The 2026 Robert Hofstadter Memorial Lecture: Professor Marek Karliner- "The Social Life of Subatomic Particles"

Please mark your calendars for the 2026 Hofstadter Memorial Lecture on Monday, May 4th at 7:30pm! This year's speaker is Professor Marek Karliner. Marek Karliner is an emeritus professor of physics at Tel Aviv University (TAU).

Abstract: The various materials that we experience in everyday life are built from molecules. In turn, molecules are built from atoms. Atoms are built from electrons and nuclei. Nuclei are built from protons and neutrons, which were once considered “elementary particles”. Bob Hofstadter won his Nobel Prize for dispelling this notion by showing that protons have an internal structure and measuring their size. I will describe how, building on his work, we learned that protons and neutrons are built from particles called quarks and gluons. As far as we know, this is where the “cosmic onion” ends. However, we have also discovered that quarks come in six different flavors and that they have a rich “social life”: they are never alone and always appear in clusters that correspond to protons, neutrons and their numerous cousins. In recent years experiments in giant particle accelerators have dramatically advanced our understanding of the "social preferences" of quarks, revealing many exotic clusters and determining which ones are stable enough to be observed experimentally and how quarks are arranged inside them.

Following the Hofstadter Lecture, Professor Karliner will also speak at the Tuesday, May 5th Physics/AP Colloquium at 3:30. As always, both lectures are free and open to the public. 

The Robert Hofstadter Memorial Lecture Series were established in 1993 by the Stanford Physics Department. Each year, an eminent speaker is invited to give an evening public lecture followed by an afternoon colloquium.