English

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

Classical Analysis and ODEs 2023-07-25 v2 Number Theory

Abstract

We prove sharp decoupling inequalities for all degenerate surfaces of codimension two in R5\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.

Keywords

Cite

@article{arxiv.1912.03995,
  title  = {Decoupling for two quadratic forms in three variables: a complete characterization},
  author = {Shaoming Guo and Changkeun Oh and Joris Roos and Po-Lam Yung and Pavel Zorin-Kranich},
  journal= {arXiv preprint arXiv:1912.03995},
  year   = {2023}
}

Comments

v2: 19 pages, small corrections following referee report

R2 v1 2026-06-23T12:39:54.336Z