What Are Quantum Numbers?

A quantum number is a set of integers or semi-integers that describe the motion of electrons outside the nucleus in quantum mechanics. Because the change in the state of motion of the electrons outside the nucleus is not continuous, but quantized, the value of the quantum number is also not continuous, and can only take a set of integers or semi-integer numbers. There are four kinds of quantum numbers: the main quantum number n, the angular quantum number l, the magnetic quantum number m, and the spin quantum number s. The first three are derived during the mathematical analysis of the Schrodinger equation, and the last one is used to describe electron The spin motion was raised.

Quantum number representation

Some specific numbers that characterize the movement of microscopic particles.

Quantum number describes the value of each conservation number in the dynamics of a quantum system. They usually describe the energies of the electrons in an atom by nature, but they also describe other

Quantum number

Elementary particles contain many quantum numbers. Generally speaking, they are all particles. But it needs to be understood that elementary particles are the quantum states of the standard model in particle physics, so the relationship between the quantum numbers of these particles is the same as the Hamiltonian of the model, just like the Bohr atomic quantum number and its Hamiltonian. Relationship like that. That is, each quantum number represents a symmetry of the problem. This is more useful in field theory and is used to identify space-time and internal symmetry.

Generally, quantum numbers related to space-time symmetry include spin (related to rotational symmetry), parity, C-parity, and T-parity (related to Poincaré symmetry in space-time). The general internal symmetries include the number of lepton, baryon and charge. Entries have a more detailed list of these quantum numbers.

It is worth mentioning a minor but often confusing point. Most conserved quantum numbers are additive. Therefore, in a basic particle reaction, the sum of the quantum numbers before and after the reaction should be equal. However, some quantum numbers (commonly referred to as

Quantum number

(Parity) are multiplicative; that is, their product is conserved. Therefore, the multiplyable quantum numbers all belong to a kind of symmetry (like conservation), and the use of two symmetry transformations in this symmetry is the same as never used. They all belong to an abstract group called Z2.

In a weak magnetic field, the total number of quantum moments to increase the angular momentum magnetic quantum number m _j ; in a strong magnetic field, the LS coupling is released, and the quantum number to characterize its state is the main quantum number n, the angular quantum number l, and its magnetic quantum Number m _l and spin magnetic quantum number m _s ; for a multi-electron atom (LS case), the quantum number of a single electron is not a good quantum number, the quantum number characterizing the atomic state is the total orbital angular momentum quantum number L, the total spin angle Momentum quantum number S and total angular momentum quantum number J coupled by LS. In molecular physics, there are also vibrations and rotations inside the molecule. In addition to the quantum numbers that characterize the molecular state, there are also vibrational quantum numbers and rotational quantum numbers. In nuclear physics and particle physics, the states and properties of nuclear and subatomic particles are charged, angular momentum, parity, lepton number, baryon number, isospin and its third component, supercharge, G parity ,and many more. ^[4]