article published yes Terence Tao author Monica Visan author 056daca0-b8d1-11f0-964f-f91054abf8ca Xiaoyi Zhang author We undertake a comprehensive study of the nonlinear Schrödinger equation (mathematical formular) where u(t, x) is a complex-valued function in spacetime R, xRn/x, λ1 and λ2 are nonzero real constants, and (mathematical formular). We address questions related to local and global well-posedness, finite time blowup, and asymptotic behaviour. Scattering is considered both in the energy space H^1(ℝ n ) and in the pseudoconformal space Σ := {f ∈ H^1(ℝ^n); xf ∈ L^2(ℝ^n)}. Of particular interest is the case when both nonlinearities are defocusing and correspond to the L2/x-critical, respectively H1/x-critical NLS, that is, λ1, λ2 > 0 and (mathematical formular) . The results at the endpoint p1= 4/n are conditional on a conjectured global existence and spacetime estimate for the L2/x-critical nonlinear Schrödinger equation, which has been verified in dimensions n ≥ 2 for radial data in Tao et al. (Tao et al. to appear a,b) and Killip et al. (preprint). As an off-shoot of our analysis, we also obtain a new, simpler proof of scattering in H1/x for solutions to the nonlinear Schrödinger equation (mathematical formular) with 4/n < p < 4/n-2, which was first obtained by Ginibre and Velo (Citation1985). Informa UK Limited2007 eng Energy-criticalMass-criticalNonlinear Schrödinger equationWellposedness 0360-5302 1532-4133 math/051107010.1080/03605300701588805 3281281-1343 yes Tao, T., Vişan, M., &#38; Zhang, X. (2007). The nonlinear Schrödinger equation with combined power-type nonlinearities. <i>Communications in Partial Differential Equations</i>. Informa UK Limited. <a href="https://doi.org/10.1080/03605300701588805">https://doi.org/10.1080/03605300701588805</a> Tao T, Vişan M, Zhang X. 2007. The nonlinear Schrödinger equation with combined power-type nonlinearities. Communications in Partial Differential Equations. 32(8), 1281–1343. Tao, Terence, Monica Vişan, and Xiaoyi Zhang. “The Nonlinear Schrödinger Equation with Combined Power-Type Nonlinearities.” <i>Communications in Partial Differential Equations</i>. Informa UK Limited, 2007. <a href="https://doi.org/10.1080/03605300701588805">https://doi.org/10.1080/03605300701588805</a>. Tao T, Vişan M, Zhang X. The nonlinear Schrödinger equation with combined power-type nonlinearities. <i>Communications in Partial Differential Equations</i>. 2007;32(8):1281-1343. doi:<a href="https://doi.org/10.1080/03605300701588805">10.1080/03605300701588805</a> T. Tao, M. Vişan, and X. Zhang, “The nonlinear Schrödinger equation with combined power-type nonlinearities,” <i>Communications in Partial Differential Equations</i>, vol. 32, no. 8. Informa UK Limited, pp. 1281–1343, 2007. Tao, Terence, et al. “The Nonlinear Schrödinger Equation with Combined Power-Type Nonlinearities.” <i>Communications in Partial Differential Equations</i>, vol. 32, no. 8, Informa UK Limited, 2007, pp. 1281–343, doi:<a href="https://doi.org/10.1080/03605300701588805">10.1080/03605300701588805</a>. T. Tao, M. Vişan, X. Zhang, Communications in Partial Differential Equations 32 (2007) 1281–1343. 220472026-06-19T07:49:46Z2026-06-25T08:04:20Z