Robert Foot also interpreted the Koide formula as a geometrical relation, in which the value 1 3 Q is the squared cosine of the angle between the vector [ m e , m μ μ , m τ τ ] and the vector [ 1 , 1 , 1 ] (see dot product). That angle is almost exactly 45 degrees: θ θ = 45.000 ∘ ∘ ± ± 0.001 ∘ ∘ .