Bilinear relation for generic q-deformed conformal blocks

Let q1,q2,u,Zq_1,q_2,u,Z satisfy q2<1<q1|q_2|<1<|q_1|. Define

F^d(u,q1,q2Z)=2nZu2dn(q1q2)4dn2Z2n2(uq14n2,u1q14n2)(1)(uq11q24n+1,u1q11q24n+1)(2)Fn(1)(q12dZ)Fn(2)(q22dZ),\widehat{\mathcal{F}}_d(u,q_1,q_2|Z)=\sum_{2n\in\mathbb{Z}}\frac{u^{2dn}(q_1q_2)^{4dn^2}Z^{2n^2}}{(uq_1^{4n-2},u^{-1}q_1^{-4n-2})^{(1)}_\infty(uq_1^{-1}q_2^{4n+1},u^{-1}q_1^{-1}q_2^{-4n+1})^{(2)}_\infty}\mathcal{F}^{(1)}_n(q_1^{2d}Z)\mathcal{F}^{(2)}_n(q_2^{2d}Z),

where

Fn(1)(z)=F(uq14n,q12,q11q2z),Fn(2)(z)=F(uq24n,q1q21,q22z).\mathcal{F}^{(1)}_n(z)=\mathcal{F}(uq_1^{4n},q_1^2,q_1^{-1}q_2|z),\qquad \mathcal{F}^{(2)}_n(z)=\mathcal{F}(uq_2^{4n},q_1q_2^{-1},q_2^2|z).

Also define

F(u,q1,q2Z)=λ1,λ2Zλ1+λ221i,j=12Nλi,λjNS(q1,q2,ui/uj).\mathcal{F}_{\lozenge}(u,q_1,q_2|Z)=\sum_{\lambda_1,\lambda_2}Z^{\frac{|\lambda_1|+|\lambda_2|}{2}}\frac{1}{\prod_{i,j=1}^2N^{\mathrm{NS}}_{\lambda_i,\lambda_j}(q_1,q_2,u_i/u_j)}.

The source defines the factors Nλ,μN^{\lozenge}_{\lambda,\mu} using the subsets of boxes selected by the stated parity condition.

Generic bilinear relation.

F(u,q1,q2Z)=F^1(u,q1,q2Z),F(u,q1,q2Z)=(1q2q1Z1/2)F^0(u,q1,q2Z).\mathcal{F}_{\lozenge}(u,q_1,q_2|Z)=\widehat{\mathcal{F}}_1(u,q_1,q_2|Z),\qquad \mathcal{F}_{\lozenge}(u,q_1,q_2|Z)=(1-q_2q_1Z^{1/2})\widehat{\mathcal{F}}_0(u,q_1,q_2|Z).

This extends the bilinear relations from q1=q1q_1=q^{-1} and q2=qq_2=q to generic parameters in the indicated sector; the supplied text gives no separate resolution status.

Sources & referencesView supporting material

Primary source

M. A. Bershtein and A. I. Shchechkin, “Q-deformed Painleve tau function and q-deformed conformal blocks”, arXiv:1608.02566 (2019).

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.