Tutte polynomials and bicycle dimension of ternary matroids
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- by François Jaeger PDF
- Proc. Amer. Math. Soc. 107 (1989), 17-25 Request permission
Abstract:
Let $M$ be a ternary matroid, $t\left ( {M,x,y} \right )$ be its Tutte polynomial and $d\left ( M \right )$ be the dimension of the bicycle space of any representation of $M$ over ${\text {GF}}\left ( 3 \right )$. We show that, for $j = {e^{2i\pi /3}}$, the modulus of the complex number $t\left ( {M,j,{j^2}} \right )$ is equal to ${\left ( {\sqrt 3 } \right )^{d\left ( M \right )}}$. The proof relies on the study of the weight enumerator ${W_\mathcal {C}}\left ( y \right )$ of the cycle space $\mathcal {C}$ of a representation of $M$ over ${\text {GF}}\left ( 3 \right )$ evaluated at $y = j$. The main tool is the concept of principal quadripartition of $\mathcal {C}$ which allows a precise analysis of the evolution of the relevant invariants under deletion and contraction of elements. Soit $M$ un matroïde ternaire, $t\left ( {M,x,y} \right )$ son polynôme de Tutte et $d\left ( M \right )$ la dimension de l’espace des bicycles d’une représentation quelconque de $M$ sur ${\text {GF}}\left ( 3 \right )$. Nous montrons que, pour $j = {e^{2i\pi /3}}$, le module du nombre complexe $t\left ( {M,j,{j^2}} \right )$ est égal à ${\left ( {\sqrt 3 } \right )^{d\left ( M \right )}}$. La preuve s’appuie sur l’étude de l’énumérateur de poids ${W_\mathcal {C}}\left ( y \right )$ de l’espace des cycles $\mathcal {C}$ d’une représentation de $M$ sur ${\text {GF}}\left ( 3 \right )$ pour la valeur $y = j$. L’outil essentiel est le concept de quadripartition principale de $\mathcal {C}$ qui permet une analyse précise de l’évolution des invariants concernés relativement à la suppression ou contraction d’éléments.References
- Thomas H. Brylawski, A decomposition for combinatorial geometries, Trans. Amer. Math. Soc. 171 (1972), 235–282. MR 309764, DOI 10.1090/S0002-9947-1972-0309764-6 T. H. Brylawski and D. Lucas, Uniquely representable combinatorial geometries, Proc. of Int. Colloq. in Combinatorial Theory, Rome, Italy, 1973; Atti Dei Convegni Lincei 17, Tomo 1 (1976), 83-104.
- Henry H. Crapo, The Tutte polynomial, Aequationes Math. 3 (1969), 211–229. MR 262095, DOI 10.1007/BF01817442
- Curtis Greene, Weight enumeration and the geometry of linear codes, Studies in Appl. Math. 55 (1976), no. 2, 119–128. MR 447020, DOI 10.1002/sapm1976552119
- Louis H. Kauffman, New invariants in the theory of knots, Amer. Math. Monthly 95 (1988), no. 3, 195–242. MR 935433, DOI 10.2307/2323625
- W. B. R. Lickorish and K. C. Millett, Some evaluations of link polynomials, Comment. Math. Helv. 61 (1986), no. 3, 349–359. MR 860127, DOI 10.1007/BF02621920 M. J. MacWilliams and N. J. A. Sloane, The theory of error-correcting codes, North-Holland, Amsterdam, New York, Oxford, 1978.
- P. Rosenstiehl and R. C. Read, On the principal edge tripartition of a graph, Ann. Discrete Math. 3 (1978), 195–226. MR 505877
- Morwen B. Thistlethwaite, A spanning tree expansion of the Jones polynomial, Topology 26 (1987), no. 3, 297–309. MR 899051, DOI 10.1016/0040-9383(87)90003-6
- W. T. Tutte, A ring in graph theory, Proc. Cambridge Philos. Soc. 43 (1947), 26–40. MR 18406, DOI 10.1017/s0305004100023173
- W. T. Tutte, A contribution to the theory of chromatic polynomials, Canad. J. Math. 6 (1954), 80–91. MR 61366, DOI 10.4153/cjm-1954-010-9
- D. J. A. Welsh, Matroid theory, L. M. S. Monographs, No. 8, Academic Press [Harcourt Brace Jovanovich, Publishers], London-New York, 1976. MR 0427112
Additional Information
- © Copyright 1989 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 107 (1989), 17-25
- MSC: Primary 05B35
- DOI: https://doi.org/10.1090/S0002-9939-1989-0979049-1
- MathSciNet review: 979049