The proposed equivalence is false. On a nonzero vector space over any field of characteristic different from two, choose
These linear projections commute and satisfy . Nevertheless their sum is , and
Thus the proposed conditions are not sufficient. For commuting linear projections the actual obstruction is the sum of the pairwise products:
The single condition on the triple product does not remove this obstruction.

Articles by others on the same topic (0)

There are currently no matching articles.