Characterizing Quantum Supremacy in Near-Term Devices · HackerPapers discussions

Characterizing Quantum Supremacy in Near-Term Devices — mentioned by tagrun

Mon, 23 Sep 2019 23:18:58 GMT

- Cross-entropy is used for roughly estimating the fidelity (see arXiv:1608.00263), which is independent of the problem they're solving. You're confusing it with the overall distribution of the readout states, which is the hard problem. - CZ is a perfect entangler. No, iSWAP and CZ do not form a universal set. They typically combine virtual Z rotations (which has a continuous angle parameter) with an additional one-qubit gate, such as a X or Y gate (or their square root, which they mention in the paper) which gives a universal set. Although they don't make use of continuous Z rotations in…

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Characterizing Quantum Supremacy in Near-Term Devices — mentioned by comnetxr

Sun, 22 Sep 2019 21:50:45 GMT

I'm not an expert, but you are correct in that there is no error correction here, and error correction is still a long way off. Around 2016, realizing that running useful quantum algorithms was a long way away and there needed to be earlier roadmarks for quantum devices to signal the progress, the problem of "quantum supremacy" was introduced. The goal is to find the problem with the _easiest_ demonstrable quantum speedup (regardless of usefulness). They proposed a particular sampling problem (running a randomly chosen quantum circuit that has output with a positive probability on many…

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Characterizing Quantum Supremacy in Near-Term Devices — mentioned by adrianN

Fri, 07 Sep 2018 19:01:59 GMT

The keyword to google for here is "quantum supremacy". There is for example this paper https://arxiv.org/abs/1608.00263

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Characterizing Quantum Supremacy in Near-Term Devices — HN submission

Mon, 07 May 2018 14:47:43 GMT

Characterizing Quantum Supremacy in Near-Term Devices

1 point; 0 discussion replies on HN. Paper and source history. A submission is not an endorsement.

Characterizing Quantum Supremacy in Near-Term Devices — mentioned by ivan_ah

Fri, 04 May 2018 22:15:44 GMT

The arXiv links: - https://arxiv.org/abs/1608.00263 - https://arxiv.org/abs/1709.06678

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Characterizing Quantum Supremacy in Near-Term Devices — mentioned by avz

Sun, 11 Jun 2017 15:17:32 GMT

I believe they talk about the computational task described in [1] (published in 2016). Note that this is somewhat contrived: it's a task defined specifically so that it is very difficult for classical computers and relatively easy for quantum computers. It is also defined in a way that ensures that a quantum computer necessary to demonstrate quantum supremacy is relatively small in terms of the number of qubits. The task is that of generating output samples from pseudo-random quantum circuits. The paper shows that the task has exponential computational complexity on classical computers and…

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Characterizing Quantum Supremacy in Near-Term Devices — mentioned by johncolanduoni

Sat, 22 Apr 2017 14:50:48 GMT

If you want to read the paper laying out the plan the article is referring to, it's here: https://arxiv.org/abs/1608.00263

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Characterizing Quantum Supremacy in Near-Term Devices — mentioned by Strilanc

Sun, 22 Jan 2017 00:43:42 GMT

> there are also no real signs that a quantum computer will beat a "classical" computer at anything any time soon John Martinis' group is planning to do that within the next two years [1][2]. Ten years might be realistic for solving useful problems faster and cheaper, but the esoteric speedups are right around the corner. 1: https://arxiv.org/abs/1608.00263 2: https://www.youtube.com/watch?v=kgMWommXxU8

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