For questions about schemes to prove that quantum devices can, at least in principle, be exponentially more efficient than their classical ones. Also often referred to as "quantum computational advantage" or "quantum supremacy". Typical examples are sampling problems such as boson sampling and random circuit sampling.
Questions tagged [quantum-advantage]
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Quantum machine learning after Ewin Tang
Recently, a series of research papers have been released (this, this and this, also this) that provide classical algorithms with the same runtime as quantum machine learning algorithms for the same purpose. From my understanding, the key to all the…
Alex
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Are there problems in which quantum computers are known to provide an exponential advantage?
It is generally believed and claimed that quantum computers can outperform classical devices in at least some tasks.
One of the most commonly cited examples of a problem in which quantum computers would outperform classical devices is…
glS
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What exactly is "Random Circuit Sampling"?
Many people have suggested using "Random Circuit Sampling" to demonstrate quantum supremacy. But what is the precise definition of the "Random Circuit Sampling" problem? I've seen statements like "the task
is to take a random (efficient) quantum…
grok
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When will we know that quantum supremacy has been reached?
The term "quantum supremacy" - to my understanding - means that one can create and run algorithms to solve problems on quantum computers that can't be solved in realistic times on binary computers. However, that is a rather vague definition - what…
blalasaadri
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What does Google's claim of "Quantum Supremacy" mean for the question of BQP vs BPP vs NP?
Google recently announced that they have achieved "Quantum Supremacy": "that would be practically impossible for a classical machine."
Does this mean that they have definitely proved that BQP ≠ BPP ? And if that is the case, what are the…
Alex Kinman
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Did D-Wave show quantum advantage in 2023?
I would like to know your thoughts on whether or not D-Wave has shown a a smoking-gun example of quantum advantage this year. I am genuinely not quite sure what to think, but I believe the answer to this question is important in understanding the…
sheesymcdeezy
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Status of Google's quantum supremacy claim 2022
More than a year ago a couple of scientists made a splash by presenting a classical algorithm that took less than a week to simulate Sycamore's circuits on a small GPU cluster. Also, their simulations produced exact results and not estimates.
This…
MonteNero
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Why exactly are variational algorithms considered promising?
There is obviously a great deal of work happening at the moment on variational quantum algorithms. However, I'm struggling to understand why exactly are they considered promising? Looking through some papers and review articles (such as this one…
Nikita Nemkov
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Why do the IBM and Google processors both have 53 qubits?
As I understand from this IBM post both the IBM and Google teams have independently built 53-qubit processors. What is the significance of the number 53? It is purely coincidental, or is there a deeper reason why both team have the same number of…
Randomblue
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Quantum Supremacy: How do we know that a better classical algorithm doesn't exist?
According to the Wikipedia (Which quotes this paper https://arxiv.org/abs/1203.5813 by Preskill) the definition of Quantum Supremacy is
Quantum supremacy or quantum advantage is the potential ability of
quantum computing devices to solve problems…
P. C. Spaniel
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Quantum advantage with only Clifford gates (Gottesman Knill theorem)
Let's say I want to solve a computational task which input can be encoded in $n$ bits of information.
The look for a quantum advantage is (usually) asking to find a quantum algorithm in which there are exponentially fewer gates and qubits required…
Marco Fellous-Asiani
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How can one define contextuality within the circuit model?
It is in general believed that contextuality is one of the quantum resource that provides the quantum advantage. A context is usually defined in terms of a set of commuting observables. The quantum algorithms are usually describe employing the…
madeel
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Understanding Google's “Quantum supremacy using a programmable superconducting processor” (Part 1): choice of gate set
I was recently going through the paper titled "Quantum supremacy using a programmable superconducting processor" by NASA Ames Research Centre and the Google Quantum AI team (note that the paper was originally posted on the NASA NTRS but later…
Sanchayan Dutta
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What are the real advantages of superdense coding?
In superdense coding, two qubits are prepared by Eve in an entangled state; one of them is sent to Alice and the other is sent to Bob. Alice is the one who wants to send (to Bob) two classical bits of information. Depending on what pair of classical…
user72
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What is the advantage of quantum machine learning over traditional machine learning?
Why exactly is machine learning on quantum computers different than classical machine learning? Is there a specific difference that allows quantum machine learning to outperform classical machine learning?
Rob James
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