Alan Guth developed the idea of cosmic inflation as a junior particle physicist at Stanford University.
In 1981 he proposed that many features of our universe, including how it came to be so uniform and why it began so close to the critical density, could be explained by a new cosmological model which he called inflation. Inflation is a modification of the conventional big bang theory, proposing that the expansion of the universe was propelled by a repulsive gravitational force generated by an exotic form of matter.
Although Guth’s initial proposal was flawed (as he pointed out in his original paper), the flaw was soon overcome by Linde, then working in the Soviet Union.
Linde was investigating how the Universe might have heated up leading to the hot, dense conditions of a classical Big Bang. Linde soon recognized that a particular way of ending the inflationary epoch (called a “slow roll”) could solve some of the problems of the original model, while preserving most of its important features.
Linde went on to develop the idea of a chaotic, self-reproducing, inflationary universe.
In time, COBE (recognized by the 2006 Cosmology Prize) helped confirm their ideas of an inflationary Universe.
Guth and Linde are continuing to explore the impact of their ideas: Is our Universe a “brane”, part of an extra-dimensional structure? And what does inflation mean for the creation of matter, the nature of dark energy, and the fate of the universe?