Last week, I was shocked to learn of the unexpected death of Tim Cochran, a topologist from my grad school alma mater, Rice University. In addition to being a well-respected mathematician, he was an advocate for women and other underrepresented groups in mathematics and a beloved advisor to his many students. Since hearing the news, many of my friends have posted their remembrances of Tim, and it is clear that he cared about helping his students and colleagues find their way not only mathematically but also personally. Daniel Moskovich wrote a post about knot concordance in memory of Tim on the Low Dimensional Topology blog. It’s hard for me to imagine the Rice math department without him.

In the rest of this article, I am collecting posts about some of the other mathematicians who passed away this year.

Alexander Grothendieck, who passed away on November 13 at the age of 86, was the most famous mathematician who died this year. The combination of his profound mathematical brilliance and his political activism and eventual withdrawal from society made him a legendary figure in mathematics. David Bruce and Peter Woit were two of the first English-language bloggers to write about Grothendieck’s passing, with short posts containing links to other information about him. Steve Landsburg also wrote two posts about Grothendieck and his mathematics shortly after his death, and Ken Regan’s tribute is a blend of biography, philosophy, and mathematics. Grothendieck was known for making the mathematics he worked on as general and abstract as possible, and his work is quite difficult for even other mathematicians to understand. Recently, David Mumford posted an obituary he and John Tate wrote for *Nature* that attempted to describe not only the man but also some of his math; however, the article was deemed too technical for *Nature*, and it was rejected.

Lee Lorch passed away this February at 98. Like Grothendieck a politically active mathematician, he remained in society and worked for desegregation in several different communities where he lived. He taught many of the first African Americans to earn PhDs in math. Unfortunately, some of the institutions where he worked—and the House Committee on Un-American Activities—did not appreciate his activism, and he was pushed out of several jobs in the US before getting a post at the University of Alberta and eventually settling at York University in Toronto. York science librarian John Dupuis has a remembrance of Lorcho that includes links to other information about the remarkable man. JoAnne Growney also wrote a post on her math poetry blog in memory of Lorch. It concludes with “The Locus of a Point,” a lovely poem by Lillian Morrison.

Italian math educator Emma Castelnuovo passed away in April at age 100. I have only been able to find posts about her in Italian, but the IMU recently named an award for “outstanding achievements in the practice of mathematics education” after her.

Ken Regan and Dick Lipton wrote touching remembrances of mathematician Ann Yasuhara and computer scientist Susan Horowitz, both of whom died on June 11th. Like all their posts, these articles do an excellent job of telling us about both the people and their work.

I learned about Dame Kathleen Ollerenshaw, mathematician and politician, in 2012, the year she turned 100. Sadly, she passed away in August at 101. I found her story very moving. She dealt with some very difficult circumstances but seemed to be resilient and optimistic through it all. Her autobiography, written at age 93, describes someone who never stopped being curious.

UCLA mathematician Geoff Mess also passed away in August. Danny Calegari remembered him with a post about groups quasi-isometric to planes, the subject of one of Mess’s most important papers.

If you have written or know of a blog post about a mathematician I have neglected to include, please share it. If you would like to learn more about mathematicians who have passed away recently, the AMS maintains an “in memory of…” page.

Longtime Princeton math professor Ed Nelson passed away this year. He made important contributions to statistical physics as well as set theory and foundations. He was also a great teacher.

An obituary is here: http://www.princeton.edu/main/news/archive/S41/11/36I14/index.xml?section=topstories

Nice to remember these people although sad that they are gone. James Stewart, author of a calculus book that many of us have taught from, died Dec 3.

theglobeandmail.com/news/toronto/james-stewart-devoted-his-life-to-math-and-music/article22168574/

Prof. Robert F. McNaughton(RPI) , (a student Prof. W. Quine and Prof. Hao Wong) passed away on June 5th 2014. He worked on infinite games, mathematical logic, regular expressions, Algebraic Automata Theory, Thue Systems and Scheduling Algorithms.

You can find an obituary in English of Emma Castelnuovo here:

http://www.mathunion.org/pipermail/icmi-news/2014-July/000031.html