Who is Alexander Vilenkin?
Alexander Vilenkin is a theoretical physicist, whose research and work is focused on inflationary models, cosmic strings and quantum cosmology.
Alexander Vilenkin was born in Kharkiv in the former Soviet Union in 1949 and immigrated to the United States in 1976, where he completed his Ph.D. at SUNY Buffalo. After a year as a postdoc at Case Western Reserve University, he joined the faculty of Tufts University where he is currently L. and J. Bernstein Professor of Evolutionary Science. Alexander Vilenkin also serves as Director of the Tufts Institute of Cosmology. Dr. Vilenkin is a fellow of the American Physical Society and a member of the National Academy of Sciences.
Alexander Vilenkin and Eternal Inflation Theory
Alexander Vilenkin showed that cosmic inflation, a period of rapid and accelerated expansion in the early universe, likely continues eternally in other regions of the universe.
Alexander Vilenkin also worked with Arvind Borde and Alan Guth to develop the Borde–Guth–Vilenkin theorem, which states that “any universe that has, on average, been expanding throughout its history cannot be infinite in the past but must have a past spacetime boundary.” (Wikipedia)
In this video, Alexander Vilenkin refutes three eternal models (i.e., Eternal Inflation, Cyclic Evolution, and Static Seed (Emergent Universe)) that posit a universe without a beginning (i.e., eternal into the past). He then offers his rationale (via the Borde- Guth- Vilenkin Theorem) for a beginning.
Alexander Vilenkin: What Happened Before Inflation?
How did the universe come into existence? Theories like the Big Bang and Eternal Inflation lead us to ask, “What happened before these events? And what happened before what happened before?” One possibility is that the universe was spontaneously created out of nothing. Some would argue that this is purely a philosophical or theological perspective, but in this video from Toe Movie, Alexander Vilenkin describes a possible solution based on physics and mathematics.
“It is a great mystery of how this tunneling of the universe happens. And the mystery is that the same laws of physics that describe evolution of the universe…describe this quantum creation of the universe.” —Alexander Vilenkin