Gravitational waves discovered, Universe exploration continues
April 14, 2016
Professor Emeritus of Physics & Astronomy Jeff Bowen shared groundbreaking news with the campus on April 11: gravitational waves have been detected for the first time in the history of mankind. Scientists at the Laser Interferometer Gravitational-Wave Observatory (LIGO) observed these ripples, which have arrived on earth from some cataclysmic event in the distant universe in the fabric of space-time.
After making this announcement to the audience, Bowen proceeded to explain the origins of the theory and the geometry behind the natural phenomenon. In 1915, Albert Einstein had predicted in his theory of general relativity that there were gravitational waves at work. The recent revelation confirms his hypothesis and opens up an unprecedented new window into the cosmos.
Bowen reviewed Einstein’s field equations, as well as the geometric applications that are used to calculate gravitational waves. Physics students saw many connections to topics covered in their classes as they approached this challenging material.
“How do you connect geometry to gravity?” Bowen said.
Once the math behind the gravitational waves had been completed, Bowen moved onto definitions of gravitational waves and how they work. According to LIGO, gravitational waves are “ripples” in the fabric of space-time caused by some of the most violent and energetic processes in the universe. These ripples travel at the speed of light and carry useful clues regarding the true nature of gravity itself.
“Take two black holes, throw them at each other at an angle, and let them rotate around each other,” Bowen said, describing the generation of a gravitational wave. “When you’re done, you end up with one big black hole. The gravitational wave is an oscillation that stretches and compresses.”
Bowen also took time to demonstrate how the LIGO crew was able to make this scientific breakthrough and detect the gravitational waves.
“LIGO uses an interferometer,” Bowen said. “It is the most sensitive measuring instrument ever made.”
The LIGO interferometers work by merging two or more sources of light to create a measurable interference pattern. Before the instrument, the effect of gravitational waves was so small that it proved immeasurable. This new development has allowed the researchers to measure the movement of the wave, which will prove crucial as astronomers and physicists attempt to study the universe in new ways.
Students were inspired by this revolutionary breakthrough in the field of astrophysics.
Bowen’s presentation now has University students asking important questions about the future, one of which must be on everyone’s mind. Where will this discovery take us in our journey to explore the universe?