The vast emptiness of space grows even more headache-inducing if one entertains the possibility of “spooky actions at a distance,” Albert Einstein’s dismissive term for the effects of quantum entanglement. Scientists have proven many times over that entangled particles somehow “know” certain basic physical properties of their other half, even when they are separated by light-years. This is a purely quantum mechanical phenomenon, one that classical physics is unable to explain without a “hidden variable,” some heretofore unmeasured and unnoticed quality of our universe that would allow classical physics to explain entanglement without the trouble of quantum theory.
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