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arXiv · hep-th/9408145

The exponential map for the unitary group SU(2,2)

A. O. Barut·J. R. Zeni·A. J. Laufer
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Abstract

In this article we extend our previous results for the orthogonal group, $SO(2,4)$, to its homomorphic group $SU(2,2)$. Here we present a closed, finite formula for the exponential of a $4\times 4$ traceless matrix, which can be viewed as the generator (Lie algebra elements) of the $SL(4,C)$ group. We apply this result to the $SU(2,2)$ group, which Lie algebra can be represented by the Dirac matrices, and discuss how the exponential map for $SU(2,2)$ can be written by means of the Dirac matrices.

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A. O. Barut, J. R. Zeni, A. J. Laufer. 1994-08-30. The exponential map for the unitary group SU(2,2). https://doi.org/10.1088/0305-4470%2F27%2F20%2F017

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