Quantum Simulation of Field Theories Without State Preparation

Understand

We propose an algorithm for computing real-time observables using a quantum processor while avoiding the need to prepare the full quantum state.

• This reduction in quantum resources is achieved by classically sampling configurations in imaginary-time using standard lattice field theory.
• These configurations can then be passed to quantum processor for time-evolution.
• This method encounters a signal-to-noise problem which we characterize, and we demonstrate the application of standard lattice QCD methods to mitigate it.