Researchers resolved the apparent paradox between quantum mechanics and classical thermodynamics by demonstrating that while von Neumann entropy remains constant in quantum systems, Shannon entropy increases over time just as classical entropy does, thereby reconciling quantum theory with the second law of thermodynamics.
When two microscopic systems are entangled, their properties are linked to each other irrespective of the physical distance between the two. Manipulating this uniquely quantum phenomenon is what allows for quantum cryptography, communication, and computation. While parallels have been drawn between quantum entanglement and the classical physics of heat, new research demonstrates the limits of this comparison. Entanglement is even richer than we have given it credit for.