4th Regular Kakenhi Meeting with Prof. Itamar Procaccia
"Theoretical studies of nonequilibrium phenomena in dissipative-driven systems, 2024"
Date: Mar. 4th, 2024
Hybrid meeting: in-person (K206, YITP, Kyoto Univ.) & online
Registration form for general participants
Tentative time schedulue
| Presentation Time | Speaker |
|---|---|
| 09:30—10:00 | Hisao Hayakawa (YITP, Kyoto Univ., Japan) "Physics of Mpemba effect: quantum and classical anomalous relaxation processes" (abstract) |
| 10:00—10:30 | Satoshi Takada (Tokyo Univ. Agri. & Tech., Japan) "Kinetic theory of moderately dense dry granular particles under a simple shear: steady flows and anomalous relaxation dynamics" (abstract) |
| 10:30—10:50 | break |
| 10:50—11:20 | Yasutaka Iwashita (Kyoto Sangyo Univ., Japan) "Unique motion of self-propelled rod by induced charge electrophoresis" (abstract) |
| 11:20—12:05 | Atsushi Ikeda (Univ. Tokyo, Japan) "A link between anomalous viscous loss and boson peak in soft jammed solids" (abstract) |
| 12:05—13:30 | lunch |
| 13:30—15:00 | Itamar Procaccia (Weizmann Institute of Science, Israel) "Anomalous Elasticity and Emergent Dipole Screening in Amorphous Solids" (abstract)I will review our recent work in which we developed a screening theory for describing the effect of plastic events in amorphous solids on their emergent mechanics. The suggested theory uncovered an anomalous mechanical response of amorphous solids where plastic events collectively induce distributed dipoles that are analogous to dislocations in crystalline solids. Classical elasticity is unable to predict the observed phenomena, and a novel theory needs to be derived and solved. The theory was tested against various srtaining protocols of amorphous solids in two and three dimensions, including frictional and friction-less granular media and numerical models of amorphous glass. I will conclude by interpreting the mechanical response as the formation of non-topological distributed dipoles that have no analogue in the crystalline defects literature. Having in mind that the onset of dipole screening is reminiscent of Kosterlitz-Thouless and Hexatic transitions, the finding of dipole screening in three-dimensions is particularly novel. |
| 15:00—15:20 | break |
| 15:20—15:50 | Ishan Sharma (Indian Institute of Technology Kanpur, India) "Regolith motion on small rubble asteroids" (abstract) |
| 15:50—16:20 | Takeshi Kawasaki (Nagoya Univ., Japan) "Unified understanding of nonlinear rheology near jamming" (abstract)When sheared slowly, jammed packings respond elastically before they yield. This linear elastic regime becomes progressively narrow as the jamming transition point is approached, and rich nonlinear rheologies such as shear softening and hardening emerge. However, the physical mechanism of these nonlinear rheologies is elusive. To clarify this problem, we investigate numerically jammed packings of athermal frictionless soft particles under quasi-static shear γ. We find the universal scaling behavior for the ratio of the shear stress σ and the pressure P, independent of the generation protocol of the initial configurations. Notably, we demonstrate shear-softening σ/P～γ^(1/2) over an unprecedentedly wide range of the strain up to the yield point, which a simple scaling argument can rationalize. |
| 16:20—16:50 | Kuniyasu Saitoh (Kyoto Sangyo Univ., Japan) "Shear-induced diffusion near jamming" (abstract) |
| 16:50—17:10 | break |
| 17:10—17:40 | Kiwamu Yoshii (Nagoya Univ., Japan) "Effect of particle cohesion and deformability on the rheology of dense systems" (abstract) |
| 17:40—18:10 | Michio Otsuki (Osaka Univ., Japan) "Scaling laws for velocity profile of granular flow in rotating drums" (abstract) |