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92 experiments / 15 branches

THE LIGHT POSTULATE

Every inertial observer measures light at exactly c — and everything else bends to accommodate it.

LIGHT CLOCK

One postulate, one right triangle — and time itself gives way. γ = 1.25, bitwise.

5 STAGES · 8 TERMS

TWINS

τ² = 5² − 4² = 3² — a Pythagorean triple in spacetime, and a paradox with balanced books.

5 STAGES · 8 TERMS

E = mc²

E² − (pc)² = (mc²)², residual zero — and a collision that CREATES mass.

5 STAGES · 8 TERMS

MUONS

One in ten billion should arrive. A hundred do. The sky votes for relativity.

5 STAGES · 8 TERMS

DOPPLER (SR)

At 0.6c the light ahead exactly doubles — and abeam, time dilation shows its bare face.

5 STAGES · 8 TERMS

THEORY IN PLAY — Interactive Physics ·

Pause at stages ←→ step · PgUp/Dn stage · Space play

Speed Loop scene

Given

Computed