English
Rotating the second vector scales Kahler form by the angle θ: o.kahler x (o.rotation θ y) = θ.toCircle o.kahler x y.
Русский
Поворот второго вектора на θ масштабирует Kahler форму на θ: o.kahler x (o.rotation θ y) = θ.toCircle o.kahler x y.
LaTeX
$$$ o.kahler x (o.rotation(\theta) y) = \theta.toCircle \cdot o.kahler x y $$$
Lean4
/-- Rotating the second of two vectors by `θ` scales their Kähler form by `cos θ + sin θ * I`. -/
@[simp]
theorem kahler_rotation_right (x y : V) (θ : Real.Angle) : o.kahler x (o.rotation θ y) = θ.toCircle * o.kahler x y :=
by
simp only [o.rotation_apply, map_add, LinearMap.map_smulₛₗ, RingHom.id_apply, real_smul,
kahler_rightAngleRotation_right, Real.Angle.coe_toCircle]
ring