<eases in the fabric of space-time. Though the notion seems to forbode some daunting task involving abstract phenomena, the theory is not so remote. On Thurs., Oct. 14, Carleton alumnus and astrophysicist Andrea Lommen ‘91 presented a lecture regarding the modern employment of pulsars in detecting “folds” in gravitational waves.
The presentation was titled, “Measuring Einstein’s Last Great Legacy: Wrinkles in Space-Time”. Lommen began with the basics. She explained that pulsars are “dead stars” that release two focused beams of radiation rendered by the high-powered magnetic fields that surround them. The pulsars rotate, and so do the beams; they follow what is commonly refered to as the “lighthouse effect.” Astronomers note when these beams intercept the Earth, as that reveals the period of rotation. The rate of rotation is so steady that the pulsar functions as a sort of universal clock.
A gravitational wave, she explained, is a “traveling perturbation in space, so the shape of space [is] actually changing as it travels through space.” It is the “traveling information that a gravitational force is changing,” creating “ripples in space-time.” Einstein’s theory of relativity predicts that this will happen when “two system of bodies” moving around one another “speed up.” The scientific community has yet to find concrete observations of gravitational waves, but there is a sizable amount of evidence supporting their existence.
In particular, scientists have found minute fluctuations in pulsar timing. They suspect that gravitational waves “warp” the space-time around the pulsar, interfering with the “pulses” traveling towards Earth.
So why does all of this matter? Not only would the “discovery” of gravitational waves deliver insight into the universe, it would be a new kind of “niche.” Until now, discoveries such as “radio telescopes, X-Rays, infrared” have developed the “electromagnetic spectrum.” Gravitational waves would deliver a new, almost revolutionary phenomenon.
During her talk, Lommen showed the audience a crinkled piece of paper. “Maybe there’s not as much rhyme or reason to the shape of space, and you don’t get these beautiful, concentric waves in space but rather, sort of a rippling like the ocean,” she said. There is perhaps not much tidiness in space. It seems rather that the universe is paradoxical and consistently arbitrary.