Multiplicity of normalized solutions to a class of nonlinear fractional Schrödinger-Poisson systems with Hardy potential

In this paper, we study the multiplicity of normalized solutions to a class of nonlinear fractional Schr & ouml;dinger-Poisson systems with Hardy potential. First, by using some ideas of the fountain theorem, we define a sequence of minimax values, and then we prove that these minimax values are critical values of the energy function restricted to a constraint set, which leads to the multiplicity of normalized solutions and extends some related results.