Berkeley Labs has been abuzz with excitement over Tuesday morning’s announcement that LBL and UC Berkeley astrophysicist Saul Perlmutter won this year’s Nobel prize in physics, most notably for his research into dark energy and the accelerating expansion of the universe. Saul is the 11th LBL scientist and 9th UC Berkeley faculty member to be awarded a Nobel prize, and he brings UC Berkeley’s running total of Nobel prizes to a whopping 22.
Earlier this year, I attended a lecture that Perlmutter gave to a public audience at the International House entitled “Stalking Dark Energy and the Mystery of the Accelerating Universe.” Every seat was taken, but that didn’t stop overflow attendees from sitting in the aisles and peaking through the doors. The rock star treatment was a testament to the public’s interest in Saul and his fascinating research topic.
It has been known for some time that the universe is expanding, but whether or not it would eventually stop growing had long remained an open question. One popular theory at the time was that the expansion universe would eventually stall out due to the inward pull of gravitational forces. But Perlmutter surprised the scientific community by showing – through the observance of light from supernovas – that not only would the universe continue to expand, but that it would do so at an accelerating rate. For the universe to accelerate outward past the collapsing force of gravity, there must be another force propelling it away. That force is what we now call dark energy, the “mysterious something” that comprises 73% of our universe.
Congratulations to Saul. A comment given by Bob Cahn, head of the cosmology group at LBL, sums it up nicely: “This is the biggest discovery in the history of science, and will remain so forever, since it only leaves 25% for everyone else.”