Spherical transverse M5-branes in matrix theory

How the transverse M5-branes are described in the matrix-model formulations of M-theory has been a long-standing problem. We consider this problem for M-theory on the maximally supersymmetric pp-wave geometry, which admits transverse spherical M5-branes with zero light-cone energy. By using the localization, we directly analyze the strong coupling region of the corresponding matrix theory called the plane wave matrix model (PWMM). Under the assumption that the low-energy modes of the scalar fields in PWMM become mutually commuting in the strong coupling region, we show that the eigenvalue density of the $SO(6)$ scalars in the low-energy region exactly agrees with the shape of the spherical M5-branes in the decoupling limit. This result gives strong evidence that the transverse M5-branes are indeed contained in the matrix theory and the theory realizes a second quantization of the M-theory.