ScalingStacks

Definition 1.5. A co-$t$-structure $(𝒜,ℬ)$ on a triangulated category $𝒯$ will be called non-degenerate if we have

$$\bigcap _{n\in \mathbb{Z}}{\mathrm{\Sigma }}^n𝒜=\bigcap _{n\in \mathbb{Z}}{\mathrm{\Sigma }}^nℬ=\{0\}.$$