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arXiv · 1105.3888

On restricted Analytic Gradients on Analytic Isolated Surface Singularities

Vincent Grandjean·Fernando Sanz
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Abstract

Let (X,O) be a real analytic isolated surface singularity at the origin o of a real analytic manifold M equipped with a real analytic metric g. Given a real analytic function f:(M,O) --> (R,0) singular at O, we prove that the gradient trajectories for the metric g|(X,O) of the restriction f|X escaping from or ending up at the origin O do not oscillate. Such a trajectory is thus a sub-pfaffian set. Moreover, in each connected component of X\O where the restricted gradient does not vanish, there is always a trajectory accumulating at O and admitting a formal asymptotic expansion at O

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Vincent Grandjean, Fernando Sanz. 2011-05-19. On restricted Analytic Gradients on Analytic Isolated Surface Singularities. https://doi.org/10.1016/j.jde.2013.05.020

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