Definition 10.2.6 (Stable spherical fibration). Let \(\Pic (\S ) \subseteq \Sp ^{\simeq }\) denote the full subcategory spanned by shifts \(\S [n]\) of the sphere spectrum. For an anima \(A\), we define a stable spherical fibration on \(A\) to be a functor \(\xi \colon A \to \Sp \) which lands in \(\Pic (\S )\). For an integer \(n \in \Z \) we say that \(\xi \) has rank \(n\) if it in fact lands in the full subanima of \(\Pic (\S )\) spanned by \(\S [n]\).
Generated from the authoritative LaTeX source.