Peter Casazza

Peter G. Casazza

The Great Peter G. Casazza has passed on. Peter was a groundbreaking mathematician whose generosity, humor, and love of people shaped countless lives. He passed away peacefully at his home in Columbia, MO on October 26, 2025.

Born on June 28, 1945 to Bill Casazza and Brenda Bunting, Peter grew up in East Nassau, New York. Pete earned his Ph.D. in mathematics from the University of Iowa in 1972. Peter went on to work at the University of Alabama-Huntsville as an associate professor of mathematics. In 1977, the National Academy of Science led Peter to spend a year in the U.S.S.R. Peter returned to serve as the department chair of mathematics at the University of Alabama-Huntsville before joining the University of Missouri-Columbia in 1983.

It was in Missouri that Peter met the love of his life, Janet Tremain. Janet, a brilliant mathematician herself, became Pete’s closest collaborator and his constant companion. Working on complex problems with Janet was one of Pete’s great joys, and their shared curiosity and steady devotion shaped every part of the life they built together.

Pete stayed at the University of Missouri until his retirement in 2021. There, he secured millions of dollars in support from the National Science Foundation and held visiting appointments around the world, including at the Hebrew University of Jerusalem in Israel, the University of Cambridge in England, and Odense University in Denmark. He worked in Vienna at the Acoustics Institute, where his research helped advance hearing technologies. Peter delivered more than 400 invited addresses in 35 countries. In 2011, he was named a “Curators’ Distinguished Professor”, one of the University of Missouri’s highest honors.

Peter’s work reshaped modern mathematics. He began his career as a theoretical mathematician and later followed his passion for applied mathematics through collaborations with NASA and other cutting-edge organizations. He published an astonishing number of papers, many of which have been cited hundreds of times. His research covered numerous sub-specialties of mathematics, including Banach and Hilbert space theory, quantum theory, operator theory, applied harmonic analysis, and inverse problems. He is perhaps best known for his pioneering research in developing frame theory. Together with Janet, with whom he collaborated on much of his research, he wrote the widely read ‘The Kadison Singer Problem in Mathematics and Engineering,” a research paper that continues to influence mathematics and many other academic disciplines worldwide.

Pete quite simply made the world a better place. The list of awards Pete received is incredibly lengthy and includes the MU Top Faculty Achiever Award in 2017. Perhaps the best example of his pioneering mathematical advancements resulting in practical applications to our society, is his recognition from the National Science Foundation. In their annual report in 2013, featuring the most significant research they supported, two different sections featured Peter’s work. His work on Phase Retrieval, an area of research introduced by Pete, Radu Balan and Dan Edidin, was cited along with its applications to x-ray crystallography, electron microscopy, diffractive imaging, astronomical imaging, x-ray tomography, etc. In addition, Pete’s work on Fusion Frames, an area of research introduced by Pete and Gitta Kutyniok, was celebrated with its applications to distributed processing and the design of wireless sensor networks for detecting chemical, biological weapons.

Peter was called ‘legendary’ by his peers, and not only for his intellect. His love of teaching and mentoring shaped generations of students, many of whom still refer to him as their greatest advocate and consider him family. He had a way of bringing math to life—mixing rigor with laughter—and he never separated his work from the people who made it meaningful. He believed in seeing the whole person, not just the student, and he took the time to know and help them far beyond the classroom.

Outside of academia, Peter was the kind of person who made life lighter for everyone around him. He hosted lively gatherings, made lifelong friendships, and could make people laugh in the most serious moments, even at math meetings. Pete’s colleagues share that he started an ‘Unsung Heroes’ fund for MU custodial staff. This is a perfect example of Peter’s selflessness and generosity as well as his appreciation and respect for all people. After retiring, he kept teaching—offering self-defense classes to friends and neighbors—and during the pandemic, he and Janet co-wrote a murder mystery titled “Memory” Survival. The second book in the series will soon be released. They never stopped learning or creating together.

Pete’s kindness extended beyond his fellow humans. He and Janet worked for years with the Central Missouri Humane Society, caring for rescued rabbits and even dedicating three rooms of their home to their care. Pete built an outdoor rabbit enclosure at the Humane Society so the animals could live safely and comfortably.

Peter often said, “If it’s worth doing, it’s worth overdoing.” And he lived exactly that way—pushing the boundaries of mathematics, advocating for his students, and giving his time and heart without limit.

Peter is survived by the love of his life Janet Tremain (and her relatives); his son, Perry Casazza; and his brother George Casazza (wife Pam and family). Other surviving family members include stepbrother Andy Swift (wife Linda and family), stepsister Sally Joyce (husband Dan and family), sister-in-law Mary Casazza, first cousin Suzanne Martin (husband John), first cousin John Casazza’s family, niece Amy O’Connor (and children), and nephew Ryan Casazza (wife Alyssa and children). He is survived by a community of students, colleagues, and neighbors who will never forget him. Though Pete will live on forever through his groundbreaking work in mathematics, his greatest legacy is the people he taught, encouraged, and loved.

In lieu of flowers, donations can be made to Peter’s favorite charities:

Central Missouri Humane Society: https://cmhspets.org/donation-form/

Food Bank for Central and Northeast Missouri: https://sharefoodbringhope.org/

Ronald McDonald House: https://secure.qgiv.com/for/ronaldmcdonaldmm/

True North Of Columbia: https://truenorthofcolumbia.org/donate/

To access one of Peter and Janet’s Research Articles, please see below:

Casazza, P.G. and Tremain, J.C. (2006) The Kadison-Singer Problem in Mathematics and Engineering. Proceedings of National Academy of Sciences of the USA, 103, 2032-2039.

https://doi.org/10.1073/pnas.0507888103

To access Peter and Janet’s Murder Mystery, “Memory” Survival, please see below:

https://a.co/d/8b5TcKz