Physics Fall 2024 Colloquium: Revealing the nonlinearity of the quantum vacuum with high-intensity laser fields

Antonino Di Piazza, University of Rochester

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Antonino Di Piazza

When

3 – 4 p.m., Sept. 27, 2024

Where

Abstract: The British mathematician Ian Stewart wrote in his book The great mathematical problems that “...you can tell how advanced a physical theory is by the number of interacting bodies that it can’t handle. Newton’s law of gravity runs into problems with three bodies. General relativity has difficulty dealing with two bodies. Quantum theory is over-extended for one body, and quantum field theory runs into trouble with no bodies - the vacuum.”

One of the most striking predictions of already the simplest quantum field theory, quantum electrodynamics (QED), as compared to classical physics is that the vacuum in the presence of a background electromagnetic field behaves like a nonlinear dielectric medium.

I will first introduce how the vacuum is described within QED and how, according to this theory, it features nonlinear dielectric properties in the presence of a background electromagnetic field. After making examples of QED processes due to such a vacuum nonlinearity, I will conclude discussing experimental efforts to detect some of these processes mostly at present and already planned high-intensity laser facilities.

3:00 PM in PAS 201 / Zoom Meeting https://arizona.zoom.us/j/81283840289

Refreshments in PAS 218, 2:30PM
 

Contacts

Johann Rafelski