Poster
in
Workshop: Machine Learning and the Physical Sciences
Neural Symplectic Integrator with Hamiltonian Inductive Bias for the Gravitational N-body Problem
Maxwell Xu Cai · Simon Portegies Zwart · Damian Podareanu
Abstract:
The gravitational NN-body problem, which is fundamentally important in astrophysics to predict the motion of NN celestial bodies under the mutual gravity of each other, is usually solved numerically because there is no known general analytical solution for N>2N>2. Can an NN-body problem be solved accurately by a neural network (NN)? Can a NN observe long-term conservation of energy and orbital angular momentum? Inspired by Wistom \& Holman (1991) symplectic map, we present a neural NN-body integrator for splitting the Hamiltonian into a two-body part, solvable analytically, and an interaction part that we approximate with a NN. Our neural symplectic NN-body code integrates a general three-body system at O(N)O(N) complexity for 105105 steps without diverting from the ground truth dynamics obtained from a traditional NN-body integrator. Moreover, it exhibits good inductive bias by successfully predicting the dynamical evolution of NN-body systems that are no part of the training set.
Chat is not available.