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On Hessian Limit Directions along Gradient Trajectories

Published online by Cambridge University Press:  20 November 2018

Vincent Grandjean*
Affiliation:
Departamento de Matemática, UFC, Av. Humberto Monte s/n, Campus do Pici Bloco 914, CEP 60.455-760, Fortaleza-CE, Brasil, e-mail: [email protected]
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Abstract

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Given a non-oscillating gradient trajectory $\left| \text{ }\!\!\gamma\!\!\text{ } \right|$ of a real analytic function $f$, we show that the limit $v$ of the secants at the limit point $0$ of $\left| \text{ }\!\!\gamma\!\!\text{ } \right|$ along the trajectory $\left| \text{ }\!\!\gamma\!\!\text{ } \right|$ is an eigenvector of the limit of the direction of the Hessian matrix Hess$\left( f \right)$ at $0$ along $\left| \text{ }\!\!\gamma\!\!\text{ } \right|$. The same holds true at infinity if the function is globally sub-analytic. We also deduce some interesting estimates along the trajectory. Away from the ends of the ambient space, this property is of metric nature and still holds in a general Riemannian analytic setting.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 2013

References

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