As of June 1, 2019, I am retired! Information below is valid up to that time. A few things are updated.
I am the Williams Professor of Mathematics in the Department of Mathematics and Statistics at the University of Vermont in the great state of Vermont. I was the Department Chair for the Math Department from 1998 — 2004 and I was also the Interim Chair of the Department of Computer Science at UVM from 2010–2012. The photo to the left was taken in February 2009 at Alpine Meadows Ski Area. That’s Lake Tahoe in the background. To see the photo of me that was on this site from 1984 until 2000 click here.
My old address, phone and fax number is given below.
My mathematical interests
I am interested in computational and algebraic methods for determining the structure and existence of combinatorial configurations, such as designs and graphs. I am also interested in applications of combinatorial configurations to computer science and information theory and the design and analysis of combinatorial algorithms to find designs or label graphs.
I am the co editor-in-chief of the CRC Handbook of Combinatorial Designs (with Charlie Colbourn) and I maintain the web pages for the Handbook. Check it out. Click here for a photo of Charlie and me taken in Colorado in 1995 when we first showed a preliminary manuscript of the Handbook to people at the R.C. Bose Conference in Fort Collins. We are holding up the title page of the book.
From 2005 until 2014, I was the co-director (with Sheila Weaver) of the Governor’s Institute in Mathematical Sciences. This is a one week program for mathematically talented high school students. There was a nice article in the Burlington Free Press on June 26, 2008 about the Institute and another Free Press article on June 26, 2009.
In 2001, my colleague Dalibor Froncek and I were involved with the now defunct football league, the XFL. No, they didn’t need me to be a player. We actually constructed the schedule of play for their 2001 season. Too bad the league folded after one year, they really liked our schedule and were planning on working with us again. At least we got to go to the championship game in Los Angeles and we got a lot of press for doing the schedule. Here is a photo of me and Dalibor in the LA Coliseum at the Championship game. The New York Times published a story about our scheduling the XFL, it appeared on Feb 3, 2001. (I saved it locally — click here if you do not subscribe to the NY times online.) A similar article appeared in the sports page of the Burlington Free Press on Feb 11, 2001. The NYT article has been translated into Estonian by Sonja Kulmala, if that interests you – click here.
In some circles, I am most well-known for posing the so called “Dinitz Conjecture”. I made this conjecture to Paul Erdos in 1979 and it was eventually proven by Fred Galvin of the University of Kansas in 1994.
My other interests
I have a wife Sue and three grown kids, Mike , Amy, and Tom . Sue is retired now but formerly taught in the English Department at the University of Vermont and was the longtime head of the UVM Writing Center. Mike is an Associate Professor in theoretical computer science at Johns Hopkins University in Baltimore. Amy is a doctor specializing in internal medicine at the University of Vermont Medical Center and Tom got his Ph.D in mathematics at The Ohio State University (Go Bucks!) and now has a job as a data scientist at Klaviyo in Boston.
I enjoy sporting activities such as skiing, biking, sailing, kayaking, and hiking. I sail every Wednesday night in the summer as a member of the crew on my friend Mark’s J-30 sailboat. We do pretty well☺ My favorite ski area is Mad River Glen where I’m a shareholder. Here is a web page about how volunteers help maintain the famous woods trails at Mad River.
I was the faculty advisor to the UVM club football team since it’s inception in 2007 until I retired.– Go Cats Go.
I am also a huge Ohio State Buckeyes football fan. (National Champions 2002 !! BCS finalist 2006 and 2007, undefeated 2012! National Champions 2014!!!) Click here or here for the latest information about the Buckeyes football team.
I also like my tractor. It’s a 1974 Ford and I use it to plow snow in the winter and to mow the lawn in the summer. I have a few photos of me plowing my driveway during the snowy winter of 2000-2001. Click here or here to see the photos. Update: the tractor died in December 2015 🙁 . I now have a new snowblower.
I have scanned in some pictures. Here is an index of the photos (not updated in a while).
- My publications (includes links to all my referereed journal publications).
- My vita
- My close friend and colleague Dan Archdeacon passed away in February 2015. Here is the eulogy I gave for Dan at the memorial service.
- Vermont Rhythms – this is a Tom Johnson composition that uses a result on Room squares that was found by me and my MS student Susan Janiszewski. Check it out – it is pretty cool!
- My favorite new song — gotta love latin squares!! This was recorded in July 2011 and is a Tom Johnson composition titled “Squares”. (Be sure to listen around the 5:00 mark). It is performed by Andrew McIntosh.
- In March 2018, I gave one of the invited talks at the 49th Southeastern Conference on Combinatorics, Graph Theory and Computing at Florida Atlantic University in Boca Raton, Florida. Here are the slides for that talk which was titled “The construction and uses of Heffter arrays”.
- In June 2011, I gave one of the invited talks at the 2nd Istanbul Design Theory, Graph Theory and Combinatorics Conference held at Koc University in Istanbul, Turkey. Here are the slides for the talk which was titled “Some constructions for replication pemutation arrays”.
- I gave one of the invited talks at the 29th Midwestern Conference on Combinatorics, Cryptography, and Computing held in Rochester, NY in October 2009. This conference was honoring Wal Wallis. Here are the powerpoint slides for the talk.
- I was named a University Scholar for 2008-2009. Click here to see a cool poster announcing my award. I gave my University Scholar Lecture on April 15 2009. Here are the powerpoint slides for the talk.
- I was interviewed on the tv show Across the Fence shown on WCAX-TV on June 8, 2008. I discusssed topics such as: my teaching philosophy, what people can do with a math degree, how to make a round robin-tournament, my scheduling of the XFL and the Governors Institute for Mathematical Sciences. I think it went pretty well. You can click here for the video (can be played using quicktime).
- I visited Ghana in April 2004 and I presented a series of lectures. Click here for the slides from these lectures.
- I was an invited speaker at a conference held in a castle in Germany in April 2005. The conference was called Algebraic Combinatorics and Applications (ALCOMA05). Click here for the conference website — including lots of photos.
- I was also one of only 9 foreign invited speaker at a conference held in Tehran, Iran in April 2006. I had a great time there! The conference was sponsored by the Institute for Studies in Theoretical Physics and mathematics (IPM). Click here for the conference website — again including lots of photos.
- My MS student, Patty Fogarty investigated firefighting on grids. Here is her thesis. Click here for the instructions for the java applet and here for the applet.
- The current weather in Burlington.
Department of Mathematics and Statistics
University of Vermont
16 Colchester Ave.
Burlington, Vermont 05405
My office was in 206 Mansfield House.
Telephone: 656-4292 (not any more)
Fax: (802) 656-2552
Back to the Math page: Click here.