Gábor Hetyei

Department of Mathematics and Statistics
335 Fretwell
University of North Carolina at Charlotte
Charlotte NC 28223-0001
    Phone: (704) 687-2543
Fax: (704) 687-6415
E-mail: ghetyei@uncc.edu

Research Interests

Combinatorics, commutative algebra, and complexity theory.

Professional experience

University of North Carolina, Charlotte (08/00-present)
Assistant professor (08/00-06/06), associate professor (07/06-present).
University of Kansas (8/97-06/00)
Term assistant professor.
Mathematical Sciences Research Institute (9/96-6/97)
Postdoctoral Fellow participating in the special year in Combinatorics.
Université du Québec à Montréal (8/94-8/96)
Postdoctoral Fellow at the Laboratoire de Combinatoire et d'Informatique Mathématiques.
Postdoctoral Fellowship from the UQAM Foundation (8/94-8/95).
Massachusetts Institute of Technology (9/90-5/94)
Research Assistant 1/93-5/93 and 9/91-1/92 for Prof. Richard P. Stanley.

Education

Massachusetts Institute of Technology (9/90-5/94)
PhD in Mathematics (May 27, 1994).
Thesis title: Simplicial and Cubical Complexes: Analogies and Differences.
Thesis supervisor: Prof. Richard P. Stanley.
MIT Applied Mathematics Program Fellowship (9/90-5/91 and 1/92-5/92).
Mittag-Leffler Institute (4/92-5/92)
Visitor at the conference year on combinatorics, with a stipend from the Mittag-Leffler Institute.
Florida Atlantic University (1/90-7/90)
Graduate student (advisor: Prof. Heinrich Niederhausen).
Mathematical Institute of the Hungarian Academy of Sciences (9/89-12/89)
Graduate student (advisor: Prof. Richárd Wiegandt).
École Normale Supérieure (Paris) (10/88-7/89)
Visiting Student (advisor: Prof. Bernard Teissier).
Eötvös University Budapest (12/83-7/88)
Master of Science (with honors) in Mathematics (July 6, 1988, thesis advisor: László Székely).
Major field: Algebra (supervised by Prof. Richárd Wiegandt).
Minor field: Computer Science (supervised by Prof. László Babai).

Personal Data

Hungarian citizen. Member of the American Mathematical Society and of the Bolyai János Mathematical Society.

Prizes, Awards and Grants

Practical skills

English, French, German, and Hungarian spoken fluently, reading knowledge of Russian.
Familiar with Maple, TeX, LaTeX and HTML.

Teaching experience

University of North Carolina, Charlotte (09/00-present)
Lecturer for the following classes:
Undergraduate: Business Calculus (Fall '00 and '06), College Algebra (Spring '00 and '02-'06 and Fall '02-'06), Combinatorics (Spring '03), Finite Mathematics (Spring '02), Graph Theory (Fall '01, '03, '05), Modern Algebra (Fall '00, Spring '01).
Advanced undergraduate or graduate: Calculus from an Advanced Viewpoint (Spring '05), Foundations of Real Analysis (Fall '04), Modern Algebra (Fall '02), Non-Euclidean Geometry (Spring '06), Number Theory (Spring '02 and Fall '03).
Duties: Teaching the classes, supervising my assistants, authoring common finals.
University of Kansas (8/97-06/00)
Lecturer for the following undergraduate classes:
Calculus II (Fall 97, Fall 98 (two sections), Spring 99, Fall 99), Intermediate Logic (Spring 99 and Fall 99), Mathematics of Engineering Systems (Spring 98, in collaboration with Thomas E. Glavinich from the Architectural Engineering Department), Mathematical Foundations of Computer Science (Fall 97), Ordinary Differential Equations (Summer 99).
Duties: Teaching the classes and supervising the work of my graders.
Université du Québec à Montréal (9/95-12/95)
Lecturer for the undergraduate class Algèbre matricielle (linear algebra, Fall 95).
Duties: Teaching the class, supervising a recitation instructor and a grader.
Massachusetts Institute of Technology (1/91-5/91, 9/92-1/93, 9/93-1/94 and 1/94-5/94)
Teaching Assistant for the graduate classes Introduction to Stochastic Processes (for Prof. Gian-Carlo Rota, Spring 94) and Combinatorial Theory (for Prof. Richard P. Stanley, Fall 93, and for Prof. Gian-Carlo Rota, Fall 92).
Duties: Grading homework, holding office hours, supervising the preparation of lecture notes for Introduction to Stochastic Processes, preparing lecture notes for Rota's Combinatorial Theory.
Part Time Teaching Assistant for the undergraduate class Introduction to Algorithms (for Prof. C. E. Leiserson, Spring 91).
Duties: Grading homework, preparing sample solutions. (Some of which appeared in the "Instructor's Manual" by Julie Sussman to the book "Introduction to algorithms" by Thomas H. Cormen, Charles E. Leiserson and Ronald L. Rivest.)
Florida Atlantic University (1/90-7/90)
Teaching Assistant for the undergraduate classes College Algebra (Spring 90) and Number Theory (Summer 90, both for Prof. M.J. DeLeon).
Duties: Grading homework, holding office hours.

Publications

In refereed journals
  1. "On ordering the free product of ordered semigroups," Annales Univ. Sci. Budapestiensis De Rolando Eötvös Nominatae, Tomus XXXII (1989), 233-241.
  2. "On the diameter of random Cayley graphs of the symmetric group," Combinatorics, Probability & Computing 1 (1992), 201-208 (with L. Babai).
  3. "Generalizations of Baxter's theorem and cubical homology,", Journal of Combinatorial Theory A 69 (1995), 233-287 (with R. Ehrenborg).
  4. "On the Stanley ring of a cubical complex," Discrete & Computational Geometry 14 (1995), 305-330.
  5. "On the cd-variation polynomials of André and simsun permutations," Discrete & Computational Geometry 16 (1996), 259-276.
  6. "Invariants des complexes cubiques," Annales des Sciences Mathématiques du Québec 20 (1996), 35-52.
  7. "Permutation trees and variation statistics," European Journal of Combinatorics 19 (1998), 847-866 (with E. Reiner).
  8. "Cubical Species and Nonassociative Algebras," Advances in Applied Mathematics 21 (1998), 499-546 (with Pierre Leroux and Gilbert Labelle).
  9. "Linear inequalities for flags in graded partially ordered sets," Journal of Combinatorial Theory A 89 (2000), 77-104 (with L. Billera).
  10. "Flags and shellings of Eulerian cubical posets," Annals of Combinatorics 4 (2000), 199-226 (with R. Ehrenborg).
  11. "Decompositions of partially ordered sets," Order 17 (2000), 141-166 (with L. Billera).
  12. "Flag vectors of Eulerian partially ordered sets," European Journal of Combinatorics 22 (2001), 5-26 (with M. Bayer).
  13. "Graphs and Balanced Simplicial Complexes," Graphs and Combinatorics 18 (2002), 533-564.
  14. "Generalizations of Eulerian partially ordered sets, flag numbers and the Möbius function," Discrete Mathematics 256 (2002), 577-593 (with M. Bayer).
  15. "Tchebyshev posets," Discrete & Computational Geometry 32 (2004), 493-520.
  16. "Matrices of formal power series associated to binomial posets," Journal of Algebraic Combinatorics 22 (2005) 65-104.
  17. "Orthogonal polynomials represented by CW-spheres," Electronic Journal of Combinatorics, Vol 11(2) #R4.
  18. "Polyspherical Complexes," Annals of Combinatorics 9 (2005) 379 - 409.
  19. "Central Delannoy numbers and balanced Cohen-Macaulay complexes," Annals of Combinatorics 10 (2006) 443-462.
  20. "The topology of the independence complex," European Journal of Combinatorics 27 (2006), 906-923. (with R. Ehrenborg).
  21. "The Stirling polynomial of a simplicial complex," Discrete & Computational Geometry 35 (2006), 437-455.
  22. "Tchebyshev triangulations of stable simplicial complexes," Journal of Combinatorial Theory A 115 (2008) 569-592.
  23. "Tutte Polynomials of Tensor Products of Signed Graphs and their Applications in Knot Theory" preprint 2007, to appear in Journal of Knot Theory and Its Ramifications.
 
In conference proceedings
  1. "On the diameter of finite groups," Proc. 31st IEEE Symp. on Foundations of Computer Science, St. Louis MO (1990), 857-865 (with L. Babai, W.M. Kantor, A. Lubotsky, Á. Seress).
  2. "The cd-index of Eulerian cubical posets," Proceedings of the 7th international conference on "Formal Power Series and Algebraic Combinatorics", Paris, May 29-June 2, 1995 (with R. Ehrenborg).
  3. "Invariants of cubical spheres," Proceedings of the 8th international conference on "Formal Power Series and Algebraic Combinatorics", Minneapolis, June 24-June 29, 1996.
  4. "Permutation trees and variation statistics," Proceedings of the 9th international conference on ``Formal Power Series and Algebraic Combinatorics'', Vienna, July 14-18, 1997 (with E. Reiner).
  5. "Tutte polynomials of signed graphs and Jones polynomials of some large knots", Proceedings of the International Workshop on Knot Theory for Scientific Objects held in Osaka, March 8-10, 2006, Editor Akio Kawauchi. Osaka Municipal University Press. 1-16 (2007) (with Y. Diao and K. Hinson).
 
Technical reports and other
  1. "Generalization of a problem of the mathematical olympiad," ("Egy olimpiai feladat általánosítása," in Hungarian) Mathematical Journal for Secondary Schools (KöMaL) 34 (1984), 102-107.
  2. "Anneaux de Cohen-Macaulay définis par des matroïdes", ("Cohen-Macaulay rings defined by matroids,") Mathematical Institute of the Hungarian Academy of Sciences, preprint no. 47/1989.
 
 
 

Talks

  1. "Edge-orientable cubical polytopes and a conjecture of Eisenbud, Green, and Harris,", MIT Combinatorics Seminar, March 2, 1994.
  2. "On André permutations," LACIM Combinatorics Seminar, September 8, 1994.
  3. "The diameter of random Cayley-graphs of the symmetric group,", LACIM Theoretical Computer Science Seminar, January 26, 1995.
  4. "The cd-index of Eulerian cubical posets," 7th international conference on "Formal Power Series and Algebraic Combinatorics" Paris, June 2, 1995.
  5. "Invariants of cubical complexes," LACIM Combinatorics Seminar, October 20, 1995.
  6. "H-vectors of cubical polytopes," Cornell University Mathematics Department, May 23, 1996.
  7. "Invariants of cubical spheres," 8th international conference on "Formal Power Series and Algebraic Combinatorics," Minneapolis, June 25, 1995. (Poster presentation.)
  8. "Permutation trees and variation statistics," Enumeration and Partially Ordered Sets Workshop, MSRI, October 18, 1996.
  9. "Counting Faces of Polyhedral Complexes," University of Illinois at Urbana-Champaign Mathematics Department, January 29, 1997.
  10. "The Linear Inequalities on Flag f-vectors of Ranked Posets," MSRI Combinatorics Seminar, June 4, 1997.
  11. "Permutation trees and variation statistics," 9th international conference on ``Formal Power Series and Algebraic Combinatorics'', Vienna, July 14, 1997. (Poster presentation.)
  12. "Enumeration in ranked posets," workshop on Combinatorial Convexity and Algebraic Geometry, Mathematisches Forschungsinstitut Oberwolfach, October 29, 1997.
  13. "Decompositions of partially ordered sets," Spring Southeastern Sectional Meeting of the AMS, Louisville, KY, March 20, 1998.
  14. "Graphical generalizations of the sieve formula," Spring Southeastern Sectional Meeting of the AMS, Gainesville, FL, March 12-13, 1999.
  15. "Generalized shellings for balanced simplicial complexes," Combinatorics Seminar, University of Pennsylvania, March 23, 1999.
  16. "Linear inequalities for flag numbers in graded partially ordered sets," Combinatorics Seminar, Institute for Advanced Study, Princeton, March 24, 1999.
  17. "Linear inequalities for flag numbers in graded, planar and Eulerian posets," The 8th Mathematical Society of Japan International Research Institute Conference on Computational Commutative Algebra and Combinatorics, Osaka University, Toyonaka Campus, Osaka, July 21-30, 1999.
  18. "Generalized shellings for balanced simplicial complexes," Combinatorics Seminar, Texas A & M University, September 20, 1999.
  19. "Inequalities for Eulerian posets via doubling," LaCIM 2000 Conference, Montréal, September 8, 2000.
  20. "Flag numbers of generalized Eulerian posets," Fall Western Sectional Meeting of the AMS, San Francisco, CA, October 21-22, 2000.
  21. "The l-vector of general and balanced simplicial complexes," workshop on Combinatorial Convexity and Algebraic Geometry, Mathematisches Forschungsinstitut Oberwolfach, January 12, 2001.
  22. "Meaning and uses of the l-vector," Spring Central Sectional Meeting of the AMS, Lawrence, KS, March 30-31, 2001.
  23. "Decomposing the order complex of graded partially ordered sets," Colloquium talk at the University of Florida Mathematics Department October 29, 2001.
  24. "The quest for the cubical analogue of the simplicial h-vector," Combinatorics Seminar at the University of Florida Mathematics Department, October 30, 2001.
  25. "Linear inequalities for classes of partially ordered sets," Colloquium talk at the University of Kentucky Mathematics Department, November 8, 2001.
  26. "Counting chains in graded partially ordered sets," Colloquium talk at the University of South Carolina Mathematics Department, March 5, 2002.
  27. "The topology of the independence complex," Spring Central Sectional Meeting of the AMS, Ann Arbor, MI, March 1-3, 2002.
  28. "Orthogonal polynomials represented by CW-spheres," "Retrospectives in Combinatorics", Conference in the Honor of Richard Stanley's 60-th birthday, MIT, June 22-26, 2004.
  29. "The s-vector and the reemergence of the diamond product," Algebraic Combinatorics Seminar at the University of Kentucky Mathematics Department, February 11, 2005.
  30. "The s-vector of a simplicial complex," 6th Combinatexas conference, Texas State University, San Marcos TX, February 26, 2005.
  31. "Central Delannoy numbers, Jacobi polynomials, and a new operation on balanced simplicial complexes," Combinatorics Seminar, University of South Carolina, March 22, 2005.
  32. "Central Delannoy numbers, Legendre polyomials, and a balanced join operation preserving the Cohen-Macaulay property," 18th international conference on ``Formal Power Series and Algebraic Combinatorics'', San Diego, CA, June 23, 2006.
  33. "Tutte polynomials of tensor products of colored graphs," Fall Southeastern Meeting of the AMS, Murfreesboro, TN, November 3, 2007.
  34. "Bernoulli type games and combinatorial enumeration," Fall Southeastern Meeting of the AMS, Murfreesboro, TN, November 4, 2007.
  35. "Links We Almost Missed Between Delannoy Numbers and Legendre Polynomials", Billerafest 2008, Cornell University, Ithaca, NY, June 15, 2008.

Conferences and meetings organized

  1. Special session on Algebraic and Extremal Combinatorics for the AMS 2007 Spring Southeastern Section Meeting. (with László Székely).

References

  1. Prof. László Babai, Department of Computer Science, University of Chicago, Chicago, IL 60637.
  2. Prof. Margaret Bayer, Department of Mathematics, University of Kansas, 405 Snow Hall, 1460 Jayhawk Blvd, Lawrence, KS 66045-7523.
  3. Prof. Louis J. Billera, Department of Mathematics,501 Malott Hall, Cornell University, Ithaca, NY 14853-4201.
  4. Prof. Dan Kleitman, Department of Mathematics, MIT, Cambridge, MA 02139-4307.
  5. † Prof. Pierre Leroux, LACIM, Université du Québec à Montréal, C.P. 8888, succ. Centre-Ville, Montréal (Québec) Canada H3C 3P8.
  6. Prof. Richard P. Stanley, Department of Mathematics, MIT, Cambridge, MA 02139-4307.
  7. Prof. Bernard Teissier, Université Paris 7, Institut mathématique de Jussieu, 175 Rue du Chevaleret, 75013 Paris, France.

Last update: Friday, June 20, 2008.