GAPLSSNESS. “This excitation lowers the energy thresholds of the higher angular momentum modes, so that the theory delivers a set of the gapless modes with their number scaling as the area of a ‐dimensional sphere.”
https://onlinelibrary.wiley.com/doi/full/10.1002/prop.201800007?casa_token=GdPRXs_tGLEAAAAA%3Ag-pxPMtkcleTYDUNK3mYGfpEzKRyc2LqQknTgFFB7dkYFDL8rDe2s0f4_0Q0oKjXD4_AEgFPGWolVTQ