Exploring Scientific
Progress Over Time
“Einstein, Gravitational Waves, Black Holes and Other Matters"
Presented by Gabriela González
Boyd Professor in the Physics and Astronomy Department at Louisiana State University
March 2, 2024
100 Thomas Building
11:00 a.m. to 12:30 p.m.
More than a hundred years ago, Einstein predicted that there were ripples in the fabric of space-time traveling at the speed of light: gravitational waves. Thirty years ago, when the Ashtekar Frontiers of Science lectures started, scientists were beginning to build detectors of those elusive waves, talking about the incredible technology that was needed. Decades later, on September 14, 2015, the LIGO detectors in Hanford, Washington and Livingston, Louisiana in the US registered for the first time ever a loud gravitational wave signal traveling through Earth, created more than a billion years ago by the merger of two black holes. Another spectacular signal was detected by LIGO and the Virgo detector in Europe in 2017, produced by the collision of two neutron stars giving birth to a black hole, generating also electromagnetic waves (light!) detected by many telescopes and helping us understand the origin of gold. In only a few years from the first detection, there are now more than 100 discovered signals from mergers of black holes and/or neutron stars - this is the era of gravitational wave astronomy. González will describe the history and details of the observations, and the gravity-bright future of the field.
Gabriela González is Boyd Professor in the Physics and Astronomy Department at Louisiana State University and works on searching for gravitational waves with the LIGO team. She was born in Córdoba, Argentina, where she studied before earning a doctoral degree at Syracuse University, in 1995. She was a staff scientist in the LIGO group at MIT, joined the faculty at Penn State in 1997 and moved to LSU in 2001. She has received awards from the American Physical Society, the American Astronomical Society and the National Academy of Sciences. She is a fellow of the American Academy of Arts and Sciences and a member of the US and Argentinian National Academies of Sciences. She has been a member of the LIGO Scientific Collaboration since 1997, served as spokesperson in 2011-2017, and participated in the announcement of the discovery of gravitational waves in 2016. Her group works on LIGO instrument development, reducing noise sources, and data diagnostics.
In 2004, the theme of the lecture series was “It’s About Time.” That year, Abhay Ashtekar, Atherton Professor and Emeritus Evan Pugh Professor of Physics and founder of the lecture series, presented a lecture titled "Time in the physical universe: From antiquity to Einsten and beyond."
Ashtekar will return to present a brief update on his research field and an overview of the 30 years of the lecture series before Gonzalez's lecture. Additionally, a 30th anniversary celebration will follow the talk.
Ashtekar was the founding director of the Penn State Institute for Gravitation and the Cosmos, which he led from 1992 to 2021. Ashtekar is a widely recognized leader in theoretical physics and focuses his research on classical general relativity and quantum gravity. Ashtekar’s most prominent and creative contribution to physics is his seminal reformulation of Einstein’s theory of general relativity as a gauge theory. The central piece of this reformulation is his discovery of a new set of canonical variables, now known as Ashtekar variables, that provided a powerful representation of canonical general relativity and led to an important branch of fundamental theory known as “loop quantum gravity.” His awards and recognitions include honorary doctoral degrees from the Université de la Méditerranée in Aix-Marseille, France, in 2010, and from the Friedrich Schiller University in Jena, Germany, in 2005. In addition, in 2004, he received a Forschungspreis Award from the Alexander von Humboldt Foundation in Germany. Ashtekar was honored with the Einstein Prize from the American Physical Society, which recognizes outstanding accomplishments in the field of gravitational physics, in 2018. Also in 2018, he was named an Evan Pugh Professor at Penn State. In 2016, he was elected as a member of the National Academy of Sciences, one of the highest honors accorded to U.S. scientists or engineers by their peers. Ashtekar is a Fellow of the American Association for Advancement of Science and the American Physical Society. He is one of only 51 Honorary Fellows of the Indian Academy of Sciences drawn from the community of scientists living outside of India. He has held the Krammers Visiting Chair in Theoretical Physics at the University of Utrecht, Netherlands; a Senior Visiting Fellowship of the British Science and Engineering Research Council; and the Sir C. V. Raman Chair of the Indian Academy of Science. In addition, he holds a visiting professorship at the Beijing Normal University and at the Inter-University Center for Astronomy and Astrophysics in Pune, India. Before joining the faculty at Penn State, Ashtekar held positions as professor, distinguished professor, and the Erastus Franklin Holden Professor of Physics at Syracuse University from 1984 to 1993. Previously, he was professor and held the chair of gravitation at the University of Paris VI in France.