PyTorch simulator refutes an 18-year-old quantum theorem (github.com)

A groundbreaking analysis using PyTorch has effectively disproven the 18-year-old Smith-Yard superactivation hypothesis in quantum mechanics, which posited that bound entangled states could enable increased communication capacity. Researchers employed advanced computational techniques, including exact Stinespring purifications and a hybrid AI simulation, to navigate a complex 512-dimensional Positive Partial Transpose (PPT) manifold. Their findings revealed that Horodecki private states cannot establish a positive key rate, undermining the viability of quantum one-time pad protocols by revealing significant leakage to the environment. The implications of this research are profound for the AI and quantum computing communities. By utilizing high-precision global optimization methods, including Basin Hopping and Adam, alongside a 30-qubit machine learning simulator named QuantumOS, the study demonstrated that even with idealized conditions—such as foreknowledge of classical Erasure Flags—the system ultimately failed to achieve positive capacity, hitting a “Barren Plateau.” This not only challenges previously held beliefs about quantum superactivation but also emphasizes the limitations of quantum communication under current theoretical frameworks, presenting new avenues for exploration in quantum information theory.