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arXiv · 2604.27717

Inscriptions of Isosceles Trapezoids in Jordan Curves

Abstract

We construct a Lagrangian Floer homology whose chain complex is generically generated by the inscriptions of isosceles trapezoids in a smooth Jordan curve. This is an extension of Greene and Lobb's Jordan Floer homology (arXiv:2404.05179), which we also call Jordan Floer homology. Its non-triviality re-establishes that every smooth Jordan curve inscribes every isosceles trapezoid. By consideration of the spectral invariants associated with the real filtration known as the action filtration, we establish new cases of non-smooth Jordan curves which admit inscriptions of isosceles trapezoids.

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Adam Barber. 2026-04-30. Inscriptions of Isosceles Trapezoids in Jordan Curves. https://arxiv.org/abs/2604.27717

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