EPFLとカレル大学の科学者が、磁性不純物を含む金やソーシャルメディア上で拡散する意見など、複雑な無秩序系の動的で平衡状態から外れた特性を分析する新しい方法を開発した。 Scientists at EPFL and Charles University have developed a new method to analyze the dynamical, out-of-equilibrium properties of complex disordered systems, such as gold with magnetic impurities or opinions spreading on social media.
2023-08-25 スイス連邦工科大学ローザンヌ校(EPFL)
◆EPFLの科学者チームは、無秩序なシステム内の変化を理解する新しいアプローチである「バックトラッキング・ダイナミカル・キャビティ・メソッド（BDCM）」を開発しました。この方法は終了点からシステムの進化を逆向きに追跡するもので、システムの動的特性に貴重な洞察を提供します。
◆この方法を用いて、磁石のランダム配置などのシステムを研究し、急速な冷却時のエネルギー変化や異なる配置からのパターン形成などを理解しました。このアプローチは社会ネットワークや脳の動作など、多くの複雑な相互作用システムのダイナミクスの研究に適用できる可能性があります。
＜関連情報＞
- https://actu.epfl.ch/news/unraveling-complex-systems-the-backtracking-method/
- https://journals.aps.org/prx/abstract/10.1103/PhysRevX.13.031021
バックトラック動的空洞法 Backtracking Dynamical Cavity Method
Freya Behrens, Barbora Hudcová, and Lenka Zdeborová
Physical Review X Published 21 August 2023
DOI:https://doi.org/10.1103/PhysRevX.13.031021
ABSTRACT
The cavity method is one of the cornerstones of the statistical physics of disordered systems such as spin glasses and other complex systems. It is able to analytically and asymptotically exactly describe the equilibrium properties of a broad range of models. Exact solutions for dynamical, out-of-equilibrium properties of disordered systems are traditionally much harder to obtain. Even very basic questions such as the limiting energy of a fast quench are so far open. The dynamical cavity method partly fills this gap by considering short trajectories and leveraging the static cavity method. However, being limited to a couple of steps forward from the initialization, it typically does not capture dynamical properties related to attractors of the dynamics. We introduce the backtracking dynamical cavity method that instead of analyzing the trajectory forward from initialization, it analyzes the trajectories that are found by tracking them backward from attractors. We illustrate that this rather elementary twist on the dynamical cavity method leads to new insight into some of the very basic questions about the dynamics of complex disordered systems. This method is as versatile as the cavity method itself, and we hence anticipate that our paper will open many avenues for future research of dynamical, out-of-equilibrium properties in complex systems.
