Direct sum is not the coproduct in the category of quadratic vector spaces. The absence of terminal objects and (co)products in QVec is due to the fact that projections do not generally preserve norms.
José Figueroa O'Farrill, Spin Geometry

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Direct sum is not the coproduct in the category of quadratic vector spaces. The absence of terminal objects and (co)products in QVec is due to the fact that projections do not generally preserve norms.
José Figueroa O'Farrill, Spin Geometry