The principle of “quantum” that says why the atoms are the same

What makes the issue stable? Why are the atoms as they are? Why do different materials differ in their properties, such as electrical conductivity, density, fusion temperature, or spectrum of light absorption?

Such questions that physicists have practiced greatly in contracts that followed Dmitry Mandelv his periodic table of chemical elements in 1869. They received a new driving force around the beginning of the twentieth century with the discovery of JJ Thomson that the atoms were not retrieved, but they included the youngest, which are negative charged entities called electrons, the particles that determine them. After that, in 1911, Ernest Rutherford’s discovery that the atoms contained a central “nucleus” with a positive charge extensively packed.

This opened the door to an exciting discovery journey, to understand the rules that governs the offspring structures. I reached some forms of destination a century ago, at the beginning of 1925, with the principle of supporting our ideas about the stability of the article since then.

This is the principle of the exclusion of Pauli, which was named after the wonderful Austrian theoretical physicist who created it¹Wolfgang Pauli. It was a product of what was now classified as the ancient quantum theory – a period of the theory dedicated between 1900 and 1925 that led to the introduction of a consistent theory of quantum mechanics in 1925-1927 by Werner Heisenberg, Pascal Jordan, Max Bold, Irwin Schrobird, Paul Dirac. The principle of Pauli can be considered the height of the ancient quantum theory, unusually, survived to merge it into the new intention. The centenary is suitable to remember the physicist Odysseine in an attempt to understand the characteristics, amend and test the characteristics that the periodic table predicted, and how this principle led our understanding of the material – not just traditional things.

Bold hypotheses

The discovery of the infrastructure charged with atoms, which are generally neutral, created a great difficulty in the images of how the atoms work. In 1842, mathematician Samuel Irncho showed that there is no fixed and fixed distribution of such accusations, excluding the fixed models of the atom. However, despite the many attempts that follow the discovery of the without atomic structure, no one can reach a model of atomic stability and explain features such as the distinct and separate spectral lines from the light emitted from the atoms of different elements.

Shortly after Razerford’s discovery of the nucleus, the Danish physicist Niles Bohr began attacking this problem using the principles of quantum. He harnessed an idea presented by Max Planck in 1900 to explain the light group emitted from a non-reflective “black body”-that energy only comes in separate pieces, or quantity. Bohr applied to the light of the light emitted and absorbed by hydrogen atoms. The basic hydrogen atom is the simplest atom, now known to consist of one proton and one electron.

Bohr began with a picture in which the electrons revolve with the atomic nucleus, instead of planets revolve around a star. He assumed that there are specific values ​​of tropical energies in which electrons are not radiated, and therefore the atoms remain stable. Light and its absorption can only be emitted on the energy corresponding frequencies between two of these stable orbits, which were characterized by BOHR with different values ​​of the first “main” main number “”².

This bold hypothesis can explain some features of the hydrogen spectrum, but not all. Odyssey Bohr continued, as it included new spectral data and theoretical guesses. It was partially derived from classic mechanics, from the 1905 Albert Einstein matches for Atomic Electrons, and by providing more quantum ideas unlike classic physics. “QUANTUM OF Action” presented by Plankk (now known as Planck’s Stetter, HAnd that formed a “reduced” when divided into 2π, HIt is widely used), for example, indicates a lower amount of energy that the system can exchange. The principle of BOHR correspondence stated that when the main quantitative number is large, the predictions that were achieved using this mixed theoretical tools set must approach the known results of classic physics.

These efforts resulted in the introduction of two number of others³: The amount of the amount of the name, represents the volume of the angular momentum of the electron; The magnetic quantum number, which described the size of its magnetic moments. These additions were logical in the image of a flour to the atom: if the electron is moving along a circular orbit around the atomic nucleus, it will have an angular momentum; As a shaved body in a circular motion, you also expect to have a magnetic moment.

But again, this could not explain all the features of the hydrogen spectrum. By 1923-1924, the main puzzle was how to explain the effect of Ziman, as new spectral lines appear when the electrons that revolve around the external magnetic field react. This is the point where Pauli enters the story.

Electron exclusion

In early 1925, Pauli was only 24 years old. Indeed, a lecturer in theoretical physics at the University of Hamburg, Germany, was very appreciated by his peers. Since his youth in Vienna, it has been recognized as a miracle of mathematics – a cloak he did not wear easily, as is the case often. He asked for help through the new psychological analysis that psychologist Karl Young, who has maintained a permanent intellectual dialogue⁴. Pauli was a prolific correspondent, and his published messages are an important source of scientists and historians.

Pauli principle¹ He was informed of Edmund Clefton Stoner, but his approach was original – and unusual – in many senses. For a start, it appears to be mainly dependent on numbers, with no direct contact with well -known physics. Pauli’s main adding to the Bohr model was a fourth quantitative number-unlike Bohr, he had no analogy with classical physics, not even any visual representation in space. This new quantitative number, rotates, can only have two values, either +H/2 or –H/2. Electrons with the opposite values ​​of this quantitative number will interact differently with an external magnetic field, which leads to the division of spectral lines seen in the Zeman effect.

Nowadays, we know that the quantum number cannot be explained visually revolving: If you try to design an electron as a charged body on its axis, you will find that its surface will rotate more quickly than the light. This is the most powerful indicator of atomic models of the exotic quantum theory, full of features that challenge classic intuition.

Pauli did not put his exclusion principle on the basis of classic theories or dynamic principles, but he mentioned that it is a simple assumption: that no electronics can participate in the atom of the same group of four quantitative numbers. It is also distinguished by the historian John Hilbron, this statement was rather the Ten Biblical Commandments style: “It should be banned for more than one electron [in the same atom] … for the same values [all applicable] Quantum numbers “⁵. In this regard, Pauli Mechanica expected the new quantity, which – to the distress of many physicists, including the Schrogringer and Einstein – the intuitive visual models in building or interpreting the theory.