100 years after Einstein's prediction Physics prof, students play crucial role in gravitational waves discovery


Dr. Josh Willis, associate professor of physics at Abilene Christian University (ACU), along with a current ACU student and two ACU graduates, was involved in research related to the February 11th announcement of the discovery of gravitational waves–wrinkles in the very fabric of space-time. The discovery confirms a major prediction of Albert Einstein’s 1915 general theory of relativity and opens an unprecedented new window onto the cosmos.

"So, the big announcement is that it's the first time we've seen gravitational waves but we're at least as excited about what else we'll see -- how many systems like this are out there, how far away they are, how massive they are, things like that," Willis said.

Gravitational waves carry information about their dramatic origins and about the nature of gravity that cannot otherwise be obtained. Physicists have concluded that the detected gravitational waves were produced during the final fraction of a second of the merger of two black holes to produce a single, more massive spinning black hole. This collision of two black holes had been predicted but never observed.

“This first observation is important not only in and of itself, but because it represents the dawn of a new kind of astronomy,” Willis said, “We have been able to see the universe, but not yet hear it, and now we can. This will allow us to observe dramatic events in the universe that may not be visible to telescopes, and to learn directly properties of such events that can be hard to measure even when they do give off light or radio waves, microwaves, or other conventional signals that we can detect with telescopes.”

The gravitational waves were detected on September 14, 2015, at 5:51 a.m. Eastern Daylight Time by both of the twin Laser Interferometer Gravitational-wave Observatory detectors, located in Livingston, Louisiana, and Hanford, Washington, USA. The LIGO Observatories are funded by the National Science Foundation (NSF), and were conceived, built, and are operated by Caltech and MIT. The discovery, accepted for publication in the journal Physical Review Letters, was made by the LIGO Scientific Collaboration which includes the GEO Collaboration and the Australian Consortium for Interferometric Gravitational Astronomy and the Virgo Collaboration using data from the two LIGO detectors.

Every year since 2011, Dr. Willis has spent several months as a visiting scientist in the data analysis group of the Max Planck Institute for Gravitational Physics in Hannover, Germany and since 2014 he has spent time working on optimization of data analysis pipelines for the LIGO Laboratory operated by Caltech University. Dr. Willis has been one of the senior lead developers on the PyCBC data analysis pipeline used in the discovery.
LIGO research is carried out by the LIGO Scientific Collaboration (LSC), a group of more than 1,000 scientists from universities around the United States and in 14 other countries. More than 90 universities and research institutes in the LSC develop detector technology and analyze data; approximately 250 students are strong contributing members of the collaboration.

Hannah Hamilton from Abilene, currently a senior physics major at ACU, has been involved in analysis of data for LIGO. Andrew Miller, a 2014 graduate of ACU, worked on development of the PyCBC code and spent a summer in working at the Max Planck Institute with Willis, funded through the ACU Pursuit program. Marissa Walker, a 2011 graduate of ACU, is now a Ph.D. student at Louisiana State University, working on LIGO.

Abilene Christian University’s robust science programs have merited the expansion of existing facilities to include the new 85,000 square foot Robert R. and Kay Onstead Science Center that will house classrooms, labs and offices for the four ACU science departments – biology, chemistry and biochemistry, engineering and physics, and mathematics, the Halbert-Walling Research Center, a 54,000-square-foot building for science labs, classrooms and offices, as well as renovations that will create classroom, laboratory and office space for the fast-growing engineering and physics department.