Spin .....Dr. Riemann......the square root of 3 equil triangle is the smallest that can be inscribed in the unit circle......a 2times the square root of 3 triangle is the smallest to inscribe the unit circle....inside outside......the torus has turned itself completely inside out in the 4d............symmetry Emily N........

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Unit circle

In mathematics, a unit circle is a circle with a radius of one. Frequently, especially in trigonometry, the unit circle is the circle of radius one centered at the origin in the Cartesian coordinate system in the Euclidean plane. Wikipedia