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arXiv · hep-th/0304257

Superconformal mechanics and nonlinear supersymmetry

Carlos Leiva·Mikhail S. Plyushchay
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Abstract

We show that a simple change of the classical boson-fermion coupling constant, $2α\to 2αn $, $n\in \N$, in the superconformal mechanics model gives rise to a radical change of a symmetry: the modified classical and quantum systems are characterized by the nonlinear superconformal symmetry. It is generated by the four bosonic integrals which form the so(1,2) x u(1) subalgebra, and by the 2(n+1) fermionic integrals constituting the two spin-n/2 so(1,2)-representations and anticommuting for the order n polynomials of the even generators. We find that the modified quantum system with an integer value of the parameter $α$ is described simultaneously by the two nonlinear superconformal symmetries of the orders relatively shifted in odd number. For the original quantum model with $|α|=p$, $p\in \N$, this means the presence of the order 2p nonlinear superconformal symmetry in addition to the osp(2|2) supersymmetry.

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Carlos Leiva, Mikhail S. Plyushchay. 2003-11-08. Superconformal mechanics and nonlinear supersymmetry. https://doi.org/10.1088/1126-6708%2F2003%2F10%2F069

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