Lack of Gevrey solvability for a model operator

Enrico Bernardi

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arXiv · 2605.27054

Lack of Gevrey solvability for a model operator

Enrico Bernardi

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Abstract

We prove that the Cauchy problem for the model hyperbolic operator in $ \R^{4} $ \[ Q=-D_t^2+2xD_tD_y+D_x^2+x^3D_y^2+D_z^2+z^2D_y^2 \] is not locally solvable at the origin, in the Gevrey $s$ class if $s>6$.

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Enrico Bernardi. 2026-05-26. Lack of Gevrey solvability for a model operator. https://arxiv.org/abs/2605.27054

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