Questions tagged [contextuality]

For questions related to contextuality (a foundational concept in quantum mechanics) as relevant to quantum computing and/or quantum information. Contextuality means that in any theory that attempts to explain quantum mechanics deterministically, the measurement result of a quantum observable depends on the specific experimental setup being used to measure that observable, in particular, the commuting observables being measured with it. (Wikipedia)

Filter by
Sorted by
Tagged with
8
votes
1answer
74 views

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 ...
2
votes
0answers
52 views

Can the Peres-Mermin square be reframed as a statement on the associated conditional outcome probabilities?

As mentioned in this answer, and links therein (assuming I'm understanding correctly), (non)contextuality can be defined as a property of a given set of conditional probability distributions, that is, ...
2
votes
1answer
139 views

How does quantum contextuality relate to mutually commuting observables?

I am trying to get a better understanding of what is the idea behind quantum contextuality. Quoting from the wikipedia page (emphasis mine): Quantum contextuality is a foundational concept in ...
4
votes
1answer
870 views

What does negative probability represent?

"Negative energies and probabilities should not be considered as nonsense. They are well-defined concepts mathematically, like a negative of money." -Paul Dirac The abstract from Photon-phonon-photon ...
15
votes
2answers
1k views

Is it true to say that one qubit in an entangled state can instantaneously affect all others?

When a qubit is measured, there is a ‘collapse of the wave-function’ as a result is randomly chosen. If the qubit is entangled with others, this collapse will also effect them. And the way it affects ...
8
votes
2answers
172 views

Are there any experimental groups currently measuring quantum contextuality?

I work as a theorist with my current research interests in "quantum contextuality". For those perusing the question, this is essentially a generalization of non-locality where we can show a quantum ...