Logarithmic Branch Point
A branch point whose neighborhood of values wrap around an infinite number of times as their complex arguments are varied. The point z=0 under the function lnz is therefore a logarithmic branch point. Logarithmic branch points are equivalent to logarithmic singularities.
See also
Algebraic Branch Point, Branch Point, Logarithmic SingularityExplore with Wolfram|Alpha
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Cite this as:
Weisstein, Eric W. "Logarithmic Branch Point." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/LogarithmicBranchPoint.html