Born December 18, 1856, Cheetham near Manchester, UK
Died August 30, 1940, Cambridge, UK
Nobel Prize in Physics 1906.
The wording of the Nobel Committee: “In recognition of the enormous contribution to theoretical and experimental studies of the conductivity of gases.”

Our current character seems extraordinary even compared to the “ordinary” Nobel laureate. Well, let's start with the fact that seven of his “scientific sons” also became Nobel laureates (he lived to receive five prizes). Like many of his “scientific grandchildren” (we wrote about both the most famous “scientific son” and one of his grandchildren). His own son also became a Nobel laureate, and for the same elementary particle that our hero discovered. Did you guess it? Well, of course... Meet JJ.

And this is not the pseudonym of some rapper, this is good old England. "JJ" is a proper name, although it is short for "Sir Joseph John Thomson". However, Thomson was not a nobleman by birth, like his most famous student Rutherford. He was born into a bookseller family, also JJ (Joseph James) Thomson and Emma Swindales. The father wanted his son to receive a good education and became an engineer, and therefore at the age of 14 JJ Jr. went to Owens College, now known as the University of Manchester.

Two years later, Thomson Sr. passed away. There was no money either, but my mother and her good academic performance, which provided her with a scholarship, helped. The training continued. Owens College had an excellent experimental physics course. However, to study physics, even then you needed a good knowledge of mathematics. And Thomson enters Trinity College, Cambridge, where he studies theoretical physics and mathematics. In 1880, at the age of 24, he received his bachelor's degree and began working at the Cavendish Laboratory (in fact, the Cambridge Physics Department).

modern look Cavendish Laboratory
Let us remind readers that the laboratory got its name not from the name of the famous chemist Henry Cavendish, but from the name of the Chancellor of Cambridge, William Cavendish (Henry was the 2nd Lord Cavendish, and William the 7th), who donated a lot of money for its construction. Although, of course , the memory of Henry Cavendish was preserved in it.

Four years later, in 1884, when Thomson had not yet turned 28, and had no special scientific achievements other than the fame of a good physicist and mathematician with “ with the right hands", he was not registered, something amazing happens. The director of the Cavendish Laboratory, John William Strett, the third Baron Rayleigh, a seasoned man who later (in 1904) would receive the Nobel Prize for the discovery of argon and leave his title in the history of science in terms of Rayleigh scattering and Rayleigh waves, resigned. Before Strett, the post of director was held by James Clerk Maxwell himself (by the way, who spent a lot of time analyzing and publishing the scientific archive of Henry Cavendish).

John William Strett

And then Thomson is appointed to this important post. Marvelous! They write that one American physicist who was interning in a laboratory, having learned about the new Cavendish professor, fled to his homeland with the words “it’s pointless to work under a professor who is only two years older than you,” and one Cambridge teacher-mentor spoke more harshly: “... critical times are coming at the university when just boys become professors!” In this case, the choice was made by the retiring Strett himself. Perhaps because in the absence of, as they say, “breakthrough” results so far, Thomson’s talent was still obvious? No wonder his first printed scientific work published in the “Proceedings of the Royal Society of London” when he was only 19. In any case, Strett was not mistaken - Thomson excellently led the laboratory for more than a third of a century, just as his predecessor received the Nobel Prize and handed over his post to an equally great scientist... But about that Later.

Having become director and given greater freedom of action, Thomson began to study the electrical conductivity of gases in a Crookes tube. This is a glass vessel with two electrodes at opposite ends, from which almost all the air has been pumped out. Actually, William Crookes, the creator of this device, discovered that when the air is sufficiently rarefied, the glass at the end of the tube opposite the cathode begins to fluoresce with yellow-green light, apparently under the influence of some kind of radiation, which was called cathode rays.

Fluorescence in the cathode tube

Sir William Crookes with cathode tube. Cartoon 1902

A few words must, of course, be said about William Crookes himself, the creator of the cathode tube. The famous scientist who discovered thallium and obtained helium in the laboratory was an avid spiritualist. In 1874, at the age of 42, in the prime of his scientific powers, he published an article in which he stated that spiritualism is scientific and that spirit phenomena actually occur. The scandal was such that Crookes had to “lay low” for many years - wait for his scientific authority to become unshakable, as well as his position in the Royal Scientific Society, wait for a knighthood (1897) and in 1898 make a kind of “coming out” ", but in the spirit of those years.

Crookes and the spirit he summons

Crooks stated that he was a committed homosexual spiritualist. This is what Crooks remained until his death in 1919. So from 1913 to 1915, the Royal Society of London was headed, in our opinion, by a pseudoscientist (but only that). By the way, in 1915, Crookes was replaced in this post by our hero for 6 years.

But let's go back three decades, from old Crookes to young Thomson. By the beginning of his studies with the Crookes tube in scientific world there were serious disputes - relatively speaking, representatives British school(and Crookes himself) believed that cathode rays are a stream of certain particles, and representatives, relatively speaking, of the German, based on the not very reliable experiments of Hertz, believed that they were waves of the ether - a certain substance that permeates space.

Thomson cathode tube c magnetic coils to deflect electrons

Thomson’s main merit was that he was able to show: cathode rays are still particles (corpuscles, as Thomson himself called them), and at the same time they are always the same. Thomson even managed to measure the ratio of charge to mass of a particle - now one of the fundamental constants. This is how electrons were discovered, and humanity took the first step into the depths of the atom. Thomson himself became the author of the first model of the structure of the atom, which was called “raisin pudding” - in some smeared positively charged body, “raisins” - electrons - float or are simply interspersed.

Thomson atom

Half a century later, his own son and student would receive the Nobel Prize for being able to show the dual nature of the electron by discovering its wave properties. And much earlier, his first student would take the next step in understanding the structure of the atom and destroy Thomson’s “tasty” model.

Even before the discovery of the electron (1896−1897), in 1895, another important event occurred in the life of Thomson and all of British and world science (no, not the Nobel Prize - it was not awarded at all then, and Thomson would receive his well-deserved award only in 1906; as we understand, in the first years the Nobel committee “selected” worthy physicists from a very large pool). Thomson's first doctoral student (research-student), a young New Zealander named Ernest Rutherford, appeared at the Cavendish Laboratory.

New Zealand scientific journal "Rutherford"

It was with him that Thomson made the main discovery of his life. Rutherford's letters to his bride preserved for us a description of Thomson and his family. “He is very pleasant in conversation and is not at all an old-fashioned fossil. In terms of appearance, he is of average height, dark-haired and very youthful. Very badly shaved and wears rather long hair. He has a thin, oblong face, an expressive head, two deep vertical folds going down from his nose... He invited me to lunch at his place on Scroop Terrace, where I saw his wife - a tall brown-haired woman with a sickly face, but very friendly and talkative...”

I must say that Ji-Gi was a completely decent man and a normal lab manager. Once you have your eye on a student in your own lab, get married. Moreover, the student’s father is a Regius Professor of Medicine at Cambridge. In 1890, 28-year-old Thomson and Rose Paget got married, and two years later their first child, George Paget, was born. Nobel laureate in 1937 for the discovery of the wave nature of the electron, if that.

George Paget Thomson

By the way, if anyone wants statistics on nominations, here you go:

Nobel Prize in Physics, 1906. 18 nominations.

J.J. Thomson - 8 nominations
Gabriel Lipmann (1908 laureate) - 3
Henri Poincaré (he was nominated 51 times, but was never given the prize) - 3
Ludwig Boltzmann (who deserved the prize, but alas, died in 1906) - 2
The rest - 1 each (among them Thomson's namesake - William Thomson (1824-1907), better known as Lord Kelvin, who also did not manage to receive the prize)

Thomson lived a long life. He earned his nobility, as Vladimir Voroshilov liked to say, “with his own mind,” he became a Nobelist. In 1913, he became head of the Royal Society of London, and in 1919 he transferred the professorship to Rutherford, who returned to Cambridge. Seven of his collaborators became Nobel laureates, starting with the first doctoral student Rutherford, whom Thomson outlived and buried. He waited until his son won the Nobel Prize. He was the head of the Royal Society of London, the head of Trinity College...

He was 84 years old when he died; The Second was in progress World War The Battle of Britain was in full swing. JJ received the highest honor of being buried in Westminster Abbey. By the way, another interesting point: Thomson is one of the few Nobelists of the early years whom we can see and hear. On the Nobel Committee website there is a post made in 1934, where Thomson talks about the discovery of the electron.

And about the very contribution of Thomson, who began to create the Cavendish Laboratory school, one can say in the words of Oliver Lodge: “How much less would the world know if the Cavendish Laboratory had not existed in the world. But how much would the fame of this illustrious laboratory have diminished if Sir J. J. Thomson had not been one of its directors!

Cavendish Research Group. 1932. Seated (from left to right): Ratcliffe, P. Kapitsa, D. Chadwick, Ladenberg, J. J. Thomson. E. Rutherford, C. Wilson, F. Aston, C. Ellis, P. Blackett D. Cockcroft. Second row: fourth from left - Marcus Oliphant; fourth from right - Norman Feather.

In 1897, British physicist Joseph John Thomson (1856-1940) made the discovery of the electron after a series of experiments aimed at studying the nature of electrical discharge in a vacuum. The famous scientist interpreted the deflections of the rays of electrically charged plates and magnets as evidence that electrons were much smaller than atoms.

The great physicist and scientist had to become an engineer

Thomson Joseph John, the great and mentor, should have become an engineer, so his father believed, but at that time the family did not have the means to pay for education. Instead, young Thomson attended college at Machester and later Cambridge. In 1884 he was appointed to the prestigious position of Professor of Experimental Physics at Cambridge, although he personally carried out very little experimental work. He discovered a talent for developing equipment and diagnosing related problems. Thomson Joseph John was a good teacher, inspired his students and devoted considerable attention to the broad problem of developing the science of teaching in the university and secondary schools.

Nobel Prize Laureate

Thomson received many different awards, including the Nobel Prize in Physics in 1906. He also had the great pleasure of seeing some of his close associates receive their Nobel Prizes, including Rutherford in chemistry in 1908. A number of scientists, such as William Prout and Norman Lockyer, have suggested that atoms are not the most tiny particles in the Universe and that they are built from more fundamental units.

Discovery of the electron (briefly)

In 1897, Thompson proposed that one of the basic units was 1000 times smaller than an atom, this became known as the electron. The scientist discovered this through his research on the properties of cathode rays. He estimated the mass of the cathode rays by measuring the heat generated when the thermal transition rays hit and compared it with the magnetic deflection of the ray. His experiments show not only that cathode rays are 1000 times lighter than a hydrogen atom, but also that their mass was the same regardless of the type of atom. The scientist came to the conclusion that the rays consist of very light, negatively charged particles that are universal building material for atoms. He called these particles "corpuscles", but later scientists preferred the name "electrons", proposed by George Johnston Stoney in 1891.

Thompson's experiments

By comparing the deflection of cathode ray beams with electric and magnetic fields, the physicist obtained more reliable measurements of the charge and mass of the electron. Thomson's experiment was carried out inside special cathode ray tubes. In 1904, he hypothesized that the atomic model represented a sphere of positive matter in which the positions of particles were determined by electrostatic forces. To explain the generally neutral charge of the atom, Thompson suggested that the corpuscles were distributed in a uniform field of positive charge. The discovery of the electron made it possible to believe that the atom could be divided into even smaller parts, and was the first step towards creating a detailed model of the atom.

History of discovery

Joseph John Thomson is widely recognized as the discoverer of the electron. The professor spent most of his career working on various aspects of the conduction of electricity through gases. In 1897 (the year the electron was discovered), he experimentally proved that so-called cathode rays were actually negatively charged particles in motion.

Many interesting questions are directly related to the discovery process. It is clear that the characterization of cathode rays had been studied even before Thomson, and several scientists had already made important contributions. Is it then possible to say with certainty that it was Thomson who was the first to discover the electron? After all, he did not invent the vacuum tube or the presence of cathode rays. The discovery of an electron is a purely cumulative process. The credited pioneer makes a major contribution by generalizing and systematizing all the experience accumulated before him.

Thomson cathode ray tubes

The great discovery of the electron was made using special equipment and under certain conditions. Thomson conducted a series of experiments using an elaborate cathode ray tube, which included two plates with rays traveling between them. The long-standing controversy regarding the nature of the cathode rays produced when an electric current passes through a vessel from which most of the air has been evacuated has been suspended.

This vessel was a cathode ray tube. Using an improved vacuum method, Thomson was able to make a convincing argument that these rays were composed of particles, regardless of the type of gas or type of metal used as a conductor. Thomson can rightly be called the man who split the atom.

Scientific recluse? This is not about Thomson

The outstanding physicist of his time was by no means a scientific recluse, as is often thought of brilliant scientists. He was the administrative head of the highly successful Cavendish Laboratory. It was there that the scientist met Rose Elizabeth Paget, whom he married in 1890.

Thomson not only managed a number of research projects, he also financed the renovation of laboratory facilities with little support from the university and colleges. He was a talented teacher. The people he gathered around him from 1895 to 1914 came from all directions of the world. Some of them received seven Nobel Prizes under his leadership.

It was while working with Thomson at the Cavendish Laboratory in 1910 that he carried out research that led to the modern understanding of internal

Thomson took his teaching work very seriously: he regularly lectured to primary classes in the morning and taught science to graduate students in the afternoon. The scientist considered the doctrine useful for the researcher because it requires periodic revision of basic ideas and at the same time leaving room for the possibility of discovering something new that no one had paid attention to before. The history of the discovery of the electron clearly confirms this. Thompson devoted most of his scientific work to the study of the passage of electrically charged current particles through vacuum space. He studied cathode and x-rays and made enormous contributions to the study of atomic physics. In addition, Thomson also developed a theory of the motion of electrons in magnetic and electric fields.

, Nobel Prize Laureate

Joseph John Thomson(1856-1940) - English physicist, founder scientific school, member (1884) and president (1915-1920) of the Royal Society of London, foreign corresponding member of the St. Petersburg Academy of Sciences (1913) and foreign honorary member (1925) of the USSR Academy of Sciences. Director of the Cavendish Laboratory (1884-1919). Investigated the passage of electric current through rarefied gases. Discovered (1897) the electron and determined (1898) its charge. Proposed (1903) one of the first models of the atom. Author of studies of electric currents in rarefied gases and cathode rays, who explained the continuity of the spectrum of X-rays, put forward the idea of ​​the existence of isotopes and received experimental confirmation of it. One of the creators of the electronic theory of metals. Nobel Prize (1906).

Joseph Thomson was born on December 18, 1856, Chatham Hill, a suburb of Manchester. Died August 30, 1940, in Cambridge; buried in Westminster Abbey.

A mathematician comes to physics

Joseph Thomson was born into the family of a bookseller. His father wanted him to become an engineer, and when Joseph reached the age of fourteen, he was sent to study at Owen College (later the University of Manchester).

A civilized society is like a child who received too many toys for his birthday.

Thomson Joseph John

Until the mid-19th century, there were no research laboratories at universities, and professors who conducted experiments did so at home. The first physical laboratory was opened in Cambridge in 1874. It was headed by James Clerk Maxwell, and after his early death - by Lord Rayleigh, who retired in 1884. And then, unexpectedly for many, Thomson, a twenty-eight-year-old mathematician who had just begun experimental research, was elected Cavendish professor and laboratory director. The future showed that this choice turned out to be very successful.

Beginning of Joseph Thomson's experiments

The attention of many physicists at that time was attracted by the problems of electricity and magnetism. Maxwell's equations have already appeared (although they have not yet entered into general use). However, Thomson turned not to that part of electrodynamics that considers the field strengths generated by “given” sources (i.e., the densities of charges and currents of which are known), but rather to the question of the physical nature of these sources themselves. In Maxwell's own theory this issue was hardly discussed. For him electricity- everything that generates a magnetic field (distributions of electric charges that do not change over time create only electric fields).

Thomson was fascinated by the question of charge carriers. He began by studying currents in rarefied gases, which was then being done in a number of other laboratories. Thomson discovered that the conductivity of gases increases under the influence of X-rays. He obtained important results while studying cathode rays. those. flows emanating from the cathodes (negative electrodes) of the discharge tubes. Various opinions were then expressed about their physical nature. Most German physicists believed that these were waves similar to X-rays, while the English saw them as a stream of particles.

In 1894, Thomson managed to measure their speed, which turned out to be 2000 times less than light, which was a convincing argument in favor of the corpuscular hypothesis. A year later, French experimenter Jean Perrin figured out the sign electric charge cathode rays: falling on metal cylinder, they charged it negatively. It remained to determine the mass of the particles. Thomson was also able to solve this problem brilliantly. But before starting the experiment, he turned to theory and calculated how a charged particle should move in crossed electric and magnetic fields. The deflection of such a particle was found to depend on the ratio of its charge to mass.

The experiment began (it should be noted that Joseph Thomson most often, having carefully thought out the experiment in all details, left it to his assistants). His results showed that the mass of the particles is almost 2000 times less. than the lightest ions - hydrogen ions. As for the charge, for ions it has already been reliably calculated on the basis of electrolysis experiments and turned out to be positive. Since the hydrogen atom has zero charge, this suggested that there were equal and opposite carriers of discrete portions of electric charges. Those particles that were part of the cathode rays were soon called electrons. Their discovery was one of most important achievements physics of the late 19th century, and it is directly related to the name of Thomson, who was awarded for it in 1906 Nobel Prize.

Atom model

In the same 1897, when the discovery of the electron was registered, D. Thomson turned to the problem of the atom. Having become convinced that, contrary to its name, the atom is not indivisible, Thomson proposed a model of its structure. According to this model, the atom acted as a positively charged “drop,” inside which small negatively charged balls—electrons—“floated.” Under the influence of Coulomb forces, they were located near the center of the atom in the form of chains of certain configurations (in which one could even see something reminiscent of order in the periodic table of Mendeleev). If some push deflected electrons from equilibrium positions, oscillations began (connection with spectra!) and Coulomb forces sought to restore the original equilibrium. Although experiments subsequently carried out in the same Cavendish laboratory by Thomson's successor, Ernest Rutherford, forced the abandonment of this model, it played a significant role in the formation of ideas about the structure of matter.

From electrons to nuclei

Beginning his work at the Cavendish Laboratory with the study of X-ray scattering, Joseph Thomson came up with the formula that bears his name and describes the scattering of electromagnetic waves by free electrons. This formula still plays a prominent role in particle physics.

Thomson's role in the discovery of the photoelectric effect and thermionic emission was also important. The idea of ​​using crossed fields to measure the ratio of particle charges to their masses also turned out to be very fruitful. This idea is the basis for the work of mass spectrographs, which found wide application in nuclear physics and, in particular, played a significant role in the discovery of isotopes (nuclei with different masses but identical charges, which determines their chemical indistinguishability). Note that the prediction of the existence of isotopes and the experimental detection of some of them was also made by Thomson.

Joseph Thomson was one of the brightest classical physicists. True, he saw the emergence of quantum theory (the formation of which took place to a large extent before his eyes and with the direct participation of his young colleagues), the emergence of the theory of relativity and atomic and nuclear physics. Moreover, his personal participation in that grandiose revision of the entire physical worldview that the first decades of the new century brought was undoubted and profound. But until the end of his days he retained faith in the existence of a mechanical ether, despite the successes of the relativistic theory, which he perceived only as a reflection of some mathematical properties of Maxwell’s equations. In relation to quantum theory, he remained a skeptical observer for quite a long time and changed his opinion about it only after his son George Paget Thomson experimentally discovered the wave properties of electrons (for which he was awarded the Nobel Prize in 1937).

100 famous scientists Sklyarenko Valentina Markovna

THOMSON JOSEPH JOHN (1856 - 1940)

THOMSON JOSEPH JOHN

(1856 – 1940)

The famous English physicist Joseph John Thomson was born on December 18, 1856 in Cheetham Hill, a suburb of Manchester (England) in the family of Joseph James Thomson and Emma Thomson, née Swindells. His father was a famous bookseller and publisher.

Joseph John and his brother Frederick Vernon, who was two years younger than him, spent their summer holidays with their mother.

In 1870, when Joseph John was 14 years old, his father sent the boy to study at Owens College (later the University of Manchester), where he was to major in engineering. Two years later, his father died, but thanks to a scholarship and financial support from his mother, young Thomson continued his studies at Owens College.

College teachers, Osborne Reynolds and Balfour Stewart, instilled in the capable student an interest in physics. Unlike many other colleges in Great Britain, Owens College offered a course in experimental physics, which Thomson really liked.

At the age of 16, Joseph John won a prize in mathematics, and the following year was awarded a prize in engineering.

After graduating from Owens College in 1876 with the title of engineer, Thomson, on the recommendation of his teachers, entered Trinity College, Cambridge University, one of the most prestigious colleges in the country. Here he studied mathematics and its applications in the field of theoretical physics. After some time, Thomson became a fellow at the University of Cambridge, and later he was awarded a personal scholarship.

In 1880, according to the results of the Cambridge examination in mathematics, Thomson became the second Wrangler (the first was the famous Joseph Larmore). Joseph John was awarded the Smith Prize for his outstanding academic performance. In the same year, the young scientist received a bachelor's degree in mathematics and entered the Academic Council Trinity College. From this time until the end of his life Thomson was the soul and driving force of the college. For two years he worked there 18 hours a week. In 1883, Joseph John became a lecturer and later (in 1918) master (head) of the college.

In 1871, the first physics research laboratory was opened at the University of Cambridge. Until this time, universities did not have their own research laboratories, and scientists in most cases worked and made discoveries at home. The first director of the laboratory was the great James Clerk Maxwell, who initiated its discovery. After his early death, another great physicist, Lord Rayleigh, was elected director.

Many great discoveries were made in the laboratory; it later received the name Cavendish Laboratory (after Henry Cavendish) and became the world center of experimental physics.

In 1884, the famous John William Strett, Lord Rayleigh (also a future Nobel laureate), resigned, deciding to continue Scientific research in our own laboratory.

The election of Joseph John Thomson, professor of experimental physics and director of the Cavendish Laboratory, to the vacated post came as a surprise to many professors and scientists. At that time he was only twenty-seven years old, he was a mathematician by specialty, and did not make any noticeable discoveries in experimental physics. The young scientist was just developing mathematical models, which, in his opinion, should reveal the structure of the atom, and continued Maxwell's research in the field of electromagnetism. After some time, it became clear that the choice of Thomson for this position was very successful, and Joseph John became one of the great directors of the Cavendish Laboratory.

The most popular studies of physicists at that time were the problems of electricity and magnetism. In their first laboratory work Joseph John decided to investigate the electrical conductivity of gases and the physical nature of the sources that generate field strengths. He began to study currents in rarefied gases.

Back in 1853, the talented French physicist A. Masson conducted an experiment by passing electrical discharges through a glass tube from which air had been pumped out. Subsequently, the English physicist William Crookes, using the same device, conducted many different experiments. In one of them, Crookes placed electrodes at opposite ends of the tube, and between them a turntable with blades. Under the influence of rays that were propagated by a negatively charged electrode - the cathode - the turntable rotated, which made it possible to assume that the cathode rays are actually a stream of microscopic particles with a small mass.

Crookes made other interesting observations. If on inner surface tubes deposited substances, and the gas was sufficiently rarefied, then under the action of cathode rays the glass walls of the tube near the anode fluoresced with green light.

Scientists have differing opinions about the nature of cathode rays. English physicists believed that cathode rays were a stream of charged particles, but many continental physicists, in particular German ones, based on the experiments of Heinrich Hertz, assumed that these rays were waves (oscillations) in an unknown weightless medium.

Interest in the study of cathode rays was fueled by the discovery of X-rays by Wilhelm Roentgen in 1895. Thomson became one of the most active researchers in this area of ​​physics.

Working with his brilliant assistant Ernest Rutherford, he discovered that exposure to X-rays increased the electrical conductivity of gases. Scientists published a famous paper in which they concluded that the resulting conductivity is very similar to ionic conductivity in solution during electrolysis.

In 1897, Thomson designed a tube similar to the Crookes tube. With its help, he measured the deviations of cathode rays in electric field. In it, the scientist used two plates, between which cathode rays passed. The voltage applied to the plates could be increased or decreased, and the higher the voltage, the greater the deviation of the cathode rays from a straight path.

As a result of the experiment, Thomson discovered the deflection of cathode rays under the influence of electric field. The famous scientist subsequently concluded that the direction of the deflection indicated that the constituent particles of the cathode rays carried a negative electrical charge.

Thomson's assumption was confirmed by the remarkable French experimental physicist Jean Perrin. He determined the sign of the electric charge of the constituent particles of cathode rays by directing them to a metal cylinder. As a result of the experiment, the cylinder turned out to be negatively charged.

Thomson also measured the speed of the cathode rays, which turned out to be less speed light by 2000 times, which provided further evidence in favor of the corpuscular nature of the rays. Subsequently, with the help of a similar experiment, the famous scientist was able to establish the mass and charge of the particles that made up the cathode rays.

Joseph John carried out theoretical calculations that were supposed to describe the movement of a charged particle under the influence of electric and magnetic fields. According to Thomson, the deviation of a particle from a straight trajectory depended on the ratio of its charge to mass.

Following this, the scientist conducted an experiment in which he deflected cathode rays using an electric field. Then using magnetic field these rays were deflected in the opposite direction so that they returned to their original position. In this way it was possible to determine the speed and ratio of the particle's charge to its mass.

Experiments brilliantly confirmed Thomson's theoretical conclusions. As a result of the experiment, it was found that the ratio of the particle's charge to its mass is almost 1000 times less than that of hydrogen ions (today it is known that the true ratio is approximately 1837: 1). Thomson assumed that the charge of the particles was equal in magnitude to the charge of the hydrogen ion, which by that time had been accurately calculated using experiments in the field of electrolysis. Since the hydrogen atom had zero charge, the assumption arose that the charge of open particles was equal in value and opposite in sign to the charge of the hydrogen ion.

Soon, the negatively charged particles described by Thomson were called “electrons.” The discovery of Joseph John Thomson became one of the most important discoveries in physics of the 19th century.

Later, using a device invented by Charles Wilson, it was possible to obtain the value of the electron charge. It turned out that it actually corresponds to the charge value of the hydrogen ion. Thomson's assumption was confirmed.

In 1906, Joseph John Thomson was awarded the Nobel Prize in Physics "in recognition of his distinguished services in the field of theoretical and experimental research conductivity of electricity in gases".

In his presentation speech on December 10, 1906, Professor J. P. Klason, President of the Royal Swedish Academy of Sciences, thanked the scientist for his work, which allowed modern physicists to take research in new directions. Klason also stated that Thomson rightfully ranks with such scientific geniuses as Faraday and Maxwell.

In his Nobel lecture “Negative Charge Carriers,” delivered on December 11, 1906, the scientist analyzed in detail his discovery of electrons.

After receiving the Nobel Prize, Thomson continued his scientific research. In addition to the discovery of the electron, he made many other important discoveries for science.

In his early works, the English scientist studied the electromagnetic field of a moving charged ball, the theory of vortices, and carried out precision measurements of the ratio of absolute electrical units to electromagnetic units.

In his works “Electricity and Matter”, “Matter and Ether”, “The Structure of Light”, “Faraday's Force Tubes and Maxwell's Equations” Thomson consistently developed the vortex theory of matter and interactions.

The scientist’s famous work “Treatise on the Motion of Vortex Rings” was awarded the Adams Prize in 1884. Based on the vortex theory of the ether, Thomson derived the formula E= mc 2 long before Einstein.

In 1886, his famous work “Application of Dynamics in Physics and Chemistry” was published, and in 1892 the scientist published his new job"Notes on Recent Researches in Electricity and Magnetism". This work is often called "Maxwell's third volume". Together with Professor Poynting, Thomson wrote a four-volume textbook on physics, and in 1895 published the work “Elements mathematical theory electricity and magnetism”, which went through several reprints and translations into various languages ​​of the world.

After the discovery of the electron in 1897, Thomson proposed his model of the atom. The eminent scientist suggested that the atom consists of a positively charged fuzzy sphere interspersed with small negatively charged particles - electrons. Under the influence of Coulomb forces, electrons are located near the center of the atom, and if, as a result of some action, the particles deviate from the equilibrium position, then Coulomb forces restore their original state. Thomson's model received the humorous nickname "plum pudding" or "pudding model" among scientists.

However, in 1910, the brilliant physicist Ernest Rutherford, Thomson's former assistant, together with his students Geiger and Marsden, conducted a series of experiments, as a result of which they showed the fallacy of Thomson's model. Rutherford proposed a new, so-called “planetary” model of the atom. According to Rutherford, at the center of the atom, like the Sun, there is a positively charged nucleus, and negatively charged electrons rotate around the nucleus in circular orbits. Electrons are subject to centrifugal force, which is balanced by the electrostatic attraction of the electron to the nucleus. The model proposed by Rutherford forced Thomson to admit the fallacy of his model of the atom. Later, another brilliant physicist, Niels Bohr, improved Rutherford's model, suggesting that electrons are located around the nucleus in strictly defined orbits.

After a series of successful works leading to the discovery of electrons and their properties, in 1899 Thomson discovered electrons in photocurrent and also observed the effect of thermionic emission. In addition, the scientist explained the continuous spectrum of X-ray radiation.

Thanks to his subsequent work, Joseph John Thomson became one of the founders of the electronic theory of metals. In 1900, he derived a formula for the effective cross section for the scattering of electromagnetic waves by free electrons (Thomson's formula). A year after proposing the model of the atom, in 1904, Thomson proposed that the electrons in an atom were arranged in groups of different configurations. This phenomenon determines the periodicity of chemical elements.

Since 1905, Thomson had been interested in “channel rays”—fast moving particles produced behind the cathode of a gas discharge tube. The scientist discovered many of their characteristics, and also identified the types of atoms and atomic groups in these rays.

Modern mass spectrometry is based on Thomson's ideas.

In 1911, an English scientist developed the parabola method to measure the ratio of a particle's mass to its charge. And the very next year, using this method, he discovered the first isotopes. The scientist obtained neon atoms with masses 20 and 22. Thomson's discovery played an important role in understanding the nature of radioactive elements (such as uranium, radium).

In 1896, Thomson visited the United States and gave a course of four lectures at Princeton, in which he summarized his research. (It was upon his return from America that he made the famous discovery of electrons, which he told the whole world at his evening lecture at the Royal Institution on April 30, 1897.)

In 1904, Thomson again traveled to America, where he gave six lectures on electricity and matter at Yale University.

For my long scientific life the scientist wrote many textbooks, monographs and works that became classics during his lifetime.

During the First World War, the Nobel laureate worked in the Office of Research and Invention and was an adviser to the government.

In 1918, Thomson resigned, leaving his post as professor of experimental physics at the University of Cambridge and part-time director of the Cavendish Laboratory, where he made almost all of his ingenious discoveries. In the same year, he resigned from the Royal Institution in London, where he had worked since 1905.

The scientist worked at the university and laboratory for about 35 years. During this time he made many important discoveries, and the Cavendish Laboratory became one of the largest research centers in which the best physicists in the world dreamed of working.

The following year, Thomson was replaced in these positions by his assistant Ernest Rutherford, and the Nobel laureate himself became head of Trinity College, Cambridge University.

Since 1884, the scientist was a member of the Royal Society of London, and from 1916 to 1920 - its president. In 1909, the scientist became president of the British Association of Scientists.

In 1890, at the age of 34, the famous scientist married Rose Elizabeth Paget, daughter of Sir George Paget, professor of physics at Cambridge University. The couple had two children - daughter Joanna and son George.

The scientist's son, George Paget Thomson, later became famous physicist, Professor at the University of London. In 1937, he also won the Nobel Prize in Physics, which he received for his experimental discovery of electron diffraction by crystals.

Joseph John Thompson was a staunch supporter of classical physics and adhered to the theory of the ether. He received quantum theory, like the theory of relativity, coldly and changed his mind only after his son experimentally discovered the wave properties of electrons.

Besides the fact that Thomson was the greatest classical physicist who made revolutionary scientific discoveries, he became the founder of an international scientific school of physicists. Being an excellent leader and qualified teacher, Thomson educated and revealed the talents of many aspiring physicists. Such scientific geniuses as E. Rutherford, C. Wilson, F.W. Aston, W. Richardson, and P. Langevin worked under his leadership. Of those assistants who worked under his leadership at the Cavendish Laboratory, seven received Nobel Prizes.

The famous scientist Max Born (who would also become a Nobel laureate in the future) wrote that he felt the charm of the personality of Joseph John Thomson through his own example.

In addition to the Nobel Prize, Thomson was awarded various prizes and awards, among which are the awards of the Royal Society of London - the Royal Medal (1894), the Hughes Medal (1902) and the Copley Medal (1914), as well as the Hodgkins Medal of the Smithsonian University in Washington (1902), B. Franklin medal (1923), Mescart medal (1927), Dalton medal (1931), M. Faraday medal (1938).

Thomson was a member of various academies and scientific societies. He was awarded an honorary doctorate by the universities of Oxford, Cambridge, Dublin, London, Göttingen, Oslo, Paris, Edinburgh, Princeton, Athens, Krakow and others.

Since 1913, Thomson was a foreign honorary corresponding member of the St. Petersburg Academy of Sciences, and since 1925, a foreign honorary member of the USSR Academy of Sciences.

In 1908, the famous scientist was elevated to the rank of knight, and in 1912, Sir Joseph John Thomson was awarded the Order of Merit.

In October 1934, the Institute of Electrical Engineering produced a film in which Joseph John Thomson talks about his famous opening electron.

In his spare time, Joseph John loved to work in the garden and take long walks in nature.

John Joseph Thomson died on August 30, 1940 at the age of 83 and was buried on September 4 in Westminster Abbey in London, not far from Isaac Newton.