Penn State LIGO Scientists Celebrate 2017 Nobel Prize in Physics

Penn State scientists and students on the Laser Interferometer Gravitational-Wave Observatory team (LIGO) are celebrating three LIGO leaders who have been honored today with the 2017 Nobel Prize in Physics. The Royal Swedish Academy of Sciences selected the three — Rainer Weiss, Barry C. Barish, and Kip S. Thorne — “for decisive contributions to the LIGO detector and the observation of gravitational waves,” which were predicted more than a century ago by Albert Einstein but were impossible to detect until the LIGO detectors accomplished the feat on September 14, 2015.

The Penn Staters who were coauthors of the paper that described this historic first-ever detection of gravitational waves are Sydney Chamberlin, Ryan Evererett, Lee Samuel Finn, Chad Hanna, Ashik Idrisy, Duncan Meacher, and Cody Messick. More who later joined Penn State’s LIGO research team are Andrea Sylvia Biscoveanu, Anuradha Gupta, Ryan Magee, Alex Pace, B.S. Sathyaprakash, and Jonathan Wang.

Chad Hanna, assistant professor of physics and of astronomy & astrophysics and Freed Early Career Professor at Penn State, has served as co-chair of LIGO’s Compact Binary Coalescence Group, which has detected all the gravitational waves discovered thus far. “The Nobel Prize awarded today for LIGO’s discovery of gravitational waves two years ago is a testament to the tremendous importance that the scientific community has attributed to LIGO’s results. While we are celebrating today’s news, we also are joyfully contemplating the unimaginable discoveries yet to come as LIGO and other instruments, including the new Virgo gravitational-wave detector in Italy, continue to listen to the sounds of the cosmos,” Hanna said.

“It took 100 years to confirm the existence of gravitational waves but our observations over the past two years have already raised questions about the formation and evolution of black holes, and have allowed us to test Einstein’s gravity theory to incredibly greater precision than was possible before,” said B. S. Sathyaprakash, Elsbach Professor of Physics and Professor of Astronomy and Astrophysics at Penn State. “We are beginning to understand if Nature’s black holes are truly spacetime warpage as predicted by general relativity and if the nature of gravitational waves is as predicted by Einstein. The LIGO-Virgo network of detectors have truly begun a new chapter in astronomy. This year’s prize is a befitting reward to this new endeavor, which promises to provide deeper insights into how the universe works.”

Abhay Ashtekar, Holder of the Eberly Family Chair in Physics and Director of the Institute for Gravitation and the Cosmos at Penn State (IGC), said that, during the past two decades, the IGC institute has played a leadership role in developing the field of gravitational-wave science that lies at the interface of several disciplines. “Early on, the U. S. National Science Foundation awarded a Physics Frontier Center to IGC. Over a seven-year period, the IGC institute hosted a large number of workshops and focus sessions that brought together scientists from diverse areas that previously had been disparate including general relativity, computational science, relativistic astrophysics, data analysis and statistics. These initiatives helped to crystallize the then nascent field of gravitational-wave science.”

More recently, Ashtekar said, “research teams led by the IGC faculty members Chad Hanna and B. Sathyaprakash have played a seminal role in the discoveries that were awarded this year’s Nobel prize. Hanna is the co-chair of the compact binaries group that made the discoveries. Methods developed by Sathyaprakash over the past 25 years lie at the foundation of the way signal is extracted and analyzed and the way source parameters are determined. He has also served on the LIGO executive committee and was the chief coeditor of the last Physical Review Letters paper, cited by the Nobel Committee, on gravitational waves resulting from the merger of two black holes.”

Ashtekar noted that the IGC institute is poised to shape developments in the emerging field of gravitational-wave science throughout the next decade. “Two years ago Professors Hanna and Sathyaprakash initiated a series of conferences on ‘Physics and Astrophysics at the Extreme’ (PAX), which have been high-profile international events,” he said. “The next PAX conference will return to Penn State in February 2018. It promises to be even more exciting because of these very recent gravitational wave discoveries.”