Bourbaki

Corollary

Tag 066R, permanent. Cite it as [Bourbaki, Tag 066R].

Algebra, chapter III, § 10. Derivations

Let AA be an associative graded algebra. For two homogeneous elements, a,ba, b of AA,

[adε(a),adε(b)]ε=adε([a,b]ε). [\mathrm{ad}_\varepsilon(a), \mathrm{ad}_\varepsilon(b)]_\varepsilon = \mathrm{ad}_\varepsilon([a, b]_\varepsilon).
(25)

It suffices to replace dd by adε(a)\mathrm{ad}_\varepsilon(a) and adε(a)\mathrm{ad}_\varepsilon(a) by adε(b)\mathrm{ad}_\varepsilon(b) in (24).

If deg⁡a=α,deg⁡b=β\deg a = \alpha, \deg b = \beta, formula (25) is equivalent to the following relation for every homogeneous element c∈Ac \in A of degree γ\gamma

εα,γ[a,[b,c]ε]ε+εβ,α[b,[c,a]ε]ε+εγ,β[c,[a,b]ε]ε=0 \varepsilon_{\alpha, \gamma}[a, [b, c]_\varepsilon]_\varepsilon + \varepsilon_{\beta, \alpha}[b, [c, a]_\varepsilon]_\varepsilon + \varepsilon_{\gamma, \beta}[c, [a, b]_\varepsilon]_\varepsilon = 0
called the Jacobi identity.

Bourbaki puts the proof directly after the statement, so what is above is the statement and its proof together.

Cited by

Nothing.

Cites

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Transcribed from the printed edition, 1998, Springer. Not translated.