MSMoD49
Rare Events in Complex Physical Systems  Part I of IV
For Part II, see MSMoE49
For Part III, see MSTuD49
For Part IV, see MSTuE49
Date: August 10
Time: 13:3015:30
Room: 107
(Note: Click title to show the abstract.)
Organizer:
Cameron, Maria (Univ. of Maryland)
Li, Tiejun (Peking Univ.)
Lu, Jianfeng (Duke Univ.)
Weare, Jonathan (Univ. of Chicago)
Zhou, Xiang (City Univ. of Hong Kong)
Abstract: Many problems arising from chemistry, physics and materials science involve rare but significant exit events and/or transition events between stable states. The transitions happen on a time scale much longer than the intrinsic time scale of the dynamical system. Examples of such events are conformational changes of biomolecules, chemical reactions, etc. The purpose of this minisymposium is to bring together experts working in theory, numerical algorithms and application issues, such as analysis of models for metastable systems, free energy calculation, importance sampling, accelerated dynamics, and sampling of transition pathways.
MSMoD491
13:3014:00
Metastability, spectra and eigencurrents of networks representing energy landscapes
Cameron, Maria (Univ. of Maryland)
Abstract: Computational tools for spectral analysis of large stochastic networks representing energy landscapes
of atomic and molecular clusters are proposed:
(i) an efficient algorithm for computing zerotemperature asymptotics for eigenvalues and eigenvectors of the generator matrices, and (ii) a continuation technique for computing selected eigenpairs of interest at finite temperatures and corresponding eigencurrents. Applications to Wales group's networks representing LennardJones clusters of 38 and 75 atoms whose energy landscapes have doublefunnel structures will be presented.
MSMoD492
14:0014:30
An adaptive stepsize string method and its convergence to the minimum energy path
Zhang, Lei (Peking Univ.)
Abstract: Finding minimum energy path (MEP) on a potential energy surface is of great interest in understanding the barriercrossing events. We develop an adaptive stepsize string (ASS) method by treating classical string method as a minimization process of the FriedlinWentzell functional. Optimization method can then be applied in the ASS to speed up the computation. Numerical analysis shows the action can measure how far from one path to MEP and proves the local convergence.
MSMoD493
14:3015:00
Evolving Junctions on Obstacle Boundaries (EJOB) method for the
shortest path problems
Zhou, Haomin (Georgia Inst. of Tech.)
Abstract: In this talk, I will use the shortest path problem, finding
the shortest path connecting two points while avoiding obstacles
in a region, as an example to illustrate how one can use stochastic differential equations (SDEs) to solve some challenging real world problems. On the
other hand, the algorithm introduces new, but challenging, mathematical
problems in dynamical systems and PDEs that have not been studied in the
past. This presentation is based on joint work with ShuiNee Chow (Math,
Georgia Tech), Yancy DiazMercado (ECE, Georgia Tech),
Magnus Egerstedt (ECE, Georgia Tech), Wuchen Li (Math, Georgia Tech)
Jun Lu (Wells Fargo).
MSMoD494
15:0015:30
The string method for saddle point search
REN, WEIQING (National Univ. of Singapore & IHPC)
Abstract: In this talk, we show how the string method, which was originally developed to compute minimum energy paths between two metastable states, can be used to compute saddle points for a given minimum of the potential or free energy. These saddle points act as bottlenecks (i.e. transition states) for barriercrossing events. Application to the wetting transition on patterned surfaces will be presented.
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Footnote: Code: TypeDateTimeRoom No.
Type : IL=Invited Lecture, SL=Special Lectures, MS=Minisymposia, IM=Industrial Minisymposia, CP=Contributed Papers, PP=Posters
Date: Mo=Monday, Tu=Tuesday, We=Wednesday, Th=Thursday, Fr=Friday
Time : A=8:309:30, B=10:0011:00, C=11:1012:10, BC=10:0012:10, D=13:3015:30, E=16:0018:00, F=19:0020:00, G=12:1013:30, H=15:3016:00
Room No.: TBA
