Edouard Branly French inventor, physicist and professor. Date of Birth: 23.10.1844 Country: France

Biography of Édouard Branly

Édouard Branly was a French inventor, physicist, and professor. He is less well-known compared to figures like Marconi, Popov, and Lodge, but his invention, the Branly coherer, played a crucial role in the development of wireless telegraphy.

Born in Amiens, France, Branly received his education at the prestigious École normale supérieure, graduating in 1868. He earned his doctorate in science in 1873 and a doctorate in medicine in 1882. From 1875 to 1897, he held a position as a physics professor, and from 1897 to 1916, he served as a professor of medicine.

Branly's most notable invention, the coherer, was developed in 1890. He built upon the discoveries made by the Italian physicist Temistocle Calzecchi-Onesti in 1884, who demonstrated that metal filings in an insulating tube with two connected electrodes could conduct electricity under the influence of an external signal. Further research revealed that the filings, which typically had high resistance, would lose their resistance when subjected to physical agitation. This effect was explained by a thin layer of oxide covering the filings, which was disrupted by the proper strength of the signal, making the entire structure more conductive. The Branly coherer proved to be highly useful for detecting radio waves, and it is also credited with the term "radio." Oliver Lodge, Alexander Popov, and Guglielmo Marconi later incorporated the coherer into their own radio receivers.

Branly demonstrated his first model of the "radiowire" or "radio-conductor" in 1890, with the term "coherer" being proposed by Oliver Lodge in 1893. Lodge was able to build a functioning receiver based on the coherer by adding a "decoherer" to provide the necessary agitation. Later, Marconi continued and further developed Lodge's work.

In 1907, the coherer was replaced by crystal detectors. Despite his significant contributions, Branly was nominated for the Nobel Prize three times but never received it. In 1911, he was elected to the French Academy of Sciences, competing against Marie Curie. Both scientists achieved remarkable results in their respective fields and faced opposition within the Academy. Curie faced prejudice due to her gender, while Branly was criticized for being a devout Catholic who had left the Sorbonne for the Catholic University of Paris. Ultimately, Branly emerged as the victor by a margin of two votes.

In 1936, Branly was admitted to the Pontifical Academy of Sciences. It was Branly who inspired Marconi to send his best wishes over the English Channel during the first radio conversations. Marconi acknowledged Branly as one of the key contributors to the development of wireless telegraphy. Branly's work was recognized in 2010 when it was included in the list of key discoveries in electrical and computer engineering by the IEEE.