We are deeply saddened to announce to the mathematics community that Franz Halter-Koch passed away on November 29, 2023. Below is an obituary written by Scott T. Chapman and Alfred Geroldinger.
“Franz Halter-Koch began his study of mathematics and physics at the University of Graz in 1962. Some years later, he moved to the University of Hamburg, where he completed his master thesis under the supervision of Helmut Hasse. He then returned to the University of Graz and wrote his PhD thesis under the supervision of the number theorist Alexander Aigner. After positions at the Graz University of Technology and at the University of Cologne, he became a professor at the University of Essen in 1973. He moved back to Graz in 1981, where he served as a professor at the University of Graz and as the head of the algebra and number theory group until his retirement in 2008.
Franz Halter-Koch made substantial contributions to classical elementary and algebraic num- ber theory, to commutative algebra in rings and monoids, and to factorization theory. He wrote about 150 research papers and 6 monographs, including the books Ideal Systems, Non-Unique Factorizations, and Class Field Theory and L-Functions. He was a member of several mathematical societies as well as the Austrian Academy of Sciences.
Not only his academic work, but his passion for mathematics and his selfless support inspired his local group in Graz as well as many colleagues in the worldwide community. We are grateful that we had him as a teacher and mentor over these many decades.
Our thoughts are with his wife Dorothea, his children Christian, Beate, and Anna, and his seven grandchildren.
A longer obituary will appear in a forthcoming issue of the International Mathematical News of the Austrian Mathematical Society.”