Discussion Overview
The discussion centers on the search for perturbation theory formulas for energies and states up to fourth order, specifically in the context of quantum mechanics. Participants explore resources and methods for obtaining these formulas without deriving them from first principles.
Discussion Character
- Exploratory, Technical explanation, Homework-related
Main Points Raised
- One participant requests sources for perturbation theory formulas up to fourth order, noting the limitations of existing resources like Wikipedia.
- Another participant suggests Niholas Wheeler's "Higher-Order Spectral Perturbation" as a potential resource for fourth and fifth order, specifically mentioning its focus on non-degenerate perturbation theory.
- A third participant expresses gratitude for the suggestion and confirms their work is within the non-degenerate case.
- One participant shares their personal approach of using a variational matrix to implicitly include higher order terms, suggesting it may be as efficient as calculating the fourth order terms directly.
Areas of Agreement / Disagreement
Participants generally agree on the need for resources related to fourth order perturbation theory, but there are differing approaches to handling higher order terms, with no consensus on the best method.
Contextual Notes
Limitations include the focus on non-degenerate perturbation theory and the potential absence of comprehensive resources for higher order states.