Research Interests

Algebraic combinatorics is my research area, with the focus on Jones pairs, type-II matrices and their relations to association schemes. Association schemes encode combinatorial objects such as distance regular graphs and symmetric designs. They can also be viewed as a generalization of finite abelian groups. Two families of association schemes, the Johnson schemes and the Hamming schemes, have applications in the study of designs, codes and orthogonal arrays. My interest lies in the connections of association schemes with coding theory, design theory, graph theory and knot theory.
I am also interested in algebraic graph theory, quantum walks on graphs and complex Hadamard matrices.

Publications/Preprints

• Ada Chan, Chris Godsil, Christino Tamon, Weichen Xie, Of shadows and gaps in spatial search, arXiv:2204.04355.
• Ada Chan, Gabriel Coutinho, Whitney Drazen, Or Eisenberg, Chris Godsil, Mark Kempton, Gabor Lippner, Christino Tamon, Hanmeng Zhan, Fundamentals of fractional revival in graphs, arXiv:2004.01129, submitted.
• Ada Chan, Complex Hadamard matrices and strongly regular graphs, arXiv:1102.5601.
  
• Ada Chan and Hanmeng Zhan, Pretty good state transfer in discrete-time quantum walk, arXiv:2105.03762.


• Ada Chan, Bobae Johnson, Mengzhen Liu, Malena Schmidt, Zhanghan Yin, Hanmeng Zhan, Laplacian pretty good fractional revival, Discrete Math. 345 (2022), no. 10, Paper No. 112971.
• Ada Chan, Bobae Johnson, Mengzhen Liu, Malena Schmidt, Zhanghan Yin, Hanmeng Zhan, Laplacian fractional revival, Electronic Journal of Combinatorics 28 (2021), no.3, Paper No. 3.22.
• Ada Chan, Whitney Drazen, Or Eisenberg, Mark Kempton, Gabor Lippner, Pretty good quantum fractional revival in paths and cycles, Algebraic Combinatorics 4 (2021), no.6, 989-1004.
• Ada Chan, Shaun Fallat, Jephian Lin, Steve Kirkland, Shahla Nasserasr, Sarah Plosker, Complex Hadamard diagonalizable graphs. Linear Algebra and its Applications 605 (2020), 158--179.
  
• Ada Chan, Complex Hadamard matrices, instantaneous uniform mixing, and cubes, Algebraic Combinatorics 3 (2020), no.3, 757--774.
  
• Ada Chan, Gabriel Coutinho, Christino Tamon, Luc Vinet, Harmony Zhan, Fractional revival and association schemes, Discrete Math. 343 (2020), no. 11.
  
• Ada Chan, Gabriel Coutinho, Christino Tamon, Luc Vinet, Harmony Zhan, Quantum fractional revival on graphs, Discrete Applied Mathematics 269 (2019), 86--98.
  
• Pierre Antoine Bernard, Ada Chan, Erika Loranger, Christino Tamon, Luc Vinet, A graph with fractional revival. Physics Letters A, 382 (2018) Issue 5, 259--264.
  
• Ethan Ackelsberg, Zachary Brehm, Ada Chan, Joshua Mundinger and Christino Tamon, Adjacency State Transfer in Coronas, Electronic Journal of Combinatorics, 24 (2017), 2--24.
  
• Ethan Ackelsberg, Zachary Brehm, Ada Chan, Joshua Mundinger and Christino Tamon, Laplacian State Transfer in Coronas, Linear Algebra and its Applications, 506 (2016), 154--167.
  
• Ada Chan and A. Munemasa, Hamming graph in Nomura algebra, Linear algebra and its applications 435 (2011), no. 2, 330--341.
  
• Ada Chan and C. D. Godsil, Type-II matrices and combinatorial structures, Combinatorica 30(2010), no. 1, 1--24.
  
• Ada Chan and Rie Hosoya, On the association schemes of type-II matrices constructed on conference graphs, J. Algebraic Combinatorics 20 (2004), no. 3, 341--351.
  
• Ada Chan and C. D. Godsil, Bose-Mesner algebras attached to invertible Jones pairs, J. Combin. Th. Ser. A 106 (2004), no. 2, 165--191.
  
• Ada Chan, C. D. Godsil, and A. Munemasa, Four-weight spin models and Jones pairs, Trans. Amer. Math. Soc. 355 (2003), no. 6, 2305-2325 (electronic).
  
• Ada Chan and R. M. Wilson, Some consequences of the linear programming bounds for designs, University of Waterloo Research Report CORR 2001-36 , 2001
  


• Ada Chan, Jones pairs, Ph.D. Thesis, University of Waterloo, 2001
  
• Ada Chan, Bounds on designs derived from Delsarte's inequalities, Master Thesis, University of Waterloo, 1995
  

Seminars

• Mathematics and Statistics Colloquium
  University of Regina, Canada, April 2022
  
• Western Canada Linear Algebra Meeting (online)
  Brandon University, Canada, June 2021
  
• Algebraic graph theory seminar (online)
  University of Waterloo, Canada, January 2021
  
• Virtual seminar
  Winnipeg Institute of Theoretical Physics, Canada, August 2020
  
• Discrete Mathematics Seminar
  Worcester Polytechnic Institute, USA, February 2020
  
• Joint Algebraic Combinatorics and Algebraic Graph Theory Seminar
  University of Waterloo, Canada, February 2020
  
• Session on Special Functions and Orthogonal Polynomials
  AMS 2019 Fall Central Sectional Meeting, University of Wisconsin-Madison, USA, September 2019
  
• Session on Association Schemes and Related Topics
  AMS 2019 Fall Central Sectional Meeting, University of Wisconsin - Madison, USA, September 2019
  
• Prairie Discrete Mathematics Workshop
  Brandon University, Canada, June 2018
  
• Algebraic Graph Theory and Quantum Walks Workshop
  University of Waterloo, Canada, April 2018
  
• Session on Extremal Graph Theory and Quantum Walks on Graphs
  AMS 2018 Spring Eastern Sectional Meeting, Northeastern University, USA, April 2018
  
• Session on Algebraic Graph Theory
  CMS 2017 Winter Meeting, Waterloo, Canada, December 2017
  
• Session on Matrix Theory
  CMS 2016 Winter Meeting, Niagara Falls, Canada, December 2016
  
• Systems of Lines: Application of Algebraic Combinatorics
  Worcester Polytechnic Institute, USA, August 2015
  
• Discrete Math Day in the Northeast
  Bard College, USA, March 2015
  
• Graphs at Ryerson Seminar
  Department of Mathematics, Ryerson University, Canada, October 2014
  
• Potsdam Research Experience for Undergraduates in Mathematics
  Department of Mathemtics, SUNY Potsdam, USA, July 2014
  
• Discrete Math Seminar
  Department of Mathematics and Statistics, York University, Canada, February 2014
  
• Algebraic Combinatorics Seminar
  Dept. of Combinatorics and Optimization, University of Waterloo, Canada, March 2013
  
• Session on Combinatorics
  CMS 2012 Spring Meeting, Regina, Canada, June 2012
  
• Ottawa-Carleton Discrete Mathematics Day
  Carleton University, March 2012
  
• Workshop on Algebraic Graph Theory
  BIRS, Banff, Canada, April 2011
  
• Applied Algebra Seminar
  Department of Mathematics and Statistics, York University, Canada, April 2010
  
• Session on Combinatorics
  CMS 2008 Winter Meeting, Ottawa, Canada, December 2008
  
• Special Session on Association Schemes and related topics
  AMS 2005 Fall Central Meeting, University of Nebraska - Lincoln, U.S.A., October 2005
  
• Algebraic Combinatorics Seminar, University of Waterloo, Canada, April 2005
  
• Algebraic Combinatorics Seminar, University of Waterloo, Canada, November 2005
  
• Information Mathematical Sciences Colloquium, Tohoku University, Japan, July 2004
  
• Combinatorics Seminar, University of Wisconsin-Madison, U.S.A., November 2003
  
• Special Session on Association Schemes: 1973-2003
  2003 AMS Fall Southeastern Section Meeting, University of North Carolina at Chapel Hill, U.S.A., October 2003
  
• Special Session on Association Schemes and Distance Regular Graphs
  2002 AMS Spring Western Section Meeting, Portland State University, U.S.A., June 2002
  
• Kyushu University, Japan, May 2002
  
• Applied Algebra Seminar, York University, Canada, April, 2002
  
• Combinatorics Seminar, California Institute of Technology, U.S.A., February 2001
  
• Faculty of Mathematics Graduate Student Conference, University of Waterloo, Canada, June 2000
  
• Management Science Seminar, Tilburg University, Netherlands, September 1998
  
• Algebraic Combinatorics Day, University of Toronto, Canada, July 1998
  
• Eleventh Ontario Combinatorics Workshop, Ryerson University, Canada, May 1997