March 27, 1845 - Birth of Wilhem Conrad Röntgen, discoverer of X-rays


Wilhem Conrad Röntgen (sometimes spelled Roentgen) was born on March 27, 1845. He received the first Nobel Prize in Physics (1901) for the discovery of X-rays (also called Röntgen rays), which he made on November 8, 1895. As has already been made public, in the early years of the Nobel prizes there were many deserving candidates and the jury really had to decide the order in which they were to be awarded. The fact that the protagonist of our anniversary was the first indicates the value that his discovery had in his time, an importance that has increased in the intervening 120 years. Because there is no doubt that this has been a discovery in basic research with many and varied applications, from medicine, to security measures or study of the situation of materials; without forgetting the scientific applications, especially in the field of determining the structure of an infinity of substances of biological, chemical, physical or geological interest.

Although Röntgen was born in Germany, at the age of three he emigrated to the Netherlands (his mother was Dutch), studying there and entering the Technical University of Utrecht to study mechanical engineering; but he was expelled for some disciplinary matter that was never fully cleared up. After a brief stay at the University of Utrecht studying physics, he took the entrance exam at the Zürich Polytechnic (ETH) where he graduated as a mechanical engineer. During his stay at the ETH, he received classes in theoretical physics from Clausius and practical physics from Kundt, deciding to investigate physics and receiving a doctorate in this area in 1869.

Kundt was appointed assistant and accompanied him in his stages as a teacher in Würzburg and Strasbourg; him being appointed professor (lecturer) in this last university (1874). From this moment on, he began a journey through various universities and research centers, always improving professionally.

Thus, in 1875 he was appointed professor at the agricultural academy in Württemberg, and in 1876 he returned to Strasbourg as professor of physics where he stayed for three years, later moving to the University of Giessen as professor of physics. In 1888 he is appointed professor at the University of Würzburg, where he succeeded Kohlrausch.

Throughout his scientific career, Röntgen worked in numerous areas of experimental physics, such as thermodynamics (specific heat of gases), solid state (thermal conductivity in crystals, electrical properties and other characteristics of quartz), optics (influence of electromagnetic fields on polarized light, refractive indices of various fluids), fluids (influence of temperature on the compressibility of liquids, phenomena at the interface between two liquids). However, his pinnacle discovery (and one of the most important in the history of science) was that of X-rays.

At that time, numerous scientists were studying the effect of intense electric fields on gases in a high vacuum. Thanks to advances in technology (we must not forget that science and technology always feed off each other and the progress of one without the support of the other is unthinkable) adequate equipment was available to carry out reliable experiments. With these investigations cathode rays, canal (anodic) rays and X-rays were discovered. In fact, the generation of X-rays in experiments with discharges in vacuum tubes had been observed by other scientists before (for example, Lenard), but they did not realize the extent of their results. For this reason, it must always be taken into account that the person who discovers a phenomenon is the first scientist who is aware of the discovery.

Röntgen studied the phenomenon, he realized that it was a new type of radiation, that although he could not know if it was a wave or corpuscular phenomenon (today we know that it is both), he was aware that it was a new type of radiation with a power more penetrating than ultraviolet radiation and that was capable of passing through some solid objects (one of the first images is the accidental x-ray of his wife's hand, in which the bones and the ring are visible)

At first, the discovery of X-rays was met with skepticism by the scientific community, but the results were soon confirmed in other laboratories; and the numerous applications of this radiation began to be glimpsed and carried out; what has been the subject of scientific work for 120 years, but this is another story…

In 1900, Röntgen accepted the chair of physics at the University of Munich, where he founded the Institute for Physics at the University of Münich, taking charge of the experimental physics section (and Sommerfeld's of theoretical physics).

In Munich he remained for the rest of his life, dying on February 10, 1923.

Röntgen, without a doubt, a giant of science.

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