Measure Estimates of Nodal Sets of Polyharmonic Functions

Abstract

This paper deals with the function u which satisfies △ ^k u = 0, where k ≥ 2 is an integer. Such a function u is called a polyharmonic function. The author gives an upper bound of the measure of the nodal set of u, and shows some growth property of u.

Keywords

Polyharmonic function / Nodal set / Frequency / Measure estimate / Growth property

References

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