A Jordan algebra𝐽 over 𝕂 is commutative non-associative algebra with a symmetric bilinear product {−,−}:𝐽×𝐽→𝐽 satisfying the Jordan identity#m/def/ralg
{{𝑥,𝑦},{𝑥,𝑥}}={𝑥,{𝑦,{𝑥,𝑥}}}
The quintessential example is the Anticommutator of a 𝕂-monoid,
usually renormalized so that {𝑥,𝑥}=𝑥2.
We denote the anticommutator algebra by 𝐴+ and the renormalized one as 𝐴+1/2.