A new N = 8 nonlinear supermultiplet

TL;DR

This paper introduces a new off-shell nonlinear supermultiplet with N=8 supersymmetry in one dimension, derived from a superconformal group, and explores its actions and relations to other supermultiplets.

Contribution

The paper constructs a novel nonlinear supermultiplet from superconformal symmetry and derives its general sigma-model action, expanding the understanding of N=8 supersymmetric models.

Findings

Constructed a new off-shell nonlinear supermultiplet ((4,8,4))

Derived the most general sigma-model type action for this supermultiplet

Explored relations between linear and nonlinear supermultiplets and vector supermultiplets.

Abstract

We construct a new off-shell $\mathcal{N}{=}8$, $d{=}1$ nonlinear supermultiplet $(\mathbf{4,8,4})$ proceeding from the nonlinear realization of the $\mathcal{N}{=}8$, $d{=}1$ superconformal group $OSp(4^{\star}|4)$ in its supercoset $\frac{OSp(4^{\star}|4)}{SU(2)_{\mathcal{R}}\otimes \left\{D,K\right\} \otimes SO(4)}$. The irreducibility constraints for the superfields automatically follow from appropriate covariant conditions on the $osp(4^{\star}|4)$-valued Cartan superforms. We present the most general sigma-model type action for $(\mathbf{4,8,4})$ supermultiplet. The relations between linear and nonlinear $(\mathbf{4,8,4})$ supermultiplets and linear $\mathcal{N}{=}8$ $(\mathbf{5,8,3})$ vector supermultiplet are discussed.