MSU's Philipp Grete pays attention to detail, wins prestigious doctoral thesis award

Philipp Grete, a Michigan State University research associate in computational astrophysics, is this year’s sole recipient of the German Astronomical Society’s (AG) most outstanding dissertation in astronomy and astrophysics award.

Established in 1863, AG is a professional association of more than 800 astronomers and astrophysicists that encourages the dissemination of science education to the public and promotes research by recognizing outstanding scientists.

Grete completed his dissertation “Large eddy simulations of compressible magnetohydrodynamic (MHD) turbulence” last year at the Max Planck Institute for Solar System Science (MPS) and the Institute for Astrophysics at the University of Göttingen, Germany, qualifying him for the notable honor.

“The award feels great,” said Grete, who works with Brian O’Shea, associate professor in the Department of Physics and Astronomy in the MSU College of Natural Science. “This is a good closing of the Ph.D. thesis that was not always easy, so having such a successful finish is quite rewarding.”

Grete’s research aims to more fully understand and model the processes of magnetohydrodynamic (MHD) turbulence, key to illuminating the physics of the Sun and other stars, energetic matter streams and galaxy clusters.

“One problem we have in astrophysics is the large range of scales involved, from planets to galaxy clusters,” Grete explained. “We don’t have enough computational resources in the foreseeable future to simulate all the detail, so we developed a new model to incorporate effects of turbulent small scale motion.”

Grete’s innovative approach can account for sub-grid scale turbulence, the unresolvable motion below the computational grid, and reintroduce it into the simulation for a finer level of detail, a significant advance in his field.

“Imagine looking at a waterfall,” Grete said. “If you get very close, you see a lot of droplets and tiny whirls. The further away you get, it may be sufficient to say we have water flowing over an edge, but we are missing the details of the tiny droplets. We are using information from the overall picture to recover the effects of the motion of these tiny droplets.”

“I’d like to congratulate Dr. Grete on receiving this prestigious and highly competitive award—only one of these is awarded each year to students graduating from German universities, and the receipt of it speaks volumes to the high quality of his scientific efforts up to this point,” O'Shea said. "I’m delighted that Dr. Grete is continuing his excellent work here at Michigan State University.”

The more precise models will also provide new ways of studying the cosmos across disciplines.

“This method can be applied to different areas, especially in astrophysics,” Grete said. “Having this kind of recognition from the AG and astrophysics community is important to me and my work because it has been rather specific to fundamental physics and numerics up to this point.”  

Grete attended the annual AG meeting in Göttingen, Germany, earlier this month to receive the award and give a lecture about his dissertation.