Anupam Mazumdar

A tiny diamond, smaller than a dust speck, hovers inside a magnetic trap made of microchips. Inside the crystal is a single defect acting as a beacon. Scientists coax the diamond into being in two places at once, like a magician’s ball that honestly rests under two cups. This isn't just a trick.

Light bends around massive bodies: this has been known since Einstein's time. But what if gravity itself is not a smooth fabric of space but a stream of tiny carrier particles? Then a beam passing near a particle should not just bend but enter into a special quantum relationship with it. This relationship is called entanglement.

A massive nanodiamond inside a quantum interferometer splits in two, pulling itself into two realities. Its gravity — tiny, almost imperceptible — stirs the quantum field of the vacuum, giving rise to coherent clouds of gravitons. These are the gravitational shadows cast by each position of the mass.

Spacetime can be imagined as a tightly stretched fabric. A massive body dents it, guiding light. Rotation twists the fabric into a spiral. Such a gravitational funnel can entangle a passing photon with the very source of rotation — say, a tiny mirror. Quantum entanglement springs up: an invisible thread binding their fates.