English

On resolution to Wu's Conjecture

Complex Variables 2009-09-03 v1

Abstract

In this series of studies on Cauchy's function f(z)f(z) (z=x+iyz=x+iy) and its integral J[f(z)](2πi)1Cf(t)dt/(tz)J[f(z)]\equiv (2\pi i)^{-1}\oint_C f(t)dt/(t-z) taken along a Jordan contour CC, the aim is to investigate their comprehensive properties over the entire zz-plane consisted of the simply-connected closed domain D+{\cal D}^+ bounded by CC and the open domain D{\cal D}^- outside CC. This article attempts to solve an inverse problem that Cauchy function f(z)f(z), regular in D+{\cal D^+} and on CC, has a singularity distribution in D{\cal D}^- which can be determined in analytical form in terms of the values f(t)f(t) numerically prescribed on CC, which is Wu's conjecture[1]. It is resolved here for f(z)f(z) having (i) a single, (ii) double, or (iii) multiple singularities of the types (I) ΣjNMj(zjz)kj\Sigma_j^N M_j(z_j-z)^{k_j}, (II) Mlog(z2z)M_\ell\log(z_2-z), by having their power series expanded in zz and matched on a unit circle (t=eiθ,πθ<π(t=e^{i\theta}, -\pi\leq\theta<\pi for contour CC) with the numerically prescribed Fourier series f(z)=Σ0cneinθf(z)=\Sigma_0^\infty c_ne^{in\theta} for solution. The mathematical methods used include (a) complex algebra for cases (i)-(ii), (b) for case (iii) a general asymptotic method developed here for resolution to the Conjecture by induction, and (c) the generalized Hilbert transforms to expound essential singularities. This Conjecture has an advanced version for f(z)f(z) to be given only one of its two conjugate functions on CC to suffice, and another for the complement function F(z)F(z) defined as being regular in domain D{\cal D}^- and having singularities in D+{\cal D^+}. These new methods are applicable to all relevant problems in mathematics, engineering and mathematical physics requiring breakthrough by having the exterior singularities resolved.

Keywords

Cite

@article{arxiv.0909.0298,
  title  = {On resolution to Wu's Conjecture},
  author = {Theodore Yaotsu Wu},
  journal= {arXiv preprint arXiv:0909.0298},
  year   = {2009}
}

Comments

15 pages, 1 figure

R2 v1 2026-06-21T13:41:24.847Z