
Speaker:Title: On the wave turbulence theory for a stochastic KdV type equationVenue: CMSA Room G10Random Matrix & Probability Theory Seminar Speaker: MinhBinh TRAN (SMU & MIT) Location: CMSA, Room G02** Title: On the wave turbulence theory for a stochastic KdV type equation Abstract: We report recent progress, in collaboration with Gigliola Staffilani (MIT), on the problem of deriving kinetic equations from dispersive equations. To be more precise, starting from the stochastic ZakharovKuznetsov equation, a multidimensional KdV type equation on a hypercubic lattice, we provide a derivation of the 3wave kinetic equation. We show that the two point correlation function can be asymptotically expressed as the solution of the 3wave kinetic equation at the kinetic limit under very general assumptions: the initial condition is out of equilibrium, the dimension is $d\ge 2$, the smallness of… 

Speaker: MinhBinh TRANTitle: On the wave turbulence theory for a stochastic KdV type equationVenue: VirtualAbstract: We report recent progress, in collaboration with Gigliola Staffilani (MIT), on the problem of deriving kinetic equations from dispersive equations. To be more precise, starting from the stochastic ZakharovKuznetsov equation, a multidimensional KdV type equation on a hypercubic lattice, we provide a derivation of the 3wave kinetic equation. We show that the two point correlation function can be asymptotically expressed as the solution of the 3wave kinetic equation at the kinetic limit under very general assumptions: the initial condition is out of equilibrium, the dimension is $d\ge 2$, the smallness of the nonlinearity $\lambda$ is allowed to be independent of the size of the lattice, the weak noise is chosen not to compete with the weak nonlinearity and… 

Speaker: Alberto BracciTitle: Macroscopic properties of buyerseller networks in online marketplacesVenue: VirtualAbstract: Online marketplaces are the main engines of legal and illegal ecommerce, yet the aggregate properties of buyerseller networks behind them are poorly understood. We analyse two datasets containing 245M transactions (16B USD) between 2010 and 2021 involving online marketplaces: 28 dark web marketplaces (DWM), unregulated markets whose main currency is Bitcoin, and 144 product markets of one regulated ecommerce platform. We show how transactions in online marketplaces exhibit strikingly similar patterns of aggregate behavior despite significant differences in language, products, time, regulation, oversight, and technology. We find remarkable regularities in the distributions of (i) transaction amounts, (ii) number of transactions, (iii) interevent times, (iv) time between first and last transactions. We then show how buyer behavior is… 

Speaker:Title: GromovWittenDonaldson Thomas theory and BirationalSymplectic invariants for algebraic surfacesVenue: VirtualDuring the Spring 2021 Semester Artan Sheshmani (CMSA/ I.M. A.U.) will be teaching a CMSA special lecture series on GromovWitten/Donaldson Thomas theory and Birational/Symplectic invariants for algebraic surfaces. In order to attend this series, please fill out this form. The lectures will be held Mondays from 8:00 – 9:30 AM ET and Wednesdays from 8:00 – 9:00 AM ET beginning January 25 on Zoom. You can watch Prof. Sheshmani describe the series here. 

Speaker:Title: Special Lecture Series on Derived AlgebraicDifferential GeometryVenue: VirtualIn the Spring 2019 Semester, the CMSA will be hosting a special lecture series on Derived algebraic/differential geometry run by Artan Sheshmani, with lectures given by Prof. Sheshmani and Dr. Dennis Borisov. The seminar will be held on Tuesdays and Thursdays from 3:004:30pm in CMSA, room G10. Click here for reference material Click here for a syllabus Schedule: Section 1: Basic setting of derived geometry The goal: To collect the minimum set of tools needed to do algebraic geometry in the derived context. 2/05/2019 Lecture 1: Model and сcategories Video 2/07/2019 Lecture 2: Grothendieck topologies and homotopy descent Video 2/12/2019 Lecture 3: Derived Artin stacks Video 2/14/2019 Lecture 4: Cotangent complexes Section 2: Loop spaces and differential forms… 














