Advanced Studies Institute in Analysis on Fractal Spaces & Dynamical Systems

Date: August 4-13, 2023
Venue: Urgench State University (Uzbekistan)
Contact: Zair Ibragimov (California State University, Fullerton)
E-mail: zibragimov@fullerton.edu

Key Lecturer: Mario Bonk

University of California

Los Angeles

Mario Bonk

Overview

A Thurston map is a branched covering map on a topological 2-sphere for which the forward orbit of each critical point under iteration is finite. Each such map gives rise to a fractal geometry on its underlying 2-sphere. The study of these maps links diverse area of mathematics such as dynamical systems, classical conformal analysis, Teichmüller theory, and analysis on metric spaces. In my lectures I will give an introduction to this circle of ideas.

Topics

  • Branched coverings and Thurston maps
  • Thurston’s characterization of postcritically-finite rational maps
  • Visual metrics of expanding Thurston maps 
  • Basic notions of quasiconformal geometry
  • The visual sphere of an expanding Thurston map

 

Key Lecturer: Mikhail Lyubich

State University of New York

Stony Brook

Mikhail Lyubich

Overview

Holomorphic Dynamics is a theory of iteration of rational endomorphisms of the Riemann sphere. This theory was founded in the early 20th century in the classical work of Fatou and Julia and has become a central theme in Dynamics in the past fourty years. Methods and ideas of the classical geometric function theory, hyperbolic geometry, and ergodic theory have
found a beautiful interplay in this area.

Topics

  • Classical Fatou-Julia Dichotomy
  • Sullivan's No Wandering Domains Theorem
  • Structural Stability and lambda-lemma
  • Basic structure of the Mandelbrot set
  • Distribution of preimages and periodic points

Invited Lecturers

Sergey Merenkov

Sergiy Merenkov

City College of New York and CUNY Graduate Center

Title: Geometry and dynamics versus regularity for manifold automorphisms.

Abstract: I plan to discuss how regularity of automorphisms of manifolds influences the geometry and dynamics of their minimal sets and vice versa. A particular attention will be given to smooth and quasiconformal homeomorphisms of n-tori, n>=2, and hyperbolic surfaces. The results to be presented are higher dimensional versions of Denjoy's theorem on topological conjugacy for circle diffeomorphisms. 

Pekka Pankka

Pekka Pankka

University of Helsinki, Finland

Title: From quasiregular mappings to quasiregular curves.

Abstract: Quasiregular mappings are a non-injective quasiconformal mappings and they may be viewed as a higher dimensional generalization of holomorphic mappings. I will first discuss some of the recent results in their global theory. Then I will discuss a new class of mappings generalizing both quasiregular mappings and holomorphic curves, called quasiregular curves.

Dzmitry Dudko

Dzmitry Dudko

State University of New York at Stony Brook

Title:  From Denjoy's Theorem to the Renormalization Theory.

Abstract: Renormalization is a powerful tool for understanding dynamical systems on various scales. We will introduce some of the renormalization ideas, often illustrating them on pictures. In the first talk, we  will review Denjoy's Theorem on rotation number and then proceed to finer renormalization questions involving circle maps. In the second talk, we will discuss the period-doubling renormalization of real quadratic polynomials and make an analogy between the associated adding machine attractor and circle maps.

Sabyasachi MukherjeeSabya Mukherjee

Tata Institute of Fundamental  Research, India

Title: Fractals arising from antiholomorphic maps and reflection groups.

Abstract:  We will explicate topological and geometric structures of fractal sets arising from iterations of antiholomorphic rational maps (complex conjugates of rational maps of the Riemann sphere) and Kleinian reflection groups. We will also explain, mostly at the level of examples, how these conformal dynamical systems can be combined to manufacture richer systems with unusual dynamical and complex-analytic properties.

Zhiqiang LiZhiqiang Li

Peking University, China

Title: Introduction to ergodic optimization and its connection to fractal spaces

Abstract:  Ergodic optimization is a young area in ergodic theory, closely related to thermodynamic formalism. It studies a special class of measures, called maximizing measures, and has close connections to various other parts of mathematics. In this mini-course, we will give an introduction to ergodic optimization and discuss some recent developments in connection to fractal spaces arising from complex dynamics.

 Program Schedule

 

August 4, 2023 

 

11:00 – 11:30                       Registration

11:30 – 12:00                      Opening Remarks

                                      Zair Ibragimov - California State University, Fullerton

                                      Bakhrom Abdullaev - Rector, Urgench State University

                                      Misha Lyubich - State University of New York, Stony Brook

                                      Mario Bonk - University of California, Los Angeles

 

12:00 – 13:00                     Lunch

13:00 – 14:30                     Rest (Faculty Housing)

14:30 – 15:20                     Speaker: Mario Bonk

                                     Title: Branched coverings and Thurston maps, I

15:30 – 16:20                     Speaker: Mario Bonk

                                     Title: Branched coverings and Thurston maps, I

16:30 – 17:00                    Coffee Break

17:00 – 17:50                    Speaker: Sergiy Merenkov

                                    Title: Geometry and dynamics vs. regularity for manifold automorphisms, I

18:00 – 18:50                    Speaker: Sergiy Merenkov

                                    Title: Geometry and dynamics vs. regularity for manifold automorphisms, II

19:30 – 21:30                    Dinner

 

August 5, 2023 

 

10:00 – 10:50                    Speaker: Mario Bonk         

                                               Title: Thurston’s characterization of postcritically-finite rational maps

11:00 – 11:50                      Speaker: Mario Bonk

                                     Title: Visual metrics of expanding Thurston maps

12:00 – 12:30                     Coffee Break

12:30 – 13:20                      Speaker: Zhiqiang Li

                                      Title: Introduction to ergodic optimization and connection to fractal spaces, I

13:30 – 14:30                       Lunch

14:30 – 17:00                       Rest (Faculty Housing)

17:00 – 17:50                       Speaker: Pekka Pankka

                                       Title: From quasiregular mappings to quasiregular curves, I

18:00 – 18:50                       Speaker: Pekka Pankka

                                        Title: From quasiregular mappings to quasiregular curves, II

19:30 – 21:30                       Dinner

 

August 6, 2023 (Khorazm Mamun Academy)

 

08:00 – 08:50                      Speaker: Mario Bonk

                                        Title: Basic notions of quasiconformal geometry

09:00 – 09:50                      Speaker: Mario Bonk

                                        Title: The visual sphere of an expanding Thurston map

10:00 – 10:30                       Tour of Khorezm Mamun Academy

10:30 – 11:20                        Speaker: Zhiqiang Li

                                        Title: Introduction to ergodic optimization and connection to fractal spaces II

12:00 – 14:00                       Lunch (Ichan Kala)

15:00 – 19:00                       Guided Tour of Ichan Kala

19:30 – 22:00                       Banquet for Mario (Ichan Kala)

 

August 7, 2023 

 

10:00 – 10:50                        Speaker: Misha Lyubich

                                        Title: Classical Fatou-Julia Dichotomy, I

11:00 – 11:50                         Speaker: Misha Lyubich

                                         Title: Classical Fatou-Julia Dichotomy, II

12:00 – 12:30                        Coffee Break

12:30 – 13:30                          Recitation Session (Moderator: Zhiqiang Li)

13:30 – 14:30                         Lunch

14:30 – 17:00                         Rest (Faculty Housing)

17:00 – 17:50                         Speaker: Dzmitry Dudko

                                         Title: From Denjoy’s Theorem to the Renormalization Theory, I

18:00 – 18:50                         Speaker: Dzmitry Dudko

                                          Title: From Denjoy’s Theorem to the Renormalization Theory curves, II

19:30 – 21:30                          Dinner

August 8, 2023 

 

10:00 – 10:50                        Speaker: Misha Lyubich

                                        Title: Classical Fatou-Julia Dichotomy, III

11:00 – 11:50                         Speaker: Misha Lyubich

                                         Title: Structural Stability and lambda-lemma

12:00 – 12:30                        Coffee Break

12:30 – 13:30                          Recitation Session (Moderators: Zhiqiang Li and Timothy Alland)

13:30 – 14:30                         Lunch

14:30 – 17:00                         Rest (Faculty Housing)

17:00 – 17:50                         Speaker: Sabyasachi Mukherjee

                                         Title: Fractals arizing from antiholomorphic maps and reflection groups, I

18:00 – 18:50                         Speaker: Sabyasachi Mukherjee

                                          Title: Fractals arizing from antiholomorphic maps and reflection groups, II

19:30 – 21:30                          Dinner

August 9, 2023 

 

08:00 – 13:00                        Trip to Ayaz Kala

13:30 – 14:30                         Lunch

14:30 – 16:00                         Rest (Faculty Housing)

16:00 – 17:00                          Recitation Session (Moderator: Timothy Alland)

17:00 – 17:50                         Speaker: Misha Lyubich

                                                    Title: Basic structure of the Mandelbrot set

18:00 – 18:50                         Speaker: Misha Lyubich

                                                    Title: Distribution of preimages and periodic points

19:30 – 22:00                         Banquet for Misha (Urgench)

 

August 10-13, 2023 

               Trips to Bukhara (August 10-11), Samarkand (August 11-12) and Tashkent (August 12-13)

List of Student Participants

 

  • Alberto Acevedo (The University of Arizona) 
  • Nurali Akramov (National University of Uzbekistan) 
  • Klara Allaberganova (Novosibirsk State University) 
  • Timothy Alland (State University of New York at Stony Brook) 
  • Yuke An (Peking University) 
  • Reginald Anderson (Kansas State University) 
  • Jinru Bai (Peking University) 
  • Sardor Bekchanov (Urgench State University) 
  • Katherine Booth (Georgia Institute of Technology) 
  • Rasiel Chishti (Pennsylvania State University) 
  • Carmen Day (California State University,  Channel Islands) 
  • Abigail D'Ovidio Long (University of Nebraska-Lincoln) 
  • Kutlimurat Erkinboyev (Urgench State University) 
  • Davis Funk (West Virginia University) 
  • Nicholas Hanson (University of Illinois, Chicago) 
  • Qiangdu He (Peking University) 
  • Yinying Huang (Peking University) 
  • Okhunjon Ismoilov (Romanovski Institute of Mathematics) 
  • Mukhiddin Ismoilov (National University of Uzbekistan) 
  • Ashley Jubb (California State University, Fullerton) 
  • Maxliyo Kadirova (Novosibirsk State University) 
  • Xursandbek Kamolov (Urgench State University) 
  • Xiaoran Li (Peking University) 
  • Mohammed Mannan (New York University) 
  • Alan Mitchell (University of California, Irvine) 
  • Aditya Mohan (University of California, Santa Barbara) 
  • Eden Nava-Martinez (California State University, Long Beach) 
  • Salvador Ochoa Zavalza (University of California, Davis) 
  • Karen Padgett (California State University, Fullerton) 
  • Ruicen Qiu (Peking University) 
  • Tanner Reese (The University of Arizona) 
  • Cynthia Rivera Sánchez (University of Puerto Rico) 
  • Rafael Saavedra (Harvard University) 
  • Xianghui Shi (Peking University) 
  • G‘ulomjon Sotliqov (Urgench State University) 
  • Yiqing Sun (Peking University) 
  • William Wood (University of California, Irvine) 
  • Ranfeng Yu (Peking University) 
  • Hanyun Zheng (Peking University) 
  • Qu Zhengbo (Peking University)