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arXiv · 2511.21442

The Self-Projecting Grassmannian

Alheydis Geiger·Francesca Zaffalon
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Abstract

We introduce the self-projecting Grassmannian, an irreducible subvariety of the Grassmannian parametrizing linear subspaces that satisfy a generalized self-duality condition. We study its relation to classical moduli spaces, such as the moduli spaces of pointed curves of genus $g$, as well as to other natural subvarieties of the Grassmannian. We further translate the self-projectivity condition in the combinatorial language of matroids, introducing self-projecting matroids, and we computationally investigate their realization spaces inside the self-projecting Grassmannian.

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Alheydis Geiger, Francesca Zaffalon. 2025-11-26. The Self-Projecting Grassmannian. https://arxiv.org/abs/2511.21442

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