Wolfgang Pauli - The great scientific face of the twentieth century

Wolfgang Pauli is one of the great scientific faces of the twentieth century. His contributions to atomic structure have a decisive role in establishing quantum theory.

Scientist Wolfgang Pauli
(Photo: pas-berlin)

By the time Wolfgang Pauli was born in Vienna, in 1900, the capital of the Austro-Hungarian empire was still the heart of the European intelligentsia: physicist Lugwig Bolzmann studied the instrument at Bruckner's house while Schonberg created the type. Twelve negative music, Freud introduced psychoanalysis and Wittgenstein brought the supreme language of philosophy to become popular.

As a natural science student, young Pauli quickly became a prodigy in physics and mathematics. The godfather of Ernst Mach and Pauli's father are both university professors who help him a lot in his studies. Mach, now a well-known man in the supersonic aerodynamics, criticized the foundations of physics that made him popular. Especially the concept of absolute space has a decisive influence on the theory of relativity (1905) and Einstein's general theory of relativity (1915).

After a series of critiques of relativity with 3 articles published in 1919 and an encyclopedia article up to 250 pages in 1921, the young Austrian man was greeted by Einstein himself. Even then he considered Pauli as ' The Successor ' (Wahl Sohn). The road in front of Pauli's eyes was open and in 1918, he attended the class of physicist Arnold Sommerfeld.

At this time Sommerfeld was working on the 'global model' of atoms discovered in 1910 with Ernest Rutherford's works: almost all mass concentrated in the nucleus, about 1 millionth in diameter of a part. billions of meters, around which very light charges are concentrated, like planets orbiting the sun. in 1913, Bohr demonstrated that one could explain the properties of emission or absorption of light by an atom by assuming borrowed particles , among the number of identifiable orbits. thanks to the ancient machines of the time, some static orbits were due to all the orbits specified by the name. It is said that electric orbits can be 'quantified' and need to have 3 numbers (in 3D space) to be able to describe them. While moving from this static orbit to another static orbit, the charge loses or absorbs energy in the form of light.

Experiments have shown that light absorbed or emitted is regulated when there is a magnetic field. To explain this result, Pauli calculated the vibrations affected by magnetic fields with each quantized orbit . In the winter of 1921-1922, he worked at Göttingen, then entered Two scientists: Wolfgang Pauli (standing) and Einstein (sitting) (Photo: scienceandsociety) ng 12/1924 in Copenhagen. It was a long journey through the desert in which the prodigy was not prepared. However, he observed the effect from while using two rules. According to the first rule , the static state of an electric particle is not defined by 3 but 4 numbers, with values ​​of -1/2 or +1/2. The second rule , known as the 'rule of exclusion' , clearly states that a condition can only be occupied by a single particle at the same time. Discovering this principle was awarded the Nobel Prize in physics in 1945.

Pauli said that, for the first rule, electric particles were available 'indifferent duality (Zweideutigkeit)' . So what is the direction of the 4th digit? Originating from a global image, Lars Kronig, Pauli's assistant in 1924, suggested that the electric particle orbits it as a spin and revolves around the central nucleus. Thanks to this quantitative assumption, the fourth figure was given, but Pauli stopped Kronig from announcing this.

Using analogy shows that the gyroscope actually turns only half. When turning 360 ^° , the electric particle state changes the mark. When needed, 720 ^o to return to the original position.

This image was so appealing that in 1925 Dutch scientists Geoge Uhlenberg and Samuel Goudsmit named the angular nature of this electric particle as spin. According to them, spin is consistent with the fourth quantum number. The name was retained, but in 1926, Kronig commented in Nature: 'It is assumed that the ghost was pushed down to the basement of the family house instead. because he took it out forever. '

The idea of ​​the gyro was condemned by Pauli right from the egg because the main reason was that he no longer believed and expressed the atomic processes. Ever since the formation of the rule, exclusion, he wrote to Niels Bohr and argued that quantum numbers for him seemed "much more realistic for orbits ." This observation was later used by Heisenberg and Göttingen's team to form quantum mechanics.

In the following years, in Zurich - where he moved from 1928, Pauli was involved in the development of new mechanics in which his use and expression made many physicists. confused . On the one hand, the close causality of a physical process (determinism) replaces static causality, in a single process.

Two scientists: Wolfgang Pauli (right) and Arnold Sommerfeld (left)
(Photo: scienceandsociety)

Poisoning is only described by probability words. On the other hand, descriptions can only be carried out by specific situations in which the process is observed. The method of physical assessment has achieved an experimental success but has also been rejected by a small number of physicists, including Einstein.

After becoming a German citizen, Pauli still had to leave Zurich for the United States in the years 1940-1945 for the reason that "his ancestors had 75% of Jewish blood ." There, while working on independent spin-theory theories, he thought about transforming the ground, in Heisenberg's way of calling, 'degrading the professional ethics of materialism' . emanating from Desmocrite's atomism and the mechanics of movement of matter points from Newton's point of view. Matter can be thought of as a collection of colliding particles as if it was a billard. Pauli went against the era of ontological formation, meaning that in the beginning of the seventeenth century, when Johannes Kepler found the laws of space mechanics.

Pauli discovered that Kepler's natural interpretation is often associated with 'prototypes' to be easily accepted. Especially from the idea that natural numbers are a prototype of the world, Kepler deduced that natural explanations must be quantified and this haunts him right from the first steps. As a result, a polemics happened between him and the alchemist Fludd, who insisted on a natural view that must be explained by qualitative. This is the 'big collision' between the mystical way of thinking alchemy and the thinking of natural scientists (which only appeared in the early seventeenth century). Recent studies have also reaffirmed the contradictory transition between these two ways of thinking.

Success in Kepler's steps and his successors directed physics to a more natural, mechanical concept. This concept is later added to the concept of observing physical processes: a principle phenomenon can be described without reference to human observation. But atomic physics has shown that describing a process cannot be referenced from any observations. Pauli's conclusion: 'In the seventeenth century, people have taken quite a long step' in the concept of mechanics.