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- Moments In Time8:00 am
- GRS Dissertation Defense of Natalie M. Laudicina9:00 am
- Dunkin' Next Generation Grand Opening11:00 am
- ECE Seminar Speaker - Berkay Celik11:00 am
- Mishloach Manot Pick-Up & Bake Sale11:00 am
- GRS Dissertation Defense of Taylor Hall11:00 am
- GRS Dissertation Defense of Yeonha Jung11:00 am
- Silence Practice12:00 pm
- Returning to Work After a Break Webinar12:00 pm
- Drop-In Writing Assistance 12:00 pm
- Bioinformatics Sponsored Systems Biology Seminar12:45 pm
- MSE PhD Prospectus Defense of Alexander Saeboe1:00 pm
- COM - How to Write a Cover Letter1:00 pm
- Faculty Advisor Workshop1:00 pm
- Tea Time 3:30 pm
- Lagrangian chaos and scalar mixing in stochastic fluid mechanics (Sam Punshon-Smith -- Brown)4:00 pm
- "Outrage": The 9th Annual Sedgwick Memorial Lecture by Robyn Wiegman4:00 pm
- The First Women of Theology4:00 pm
- Panel Discussion – International Migration and Diaspora in World Politics – Prof. Thomas Berger, Prof. Joseph Wippl, Karsten Voigt4:40 pm
- Yawkey Studio5:00 pm
- Uses of the Past in Divided Societies: Northern Ireland and the US — A Lecture by Olwen Purdue5:00 pm
- Mind, Body, and Spirit Yoga5:00 pm
- Funding Panel Series: Four Ways to Raise Money for Your Idea5:30 pm
- Film Screening and Discussion: Ballad of a Righteous Merchant, by Herbert Golder6:00 pm
- Looking at Morocco from Inside and Outside6:00 pm
- Willing Suspension's Friar Bacon and Friar Bungay7:00 pm
- "Ballad of a Righteous Merchant " Film Screening (South Campus)7:00 pm
- Conversations – John Keats: the Great Year of his poems, 18197:00 pm
- Piano Departmental Recital8:00 pm
Lagrangian chaos and scalar mixing in stochastic fluid mechanics (Sam Punshon-Smith -- Brown)
Lagrangian chaos refers to the chaotic behavior of Lagrangian trajectories in a fluid. This chaotic behavior often characterized by a positive Lyapunov exponent, namely the property that initially close trajectories will separate at an exponential rate after long time. In this talk we will consider a variety of stochastically forced fluid models, including the 2 dimensional Navier-Stokes equations, and show that under certain non-degeneracy conditions on the noise, the stochastic flow possesses a positive Lyapunov exponent. The proof crucially uses the theory of random dynamical systems as well as tools from Malliavin calculus and control theory to satisfy a certain non-degeneracy criterion originally due to Furstenberg. We will explore several important consequences of a positive exponent for passive scalars advected by the fluid. For instance, as a corollary it is straight forward to rigorously prove Yaglom's law, an analogue of Kolmogorov's famous 4/5 law for passive scalar turbulence. More importantly, one can show almost sure exponential decay in time of passive scalars in any negative Sobolev norm (exponential mixing) by using the positive exponent to show geometric ergodicity of the two point Lagrangian motion.
When | 4:00 pm to 5:00 pm on Thursday, March 21, 2019 |
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Location | 111 Cummington Mall - MCS 148 |