Meshfree Variational Physics Informed Neural Networks (MF-VPINN): an adaptive training strategy

In this paper we introduce a Meshfree Variational Physics Informed Neural Network. It is a Variational Physics Informed Neural Network that does not require the generation of a triangulation of the entire domain and that can be trained with an adaptive set of test functions. In order to generate the test space we exploit an a posteriori error indicator and add test functions only where the error is higher. Four training strategies are proposed and compared. Numerical results show that the accuracy is higher than the one of a Variational Physics Informed Neural Network trained with the same number of test functions but defined on a quasi-uniform mesh.