Perpendicular-Boost Wigner Rotation

Two perpendicular positive-rapidity boosts a and b create a spatial rotation known as Wigner Rotation. The rotation magnitude is Ω = 2 arctan(tanh(a/2) tanh(b/2)).

experiment

Use the interactive module to set the first and second rapidity and observe the Wigner rotation. We will trace how changing inputs affect the rotation axis. You can find the module at the Interactive Module link.

1. Set the first rapidity control to exactly 1 to configure the primary boost along the x-axis.
2. Set the second rapidity control to exactly 1 to configure the secondary boost, and observe the rotation arc.