# Category:Perturbation theory

Physics portal |

Here is a list of articles in the Perturbation theory category of the Physics portal. This category deals with topics in perturbation theory and variational principles, which commonly occur in the theory of differential equations, with problems in quantum mechanics forming an important subset thereof.

## Pages in category "Perturbation theory"

The following 22 pages are in this category, out of 22 total.

- Perturbation theory
*(physics)* - Perturbation theory (quantum mechanics)
*(physics)*

### E

- Eigenvalue perturbation
*(computing)*

### F

- Fermi's golden rule
*(physics)*

### I

- Intruder state
*(chemistry)*

### L

- Laplace's method
*(computing)*

### M

- Matrix element
*(physics)* - Method of steepest descent
*(computing)* - Multiple-scale analysis
*(computing)*

### N

- Non-perturbative
*(computing)*

### O

- Order of approximation
*(computing)*

### P

- Perturbation problem beyond all orders
*(computing)* - Poincaré–Lindstedt method
*(computing)*

### R

- Ritz method
*(computing)*

### S

- Saddlepoint approximation method
*(computing)* - Schwinger's quantum action principle
*(physics)* - Sequence transformation
*(computing)* - Series acceleration
*(computing)* - Singular perturbation
*(computing)* - Stationary phase approximation
*(computing)*

### T

- Tikhonov's theorem (dynamical systems)
*(computing)*

### V

- Variational perturbation theory
*(computing)*