Gabriela González of Louisiana State University explained in this year’s Glover Memorial lecture that the gravitational waves that could ripple the fabric of space time in Albert Einstein’s theory did not become an observable reality until Sept. 14, 2015. According to Gonzalez, this new discovery has allowed scientists to measure gravitational waves from billions of solar mass systems and black holes.

Laser Interferometer Gravitational-wave Observatory (LIGO) detectors located in Louisiana and Washington showed on Sept. 14, 2015 that the gravitational waves had low frequency, but LIGO scientists used the frequency to calculate the masses of the black holes and the amplitude to determine how far apart they were from one another. In her lecture on Monday, Jan. 29, González explained that the scientists knew that the gravitational waves came from black holes because people who solved Einstein’s equations many years ago found that the curvature of space time changes as the black holes get closer together. However, gravitational waves are no longer produced once they have merged and there is a single floating black hole left.

Since then, González said, LIGO scientists have continued with the detection of smaller black holes. Additionally, using a large-scale space mission designed to detect gravitational waves (LISA), scientists are measuring radio signals from neutron stars in the galaxy in order to measure gravitational waves from billions of solar mass systems and black holes.

Nathan Stull ’21 considered González a quality presenter who explained the lecture in a manner that was fairly comprehensible to most people, without them needing to be astrophysicists.

Silke Kuhn ’21 agreed that González “managed to make her talk [on a difficult and complex subject] engaging and easy to grasp for everyone, regardless of any background knowledge.”

Attendee Aidan Pidgeon ’20 described his understanding of the lecture “like Galileo looking through his telescope and seeing the moons of Jupiter for the first time… For now, we cannot look further back in the universe than 380,000 years after the Big Bang because the universe was so dense at the time that light could not escape… with gravitational waves, we might actually be able to look further back than we can with light.”

Jordyn Schwartz ’21 was impressed with how science can now track black holes and understand what is outside of our universe. She also found herself more interested in exploring gravitational waves and understanding how black holes function and are formed. Schwartz also admitted that “it feels really great to have an intelligent woman here speaking confidently about science and math. That makes me really hopeful for my future and for the future of other women in science.”

Albert Einstein proposed that what Isaac Newton had named the force of gravity was the result of how large masses interact with the curvature of space and time in 1905. For example, when the Earth decides where to move in relation to the Sun, it assesses the curvature of space time and concludes that it is easiest to go around the sun. However, according to Einstein, such masses will not rotate around each other forever. General relativity proposes that, in the case of stars, a pair of black holes orbiting each other will eventually lose energy through the emission of gravitational waves and gradually approach one another over billions of years. González explained how radio signals show that certain stars revolving around one another are getting closer and closer today.

González hopes to continue discovering more signals and making further improvements, such as detecting pure signals from a rotating star and measuring gravitational waves with space detectors as technology continues to advance.

She announced that “gravitational waves astronomy is just the beginning!”

González’s presentation was the first Clarke Forum event of the spring semester. The speaker was also this year’s Glover Memorial Lecturer, a lectureship established in 1958 in memory of the inventor of the Glover Tower, John Glover of Newcastle-upon-Tyne, according to the Dickinson College website.