Inflationary Cosmology: Is Our Universe Part of a Multiverse?

Course Description

This year lecture was given by the 2009 winner of the Isaac Newton medal, Professor Alan H Guth, Massachusetts Institute of Technology and was chaired by Professor Michael Rowan-Robinson, Imperial College.

The inventor of the inflationary universe model and this year’s Institute of Physics (IOP)’s Isaac Newton Medal winner, Professor Alan Guth from Massachusetts Institute of Technology, gave the Newton Lecture 2009 on Tuesday, 13 October.

His lecture, ‘Inflationary cosmology: is our universe part of a multiverse?’ was watched by physics students, academics, keen amateurs and a range of science dignitaries.

In the lecture, Guth discussed the evidence for his inflation modification of the big bang theory. His modification explains how the universe went through a period of exponential expansion in its very early history.

Moving onto the idea of a multiverse, Guth’s model predicts perpetual inflation and new “pocket universes”.

Guth also discussed the idea of environmental selection, aka the anthropic principle, which holds that we see a universe capable of supporting intelligent life because if it were different we wouldn’t be around to see it.

Guth recommended that the anthropic principle should be used only as an explanation of last resort, and why the principle disappoints many physicists who believe they should be able to predict fundamental values, and explained why he holds out some hope for answers from string theory.

Asked whether Guth himself believes in a multiverse, he replied, “Your guess is as good as mine. It’s certainly time to take the idea seriously.”