
Melvin Leok
Mon May 15, 2017
4:00 pm
Many gauge field theories can be described using a multisymplectic Lagrangian formulation, where the configuration manifold is the space of Lorentzian metrics. Groupequivariant interpolation spaces are critical to the construction of geometric structurepreserving discretizations of such problems, since they can be used to construct a variational...

Chrysoula Tsogka
Mon May 8, 2017
4:00 pm
We consider the problem of coherent imaging using intensityonly measurements. The main challenge in intensityonly imaging is recovering phase information that is not directly available in the data, but is essential for coherent image reconstruction. Imaging without phases arises in many applications such as crystallography, ptychography...

CANCELLED  James Faeder
Mon May 1, 2017
4:00 pm

Steven Wise
Mon Apr 24, 2017
4:00 pm
I will describe and analyze preconditioned steepest descent (PSD) solvers for fourth and sixth order nonlinear elliptic equations that include pLaplacian terms on periodic domains in 2 and 3 dimensions. The highest and lowest order terms of the equations are constantcoefficient, positive linear operators, which suggests a natural...

Lin Lin
Mon Apr 17, 2017
4:00 pm
The Fock operator, which appears in the widely used HartreeFock theory and KohnSham density functional theory with hybrid exchangecorrelation functionals, plays a central role modern quantum chemistry and materials science. The computational cost associated with the Fock exchange operator is however very high. In a simplified setting, the...

Yimin Zhong
Mon Apr 10, 2017
4:00 pm
We propose in this work a fast numerical algorithm for solving the equation of
radiative transfer (ERT) in isotropic media. The algorithm has two steps. In the first
step, we derive an integral equation for the angularly averaged ERT solution by taking
advantage of the isotropy of the scattering kernel, and solve the integral equation
with a fast...

Stefan Llewellyn Smith
Mon Apr 3, 2017
4:00 pm
A vortex in a straining field is a canonical situation describing vortices in an irrotational flow. Exact solutions to this problem have been found in the form of vortex patches and hollow vortices, both of which can be viewed as desingularizations of point vortices. After a review of the history of point vortices, we discuss hollow vortices,...