Special Relativity Spacetime Lab

Special relativity made physical. A rod-train moves at speed $\beta = v/c$ and is Lorentz-contracted to $L_0/\gamma$ against its dashed rest length, while two twin clocks tick: on a round trip the travelling twin returns having aged only $2L/(\gamma\beta)$ against the stay-home $2L/\beta$. The side panel is the Minkowski diagram with the 45-degree light cone, the boosted lines of simultaneity, and the bent twin worldline.

Figure 1. Lorentz contraction, the desynchronising twin clocks, the contraction ratio, the Minkowski worldlines, and a textual reading.

WHAT TO TRY

Vary each control and watch the rail readouts respond.
Compare the diagnostic plot against the live scene.