---
abstract: 'We derive explicit semiclassical quantisation conditions for the Dirac and Pauli equations.  We show that the spin degree of freedom yields a contribution which is of the same order of magnitude as the Maslov correction in Einstein-Brillouin-Keller quantisation.  In order to obtain this result a generalisation of the notion of integrability for a certain skew product flow of classical translational dynamics and classical spin precession has to be derived.  Among the examples discussed is the relativistic Kepler problem with Thomas precession, whose treatment sheds some light on the amazing success of Sommerfeld’s theory of fine structure \[Ann.  Phys. ( Leipzig) [**51**]{} (1916) 1–91\].' 
bibliography:
- 'literatur.bib'
---

December 2002\

[ **Semiclassical quantisation rules for the Dirac and Pauli equations**]{}\

[^1]

Acknowledgement {#acknowledgement .unnumbered}
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I would like to thank Jens Bolte for helpful discussions.  This work was supported by the Deutsche Forschungsgemeinschaft under contract no.  Ste 241/10-2. 

[^1]: present address, email: [stefan.keppeler@matfys.lth.se]{}
