Inflation Theory

According to the standard cosmology model, in the current phase in the history of the Big Bang, the universe began about fourteen billion years ago. Initially the universe was hot and dense with interacting particles. It has been conjectured that prior to this phase, the universe underwent a brief period of accelerated expansion known as inflation when quantum fluctuations, stretched to cosmologically large scales, became the seeds of the universe’s stars and galaxies. According to inflation theory, as the universe expands exponentially fast, its geometry becomes flat—this geometry was confirmed experimentally around 2000. Theorists then had to use the laws of physics to solve the problem of how to make the inflation stop so that the universe cools and structure starts to form. 

Light is the great unifier. John Wheeler, the beloved Princeton physicist, used to draw the universe as a big capital U with a little eye on one leg, signifying that we, human beings, are the eyes of the universe looking back at...

“Space Ripples Reveal Big Bang’s Smoking Gun,” read the New York Times headline last March 17. In a seemingly momentous news conference at the Harvard–Smithsonian Center for Astrophysics, researchers using a BICEP (Background Imaging of...

In the public lecture “The Latest News from the Cosmos,” Matias Zaldarriaga, Professor in the School of Natural Sciences, explores the most detailed map of the infant universe to date. Publicly released on March 21, 2013, the...