Definition talk:Connection Coefficients

Implied summation

In practice, Einstein summation convention is used quite often both in physics and in maths, definitely when multiple contractions are involved. On the other hand, for the first encounter this may indeed look too cryptic - which indices are we really summing over? In that case at least for definitions we could actually provide both explicit and implicit options because we do have space.--Julius (talk) 20:08, 28 September 2022 (UTC)

Yes, there are many conventions, e.g. some people put only $\sum$ or $\sum_k$. But IMHO at least the definitions should be written, correctly. --Usagiop (talk) 20:29, 28 September 2022 (UTC)

Well, Einstein summation convention simply ommits $\ds \Sigma$. The other extreme requires writing out everything. In a place like this I would either use either Einstein (with sufficiently detailed description on its page) or explicit conventions. Intermediate cases better to be left to books or personal notes.--Julius (talk) 21:26, 28 September 2022 (UTC)