题目：Role and modalities of criticality in natural systems revisited and re-evaluated

报告人：Ruedi (Rudolf Robert) Stoop教授

时间：2019年10月22日下午14:30

地点：格致楼4022

主持人：Barbara Dietz教授

报告摘要:

In biological neural systems, activity patterns that can be related to the properties of critical states of statistical mechanics have obtained wide attention, mostly as fingerprints of computational optimality. Commonly, in a given system, a single critical state with well-defined critical exponents that correspond to well-known universality classes of statistical physics is expected to occur. Wefirst demonstrate that this expectation is unjustified [1]. Moreover, we present first experimental evidence of transitions between different critical regimes during the development of in vitro neuronal cultures, and show how a model based on fundamental biological arguments only, reproduces these transitions, at maintained interaction topology [2].

Finally, we present evidence that small size neural networks of the size of a cortical (micro)column follow in their development process a universal behavior, i.e., their development is essentially independent of the specifics of the neuronal dynamics and of the underlying network topology.

These results not only question some more dogmas of the current understanding of neuronal systems, they also offer, more generally, a novel perspective towards understanding the behavior of complex interacting many-body systems - like cortical neural networks - via suitably generalized notions of statistical physics. Our results finally suggest that for understanding biological neural networks, the microscopic focus in the description of biological computational units may be dismissed, for a better-suited mesoscopic approach focusing on interacting networks of higher-level physiological modules.

[1] K. Kanders, T. Lorimer, and R. Stoop, CHAOS 27, 047408 (2017)

[2] K. Kanders, H. Lee, N. Hong, Y. Nam, and R. Stoop, Nat. Comm. Phys., accepted (2019)

报告人简介：

Ruedi (Rudolf Robert) Stoop教授，目前为苏黎世大学、苏黎世联邦理工学院和瑞士西北高等专业学院的荣誉退休教授。Stoop教授于1977年在苏黎世大学获得数学学士学位，于1990年获得苏黎世大学、苏黎世联邦理工学院的物理学博士学位。Stoop教授在PRL、Phil. Trans. Roy. Soc.等国际著名期刊上发表了数十篇论文。Stoop教授为诺尔塔期刊编辑委员会会员、约翰内斯堡国际科学计算学院董事会成员、NOLTA IEEE会议外部指导委员会成员、以及NDES会议董事会成员等。