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From Poincare to affine invariance: How does the Dirac equation generalize?

Ingo Kirsch·Djordje Sijacki
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Abstract

A generalization of the Dirac equation to the case of affine symmetry, with SL(4,R) replacing SO(1,3), is considered. A detailed analysis of a Dirac-type Poincare-covariant equation for any spin j is carried out, and the related general interlocking scheme fulfilling all physical requirements is established. Embedding of the corresponding Lorentz fields into infinite-component SL(4,R) fermionic fields, the constraints on the SL(4,R) vector-operator generalizing Dirac's gamma matrices, as well as the minimal coupling to (Metric-)Affine gravity are studied. Finally, a symmetry breaking scenario for SA(4,R) is presented which preserves the Poincare symmetry.

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Ingo Kirsch, Djordje Sijacki. 2002-05-30. From Poincare to affine invariance: How does the Dirac equation generalize?. https://doi.org/10.1088/0264-9381%2F19%2F12%2F305

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