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Free Boson Representation of $DY_{\hbar}(sl_2)_k$ and the Deformation of the Feigin-Fuchs

X. M. Ding·L. Zhao
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Abstract

A realization of the Yangian double with center $DY_\hbar(sl_2)_k$ of level $k(\not=0,-2)$ in terms of free boson fields is constructed. The screening currents are also presented, which commute with $DY_\hbar(sl_2)$ modulo total difference. In the $\hbar\to 0$ limit, the currents of Yangian double $DY_\hbar(sl_2)_k$ becomes the Feigin-Fuchs realization of affine Lie $sl(2)_k$, while the screening currents of Yangian double $DY_\hbar(sl_2)_k$ becomes the screening currents of the affine Lie algebra $sl(2)_k$.

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X. M. Ding, L. Zhao. 1997-10-14. Free Boson Representation of $DY_{\hbar}(sl_2)_k$ and the Deformation of the Feigin-Fuchs. https://arxiv.org/abs/hep-th/9710106

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