Student Spotlight: Jesse Adams

The following article was written by Jesse Adams for the 2018 Applied Math newsletter:
As I entered my final undergrad year as a computer engineering student, I came to the conclusion that I assume most people do: I just do not have enough math in my life! This led me to pursue a masters degree in math, which in turn brought me to the Applied Math PhD Program at Arizona. I have always had a love for learning, and this path has allowed me plenty. Although this certainly has not been the path of least resistance, it has been a worthwhile one.

After surviving a grueling first year and a challenging second, my hard work paid off as I obtained a summer internship at the Nevada National Security Site (NNSS) in Las Vegas. This is, of course, the perfect place to spend a summer, getting away from the desert heat in Tucson. My position was in the Signal Processing and Applied Math group, where I was first introduced to Uncertainty Quantification. I specifically began working on computational inverse problems in X-ray radiography. The combination of mathematics, statistics, and computational difficulties brought me to a new realm which I have no intent on leaving. My boss, Dr. Aaron Luttman, at the NNSS was happy to hear this and offered partial funding for the rest of my time at Arizona.

With this offer in hand, I had the task of finding a professor in the department who would become my co-advisor with Dr. Luttman. I was immensely fortunate that a new hire, Dr. Matthias Morzfeld, had just arrived on campus, and had yet to fill his plate with students. Upon our first meeting, his passion and knowledge in the field were evident, and the deal was done. Dr. Morzfeld became my advisor. Without both Dr. Luttman and Dr. Morzfeld, I most surely would not be where I am today.

Along with the projects from the NNSS, during my 3rd and 4th year I worked on a problem with Dr. Morzfeld stochastically modeling the geomagnetic dipole of the Earth’s magnetic field. Previous models were characterized by two components: a deterministic drift term modeling resolved dynamics, and the stochastic term for turbulent fluid motion in the Earth’s core. These models performed well over “short” time periods (on the order of 2 million years), but were suspect over longer time periods (150 million years), as they lacked the ability to produce superchrons: periods of time in excess of 10 million years where no pole reversals occurred. We were able to extend two models to better match the data by using data assimilation techniques, as shown in the figure. These results, along with work from Math graduate student Spence Lunderman and undergraduate Math student Rafael Orozco, was published in Nonlinear Processes in Geophysics under the title Feature-based data assimilation in geophysics.

At the same time, and over the summers, I continued working with the NNSS on several problems involved in X-ray imaging. At the NNSS, hydrodynamic materials experiments are performed, and the primary source of data for these are X-ray images. One part of maximizing the information gleaned from these images is to remove the blur caused by the system, while not amplifying the noise in the image. We also aim to quantify the uncertainty in the images. In my thesis work we have implemented an algorithm capable of deblurring large images, while avoiding artifacts inherent in Fourier methods.

As my time at Arizona comes to a close, I know there is much I will miss. As an outdoorsy-type from Montana, I was initially wary of the desert life. But I quickly came to love the backpacking, mountain biking, and climbing ventures available surrounding Tucson. Luckily for me, I get to continue living the desert life as a postdoc at the NNSS. And I will finally get to experience Las Vegas during a time of the year when the air does not feel like it is roasting my lungs! I will forever be grateful for the friends I have made, my amazing advisors, and the outstanding professors I have had while at Arizona. With all their help, I am excited to finally start my career as a mathematician.

Jesse Adams, (PhD, May 2019), will join the Nevada National Security Site (NNSS) as a post-doctoral researcher in May, 2019. An article about Jesse's exciting and impactful research can be found here in the NNSS News.  Congratulations, Jesse!