81XX 


Quantum theory 

81Qxx 

General mathematical topics and methods in quantum theory 


81Q05 
Closed and approximate solutions to the SchrÃ¶dinger, Dirac, KleinGordon and other quantummechanical equations 


81Q10 
Selfadjoint operator theory in quantum theory, including spectral analysis 


81Q15 
Perturbation theories for operators and differential equations 


81Q20 
Semiclassical techniques including WKB and Maslov methods 


81Q30 
Feynman integrals and graphs; applications of algebraic topology and algebraic geometry [See also 14D05, 32S40] 


81Q40 
BetheSalpeter and other integral equations 


81Q50 
Quantum chaos [See also 37Dxx] 


81Q60 
Supersymmetric quantum mechanics 


81Q70 
Differentialgeometric methods, including holonomy, Berry and Hannay phases, etc. 


81Q99 
None of the above, but in this section 