The Imaging and Computing Group (ICG) studies **inverse problems** related to
wave scattering and high-frequency data.

The group‘s research directions include computational wave propagation, fast numerical algorithms, applied harmonic analysis, nonlinear signal processing, convex optimization, and the mathematics of sparse and separated expansions. The problems we consider are often motivated by real-life challenges in seismic and radar imaging.

We are always on the lookout for talented people to join the group!

# Research Highlights

**When is superresolution of sparse signals possible?
** We quantify regimes of stable super-resolved recovery of sparse signals
from bandlimited measurements. In the case of adversarial deterministic noise of ...read more

**A scalable solver for the Helmholtz equation.
** We present a numerical method for the 2D high-frequency Helmholtz equation with online parallel complexity that scales
sublinearly as O(N/L), where N is the number ...read more

**Convex recovery from interferometric measurements.
** We show a deterministic stability result for the recovery of vectors from interferometric measurements, which have important
applications in model-robust ...read more

**Matrix probing: randomized
fitting for the
wave-equation Hessian.** What can be determined about the
pseudoinverse *pinv(A)* of a matrix A from one
application of A to a vector of random entries? A ...read more

**A butterfly algorithm for
synthetic aperture radar imaging.** We propose what is perhaps the
first O(N log N) controlled-accuracy algorithm for SAR imaging. We use the
butterfly scheme, an alternative to the FFT ...read more

**Wave computation with
Fourier integral operators.** We propose a new time upscaling
method to avoid the CFL condition for acoustic wave propagation in a
smooth heterogeneous medium, by numerically representing ...read more

# News and Events

September 2019

Welcome Philippe Ricoux (RS), Chenguang Zhang (postdoc), and Adrien Scheuer (postdoc) to the group!

May 2019

Congratulations to Charles-Henri Clerget, former postdoc in the group, whose team Acoustic Wells won the grand prize in the MIT $100K Entrepreneurship Competition.

September 2018

Welcome Zhilong Fang (postdoc) to the group!

September 2018

Welcome to Sarah Greer, graduate student in the new CSE-math graduate program. We are also proud that Sarah is one out of 25 recipients of a DOE CSGF graduate fellowship this year. Congrats!

2015

Announcing PySIT: Python Seismic Imaging Toolbox v0.5. Check pysit.org.

Updated, April 2018

Current Job Posting - Postdoc positions. See the openings page for descriptions.