We consider the hypergeometric equation (1 − t)∂t∂t∂g + x3g = 0, whose unique analytic solution φ1(t; x) = 1 + O(t) near t = 0 for t = 1 becomes a generating function for multiple zeta values φ1(1; x) = f3(x) = 1 − ζ(3)x3 + ζ(3, 3)x6 − …. We apply the so-called WKB method to study solutions of the hypergeometric equation for large x and we calculate corresponding Stokes matrices. We prove that the function f3(x) near x = ∞ is also expressed via WKB type functions which subject to some Stokes phenomenon. This implies that f3(x) satisfies a sixth order linear differential equation with irregular singularity at infinity.
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The deformation |$\left\lbrace \mathbb {T}_{\kappa }\right\rbrace _{0\le \kappa \le 1}$| can be given explicitly as follows: 0 ⩽ α, β ⩽ 2π. Here the modulus A(α) is a smooth function such that: A(α) = |Pσ| in δ–neighborhood of |$\alpha _{\sigma }=\arg P_{\sigma },$| A(α) = 1 outside 2δ–neighborhood of the critical set {ασ} and A(α) varies between 1 and |Pσ|; in the same way, the modulus B(β) is defined. It is easy that Pκ(α), Q κ(α, β) = [B2/A]κ/2ei(β − α/2) and Rκ(α, β) = [B2A]−κ/2e−i(β + α/2) avoid the singular value t−1/3, provided the constant δ is sufficiently small.
\begin{equation*}P_{\kappa }(\alpha )=A(\alpha )^{\kappa }e^{i\alpha },\text{ }S_{\kappa }(\beta )=B(\beta )^{\kappa }e^{i\beta },\end{equation*}
© 2012 American Institute of Physics.
2012
American Institute of Physics
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