in physics in 1975, completing his senior thesis, titled "Broken symmetry of the Pseudoscalar Yukawa theory", under the supervision of Arthur S.

While still a graduate student, Preskill made a name for himself by publishing a paper on the cosmological production of superheavy magnetic monopoles in Grand Unified Theories.

Since we do not observe any magnetic monopoles, this work pointed out serious flaws in the then current cosmological models, a problem which was later addressed by Alan Guth and others by proposing the idea of cosmic inflation.

[5] Preskill has achieved some notoriety in the popular press as party to a number of bets involving fellow theoretical physicists Stephen Hawking and Kip Thorne.

Preskill was elected as a Fellow of the American Physical Society in 1991 and a member of the National Academy of Sciences in 2014.