ELFT HÍRADÓ

[Kormányos Andor <andor.kormanyos AT ttk.elte.hu>]

ELTE TTK Fizikai Intézet / ELTE Institute of Physics


ORTVAY KOLLOKVIUM / ORTVAY COLLOQUIUM
(https://physics.elte.hu/ortvayseminar)


Thursday, 6th April  2023, 15:00h.

Pócza Jenő Classroom,  Physics Building 1.71

Pázmány Péter sétány 1/A, 1117 Budapest.


Ulrike  Feudel

Carl von Ossietzky University, Oldenburg

 Tipping phenomena and resilience in complex systems

Many systems in nature are characterized by the coexistence of different 
stable states for a given set of environmental parameters and external 
forcing. Examples for such behavior can be found in different fields of 
science ranging from mechanical or chemical systems to ecosystem and climate 
dynamics. As a consequence of the coexistence of a multitude of stable 
states, the final state of the system depends strongly on the initial 
condition.  Perturbations, applied to those natural systems can lead to a 
critical transition from one stable state to another. Such critical 
transitions are called tipping phenomena in climate science, regime shifts in 
ecology or phase transitions in physics. Such critical transitions can happen 
in various ways: (1) due to bifurcations, i.e. changes in the dynamics when 
external forcing or parameters are varied extremely slow (2) due to 
fluctuations which are always inevitable in natural systems, (3) due to 
rate-induced transitions, i.e. when external forcing changes on 
characteristic time scale comparable to the time scale of the considered 
dynamical system and (4) due to shocks or extreme events. We discuss these 
critical transitions and their characteristics and illustrate them with 
examples from mechanical and natural systems. Moreover, we discuss the 
concept of resilience, which has been originally introduced by C.S. Holling 
in ecology, and reformulated in terms of dynamical systems theory.


The seminar can also be followed via Microsoft Teams:

https://teams.microsoft.com/l/meetup-join/19%3a175464fd39534a6c84d06c831ff5dd09%40thread.tacv2/1680246218906?context=%7b%22Tid%22%3a%22b366dbcd-4fc3-4451-82d2-e239564302c3%22%2c%22Oid%22%3a%22560bcc66-85b7-4700-9055-41903a3659ca%22%7d


Andor Kormányos
coordinator