A Solution Space for a System of Null-State Partial Differential Equations: Part 4

作者:Flores Steven M*; Kleban Peter
来源:Communications in Mathematical Physics, 2015, 333(2): 669-715.
DOI:10.1007/s00220-014-2180-0

摘要

This article is the last of four that completely and rigorously characterize a solution space S-N for a homogeneous system of 2N + 3 linear partial differential equations in 2N variables that arises in conformal field theory (CFT) and multiple Schramm-Lowner evolution (SLE kappa). The system comprises 2N null-state equations and three conformal Ward identities that govern CFT correlation functions of 2N one-leg boundary operators. In the first two articles (Flores and Kleban in Commun Math Phys, 2012; Flores and Kleban, in Commun Math Phys, 2014), we use methods of analysis and linear algebra to prove that dim S-N <= C-N, with C-N the Nth Catalan number. Using these results in the third article (Flores and Kleban, in Commun Math Phys, 2013), we prove that dim S-N = C-N and S-N is spanned by (real-valued) solutions constructed with the Coulomb gas (contour integral) formalism of CFT. In this article, we use these results to prove some facts concerning the solution space S-N. First, we show that each of its elements equals a sum of at most two distinct Frobenius series in powers of the difference between two adjacent points (unless 8/kappa is odd, in which case a logarithmic term may appear). This establishes an important element in the operator product expansion for one-leg boundary operators, assumed in CFT. We also identify particular elements of S-N, which we call connectivity weights, and exploit their special properties to conjecture a formula for the probability that the curves of a multiple-SLE kappa process join in a particular connectivity. This leads to new formulas for crossing probabilities of critical lattice models inside polygons with a free/fixed side-alternating boundary condition, which we derive in Flores et al. (Partition functions and crossing probabilities for critical systems inside polygons, in preparation). Finally, we propose a reason for why the exceptional speeds [certain kappa values that appeared in the analysis of the Coulomb gas solutions in Flores and Kleban (Commun Math Phys, 2013)] and the minimal models of CFT are connected.

  • 出版日期2015-1