Any time two entities interact, they entangle. It doesn’t matter if they are photons (bits of light), atoms (bits of matter), or bigger things made of atoms like dust motes, microscopes, cats or people. The entanglement persists no matter how far these entities separate, as long as they don’t subsequently interact with anything else – an almost impossibly tall order for a cat or a person, which is why we don’t notice the effect. But the motions of subatomic particles are dominated by entanglement. It starts when they interact; in doing so, they lose their separate existence. No matter how far they move apart, if one is tweaked, measured, observed, … Continue reading Entanglement (Louisa Gilder)