Making Errors

Abstract

Pauli described Källén’s remarkable speed in doing computations, his reliability and capacity to quickly spot errors in articles by others. Here are some of Pauli’s comments.

To Gustafson:

I wish to thank you very much that you have sent to me Dr. Källén, who turned out to have great skill and talent. He is working both very quickly and [is] very reliable.

To Heisenberg:

If you wish to get an answer from letters to Copenhagen, I give you the practical advice not to write to Møller or Glaser but to write to Källén. To wit, he gladly writes long letters (especially when he believes he can prove you wrong, which is almost always the case).

Concerning making error, the distinguished Austrian theoretical physicist Walter Thirring in his autobiographical book writes (translated from German):

His [Källén’s] scientific brilliance was beyond any doubt. In computations he never made any errors. In another area, however, he did once commit an error, namely as airplane pilot, an error that one does not commit a second time.

Källén’s correspondence shows that he considered work by Thirring, which was usually sent to him by Pauli to scrutinize, as “sloppy”, because sometimes he would find errors in them. Pauli, had to admit that Källén had “won the bet”, as he put it. The error was exactly where he had spotted it. But that was OK. After all it was a matter of circulating articles before publication and errors could be corrected. Thirring would never give up and indeed ended up making lasting contributions to mathematical physics.