A Nobel laureate and two Harvard professors commemorated the 50th anniversary of research that validated the “big bang” Thursday with a series of speeches.

Speaking to a crowded audience about theories concerning the origin and future of the universe, the panelists reflected on the discovery of cosmic microwave background radiation that garnered widespread acceptance of the theory.

Two Harvard professors, one from the Massachusetts Institute of Technology, and a 1978 Nobel laureate in physics Robert W. Wilson, contributed to the talk as scientists who had conducted vital background radiation research.

Alan H. Guth, an MIT physics professor, spoke first about prominent competing theories for the origin of the universe before the “big bang” had gained widespread acceptance.

“It may be hard to conceive that the ‘big bang’ theory was not [at one time] the only theory that everybody thought was right,” said Gouth, pointing to the now out-of-date “steady state” theory.

Wilson recounted that when he was taught “steady state” theory, he liked the theory on philosophical grounds. He added that recent progress in the field of cosmology and his own research has further interested him in the subject.

“It has been very satisfying to see how this has developed,” Wilson said.

Robert P. Kirshner, the Clowes Professor of Science at Harvard, joked that he typically sees instructors and students alike possessing an egocentric view of the universe

Showing a comical diagram of the universe with a stick-figure man at the center, Kirshner said that faculty and students alike think “that they are the center of things.”

Kirshner went on to say that only four percent of the universe consists of atoms, while dark energy and cold dark energy make up the remaining portion of the universe. Even though scientists can figure out proportional numbers about the composition of the universe, he noted, mysteries still remain.

The last of the talks focused on theories on the future of the universe from Avi Loeb, the chair of Harvard’s Astronomy Department.

Loeb said that while the majority of cosmology focuses on the inanimate, he wanted to “bring [humans] into the picture” by taking up the task of conceptualizing the future of the universe.

Addressing the fact that the universe is expanding at an increasing rate, Loeb said that eventually the speed of expansion of distant stars and galaxies will approach the speed of light. In such circumstances, those celestial bodies would no longer be visible to the earth. According to Loeb, if extraterrestrial life were to try to contact humans, it would be impossible.

Speakers joked that as the universe changes over millions of years, they hope their work will be cited.

—Staff writer Theodore R. Delwiche can be reached at theodore.delwiche@thecrimson.com.