Abstract
We discuss the relationship between the frequency and the growth of H-harmonic functions on the Heisenberg group. Precisely, we prove that an H-harmonic function must be a polynomial if its frequency is globally bounded. Moreover, we show that a class of H-harmonic functions are homogeneous polynomials provided that the frequency of such a function is equal to some constant.
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Liu, H., Tian, L. & Yang, X. The growth of H-harmonic functions on the Heisenberg group. Sci. China Math. 57, 795–806 (2014). https://doi.org/10.1007/s11425-013-4638-5
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DOI: https://doi.org/10.1007/s11425-013-4638-5