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arXiv · 1609.06481

Newforms of half-integral weight: the minus space counterpart

Ehud Moshe Baruch·Soma Purkait
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Abstract

We define a subspace of the space of holomorphic modular forms of weight $k+1/2$ and level $4M$ where $M$ is odd and square-free. We show that this subspace is isomorphic under the Shimura-Niwa correspondence to the space of newforms of weight $2k$ and level $2M$ and that this is a Hecke isomorphism. The space we define is a proper subspace of the orthogonal complement of the Kohnen plus space if the Kohnen plus space is nonzero.

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Ehud Moshe Baruch, Soma Purkait. 2016-09-21. Newforms of half-integral weight: the minus space counterpart. https://doi.org/10.4153/s0008414x19000233

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