What does Variational Perturbation Theory allow us to do?

Approximate behavior of complex quantum systems: Variational Perturbation Theory allows us to approximate the behavior of complex quantum systems, making it a valuable tool in theoretical physics and quantum mechanics. By introducing small perturbations to a known system and studying its response, this theory provides a systematic framework for understanding the behavior of quantum systems under external influences or interactions. It allows us to make predictions about the properties and behavior of atoms, molecules, and other quantum systems, helping us gain insights into the fundamental principles of quantum mechanics and their applications in various fields of science and technology.