The 2015 Oppenheimer Lecture "Universe or Multiverse was presented by Andrei Linde on Monday, February 23. The lecture was held in the Chevron Auditorium at International House. See pictures of the event here.
Universe or Multiverse
Abstract: Cosmological observations show that the universe is very uniform on the maximally large scale accessible to our telescopes. The best theoretical explanation of this uniformity is provided by the inflationary theory. I will briefly describe the status of this theory in view of recent observational data obtained by the Planck satellite. Rather paradoxically, this theory predicts that on a very large scale, much greater than what we can see now, the world may look totally different. Instead of being a single spherically symmetric balloon, our universe may look like a "multiverse", a collection of many different exponentially large balloons ("universes") with different laws of low-energy physics operating in each of them. The new cosmological paradigm, supported by developments in string theory, changes the standard views on the origin and the global structure of the universe and on our own place in the world.