### Mathematician Martin Davis passed away Jan. 1 at the age of 94.

#### 'Warm, kind, intellectually brilliant'

Though publicly recognized as a curious trailblazer in computability and logic, Davis is cherished by his friends and family as a kind and joyful companion, world traveler, aesthete, dancer and giver.

"He was a warm, kind, intellectually brilliant man, with interests across the gamut of human experience,"said Martin Davis's son Harold Davis.

As a mathematician, Davis was most famously known for his work on Hilbert's tenth problem, a mathematical problem posed by David Hilbert in 1900. Davis's work on the problem, along with contributions made by Julia Robinson and Hilary Putnam, allowed mathematician Yuri Matiyasevich, who later became a friend, to eventually solve the problem in 1970.

Davis was also a champion in computability theory. His book Computability and Unsolvability published in 1958 is a classic for students of computer science, said Liesbeth De Mol.

Davis was also uniquely involved in the academic world of logic, in addition to the practical world of the first computers. He received his undergraduate degree from New York City College and pursued his PhD at Princeton University, where he met mathematicians Emil Post and Alan Turing, respectively. Furthermore, Davis developed a model of the Post-Turing machine to anchor the work of both mathematicians.

"He was not by any means a typical mathematician,"said former professor of mathematics at Oxford University Andrew Hodges, who met Davis through his writing on Turing. "He was a very individual, very clearly spoken, very forthright and self-motivated person who really opened up new fields and new ways of thinking."

De Mol also noted Davis's humility, adding that he was a kind person who stood for justice and equality.

"He stood up for me during my public defense,"said De Mol in an email. "I learned that there are two kinds of people in academia and I was lucky enough to have met someone like Martin Davis when still a Ph.D. student."

Davis helped many young scientists and mathematicians and was a devoted husband and father to two kids, according to Harold, who described his "rich childhood"filled with museum visits in Europe and computer programming, noting his father's willingness to share his intellectual side.

Davis was also very close to his wife Virginia who died hours after he did, according to Harold. The two traveled together, went zydeco dancing and hosted dinners for friends and family.

Davis prided himself on being his wife's art assistant, according to friend and professor of mathematics at Wesleyan Carol Wood, who described the pair as "two halves of a whole."

Davis chose to retire in Berkeley because he believed it became the center of symbolic logic, according to friend and computer scientist Alvy Smith. Furthermore, he was active in campus's logic and methodology of science department and was known for his colloquium talks.

"He always chose very interesting topics, often connecting his life and the science and mathematics he'd done,"said UC Berkeley mathematics professor Thomas Scanlon. "He opened a window to a time all of us who are much younger haven't experienced, like his time working at Princeton on the first computers."

January 28, 2023 © Daily Californian