English

$L^p$-boundedness of wave operators for fourth order Schr\"odinger operators with zero resonances on $\mathbb{R}^3$

Analysis of PDEs 2025-05-12 v4 Mathematical Physics Classical Analysis and ODEs math.MP

Abstract

Let H=Δ2+VH = \Delta^2 + V be the fourth-order Schr\"odinger operator on R3\mathbb{R}^3 with a real-valued fast-decaying potential VV. If zero is neither a resonance nor an eigenvalue of HH, then it was recently shown that the wave operators W±(H,Δ2)W_\pm(H, \Delta^2) are bounded on Lp(R3)L^p(\mathbb{R}^3) for all 1<p<1 < p < \infty and unbounded at the endpoints p=1p=1 and p=p=\infty. This paper is to further establish the LpL^p-boundedness of W±(H,Δ2)W_\pm(H, \Delta^2) that exhibit all types of singularities at the zero energy threshold. We first prove that W±(H,Δ2)W_\pm(H, \Delta^2) are bounded on Lp(R3)L^p(\mathbb{R}^3) for all 1<p<1 < p < \infty in the first kind resonance case, and then proceed to establish for the second kind resonance case that they are bounded on Lp(R3)L^p(\mathbb{R}^3) for all 1<p<31 < p < 3, but not if 3p3 \le p \le \infty. In the third kind resonance case, we also show that W±(H,Δ2)W_\pm(H, \Delta^2) are bounded on Lp(R3)L^p(\mathbb{R}^3) for all 1<p<31<p<3 and generically unbounded on Lp(R3)L^p(\R^3) for any 3p3\le p\le\infty. Moreover, it is also shown that W±(H,Δ2)W_\pm(H, \Delta^2) are bounded on Lp(R3)L^p(\R^3) for all 3p<3\le p<\infty if in addition HH has the zero eigenvalue, but no pp-wave zero resonances and all zero eigenfunctions are orthogonal to xixjxkVx_ix_jx_kV in L2(R3)L^2(\R^3) for all i,j,k=1,2,3i,j,k=1,2,3 with x=(x1,x2,x3)R3x=(x_1,x_2,x_3)\in \R^3. These results describe precisely the validity of the LpL^p-boundedness of W±(H,Δ2)W_\pm(H, \Delta^2) in R3\mathbb{R}^3 for all types of singularities at the zero energy threshold with some exceptions for the endpoint cases p=1,p=1,\infty. As an application, LpL^p-LqL^q decay estimates are also derived for the fourth-order Schr\"odinger equations and Beam equations with zero resonance singularities.

Keywords

Cite

@article{arxiv.2311.06763,
  title  = {$L^p$-boundedness of wave operators for fourth order Schr\"odinger operators with zero resonances on $\mathbb{R}^3$},
  author = {Haruya Mizutani and Zijun Wan and Xiaohua Yao},
  journal= {arXiv preprint arXiv:2311.06763},
  year   = {2025}
}

Comments

50 pages, it is the final version published in JFA 2025