Abstract:
We consider the second-order linear differential equation presented in Subsection 4.8 of the paper by J. Dereziński, A. Ishkhanyan, and A. Latosiński [SIGMA 17, 056 (2021)] and called there the deformed double confluent Heun equation. We prove that the additional singular point arising during the construction of the equation does not affect the analytic structure of its solution space. Moreover, we prove that under certain conditions a one-parameter transformation of the equation, called a deformation, with coefficients expressed in terms of the third Painlevé transcendent, leaves its monodromy unchanged. The proofs are self-contained.
Keywords:double confluent Heun equation, deformed double confluent Heun equation, nondestructive singular point, Frobenius norm, third Painlevé transcendent, transport equation, isomonodromicity
Funding agency
This work was supported by ongoing institutional funding. No additional grants to carry out or direct this particular research were obtained.
Citation:
S. I. Tertichniy, “On the Monodromy-Preserving Deformation of a Double Confluent Heun Equation”, Topology, Geometry, Combinatorics, and Mathematical Physics, Collected papers. Dedicated to Victor Matveevich Buchstaber on the occasion of his 80th birthday, Trudy Mat. Inst. Steklova, 326, Steklov Math. Inst., Moscow, 2024, 330–367; Proc. Steklov Inst. Math., 326 (2024), 303–338