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arXiv · 2203.10355

Natural annihilators and operators of constant rank over $\mathbb{C}$

Franz Gmeineder·Stefan Schiffer
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Abstract

Even if the Fourier symbols of two constant rank differential operators have the same nullspace for each non-trivial phase space variable, the nullspaces of those differential operators might differ by an infinite dimensional space. Under the natural condition of constant rank over $\mathbb{C}$, we establish that the equality of nullspaces on the Fourier symbol level already implies the equality of the nullspaces of the differential operators in $\mathscr{D}'$ modulo polynomials of a fixed degree. In particular, this condition allows to speak of natural annihilators within the framework of complexes of differential operators. As an application, we establish a Poincar\'{e}-type lemma for differential operators of constant complex rank in two dimensions.

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Franz Gmeineder, Stefan Schiffer. 2022-03-19. Natural annihilators and operators of constant rank over $\mathbb{C}$. https://arxiv.org/abs/2203.10355

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