An exploration of quantum entanglement and the ways in which it contradicts our everyday
assumptions about the ultimate nature of reality. Quantum physics is notable for its brazen
defiance of common sense. (Think of Schrödinger's Cat famously both dead and alive.) An
especially rigorous form of quantum contradiction occurs in experiments with entangled
particles. Our common assumption is that objects have properties whether or not anyone is
observing them and the measurement of one can't affect the other. Quantum entanglement—called
by Einstein spooky action at a distance”—rejects this assumption offering impeccable reasoning
and irrefutable evidence of the opposite. Is quantum entanglement mystical or just mystifying?
In this volume in the MIT Press Essential Knowledge series Jed Brody equips readers to decide
for themselves. He explains how our commonsense assumptions impose constraints—from which
entangled particles break free. Brody explores such concepts as local realism Bell's
inequality polarization time dilation and special relativity. He introduces readers to
imaginary physicists Alice and Bob and their photon analyses points out that it's easier to
reject falsehood than establish the truth and reports that some physicists explain
entanglement by arguing that we live in a cross-section of a higher-dimensional reality. He
examines a variety of viewpoints held by physicists including quantum decoherence Niels
Bohr's Copenhagen interpretation genuine fortuitousness and QBism. This relatively recent
interpretation an abbreviation of quantum Bayesianism ” holds that there's no such thing as an
absolutely accurate objective probability out there ” that quantum mechanical probabilities
are subjective judgments and there's no action at a distance ” spooky or otherwise.
