Is Fault-Tolerant Quantum Computation Really Possible?

Abstract

The so-called "threshold" theorem says that, once the error rate per qubit per gate is below a certain value, indefinitely long quantum computation becomes feasible, even if all of the qubits involved are subject to relaxation processes, and all the manipulations with qubits are not exact. The purpose of this article, intended for physicists, is to outline the ideas of quantum error correction and to take a look at the proposed technical instruction for fault-tolerant quantum computation. It seems that the mathematics behind the threshold theorem is somewhat detached from the physical reality, and that some ideal elements are always present in the construction. This raises serious doubts about the possibility of large scale quantum computations, even as a matter of principle.

Based on a talk given at the Future Trends in Microelectronics workshop, Crete, June 2006. 8 pages, 1 figure

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Cited by in corpus (10)

• Non-Abelian Anyons and Topological Quantum Computation
• Warm-Starting and Quantum Computing: A Systematic Mapping Study
• Superradiance as a Source of Collective Decoherence in Quantum Computers
• The Quantum Computer Puzzle (Expanded Version)
• The Last Scientific Revolution
• Sufficient condition on noise correlations for scalable quantum computing
• Quantum memory as a perpetuum mobile? Stability v.s. reversibility of information processing
• Prospects for Quantum Computing
• Quantum memories and Landauer's principle
• Large Sample Superradiance and Fault-Tolerant Quantum Computation