Preparing ground states of quantum many-body systems on a quantum computer

TL;DR

This paper demonstrates that quantum computers can efficiently prepare ground states of quantum many-body systems, extending classical results and showing potential for solving complex quantum problems more efficiently.

Contribution

It extends the known quantum speedup for classical systems to interacting quantum particles, showing quantum computers can prepare ground states efficiently.

Findings

Quantum computers can prepare ground states of quantum systems in sqrt(N) time.

The method generalizes classical ground state preparation to quantum many-body systems.

Provides a theoretical foundation for quantum advantage in simulating quantum systems.

Abstract

Preparing the ground state of a system of interacting classical particles is an NP-hard problem. Thus, there is in general no better algorithm to solve this problem than exhaustively going through all N configurations of the system to determine the one with lowest energy, requiring a running time proportional to N. A quantum computer, if it could be built, could solve this problem in time sqrt(N). Here, we present a powerful extension of this result to the case of interacting quantum particles, demonstrating that a quantum computer can prepare the ground state of a quantum system as efficiently as it does for classical systems.