Hardy's Paradox: Exploring Copenhagen & Bohm's Theories

[Descartz2000]

Can someone explain how Hardy's Paradox is resolved? As well, what could someone infer from this regarding both Copenhagen Interpretation and Bohm's theory?

 

[Demystifier]

Hardy's paradox is resolved by realizing that measurement CHANGES the properties of the system. In the Copenhagen interpretation the measurement creates the properties (which before the measurement do not even exist), while in Bohm's theory the properties are changed by instantaneous influences between distant particles.

For more details, see e.g. Secs 5.5 and 5.6 in
http://xxx.lanl.gov/abs/quant-ph/0609163 [Found.Phys.37:1563-1611,2007]

 

[Entropia]

Hardy's Paradox is a thought experiment that challenges the principles of quantum mechanics, specifically the Copenhagen Interpretation and Bohm's theory. In this paradox, two particles are entangled and then separated. According to the Copenhagen Interpretation, the act of measurement causes the particles to collapse into definite states, while Bohm's theory suggests that the particles have definite states even before measurement. However, Hardy's Paradox proposes a scenario where the particles' states are dependent on each other, leading to a contradiction between the two theories.

To resolve this paradox, it is important to understand that both the Copenhagen Interpretation and Bohm's theory are just interpretations of quantum mechanics, and may not fully capture the complexity of the quantum world. In reality, the behavior of particles may not be fully explained by either interpretation.

One possible resolution to Hardy's Paradox is through the concept of non-locality, where the entangled particles are connected in a way that allows them to influence each other's states instantaneously, regardless of distance. This would mean that the particles do not have definite states until they are measured, and the act of measurement on one particle affects the state of the other particle.

In terms of what this could infer about the Copenhagen Interpretation and Bohm's theory, it suggests that both interpretations may have limitations in fully explaining the behavior of quantum particles. The paradox highlights the need for a more comprehensive understanding of quantum mechanics. It also raises questions about the nature of reality and the role of observation in shaping it. Ultimately, Hardy's Paradox serves as a reminder that our current theories and interpretations may continue to be challenged and evolve as we delve deeper into the mysteries of the quantum world.

 

[Entropia]

Hardy's Paradox, also known as the Hardy's thought experiment, is a famous paradox in quantum mechanics that challenges our understanding of the Copenhagen Interpretation and Bohm's theory. It was first proposed by Lucien Hardy in 1992 and has since been a topic of debate among scientists.

In this paradox, two particles, A and B, are entangled and sent towards two separate detectors, X and Y. The detectors are set up in a way that if A is detected at X, then B will not be detected at Y, and vice versa. However, according to the Copenhagen Interpretation, the particles do not have definite properties until they are measured. This means that both A and B can exist in a superposition of states, being both detected and not detected at the same time.

On the other hand, Bohm's theory suggests that the particles have definite properties even before they are measured. This means that the outcome of the experiment is predetermined and the particles are simply revealing their pre-existing properties.

So, how is Hardy's Paradox resolved? The answer lies in the concept of counterfactual definiteness. This means that even though the particles may not be measured, they still have definite properties. In other words, the particles have a predetermined outcome, even if it is not observed.

This resolution has implications for both the Copenhagen Interpretation and Bohm's theory. For the Copenhagen Interpretation, it suggests that the particles do have definite properties and the act of measurement simply reveals these properties. This challenges the idea of superposition and the role of the observer in determining the outcome of an experiment.

For Bohm's theory, the resolution of Hardy's Paradox supports the idea of pre-existing properties and challenges the concept of non-locality. Non-locality is the idea that entangled particles can influence each other's properties instantaneously, regardless of the distance between them. However, the resolution of Hardy's Paradox suggests that the particles' properties were predetermined and not influenced by each other.

In conclusion, Hardy's Paradox raises important questions about our understanding of quantum mechanics and the role of measurement in determining the properties of particles. The resolution of this paradox has implications for both the Copenhagen Interpretation and Bohm's theory, challenging some of their fundamental principles.