The composition rule for quantum systems is not the only possible one
- URL: http://arxiv.org/abs/2411.15964v1
- Date: Sun, 24 Nov 2024 19:31:13 GMT
- Title: The composition rule for quantum systems is not the only possible one
- Authors: Marco Erba, Paolo Perinotti,
- Abstract summary: We argue that the composition postulate deserves to be experimentally scrutinised independently of the other features of quantum theory.
We formulate a family of operational theories that are solely distinguished from quantum theory by their system-composition rule.
- Score: 0.0
- License:
- Abstract: Quantum theory provides a significant example of two intermingling hallmarks of science: the ability to consistently combine physical systems and study them compositely; and the power to extract predictions in the form of correlations. A striking consequence of this facet is the violation of $\textit{local realism}$, which has been experimentally demonstrated via so-called $\textit{Bell tests}$. The prediction of this phenomenon originates as quantum systems are prescribed to combine according to the $\textit{composition postulate}$, i.e. the tensor-product rule. This rule has also an operationally sound formulation -- rather than just a purely mathematical one -- given in terms of discriminability of states via local measurements. Yet, both the theoretical and the empirical status of such postulate has been constantly challenged over the decades: is it possible to deduce it from the remaining postulates? Here, we solve this long-standing problem by answering in the negative. We formulate a family of operational theories that are solely distinguished from quantum theory by their system-composition rule, while, at the same time, they cannot be told apart by Bell-like experiments. Quantum theory is thus established to genuinely embody more content than quantum correlations. As a result, foundational programs only based on single-system principles, or on bare correlations, are operationally incomplete. On the experimental side, ascertaining the independence of postulates is a fundamental step to adjudicate between quantum theory and alternative physical theories: hence, the composition postulate deserves to be experimentally scrutinised independently of the other features of quantum theory.
Related papers
- What is "quantum" about quantum gravity? [0.0]
We argue that if both the equivalence principle and quantum mechanics continue to survive experimental tests, that this favors epistemic'' interpretations of quantum mechanics.
arXiv Detail & Related papers (2024-05-13T21:19:50Z) - A computational test of quantum contextuality, and even simpler proofs of quantumness [43.25018099464869]
We show that an arbitrary contextuality game can be compiled into an operational "test of contextuality" involving a single quantum device.
Our work can be seen as using cryptography to enforce spatial separation within subsystems of a single quantum device.
arXiv Detail & Related papers (2024-05-10T19:30:23Z) - Quantum Theory Needs (And Probably Has) Real Reduction [0.0]
It appears that for quantum theory to be viable in a realist sense, it must possess genuine, physical non-unitarity.
Penrose's theory of gravitation-induced collapse and the Transactional Interpretation are discussed.
arXiv Detail & Related papers (2023-04-20T21:25:23Z) - Testing quantum theory by generalizing noncontextuality [0.0]
We prove that only Jordan-algebraic state spaces are exactly embeddable into quantum theory.
We propose an experimental test of quantum theory by probing single physical systems.
arXiv Detail & Related papers (2021-12-17T19:00:24Z) - Testing real quantum theory in an optical quantum network [1.6720048283946962]
We show that tests in the spirit of a Bell inequality can reveal quantum predictions in entanglement swapping scenarios.
We disproving real quantum theory as a universal physical theory.
arXiv Detail & Related papers (2021-11-30T05:09:36Z) - Quantum indistinguishability through exchangeable desirable gambles [69.62715388742298]
Two particles are identical if all their intrinsic properties, such as spin and charge, are the same.
Quantum mechanics is seen as a normative and algorithmic theory guiding an agent to assess her subjective beliefs represented as (coherent) sets of gambles.
We show how sets of exchangeable observables (gambles) may be updated after a measurement and discuss the issue of defining entanglement for indistinguishable particle systems.
arXiv Detail & Related papers (2021-05-10T13:11:59Z) - Quantum Causal Inference in the Presence of Hidden Common Causes: an
Entropic Approach [34.77250498401055]
We put forth a new theoretical framework for merging quantum information science and causal inference by exploiting entropic principles.
We apply our proposed framework to an experimentally relevant scenario of identifying message senders on quantum noisy links.
This approach can lay the foundations of identifying originators of malicious activity on future multi-node quantum networks.
arXiv Detail & Related papers (2021-04-24T22:45:50Z) - Observers of quantum systems cannot agree to disagree [55.41644538483948]
We ask whether agreement between observers can serve as a physical principle that must hold for any theory of the world.
We construct examples of (postquantum) no-signaling boxes where observers can agree to disagree.
arXiv Detail & Related papers (2021-02-17T19:00:04Z) - Operational Resource Theory of Imaginarity [48.7576911714538]
We show that quantum states are easier to create and manipulate if they only have real elements.
As an application, we show that imaginarity plays a crucial role for state discrimination.
arXiv Detail & Related papers (2020-07-29T14:03:38Z) - Conceptual variables, quantum theory, and statistical inference theory [0.0]
A different approach towards quantum theory is proposed in this paper.
The basis is to be conceptual variables, physical variables that may be accessible or inaccessible, i.e., it may be possible or impossible to assign numerical values to them.
arXiv Detail & Related papers (2020-05-15T08:08:55Z) - Quantum Mechanical description of Bell's experiment assumes Locality [91.3755431537592]
Bell's experiment description assumes the (Quantum Mechanics-language equivalent of the classical) condition of Locality.
This result is complementary to a recently published one demonstrating that non-Locality is necessary to describe said experiment.
It is concluded that, within the framework of Quantum Mechanics, there is absolutely no reason to believe in the existence of non-Local effects.
arXiv Detail & Related papers (2020-02-27T15:04:08Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.