Uniqueness for the inverse Schrödinger problem in the plane with $L^p$ potentials, $p>1$

Cătălin I. Cârstea; Jenn-Nan Wang

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arXiv · 2609.28046

Uniqueness for the inverse Schrödinger problem in the plane with $L^p$ potentials, $p>1$

Cătălin I. Cârstea·Jenn-Nan Wang

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Abstract

Let $Ω\subset\mathbb R^2$ be a bounded smooth domain. We prove that the weak Dirichlet-to-Neumann map for $-Δ+V$ uniquely determines every complex-valued potential $V\in L^p(Ω)$, $p>1$, provided that zero is not a Dirichlet eigenvalue. This extends the previously known range $p>4/3$ to all $p>1$. The proof uses Bukhgeim's quadratic-phase solutions and an average of Alessandrini's identity over the phase center. After separating the Neumann-series tails, we show that each remaining Born term tends to zero. The fixed-order estimates combine bounds for the absolute kernels with oscillatory cancellation and a duality argument for the product of the two Cauchy transforms.

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Cătălin I. Cârstea, Jenn-Nan Wang. 2026-09-23. Uniqueness for the inverse Schrödinger problem in the plane with $L^p$ potentials, $p>1$. https://arxiv.org/abs/2609.28046

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