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arXiv · 0802.0409

Generalised energy conservation law for the wave equations with variable propagation speed

Fumihiko Hirosawa·Jens Wirth
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Abstract

We investigate the long time behaviour of the $L^2$-energy of solutions to wave equations with variable speed. The novelty of the approach is the combination of estimates for higher order derivatives of the coefficient with a stabilisation property.

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Fumihiko Hirosawa, Jens Wirth. 2008-05-29. Generalised energy conservation law for the wave equations with variable propagation speed. https://doi.org/10.1016/j.jmaa.2009.04.048

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