Kavli Affiliate: Nickolay Gnedin | First 5 Authors: Nickolay Y. Gnedin, , , , | Summary: I describe a modification to the original Fast Multipole Method (FMM) of Greengard & Rokhlin that approximates the gravitation field of an FMM cell as a small uniform grid (a "gridlet") of effective masses. The effective masses on a […]