English

Quantum cluster algebra, braid moves and quantum virtual Grothendieck ring

Quantum Algebra 2026-02-06 v2 Representation Theory

Abstract

In this paper, we study the quantum virtual Grothendieck ring, denoted by \frakKq(\g)\frakK_q(\g), which was introduced in [39], and further investigated in [26, 25]. Our approach involves examining this ring from two perspectives: first, by considering its connection to quantum cluster algebras of non-skew-symmetric types; and second, by exploring its relevance to categorification theory. We specifically focus on (i) the homomorphisms that arise from braid moves, particularly 4-moves and 6-moves, in the braid group; and (ii) the quantum Laurent positivity phenomena, which has not yet been proven for non-skew-symmetric types. As applications of our results, we derive the substitution formulas for non-skew-symmetric types discussed in [11] for skew-symmetric types, and demonstrate that any truncated element in a heart subring, denoted by \frakKq,Q(\g)\frakK_{q,Q}(\g), which corresponds to a simple module over the quiver Hecke algebra R\gR^\g, possesses coefficients in Z0[q±1/2]\Z_{\ge 0}[q^{\pm 1/2}]. This result is particularly interesting because it implies that each truncated Kirillov--Reshetikhin polynomial in \frakKq,Q(\g)\frakK_{q,Q}(\g) and each element in the standard basis \sfEq(\g)\sfE_q(\g) of the entire ring \frakKq(\g)\frakK_q(\g) have coefficients also in Z0[q±1/2]\Z_{\ge 0}[q^{\pm 1/2}]. Since (truncated) Kirillov--Reshetikhin polynomials can be obtained using a quantum cluster algebra algorithm and appear as quantum cluster variables, they provide compelling evidence in support of the quantum Laurent positivity conjecture in non-skew-symmetric types.

Keywords

Cite

@article{arxiv.2402.08140,
  title  = {Quantum cluster algebra, braid moves and quantum virtual Grothendieck ring},
  author = {Kyu-Hwan Lee and Se-jin Oh},
  journal= {arXiv preprint arXiv:2402.08140},
  year   = {2026}
}

Comments

This paper is accepted to Selecta Mathematica

R2 v1 2026-06-28T14:46:49.876Z