Ninety-seven years ago today, on August 30, 1928 (July 16, 1928), the Nobel Prize in Physics Wilhelm Wien died. Nobel Prize in Physics Wilhelm Wien Wilhelm Wien (WilhelmCarlWernerOttoFritzFranzWien, January 13, 1864 - August 30, 1928) was a German physicist who studied thermal radiation and electromagnetism. In 1911, he was awarded the Nobel Prize in Physics for his contributions to physical laws such as thermal radiation. Biography On January 13, 1864, Fischhausen was born in East Prussia (now Russia), a German physicist who studied thermal radiation and electromagnetism. His father, Carl Wien, was a landowner. 1879 in Rastenburg and 1880-1882 in Heidelberg. 1882, after graduating from high school, he studied mathematics at the University of Göttingen, and the same year he transferred to the University of Berlin. 1883-1885 worked in the laboratory of Hermann von Helmholtz. In 1886, he received his doctorate. His thesis was on the diffraction of light on metals and the effect of different materials on the color of refracted light. After that, due to the illness of his father, Wien had to go back to help manage his father's land. During this time he followed Helmholtz for a semester. In 1887, he completed experiments on the magnetic conductivity of metals to light and thermal radiation. In 1890, after the sale of his father's land, 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 received a university teaching qualification at the University of Berlin. In 1893, Wien discovered Wien's law of displacement through theoretical support in thermodynamics, spectroscopy, electromagnetism and optics, and applied it to academic theories such as blackbodies, uncovering new fields of quantum mechanics. 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 replace Olentgen and published the textbook "Hydrodynamik" in the same year. In 1902, he was invited to succeed Boltzmann as professor of physics at the University of Leipzig, but he declined the invitation. In 1906, he was invited to succeed Paul Drude as professor of physics at the University of Berlin, but he refused the invitation. In 1911, he was awarded the Nobel Prize in Physics for his contributions to physical laws such as thermal radiation. He traveled to Munich in late 1920, succeeding Röntgen again until his death in 1928. The Venn formula was awarded the 1911 Nobel Prize in Physics for the discovery of the law of thermal radiation - the Venn displacement law and the establishment of the Venn formula for blackbody radiation. At the end of the 19th century, people had realized that both thermal radiation and optical radiation are electromagnetic waves, and conducted in-depth theoretical and experimental research on the distribution of radiant energy in different frequency ranges, especially blackbody radiation. Wien and Ramel invented the first practical blackbody, the cavity emitter, which provided the required "complete radiation" for their experimental research. Wien proposed the displacement law of ideal blackbody radiation in 1893 on the basis of previous research: lmaxT = constant. The law states that as the temperature increases, the wavelength corresponding to the maximum of the radiant energy density shifts in the direction of short waves. Since the ratio of radiant flux density to radiant energy density is c/4, after measuring the lmax of the corresponding maximum value of radiant flux density, the temperature of the radiator can be determined according to Wien's displacement law. Optical thermometers are made according to this principle. Next, Wien studied the distribution of blackbody radiant energy by wavelength. Starting from thermodynamic theory, after analyzing the experimental data, he obtained a semi-empirical formula. That is, Wien's formula. Where El is the radiant energy per wavelength interval at wavelength l; C1 and C2 are two empirical parameters, determined by conforming to the experimental curve; T is the temperature at equilibrium. The Venn formula agrees well with the experiment in the short-wave band, but deviates significantly from the experiment in the long-wave band. Later, in the process of further exploring a better radiation formula, Planck established a quantum theory of radiation that is consistent with all experiments. However, when measuring temperature with an optical pyrometer, the Venn formula is still often used because it is simple and accurate enough. Venn diagram: Also called Venn diagram, it is used to show the diagram of the overlapping area of the set of elements. The history of Venn diagrams, in 1880, Venn (Venn) first used the form of fixed-position crossed rings and shading to represent logical problems in the paper "Graphical and Mechanized Representation of Propositions and Reasoning" (as shown in Figure 1). This representation method not only excited logicians - so much so that in the late 19th century, throughout the 20th century until today, many logicians have devoted themselves to this research. In a large number of logic works, Venn diagrams occupy a very important position, and Venn diagrams are also used in mathematics, especially in set theory.