Dear all: We have been a number of researchers to suppose that there is to kinds of spin, but the study of Dirac ’equation seems to give just one kind of spin. Indeed there are two kinds of solutions with the two subshells observed after the ns subshells and the correct number of magnetic states. The ns states belong to the second kind of solutions. The determination of the values of the magnetic quantum number m shows to have the following limits
For the first sub-shell -l -1 < m < l+2
and for the second -( l-2) < m < l+1
Then the angular momentum of all state is (m + ½).
This shows that there is always the same number of negative and positive values of the angular momentum, but the contribution proportional to ½h has always the same direction. This contribution is always positive and well verify from experimental results see “Total angular momentum and atomic magnetic moments”. This leads to suppose that there is just one own rotation or spin with respect to that of the proton.
Then this also leads to suppose that the spin is one component of interaction together with the linear one having equally the momentum ½h the both inducing the motion.
Dear Ed Greck: How do you explain the magnetic moment corresponding to the spin, but also a corresponding electric moment find by Dirac in his paper Proc. Roy. Soc. A117, p 610-624, 1928?
Agree with Ed, a spin interacts with another spin or a magnetic field.
The origin of spin is still a delicate topic, maybe an intrinsic effect, or
a relativistic effect.
Dear Ed and Juan: according to my approach of the physics, a motion need an interaction with something elf so the spin cannot be intrinsic “according to the Webster’s new world dictionary intrinsic: means not dependent on external circumstances”.
An intrinsic property, an electron has a spin as a tree has branches, or an electron also has charge.
Something you have to take as empirical data. It is measured in units of Planck constant; when you convert to magnetic moment, charge comes in to play also.
According to Dirac all the aspects of a quantum state are the result of the interactions introduce in his equation since we get all the observable properties. This means that there is no intrinsic property of the electron interacting with a nucleus.
Ed
Do you think that a Newton per Coulomb is the same unit as a weber per square meter?
Xavier
You seem to imply that spin arises due to its interaction with the nucleous.
As far as I know, this is not a conventional viewpoint . Both the proton and the
electron are both assumed to have charge and spin , before they are even allowed to interact.
Thus individual protons and electrons may be accelerated with a voltage, and spin detected as they pass through inhomogeneous magnetic fields.(That is empirical evidence)
The interaction is both Coulombic and spin spin (or magnetic moment magnetic moment), the later giving fine structure,
the former the quantum levels of the Hydrogen atom.
Regards, Juan
This might be an uneducated idea but... i am a thinker not a mathematician.
I believe an electron moves like a photon, as a sinus curve. How do a sinuscurve look in a 3D world? .... It is a spiral.
For two electrons to be able to meet and not kollide "to be at the same place at the same time" they have to be opposite, clockwise and counterclockwise with a starting position of 180 degrees against each other.
Maybe not relevant to this discussion, i don't know.
/Henrik
Dear all:
most of us do not really understand the Quantum State. I ask the question about the spin as a hypothesis, it is suppose with the attraction the other part of the interaction. In others words the interaction will always include the rotation together with the attraction.
In the case of the hydrogen atom there is no difficulty to suppose this.
If it is like this then the QM is easy to understand.
Regards, Xavier
Henrik
There is something to this. If two electrons are in the same quantum state, their spins have to be opposite.
It is called the exclusion principle. Thus you cannot have more than two electrons in a state with all other quantum numbers specified except spin. Including spin you may have only one. In heavier atoms than Hydrogen , you fill the levels with this restriction. Actually it would not help to be just a mathematician, you have to know some physics.
Regards, JW
Dear Juan,
If we keep in mind that the periodic table gives all the different quantum states, the equation of Dirac gives all the QS, this implies that there is no need to introduce the exclusion principle. Indeed the wrong hypothesis of spin up and down together with all the quantum states leads to the double number of QS.
Regards, Xavier
Xavier
Dont agree,
Even if you detect spin, it is still not obvious what it does in particle statistics.
The Dirac equation gives you spin automatically, whereas in Schrodinger you have to add it artificially.
Regards, JW
Dear Juan,
Excuse me, you are right, there is just one electron by quantum state but we do not need to specify the spin since there is just one.
Regards, Xavier
If we consider the approach of Bohr Sommerfeld, we use the classical mechanic of the planets there is no problem as long as we just consider the orbital motion. But this approach suppose that the attraction between the proton and the electron is just directional, as a result there is no linear component for the motion of the electron. If we consider a spherical interaction there is possibility to have a motion with two components for the momentum: one angular and another linear. This possibility leads to have the ½h quantum number for the both momentums.
The question is now: have we forgotten the linear momentum in the classical mechanic, in the quantum mechanics or not?
Nonsense, spin by itself has nothing to do with an interaction
Remember that its units are angular momentum, not energy.
It is just an interinsic angular momentum of an electron or other particle.
To understand the results in spectroscopy as the alkaline doublets, an angular momentum ½h the spin was initially supposed added or subtracted to the angular momentum of the electron around the proton. The solutions of the Dirac equation give a set of half-integer values of the angular momentum and the calculation of the magnetic momentum of different compounds from these values is in a very good agreement with the experiment: see “Total angular momentum and atomic magnetic moments”. Nothing indicate that the half-integer values must be the result of an additional momentum.
Spin 1/2, 3/2 and so on are the mark of a Fermion, like the electron, obeying the exclusion principle. Nucleons like the proton or neutron are also Fermions.
This is intrinsic angular momentum called spin, but there is also an orbital angular momentum. In some cases you add both to get total anular momentum
J=S+L
Not so simple a topic.
The notion of Fermion is based on a wrong hypothesis: the exclusion principle. If two electrons cannot occupy a same volume it is just because they have a volume two objects never occupy a same place: see Thermodynamic statistics and exchanges of energy or The Most Probable Distribution of the Thermal Energy
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