Physical reality


  • Jesús Valdés-Hernández Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México
  • Javier Meza-Arroyo Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México
  • Jorge Luis Domínguez-Juárez Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México
  • Rafael Quintero-Torres Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México



Non-locality, non-contextuality, Bell's inequality, entangled states


The principle of non-locality, or the existence of systems of particles with properties that relate them even at great distances, are called entangled systems and defy the intuition that requires all relationships to be described by means of energy exchange or by material links, quantum physics presents non-locality as a consequence of objects being described by a single wave function and as such unless they decohere (losses its nonphysical link), the relationship remains, and each cannot be understood separately. Recently, there have been many technological models that can produce entangled systems. In addition to the examples that submicroscopic physics can illustrate, the simplest is spontaneous parametric fluorescence, which requires a laser and a parametric crystal that has allowed very elaborate experiments to be carried out and shows the relevance of quantum physics and the limitations of our perception. The examples described here have emerged over the years as attempts to make this concept more acceptable and try to guide the imagination to situations where these types of phenomena can be plausible and point to human perception with the duality of bringing us closer to the appreciation of nature, but at the same time, it is the main limitation to appreciate and understand nature. The relevance of this concept was recognized with the Nobel Prize 2022 in physics, and it can be summarized as the Proof of the Bell inequality using anecdotes from a Nobel non-recipient.


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How to Cite

J. Valdés-Hernández, J. Meza-Arroyo, J. L. Domínguez-Juárez, and R. Quintero-Torres, “Physical reality”, Rev. Mex. Fis. E, vol. 21, no. 2 Jul-Dec, pp. 020210 1–, Jul. 2024.