2020/12/11 by Chen, Xianghong, Duong, Xuan Thinh, Lee, Sanghyuk +1 · 1 citation
#35B45 #35J0 #42B37 #Analysis of PDEs (math.AP) #Classical Analysis and ODEs (math.CA) #FOS: Mathematics
paper · doi:10.48550/arxiv.2012.06313
Let Δ\mathbb Sn denote the Laplace-Beltrami operator on the n-dimensional unit sphere \mathbb Sn. In this paper we show that ‖ e^it Δ\mathbb Snf ‖L4([0, 2π) × \mathbb Sn) ≤ C ‖ f‖Wα, 4 (\mathbb Sn) holds provided that n≥ 2, α> (n-2)/4. The range of α is sharp up to the endpoint. As a consequence, we obtain space-time estimates for the Schrödinger propagator e^it Δ\mathbb Sn on the Lp spaces for 2≤ p≤ ∞. We also prove that for zonal functions on \mathbb Sn, the Schrödinger maximal operator sup0≤ t<2π |e^itΔ\mathbb Sn f| is bounded from Wα, 2(\mathbb Sn) to L(6n)/(3n-2)(\mathbb Sn) whenever α>1/3.