Planar flows and quadratic relations over semirings
DOI: 10.1007/s10801-012-0344-6
Abstract
Adapting Lindström's well-known construction, we consider a wide class of functions which are generated by flows in a planar acyclic directed graph whose vertices (or edges) take weights in an arbitrary commutative semiring. We give a combinatorial description for the set of “universal” quadratic relations valid for such functions. Their specializations to particular semirings involve plenty of known quadratic relations for minors of matrices (e.g., Plücker relations) and the tropical counterparts of such relations. Also some applications and related topics are discussed.
Pages: 441–474
Keywords: plücker relation; dodgson condensation; tropicalization; semiring; planar graph; network flow; lindström's lemma; Schur function; Laurent phenomenon
Full Text: PDF
References
35. Cambridge University Press, Cambridge (1997) Gessel, I.M., Viennot, X.: Determinants, paths, and plane partitions. Preprint (1989) Lindström, B.: On the vector representation of induced matroids. Bull. Lond. Math. Soc. 5, 85-90 (1973) CrossRef Miller, E., Sturmfels, B.: Combinatorial Commutative Algebra. Graduate Text in Mathematics, vol.
227. Springer, Berlin (2005) Postnikov, A.: Total positivity, Grassmannians, and networks. arXiv:math.CO/0609764 (2006) Talaska, K.: A formula for Plücker coordinates associated with a planar network. arXiv:0801.4822 [math.CO] (2008)