English

The Non-Commutative $A_1$ $T$-system and its positive Laurent property

Quantum Algebra 2015-06-18 v2 Statistical Mechanics Mathematical Physics Combinatorics math.MP

Abstract

We define a non-commutative version of the A1A_1 T-system, which underlies frieze patterns of the integer plane. This system has discrete conserved quantities and has a particular reduction to the known non-commutative Q-system for A1A_1. We solve the system by generalizing the flat GL2GL_2 connection method used in the commuting case to a 2×\times2 flat matrix connection with non-commutative entries. This allows to prove the non-commutative positive Laurent phenomenon for the solutions when expressed in terms of admissible initial data. These are rephrased as partition functions of paths with non-commutative weights on networks, and alternatively of dimer configurations with non-commutative weights on ladder graphs made of chains of squares and hexagons.

Keywords

Cite

@article{arxiv.1402.2851,
  title  = {The Non-Commutative $A_1$ $T$-system and its positive Laurent property},
  author = {P. Di Francesco},
  journal= {arXiv preprint arXiv:1402.2851},
  year   = {2015}
}

Comments

21 pages, 35 figures, minor changes