I Can anyone explain me this quantum entanglement experiment

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The discussion centers on a quantum entanglement experiment and questions its underlying mechanisms, including the roles of energy conservation and interference. Concerns are raised about the credibility of the referenced article from SCIRP, noted for publishing questionable research. An explanation of passive quantum entanglement state tomography is provided, highlighting the free evolution of entangled particles and subsequent correlation measurements. The thread concludes with a suggestion to seek more reliable, peer-reviewed sources for further exploration of quantum entanglement. The conversation emphasizes the importance of credible research in understanding complex quantum phenomena.
James2018
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Entanglement Generation in Spatially Separated Systems Using Quantum Walk
Experiment

I have encountered this experiment that generates quantum entanglement but I cannot understand its mechanism. Is the conservation of energy and momentum involved? Is interference part of this experiment? What are the phenomena that contribute together to generate entanglement in this experiment? What degree of freedom is part of the entangled state?

https://www.scirp.org/html/1-1300041_20127.htm
 
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That article was published in the Journal of Quantum Information SCience which is published by SCIRP. SCIRP was on Beall's list of predatory publishers (https://web.archive.org/web/20170103170850/https://scholarlyoa.com/publishers/) and is generally known to publish articles of questionable quality.

To be honest, I would not bother with trying to understand this article as the chances that the article is incorrect are extremely high. If you are interested in entanglement generation in quantum walks in general, it might help to have a look at the initial works on that, e.g.: https://iopscience.iop.org/article/10.1088/1367-2630/7/1/156
 
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Likes dextercioby, gentzen, PeroK and 3 others
Here is how a passive quantum entanglement experiment based on quantum state tomography would work:

In this technique, the system is left to evolve freely, without any external intervention or measurement. This is in contrast to active entanglement quantum state tomography, where measurements are performed on the system during its evolution. This is done by measuring the correlations between the particles after they have evolved for a certain period of time.

Here is an example of an experiment that could be used for passive entanglement quantum state tomography:

  1. Prepare a pair of entangled particles, such as two photons, using a source of entangled pairs
  2. Allow the pair to evolve freely for a certain period of time.
  3. Measure the correlations between the photons. This can be done by measuring the polarization of each photon using polarizing filters
  4. Repeat steps 2 and 3 for different evolution times.
  5. Use the measured correlations to reconstruct the quantum state of the system. This can be done using techniques such as maximum likelihood estimation or Bayesian inference.
  6. Verify the reconstructed state by comparing it to the expected state based on the properties of the entangled pair source.
 
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Thread closed for Moderation...
 
This thread will remain closed. A new thread on this topic, based on a more reliable and peer-reviewed reference would be welcome.
 
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