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Legendary mathematicians: They’re just like us!

Bjarni Jónsson

Bjarni Jónsson, 1920-2016

Sad news via the FOM list today:

Published in Tennessean on Nov. 6, 2016

Bjarni Jónsson, originally of Draghals, Iceland, passed away in Cincinnati, OH on
Friday, September 30, 2016 at the age of 96. Beloved husband of the late Harriet P.
(nee Parkes) Jonsson. Devoted father of Eric (Kaye) Jonsson, Meryl (Bob) Runion Rose
and Kristin (Rick) Porotsky. Loving grandfather of Elisabeth (Terry) Winslow, David
Runion, and Brent, Gena, Aaron, Billy and Cole Porotsky. Former resident of Nashville,
Tennessee. He was Vanderbilt’s first Distinguished Professor of Mathematics. A leader
in his field and author of 89 technical papers, he received many commendations for his
work, including the Earl Sutherland Prize for Academic Research as well as the Knights
Cross awarded by the President of Iceland.

Please send donations in his honor to:

Bjarni Jonsson Research Prize
Department of Mathematics
1326 Stevenson Center
Vanderbilt University
Nashville, TN 37240.

Noted algebraist Bjarni Jónsson dies
by David Salisbury, Oct. 12, 2016
https://news.vanderbilt.edu/2016/10/12/noted-algebraist-bjarni-jonsson-dies/

Bjarni Jónsson, Vanderbilt’s first Distinguished Professor of Mathematics, died Sept.
30 at the age of 96.

Born in Iceland, Jónsson earned his bachelor’s and doctoral degrees from the
University of California-Berkeley and also received an honorary degree from the
University of Iceland. He was internationally recognized as a leading authority on
universal algebra, lattice theory and algebraic logic.

In his career, Jónsson authored 89 technical papers and served on the editorial board
of several major mathematics journals, including Algebra Universalis. He presented
numerous invited talks at mathematics conferences around the world. In 1974, he was an
invited speaker at the International Congress of Mathematicians. In 2012 he was
elected an inaugural fellow of the American Mathematical Society. He was also the
recipient of Vanderbilt’s Harvie Branscomb Distinguished Professor Award in 1974 and
the Earl Sutherland Prize for Achievement in Research in 1982.

“Bjarni Jónsson was a remarkable mathematician who made field-defining and path-
breaking contributions in universal algebra, lattice theory and algebraic logic.
Anyone who had the fortune to know him admired his integrity, kindness and immense
respect for colleagues and friends. His influence on my personal and mathematical life
has been enormous, and it is a great privilege that I have had the opportunity to work
with and learn from him,” said Professor Constantine Tsinakis, a long-term colleague
and a former chair of the mathematics department.

“To me Bjarni will always be a legend, who in his quiet, sincere, unassuming ways
continues to inspire uncountably many algebraists, raising questions and re-examining
areas that he feels would benefit from an algebraic approach,” wrote Peter Jipsen, one
of the doctoral students that Jónsson advised, on the occasion of his 70th birthday.
“While some mathematicians almost revel in stringing together long complex arguments,
Bjarni has constantly sought to simplify and illuminate the subjects dear to him,” the
professor of mathematics at Chapman University added.

Jónsson came to Vanderbilt in 1966 and taught here until his retirement in 1993. When
he arrived, mathematics was mostly an undergraduate teaching department. He was
instrumental in establishing the department’s graduate program, which presently ranks
among the top departments in the nation, according to the latest evaluation by the
National Research Council. Jónsson also formed a research group in algebra that
attracted mathematicians from around the world and contributed substantially to the
high research profile that the department currently enjoys.

Algebra is the study of mathematical objects and the rules for manipulating them.
Jónsson made his most important contributions in the area of universal algebra. It is
one of the most abstract subfields of algebra because it studies algebraic structures
in general, as opposed to specific classes of algebras, such as groups and fields. The
importance of his contributions is reflected by the fact that a number of mathematical
objects are named for him, including Jónsson and Jónsson-Tarski algebras, Jansson
cardinals, Jónsson terms, the Jónsson lemma and the Jónsson-Tarski duality.

During his tenure, Jónsson supervised 14 Ph.D. students. In letters they wrote for a
symposium in honor of his 70th birthday, which took place in Iceland in 1990, his
former students all expressed a deep appreciation for him as a “respected mathematical
guide and personal friend.”

One of the first students he supervised, Steven Monk, now professor emeritus at the
University of Washington, recalled advice that he received from Jónsson regarding
teaching: “Adventure is not in the guidebook and beauty is not on the map. The best
one can hope for is to be able to persuade some people to do some traveling on their
own.”

“Bjarni’s work and scholarly contributions will have a lasting legacy. His name will
forever be interwoven in the history of our department. We are honored to have had
him as a colleague,” noted the current department chair, Professor Mike Neamtu.

[Photo ©Steve Givant]

banff

(SEP ∧ SSHAP) → Calgary

In May 2017, both the Society for Exact Philosophy and the Society for the Study of the History of Analytic Philosophy will hold their annual meetings at the University of Calgary. Come for one, stay for the other, or come for both and stay for Banff National Park in the Canadian Rockies! Keynotes will be given by Juliet Floyd, Robin Jeshion, and Bernie Linsky at SSHAP and Catarina Dutilh Novaes, Louise McNally, and Dorit Ganson at SEP.

 

Immediately before SEP, the Calgary Graduate Student Conference will also be held; the topic will be “Ethics in the Age of Science.” Keynote speakers will be Katrina Sifferd and Gregg Caruso.

screenshot-from-2016-09-26-19-27-01

My First Paper!

I went through old floppies when I went back home over the summer and found the first logic paper I ever wrote! It was on proof theory and general algebra (I guess I must have taken courses in both at the time–1992). For your amusement: A Paedagogical Example of Cut-Elimination

A paedagogical Example of Cut-Elimination

Women Speakers at ASL Meetings

Johanna Franklin has taken on the thankless task of tallying and analyzing the number (and proportion) of female invited speakers at meetings organized by the Association for Symbolic Logic. Her posts are up at the Women in Logic blog:

(The ASL Membership committee received a report in 2009 on this; the data there was a bit more detailed but only covered 2001-09.)

Hao Wang

Interview with Hao Wang and Robin Gandy

In 1991, I videotaped talks at the Kurt Gödel Colloquium in Kirchberg (it was supposed to be held jointly with the Wittgenstein Symposium, that got cancelled). I also videotaped a conversation with Hao Wang and Robin Gandy, students and friends, respectively, of Gödel and Turing.  I can’t for the life of me remember who the interviewer was. Anyway, you may find it interesting:

[Photo credit: San and Jane Wang]

Fall 2016 edition of Sets, Logic, Computation

The Fall 2016 edition of the OLP remix Sets, Logic, Computation is ready. As before, it includes the OLP part on sets, relations, and functions; the part on first-order logic (with natural deduction chosen as the proof system); and the part on Turing computability including the unsolvability of the halting and decision problems. The methods chapter on induction and biographies of Cantor, Church, Gentzen, Gödel, Noether, Russell, Tarski, Turing, and Zermelo appear as appendices. At students’ request, problems are now listed at the end of each chapter. Many typos and errors have been corrected, a number of examples and problems have been added, and several proofs rewritten for clarity. I’ve also added chapter summaries and a glossary. There are also a few added sections, notably introduction sections to Chapters 5 and 7, as well as discussion of Russell’s Paradox in both Chapter 1 and 6. You can order a printed copy on Lulu, or download the PDF from the builds page. SLC F16