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Antoine Lavoisier
In Considérations Générales sur la Nature des Acides (1778), he demonstrated that the "air" responsible for combustion was also the source of acidity. The next year, he named this portion oxygen (Greek for acid-former), and the other azote (Greek for no life). He also discovered that the inflammable air of Cavendish which he termed hydrogen (Greek for water-former), combined with oxygen to produce a dew, as Priestley had reported, which appeared to be water. -
Antoine Lavoisier
In Methods of Chemical Nomenclature (1787), he invented the system of chemical nomenclature still largely in use today, including names such as sulfuric acid, sulfates, and sulfites -
J.L. Proust
the relative quantities of any given pure chemical compound’s constituent elements remain invariant, regardless of the compound’s source. This is known as Proust’s law, or the law of definite proportions (1793), and it is the fundamental principle of analytical chemistry. -
J.L. Proust
By doing this, he recognized that the proportions of the components of a chemical compound are always the same, no matter what method he used to prepare the compound. Proust announced this discovery in 1794, although many chemists of his day did not accept this finding. Berthollet became his main opponent in what became a famous controversy. -
John Dalton
In 1801, he observed and discovered the law of expansion of gases on heating. He also enunciated the law of partial pressures and found methods of determining vapour pressure of gases. He invented the dew point hygrometer. -
Thomas Young
While pursuing his interests in the function of the human eye, Young discovered the cause of astigmatism in 1801, which was about the time that he began his study of light. -
Thomas Young
1801, Young began a series of experiments that addressed a phenomenon known as interference. He observed that when light from a single source is separated into two beams, and the two beams are recombined, the combined beams produce a pattern of light and dark fringes. Young concluded that these fringes were the result of the beams of light behaving as waves with their peaks and troughs either reinforcing one another or canceling each other. When this occurred, alternating lines of light and da -
Thomas Young
In 1802 Young first demonstrated a simple proof of the wave theory of light. He forced the light from a single light source to pass through a narrow slit and then forced that same light to pass through two more narrow slits placed within a fraction of an inch of each other. The light from the two slits fell on a screen. Young found that the light beams spread apart and overlapped, and, in the area of overlap, bands of bright light alternated with bands of darkness. -
John Dalton
In 1803, he gave the famous atomic theory. He calculated, the atomic weight of many elements, invented chemical symbols, established the Law of multiple proportions and gave the correct formula for ether.He explained the nature of aurora borealis and suggested that the atmosphere contained a magnetic constituent -
Heinrich Hertz
In preparation for these he spent the winter of 1877-78 in reading up original treatises like those of Laplace and Lagrange on mathematics and mechanics, and in attending courses on practical physics under P. G. von Jolly and J. F. W. von Bezold; the consequence was that within a few days of his arrival in Berlin in October 1878 he was able to plunge into original research on a problem of electric inertia -
Heinrich Hertz
Later in 1880 he became assistant to Helmholtz in the physical laboratory of the Berlin Institute. During the three years he held this position he carried out researches on the contact of elastic solids, hardness, evaporation and the electric discharge in gases, the last earning him the special commendation of Helmholtz -
Heinrich Hertz
It was of course well known, as a necessity of Maxwell's mathematical theory, that the polarization and depolarization of an insulator must give rise to the same electromagnetic effects in the neighborhood as a voltaic current in a conductor. The experimental proof, however, was still lacking, and though several experimenters had come very near its discovery, Hertz was the first who actually succeeded in supplying it, in 1887. -
Marie and Pierre Curie
Persuaded by his father and by Marie, Pierre submitted his doctoral thesis in 1895. It concerned various types of magnetism, and contained a presentation of the connection between temperature and magnetism that is now known as Curie's Law. -
Marie and Pierre Curie
Pierre had managed to arrange that Marie should be allowed to work in the school's laboratory, and in 1897, she concluded a number of investigations into the magnetic properties of steel on behalf of an industrial association -
Marie and Pierre Curie
On December 26, 1898, that they had demonstrated strong grounds for having come upon an additional very active substance that behaved chemically almost like pure barium. They suggested the name of radium for the new element. -
Max Planck
Planck was able to deduce the relationship between the ener gy and the frequency of radiation. In a paper published in 1900, he announced his derivation of the relationship: this was based on the revolutionary idea that the energy emitted by a resonator could only take on discrete values or quanta. The energy for a resonator of frequency v is hv where h is a universal constant, now called Planck's constant. -
Marie and Pierre Curie
Won Nobel Prize in Physics in 1903 -
J.J Thomson
For his theoretical and experimental investigations into the electron and the conduction of electricity by gases he was awarded the 1906 Noble prize in Physics. -
Ernest Rutherford
Won Nobel Peace Price in 1908 -
Hans Geiger
Won a Nobel Prize for Chemistry in 1908. -
Ernest Marsden
In 1909, the final year of his degree course, Marsden was assigned to work with Rutherford's research assistant, Hans Geiger, to undertake experiments on the particles emitted during radioactive decay. They confirmed that the heavier, positively charged alpha particles passed straight through thin metal foils, but Rutherford suggested that Marsden check whether any were deflected back -
Ernest Rutherford
He is well known for the scattering experiment of alpha rays through matter, which led to the famous structure of atom in 1911 -
Hans Geiger
In 1911, also while working with Rutherford, Geiger created a measuring device that had the ability to count the number of alpha particles and other ionizing radiation being emitted. -
Niels Bohr
Bohr created the Bohr Model for electron placement. -
Albert Einstein
Albert Einstein extends his Special Theory to describe gravity as an inherent property of four- dimensional spacetime. The theory correctly explains a gradual shift in the orbit of the planet Mercury. -
Arthur Compton
He developed a theory of the intensity of X-ray reflection from crystals as a means of studying the arrangement of electrons and atoms, and in 1918 he started a study of X-ray scattering. -
Max Planck
Won Nobel Prize in Physics in 1918 -
Albert Einstein
According to Einstein's General Relativity, gravity warps space and deflects light beams. An expedition mounted by the Royal Astronomical Society sees the predicted effect under the ideal conditions of a solar eclipse. The confirmation makes Einstein famous. -
Wolfgang Pauli
He had further consolidated field theory by giving proof of the relationship between spin and"statistics" of elementary particles. He has written many articles on problems of theoretical physics, mostly quantum mechanics, in scientific journals of many countries, -
Niels Bohr
Niels Bohr was awarded the Nobel Prize in Physics at the young age of 37, in 1922, primarily for his work on atoms -
Arthur Compton
The American physicist Arthur Holly Compton observes that in their interactions with electrons, X rays behave like miniature billiard balls, further evidence for the reality of the photon. -
Louis de Broglie
French physicist Louis de Broglie generalizes wave-particle duality by suggesting that particles of matter are also wave- like. -
Paul Dirac
He began work on the new quantum mechanics as soon as it was introduced by Heisenberg in 1925 - independently producing a mathematical equivalent which consisted essentially of a noncommutative algebra for calculating atomic properties -
Enrico Fermi
In 1926, Fermi discovered the statistical laws, nowadays known as the «Fermi statistics», governing the particles subject to Pauli's exclusion principle (now referred to as «fermions», in contrast with «bosons» which obey the Bose-Einstein statistics). -
Erwin Schrodinger
The Austrian physicist Erwin Schrödinger describes the wave nature of matter by a formula called the Schrödinger equation, which becomes a cornerstone of quantum mechanics -
Arthur Compton
Compton was awarded the Nobel Prize in Physics for 1927 (sharing this with C. T. R. Wilson who received the Prize for his discovery of the cloud chamber method). -
Werner Heisenberg
In 1927 Heisenberg states his quantum Uncertainty Principle, that it is impossible to exactly measure the position and momentum of a particle at the same time -
Paul Dirac
This latter theory required the existence of a positive particle having the same mass and charge as the known (negative) electron. This, the positron was discovered experimentally at a later date (1932) by C. D. Anderson, while its existence was likewise proved by Blackett and Occhialini (1933 ) in the phenomena of "pair production" and "annihilation". -
Hans Geiger
In 1928 he co-invented the Geiger Counter, a much more portable machine to count alpha particles, with fellow physicist Walther Müller -
Louis de Broglie
Won The Noble Prize in Physics in 1929 -
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Arthur Compton
During 1930-1940, Compton led a world-wide study of the geographic variations of the intensity of cosmic rays, thereby fully confirming the observations made in 1927 by J. Clay from Amsterdam of the influence of latitude on cosmic ray intensity. -
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Louis de Broglie
Between 1930 and 1950, Louis de Broglie's work has been chiefly devoted to the study of the various extensions of wave mechanics: Dirac's electron theory, the new theory of light, the general theory of spin particles, applications of wave mechanics to nuclear physics, etc. -
Carl Anderson
The American physicist Carl D. Anderson examines the trails left by cosmic ray particles in a cloud chamber. He discovers the track of a positive electron, or positron, whose existence was predicted in 1928 by the Dirac Equation. -
James Chadwick
In 1932, he made the fundamental discovery of neutron, proving that it was the most powerful particle for initiating nuclear reactions. By energy calculations he was able to calculate the mass of the neutron. H -
Werner Heisenburg
For this theory and the applications of it which resulted especially in the discovery of allotropic forms of hydrogen, Heisenberg was awarded the Nobel Prize for Physics for 1932. -
Werner Heisenberg
His new theory was based only on what can be observed, that is to say, on the radiation emitted by the atom. We cannot, he said, always assign to an electron a position in space at a given time, nor follow it in its orbit, so that we cannot assume that the planetary orbits postulated by Niels Bohr actually exist. Mechanical quantities, such as position, velocity, etc. should be represented, not by ordinary numbers, but by abstract mathematical structures called "matrices" and he formulated his n -
Carl
In 1933 Carl Anderson and Dr. Neddermeyer obtained the first direct proof that gamma rays from ThC" generate positrons in their passage through material substances. -
Paul Dirac
Won Nobel Prize in Physics in 1933 -
Edwin Schrodinger
It came as a result of his dissatisfaction with the quantum condition in Bohr's orbit theory and his belief that atomic spectra should really be determined by some kind of eigenvalue problem. For this work he shared with Dirac the Nobel Prize for 1933. -
Enrico Fermi
Following the discovery by Curie and Joliot of artificial radioactivity (1934), he demonstrated that nuclear transformation occurs in almost every element subjected to neutron bombardment. This work resulted in the discovery of slow neutrons that same year, leading to the discovery of nuclear fission and the production of elements lying beyond what was until then the Periodic Table -
James Chadwick
He was awarded the Nobel Prize in Physics in 1935, for the discovery of neutron. -
Irene Joliot-Curie
Either alone or in collaboration with her husband, she did important work on natural and artificial radioactivity, transmutation of elements, and nuclear physics; she shared the Nobel Prize in Chemistry for 1935 with him, in recognition of their synthesis of new radioactive elements, which work has been summarized in their joint paper Production artificielle d'éléments radioactifs. Preuve chimique de la transmutation des éléments (1934). -
Carl Anderson
Carl Anderson and Victor Francis Hess received a Nobel Prize for Physics in 1936 for discovering positrons, positively charged particles the same size as electrons. -
Enrico Fermi
The Nobel Prize for Physics was awarded to Fermi for his work on the artificial radioactivity produced by neutrons, and for nuclear reactions brought about by slow neutrons. -
Irene Joliot-Curie
In 1938 her research on the action of neutrons on the heavy elements, was an important step in the discovery of uranium fission -
Lise Meitner and Otto Hahn and Fritz Strassman
In 1938 Otto Hahn, Lise Meitner, and Fritz Strassmann became the first to recognize that the uranium atom, when bombarded by neutrons, actually split. -
Otto Frisch
Working with the physicist Rudolf Peierls, he demonstrated that the fissioning of uranium had the potential to create a volatile chain reaction which, when using uranium-235, could be used to develop an extremely destructive weapon. -
Otto Frisch
In December 1939, Lise Meitner, who was living in exile in Stockholm, informed the visiting Frisch that Otto Hahn and Fritz Strassmann had found the phenomenon that strongly suggested the nuclear fission of uranium by bombardment (slow) neutrons. Hahn and Strassmann in Berlin had discovered that the collision of a neutron with a uranium nucleus produced the element barium as one of its byproducts. Frisch and Meitner explained the process in terms of excessive electrical charge, estimated the ene -
Richard Feynman and Julian Schwinger
He first approached electromagnetic radar problems as a nuclear physicist, but soon began to think of nuclear physics in the language of electrical engineering. That would eventually emerge as the effective range formulation of nuclear scattering. Then, being conscious of the large microwave powers available, Schwinger began to think about electron accelerators, which led to the question of radiation by electrons in magnetic fields. In studying the latter problem he was reminded, at the classica -
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Richard Feynman and Julian Schwinger
In subsequent years, he worked in a number of directions, but there was a pattern of concentration on general theoretical questions rather than specific problems of immediate experimental concern, which were nearer to the center ot hls earlier work. A speculative approach to physics has its dangers, but it can have its rewards. Schwinger was particularly pleased by an anticipation, early in 1957, of the existence of two different neutrinos associated, respectively, with the electron and the muon -
Lise Meitner and Otto Hahn and Fritz Strassman,
At the end of the war Hahn was astonished to hear that he had won the Nobel Prize for chemistry in 1944 and that nuclear bombs had been developed from his basic discovery. -
Wolfgang Pauli
Pauli helped to lay the foundations of the quantum theory of fields and he participated actively in the great advances made in this domain around 1945. -
Wolfgang Pauli
Won Nobel Prize in Physics in 1945 -
Enrico Fermi
In 1944, Fermi became American citizen, and at the end of the war (1946) he accepted a professorship at the Institute for Nuclear Studies of the University of Chicago, a position which he held until his untimely death in 1954. There he turned his attention to high-energy physics, and led investigations into the pion-nucleon interaction. -
Niels Bohr
In 1957, he was awarded the prize for 'Atom for Peace'. Structure -
Werner Heinseberg
From 1957 onwards Heisenberg was interested in work on problems of plasma physics and thermonuclear processes, and also much work in close collaboration with the International Institute of Atomic Physics at Geneva -
Murray Gell-Mann and George Zweig
Murray Gell-Mann and George Zweig tentatively put forth the idea of quarks. They suggested that mesons and baryons are composites of three quarks or antiquarks, called up, down, or strange (u, d, s) with spin 0.5 and electric charges 2/3, -1/3, -1/3, respectively (it turns out that this theory is not completely accurate) -
Richard Feynman and Julian Schwinger
Won Nobel Prize in Physics in 1965 -
Murray Gell-Mann
Won Nobel Prize in Physics in 1969
