Cosmological observations show that the universe is very uniform on the largest scales accessible to our telescopes, and the same laws of physics operate in all of its parts that we can see now. The best theoretical explanation of this uniformity is provided by the inflationary theory, proposed 30 years ago. 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 extremely large scales, 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 physics operating in each of them. In the beginning, this picture looked more like a piece of science fiction than a scientific theory. However, recent developments in inflationary cosmology, particle physics, and string theory provide strong evidence supporting this new cosmological paradigm. This is a profound challenge to the standard views on the origin and the global structure of the universe and on our own place in the world.

About the speaker
Andrei Linde (Stanford University) is one of the inventors of the theory of chaotic inflation, the most general form of inflationary cosmology, that provides our best current understanding of the origins and distribution of stars and galaxies in our universe. He is the author of the books Inflation and Quantum Cosmology and Particle Physics and Inflationary Cosmology. His honors include the Dirac Medal, Peter Gruber Prize, the Fundamental Physics Prize, and Kavli Prize. Together with Prof. Renata Kallosh he is a guest professor at the Institute Lorentz for Theoretical Physics for the summer of 2017.

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This lecture will be in English.