Georgiy Antonovich Gamov
March 4, 1904 (O.S. February 20, 1904)
|Died||August 19, 1968 64) (aged|
Boulder, Colorado, United States
|Citizenship|| Soviet Union, |
|Alma mater||Leningrad State University|
|Known for|| Gamow factor |
Liquid drop model
One Two Three ... Infinity
|Awards||Kalinga Prize (1956)|
|Fields||Physicist, science writer|
|Institutions|| University of Göttingen |
Niels Bohr Institute
George Washington University
University of California, Berkeley
University of Colorado Boulder
|Doctoral advisor||Alexander Friedmann|
|Doctoral students|| Ralph Asher Alpher |
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George Gamow (March 4, 1904 – August 19, 1968), born Georgiy Antonovich Gamov, was a Soviet-American theoretical physicist and cosmologist. He was an early advocate and developer of Lemaître's Big Bang theory. He discovered a theoretical explanation of alpha decay via quantum tunneling, and worked on radioactive decay of the atomic nucleus, star formation, stellar nucleosynthesis and Big Bang nucleosynthesis (which he collectively called nucleocosmogenesis), and molecular genetics.
Russian Americans are Americans who trace their ancestry to Russia, the former Russian Empire, or the former Soviet Union. The definition can be applied to recent Russian immigrants to the United States, as well as to settlers of 19th-century Russian settlements in northwestern America.
Theoretical physics is a branch of physics that employs mathematical models and abstractions of physical objects and systems to rationalize, explain and predict natural phenomena. This is in contrast to experimental physics, which uses experimental tools to probe these phenomena.
Georges Henri Joseph Édouard Lemaître, RAS Associate was a Jesuit trained Belgian Roman Catholic priest, mathematician, astronomer, and professor of physics at the Catholic University of Louvain. He was the first to identify that the recession of nearby galaxies can be explained by a theory of an expanding universe, which was observationally confirmed soon afterwards by Edwin Hubble. He was the first to derive what is now known as Hubble's law, or the Hubble-Lemaître law, and made the first estimation of what is now called the Hubble constant, which he published in 1927, two years before Hubble's article. Lemaître also proposed what later became known as the "Big Bang theory" of the origin of the universe, initially calling it the "hypothesis of the primeval atom".
In his middle and late career, Gamow directed much of his attention to teaching and wrote popular books on science, including One Two Three... Infinity and the Mr Tompkins ... series of books (1939–1967). Some of his books are still in print more than a half-century after their original publication.
One Two Three... Infinity: Facts and Speculations of Science is a popular science book by theoretical physicist George Gamow, first published in 1947, exploring some fundamental concepts in mathematics and science, written at a level understandable by middle school students up through "intelligent layman" adults. The book is illustrated by Gamow.
Mr Tompkins is the title character in a series of four popular science books by the physicist George Gamow. The books are structured as a series of dreams in which Mr Tompkins enters alternative worlds where the physical constants have radically different values from those they have in the real world. Gamow aims to use these alterations to explain modern scientific theories.
Gamow was born in Odessa, Russian Empire. His father taught Russian language and literature in high school, and his mother taught geography and history at a school for girls. In addition to Russian, Gamow learned to speak some French from his mother and German from a tutor. Gamow learned fluent English in his college years and later. Most of his early publications were in German or Russian, but he later switched to writing in English for both technical papers and for the lay audience.
Odessa is the third most populous city of Ukraine and a major tourism center, seaport and transport hub located on the northwestern shore of the Black Sea. It is also the administrative center of the Odessa Oblast and a multiethnic cultural center. Odessa is sometimes called the "pearl of the Black Sea", the "South Capital", and "Southern Palmyra". Before the Tsarist establishment of Odessa, an ancient Greek settlement existed at its location as elsewhere along the northwestern Black Sea coast. A more recent Tatar settlement was also founded at the location by Hacı I Giray, the Khan of Crimea in 1440 that was named after him as "Hacıbey". After a period of Lithuanian Grand Duchy control, Hacibey and surroundings became part of the domain of the Ottomans in 1529 and remained there until the empire's defeat in the Russo-Turkish War of 1792.
The Russian Empire, also known as Imperial Russia or simply Russia, was an empire that extended across Eurasia and North America from 1721, following the end of the Great Northern War, until the Republic was proclaimed by the Provisional Government that took power after the February Revolution of 1917.
He was educated at the Institute of Physics and Mathematics in Odessa(1922–23) and at the University of Leningrad (1923–1929). Gamow studied under Alexander Friedmann for some time in Leningrad, until Friedmann's early death in 1925. He aspired to do his doctoral thesis under Friedmann, but had to change dissertation advisors. At the University, Gamow made friends with three other students of theoretical physics, Lev Landau, Dmitri Ivanenko, and Matvey Bronshtein. The four formed a group known as the Three Musketeers, which met to discuss and analyze the ground-breaking papers on quantum mechanics published during those years. He later used the same phrase to describe the Alpher, Herman, and Gamow group.
Odesa I. I. Mechnikov National University, located in Odessa, Ukraine, is one of the country's major universities, named after the scientist Élie Metchnikoff, a Nobel prizewinner in 1908. The university was founded in 1865, by an edict of Tsar Alexander II of Russia reorganizing the Richelieu Lyceum of Odessa into the new Imperial Novorossiya University. In the Soviet era, the University was renamed Odesa I. I. Mechnikov National University.
Saint Petersburg State University is a Russian federal state-owned higher education institution based in Saint Petersburg. It is the oldest and one of the largest universities in Russia.
Lev Davidovich Landau was a Soviet physicist who made fundamental contributions to many areas of theoretical physics.
On graduation, he worked on quantum theory in Göttingen, where his research into the atomic nucleus provided the basis for his doctorate. He then worked at the Theoretical Physics Institute of the University of Copenhagen from 1928 to 1931, with a break to work with Ernest Rutherford at the Cavendish Laboratory in Cambridge. He continued to study the atomic nucleus (proposing the "liquid drop" model), but also worked on stellar physics with Robert Atkinson and Fritz Houtermans.
Quantum mechanics, including quantum field theory, is a fundamental theory in physics which describes nature at the smallest scales of energy levels of atoms and subatomic particles.
Göttingen is a university city in Lower Saxony, Germany, the capital of the eponymous district. It is run through by River Leine. At the start of 2017, the population was 134,212.
The Niels Bohr Institute is a research institute of the University of Copenhagen. The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics.
In 1931, Gamow was elected a corresponding member of the Academy of Sciences of the USSR at age 28 – one of the youngest in the history of this organization.During the period 1931–1933, Gamow worked in the Physical Department of the Radium Institute (Leningrad) headed by Vitaly Khlopin . Europe's first cyclotron was designed under the guidance and direct participation of Igor Kurchatov, Lev Mysovskii and Gamow. In 1932, Gamow and Mysovskii submitted a draft design for consideration by the Academic Council of the Radium Institute, which approved it. The cyclotron was not completed until 1937.
A cyclotron is a type of particle accelerator invented by Ernest O. Lawrence in 1929–1930 at the University of California, Berkeley, and patented in 1932. A cyclotron accelerates charged particles outwards from the center along a spiral path. The particles are held to a spiral trajectory by a static magnetic field and accelerated by a rapidly varying electric field. Lawrence was awarded the 1939 Nobel prize in physics for this invention.
Igor Vasilyevich Kurchatov, was a Soviet nuclear physicist who is widely known as the director of the Soviet atomic bomb project. Along with Georgy Flyorov and Andrei Sakharov, Kurchatov is known as the "father of the Soviet atomic bomb" and, later, "the father of the Soviet Nuclear Missile" for his directorial role in a clandestine Soviet nuclear program formed during World War II in the wake of the USSR's discovery of the Western Allied efforts to develop nuclear weapons. After nine years of covert development, as well as Soviet spies successfully infiltrating the Manhattan Project, the Soviet Union successfully tested its first nuclear weapon, codenamed First Lightning at the Semipalatinsk Test Range in 1949. In 1954 he was awarded the USSR State Prize in physics.
In the early 20th century, radioactive materials were known to have characteristic exponential decay rates, or half-lives. At the same time, radiation emissions were known to have certain characteristic energies. By 1928, Gamow in Göttingen had solved the theory of the alpha decay of a nucleus via tunnelling, with mathematical help from Nikolai Kochin.The problem was also solved independently by Ronald W. Gurney and Edward U. Condon. Gurney and Condon did not, however, achieve the quantitative results achieved by Gamow.
Classically, the particle is confined to the nucleus because of the high energy requirement to escape the very strong nuclear potential well. Also classically, it takes an enormous amount of energy to pull apart the nucleus, an event that would not occur spontaneously. In quantum mechanics, however, there is a probability the particle can "tunnel through" the wall of the potential well and escape. Gamow solved a model potential for the nucleus and derived from first principles a relationship between the half-life of the alpha-decay event process and the energy of the emission, which had been previously discovered empirically and was known as the Geiger–Nuttall law.Some years later, the name Gamow factor or Gamow–Sommerfeld factor was applied to the probability of incoming nuclear particles tunnelling through the electrostatic Coulomb barrier and undergoing nuclear reactions.
Gamow worked at a number of Soviet establishments before deciding to flee the Soviet Union because of increased oppression. In 1931, he was officially denied permission to attend a scientific conference in Italy. Also in 1931, he married Lyubov Vokhmintseva (Russian : Любовь Вохминцева), another physicist in Soviet Union, whom he nicknamed "Rho" after the Greek letter. Gamow and his new wife spent much of the next two years trying to leave the Soviet Union, with or without official permission. Niels Bohr and other friends invited Gamow to visit during this period, but Gamow could not get permission to leave.
Gamow later said that his first two attempts to defect with his wife were in 1932 and involved trying to kayak: first a planned 250-kilometer paddle over the Black Sea to Turkey, and another attempt from Murmansk to Norway. Poor weather foiled both attempts, but they had not been noticed by the authorities.
In 1933, Gamow was suddenly granted permission to attend the 7th Solvay Conference on physics, in Brussels. He insisted on having his wife accompany him, even saying that he would not go alone. Eventually the Soviet authorities relented and issued passports for the couple. The two attended and arranged to extend their stay, with the help of Marie Curie and other physicists. Over the next year, Gamow obtained temporary work at the Curie Institute, University of London, and the University of Michigan.
In 1934, Gamow and his wife moved to the United States. He became a professor at George Washington University (GWU) in 1934 and recruited physicist Edward Teller from London to join him at GWU. In 1936, Gamow and Teller published what became known as the "Gamow–Teller selection rule" for beta decay. During his time in Washington, Gamow would also publish major scientific papers with Mário Schenberg and Ralph Alpher. By the late 1930s, Gamow's interests had turned towards astrophysics and cosmology.
In 1935, Gamow's son, Igor Gamow was born (in his 1947 book, Gamow's dedication was "To my son Igor, who wanted to be a cowboy"). George Gamow became a naturalized American in 1940. He retained his formal association with GWU until 1956.
During World War II, Gamow did not work directly on the Manhattan Project producing the atomic bomb, in spite of his knowledge of radioactivity and nuclear fusion. He continued to teach physics at GWU and consulted for the U.S. Navy.
Gamow was interested in the processes of stellar evolution and the early history of the Solar System. In 1945, he co-authored a paper supporting work by German theoretical physicist Carl Friedrich von Weizsäcker on planetary formation in the early Solar System.Gamow published another paper in the British journal Nature in 1948, in which he developed equations for the mass and radius of a primordial galaxy (which typically contains about one hundred billion stars, each with a mass comparable with that of the Sun).
Gamow's work led the development of the hot "big bang" theory of the expanding universe. He was the earliest to employ Alexander Friedmann's and Georges Lemaître's non-static solutions of Einstein's gravitational equations describing a universe of uniform matter density and constant spatial curvature. Gamow's crucial advance would provide a physical reification of Lemaître's idea of a unique primordial quantum. Gamow did this by assuming that the early universe was dominated by radiation rather than by matter.Most of the later work in cosmology is founded in Gamow's theory. He applied his model to the question of the creation of the chemical elements and to the subsequent condensation of matter into galaxies, whose mass and diameter he was able to calculate in terms of the fundamental physical parameters, such as the speed of light c, Newton's gravitational constant G, Sommerfeld's fine-structure constant α, and Planck's constant h.
Gamow's interest in cosmology arose from his earlier interest in energy generation and element production and transformation in stars.This work, in turn, evolved from his fundamental discovery of quantum tunneling as the mechanism of nuclear alpha decay, and his application of this theory to the inverse process to calculate rates of thermonuclear reaction.
At first, Gamow believed that all the elements might be produced in the very high temperature and density early stage of the universe. Later, he revised this opinion on the strength of compelling evidence advanced by Fred Hoyle et al. that elements heavier than lithium are largely produced in thermonuclear reactions in stars and in supernovae. Gamow formulated a set of coupled differential equations describing his proposed process and assigned, as a PhD. dissertation topic, his graduate student Ralph Alpher the task of solving the equations numerically. These results of Gamow and Alpher appeared in 1948 as the Alpher–Bethe–Gamow paper.Bethe later referred to this paper as being "wrong". Before his interest turned to the question of the genetic code, Gamow published about twenty papers on cosmology. The earliest was in 1939 with Edward Teller on galaxy formation, followed in 1946 by the first description of cosmic nucleosynthesis. He also wrote many popular articles as well as academic textbooks on this and other subjects.
In 1948, he published a paper dealing with an attenuated version of the coupled set of equations describing the production of the proton and the deuteron from thermal neutrons. By means of a simplification and using the observed ratio of hydrogen to heavier elements he was able to obtain the density of matter at the onset of nucleosynthesis and from this the mass and diameter of the early galaxies.In 1953 he produced similar results, but this time based on another determination of the density of matter and radiation at the point at which they became equal. In this paper Gamow determined the density of the relict background radiation from which a present temperature of 7K is trivially predicted – a value slightly more than twice the presently accepted value. In 1967 he published a reminder and recapitulation of his own work as well as that of Alpher and Robert Herman (both with Gamow and also independently of him). This was prompted by the discovery of the cosmic background radiation by Penzias and Wilson in 1965, for which Gamow, Alpher and Herman felt that they did not receive the credit they deserved for their prediction of its existence and source. Gamow was disconcerted by the fact that the authors of a communication explaining the significance of the Penzias/Wilson observations failed to recognize and cite the previous work of Gamow and his collaborators.
In 1953, Francis Crick, James Watson, Maurice Wilkins and Rosalind Franklin discovered the double helix structure of the DNA macromolecule. Gamow attempted to solve the problem of how the ordering of four different bases (adenine, cytosine, thymine and guanine) in DNA chains might control the synthesis of proteins from their constituent amino acids.Crick has said that Gamow's suggestions helped him in his own thinking about the problem. As related by Crick, Gamow observed that the 43 = 64 possible permutations of the four DNA bases, taken three at a time, would be reduced to 20 distinct combinations if the order was irrelevant. . Gamow proposed that these 20 combinations might code for the twenty amino acids which, he suggested, might well be the sole constituents of all proteins. Gamow's contribution to solving the problem of genetic coding gave rise to important models of biological degeneracy.
The specific system that Gamow was proposing (called "Gamow's diamonds") proved to be incorrect. The triplets were supposed to be overlapping, so that in the sequence GGAC (for example), GGA could produce one amino acid and GAC another, and also non-degenerate (meaning that each amino acid would correspond to one combination of three bases – in any order). Later protein sequencing work proved that this could not be the case; the true genetic code is non-overlapping and degenerate, and changing the order of a combination of bases does change the amino acid.
In 1954, Gamow and Watson co-founded the RNA Tie Club. This was a discussion group of leading scientists concerned with the problem of the genetic code, which counted among its members the physicists Edward Teller and Richard Feynman. In his autobiographical writings, Watson later acknowledged the great importance of Gamow's insightful initiative. However, this did not prevent him from describing this colorful personality as a "zany", card-trick playing, limerick-singing, booze-swilling, practical–joking "giant imp".
Gamow worked at George Washington University from 1934 until 1954, when he became a visiting professor at the University of California, Berkeley. In 1956, he moved to the University of Colorado Boulder, where he remained for the rest of his career. In 1956, Gamow became one of the founding members of the Physical Science Study Committee (PSSC), which later reformed teaching of high-school physics in the post-Sputnik years. Also in 1956, he divorced his first wife. Gamow later married Barbara Perkins (an editor for one of his publishers) in 1958.
In 1959, Gamow, Hans Bethe, and Victor Weisskopf publicly supported the re-entry of Frank Oppenheimer into teaching college physics at the University of Colorado, as the Red Scare began to fade (J. Robert Oppenheimer was the older brother of Frank Oppenheimer, and both of them had worked on the Manhattan Project before their careers in physics were derailed by McCarthyism). 130 While in Colorado, Frank Oppenheimer became increasingly interested in teaching science through simple hands-on experiments, and he eventually moved to San Francisco to found the Exploratorium. :130–152 Gamow would not live to see his colleague's opening of this innovative new science museum, in late August 1969. :152:
In his 1961 book The Atom and its Nucleus, Gamow proposed representing the periodic system of the chemical elements as a continuous tape, with the elements in order of atomic number wound round in a three-dimensional helix whose diameter increased stepwise (corresponding to the longer rows of the conventional periodic table).
Gamow was an atheist.
Gamow continued his teaching at the University of Colorado Boulder and focused increasingly on writing textbooks and books on science for the general public. After several months of ill health, surgeries on his circulatory system, diabetes and liver problems, Gamow was dying from liver failure, which he had called the "weak link" that could not withstand the other stresses.
In a letter written to Ralph Alpher on August 18, he had written, "The pain in the abdomen is unbearable and does not stop". Prior to this, there had been a long exchange of letters with his former student, in which he was seeking a fresh understanding of some concepts used in his earlier work, with Paul Dirac. Gamow relied on Alpher for deeper understanding of mathematics.
On August 19, 1968, Gamow died at age 64 in Boulder, Colorado, and was buried there in Green Mountain Cemetery. The physics department tower at the University of Colorado at Boulder is named after him.
Gamow was a highly successful science writer, with several of his books still in print more than a half-century after their initial publication. As an educator, Gamow recognized and emphasized fundamental principles that were unlikely to become obsolete, even as the pace of science and technology accelerated. He also conveyed a sense of excitement with the revolution in physics and other scientific topics of interest to the common reader. Gamow himself sketched the many illustrations for his books, which added a new dimension to and complemented what he intended to convey in the text. He was unafraid to introduce mathematics wherever it was essential, but he tried to avoid deterring potential readers by including large numbers of equations that did not illustrate essential points.
In 1956, he was awarded the Kalinga Prize by UNESCO for his work in popularizing science with his Mr. Tompkins... series of books (1939–1967), his book One, Two, Three...Infinity , and other works.
Before his death, Gamow was working with Richard Blade on a textbook Basic Theories in Modern Physics, but the work was never completed or published under that title. Gamow was also writing My World Line: An Informal Autobiography, which was published posthumously in 1970.
A collection of Gamow's writings was donated to The George Washington University in 1996. The materials include correspondence, articles, manuscripts and printed materials both by and about George Gamow. The collection is currently under the care of GWU's Special Collections Research Center, located in the Estelle and Melvin Gelman Library.
Throughout these books, Mr Tompkins is introduced as "C. G. H. Tompkins" to emphasize the notion of cGh physics.
George Gamow was the inspiration for Professor Gamma in the Professor Gamma series of science fiction books by Geoffrey Hoyle and his father astronomer Sir Fred Hoyle.
An atom is the smallest constituent unit of ordinary matter that has the properties of a chemical element. Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are extremely small; typical sizes are around 100 picometers.
Alpha decay or α-decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle and thereby transforms or 'decays' into a different atomic nucleus, with a mass number that is reduced by four and an atomic number that is reduced by two. An alpha particle is identical to the nucleus of a helium-4 atom, which consists of two protons and two neutrons. It has a charge of +2 e and a mass of 4 u. For example, uranium-238 decays to form thorium-234. Alpha particles have a charge +2 e, but as a nuclear equation describes a nuclear reaction without considering the electrons – a convention that does not imply that the nuclei necessarily occur in neutral atoms – the charge is not usually shown.
In nuclear physics, beta decay (β-decay) is a type of radioactive decay in which a beta ray is emitted from an atomic nucleus. For example, beta decay of a neutron transforms it into a proton by the emission of an electron accompanied by an antineutrino, or conversely a proton is converted into a neutron by the emission of a positron with a neutrino, thus changing the nuclide type. Neither the beta particle nor its associated (anti-)neutrino exist within the nucleus prior to beta decay, but are created in the decay process. By this process, unstable atoms obtain a more stable ratio of protons to neutrons. The probability of a nuclide decaying due to beta and other forms of decay is determined by its nuclear binding energy. The binding energies of all existing nuclides form what is called the nuclear band or valley of stability. For either electron or positron emission to be energetically possible, the energy release or Q value must be positive.
Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions. Other forms of nuclear matter are also studied. Nuclear physics should not be confused with atomic physics, which studies the atom as a whole, including its electrons.
Edward Teller was a Hungarian-American theoretical physicist who is known colloquially as "the father of the hydrogen bomb", although he did not care for the title. He made numerous contributions to nuclear and molecular physics, spectroscopy, and surface physics. His extension of Enrico Fermi's theory of beta decay, in the form of Gamow–Teller transitions, provided an important stepping stone in its application, while the Jahn–Teller effect and the Brunauer–Emmett–Teller (BET) theory have retained their original formulation and are still mainstays in physics and chemistry. Teller also made contributions to Thomas–Fermi theory, the precursor of density functional theory, a standard modern tool in the quantum mechanical treatment of complex molecules. In 1953, along with Nicholas Metropolis, Arianna Rosenbluth, Marshall Rosenbluth, and his wife Augusta Teller, Teller co-authored a paper that is a standard starting point for the applications of the Monte Carlo method to statistical mechanics. Throughout his life, Teller was known both for his scientific ability and for his difficult interpersonal relations and volatile personality.
Julius Robert Oppenheimer was an American theoretical physicist and professor of physics at the University of California, Berkeley. Oppenheimer was the wartime head of the Los Alamos Laboratory and is among those who are credited with being the "father of the atomic bomb" for their role in the Manhattan Project, the World War II undertaking that developed the first nuclear weapons. The first atomic bomb was successfully detonated on July 16, 1945, in the Trinity test in New Mexico. Oppenheimer later remarked that it brought to mind words from the Bhagavad Gita: "Now I am become Death, the destroyer of worlds." In August 1945, the weapons were used in the atomic bombings of Hiroshima and Nagasaki.
In physical cosmology, Big Bang nucleosynthesis refers to the production of nuclei other than those of the lightest isotope of hydrogen during the early phases of the Universe. Primordial nucleosynthesis is believed by most cosmologists to have taken place in the interval from roughly 10 seconds to 20 minutes after the Big Bang, and is calculated to be responsible for the formation of most of the universe's helium as the isotope helium-4 (4He), along with small amounts of the hydrogen isotope deuterium, the helium isotope helium-3 (3He), and a very small amount of the lithium isotope lithium-7 (7Li). In addition to these stable nuclei, two unstable or radioactive isotopes were also produced: the heavy hydrogen isotope tritium ; and the beryllium isotope beryllium-7 (7Be); but these unstable isotopes later decayed into 3He and 7Li, as above.
A timeline of atomic and subatomic physics.
Hans Albrecht Bethe was a German-American nuclear physicist who made important contributions to astrophysics, quantum electrodynamics and solid-state physics, and won the 1967 Nobel Prize in Physics for his work on the theory of stellar nucleosynthesis.
Ralph Asher Alpher was an American cosmologist, who carried out pioneering work in the early 1950s on the Big Bang model, including Big Bang nucleosynthesis and predictions of the cosmic microwave background radiation.
The nuclear force is a force that acts between the protons and neutrons of atoms. Neutrons and protons, both nucleons, are affected by the nuclear force almost identically. Since protons have charge +1 e, they experience an electric force that tends to push them apart, but at short range the attractive nuclear force is strong enough to overcome the electromagnetic force. The nuclear force binds nucleons into atomic nuclei.
Robert Herman was a United States scientist, best known for his work with Ralph Alpher in 1948-50, on estimating the temperature of cosmic microwave background radiation from the Big Bang explosion.
In physical cosmology, the Alpher–Bethe–Gamow paper, or αβγ paper, was created by Ralph Alpher, then a physics PhD student, and his advisor George Gamow. The work, which would become the subject of Alpher's PhD dissertation, argued that the Big Bang would create hydrogen, helium and heavier elements in the correct proportions to explain their abundance in the early universe. While the original theory neglected a number of processes important to the formation of heavy elements, subsequent developments showed that Big Bang nucleosynthesis is consistent with the observed constraints on all primordial elements.
In nuclear physics, the Geiger–Nuttall law or Geiger–Nuttall rule relates the decay constant of a radioactive isotope with the energy of the alpha particles emitted. Roughly speaking, it states that short-lived isotopes emit more energetic alpha particles than long-lived ones.
The B2FH paper, named after the initials of the authors of the paper, Margaret Burbidge, Geoffrey Burbidge, William A. Fowler, and Fred Hoyle, is a landmark paper on the origin of the chemical elements published in Reviews of Modern Physics in 1957. The title of that paper is "Synthesis of the Elements in Stars", but as that paper grew in influence, it came to be referred to only as "B2FH". The B2FH paper spread stellar nucleosynthesis theory widely in the scientific community, especially among astronomers who saw everyday relevance to their quest, at a time when it was appreciated by only a handful of experts in nuclear physics. But it did not create the theory of stellar nucleosynthesis as much as bring it vividly to life.
Ronald Wilfred Gurney was a British theoretical physicist and research pupil of William Lawrence Bragg at the Victoria University of Manchester during the 1920s and 1930s, Bristol University during the 1930s and later in the USA, where he died.
Charles Louis Critchfield was an American mathematical physicist. A graduate of George Washington University, where he earned his PhD in Physics under the direction of Edward Teller in 1939, he conducted research in ballistics at the Institute for Advanced Study in Princeton and the Ballistic Research Laboratory at the Aberdeen Proving Ground, and received three patents for improved sabot designs.
The discovery of the neutron and its properties was central to the extraordinary developments in atomic physics in the first half of the 20th century. Early in the century, Ernest Rutherford developed a crude model of the atom, based on the gold foil experiment of Hans Geiger and Ernest Marsden. In this model, atoms had their mass and positive electric charge concentrated in a very small nucleus. By 1920 chemical isotopes had been discovered, the atomic masses had been determined to be (approximately) integer multiples of the mass of the hydrogen atom, and the atomic number had been identified as the charge on the nucleus. Throughout the 1920s, the nucleus was viewed as composed of combinations of protons and electrons, the two elementary particles known at the time, but that model presented several experimental and theoretical contradictions.
A Fermi transition or a Gamow–Teller transition are types of nuclear beta decay determined by changes in angular momentum or spin. In the Fermi transition, the spins of the emitted particles are antiparallel, coupling to , so the angular momentum of the initial and final angular momentum states of the nucleus are unchanged. This is in contrast to a Gamow-Teller transition, where the spins of the emitted electron (positron) and antineutrino (neutrino) couple to total spin , leading to an angular momentum change between the initial and final angular momentum states of the nucleus.
After the initial mathematical work on relativity theory had been done, the Big Bang theory itself was invented by a Belgian priest, Georges Lemaître, improved upon by an avowed atheist, George Gamow, and is now all but universally accepted by those who hold advanced degrees in astronomy and the physical sciences, despite its obvious absurdity.
Surprisingly, the atheist George Gamow enjoyed the Papal attention given to his field of research.
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