Executive Summary : | The development of quantum theory and information theory for communication have led to significant advancements in computing and communication protocols over the past three decades. Primitive quantum protocols include teleportation, entanglement distribution, quantum key distribution, and Shor's algorithm for prime factorisation. Quantum information theory allows for the distribution of secret keys with unconditional security among trusted users against quantum eavesdroppers, who may have unbounded computational power but are limited only by physical laws. However, the continuous interaction of quantum systems with the surrounding environment poses a major concern. The project aims to study fundamental limitations on the quantum Internet, networks of users who may possess quantum computers and perform quantum communication over channels alongside traditional computing and communication. The project will determine the costs required to prepare quantum states and simulate quantum channels of demand, which are crucial for building the quantum Internet. The project will also introduce figures of merit to assess the robustness and efficiency of the underlying network architecture and topologies for near-term and futuristic quantum Internet. These figures will provide a benchmark for experimentalists to compare different components to make optimal choices in architecture and quantum systems and channels. Understanding the desired quantum correlations generating capabilities of quantum processes is also important, as nonlocality is a necessary quantum correlation for quantum cryptography in scenarios where users cannot trust devices. This proposal has implications on both the fundamental and applied aspects of the quantum Internet. |