Number of Particles in Left Half of a Confined Box with Varying Energies

AI Thread Summary
The discussion revolves around calculating the number of particles in the left half of a one-dimensional box containing 1000 neutral spinless particles with varying energy levels. The participants note that the energies correspond to specific quantum states, but the probabilistic nature of particle distribution complicates the calculation. It is emphasized that measuring the number of particles in the left half yields a probabilistic result rather than a fixed number. The original poster seeks guidance on how to approach the problem given these complexities. The conversation highlights the challenges of applying quantum mechanics principles to this scenario.
phoenix95
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Homework Statement


1000 neutral spinless particles are confined in a one-dimensional box of length 100 nm. At a given instant of time, if 100 of these particles have energy 4ε0 and the remaining 900 have energy 225ε0, then the number of particles in the left half of the box will be approximately

(a) 441

(b) 100

(c) 500

(d) 625

Homework Equations

The Attempt at a Solution


Energies 4ε0 and 225ε0 correspond to E2 and E15 respectively, so I tried finding the expectation value for a single particle at these energy levels which turns out to be L/2 for both. But then I thought it is irrelevant for the problem, because I can't assign a single wave function to each of the particle and carry out the calculations.
Can anyone please help me?

Thanks
 
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I think this is a misguided problem. The left side of the box is not in a particular number state, which means if you measure the number of particles of the left half of the box, the result would be probabilistic.
 
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Xu Shuang said:
I think this is a misguided problem. The left side of the box is not in a particular number state, which means if you measure the number of particles of the left half of the box, the result would be probabilistic.
In that case, how should I start?:smile:
 
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