Joseph John Thomson Biography

Joseph John Thomson (December 18, 1856 – August 30, 1940) was born in Cheetham, Manchester, UK. British physicist and mathematician, awarded the Nobel Prize in Physics in 1906, for his contributions to the conduction of electricity through gases.

Thomson is recognized for his studies on the electron and the Plum Pudding Theory, also called Thomson’s atomic model, this theory delves into the atomic structure of the atom and the importance of electrons or negative charge. Son of Joseph James Thomson and Emma Swindells, he had as a brother Frederick Vernon Thomson. His father was a bookseller, who was always concerned about providing the best education for his children. He wanted Joseph J. Thomson to study engineering.

Education and career

From an early age, he was interested in mathematics and knowledge; and so in 1870, he entered Owens College, around 1876 he attended Trinity College, Cambridge. He obtained his degree as a Bachelor of Mathematics in 1883. After finishing his studies he began to work as a teacher at the same institution, where he taught mathematics and physics. In 1884, he was in charge of the Cavendish chair, and later, he was appointed Director of the Cavendish Laboratory at the University of Cambridge, a position he held from 1918 until he died in 1940.

While working at the Cavendish Laboratory he met physicist Niels Bohr, with whom he had a close relationship. At this point, he was a professor of the famous New Zealand physicist and chemist  Ernest Rutherford. In 1890, he married Sir George E. Pagetm’s daughter, Rose Elisabeth.

Thomson served as professor of natural philosophy at the Royal Institution of Great Britain located in Great Britain. He held this position between 1905 and 1918. Upon leaving the institution, the position was taken by Thomas Young. At the same time, he was President of the Royal Society between 1915 and 1920. After being the chair at the Royal Institution of Great Britain, he returned to the Cavendish Laboratory of the University of Cambridge. Thomson passed away on August 30, 1940, in Cambridge. He was later buried in Westminster Abbey.

Thomson’s discoveries and works

Thomson began researching atomic structure while studying and teaching at the Cavendish Chair.

Throughout his career he investigated cathode rays; While he was conducting various experiments with these, he discovered that electric fields could deflect the direction of cathode rays. After this discovery, he devoted himself entirely to investigating the cause of the deviation, the way it deviated, and their relationship to the charge and mass of the particles. In 1897 while conducting experiments with cathode-ray tubes, he discovered a new particle, which was lighter than hydrogen, this was called an electron. Thomson was the first scientist to identify subatomic particles.

After discovering the electron he focused on unraveling all the mysteries that surrounded this subatomic particle, for this he built a tool that would allow the analysis of the composition of the atom, this instrument was patented with the name of Mass Spectrometer. With this tool, Thomson found the relationship between the mass of the electron and the electric charge. Using this tool, he discovered that neon has two isotopes, which are neon-20 and neon-22.

Thomson’s Atomic Model

After several years of research, Thomson formulated the Plum Pudding Theory, also known as Thomson’s Atomic Model. This was a new model of atomic structure in which Thomson stated that electrons were like plums in a pudding made of positive matter. His model was wrong since it assumed that the electrons were mixed homogeneously with the positive charges, later it was shown that it was not that way.

After finishing his studies on the electron, he focused on electrical conduction; he carried out various experiments and studies on the passage of electricity through the interior of gases. In it, he studied, analyzed, and calculated what was the amount of electricity transferred by each atom, also, he calculated the number of molecules per cubic centimeter. This work earned him the Nobel Prize in Physics in 1906. Throughout his career as a physicist, he published numerous studies, among the most prominent are: The discharge of electricity through gases (1898), Conduction of Electricity Through Gases (1903), The Corpuscular Theory of Matter (1907), and The Electron in Chemistry (1923) and Recollections and Reflections (1936).