# The Argument against Quantum Computers

@article{Kalai2019TheAA, title={The Argument against Quantum Computers}, author={Gil Kalai}, journal={ArXiv}, year={2019}, volume={abs/1908.02499} }

We give a computational complexity argument against the feasibility of quantum computers. We identify a very low complexity class of probability distributions described by noisy intermediate-scale quantum computers, and explain why it will allow neither good-quality quantum error-correction nor a demonstration of “quantum supremacy.” Some general principles governing the behavior of noisy quantum systems are derived. Our work supports the “physical Church thesis” studied by Pitowsky (lyuun…

## 17 Citations

### The Argument against Quantum Computers, the Quantum Laws of Nature, and Google's Supremacy Claims

- PhysicsArXiv
- 2020

A computational complexity argument against the feasibility of quantum computers was described, which identified a very low-level complexity class of probability distributions described by noisy intermediate-scale quantum computers, and explained why it would allow neither good-quality quantum error-correction nor a demonstration of "quantum supremacy".

### Quantum Computers, Predictability, and Free Will

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### Concerns About Recent Claims of a Huge Quantum Computational Advantage via Gaussian Boson Sampling ∗

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- 2021

A polynomial-time algorithm from the 2014 paper [15] that may achieve similar or better sampling quality for the statistical methods of [28] is pointed out, based on taking a truncated Fourier–Hermite expansion on the Boson Sampling distribution.

### Conjecture C Still Stands

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More than ten years ago the author described a parameter K ( ρ ) for the complexity of n -qubit quantum state ρ and raised the conjecture (referred to as “Conjecture C”) that when this parameter is…

### Quantum Stabilizer Channel for Thermalization

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### Google's Quantum Supremacy Claim: Data, Documentation, and Discussion

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### Learning classical readout quantum PUFs based on single-qubit gates

- Computer Science, PhysicsQuantum Machine Intelligence
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### Quantum Error Correction

- Computer Science, PhysicsOxford Research Encyclopedia of Physics
- 2020

In quantum computation, error correction is just one component of fault-tolerant design; other approaches to error mitigation in quantum systems include decoherence-free subspaces, noiseless subsystems, and dynamical decoupling.

### Synergies Between Operations Research and Quantum Information Science

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