I was wondering how to do the following
$\epsilon_{ijk}\sigma_{jk}=\epsilon_{iji}=0$
I get this is $0$ but don't understand how they got the $\epsilon_{iji}$
I was wondering how to do the following
$\epsilon_{ijk}\sigma_{jk}=\epsilon_{iji}=0$
I get this is $0$ but don't understand how they got the $\epsilon_{iji}$
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We have $\epsilon_{ijk}\delta_{jk}=\epsilon_{ijj}=\epsilon_{jij}$, where the second $=$ uses cyclic invariance. The statements $\epsilon_{iji}=0,\,\epsilon_{jij}=0$ are really the same statement twice, differently indexed. Any source that wrote $\epsilon_{ijk}\delta_{jk}=\epsilon_{iji}$ has effected an $i\leftrightarrow j$ relabelling, which shouldn't have been done, not least because it changes which index isn't contracted.