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arXiv · 1912.03995

Decoupling for two quadratic forms in three variables: a complete characterization

Shaoming Guo·Changkeun Oh·Joris Roos·Po-Lam Yung·Pavel Zorin-Kranich
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Abstract

We prove sharp decoupling inequalities for all degenerate surfaces of codimension two in $\mathbb{R}^5$ given by two quadratic forms in three variables. Together with previous work by Demeter, Guo, and Shi in the non-degenerate case (arXiv:1609.04107), this provides a classification of decoupling inequalities for pairs of quadratic forms in three variables.

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Shaoming Guo, Changkeun Oh, Joris Roos, Po-Lam Yung, Pavel Zorin-Kranich. 2019-12-09. Decoupling for two quadratic forms in three variables: a complete characterization. https://doi.org/10.4171/rmi%2F1332

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