Virtual reality serves as a metaphor for understanding reality, due to surprising similarities in three key aspects:1.In virtual reality, an image of an object located in a particular location is created only upon observation.Similarly, in reality, probabilities for parameter values (such as the position of a particle) can be predicted, but they do not have a defined value prior to measurement.2. The parameter values of two entangled particles are determined instantly and definitively upon measuring one of them.This phenomenon occurs even when the particles are far apart in terms of spatial location.3. In virtual reality, it is not possible to measure or experience a unit smaller than a minimal value.Similarly, in reality, as with pixels in virtual reality, units smaller than a certain value cannot be measured or experienced.
Virtual reality serves as a metaphor for understanding reality, due to surprising similarities in three key aspects:1.In virtual reality, an image of an object located in a particular location is created only upon observation.Similarly, in reality, probabilities for parameter values (such as the position of a particle) can be predicted, but they do not have a defined value prior to measurement.2. The parameter values of two entangled particles are determined instantly and definitively upon measuring one of them.This phenomenon occurs even when the particles are far apart in terms of spatial location.3. In virtual reality, it is not possible to measure or experience a unit smaller than a minimal value.Similarly, in reality, as with pixels in virtual reality, units smaller than a certain value cannot be measured or experienced.
An experience may be described in terms of an accumulation of memory exemplars when it is unconscious. The conscious experience is the memory of one of these exemplars. Alternatively, an experience may be described in probabilistic terms when it is unconscious. According to this theory, memory simultaneously encompasses multiple memories—or none at all—and is represented in probabilistic terms. A conscious experience, however, corresponds to a single memory and is no longer described in probabilistic terms. The basis of this approach is a theory that explains reality in terms of a virtual reality model. Just as in virtual reality the parameters (of a perceived object) are determined only at the moment of observation or measurement, so too in actual reality, parameters are determined only at the moment of observation or measurement. Until that moment, the parameters can be described probabilistically. Similarly, just as in virtual reality there are minimal values for each parameter, in actual reality it is impossible to measure values smaller than a minimal threshold. And just as in virtual reality a change in one parameter may affect another parameter (belonging to a perceived object located elsewhere), so too in reality, a change in one parameter can influence another parameter perceived as spatially distant.
As children, many of us imagined our toys coming to life the moment we looked away, just like in Toy Story. Maybe they walked across the room and secretly planned adventures behind our backs. Surprisingly, physicists ask a very similar question about quantum particles: do they have definite properties before we measure them, or is reality decided at the moment of observation? Understanding the answer has led to technologies such as quantum computing, quantum teleportation, and quantum cryptography. In the quantum world, where particles such as electrons and positrons live, objects do not have definite positions or states but can exist in a superposition of possible states. Even stranger, two particles can become entangled, meaning measuring one, instantly predicts information about measuring the other, no matter how far apart they are. If our particles were Toy Story characters, Woody and Buzz, we could simply ask them questions in a courtroom trial and reveal the secret. In quantum mechanics, these questions are essentially measurements. However, Woody and Buzz can cheat in the trial, and so can our particles, by preplanning the outcome of any measurement in advance. This idea is known as a local hidden-variable theory, and for a long time, it was thought that there was no way to distinguish between such preplanned outcomes and outcomes determined only at the moment of measurement. In 1964, John Bell proposed a test, known as the Bell test, which can reveal this fact. This test can expose any hidden planned strategy. No matter how cleverly our particles coordinate, Bell’s test gives them no easy way to fake the results. His method is a statistical comparison between the results of measurements performed on a pair of particles, which consists of some inequalities that are satisfied if particles have pre-determined outcomes before they are separated, and violated for some of the quantum cases where particles live in a superposition of outcomes, and their outcomes are correlated to each other. But there is still a loophole. Remember the courtroom trial? Now imagine Woody and Buzz invoking the Fifth Amendment and refusing to answer questions. In physical terms, this means that the measurements are inefficient and detectors sometimes fail to produce a result. That missing information can mislead us if we perform our analysis based on the detected particles, a procedure known as post-selection, and this loophole is commonly referred to as the detection loophole. Many efforts have been made to close this loophole, both by increasing the detection efficiency of the detectors and by finding settings in which the minimum efficiency required for a reliable result is lower. In this thesis, we further investigated this loophole under the post-selection assumption. We considered a model in which the efficiency of each measurement depends on its outcome. We then studied how the Bell tests behave when the underlying theory of reality is either a local hidden-variable theory or a quantum-mechanical theory.
The concept of "reality" is often raised in the context of philosophical foundations of physics or interpretations of quantum mechanics. When this term is so raised, it is a warning to me that I am about to be led down a rabbit hole. Such diversions usually lead nowhere unless you consider endless discussions of Schrodinger's cat, wave function collapse, quantum non-locality, and parallel universes to be useful. A prime example is the famous Einstein, Podolsky, and Rosen paper wherein they concluded that the quantum wave function cannot provide a complete description of physical reality. In this essay I suggest that, in physics discourse, the term "reality" should be avoided at all costs.
Abstract: One of the most surprising consequences of quantum mechanics is the entanglement of two or more distant particles. In an entangled EPR two-particle system, the value of the momentum (position) for neither single subsystem is determined. However, if one of the subsystems is measured to have a certain momentum (position), the other subsystem is determined to have a unique corresponding value, despite the distance between them. This peculiar behavior of an entangled quantum system has surprisingly been observed experimentally in two-photon temporal and spatial correlation measurements, such as “ghost ” interference and “ghost ” imaging. This article addresses the fundamental concerns behind these experimental observations and to explore the nonclassical nature of two-photon superposition by emphasizing the physics of 2 ̸ = 1 + 1. 1
One of the most surprising consequences of quantum mechanics is the entanglement of two or more distant particles. In an entangled EPR two-particle system, the value of the momentum (position) for neither single subsystem is determined. However, if one of the subsystems is measured to have a certain momentum (position), the other subsystem is determined to have a unique corresponding value, despite the distance between them. This peculiar behavior of an entangled quantum system has surprisingly been observed experimentally in two-photon temporal and spatial correlation measurements, such as ghost interference and ghost imaging. This article addresses the fundamental concerns behind these experimental observations and to explore the nonclassical nature of two-photon superposition by emphasizing the physics of 2 is not 1 + 1.