Oppenheimer Lecture: Alan Guth Talks Cosmic Inflation And The Multiverse

Alan Guth will deliver the J. Robert Oppenheimer Memorial Lecture Monday. Courtesy photo

By ROGER SNODGRASS
Los Alamos Daily Post

Alan Guth is not just one of the leading cosmologists in the world; he is widely viewed as a rock star cosmologist in a time of revolutionary advances. The distinguished Victor F. Weisskopf Professor of Physics at the Massachusetts Institute of Technology, Guth is best known for his leading role in developing the theory of inflationary cosmology.

In 1979, he had what he labeled in a note to himself, a “spectacular realization” about the birth of the universe. Since then he continues to refine a cosmological foundation that can account for observable phenomena from the early universe that cannot otherwise be explained.

On Monday July 27, at 7:30 p.m., in  Duane Smith Auditorium, Guth will deliver the 45th annual J. Robert Oppenheimer Memorial Lecture. The free talk, entitled, “Inflationary Cosmology: Is Our Universe Part of a Multiverse?” is sponsored by the J. Robert Oppenheimer Memorial Committee, which will also present scholarships to 13 students from Northern New Mexico at that time.

In a telephone interview this week, Guth said he planned to discuss the basics of inflation, not only what it is, but what evidence there is to support it. According to the model, inflation caused the universe to expand exponentially in its very early stages and then, when it stopped, released its energy to form a hot soup of ordinary particles that would evolve into the visible universe. 

When Guth talks about very early stages, he means early. Within the framework of inflationary cosmology, he can talk about the history of the universe back to times as early as the tiniest fraction of the first second. Unfortunately, “Even inflation does not take us back to the very beginning,” he points out in a World Science University master class video on cosmology from October 2014. “Inflation tends to hide the evidence of the very beginning because the tremendous expansion dilutes any trace of what the universe might have looked like. A complete explanation would be desirable.”

For Guth the big bang is what happened after inflation. Inflation came first and then the bang followed. But that’s not all there is to it.

After introducing inflation, Guth plans to provide some of the evidence for inflation from the perspective of cosmological problems that inflation solves, by examining the properties of our universe that inflation helps explain. The cosmic microwave background radiation discovered 50 years ago, which has been studied in elaborate detail since then, reveals a strikingly regular pattern across the far reaches of the known universe.  This is hard to explain without the rapid, virtually simultaneous expansion attributed to inflation, because the early universe flew apart so fast the different pieces did not have a chance to communicate with each other. How could the microwave background be the same temperature everywhere, near or far?

Finally, Guth will take up some of the extended implications of inflation, especially the idea of the multiverse. How do multiple universes form? Can there be an overlap or a crash of universes?

“I’ll talk about how inflation does not necessarily rigorously imply, but it does suggest that our universe is very likely a part of a larger universe; and that is because almost all inflationary models, almost all detailed versions of inflation, have the property that once inflation starts it never stops completely.” Guth said. “It stops in places and where inflation stops another universe will form, and we call those pocket universes.”

Beyond the pocket universes, space and time continue producing more and more of these pocket universes and we are living in one of them, he added.

Guth has been awarded the Franklin Medal for Physics, the Eddington Medal, the Isaac Newton Medal, the Dirac Prize and the Gruber Prize in Cosmology and has been elected to the U.S. National Academy of Sciences. In 2014, he won the $1 million Kavli Prize in Astrophysics, shared with Andrei Linde of Stanford University and Alexei Starobinsky of the Landau Institute for Theoretical Physics in Russia. The three scientists were cited by the Kavli Foundation “for pioneering the theory of cosmic inflation.”

In 2012, he was one of nine inaugural winners of a $3 million Fundamental Physics Prize by the Milner Foundation, based in Russia, which cited Guth “for the invention of inflationary cosmology, and for his contributions to the theory for the generation of cosmological density fluctuations arising from quantum fluctuations in the early universe, and for his ongoing work on the problem of defining probabilities in eternally inflating space times.”

The Oppenheimer Memorial Committee lecture series began in 1972 with a talk by George F. Kennan. Last year, Harold Varmus, who recently stepped down as Director of the National Institute of Health’s National Cancer Institute, was the speaker. The occasion continues to be one of the most important cultural events of the year in Los Alamos.

The J. Robert Oppenheimer Committee is a philanthropic, non-profit organization dedicated to preserving the memory and legacy of Oppenheimer.

IF YOU GO:

  • Alan Guth: “Inflationary Cosmology: Is Our Universe Part of a Multiverse?
  • 7:30 p.m. Monday, July 27
  • Duane W. Smith Auditorium,
  • 1300 Diamond Dr. in Los Alamos.
CSTsiteisloaded