David Wehlau

Department of Mathematics and Statistics
Queen's University

 Dept. of Mathematics & Statistics
 Queen's University
 Kingston, Ontario
 Canada  K7L 3N6
Location:      503 Jeffery Hall
 office: (613) 533-2389
 fax:      (613) 533-2964
and  wehlau@mast.queensu.ca


Mathematical Myth:

Contrary to a widely held myth, the loneliest number is, in fact, an irrational number between 7 and 8.



 Both of my late parents were professional astronomers and longtime members of the Department of Astronomy at Western University in London Ontario.  They have both been honoured by having newly discovered asteroids named for them.

My mother, Dr. Amelia Wehlau has had the asteroid 304122 Ameliawehlau named for her.  You can see a description of this asteroid on NASA's website here.  You can see an animation of the
asteroid in its orbit here.

The asteroid 204786 wehlau was has been named after my late father, William Henry Wehlau. You can see a description of the asteroid here and see an animation of its orbital progress here.



Click here for a list of my published research


Current Graduate Students

I currently have three graduate students:
Sonja Ruzic is writing up her dissertation on certain weight modules for super Lie algebras.
Deepanshu Prasad is studying semi-invariants of quiver representations.
 Shan Ren is a visiting Ph.D. student from China studying invariants of p-groups in characteristic p.


Graduated Students

Former students of mine who completed their Ph.D.:
  1. Asia Matthews (2015)
  2. Yinglin Wu (2009)
  3. Emilie Dufrsne (2008)
  4. Sebastian Cioaba (2006)
  5. Jianjum Chuai (2001)
Former students of mine who completed Master's Degrees:
  1. Cody Roth (2022)
  2. Deepanshu Prasad (2020)
  3. Keshia Yap (2020)
  4. Moufit al Mahdi (2020)
  5. Sonja Rucic (2019)
  6. Siqi Li (2019)
  7. Zhen Zhao (2018)
  8. Heather Topping (2017)
  9. Henry de Valance (2015)
  10. Emilie Wheeler (2015)
  11. Sean Zimmerman (2013)
  12. Razan Al_Nakhli (2011)
  13. Daniel Bruce (2007)
  14. Joseph Oldford (2007)
  15. Chester Weatherby (2005)
  16. Letitia Banu (2005)
  17. Emilie Dufresne (2004)
  18. Chris Brav (2003)
  19. Jennifer Vandergraaf (2003)
  20. David Giordano (2000)
  21. Catherine Chambers (1995)
Emilie, Chris and Chester went on to complete Ph.D. degrees at Queen's.

Asia Mathews took a permanent position on the faculty of Quest University in British Columbia.
Yinglin Wu finished his Ph.D. in September 2009 and now works on in IT in Ottawa.
Emilie Dufresne completed her Ph.D. in August 2008. She is now a lecturer in algebra at the University of York in England.
Sebi Cioaba is an Assistant Professor at the Univerity of Deleware.
Jianjun Chuai finished his Ph.D. in August 2003 and was a faculty member at a number of Canadian universities before taking his retirement.

Cody Roth took a job working at the Jet Propulsion Lab for NASA.
Moufid al Mahdi went on to use his expertise to work for the Canadian government in Ottawa.
Keshia Yap wento n to work for TikTok in Singapore
Heather Topping is working as a term professor at the Royal Military College in Kingston.
Sean Zimmerman finshed in August 2013 and then took up a job with Microsoft in Seattle.
Daniel Bruce went on to study Quantitative Finance at the University of Waterloo.
Joe Oldford continued his career officer in the Canadian military.
Chester Weatherby became an assistant Professor at the Wilfrid Laurier University in Waterloo, Ontario.
Chris Brav took up a position as a Post Doctoral Fellow at the Mathematical Institute at Oxford University in the UK.
Letitia Banu and David Giordano both went on to work in Toronto doing financial mathematics for TD Canada Trust.
Jenny Vandergraaf  (now Jenny Waite) took a position working for the United Way in Brockville, Ontario.
Catherine Chambers is now living in Alberta.

PostDoctoral Fellows

I have (co)-supervised a number of postdoctoral fellows.

  1. Dr. K. Nguyen (2023- )
  2. Dr. M. Perlman (2020-2021)
  3. Dr. E. Yildrim (2018-2021)
  4. Dr. B. Nguyen (2017-2019)
  5. Dr. T. Xu (2017-2019)
  6. Dr. D. Rorabaugh (2015-2018)
  7. Dr. F. Galetto (2013-2015)
  8. Dr. A. Hoefel (2011-2014)
  9. Dr. V. Lozovanu (2010-2012)
  10. Dr. J. Thind (209-2011)
  11. Dr. T. Bogart (2007-2010)
  12. Dr. E. Cotterill (2007-2008)
  13. Dr. H Salmasian (2005-2007)
  14. Dr. A. Leface (2005-200)
  15. Dr. J. Harris (2005-2006)
  16. Dr. J. Chuai ( 2003-2005)
  17. Dr. R.J. Shank (1995-1999)
  18. Dr. J. McQuillan (1993-1994)


Past Conferences:

In 2016 I was the principal organizer, aided by H.E.A. Cambell and R.J. Shank, for the conference Algebraic Combinatorics and Group Actions held at Herstmonceux Castle in southern England.

In June 2010 Eddy Campbell, Jianjun Chuai and I co-organized a special session
Group Actions and Their Invariants

at the CMS summer meeting in Fredericton New Brunswick. Click here for a list of speakers and slides from their talks.

I have co-organized two major conferences on algebraic groups.

In July 2006, along with Eddy Campbell, Loek Helminck and Hanspeter Kraft, I organized a conference Symmetry and Spaces; A Conference on the Occasion of Gerry Schwarz's 60th Birthday at the Fields Institute.

In April 2002, Eddy Cambell and I co-organized an invariant theory workshop & conference in connection with the Centre de Recherches Mathématiques' theme year on Groups and Geometry.  


Public Lectures:

I was awarded the 2012 Cowan Prize for Excellence in Research. This is RMC's top reseach prize and the winner gives a public lecture in celebration of the award. Here is the poster advertising my talk, entitled "Quantum Cryptography: An Unbreakable Cipher".

In May 2002 I was awarded the 2001-2002  RMC Class of 1965 Teaching Excellence Award .  One of the honours associated with this award is that I was asked to give a public lecture.  Here you can see the beautiful poster RMC produced advertising the leture.  You can read my notes and see the slides from the lecture entitled "Soldiers, Spies, Crooks: Their Ciphers and Secret Codes ".  


Research Interests:

I am interested in algebraic rings of invariants. These are rings formed by polynomials which have enough symmetry to be left unchanged under the action of some (algebraic) group. One of my main interests is in obtaining degree bounds for homogeneous minimal generating invariants. Such bounds give an algorithm for finding rings of invariants. Here are some conjectures I am interested in proving (or disproving).

I study quivers, quiver representations and representations of algebras in collaboration with my colleague Dr. C. Paquette.

I also study the interconnections between various conditions which guarantee that the ring of invariants are well-behaved. In particular, I am interested in the Popov (or Russian) conjecture. I have worked on this conjecture for quite a while and have proved it for some special cases including for connected abelian groups (tori).

I am also interested in complete caps in finite projective spaces, especially over the binary field. A cap is a set of points with no three points lying on the same line. A cap is complete if adding any another point to it causes it to have three collinear points. Complete caps are closely connected to certain important error correcting codes.

I am also interested in cryptography, both modern public key and other encryption systems and historic cryptography and cryptoanalysis. In the past I did some work for a Calgary company Non-Elephant Encryption . (There is a long story behind the name of the company.)


Previous Experience

I received my Honours Bachelor of Science degree from the University of Western Ontario . My degree is in their Scholars Electives program specializing equally in Mathematics and Computer Science .

I received both my Master of Arts and my Ph.D. from the Department of Mathematics at Brandeis University . My Master's was in Number Theory with Dr. Paul Monsky as my supervisor. My Ph.D. thesis was on Invariant Theory and my supervisor was Dr. Gerald Schwarz .

After leaving Brandeis, I was an Assistant Professor at the University of Toronto in the Department of Mathematics for the period 1988-1992.


My Current Work

I have been in Kingston since the fall of 1992. I work regularly on joint projects with Eddy Campbell and Ivan Dmitrov and Chareles Paquette. who are members of the Queen's math department. In 2004 Eddy moved to Memorial University of Newfoundland where he is the Vice President Academic and the Pro Vice Chancellor. (I always suspected that Eddy was in favour of vice but who knew he could parlay it into a salary?) He is now President of the University of New Brunswick. From 1995 until August 1999 Jim Shank was also at Queen's. In August 1999, Jim left us for the greener pastures (and better choir) at the University of Kent at Canterbury, England. Jim and I are still working together but we now usually use email to conduct our discussions. There are a number of algebraists at Queen's. Among those I work with are Mike Roth, Greg Smith, and Ivan Dmitrov.

The algebraists at Queen's have a whole lot of fun doing research and attending our various seminars (including the algebraic and geometry seminar and the curve seminar).


I am also doing research in the area of Galois geometries and graph theory. Galois geometries are geometries where there are only a finite number of points, lines, planes, etc. Most of this work is with my collaborators Aiden Bruen, Lucien Haddad and Claude Tardif . My research on Galois geometries is concerned with finding maximal line free subsets in geometries over finite fields. I am also studying blocking sets. These are sets which meet every subspace of a given dimension. The study of blocking sets and line free sets yields methods to construct new encryption codes and/or shows that various desired codes cannot exist. In graph theory I am studying properties of colourings of hypergraphs.


I am a professor in the Department of Mathematics at the Royal Military College of Canada (which is a university even though the name makes it sound a little like a college). I do all my undergraduate teaching at RMC. Here I am lecturing on a day when I returned the exam. I am currently teaching two courses: Cryptography and Introduction to Sets and Logic. A few years ago Randy Elzinga typed up the notes for my cryptography course. These contain some typos which I will fix some day when I find the time.

Up until the spring of 2000, I was the coach of the RMC varsity badminton team . You can read all about my activities at RMC on my internal RMC homepage or on my public RMC homepage .


Personal Info

  My wife, daughter and I have two cats.  We live in downtown  Kingston halfwaybetween RMC and Queen's. 


This page is currently under deconstruction. Last deconstructed on December 23, 2023.