Abstract
The theta map sends code polynomials into the ring of Siegel modular forms of even weights. Explicit description of the image is known for $g\leq 3$ and the surjectivity of the theta map follows. Instead it is known that this map is not surjective for $g\geq 5$. In this paper we discuss the possibility of an embedding between the associated projective varieties. We prove that this is not possible for $g\geq 4$ and consequently we get the non surjectivity of the graded rings for the remaining case $g=4$.
Citation
Manabu Oura. Riccardo Salvati Manni. "On the image of code polynomials under theta map." J. Math. Kyoto Univ. 48 (4) 895 - 906, 2008. https://doi.org/10.1215/kjm/1250271322
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