My Father’s Theorem

"The Rockmore theorem made its first—and perhaps only—named appearance in print in 1977, in the journal Physics Letters, Volume 72B, No. 4. A photocopy of the journal page hung on my father’s office door, at Rutgers University, in New Jersey. The author of the article—one B. L. Birbrair, of the Academy of Sciences of the U.S.S.R.—wrote that, in 1959, my dad had demonstrated that the “interaction between quasiparticles exactly compensates” for “the difference between the effective and real mass” of an “infinite non-superfluid fermi system.” Since then, he went on, “the statement J(Δ = 0) = J_rig” has been known as “the Rockmore theorem.”

My dad had underlined those last three words in bold, black pen. Other professors on the same hallway displayed conference posters on their doors, in which they were featured as keynote speakers in exotic locales. My dad couldn’t produce such a poster, but the photocopy, which hung amid New Yorker cartoons, preprints, and departmental announcements, showed something arguably more valuable."