CDP: Non Classical Correlations at Spacelike Separation

In summary, the conversation discusses the Cluster Decomposition Principle (CDP) and its relation to the non-classical correlations observed in EPR experiments without action at a distance. The CDP, defined as S α1α2β1β2 = S α1β1Sα2β2, is connected to the locality assumption (P(A,B|a,b,λ) = P (A|a,λ)P(B|b,λ)) and the Extended Causality described by @A. Neumaier. The CDP may account for the non-classical correlations with non-separability, as separability is an assumption in EPR experiments. However, further approximations and assumptions are required to connect the
  • #1
morrobay
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Does the Cluster Decomposition Principle explain the spacelike non classical correlations in EPR experiments
without action at a distance ? With CDP defined : S α1α2β1β2 = S α1β12β2
Does this definition equate to the locality assumption : P(A,B|a,b,λ) = P (A|a,λ)P(B|b,λ)
If so then does the CDP equate to the Extended Causality described by @A. Neumaier and account for the non classical correlations with non separability, in part since separability is an EPR assumption ?
 
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  • #2
The Cluster Decomposition Principle in itself explains nothing. It is a property of observed asymptotic states and a result in relativistic quantum field theory; see Weinberg's Vol 1.

To derive extended causality one needs assumptions about relativistic causality. These are embodied classically in covariant actions leading to hyperbolic PDEs, and in QFT in the spacelike (anti)commutativity of causal fields.

To get from interacting fields individual particles (as used in EPR experiments) one needs to make approximations, since particles give a meaningful description only asymptotically (as scattering states), and hence only when they are approximately free for a sufficiently long time. Since extended causality is a property of solutions of classical PDEs, one should expect it to remain valid in the quantum case. But at present this is a conjecture only.
 
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Related to CDP: Non Classical Correlations at Spacelike Separation

1. What is CDP and what does it stand for?

CDP stands for "Correlations at Spacelike Separation" and it refers to a type of quantum correlation that exists between two distant particles that are separated in space.

2. How is CDP different from classical correlations?

CDP is different from classical correlations because it is a type of quantum correlation that cannot be explained by classical physics. It involves particles that are entangled, meaning they are connected in a way that is not possible in classical physics.

3. What is the significance of studying CDP?

Studying CDP is significant because it helps us to better understand the mysterious world of quantum mechanics. It also has potential applications in quantum communication and computing, as well as shedding light on the fundamental nature of reality.

4. How are CDPs measured?

CDPs are typically measured using quantum tomography techniques, which involve manipulating and measuring the state of the particles involved in the correlation. This allows us to determine the strength and nature of the correlation between the particles.

5. What are the implications of non-classical correlations at spacelike separation?

The existence of non-classical correlations at spacelike separation challenges our understanding of space and time, and may have implications for our understanding of causality and the fundamental laws of physics. It also has potential applications in secure communication and quantum information processing.

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