Publications related to Physics of Complex Systems Laboratory

Thermally activated flow in models of amorphous solids

Matthieu Wyart, Thomas Willem Jan de Geus, Wencheng Ji, Marko Popovic

Amorphous solids yield at a critical value Sigma(c) of the imposed stress Sigma through a dynamical phase transition. While sharp in athermal systems, the presence of thermal fluctuations leads to the rounding of the transition and thermally activated flow ...

AMER PHYSICAL SOC2021

Inferring the flow properties of epithelial tissues from their geometry

Matthieu Wyart, Marko Popovic, Valentin Camille Druelle

Amorphous materials exhibit complex material properties with strongly nonlinear behaviors. Below a yield stress they behave as plastic solids, while they start to yield above a critical stress sigma(c). A key quantity controlling plasticity which is, howev ...

2021

Comparing dynamics: deep neural networks versus glassy systems

Matthieu Wyart, Mario Geiger, Marco Baity-Jesi, Stefano Spigler, Levent Dogus Sagun

We analyze numerically the training dynamics of deep neural networks (DNN) by using methods developed in statistical physics of glassy systems. The two main issues we address are (1) the complexity of the loss landscape and of the dynamics within it, and ( ...

IOP PUBLISHING LTD2019

Comparing Dynamics: Deep Neural Networks versus Glassy Systems

Rainer Wesche, Marco Baity-Jesi, Mario Geiger, Stefano Spigler, Levent Dogus Sagun

We analyze numerically the training dynamics of deep neural networks (DNN) by using methods developed in statistical physics of glassy systems. The two main issues we address are the complexity of the loss-landscape and of the dynamics within it, and to wh ...

2018

Numerical simulation of mechanical deformation of semi-solid material using a level-set based finite element method

Roland Logé

In this work, a level-set based finite element method was used to numerically evaluate the mechanical behavior in a small deformation range of semi-solid materials with different microstructure configurations. For this purpose, a finite element model of th ...

Institute of Physics2017

Scaling for hard-sphere colloidal glasses near jamming

Eric DeGiuli

Hard-sphere colloids are model systems in which to study the glass transition and universal properties of amorphous solids. Using covariance matrix analysis to determine the vibrational modes, we experimentally measure here the scaling behavior of the dens ...

IOP Publishing - EPL Association2016

Fluid and glassy phases of vibrated granular matter studied with a torsion oscillator

Patrick Mayor

Granular matter submitted to external perturbations exhibits various behaviors depending on the vibration intensity: when strongly vibrated, the granular system has a fluid aspect, whereas under low intensity perturbations, it is in a quasi-solid phase. In ...

EPFL2005