Structurable algebra

In abstract algebra, a structurable algebra is a certain kind of unital involutive non-associative algebra over a field. For example, all Jordan algebras are structurable algebras (with the trivial involution), as is any alternative algebra with involution, or any central simple algebra with involution. An involution here means a linear anti-homomorphism whose square is the identity.

Assume A is a unital non-associative algebra over a field, and is an involution. If we define , and , then we say A is a structurable algebra if: