Patrice Le Calvez (Institut de Mathématiques de Jussieu)
Orbit forcing theory for surface homeomorphisms and applications

Pedro Salomão (USP)
Some periodic motions in Reeb dynamics which imply positive topological entropy

Peter Hazard (USP)
Renormalisation of Henon-like mappings of bounded type

Raluca Tanase (State University of New York at Stony Brook)
Julia sets and discrete group actions

Raúl Ures (Universidad de la República)
Ergodicity and Partial Hyperbolicity on Unit Tangent Bundles of Surfaces

Remus Radu (State University of New York at Stony Brook)
Hedgehogs in higher dimensions and their applications

Sebastian van Strien (Imperial College)
Welington de Melo’s work from surface to one-dimensional dynamics

Sheldon Newhouse (Michigan State University)
A generalization of a linearization theorem of Philip Hartman

Steven Smale (Toyota Tech Inst at Chicago)
Perspectives on the pitchfork bifurcation


Registration Fees (due upon arrival)

Category Fee
Students (Master and Ph.D) R$ 80.00
Professors and Researchers (in Brazil) R$ 200.00
Professors and Researchers (Outside of Brazil) US$ 100.00

Poster Session

Parabolic phenomena in C2
Arcelino Lobato (Instituto de Matemática e Estatística da USP)

Measurable dynamics of a generalized Arnol’d family
Arlane Vieira (Universidade Federal do Maranhão)

Amenable graphs and their spectral radius
Elaine Ferreira Rocha (Universidade Federal da Bahia)

Quasisymmetric rigidity of multicritical circle maps
Gabriela Estevez (USP)

Sequential Gibbs Measures and Factor Maps
Giovane Ferreira (Universidade Federal do Maranhão)

Specification of the S. Ulam’s theorem on the topological conjugation of one-dimensional maps
Makar Plakhotnyk (USP)

Uma desigualdade de Ancona para operadores
Sara Ruth Pires Bispo (Universidade Federal da Bahia)

Suggested Accommodations

Rio de Janeiro has a large number of hotels. Lately, for the main congresses, we have been using Hotel Acapulco, Everest Rio Hotel, Everest Park Hotel, Hotel Debret, Hotel Vermont, among others. To take advantage of IMPA´s special rate, please contact Ms. Michele Leite at MMX Eventos – – phone: + 55 21 2210-1732 or visit their homepage at:

For other type of accommodation like hostels and bed and breakfast, we suggest the following:

Pouso Verde Bed & Breakfast (very close to IMPA and strongly recommended)
Rua Caminhoá, 14 – Jardim Botânico
Tel: + 55 21 2529-2942 , + 55 21 99971-0511



Meiai Hostel:
R. Guilhermina Guinle, 127 – Botafogo
Tel: 55(21) 3495-4481


Pousada Girassol
Travessa Angrense, 25 A – Copacabana (entre Santa Clara e Raimundo Correa)
Tel: 55(21)2256-6951 / Fax: 55(21) 2286-5652


Lagoa Guest House
Rua do Humaitá, 392 – Humaitá
Tel: 55(21) 3518-9000


Che Lagarto Ipanema
Rua Paul Redfern 48 – Ipanema
Tel: 55(21) 2512-8076

Leblon Spot (associado à Hostelling International)
Rua Dias Ferreira, 626 – Leblon
Tel: 55(21) 2137-0090

Please check availability and prices directly with them


Hotels and Flats – Rio de Janeiro




Conference Venue

IMPA is located in the South Zone of Rio de Janeiro, near the Tijuca Forest and the Botanical Gardens, 20 minutes from major hotels of Leblon and Ipanema. You can find our address and some practical information about how to get to the institution below.


Estrada Dona Castorina, 110
Jardim Botânico
Zip Code 22460-320
Rio de Janeiro, RJ – Brazil

Phone number: (55 21) 2529-5000
Fax: (55 21) 2512-4115


How to get to IMPA:

From the airport

On leaving the airport we suggest that you take a taxi. There are several companies that have booths located inside the airport facilities, on the way out. A ride to South Zone costs around R$120 to R$150 and takes about 50 minutes. There are also special buses leaving from Terminals 1 and 2, whose routes you can find here.


There are three bus lines running near the Institute:

  • 409 – Saens Peña – Horto (via Lapa)
  • 416 – Saens Peña – Jardim Botânico (Horto) (via Túnel Rebouças)

You can check which buses line is the best for you by clicking here.

The passenger must pay as they enter, using the front door to get on the bus and the rear door to get off the bus. The bus fare is R$ 3,80 and the maximum change given is for a R$ 20,00 bill.

Should you prefer to use a taxi, we suggest the following companies:

MAP of the area

Visa Information

The Brazilian visa system operates under a strict reciprocity policy. That means that all citizens from countries which require visas from Brazilians will have to obtain visas to attend the conference. Beware that to attend a scientific conference in Brazil a tourist visa suffices. Source: Consulate General of Brazil

Foreign participants should get in touch with the nearest Brazilian Consulate (click on the map) to find out whether a visa is required.
Here you find the list of nationalities that are exempt from this requirement, see also the official Ministry of Tourism page, that includes the whole of the European Union and Mercosur. Those who do need visa should note that a tourist visa suffices for the conference attendance; for more information about Brazil, visit the official Brazilian Institute of Tourism website.

In case you need an invitation letter, please contact us:

List of Registered Participants