January 13, 1864 - Wilhelm Wien was born, a German physicist and Nobel laureate in physics. (died 1928)

Wilhelm Carl Werner Otto Fritz Franz Wien (January 13, 1864 - August 30, 1928) was a German physicist who studied thermal radiation and electromagnetism. In 1893, Wien discovered Wien's displacement law, supported by theories such as thermodynamics, spectroscopy, electromagnetism, and optics, and applied it to academic theories such as blackbodies, uncovering new fields of quantum mechanics. In 1911, he was awarded the Nobel Prize in Physics for his contributions to physical laws such as thermal radiation.

Wien was born on January 13, 1864 in Fischhausen, East Prussia (present-day Russia). His father Carl Wien was a landowner. He studied secondary school in Rastenburg in 1879 and Heidelberg from 1880 to 1882. After graduating from high school, he studied mathematics at the University of Göttingen in 1882 and transferred to the University of Berlin in the same year. He worked in the laboratory of Hermann von Helmholtz from 1883 to 1885, and received his doctorate in 1886. His thesis topic was the diffraction of light on metals and the effect of different materials on the color of refracted light. Afterwards, due to Wayne's father's illness, Wayne had to go back to help manage his father's land. During this period, he followed Helmholtz for one semester, and in 1887 completed experiments on the magnetic permeability of metals to light and heat radiation.

It was not until 1890, after the sale of his father's land, that Wien returned to Helmholtz and worked as his assistant at the National Institute of Physics and Engineering, doing research on industrial topics. In 1892 he was admitted to the University of Berlin as a university professor. In 1896 he went to the RWTH Aachen University as a professor of physics to succeed Philip Leonard. In 1899 he became a professor of physics at the University of Giessen. In 1900 he went to the University of Würzburg to succeed Lentgen. The same year he published the textbook Hydrodynamik. In 1902 he was invited to succeed Boltzmann as a professor of physics at the University of Leipzig, and in 1906 he was invited to succeed Paul Drude as a professor of physics at the University of Berlin, but he declined both invitations. At the end of 1920, he went to Munich and succeeded Roentgen again until his death in 1928.

He married Luise Mehler in 1898 and had four children. William Wien's cousin, Max Wien, was a pioneer in high-frequency electronics.

At the National Institute of Physical Engineering, Wien worked with Ludwig Holborn to study methods for measuring high temperatures with Le Chatelier thermometers, while conducting theoretical research on thermodynamics, especially the laws of thermal radiation. In 1893, Wien proposed the law that wavelength changes with temperature, which was later called Wien's displacement law.

In 1894, he published a paper on the temperature and entropy of radiation, extending the concepts of temperature and entropy to radiation in a vacuum. In this paper, he defined an ideal object capable of completely absorbing all radiation and called it a black body. In 1896, he published Wien's formula, Wien's Law of Radiation, which gave this relationship to determine blackbody radiation and provided a new method to describe and measure high temperatures. Although it was later proven that Wien's formula only worked for short waves, Wien's research enabled Planck to use quantum physics methods to solve radiation problems in thermal balance. Wien also won the 1911 Nobel Prize in Physics for this research.

After traveling to Aachen in 1896 to succeed Philip Leonard, he established a laboratory there to study electrostatic discharge in a vacuum. In 1897, he began to study cathode rays. With the help of a high vacuum tube with a Leonard window, he confirmed Jean-Baptiste Piran's discovery two years earlier that cathode rays consisted of negatively charged particles (electrons) moving at high speeds. Almost at the same time as Joseph Thomson's discovery of electrons in Cambridge, Wien measured the relationship between the charge and mass of these particles in a different way than Thomson, and came up with the same result as Thomson, that is, their mass was only one thousandth that of a hydrogen atom.

In 1898, Wien studied the anodic rays discovered by Eugen Goldstein and pointed out that their positively charged amount was equal to the negatively charged amount of cathode rays. He measured their offset under the influence of magnetic and electric fields, and concluded that the anodic rays were composed of positively charged particles and that they were not heavier than electrons. The method used by Wien led to mass spectrometry about 20 years later, allowing accurate measurements of the masses of various atoms and their isotopes, as well as calculations of the energy released by nuclear reactions. In 1900, Wien published a theoretical paper on the electromagnetism foundations of mechanics, and then continued to study anodic rays. In 1912, he discovered that in an environment that was not high vacuum and when the gas pressure was not very weak, anodic rays passed through and collided with atoms of residual gases, losing and recovering their charge during motion. In 1918, he again published the results of his research on anodic rays. He measured the cumulative decrease in luminosity after the ray left the cathode. Through these experiments, he inferred that what is called a decline in atomic luminosity in classical physics corresponds to the limited time that atoms are active in quantum physics.

Wien's work contributed to the transition from Newtonian classical physics to quantum physics, and as Max von Laue (1914 Nobel Prize in Physics) put it, Wien's monumental glory is that "he led us to the very gates of quantum physics."

Comments: One of the pioneers of quantum mechanics in the world and a respectable physicist.