Generating Lie and gauge free differential (super)algebras by expanding Maurer-Cartan forms and Chern-Simons supergravity
Jose A. de Azcarraga, Jose M. Izquierdo, Moises Picon, Oscar Varela
TL;DR
The paper introduces the expansion method, a procedure to generate new (super)algebras $\mathcal{G}(N_0,\ldots,N_n)$ from a given algebra $\mathcal{G}$ by rescaling group parameters and expanding Maurer–Cartan forms in powers of $\lambda$. This approach extends contractions and deformations, and, under Weimar–Woods conditions, recovers generalized Inönü–Wigner contractions while also producing higher-dimensional algebras. It is applied to derive the M-theory superalgebra from $\mathrm{osp}(1|32)$ (with Lorentz part included) as $\mathrm{osp}(1|32)(2,1,2)$, and is extended to gauge free differential algebras and Chern–Simons theories, with explicit CS constructions in $D=3$ illustrating the link to CS supergravity. The overall framework provides a versatile tool to relate and build extended symmetry structures in supergravity and string/M-theory contexts, including enlarged superspace algebras and FDA formulations. The method broadens the landscape of symmetry algebras accessible from a given starting point and offers new avenues for constructing actions based on expanded gauge algebras.
Abstract
We study how to generate new Lie algebras $\mathcal{G}(N_0,..., N_p,...,N_n)$ from a given one $\mathcal{G}$. The (order by order) method consists in expanding its Maurer-Cartan one-forms in powers of a real parameter $λ$ which rescales the coordinates of the Lie (super)group $G$, $g^{i_p} \to λ^p g^{i_p}$, in a way subordinated to the splitting of $\mathcal{G}$ as a sum $V_0 \oplus ... \oplus V_p \oplus ... \oplus V_n$ of vector subspaces. We also show that, under certain conditions, one of the obtained algebras may correspond to a generalized İnönü-Wigner contraction in the sense of Weimar-Woods, but not in general. The method is used to derive the M-theory superalgebra, including its Lorentz part, from $osp(1|32)$. It is also extended to include gauge free differential (super)algebras and Chern-Simons theories, and then applied to D=3 CS supergravity.
