American physicist, co-author of the GHZ state. He made significant contributions to quantum optics and quantum measurements, including the formulation of Bell's theorem with multiple observers and pioneering experiments on interference and entanglement.
Biography
He received his PhD from Boston University. He worked at the Massachusetts Institute of Technology and Stonehill College, where he combined teaching with research. He worked closely with Anton Zeilinger and Daniel Greenberger.
Key discoveries
GHZ state: together with Greenberger and Zeilinger, proposed the state and proved its nonlocal properties (1989).
Multipartite Bell inequalities: developed generalizations of the inequalities for multiple observers, expanding the understanding of nonlocality.
Entangled-state interferometry: participated in experiments demonstrating quantum advantage in measurement precision.
💡 Horne is known for his wit: at conferences, he often illustrates quantum paradoxes with coin tricks. His co-author Zeilinger won the Nobel Prize for developing GHZ ideas.
Quote: ""Reality is not made of parts until we ask it about that — and even then it surprises us.""
Physicists have found a way to bring a large magnet into a quantum state where it spins both clockwise and counterclockwise at once. This split gives unimaginable precision for detecting weak magnetic fields. The main obstacle is collisions with air molecules, but a carefully chosen shape and a vacu