# Fermat's Variational Principle for Anisotropic Inhomogeneous Media

@article{erven2002FermatsVP,
title={Fermat's Variational Principle for Anisotropic Inhomogeneous Media},
author={Vlastislav {\vC}erven{\'y}},
journal={Studia Geophysica et Geodaetica},
year={2002},
volume={46},
pages={567-588}
}
• V. Červený
• Published 1 July 2002
• Mathematics
• Studia Geophysica et Geodaetica
AbstractFermat's variational principle states that the signal propagates from point S to R along a curve which renders Fermat's functional $$\mathcal{I}$$ (l) stationary. Fermat's functional $$\mathcal{I}$$ (l) depends on curves l which connect points S and R, and represents the travel times from S to R along l. In seismology, it is mostly expressed by the integral $$\mathcal{I}$$ (l) = $$\smallint _S^R \mathcal{L}$$ (xk,xk')du, taken along curve l, where ℒ(xk,xk') is the relevant…
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