Is the Dimensionality of Vector Spaces the Same for Different Quantum States?

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SUMMARY

The dimensionality of vector spaces for different quantum states is not the same, as demonstrated in the particle in a box problem. The energy eigenbasis is countably infinite, while the position eigenbasis is uncountably infinite. This discrepancy arises because the eigenstates of the position operator (X) exist in a larger topological vector space compared to the eigenstates of the Hamiltonian operator (H). Consequently, the spectral equations for X and H do not yield solutions within the same vector space.

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arpon
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Consider the particle in a box problem. The number of energy eigenbasis is 'countable' infinity. But the number of position eigenbasis is 'uncountable' infinity. x can take any value from the interval [0,L] Whichever basis I choose, shouldn't the dimensionality of the vector space be the same?
 
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That is true, iff the „eigenstates” are element of the same topological vector space. But the space of the eigenvectors of X is larger than the space of the eigenvectors of H, or, equivalently, the two spectral equations for X and H do not have solutions in the same space.
 
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