English

On implicitly oscillatory quadrilinear integrals

Classical Analysis and ODEs 2022-04-11 v1

Abstract

For quadrilinear functionals Bj=14(fjφj)\int_B \prod_{j=1}^4 (f_j\circ\varphi_j), where BR2B\subset{\mathbb R}^2 is a ball, φj:BR1\varphi_j:B\to{\mathbb R}^1 are real analytic submersions, and fjL(R1)f_j\in L^\infty({\mathbb R}^1) are bounded and measurable, we seek a majorization of the integral by a product of negative order Sobolev norms of the factors fjf_j. An obvious necessary condition is that any smooth solution of j(gjφj)0\sum_j (g_j\circ\varphi_j)\equiv 0, in any connected open set, must be constant. Assuming this condition and certain auxiliary hypotheses, we establish an upper bound of the desired type. The proof relies in part on a three term sublevel set inequality established in a companion paper.

Keywords

Cite

@article{arxiv.2204.03780,
  title  = {On implicitly oscillatory quadrilinear integrals},
  author = {Michael Christ},
  journal= {arXiv preprint arXiv:2204.03780},
  year   = {2022}
}
R2 v1 2026-06-24T10:41:53.619Z