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arXiv · 2209.14762

Long-time asymptotic estimate and a related inverse source problem for time-fractional wave equations

Xinchi Huang·Yikan Liu
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Abstract

Lying between traditional parabolic and hyperbolic equations, time-fractional wave equations of order $\alpha\in(1,2)$ in time inherit both decaying and oscillating properties. In this article, we establish a long-time asymptotic estimate for homogeneous time-fractional wave equations, which readily implies the strict positivity/negativity of the solution for $t\gg1$ under some sign conditions on initial values. As a direct application, we prove the uniqueness for a related inverse source problem on determining the temporal component.

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Xinchi Huang, Yikan Liu. 2022-09-29. Long-time asymptotic estimate and a related inverse source problem for time-fractional wave equations. https://doi.org/10.1007/978-981-99-2408-0_11

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