@inbook{10.2307/j.ctt7rnjq.23,
ISBN = {9780691118369},
URL = {http://www.jstor.org/stable/j.ctt7rnjq.23},
abstract = {Parisi and Sourlas [269] have suggested that a Grassmann vector space of dimensionncan be interpreted as an ordinary vector space of dimension –n. As we have seen in chapter 13, semisimple Lie groups abound with examples in which ann→ –nsubstitution can be interpreted in this way. An early example was Penrose’s binors [280], reps ofSU(2) =Sp(2) constructed asSO(–2), and discussed here in chapter 14. This is a special case of a general relation betweenSO(n) andSp(–n) established in chapter 13; if symmetrizations and antisymmetrizations are interchanged, reps ofSO(n)},
bookauthor = {Predrag Cvitanović},
booktitle = {Group Theory: Birdtracks, Lie's, and Exceptional Groups},
pages = {218--228},
publisher = {Princeton University Press},
title = {E₇ family and its negative-dimensional cousins},
year = {2008}
}