The quantum-number positivity conjecture for quantum dilogarithm factorisations

Let QQ be the quiver with two vertices 0,10,1, no loops, and kZ1k\in\mathbb{Z}_{\geq 1} arrows from 00 to 11. For nZ1n\in\mathbb{Z}_{\geq 1}, define the signed quantum numbers

[±n]q=(1)n+1qn/2qn/2q1/2q1/2.[\pm n]_q=(-1)^{n+1}\frac{q^{n/2}-q^{-n/2}}{q^{1/2}-q^{-1/2}}.

Using the quantum torus variables with multiplication TdTd=(q1/2)d,dQTd+dT^{\mathbf d}T^{\mathbf d'}=(-q^{1/2})^{-\langle\mathbf d',\mathbf d”\rangle_Q}T^{\mathbf d+\mathbf d'}, write

E([±n1]qT(0,1))E([±n2]qT(1,0))=θE(gθ),\mathbb{E}([\pm n_1]_qT^{(0,1)})\mathbb{E}([\pm n_2]_qT^{(1,0)})=\prod_{\infty\xrightarrow{\theta}-\infty}\mathbb{E}(g_\theta),

where gθ=d1/d2=θgd1,d2(q1/2)T(d1,d2)g_\theta=\sum_{d_1/d_2=\theta}g_{d_1,d_2}(q^{1/2})T^{(d_1,d_2)}. Quantum-number positivity conjecture. For every n1,n2,kZ1n_1,n_2,k\in\mathbb{Z}_{\geq 1}, each coefficient gd1,d2(q1/2)g_{d_1,d_2}(q^{1/2}) is a sum of elements of {[±n]qn1}\{[\pm n]_q\mid n\geq1\}. This is a proposed Lefschetz-type positivity property for quantum theta-function factorisations.

Sources & referencesView supporting material

Primary source

Ben Davison, “BPS cohomology in geometry and representation theory”, arXiv:2601.08004 (2026).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.