Affine Lie algebras of sl_2

Twisted vertex operator representation of 𝔰𝔩2𝕂ˆ

Let ˆ𝔞1 =𝔰𝔩2𝕂ˆ[𝜎1] be the [[Affine Lie algebras of sl_2|𝜎1-twisted affine Lie algebra of 𝔰𝔩2𝕂]], and 𝑉 be the corresponding [[Natural Heisenberg algebras| +12-natural Heisenberg module]] on 𝔥 =𝕂𝛼. Defining

𝛼(𝑧)±=𝑛±(0+12)𝛼(𝑛)𝑧𝑛𝛼(𝑧)=𝑛+12𝛼(𝑛)𝑧𝑛=𝛼(𝑧)++𝛼(𝑧)𝐸±(𝛼,𝑧)=e𝐷1𝛼(𝑧)±

we construct the twisted vertex operator

𝑋+12(𝛼,𝑧)=𝐸(𝛼,𝑧)𝐸+(𝛼,𝑧)2𝛼,𝛼=:e𝐷1𝛼(𝑧):2𝛼,𝛼

where the second expression used the Normal ordered product. Skipping over a lot of detail1, the representation of ˜𝔥[ 1] on 𝑉 extends to precisely two irreducible representations

𝜋±:˜𝔞1End𝑉𝑥𝛼1(𝑧)𝑋(𝛼1,𝑧)


develop | en | SemBr

Footnotes

  1. 1988. Vertex operator algebras and the Monster, §3, pp. 61ff.