Opening address (Hisao Hayakawa, YITP, Kyoto Univ.) Room: K206

Yue Liu "The mechanism of Mpemba effect in overdamped system" 30 min = 23 min talk + 7 min discussion Room: K206

Satoshi Takada "Mpemba effect in a two-dimensional bistable potential" 30 min = 23 min talk + 7 min discussion Room: K206

Frédéric van Wijland (CNRS & Univ. Paris Cité) "Wetting by active particles" (30 min = 23 min talk + 7 min discussion) Room: K206

Michio Otsuki "Hysteresis and marginal stability of cohesive grains" (30 min = 23 min talk + 7 min discussion) Room: K206

Harukuni Ikeda "Scaling theory for critical phenomena in steady shear flow" (30 min = 23 min talk + 7 min discussion) Room: K206

Suravi Pal "Dynamical and mechanical heterogeneities of cancer cells as active deformable particles" 15 min = 12 min talk + 3 min discussion Room: K206

Sucharita Niyogi "Heterogeneous Carrier Transport Across Sublattice Melting in a Minimal Model Superionic Conductor" 15 min = 12 min talk + 3 min discussion Room: K206

Takeshi Kawasaki "What do deep neural networks find in disordered structures of glasses?" 30 min = 23 min talk + 7 min discussion Room: K206

Kuniyasu Saitoh "Active jamming of chiral active Brownian particles confined in a circular geometry" 30 min = 23 min talk + 7 min discussion Room: K206

Kota Noto "Weakly nonlinear analysis using a Hessian matrix with wave-number dependence" 20 min = 15 min talk + 5 min discussion Room: K206

Prabhu Nott (Indian Institute of Science) "The mechanics of disordered granular media in statics and flow: biased random walks to jamming-yielding dynamics" Room: K206 Disordered granular media, such as sand, mineral ores and food grains, exhibit features that are both solid-like and fluid-like. However, their mechanical response differs substantially from elastic solids and viscous fluids, due to the complexity of inter-grain interactions. In the static state, it is known that the stress depends strongly on how the grain assembly is created. In the flowing state, experiments show two contrasting rheological regimes, namely slow (quasistatic) and rapid (inertial) flow, for which the dependence of the stress on the shear rate are very different. We show that a combination of particle dynamics simulations and experiments throw light on the nature of stress transmission in static and flowing granular media, which lead to the development of closure or constitutive relations for the stress. We show that propagation of contact force in a static grain assembly under gravity can be thought of as a biased random walk. This helps us derive a simple closure relation for the macroscopic stress. For grains flowing in the slow flow regime, we show that deformation occurs via recurrent jamming-yielding dynamics, with the stress being elastic in the jammed phases and yielding occurring in short bursts. This findings lead to explanations for the rate independence of the stress and dilatancy, which are distinctive features of slow granular flow.