▁born ▁ 8 ▁November ▁ 1 9 3 9 ) ▁is ▁a ▁theoretical ▁phys ic ist ▁and ▁Di rac ▁Med all ist . ▁Born ▁in ▁Lub lin iec , ▁Poland ▁in ▁ 1 9 3 9 ▁to ▁a ▁Ukrain ian ▁family , ▁the ▁family ▁later ▁moved ▁to ▁Austria ▁and ▁Germany ▁before ▁sett ling ▁in ▁New ▁York ▁City ▁when ▁Jack iw ▁was ▁about ▁ 1 0 . ▁ ▁Biography ▁Jack iw ▁earned ▁his ▁under grad uate ▁degree ▁from ▁Sw arth more ▁College ▁and ▁his ▁Ph D ▁from ▁Corn ell ▁University ▁in ▁ 1 9 6 6 ▁under ▁Hans ▁Bet he ▁and ▁Kenneth ▁Wilson . ▁He ▁was ▁a ▁professor ▁at ▁the ▁Massachusetts ▁Institute ▁of ▁Technology ▁Center ▁for ▁The oret ical ▁Physics ▁from ▁ 1 9 6 9 ▁until ▁his ▁ret irement . ▁He ▁still ▁retain s ▁his ▁affili ation ▁in ▁emer it us ▁status ▁in ▁ 2 0 1 9 . ▁ ▁Jack iw ▁co - dis cover ed ▁the ▁ch iral ▁anom aly , ▁which ▁is ▁also ▁known ▁as ▁the ▁Ad ler – B ell – Jack iw ▁anom aly . ▁In ▁ 1 9 6 9 , ▁he ▁and ▁John ▁Stewart ▁Bell ▁published ▁their ▁explanation , ▁which ▁was ▁later ▁expanded ▁and ▁clar ified ▁by ▁Stephen ▁L . ▁Ad ler , ▁of ▁the ▁observed ▁decay ▁of ▁a ▁neutral ▁p ion ▁into ▁two ▁phot ons . ▁This ▁decay ▁is ▁forb idden ▁by ▁a ▁symmetry ▁of ▁classical ▁elect rod ynam ics , ▁but ▁Bell ▁and ▁Jack iw ▁showed ▁that ▁this ▁symmetry ▁cannot ▁be ▁preserved ▁at ▁the