Quantum simulation of exact electron dynamics can be more efficient than classical mean-field methods
Abstract Quantum algorithms for simulating electronic ground states are slower than popular classical mean-field algorithms such as Hartree–Fock and density functional theory but offer higher accuracy. Accordingly, quantum computers have been predominantly regarded as competitors to only the most ac...
| Main Authors: | , , , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Nature Portfolio
2023-07-01
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| Series: | Nature Communications |
| Online Access: | https://doi.org/10.1038/s41467-023-39024-0 |
| _version_ | 1797778830967963648 |
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| author | Ryan Babbush William J. Huggins Dominic W. Berry Shu Fay Ung Andrew Zhao David R. Reichman Hartmut Neven Andrew D. Baczewski Joonho Lee |
| author_facet | Ryan Babbush William J. Huggins Dominic W. Berry Shu Fay Ung Andrew Zhao David R. Reichman Hartmut Neven Andrew D. Baczewski Joonho Lee |
| author_sort | Ryan Babbush |
| collection | DOAJ |
| description | Abstract Quantum algorithms for simulating electronic ground states are slower than popular classical mean-field algorithms such as Hartree–Fock and density functional theory but offer higher accuracy. Accordingly, quantum computers have been predominantly regarded as competitors to only the most accurate and costly classical methods for treating electron correlation. However, here we tighten bounds showing that certain first-quantized quantum algorithms enable exact time evolution of electronic systems with exponentially less space and polynomially fewer operations in basis set size than conventional real-time time-dependent Hartree–Fock and density functional theory. Although the need to sample observables in the quantum algorithm reduces the speedup, we show that one can estimate all elements of the k-particle reduced density matrix with a number of samples scaling only polylogarithmically in basis set size. We also introduce a more efficient quantum algorithm for first-quantized mean-field state preparation that is likely cheaper than the cost of time evolution. We conclude that quantum speedup is most pronounced for finite-temperature simulations and suggest several practically important electron dynamics problems with potential quantum advantage. |
| first_indexed | 2024-03-12T23:22:11Z |
| format | Article |
| id | doaj.art-52f5615a26b1420493485a106f8d0e49 |
| institution | Directory Open Access Journal |
| issn | 2041-1723 |
| language | English |
| last_indexed | 2024-03-12T23:22:11Z |
| publishDate | 2023-07-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Nature Communications |
| spelling | doaj.art-52f5615a26b1420493485a106f8d0e492023-07-16T11:21:08ZengNature PortfolioNature Communications2041-17232023-07-011411910.1038/s41467-023-39024-0Quantum simulation of exact electron dynamics can be more efficient than classical mean-field methodsRyan Babbush0William J. Huggins1Dominic W. Berry2Shu Fay Ung3Andrew Zhao4David R. Reichman5Hartmut Neven6Andrew D. Baczewski7Joonho Lee8Google Quantum AIGoogle Quantum AIDepartment of Physics and Astronomy, Macquarie UniversityDepartment of Chemistry, Columbia UniversityGoogle Quantum AIDepartment of Chemistry, Columbia UniversityGoogle Quantum AIQuantum Algorithms and Applications Collaboratory, Sandia National LaboratoriesGoogle Quantum AIAbstract Quantum algorithms for simulating electronic ground states are slower than popular classical mean-field algorithms such as Hartree–Fock and density functional theory but offer higher accuracy. Accordingly, quantum computers have been predominantly regarded as competitors to only the most accurate and costly classical methods for treating electron correlation. However, here we tighten bounds showing that certain first-quantized quantum algorithms enable exact time evolution of electronic systems with exponentially less space and polynomially fewer operations in basis set size than conventional real-time time-dependent Hartree–Fock and density functional theory. Although the need to sample observables in the quantum algorithm reduces the speedup, we show that one can estimate all elements of the k-particle reduced density matrix with a number of samples scaling only polylogarithmically in basis set size. We also introduce a more efficient quantum algorithm for first-quantized mean-field state preparation that is likely cheaper than the cost of time evolution. We conclude that quantum speedup is most pronounced for finite-temperature simulations and suggest several practically important electron dynamics problems with potential quantum advantage.https://doi.org/10.1038/s41467-023-39024-0 |
| spellingShingle | Ryan Babbush William J. Huggins Dominic W. Berry Shu Fay Ung Andrew Zhao David R. Reichman Hartmut Neven Andrew D. Baczewski Joonho Lee Quantum simulation of exact electron dynamics can be more efficient than classical mean-field methods Nature Communications |
| title | Quantum simulation of exact electron dynamics can be more efficient than classical mean-field methods |
| title_full | Quantum simulation of exact electron dynamics can be more efficient than classical mean-field methods |
| title_fullStr | Quantum simulation of exact electron dynamics can be more efficient than classical mean-field methods |
| title_full_unstemmed | Quantum simulation of exact electron dynamics can be more efficient than classical mean-field methods |
| title_short | Quantum simulation of exact electron dynamics can be more efficient than classical mean-field methods |
| title_sort | quantum simulation of exact electron dynamics can be more efficient than classical mean field methods |
| url | https://doi.org/10.1038/s41467-023-39024-0 |
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