PauliChainJoin[exp]
joins chains of Pauli matrices with explicit Pauli indices wrapped with a head PauliChain
.
Overview, PauliChain, PCHN, PauliIndex, PauliIndexDelta, DIDelta, PauliChainCombine, PauliChainExpand, PauliChainFactor.
[PauliXi[-I], i] PCHN[CSID[a] . CSID[b], i, j] PCHN[j, PauliEta[I]]
PCHN
[%] PauliChainJoin
(\eta )_j \left(\xi ^{\dagger }\right){}_i \left(\sigma ^a.\sigma ^b\right){}_{ij}
\xi ^{\dagger }.\sigma ^a.\sigma ^b.\eta