# Classical Simulation of Quantum Supremacy Circuits

@article{Huang2020ClassicalSO, title={Classical Simulation of Quantum Supremacy Circuits}, author={Cupjin Huang and Fang Zhang and Michael Newman and Junjie Cai and Xun Gao and Zhengxiong Tian and Junyin Wu and Haihong Xu and Huanjun Yu and Bo Yuan and Mario Szegedy and Yaoyun Shi and Jianxin Chen}, journal={arXiv: Quantum Physics}, year={2020} }

It is believed that random quantum circuits are difficult to simulate classically. These have been used to demonstrate quantum supremacy: the execution of a computational task on a quantum computer that is infeasible for any classical computer. The task underlying the assertion of quantum supremacy by Arute et al. (Nature, 574, 505--510 (2019)) was initially estimated to require Summit, the world's most powerful supercomputer today, approximately 10,000 years. The same task was performed on the…

## 58 Citations

### Boundaries of quantum supremacy via random circuit sampling

- Physics, Computer Science
- 2020

The constraints of the observed quantum runtime advantage in an analytical extrapolation to circuits with a larger number of qubits and gates are examined, suggesting the boundaries of quantum supremacy via random circuit sampling may fortuitously coincide with the advent of scalable, error corrected quantum computing in the near term.

### Statistical Aspects of the Quantum Supremacy Demonstration

- Physics, Computer ScienceStatistical Science
- 2022

The relations between quantum computing and some of the statistical aspects involved in demonstrating quantum supremacy are explained in terms that are accessible to statisticians, computer scientists, and mathematicians.

### Leveraging State Sparsity for More Efficient Quantum Simulations

- Computer ScienceACM Transactions on Quantum Computing
- 2022

This work is the first to fully simulate a quantum algorithm to compute elliptic curve discrete logarithms, and its prototype implementation includes optimizations such as gate (re)scheduling, which amortizes data structure accesses and reduces memory usage.

### Simulation Paths for Quantum Circuit Simulation with Decision Diagrams

- Computer ScienceIEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems
- 2022

It is shown, conceptually and experimentally, that choosing the right simulation path can make a vast difference in the efﬁciency of classical simulations using decision diagrams and a dedicated simulation path heuristic is designed that allows to improve the performance even further— frequently yielding speedups of several orders of magnitude.

### Improved robustness of quantum supremacy for random circuit sampling

- Computer Science
- 2021

It is proved under the complexity theoretical assumption of the non-collapse of the polynomial hierarchy that approximating the output probabilities of random quantum circuits to within exp(−Ω(m logm)) additive error is hard for any classical computer, where m is the number of gates in the quantum computation.

### Comparative Study of Sampling-Based Simulation Costs of Noisy Quantum Circuits

- PhysicsPhysical Review Applied
- 2021

This work improves the existing stabilizer-state sampling algorithm based on robustness of magic so that the simulation costs of noisy quantum circuits are reduced even under noise on Clifford gates, and calculates the simulation Costs of a noisy single-qubit rotation gate and confirmed that small noise makes the noisy rotation gate efficiently simulatable, as expected.

### How to Simulate Quantum Measurement without Computing Marginals.

- Computer SciencePhysical review letters
- 2022

Algorithms for classically simulating measurement of an n-qubit quantum state in the standard basis, that is, sampling a bit string from the probability distribution determined by the Born rule are described and analyzed.

### Quantum supremacy and hardness of estimating output probabilities of quantum circuits

- Computer Science2021 IEEE 62nd Annual Symposium on Foundations of Computer Science (FOCS)
- 2022

It is proved under the complexity theoretical assumption of the non-collapse of the polynomial hierarchy that approximating the output probabilities of random quantum circuits to within $\exp(-\Omega(m\log m))$ additive error is hard for any classical computer, where $m$ is the number of gates in the quantum computation.

### Closing the “Quantum Supremacy” Gap: Achieving Real-Time Simulation of a Random Quantum Circuit Using a New Sunway Supercomputer

- Computer ScienceSC21: International Conference for High Performance Computing, Networking, Storage and Analysis
- 2021

A high-performance tensor-based simulator for random quantum circuits(RQCs) on the new Sunway supercomputer, which effectively expands the scope of simulatable RQCs to include the 10×10(qubits)X(1 + 40 + l)(depth) circuit, with a sustained performance of 1.2 Eflops.

### A quantum circuit simulator and its applications on Sunway TaihuLight supercomputer

- Physics, Computer ScienceScientific reports
- 2021

A new quantum circuit simulator developed on the Sunway TaihuLight supercomputer is presented that is more versatile and of high efficiency, and is expected to have broader applications in developing quantum algorithms in various fields.

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