Physic-Informed Neural Networks (PINN) are neural networks (NNs) that encode model equations, like Partial Differential Equations (PDE), as a component of the neural network itself. PINNs are nowadays used to solve PDEs, fractional equations, and integral-differential equations. This novel methodology has arisen as a multi-task learning framework in which a NN must fit observed data while reducing a PDE residual. This article provides a comprehensive review of the literature on PINNs: while the primary goal of the study was to characterize these networks and their related advantages and disadvantages, the review also attempts to incorporate publications on a larger variety of issues, including physics-constrained neural networks (PCNN), where the initial or boundary conditions are directly embedded in the NN structure rather than in the loss functions. The study indicates that most research has focused on customizing the PINN through different activation functions, gradient optimization techniques, neural network structures, and loss function structures. Despite the wide range of applications for which PINNs have been used, by demonstrating their ability to be more feasible in some contexts than classical numerical techniques like Finite Element Method (FEM), advancements are still possible, most notably theoretical issues that remain unresolved.

文章综述了物理学启发的神经网络（PINN）的文献，并介绍了其特点和优缺点。此外，研究还包括了使用PINN以及它的许多其他变体解决PDE、分数方程、积分微分方程和随机PDE的广泛应用领域，以及它们的定制化方法，如不同的激活函数、梯度优化技术、神经网络结构和损失函数结构。虽然该方法被证明在某些情况下比有限元方法更可行，但它仍面临理论问题尚未解决。

通过物理知识指导的神经网络科学机器学习：现状和未来展望