時間：12月17日(四) 13：20

題目：The emergence of collective modes, ecological collapse and directed percolation at the laminar-turbulent transition
講者：施宏燕 研究員

服務單位：中央研究院 物理研究所

地點：本校科學三館1樓 110室

對象：本所博士生及碩士生、或其他有興趣之師生

摘要：

How a laminar flow becomes turbulence has been an unsolved problem for more than a century and is important in various industrial applications. Recently precise measurements in pipe flow experiments showed non-trivial spatiotemporal complexity at the onset of turbulence where lifetime and splitting time of metastable turbulence do not diverge asymptotically as would have been expected in a sharp transition.
Based on numerical evidence from the hydrodynamics equations, we discovered the surprising fact that the fluid behavior at the transition is governed by the emergent predator-prey dynamics of the important long-wavelength mode, leading to the mathematical prediction that the laminar-turbulent transition is analogous to an ecosystem on the edge of extinction. This prediction demonstrates that the laminar-turbulent transition is a non-equilibrium phase transition in the directed percolation universality class, and provides a unified picture of transition to turbulence emerging in systems ranging from turbulent convection to magnetohydrodynamics.

Reference:
[1] Hong-Yan Shih, Tsung-Lin Hsieh and Nigel Goldenfeld, Nature Physics 12, 245 (2016)
[2] https://www.nature.com/collections/rxsztdqblr

離開校園一年的物理所校友，面對的是什麼責任？什麼競爭的環境？什麼背景的同事？什麼工作壓力？什麼知識上的不足？⋯⋯
畢業前，同學們總會有許多的憧憬與好奇。
開業典禮當天(6/1)下午，物理所準備了一份畢業小禮物，額外加演了一場「在物理所最後的seminar」。
邀請離開物理所一年，在工研院的副工程師黃師揚學長回來回答大家的問題。
現場備有茶點，是個informal的經驗交換，歡迎畢業生、在校生，以及家長等一同參加。

• 時間：6/1(六)16:10 – 17:10
• 地點：本校基礎科學教學研究大樓3樓SC353會議室
• 講題：在物理所最後的seminar—給畢業生的就業秘笈
• 主講人：工研院黃師揚副工程師
  主持人：張正宏副教授
  對象：本所畢業生、在校生、以及家長等。