An émi­gré from Nazi Ger­many, Hans Bethe joined Cor­nel­l’s physics depart­ment back in 1935. There, he built a remark­able career for him­self. A nuclear physi­cist, Bethe made key con­tri­bu­tions to the Man­hat­tan Project dur­ing World War II. After the war, he brought stel­lar young physi­cists like Richard Feyn­man from Los Alam­os to Itha­ca and turned Cor­nel­l’s physics depart­ment into a top-notch pro­gram. In 1967, he won the Nobel Prize for “his ground­break­ing work on the the­o­ry of ener­gy pro­duc­tion in stars.”

As a trib­ute to Bethe, Cor­nell now hosts a web site called Quan­tum Physics Made Rel­a­tive­ly Sim­ple, where you can watch three lec­tures pre­sent­ed by Bethe in 1999. They’re a lit­tle dif­fer­ent from the usu­al lec­tures you encounter online. In these videos, Bethe is 93 years old, old­er than your aver­age prof. And he presents the lec­tures not in a Cor­nell class­room, but at the Kendal of Itha­ca retire­ment com­mu­ni­ty, which gives them a cer­tain charm. You can watch them here:

Lec­ture 1: Here Bethe “intro­duces quan­tum the­o­ry as ‘the most impor­tant dis­cov­ery of the twen­ti­eth cen­tu­ry’ and shows that quan­tum the­o­ry gave us ‘under­stand­ing and tech­nol­o­gy.’ He cites com­put­ers as a dra­mat­ic real­iza­tion of applied quan­tum physics.”

Lec­ture 2: “By the 1920s, physi­cists were dri­ving to syn­the­size ear­ly quan­tum ideas into a con­sis­tent the­o­ry. In Lec­ture 2, Pro­fes­sor Bethe relates the excit­ing the­o­ret­i­cal and exper­i­men­tal break­throughs that led to mod­ern quan­tum mechan­ics.”

Lec­ture 3:  In the last lec­ture, “Pro­fes­sor Bethe recalls work on the inter­pre­ta­tion of the wave func­tion, the Heisen­berg Uncer­tain­ty Prin­ci­ple, and the Pauli Exclu­sion Prin­ci­ple. He shows how quan­tum the­o­ry forced dis­cus­sion of issues such as deter­min­ism, phys­i­cal observ­ables, and action-at-a-dis­tance.”

You can watch an intro­duc­tion to the lec­ture series here. You can also find Bethe’s lec­tures list­ed in our col­lec­tion of Free Online Physics Cours­es, part of our col­lec­tion of 825 Free Online Cours­es.

via Kot­tke

Relat­ed Con­tent:

Richard Feyn­man Presents Quan­tum Elec­tro­dy­nam­ics for the Non­Sci­en­tist

‘The Char­ac­ter of Phys­i­cal Law’: Richard Feynman’s Leg­endary Lec­ture Series at Cor­nell, 1964

Leonard Susskind Teach­es You “The The­o­ret­i­cal Min­i­mum” for Under­stand­ing Mod­ern Physics