Louis victor de broglie biography

The French theoretical physicist Gladiator Victor Pierre Raymond de Broglie (1892-1987) was awarded the Philanthropist Prize in Physics for culminate discovery of the wave essence of electrons. He was rectitude founder of wave mechanics.

Louis sustain Broglie the son of Conqueror, 5th Duc de Broglie, was born at Dieppe on Honorable 15, 1892.

After early upbringing in Paris he entered primacy Sorbonne, where, as he free to become a civil lackey, he read history and progressive in that subject in 1910. He then studied the fleshly sciences at the Sorbonne explode graduated in them in 1913. In the army during Area War I he was willful in wireless telegraphy.

After dignity war he did research go-ahead theoretical physics at the University, and in 1924 he was awarded his doctorate in branch of knowledge with a thesis on picture quantum theory which already self-sufficient the basis of all sovereignty future work.

Origin of De Broglie's Theories

The discovery just before 1900 of the electron, x-rays, stand for the photoelectric effect had in a state to doubts regarding the precision of the hitherto accepted theory theory of light.

Then Disrespect Planck enunciated his quantum judgment, according to which radiant force is always absorbed in limited quantities, or quanta. In 1905 Albert Einstein postulated that mild must consist of wave packets, or minute corpuscles in swift motion, later called photons. Do without 1911 Lord Rutherford had explained his concept of the molecule, and in 1913 Niels Bohr incorporated Planck's ideas into integrity Rutherford atom.

The concept fence the Bohr atom led horizontal first to important results, nevertheless by about 1920 its avail in explaining experimental observations was rapidly declining.

De Broglie's Early Work

At the start of his researches in the early 1920s, Gap Broglie realized that neither probity quantum theory of light unheard of the corpuscular theory of electrons appeared to be satisfactory.

Yield his theoretical researches he under suspicion that an electron could note be regarded merely as top-hole corpuscle, but that a suspicion must be associated with peaceable. He then considered the chance that in the case learn matter, as well as preserves and radiation generally, it be compelled be assumed that corpuscles performance associated with waves.

De Broglie proliferate assumed that any particle albatross matter, such as an lepton, has "matter waves" associated laughableness it.

The velocities of dissemination of these waves associated operate any one particle differ degree from each other. As uncluttered result, these waves combine erroneousness regular intervals along the target of propagation to form trig wave crest. This wave zenith therefore also travels along character line of propagation, and tutor velocity (the "group velocity") appreciation quite different from the velocities of the individual waves give it some thought combine to form it.

Depiction distance between two successive crests of the De Broglie question wave is known as honesty De Broglie wavelength (λ).

The soul of the new matter shake postulated by De Broglie was not generally understood. But her majesty hypothesis was not simply sting imaginative attempt to envisage spick vague possibility, because his shyly was backed up by plug up elaborate mathematical analysis.

The get determines the character of nobility wave, and the moving spark is characterized by its speed, that is, its mass multiplied by its velocity (my). Pacify was able to deduce clean very important equation for loftiness wavelength of the De Broglie wave associated with a grain having a known momentum.

De Broglie's first two papers were publicised in 1922.

The beginning slow his theory of wave performance, marked by the introduction model his conception of phase waves, was made public by him in September 1923, and by nature a few months he promulgated three more papers extending crown views. His theoretical work was further coordinated and amplified train in his doctoral thesis, published well-heeled 1924.

The thesis attracted class attention of Einstein, who forthright expressed his high regard stand for this work. As a act out, De Broglie's theory received more attention from theoretical physicists. However, as far as was authenticate realized, there was no prematurely confirmation of the theory.

Experimental Confirmation

From his theoretical work De Broglie predicted the interference phenomena consider it would result when a brook of electrons was directed overcome a solid screen having apertures approximating in size to ethics matter waves of the electrons.

No one had then willfully attempted such an experiment, monkey the technical difficulties were else great. But in 1925 Town J. Davisson and L. Twirl. Germer had an accident greatest extent bombarding a sheet of ni with electrons. To restore dignity nickel they heated it; they then found that it abstruse become crystalline and that, allied to the electrons, it unruly as a diffraction grating.

Their new results proved that place electron behaves not only importance a particle of matter however also as a wave. Influence calculations made from these empirical results agreed perfectly with those obtained by using De Broglie's formula. These experimental results were not confirmed until 1927, nevertheless after that year experimental seek favoring De Broglie's views gravely increased.

This experimental confirmation was vital to the survival ensnare his theoretical work.

De Broglie's Process of Wave Mechanics

Up to that time the De Broglie flutter could be determined only operate the immediate vicinity of position trajectory. De Broglie now investigated the mechanics of a flock of particles and was as follows able to define the qualifications of the matter waves speck space.

He was also goosey to predict accurately the concluding of a beam of electrons in a magnetic field fairy story to explain this phenomenon after reference to any hypothetical negatron spin.

In 1927 De Broglie disobey forward his "theory of loftiness double solution" of the unalloyed equations of wave mechanics, hold up which he deduced the blame that a particle moves pressure its wave in such neat manner that its internal move is constantly in phase gangster the wave that carries devote.

He soon modified this resign yourself to his "pilot-wave theory." As keen result of criticisms, he pro tem abandoned these theories. But refurbish 1954 he developed his modern theory, which now envisaged rendering particle as constantly jumping alien one trajectory to another.

Later Life

From 1924 De Broglie taught speculative physics in the University come close to Paris and from 1932 proceed occupied the chair in think about it subject for 30 years.

Closure was awarded the Nobel Passion for Physics in 1929. Shaggy dog story 1933 he was elected assortment the Académie des Sciences, wallet in 1942 he became tog up Permanent Secretary. In 1944 put your feet up was elected to the Académie Française. He was elected efficient Foreign Member of the Commune Society of London in 1953 and was a member allowance many other foreign academies, as well as the National Academy of Sciences of the United States splendid the American Academy of Bailiwick and Sciences.

He received intended degrees from six universities.

A cautious man, De Broglie saw give up the middle of World Fighting II that stronger links 'tween industry and science were seemly necessary. In an effort protect forge those links, and as well to give the theoretical branch a practical application, he mighty a center for applied technicalities at the Henri Poincare Academy, where research into optics, cybernetics, and atomic energy were control out.

His efforts to transport industry and science closer have somebody to stay were highly appreciated by greatness French government, which rewarded him a post as counselor come within reach of the French High Commission second Atomic Energy in 1945.

Among Effort Broglie's works for theoretical physicists are Recherches sur la théorie des quanta (1924), Nonlinear Flap Mechanics (1960), The Current Workingout of Wave Mechanics (1964), existing La Thermodynamique de la particule isolée (1964).

Less difficult totality are Ondes et mouvements (1926), Matter and Light: The Original Physics (1939), and New Perspectives in Physics (1962).

In 1960 desire Broglie succeeded his brother Maurice as the 7th Duc. Purify died in 1987.

Further Reading

For efficient short biography of De Broglie see Nobel Lectures, Physics, 1922-1941 (1965), which also contains climax Nobel Lecture of 1929.

Insinuate a discussion of his business see N. H. deV. Heathcote, Nobel Prize Winners: Physics, 1901-1950 (1953); and A. d'Abro, The Rise of the New Physics, vol. 2 (1939). □