Solve the Cube: Calculating Electron Energy in a Nucleus

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This was one of the bonus questions on my homework. Teacher says whoever gets it right, consider yourself a god or goddess. Can anyone help me solve this?

Calculate the lowest possible energy for an electron confined in a cube of sides equal to 10pm, and a cube of sides equal to 1fm. The latter cube is about the size of a nucleus. What do your energies say about the chance of an electron being inside the nucleus? *Hint: Assuming that the uncertainty in the position of the electron is the length of a side of a cube, find the change in Energy (triangle E is symbol) for each cube.
 
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From the appearance of \Delta E I assume you have been given the uncertainty principles for energy and time and for momentum and length. To use the E,t one, you have to get a \Delta t out of the box side length, and I suggest you allow your electron to have a maximum speed of c, so the time it would spend in crossing the box would be ...? And the \Delta E for that \Delta t would be...?
 


Calculating the energy of an electron in a nucleus is a complex problem and requires knowledge of quantum mechanics. However, we can use some basic principles to approach this problem.

Firstly, we need to understand that an electron in a nucleus is confined within a very small space and thus, its position is uncertain. This is where the hint given by the teacher comes in handy. By considering the uncertainty in the position of the electron to be the length of a side of a cube, we can use the Heisenberg uncertainty principle to calculate the uncertainty in the momentum of the electron.

Next, we can use the Schrödinger equation to calculate the energy of the electron in each cube. The Schrödinger equation is a mathematical representation of the behavior of quantum particles, including electrons. By solving this equation for each cube, we can obtain the lowest possible energy for the electron in each case.

The change in energy, symbolized by ΔE, can then be calculated by taking the difference between the energies of the two cubes. This value will give us an idea of the energy difference between an electron in a larger cube (10pm) and a smaller cube (1fm) that represents the size of a nucleus.

The resulting energies will tell us about the likelihood of an electron being inside the nucleus. Generally, the lower the energy, the higher the probability of finding the electron in that region. Therefore, the lower energy of the electron in the smaller cube (1fm) suggests a higher chance of the electron being inside the nucleus.

In conclusion, solving this bonus question requires knowledge of quantum mechanics and the use of mathematical equations. It is a challenging problem, but if solved correctly, it can give us valuable insights into the behavior of electrons in a confined space like a nucleus. Good luck with your calculations!
 
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
If we release an electron around a positively charged sphere, the initial state of electron is a linear combination of Hydrogen-like states. According to quantum mechanics, evolution of time would not change this initial state because the potential is time independent. However, classically we expect the electron to collide with the sphere. So, it seems that the quantum and classics predict different behaviours!
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