Are we living in a multiverse? Eternal inflation, bubbles, and cosmic collisions

About a decade ago, we completed an epochal transformation in the understanding of our cosmos, unraveling a broad and deep understanding of how the observable universe has evolved from a hot, dense state 13.7 billion years ago. Yet a second, even bigger transformation may now be taking place, because this understanding points to a crucial early epoch of "inflationary" cosmic expansion, during which it expanded at a stupendous rate to create the vast amount of space we can observe. But cosmologists are coming to believe that inflation may do much more: in many versions, inflation goes on forever, generating not just our observable universe but also infinitely many more such regions with similar or different properties, together forming a staggeringly complex and vast "multiverse". Dr. Aguirre will trace the genesis of this idea, explore some of its implications, and discuss how cosmologists are currently seeking ways to empirically test this idea by actually searching for hints of other "universes".

Speaker: Anthony Aguirre, Department of Physics and Santa Cruz Institute for Particle Physics, UC Santa Cruz

Editors note:  Start time has been corrected from previous listings.