How Do Particle Measurements and Dynamic Equations Impact Quantum Mechanics?

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The discussion centers on two key questions regarding particle measurements and their implications in quantum mechanics. First, it explains that according to the collapse postulate for separable 2-particle systems, a measurement on one particle does not affect the other, as their states are independent and not entangled. Second, it addresses the measurement problem arising from the linearity of the dynamical equations, specifically the Schrödinger equation, which complicates understanding when and how wave function collapse occurs. This issue highlights the probabilistic nature of quantum measurements and the ambiguity surrounding what constitutes a measurement. The conversation emphasizes the importance of personal effort in grasping these complex concepts.
swoosh18
I would be so thankful for anyone who could help me with any of the following questions (this is for a class entitled Physics and Philosophy):

1) Show explicitly (by means of the collapse postulate for 2-particle systems) that if the state of a certain pair of particles is separable, then a measurement on either one of them can have no effect whatsoever on the physical reality of the other.

2) Explain how the linearity of the dynamical equations of motion lead to the measurement problem. What assumptions go into your argument?


(these questions are in reference to David Albert's book: Quantum Mechanics and Experience
 
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1) You probably should post these in the "homework" section.

2) No one will do your homework for you. Show us what you understand of the problem, what you have done so far, and, as precisely as possible, where you run into trouble. That will help people understand what kind of hints will help you the most. The more work YOU do, the better.
 
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Sure, I would be happy to help you with your homework. However, it is important for you to understand the concepts and solve the problems on your own. I can offer guidance and clarification, but it is ultimately up to you to do the work and learn from it. With that being said, let's take a look at the questions you have.

1) The collapse postulate for 2-particle systems states that when a measurement is made on one particle, the state of the other particle will collapse into a corresponding state. This means that if the state of a pair of particles is separable, then the state of one particle is independent of the state of the other particle. This also means that any measurement on one particle will not affect the physical reality of the other particle because their states are not entangled. Therefore, the collapse postulate for 2-particle systems shows that measurements on one particle cannot have any effect on the physical reality of the other particle.

2) The measurement problem in quantum mechanics arises from the linearity of the dynamical equations of motion. This means that the Schrodinger equation, which governs the evolution of a quantum system, is linear and does not allow for the collapse of the wave function upon measurement. This leads to the question of how and when the wave function collapses, and what causes it to collapse. This is known as the measurement problem.

The assumption that goes into this argument is that the measurement process should have a definite and unambiguous outcome. However, in quantum mechanics, the measurement process is probabilistic and the outcome is not definite until the measurement is made. This leads to the question of what constitutes a measurement and how it affects the system being measured. David Albert's book, Quantum Mechanics and Experience, delves deeper into this topic and discusses different interpretations of quantum mechanics that attempt to address the measurement problem.

I hope this helps you in understanding and tackling these questions. Remember, it is important to put in the effort and try to solve the problems on your own. Good luck!
 
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