Rudolf Haag

Rudolf Haag (17 August 1922 – 5 January 2016) was a German theoretical physicist. He was born in Tübingen, Germany.
Works.
He was best known for his works to the algebraic formulation of axiomatic quantum field theory, namely the Haag-Kastler axioms
, and a central no-go theorem in QFT, Haag's theorem, which demonstrates the nonexistence of a unitary time-evolution operator in the interaction picture.
In 1965 he founded the journal Communications in Mathematical Physics, which he guided as Chief Editor for eight years.
He was awarded the Max Planck medal in 1970 and the Henri Poincaré Prize of the International Association of Mathematical Physics in 1997.
Haag died on 5 January 2016 at the age of 93.