Biography of Alexandre-Edmodn Becquerel (1822-1891)

French physicist, born in Paris in 1822 and died his hometown in may 1891. Member of one of the most illustrious scientific dynasties of Europe, became interested in the study of light and made notable contributions to the knowledge of the photoelectric effect and spectroscopic characteristics of sunlight. It also investigated successfully the phenomenon of phosphorescence, the magnetic and ParaMagnetic properties of the substances, and the phenomena of electrochemical decomposition. His achievements include a proposal for modification of the famous Faraday's law, which could offer a satisfactory explanation to certain cases that seemed to be an exception.

Was the son of the very famous physical and chemical Antoine Cesar Becquerel (1788-1878), considered the founder of electrochemistry; and the father of one of the great geniuses of the universal science, Antoine-Henri Becquerel (1852-1908), recipient of the Nobel Prize in Physics in 1903, which has gone down in history of science as the discoverer of the natural radioactivity.

In addition, was grandfather of two other great scientists, both sons of Antoine-Henri Nobel Prize: Jean (1878-1953), who was also a brilliant physicist and made great contributions to crystallography studies; and Paul Becquerel (1879-1955), who excelled as a biologist, studied the effects of low temperatures on living beings and contributed to invalidate the theory of the radiopanspermia, by demonstrating the impossibility that germs travel through space under the impulse of light from the star radiation (since, if so, it would be destroyed by ultraviolet radiation(, low temperatures and vacuum almost absolute).

He inherited from his father a strong passion for scientific knowledge, which allowed him to conclude with utmost brilliance his high school studies at the Ecole Polytechnique (Polytechnic School) in Paris at the age of sixteen.

Aware that his future employment was in teaching, the young Alexandre-Edmond joined then in the Ecole Normale (Normal School) in Paris, where he earned a degree of master which allowed him to teach classes in some schools as prestigious as the Agronomy Institute of Versailles (which joined as a teacher in 1849) and the Conservatory of Arts and crafts in Paris (in which teaching staff figured since 1853). Finally, ended his long and fruitful dedication to teaching to occupy the square of Professor of physics at the Muséum d'Histoire Naturelle (Natural History Museum) in Paris, in which succeeded his father as soon as this had died.

Since long ago, Alexandre-Edmond had been working closely with his father a numerous research papers. He became interested, as a discipline first by electrochemistry, founded by his father; and, in their research on the phenomena of electrochemical decomposition, it found a new formulation of the Faraday's law (which States that, in an electrolytic process, the amount of chemical change that occurs depends on the electric charge applied, as well as mass and involved ion load). With its new formulation, Alexandre-Edmond Becquerel could explain some cases which, until then, were being considered as exceptions that escaped to the provisions of this law.

Then you go in the study of light, with special attention to the photoelectric phenomenon (consisting of the emission of electrons by a material that has been irradiated with a beam of light). Father and son, passionate study of luminance (or property that they possess some bodies emit light unless a temperature rise occurs in them), analysed in depth these bodies subjected to irradiation of a light bulb and established the following conclusions: If, after the removal of the light source, the luminescence disappears, are facing a fluorescent body; but, in the cases in which luminescence persists after removal the source which sheds the light on them, we should talk about phosphorescent bodies. After this distinction, Antoine Becquerel and his son Alexandre could technically define the phenomenon of phosphorescence as "property that have some substances emit light in the dark after having been exposed to a light source".

In addition, Alexandre-Edmond Becquerel deeply into the study of spectroscopic characteristics of solar light and electric light (i.e. in those properties of these two types of light that have to do with the emission or absorption of radiation by matter). All your comments on this matter were collected in one of the most important works of the scientific literature of the 19th century, light, their causes and effects, posted by the second saga Becquerel, in two volumes, in 1867 and 1868.

His scientific research also encompass the field of magnetic properties (i.e., those that are related to the way in which the magnetic force fields affect different materials and substances) and ParaMagnetic (which are those magnetic properties than caused by rotation or spin of the electron, whose measure turns out to be very valuable, since it provides information on the chemical bonds).

Member of the Académie des Sciences (Academy of Sciences) from the 18 May 1863, Alexandre-Edmond Becquerel died in Paris in the spring of 1891, thirteen years after the demise of its longtime parent. By that time, his son Antoine-Henri, called to become one of the great glories of universal physics, was also a prestigious scientist and a distinguished member of the Academy of Sciences.