For the Killing vector equation, I sometimes see it written in terms of spin connection ω and other times in terms of the affine connection Γ.
More clearly ∇μVν+∇νVμ=0=∂μVν+ΓμνλVλ+∂νVμ+ΓνμλVλ
Another time, you find it satisfying this ∂AVB+∂BVA=ωA,CBVC+ωB,CAVC
What is the difference between the two descriptions?
Answer
Comments to the question (v3):
The vielbein eAμ in the Cartan formalism is an intertwiner gμν = eAμ ηAB eBν
between the curved (pseudo) Riemannian metric gμν and the corresponding flat metric ηAB. Here Greek indices μ,ν,λ,…, are so-called curved indices, while capital Roman indices A,B,C,…, are so-called flat indices. See also this related Phys.SE post.The vielbein eAμ translates the vector field V = Vμ∂μ
with curved components Vμ into flat components VA := eAμVμ.The christoffel symbols Γλ,μν and the spin connection ωABμ can be written in terms of the vielbein eAμ, see Wikipedia for details.
TL;DR: Using the vielbein eAμ as an intertwiner, it is possible to show that OP's various conditions for a Killing vector field are equivalent.
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