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arXiv · hep-th/9806100

Masslessness in $n$-dimensions

Eugenios Angelopoulos·Mourad Laoues
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Abstract

We determine the representations of the ``conformal'' group ${\bar{SO}}_0(2, n)$, the restriction of which on the ``Poincaré'' subgroup ${\bar{SO}}_0(1, n-1).T_n$ are unitary irreducible. We study their restrictions to the ``De Sitter'' subgroups ${\bar{SO}}_0(1, n)$ and ${\bar{SO}}_0(2, n-1)$ (they remain irreducible or decompose into a sum of two) and the contraction of the latter to ``Poincaré''. Then we discuss the notion of masslessness in $n$ dimensions and compare the situation for general $n$ with the well-known case of 4-dimensional space-time, showing the specificity of the latter.

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Eugenios Angelopoulos, Mourad Laoues. 1998-06-12. Masslessness in $n$-dimensions. https://doi.org/10.1142/s0129055x98000082

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