The University of Columbia proposes to W. Pauli a professorship of physics.

C.-S. Wu writes to F. Pauli about a photograph of W. Pauli and about neutrino.

Letter from H. Reichenbach to W. Pauli, relating to Bohr's inferences.

Article on I. I. Rabi published in The New Yorker

Letter amplifying his cable from the boat to the USA, urging Heisenberg not to publish now and not to send anything off before giving Pauli an opportunity to express his view. He wants Heisenberg's clear reply on the degeneration of the vacuum, mirror states, the metric in Hilbert space and the eigenvalue problem. He gives more details about the last point. He writes about reactions of colleagues (also Bohr) in New York to their ideas. The scepticism of Yang and Lee and of Heisenberg's pupils, has made Pauli feel that publication should be deferred.

Pauli writes that the crucial question for the spinor model is whether a reasonable formulation of an eigenvalue problem can be found for the masses of the particles. He talks about a special question concerning interaction in quantum mechanics: do products of field operators for the same point have a well defined meaning? He does not accept Källén's arguments against the spinor model.