2 corrected hyperfine structure description (again!).
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This is a great question. I won't claim to have the final answer, but I do think there is an important point to be made here.

Let's take the simple case of Rb87. There is a single electron in the valence shell, allowing the atomic structure to be described as "hydrogen-like." If you study the electronic structure, you find that the electron spin interacts with its own angular momentum about the nucleus. This gives rise to different possible orientations of angular momentum and spin with different energies. In other words, an energy splitting, known as fine structure. A further splitting of each of the fine structure lines results from the interaction of the electronicelectron's total angular momentum, and nuclear spinsspin. This is called hyperfine structure and it's roughly 3 orders of magnitude weaker than FS (but still quite important). So in the end, the possible states an atom can occupy are given by it's hyperfine energy levels, which in Rb87 are usually separated on the order of 100 MHz. THE reference for line data can be found here.

The point is that the atomic state is all we have. The coupling of electronic and nuclear states means that expressing the bare electron wavefunction becomes fruitless, much in the same way that you would never expect to describe an entangled photon using a single particle wavefunction.

An illuminating example comes from Cooper pairing, which gives rise to superconductivity. Cooper pairs are bosons, and so they can Bose condense. But the wavefunctions of the constituent electrons are now tied to their partners, making it impossible to give the state of just one of these paired electrons.

Just a thought, I hope it helps.

This is a great question. I won't claim to have the final answer, but I do think there is an important point to be made here.

Let's take the simple case of Rb87. There is a single electron in the valence shell, allowing the atomic structure to be described as "hydrogen-like." If you study the electronic structure, you find that the electron spin interacts with its own angular momentum about the nucleus. This gives rise to different possible orientations of angular momentum and spin with different energies. In other words, an energy splitting, known as fine structure. A further splitting of each of the fine structure lines results from the interaction of the electronic and nuclear spins. This is called hyperfine structure and it's roughly 3 orders of magnitude weaker than FS (but still quite important). So in the end, the possible states an atom can occupy are given by it's hyperfine energy levels, which in Rb87 are usually separated on the order of 100 MHz. THE reference for line data can be found here.

The point is that the atomic state is all we have. The coupling of electronic and nuclear states means that expressing the bare electron wavefunction becomes fruitless, much in the same way that you would never expect to describe an entangled photon using a single particle wavefunction.

An illuminating example comes from Cooper pairing, which gives rise to superconductivity. Cooper pairs are bosons, and so they can Bose condense. But the wavefunctions of the constituent electrons are now tied to their partners, making it impossible to give the state of just one of these paired electrons.

Just a thought, I hope it helps.

This is a great question. I won't claim to have the final answer, but I do think there is an important point to be made here.

Let's take the simple case of Rb87. There is a single electron in the valence shell, allowing the atomic structure to be described as "hydrogen-like." If you study the electronic structure, you find that the electron spin interacts with its own angular momentum about the nucleus. This gives rise to different possible orientations of angular momentum and spin with different energies. In other words, an energy splitting, known as fine structure. A further splitting of each of the fine structure lines results from the interaction of the electron's total angular momentum, and nuclear spin. This is called hyperfine structure and it's roughly 3 orders of magnitude weaker than FS (but still quite important). So in the end, the possible states an atom can occupy are given by it's hyperfine energy levels, which in Rb87 are usually separated on the order of 100 MHz. THE reference for line data can be found here.

The point is that the atomic state is all we have. The coupling of electronic and nuclear states means that expressing the bare electron wavefunction becomes fruitless, much in the same way that you would never expect to describe an entangled photon using a single particle wavefunction.

An illuminating example comes from Cooper pairing, which gives rise to superconductivity. Cooper pairs are bosons, and so they can Bose condense. But the wavefunctions of the constituent electrons are now tied to their partners, making it impossible to give the state of just one of these paired electrons.

Just a thought, I hope it helps.

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source | link

This is a great question. I won't claim to have the final answer, but I do think there is an important point to be made here.

Let's take the simple case of Rb87. There is a single electron in the valence shell, allowing the atomic structure to be described as "hydrogen-like." If you study the electronic structure, you find that the electron spin interacts with its own angular momentum about the nucleus. This gives rise to different possible orientations of angular momentum and spin with different energies. In other words, an energy splitting, known as fine structure. A further splitting of each of the fine structure lines results from the interaction of the electronic and nuclear spins. This is called hyperfine structure and it's roughly 3 orders of magnitude weaker than FS (but still quite important). So in the end, the possible states an atom can occupy are given by it's hyperfine energy levels, which in Rb87 are usually separated on the order of 100 MHz. THE reference for line data can be found here.

The point is that the atomic state is all we have. The coupling of electronic and nuclear states means that expressing the bare electron wavefunction becomes fruitless, much in the same way that you would never expect to describe an entangled photon using a single particle wavefunction.

An illuminating example comes from Cooper pairing, which gives rise to superconductivity. Cooper pairs are bosons, and so they can Bose condense. But the wavefunctions of the constituent electrons are now tied to their partners, making it impossible to give the state of just one of these paired electrons.

Just a thought, I hope it helps.