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Physics

Entangled Particles

Quick fact

When two particles become entangled, their properties (like spin) are not individually defined until one is measured—then the other's state is instantaneously determined, even if they are light-years apart.

Why this is interesting

Imagine flipping two coins on opposite sides of the world—if one lands heads, the other instantly becomes tails. This “spooky” link is real for entangled particles, and it challenges our everyday sense of reality.