# Seminars

# AMCS Graduate Seminar | The Phase Retrieval Problem

Start Date: March 23, 2017

End Date: March 23, 2017

*By Professor Yang Wang
**Dean of Science, Chair Professor of Department of Mathematics, **Hong Kong University of Science and Technologyâ€‹*

In many applications such as X-ray Crystallography, communication, imaging and others one must construct a function/signal from only the magnitude of the measurements. These measurements can be, for example, the Fourier transform of the density function. While it is well known that we can recover a function from its Fourier transform, the classical phase retrieval problem asks whether we can recover a function from only the magnitude of its Fourier transform. More generally, the phase retrieval problem refers to the reconstruction of a signal from only the magnitude of its linear measurements. The problem, even in the finite dimensional setting, turns out to be a very challenging mathematical problem and remains unsolved. It has surprising links to a many other problems in science and engineering, and to the classical problems on the embedding of manifolds into Euclidean spaces. In this talk I'll give an overview of the problem and discuss some of the recent progresses, on both the theoretical and application sides.

**BIOGRAPHY**: Professor Yang Wang is Dean of Science and chair professor of mathematics in the Hong Kong University of Science and Technology. An internationally respected mathematician, his research spans both pure and applied mathematics, including applied harmonic analysis, signal processing, fractal geometry, tiling and the application of machine learning to various practical applications. He is on the editorial board of some of the top journals in his fields, such as Applied and Computational Harmonic Analysis, Advances in Computational Math etc.
Professor Wang received his BS in mathematics from the University of Science and Technology of China in 1983 and his PhD in mathematics from Harvard University in 1990. He was a professor at Georgia Tech until 2006, when he became department head in Michigan State University. He has also served as a program director in the US National Science Foundation, and an active member of the mathematical community in promoting outreach and international exchange.

### More Information:

*Prof. Ying Wu: email: Ying.Wu@kaust.edu.sa*

**For more info contact:**Date: Thursday 23

^{rd}March 2017

Time:12:00 PM - 01:00 PM

Location: Location: Bldg. 9 - Lecture Hall 1

Refreshments: Lunch bags will be served at 11:45 AM