Claudio Baiocchi

{{Short description|Italian mathematician (1940–2020)}}

Claudio Baiocchi (August 20, 1940 – December 14, 2020) was an Italian mathematician. He was a professor at the University of Pavia and since the 1990s he was a professor of mathematical higher analysis at the Sapienza University.

He worked on partial differential equations and the calculus of variations. In 1971 he applied his mathematical methods to a free boundary problem in the filtration of liquids through porous media with applications in civil engineering (by using the Baiocchi transform).{{cite journal|author=Baiocchi, C.|title=Sur un problème à frontière libre traduisant le filtrage de liquides à travers des milieux poreux|journal=C. R. Acad. Sci. Paris|volume=273|year=1971|pages=1215–1217}}{{cite journal|author=Baiocchi, C.|title=Sur un problema di frontiera libera connesso a questioni di idraulica|journal=Ann. Mat. Pura Appl.|volume=92|issue=4|year=1972|pages=107–127|doi=10.1007/BF02417940 |s2cid=122863538 |doi-access=free}}{{cite journal|author=Baiocchi, C.|author2=Comincioli, V.|author3=Magenes, E.|author4=Pozzi, G.A.|title=Free boundary problems in the theory of the fluid through porous media: existence and uniqueness theorems|journal=Ann. Mat. Pura Appl.|volume=96|issue=4|year=1973|pages=1–82|doi=10.1007/BF02414909 |s2cid=119934268 }}

His later research dealt with, among other topics, the Collatz problem,{{cite journal|author=Baiocchi, C.|author2=Morgenstern, Maurice|title=Cellular automata about the 3x+1 problem|journal=Proc. LCCS 2001|publisher=University of Paris}} cellular automata and Turing machines.Three small universal Turing machines, in: Machines, computations and universality, LN computer science 2055, Springer 2011, 1–10

In 1970 Baiocchi received the Caccioppoli Prize. In 1974 he was an invited speaker at the International Congress of Mathematicians in Vancouver. He was elected to the Accademia dei XL{{Cite web |url=http://www.accademiaxl.it/it/accademia/soci/soci-nazionali.html |title=Member list of the Accademia Nazionale della Scienze detta dei XL |access-date=2015-09-30 |archive-url=https://web.archive.org/web/20151001111436/http://www.accademiaxl.it/it/accademia/soci/soci-nazionali.html |archive-date=2015-10-01 |url-status=dead }} and the Accademia dei Lincei.