2011 Nobel Prize in Physics Special
In 1917, Albert Einstein added a constant — a sort of ‘fudge factor’ — to his Theory of General Relativity to counteract the force of gravity and keep his Universe static — that is, not expanding, not contracting. A few years later, Edwin Hubble proved the Universe wasn’t, in fact, static but expanding — consistent with Einstein’s theory without the constant. Upon hearing this, Einstein describe his incorporation of this constant into General Relativity as the biggest blunder of his life.
Seventy years later, Saul Perlmutter, Brian P. Schmidt, and Adam G. Riess found something far more radical. Casting their telescopes towards certain types of supernova, they discovered the Universe isn’t just expanding, it’s expanding at an accelerating rate — prompting physicists to put back Einstein’s cosmological constant back into his equations… but with value that he never would have dreamed.
So what does it all mean? We put this question to Ofer Lahav, Perren Professor of Astronomy at University College London. And we discover that it’s all just the first instalment of a still-unfolding story whose second part is yet to be written.