Delineating the boundary between the computational power of quantum and classical devices

Introduction

This project sets out to assess, make use of, and verify the computational power of realistic quantum devices. It comprehensively identifies quantum simulators and paradigmatic quantum devices that are computationally superior to classical supercomputers, based on presently available or plausible physical architectures.

Quantum Advantage Exploration

In doing so, it explores the fine line that discriminates regimes featuring a quantum advantage from ones that are accessible to efficient classical simulation. This naturally two-pronged approach is concerned with:

1. Novel Classical Simulation Tools

   • Developing tools for seemingly deeply quantum prescriptions.
   • Identifying limitations of variational approaches and quantum simulation schemes.

2. New Applications of Quantum Devices

   • Identifying practically minded applications of quantum devices that exhibit a computational speed-up over classical machines.
   • Exploring potentially game-changing applications emerging for learning tasks.

Methodology

To achieve this goal, the project digs deeply into computer science, which provides sophisticated tools of computational complexity and machine learning. This is instrumental in devising methods for the classical simulation of intricate quantum problems.

At the same time, it draws on the physics of complex systems.

Interdisciplinary Effort

This proposal suggests an interdisciplinary effort by bringing together ideas from:

• Quantum information
• Condensed matter physics
• Complexity theory
• Machine learning
• Tensor network theory
• Methods that are unusual in this context, such as signal processing

Individually, each objective substantially advances the respective field, but it is their combination that will permit a true breakthrough by delineating the delicate boundary between quantum and classical computations of synthetic quantum devices.