Arthur Stanley Eddington

Arthur Stanley Eddington

Overview
Sir Arthur Stanley Eddington, OM, FRS
Royal Society
The Royal Society of London for Improving Natural Knowledge, known simply as the Royal Society, is a learned society for science, and is possibly the oldest such society in existence. Founded in November 1660, it was granted a Royal Charter by King Charles II as the "Royal Society of London"...

 (28 December 1882 – 22 November 1944) was a British astrophysicist of the early 20th century. He was also a philosopher of science
Philosophy of science
The philosophy of science is concerned with the assumptions, foundations, methods and implications of science. It is also concerned with the use and merit of science and sometimes overlaps metaphysics and epistemology by exploring whether scientific results are actually a study of truth...

 and a popularizer of science. The Eddington limit, the natural limit to the luminosity
Luminosity
Luminosity is a measurement of brightness.-In photometry and color imaging:In photometry, luminosity is sometimes incorrectly used to refer to luminance, which is the density of luminous intensity in a given direction. The SI unit for luminance is candela per square metre.The luminosity function...

 of stars, or the radiation generated by accretion onto a compact object, is named in his honour.

He is famous for his work regarding the Theory of Relativity
Theory of relativity
The theory of relativity, or simply relativity, encompasses two theories of Albert Einstein: special relativity and general relativity. However, the word relativity is sometimes used in reference to Galilean invariance....

. Eddington wrote a number of articles which announced and explained Einstein's
Albert Einstein
Albert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...

 theory of general relativity
General relativity
General relativity or the general theory of relativity is the geometric theory of gravitation published by Albert Einstein in 1916. It is the current description of gravitation in modern physics...

 to the English-speaking world.
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Quotations

We have found a strange footprint on the shores of the unknown. We have devised profound theories, one after another, to account for its origins. At last, we have succeeded in reconstructing the creature that made the footprint. And lo! It is our own.

Space, Time and Gravitation (1920)

Physics has in the main contented itself with studying the abridged edition of the book of nature.

"A Generalization of Weyl's Theory of the Electromagnetic and Gravitational Fields" in Proceedings of the Royal Society of London A99 (1921), p. 108

I think that science would never have achieved much progress if it had always imagined unknown obstacles hidden round every corner. At least we may peer gingerly round the corner, and perhaps we shall find there is nothing very formidable after all.

Stars and Atoms (1927); lecture 1

There once was a brainy baboon,Who always breathed down a bassoon,For he said, "It appearsThat in billions of yearsI shall certainly hit on a tune".

New Pathways in Science (1939)

It is also a good rule not to put overmuch confidence in the observational results that are put forward until they are confirmed by theory.

As quoted in "Annals of Science II-DNA" by Horace Freeland Judson|Horace Freeland Judson in The New Yorker|The New Yorker (4 December 1978), p. 132

We used to think that if we knew one, we knew two, because one and one are two. We are finding that we must learn a great deal more about 'and'.

As quoted in A Dictionary of Scientific Quotations (1991) by Alan L. Mackay, p. 79 :Published versions of his Gifford Lectures|Gifford Lectures delivered in the University of Edinburgh (January - March 1927)
Encyclopedia
Sir Arthur Stanley Eddington, OM, FRS
Royal Society
The Royal Society of London for Improving Natural Knowledge, known simply as the Royal Society, is a learned society for science, and is possibly the oldest such society in existence. Founded in November 1660, it was granted a Royal Charter by King Charles II as the "Royal Society of London"...

 (28 December 1882 – 22 November 1944) was a British astrophysicist of the early 20th century. He was also a philosopher of science
Philosophy of science
The philosophy of science is concerned with the assumptions, foundations, methods and implications of science. It is also concerned with the use and merit of science and sometimes overlaps metaphysics and epistemology by exploring whether scientific results are actually a study of truth...

 and a popularizer of science. The Eddington limit, the natural limit to the luminosity
Luminosity
Luminosity is a measurement of brightness.-In photometry and color imaging:In photometry, luminosity is sometimes incorrectly used to refer to luminance, which is the density of luminous intensity in a given direction. The SI unit for luminance is candela per square metre.The luminosity function...

 of stars, or the radiation generated by accretion onto a compact object, is named in his honour.

He is famous for his work regarding the Theory of Relativity
Theory of relativity
The theory of relativity, or simply relativity, encompasses two theories of Albert Einstein: special relativity and general relativity. However, the word relativity is sometimes used in reference to Galilean invariance....

. Eddington wrote a number of articles which announced and explained Einstein's
Albert Einstein
Albert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...

 theory of general relativity
General relativity
General relativity or the general theory of relativity is the geometric theory of gravitation published by Albert Einstein in 1916. It is the current description of gravitation in modern physics...

 to the English-speaking world. World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

 severed many lines of scientific communication and new developments in German science were not well known in England. He also conducted an expedition to observe the Solar eclipse of 29 May 1919
Solar eclipse of May 29, 1919
A total solar eclipse occurred on May 29, 1919. With a maximum duration of totality of 6 minutes 51 seconds, it was one of the longest solar eclipses of the 20th century. It was visible throughout most of South America and Africa as a partial eclipse...

 that provided one of the earliest confirmations of relativity, and he became known for his popular expositions and interpretations of the theory.

Early Years


Eddington was born in Kendal
Kendal
Kendal, anciently known as Kirkby in Kendal or Kirkby Kendal, is a market town and civil parish within the South Lakeland District of Cumbria, England...

, Cumbria
Cumbria
Cumbria , is a non-metropolitan county in North West England. The county and Cumbria County Council, its local authority, came into existence in 1974 after the passage of the Local Government Act 1972. Cumbria's largest settlement and county town is Carlisle. It consists of six districts, and in...

, England, the son of Quaker parents, Arthur Henry Eddington and Sarah Ann Shout. His father taught at a Quaker training college in Lancashire before moving to Kendal to become headmaster of Stramongate School. He died in the typhoid epidemic which swept England in 1884. His mother was left to bring up her two children with relatively little income. The family moved to Weston-super-Mare
Weston-super-Mare
Weston-super-Mare is a seaside resort, town and civil parish in the unitary authority of North Somerset, which is within the ceremonial county of Somerset, England. It is located on the Bristol Channel coast, south west of Bristol, spanning the coast between the bounding high ground of Worlebury...

 where at first Stanley (as his mother and sister always called Eddington) was educated at home before spending three years at a preparatory school.

In 1893 Stanley entered Brynmelyn School. He proved to be a most capable scholar particularly in mathematics and English literature. His performance earned him a scholarship to Owens College, Manchester (what was later to become the University of Manchester
University of Manchester
The University of Manchester is a public research university located in Manchester, United Kingdom. It is a "red brick" university and a member of the Russell Group of research-intensive British universities and the N8 Group...

) in 1898, which he was able to attend, having turned 16 that year. He spent the first year in a general course, but turned to physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...

 for the next three years. Eddington was greatly influenced by his physics and mathematics teachers, Arthur Schuster
Arthur Schuster
Sir Franz Arthur Friedrich Schuster FRS was a German-born British physicist known for his work in spectroscopy, electrochemistry, optics, X-radiography and the application of harmonic analysis to physics...

 and Horace Lamb
Horace Lamb
Sir Horace Lamb FRS was a British applied mathematician and author of several influential texts on classical physics, among them Hydrodynamics and Dynamical Theory of Sound...

. At Manchester, Eddington lived at Dalton Hall, where he came under the lasting influence of the Quaker mathematician J.W. Graham. His progress was rapid, winning him several scholarships and he graduated with a B.Sc. in physics with First Class Honours in 1902.

Based on his performance at Owens College, he was awarded a scholarship to the University of Cambridge (Trinity College) in 1902. His tutor at Cambridge was the distinguished mathematician R.A. Herman and in 1904 Eddington became the first ever second-year student to be placed as Senior Wrangler. After receiving his M.A. in 1905, he began research on thermionic emission
Thermionic emission
Thermionic emission is the heat-induced flow of charge carriers from a surface or over a potential-energy barrier. This occurs because the thermal energy given to the carrier overcomes the binding potential, also known as work function of the metal. The charge carriers can be electrons or ions, and...

 in the Cavendish Laboratory
Cavendish Laboratory
The Cavendish Laboratory is the Department of Physics at the University of Cambridge, and is part of the university's School of Physical Sciences. It was opened in 1874 as a teaching laboratory....

. This did not go well, and meanwhile he spent time teaching mathematics to first year engineering students. This hiatus was brief.

Astronomy


In January 1906, Eddington was nominated to the post of chief assistant to the Astronomer Royal
Astronomer Royal
Astronomer Royal is a senior post in the Royal Household of the Sovereign of the United Kingdom. There are two officers, the senior being the Astronomer Royal dating from 22 June 1675; the second is the Astronomer Royal for Scotland dating from 1834....

 at the Royal Greenwich Observatory. He left Cambridge for Greenwich the following month. He was put to work on a detailed analysis of the parallax
Parallax
Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines. The term is derived from the Greek παράλλαξις , meaning "alteration"...

 of 433 Eros
433 Eros
433 Eros is a near-Earth asteroid discovered in 1898, and the first asteroid to be orbited by a probe . It is an S-type asteroid approximately 34.4×11.2×11.2 km in size, the second-largest NEA after 1036 Ganymed, and belongs to the Amor group.Eros is a Mars-crosser asteroid, the first known...

 on photographic plate
Photographic plate
Photographic plates preceded photographic film as a means of photography. A light-sensitive emulsion of silver salts was applied to a glass plate. This form of photographic material largely faded from the consumer market in the early years of the 20th century, as more convenient and less fragile...

s that had started in 1900. He developed a new statistical method based on the apparent drift of two background stars, winning him the Smith's Prize
Smith's Prize
The Smith's Prize was the name of each of two prizes awarded annually to two research students in theoretical Physics, mathematics and applied mathematics at the University of Cambridge, Cambridge, England.- History :...

 in 1907. The prize won him a Fellowship of Trinity College, Cambridge. In December 1912 George Darwin
George Darwin
Sir George Howard Darwin, FRS was an English astronomer and mathematician.-Biography:Darwin was born at Down House, Kent, the second son and fifth child of Charles and Emma Darwin...

, son of Charles Darwin
Charles Darwin
Charles Robert Darwin FRS was an English naturalist. He established that all species of life have descended over time from common ancestry, and proposed the scientific theory that this branching pattern of evolution resulted from a process that he called natural selection.He published his theory...

, died suddenly and Eddington was promoted to his chair as the Plumian Professor of Astronomy and Experimental Philosophy
Plumian Professor of Astronomy and Experimental Philosophy
The Plumian chair of Astronomy and Experimental Philosophy is one of the two major Professorships in Astronomy at Cambridge University, alongside the Lowndean Professorship. The chair is currently held at the Institute of Astronomy in the University...

 in early 1913. Later that year, Robert Ball
Robert Stawell Ball
Sir Robert Stawell Ball was an Irish astronomer. He worked for Lord Rosse from 1865 to 1867. In 1867 he became Professor of Applied Mathematics at the Royal College of Science in Dublin. In 1874 Ball was appointed Royal Astronomer of Ireland and Andrews Professor of Astronomy in the University...

, holder of the theoretical Lowndean chair
Lowndean Professor of Astronomy and Geometry
The Lowndean chair of Astronomy and Geometry is one of the two major Professorships in Astronomy at Cambridge University, alongside the Plumian Professorship...

 also died, and Eddington was named the director of the entire Cambridge Observatory
Cambridge Observatory
Cambridge Observatory is an astronomical observatory at the University of Cambridge in the East of England. It was first established in 1823 and is now part of the site of the Institute of Astronomy...

 the next year. In May, 1914 he was elected a Fellow of the Royal Society and won their Royal Medal
Royal Medal
The Royal Medal, also known as The Queen's Medal, is a silver-gilt medal awarded each year by the Royal Society, two for "the most important contributions to the advancement of natural knowledge" and one for "distinguished contributions in the applied sciences" made within the Commonwealth of...

 in 1918 and delivered their Bakerian Lecture
Bakerian Lecture
The Bakerian Lecture is a prize lecture of the Royal Society, a lecture on physical sciences.In 1775 Henry Baker left £100 for a spoken lecture by a Fellow on such part of natural history or experimental philosophy as the Society shall determine....

 in 1926.

Eddington also investigated the interior of star
Star
A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...

s through theory, and developed the first true understanding of stellar processes. He began this in 1916 with investigations of possible physical explanations for Cepheid variables. He began by extending Karl Schwarzschild's earlier work on radiation pressure in Emden polytropic models. These models treated a star as a sphere of gas held up against gravity by internal thermal pressure, and one of Eddington's chief additions was to show that radiation pressure was necessary to prevent collapse of the sphere. He developed his model despite knowingly lacking firm foundations for understanding opacity and energy generation in the stellar interior. However, his results allowed for calculation of temperature, density
Density
The mass density or density of a material is defined as its mass per unit volume. The symbol most often used for density is ρ . In some cases , density is also defined as its weight per unit volume; although, this quantity is more properly called specific weight...

 and pressure
Pressure
Pressure is the force per unit area applied in a direction perpendicular to the surface of an object. Gauge pressure is the pressure relative to the local atmospheric or ambient pressure.- Definition :...

 at all points inside a star, and Eddington argued that his theory was so useful for further astrophysical investigation that it should be retained despite not being based on completely accepted physics. James Jeans contributed the important suggestion that stellar matter would certainly be ionized
Ionization
Ionization is the process of converting an atom or molecule into an ion by adding or removing charged particles such as electrons or other ions. This is often confused with dissociation. A substance may dissociate without necessarily producing ions. As an example, the molecules of table sugar...

, but that was the end of any collaboration between the pair, who became famous for their lively debates.

Eddington defended his method by pointing to the utility of his results, particularly his important mass-luminosity relation. This had the unexpected result of showing that virtually all stars, including giants and dwarfs, behaved as ideal gases. In the process of developing his stellar models, he sought to overturn current thinking about the sources of stellar energy. Jeans and others defended the Kelvin–Helmholtz mechanism, which was based on classical mechanics, while Eddington speculated broadly about the qualitative and quantitative consequences of possible proton-electron annihilation and nuclear fusion processes.

With these assumptions, he demonstrated that the interior temperature of stars must be millions of degrees. In 1924, he discovered the mass-luminosity relation
Main sequence
The main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Hertzsprung and Henry Norris Russell...

 for star
Star
A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...

s (see Lecchini in #External links and references ). Despite some disagreement, Eddington's models were eventually accepted as a powerful tool for further investigation, particularly in issues of stellar evolution. The confirmation of his estimated stellar diameters by Michelson in 1920 proved crucial in convincing astronomers unused to Eddington's intuitive, exploratory style. Eddington's theory appeared in mature form in 1926 as The Internal Constitution of the Stars, which became an important text for training an entire generation of astrophysicists.

During World War I Eddington became embroiled in controversy within the British astronomical and scientific communities. Many astronomers, chief among them H.H. Turner, argued that scientific relations with all of the Central Powers should be permanently ended due to their conduct in the war. Eddington, a Quaker pacifist, struggled to keep wartime bitterness out of astronomy. He repeatedly called for British scientists to preserve their pre-war friendships and collegiality with German scientists. Eddington's pacifism caused severe difficulties during the war, especially when he was called up for conscription in 1918. He claimed conscientious objector
Conscientious objector
A conscientious objector is an "individual who has claimed the right to refuse to perform military service" on the grounds of freedom of thought, conscience, and/or religion....

 status, a position recognized by the law, if somewhat despised by the public. In 1918 the government sought to revoke this deferment, and only the timely intervention of the Astronomer Royal and other high profile figures kept Eddington out of prison.

Eddington's work in astrophysics in the late 1920s and the 1930s continued his work in stellar structure, and precipitated further clashes with Jeans and Edward Arthur Milne. An important topic was the extension of his models to take advantage of developments in quantum physics, including the use of degeneracy physics in describing dwarf stars. This precipitated his famous dispute with Subrahmanyan Chandrasekhar
Subrahmanyan Chandrasekhar
Subrahmanyan Chandrasekhar, FRS ) was an Indian origin American astrophysicist who, with William A. Fowler, won the 1983 Nobel Prize for Physics for key discoveries that led to the currently accepted theory on the later evolutionary stages of massive stars...

, who was then a student at Cambridge. Chandrasekhar's work presaged the existence of black hole
Black hole
A black hole is a region of spacetime from which nothing, not even light, can escape. The theory of general relativity predicts that a sufficiently compact mass will deform spacetime to form a black hole. Around a black hole there is a mathematically defined surface called an event horizon that...

s, which at the time seemed so absurdly non-physical that Eddington refused to believe that Chandrasekhar's purely mathematical derivation had consequences for the real world. Chandrasekhar's narrative of this incident, in which his work is harshly rejected, portrays Eddington as rather cruel and dogmatic, and is at variance with Eddington's character as described by other contemporaries. Eddington's criticism seems to have been based on a suspicion that a purely mathematical derivation from quantum theory was not enough to explain the daunting physical paradoxes that were apparently part of degenerate stars.

Relativity


During World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

 Eddington was Secretary of the Royal Astronomical Society
Royal Astronomical Society
The Royal Astronomical Society is a learned society that began as the Astronomical Society of London in 1820 to support astronomical research . It became the Royal Astronomical Society in 1831 on receiving its Royal Charter from William IV...

, which meant he was the first to receive a series of letters and papers from Willem de Sitter
Willem de Sitter
Willem de Sitter was a Dutch mathematician, physicist and astronomer.-Life and work:Born in Sneek, De Sitter studied mathematics at the University of Groningen and then joined the Groningen astronomical laboratory. He worked at the Cape Observatory in South Africa...

 regarding Einstein’s theory of general relativity. Eddington was fortunate in being not only one of the few astronomers with the mathematical skills to understand general relativity, but (owing to his internationalist and pacifist views) one of the few at the time who was still interested in pursuing a theory developed by a German physicist. He quickly became the chief supporter and expositor of relativity in Britain. He and Astronomer Royal Frank Watson Dyson
Frank Watson Dyson
Sir Frank Watson Dyson, KBE, FRS was an English astronomer and Astronomer Royal who is remembered today largely for introducing time signals from Greenwich, England, and for the role he played in testing Einstein's theory of general relativity.- Biography :Dyson was born in Measham, near...

 organized two expeditions to observe a solar eclipse in 1919 to make the first empirical test of Einstein
Albert Einstein
Albert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...

’s theory: the measurement of the deflection of light by the sun's gravitational field. In fact, it was Dyson’s argument for the indispensability of Eddington’s expertise in this test that allowed him to escape prison during the war.


After the war, Eddington travelled to the island of Príncipe
Príncipe
Príncipe is the northern and smaller of the two major islands of the country of São Tomé and Príncipe lying off the west coast of Africa. It has an area of 136 km² and a population of approximately 5,000. The island is a heavily eroded volcano over three million years old, surrounded by other...

 near Africa to watch the solar eclipse of 29 May 1919
Solar eclipse of May 29, 1919
A total solar eclipse occurred on May 29, 1919. With a maximum duration of totality of 6 minutes 51 seconds, it was one of the longest solar eclipses of the 20th century. It was visible throughout most of South America and Africa as a partial eclipse...

. During the eclipse, he took pictures of the stars in the region around the Sun. According to the theory of general relativity
General relativity
General relativity or the general theory of relativity is the geometric theory of gravitation published by Albert Einstein in 1916. It is the current description of gravitation in modern physics...

, stars with light rays that passed near the Sun would appear to have been slightly shifted because their light had been curved by its gravitational field. This effect is noticeable only during eclipses, since otherwise the Sun's brightness obscures the affected stars. Eddington showed that Newtonian gravitation could be interpreted to predict half the shift predicted by Einstein. (Somewhat confusingly, this same half-shift was initially predicted by Einstein with an incomplete version of general relativity. By the time of the 1919 eclipse Einstein had corrected his calculations.)

Eddington's observations published the next year confirmed Einstein's theory, and were hailed at the time as a conclusive proof of general relativity over the Newtonian model. The news was reported in newspapers all over the world as a major story. Afterward, Eddington embarked on a campaign to popularize relativity and the expedition as landmarks both in scientific development and international scientific relations.

It has been claimed that Eddington's observations were of poor quality and he had unjustly discounted simultaneous observations at Sobral, Brazil which appeared closer to the Newtonian model. The quality of the 1919 results was indeed poor compared to later observations, but was sufficient to persuade contemporary astronomers. The rejection of the results from the Brazil expedition was due to a defect in the telescopes used which, again, was completely accepted and well-understood by contemporary astronomers.

Throughout this period Eddington lectured on relativity, and was particularly well known for his ability to explain the concepts in lay terms as well as scientific. He collected many of these into the Mathematical Theory of Relativity in 1923, which Albert Einstein
Albert Einstein
Albert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...

 suggested was "the finest presentation of the subject in any language." He was an early advocate of Einstein's General Relativity, and an interesting anecdote well illustrates his humour and personal intellectual investment: Ludwig Silberstein, a physicist who thought of himself as an expert on relativity, approached Eddington at the Royal Society
Royal Society
The Royal Society of London for Improving Natural Knowledge, known simply as the Royal Society, is a learned society for science, and is possibly the oldest such society in existence. Founded in November 1660, it was granted a Royal Charter by King Charles II as the "Royal Society of London"...

's (6 November) 1919 meeting where he had defended Einstein's Relativity with his Brazil-Principe Solar Eclipse calculations with some degree of scepticism and ruefully charged Arthur as one who claimed to be one of three men who actually understood the theory (Silberstein, of course, was including himself and Einstein as the other two). When Eddington refrained from replying, he insisted Arthur not be "so shy", whereupon Eddington replied, "Oh, no! I was wondering who the third one might be!"

Popular and philosophical writings


Eddington wrote a clever parody of the classic poem The Rubaiyat of Omar Khayyam recounting his 1919 solar eclipse experiment, including the verse:
Oh leave the Wise our measures to collate

One thing at least is certain, LIGHT has WEIGHT

One thing is certain, and the rest debate -

Light-rays, when near the Sun, DO NOT GO STRAIGHT.


During the 1920s and 30s Eddington gave innumerable lectures, interviews, and radio broadcasts on relativity (in addition to his textbook The Mathematical Theory of Relativity), and later, quantum mechanics. Many of these were gathered into books, including The Nature of the Physical World and New Pathways in Science. His skillful use of literary allusions and humor helped make these famously difficult subjects quite accessible.

Eddington's books and lectures were immensely popular with the public, not only because of Eddington’s clear and entertaining exposition, but also for his willingness to discuss the philosophical and religious implications of the new physics. He argued for a deeply-rooted philosophical harmony between scientific investigation and religious mysticism, and also that the positivist nature of modern physics (i.e., relativity and quantum physics) provided new room for personal religious experience and free will. Unlike many other spiritual scientists, he rejected the idea that science could provide proof of religious propositions. He promoted the infinite monkey theorem
Infinite monkey theorem
The infinite monkey theorem states that a monkey hitting keys at random on a typewriter keyboard for an infinite amount of time will almost surely type a given text, such as the complete works of William Shakespeare....

 in his 1928 book The Nature of the Physical World, with the phrase "If an army of monkeys were strumming on typewriters, they might write all the books in the British Museum
British Museum
The British Museum is a museum of human history and culture in London. Its collections, which number more than seven million objects, are amongst the largest and most comprehensive in the world and originate from all continents, illustrating and documenting the story of human culture from its...

". His popular writings made him, quite literally, a household name in Great Britain between the world wars.

Idealism


Sir Arthur Eddington wrote in his book The Nature of the Physical World that “The stuff of the world is mind-stuff.”
The idealist conclusion was not integral to his epistemology but was based on two main arguments.

The first derives directly from current physical theory. Briefly, mechanical theories of the ether and of the behavior of fundamental particles have been discarded in both relativity and quantum physics. From this Eddington inferred that a materialistic metaphysics was outmoded and that, in consequence—the disjunction of materialism or idealism being assumed exhaustive—an idealistic metaphysics is required. The second and more interesting argument was based on Eddington's epistemology and may be regarded as consisting of two parts. First, all we know of the objective world is its structure, and the structure of the objective world is precisely mirrored in our own consciousness. We therefore have no reason to doubt that the objective world, too, is "mind-stuff." Dualistic metaphysics, then, cannot be evidentially supported. (The conclusion appears to be a valid deduction from its premises.)

But, second, not only can we not know that the objective world is nonmentalistic, we also cannot intelligibly suppose that it could be material. To conceive of a dualism entails attributing material properties to the objective world. However, this presupposes that we could observe that the objective world has material properties. But this is absurd, for whatever is observed must ultimately be the content of our own consciousness and, consequently, nonmaterial.

Ian Barbour
Ian Barbour
Ian Graeme Barbour, born 5 October 1923, is an American scholar on the relationship between science and religion. According to the Public Broadcasting Service his mid-1960s Issues in Science and Religion "has been credited with literally creating the contemporary field of science and religion."In...

 in his book Issues in Science and Religion (1966), p. 133, cites Arthur Eddington's The Nature of the Physical World (1928) for a text that argues The Heisenberg Uncertainty Principles provides a scientific basis for "the defense of the idea of human freedom" and his Science and the Unseen World (1929) for support of philosophical idealism "the thesis that reality is basically mental".

Charles De Koninck
Charles De Koninck
Charles De Koninck was a Belgian-Canadian Thomist philosopher and theologian. As director of the Department of Philosophy at the Université Laval in Quebec, he had decisive influence on catholic philosophy in French Canada and also influenced Catholic philosophers in English Canada and the United...

 points out that Eddington believed in objective reality existing apart from our minds, but was using the phrase "mind-stuff" to highlight the inherent intelligibility of the world: that our minds and the physical world are made of the same "stuff" and that our minds are the inescapable connection to the world. As De Koninck quotes Eddington,

Indeterminism



Against Albert Einstein
Albert Einstein
Albert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...

 and others who advocated determinism
Determinism
Determinism is the general philosophical thesis that states that for everything that happens there are conditions such that, given them, nothing else could happen. There are many versions of this thesis. Each of them rests upon various alleged connections, and interdependencies of things and...

, indeterminism—championed by Eddington—says that a physical object has an ontologically
Ontology
Ontology is the philosophical study of the nature of being, existence or reality as such, as well as the basic categories of being and their relations...

 undetermined component that is not due to the epistemological limitations of physicists' understanding. The Uncertainty Principle
Uncertainty principle
In quantum mechanics, the Heisenberg uncertainty principle states a fundamental limit on the accuracy with which certain pairs of physical properties of a particle, such as position and momentum, can be simultaneously known...

 in quantum mechanics
Quantum mechanics
Quantum mechanics, also known as quantum physics or quantum theory, is a branch of physics providing a mathematical description of much of the dual particle-like and wave-like behavior and interactions of energy and matter. It departs from classical mechanics primarily at the atomic and subatomic...

, then, would not necessarily be due to hidden variables
Hidden variable theory
Historically, in physics, hidden variable theories were espoused by some physicists who argued that quantum mechanics is incomplete. These theories argue against the orthodox interpretation of quantum mechanics, which is the Copenhagen Interpretation...

 but to an indeterminism in nature itself.

Cosmology


Eddington was also heavily involved with the development of the first generation of general relativistic cosmological models. He had been investigating the instability of the Einstein universe when he learned of both Lemaitre's
Georges Lemaître
Monsignor Georges Henri Joseph Édouard Lemaître was a Belgian priest, astronomer and professor of physics at the Catholic University of Louvain. He was the first person to propose the theory of the expansion of the Universe, widely misattributed to Edwin Hubble...

 1927 paper postulating an expanding or contracting universe and Hubble's work on the recession on the spiral nebulae. He felt the cosmological constant
Cosmological constant
In physical cosmology, the cosmological constant was proposed by Albert Einstein as a modification of his original theory of general relativity to achieve a stationary universe...

 must have played the crucial role in the universe's evolution from an Einsteinian steady state to its current expanding state, and most of his cosmological investigations focused on the constant's significance and characteristics.

Fundamental theory


During the 1920s until his death, he increasingly concentrated on what he called "fundamental theory
Theory of everything
A theory of everything is a putative theory of theoretical physics that fully explains and links together all known physical phenomena, and predicts the outcome of any experiment that could be carried out in principle....

" which was intended to be a unification of quantum theory
Quantum mechanics
Quantum mechanics, also known as quantum physics or quantum theory, is a branch of physics providing a mathematical description of much of the dual particle-like and wave-like behavior and interactions of energy and matter. It departs from classical mechanics primarily at the atomic and subatomic...

, relativity
Theory of relativity
The theory of relativity, or simply relativity, encompasses two theories of Albert Einstein: special relativity and general relativity. However, the word relativity is sometimes used in reference to Galilean invariance....

 and gravitation
Gravitation
Gravitation, or gravity, is a natural phenomenon by which physical bodies attract with a force proportional to their mass. Gravitation is most familiar as the agent that gives weight to objects with mass and causes them to fall to the ground when dropped...

. At first he progressed along "traditional" lines, but turned increasingly to an almost numerological
Numerology
Numerology is any study of the purported mystical relationship between a count or measurement and life. It has many systems and traditions and beliefs...

 analysis of the dimensionless ratios of fundamental constants.

His basic approach was to combine several fundamental constants in order to produce a dimensionless number. In many cases these would result in numbers close to 1040, its square, or its square root. He was convinced that the mass of the proton
Proton
The proton is a subatomic particle with the symbol or and a positive electric charge of 1 elementary charge. One or more protons are present in the nucleus of each atom, along with neutrons. The number of protons in each atom is its atomic number....

 and the charge of the electron
Electron
The electron is a subatomic particle with a negative elementary electric charge. It has no known components or substructure; in other words, it is generally thought to be an elementary particle. An electron has a mass that is approximately 1/1836 that of the proton...

 were a natural and complete specification for constructing a Universe and that their values were not accidental. One of the discoverers of quantum mechanics, Paul Dirac
Paul Dirac
Paul Adrien Maurice Dirac, OM, FRS was an English theoretical physicist who made fundamental contributions to the early development of both quantum mechanics and quantum electrodynamics...

, also pursued this line of investigation, which has become known as the Dirac large numbers hypothesis
Dirac large numbers hypothesis
The Dirac large numbers hypothesis is an observation made by Paul Dirac in 1937 relating ratios of size scales in the Universe to that of force scales. The ratios constitute very large, dimensionless numbers: some 40 orders of magnitude in the present cosmological epoch...

, and some scientists even today believe it has something to it.

A somewhat damaging statement in his defence of these concepts involved the fine structure constant, α. At the time it was measured to be very close to 1/136, and he argued that the value should in fact be exactly 1/136 for epistemological reasons. Later measurements placed the value much closer to 1/137, at which point he switched his line of reasoning to argue that one more should be added to the degrees of freedom
Degrees of freedom (physics and chemistry)
A degree of freedom is an independent physical parameter, often called a dimension, in the formal description of the state of a physical system...

, so that the value should in fact be exactly 1/137, the Eddington number
Eddington number
In astrophysics, the Eddington number, NEdd, is the number of protons in the observable universe. The name honors the British astrophysicist Arthur Eddington who, in 1938, was the first to propose a calculation of NEdd, and to explain why this number could be important for cosmology and the...

. Wags at the time started calling him "Arthur Adding-one". The current measured value is estimated at 1/137.035999679(94).

Eddington believed he had identified an algebraic basis for fundamental physics, which he termed "E-frames" (representing a certain group
Group (mathematics)
In mathematics, a group is an algebraic structure consisting of a set together with an operation that combines any two of its elements to form a third element. To qualify as a group, the set and the operation must satisfy a few conditions called group axioms, namely closure, associativity, identity...

 – a Clifford algebra). While his theory has long been neglected by the general physics community, similar algebraic notions underlie many modern attempts at a grand unified theory. Moreover, Eddington's emphasis on the values of the fundamental constants, and specifically upon dimensionless numbers derived from them, is nowadays a central concern of physics.

He did not complete this line of research before his death in 1944, and his book entitled Fundamental Theory was published posthumously in 1948. Eddington died in Cambridge
Cambridge
The city of Cambridge is a university town and the administrative centre of the county of Cambridgeshire, England. It lies in East Anglia about north of London. Cambridge is at the heart of the high-technology centre known as Silicon Fen – a play on Silicon Valley and the fens surrounding the...

, England and is buried at the Parish of the Ascension Burial Ground
Ascension Parish Burial Ground, Cambridge
The Ascension Parish Burial Ground, formerly St Giles and St Peter's Parish, is a cemetery just off Huntingdon Road near the junction with Storey's Way in the northwest of Cambridge, England. It includes the graves of many Cambridge academics and non-conformists of the 19th and early 20th century...

 in Cambridge.

Eddington number (cycling)


Eddington is credited with devising a measure of a cyclist's long distance riding achievements. The Eddington Number in this context is defined as E, the number of days a cyclist has cycled more than E miles. For example an Eddington Number of 70 would imply that a cyclist has cycled more than 70 miles in a day on 70 occasions. Achieving a high Eddington number is difficult since moving from, say, 70 to 75 will probably require more than five new long distance rides since any rides shorter than 75 miles will no longer be included in the reckoning.

The construct of the Eddington Number for cycling is identical to the h-index
H-index
The h-index is an index that attempts to measure both the productivity and impact of the published work of a scientist or scholar. The index is based on the set of the scientist's most cited papers and the number of citations that they have received in other publications...

 that quantifies both the actual scientific productivity and the apparent scientific impact of a scientist.

Honours


Awards
  • Smith's Prize
    Smith's Prize
    The Smith's Prize was the name of each of two prizes awarded annually to two research students in theoretical Physics, mathematics and applied mathematics at the University of Cambridge, Cambridge, England.- History :...

     (1907)
  • Bruce Medal
    Bruce Medal
    The Catherine Wolfe Bruce Gold Medal is awarded every year by the Astronomical Society of the Pacific for outstanding lifetime contributions to astronomy. It is named after Catherine Wolfe Bruce, an American patroness of astronomy, and was first awarded in 1898...

     of Astronomical Society of the Pacific (1924)
  • Henry Draper Medal
    Henry Draper Medal
    The Henry Draper Medal is awarded by the United States National Academy of Sciences "for investigations in astronomical physics". Named after Henry Draper, the medal is awarded with a gift of USD $15,000...

     of the National Academy of Sciences
    United States National Academy of Sciences
    The National Academy of Sciences is a corporation in the United States whose members serve pro bono as "advisers to the nation on science, engineering, and medicine." As a national academy, new members of the organization are elected annually by current members, based on their distinguished and...

     (1924)
  • Gold Medal of the Royal Astronomical Society
    Gold Medal of the Royal Astronomical Society
    -History:In the early years, more than one medal was often awarded in a year, but by 1833 only one medal was being awarded per year. This caused a problem when Neptune was discovered in 1846, because many felt an award should jointly be made to John Couch Adams and Urbain Le Verrier...

     (1924)
  • Prix Jules Janssen
    Prix Jules Janssen
    The Prix Jules Janssen is the highest award of the French Astronomical Society. Created in 1897 and awarded annually, it is usually given in alternate years to a French astronomer, and to an astronomer of another nationality. It is distinct from the Janssen Medal , which is awarded by the French...

     of the French Astronomical Society (1928)
  • Royal Medal
    Royal Medal
    The Royal Medal, also known as The Queen's Medal, is a silver-gilt medal awarded each year by the Royal Society, two for "the most important contributions to the advancement of natural knowledge" and one for "distinguished contributions in the applied sciences" made within the Commonwealth of...

     of the Royal Society
    Royal Society
    The Royal Society of London for Improving Natural Knowledge, known simply as the Royal Society, is a learned society for science, and is possibly the oldest such society in existence. Founded in November 1660, it was granted a Royal Charter by King Charles II as the "Royal Society of London"...

     (1928)
  • Knighthood (1930)
  • Order of Merit (1938)
  • Hon. Freeman of Kendal
    Kendal
    Kendal, anciently known as Kirkby in Kendal or Kirkby Kendal, is a market town and civil parish within the South Lakeland District of Cumbria, England...

    , 1930

Named after him
  • Lunar crater Eddington
    Eddington (crater)
    Eddington is the lava-flooded remnant of a lunar impact crater, located on the western part of Oceanus Procellarum. The western rim is attached to the wall of the walled plain Struve. To the east-southeast is the smaller but prominent crater Seleucus...

  • asteroid
    Asteroid
    Asteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones...

     2761 Eddington
    2761 Eddington
    2761 Eddington is a main-belt asteroid discovered on January 1, 1981 by Bowell, E. at Flagstaff .- External links :*...

  • Royal Astronomical Society
    Royal Astronomical Society
    The Royal Astronomical Society is a learned society that began as the Astronomical Society of London in 1820 to support astronomical research . It became the Royal Astronomical Society in 1831 on receiving its Royal Charter from William IV...

    's Eddington Medal
    Eddington Medal
    The Eddington Medal, named after Sir Arthur Eddington, is awarded by the Royal Astronomical Society nominally once every two years for investigations of outstanding merit in theoretical astrophysics.- Recipients :* 1953 Georges Lemaître...

  • Eddington mission
    Eddington mission
    The Eddington mission was a European Space Agency project that planned to search for Earth-like planets. It was named for Arthur Eddington, a noted physicist who translated Einstein's work. It was originally planned for operation in 2008, but was delayed...

    , now cancelled
  • Eddington Tower, halls of residence at the University of Essex
    University of Essex
    The University of Essex is a British campus university whose original and largest campus is near the town of Colchester, England. Established in 1963 and receiving its Royal Charter in 1965...

  • Eddington Astronomical Society, an amateur society based in his hometown of Kendal
    Kendal
    Kendal, anciently known as Kirkby in Kendal or Kirkby Kendal, is a market town and civil parish within the South Lakeland District of Cumbria, England...

  • Eddington, a house (group of students, used for in-school sports matches) of Kirkbie Kendal School
    Kirkbie Kendal School
    Kirkbie Kendal School is a comprehensive school and known as a Business and Enterprise College in Kendal, Cumbria, England, and serves the area around the town and rural countryside. Kirkbie Kendal School operates as a Foundation school, and has been regularly oversubscribed, accepting students...

    .

Service
  • Gave the Swarthmore Lecture
    Swarthmore Lecture
    Swarthmore Lecture is one of a series of lectures, started in 1908, addressed to Britain Yearly Meeting of the Religious Society of Friends .The preface to the very first lecture explains the purpose of the series....

     in 1929.
  • Chairman of the National Peace Council
    National Peace Council
    The National Peace Council, founded in 1908, and disbanded in 2000, acted as the co-ordinating body for almost 200 groups across Britain, with a membership ranging from small village peace groups to national trade unions and local authorities...

     1941–1943.
  • President of the International Astronomical Union
    International Astronomical Union
    The International Astronomical Union IAU is a collection of professional astronomers, at the Ph.D. level and beyond, active in professional research and education in astronomy...

    ; of the Physical Society
    Physical Society of London
    The Physical Society of London, England, existed from 1874 to 1921. It was a scientific society and produced the Proceedings of the Physical Society of London...

    , 1930–32; of the Royal Astronomical Society, 1921–23
  • Romanes Lecture
    Romanes Lecture
    The Romanes Lecture is a prestigious free public lecture given annually at the Sheldonian Theatre, Oxford, England.The lecture series was founded by, and named after, the biologist George Romanes, and has been running since 1892. Over the years, many notable figures from the Arts and Sciences have...

    r, 1922
  • Gifford Lecturer
    Gifford Lectures
    The Gifford Lectures were established by the will of Adam Lord Gifford . They were established to "promote and diffuse the study of Natural Theology in the widest sense of the term — in other words, the knowledge of God." The term natural theology as used by Gifford means theology supported...

    , 1927

In popular culture


Eddington was portrayed by actor David Tennant
David Tennant
David Tennant is a Scottish actor. In addition to his work in theatre, including a widely praised Hamlet, Tennant is best known for his role as the tenth incarnation of the Doctor in Doctor Who, along with the title role in the 2005 TV serial Casanova and as Barty Crouch, Jr...

 in the television film Einstein and Eddington
Einstein and Eddington
Einstein and Eddington is a British single drama produced by Company Pictures and the BBC, in association with HBO. It featured David Tennant as British scientist Sir Arthur Stanley Eddington, and Andy Serkis as Albert Einstein...

(duration 89 minutes), a co-production of the BBC
BBC
The British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff...

 and HBO, broadcast in the UK on Saturday 22 November 2008, on BBC2. The film touched on Eddington's rumored repressed homosexuality.

Arthur Eddington is a primary focus in the short story "The Mathematician's Nightmare: The Vision of Professor Squarepunt" by Bertrand Russell
Bertrand Russell
Bertrand Arthur William Russell, 3rd Earl Russell, OM, FRS was a British philosopher, logician, mathematician, historian, and social critic. At various points in his life he considered himself a liberal, a socialist, and a pacifist, but he also admitted that he had never been any of these things...

, a work featured in The Mathematical Magpie
The Mathematical Magpie
The Mathematical Magpie is an anthology published in 1962, compiled by Clifton Fadiman as a companion volume to his Fantasia Mathematica . The volume contains stories, cartoons, essays, rhymes, music, anecdotes, aphorisms, and other oddments. Authors include Arthur Clarke, Isaac Asimov, Mark Twain,...

 by Clifton Fadiman
Clifton Fadiman
Clifton P. "Kip" Fadiman was an American intellectual, author, editor, radio and television personality.-Literary career:...

.

See also

  • Astronomy
    Astronomy
    Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...

    : Eddington limit, Chandrasekhar limit
    Chandrasekhar limit
    When a star starts running out of fuel, it usually cools off and collapses into one of three compact forms, depending on its total mass:* a White Dwarf, a big lump of Carbon and Oxygen atoms, almost like one huge molecule...

    , Gravitational lens
    Gravitational lens
    A gravitational lens refers to a distribution of matter between a distant source and an observer, that is capable of bending the light from the source, as it travels towards the observer...

    , Stellar nucleosynthesis
    Stellar nucleosynthesis
    Stellar nucleosynthesis is the collective term for the nuclear reactions taking place in stars to build the nuclei of the elements heavier than hydrogen. Some small quantity of these reactions also occur on the stellar surface under various circumstances...

    , Timeline of stellar astronomy
    Timeline of stellar astronomy
    Timeline of stellar astronomy* 134 BC — Hipparchus creates the magnitude scale of stellar apparent luminosities* 185 AD — Chinese astronomers become the first to observe a supernova, the SN 185...

    , Astronomers, Astrophysicists
  • Science
    Science
    Science is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe...

    : Pathological science
    Pathological science
    Pathological science is the process in science in which "people are tricked into false results ... by subjective effects, wishful thinking or threshold interactions". The term was first used by Irving Langmuir, Nobel Prize-winning chemist, during a 1953 colloquium at the Knolls Research Laboratory...

    , Fundamental physical constant, Timeline of gravitational physics and relativity
    Timeline of gravitational physics and relativity
    Timeline of gravitational physics and general relativity* 3rd century BC - Aristarchus of Samos proposes heliocentric model, measures the distance to the moon and its size...

    , General relativity
    General relativity
    General relativity or the general theory of relativity is the geometric theory of gravitation published by Albert Einstein in 1916. It is the current description of gravitation in modern physics...

    , Special relativity
    Special relativity
    Special relativity is the physical theory of measurement in an inertial frame of reference proposed in 1905 by Albert Einstein in the paper "On the Electrodynamics of Moving Bodies".It generalizes Galileo's...

    , Luminiferous aether
    Luminiferous aether
    In the late 19th century, luminiferous aether or ether, meaning light-bearing aether, was the term used to describe a medium for the propagation of light....

    , Experiments, Fundamental theory, Eddington number
    Eddington number
    In astrophysics, the Eddington number, NEdd, is the number of protons in the observable universe. The name honors the British astrophysicist Arthur Eddington who, in 1938, was the first to propose a calculation of NEdd, and to explain why this number could be important for cosmology and the...

    , Eddington–Dirac number, Time's arrow
    Time's arrow
    Time's Arrow may refer to:*Time's Arrow , by Martin Amis*"Time's Arrow" , a short story by Arthur C. Clarke*"Time's Arrow" , a two-part episode of Star Trek: The Next Generation-See also:...

    , Basic concepts of quantum mechanics
    Basic concepts of quantum mechanics
    Quantum mechanics explains the behaviour of matter and energy on the scale of atoms and subatomic particles.Classical physics explains matter and energy at the macroscopic level of the scale familiar to human experience, including the behavior of astronomical bodies...

    .
  • Organizations: Trinity College, Cambridge
    Trinity College, Cambridge
    Trinity College is a constituent college of the University of Cambridge. Trinity has more members than any other college in Cambridge or Oxford, with around 700 undergraduates, 430 graduates, and over 170 Fellows...

    , Religious Society of Friends
    Religious Society of Friends
    The Religious Society of Friends, or Friends Church, is a Christian movement which stresses the doctrine of the priesthood of all believers. Members are known as Friends, or popularly as Quakers. It is made of independent organisations, which have split from one another due to doctrinal differences...

    , Royal Astronomical Society
    Royal Astronomical Society
    The Royal Astronomical Society is a learned society that began as the Astronomical Society of London in 1820 to support astronomical research . It became the Royal Astronomical Society in 1831 on receiving its Royal Charter from William IV...

  • Other: Georges Lemaître
    Georges Lemaître
    Monsignor Georges Henri Joseph Édouard Lemaître was a Belgian priest, astronomer and professor of physics at the Catholic University of Louvain. He was the first person to propose the theory of the expansion of the Universe, widely misattributed to Edwin Hubble...

    , Infinite monkey theorem
    Infinite monkey theorem
    The infinite monkey theorem states that a monkey hitting keys at random on a typewriter keyboard for an infinite amount of time will almost surely type a given text, such as the complete works of William Shakespeare....

    , One hundred thirty-seven, Numerology
    Numerology
    Numerology is any study of the purported mystical relationship between a count or measurement and life. It has many systems and traditions and beliefs...

    , Eddington (disambiguation), List of English people, List of astronomical topics
  • List of science and religion scholars

External links and references



Obituaries

  • Obituary by Henry Norris Russell, Astrophysical Journal
    Astrophysical Journal
    The Astrophysical Journal is a peer-reviewed scientific journal covering astronomy and astrophysics. It was founded in 1895 by the American astronomers George Ellery Hale and James Edward Keeler. It publishes three 500-page issues per month....

    101 (1943–46) 133
  • Obituary by A. Vibert Douglas, Journal of the Royal Astronomical Society of Canada
    Journal of the Royal Astronomical Society of Canada
    The Journal of the Royal Astronomical Society of Canada is a bimonthly peer reviewed scientific journal published by the Royal Astronomical Society of Canada since 1907. The title in French is Journal de la Société royale d'astronomie du Canada. The founding editor was Clarence Chant...

    ,
    39 (1943–46) 1
  • Obituary by H. Spencer Jones and E.T. Whitaker, Monthly Notices of the Royal Astronomical Society
    Monthly Notices of the Royal Astronomical Society
    Monthly Notices of the Royal Astronomical Society is one of the world's leading scientific journals in astronomy and astrophysics. It has been in continuous existence since 1827 and publishes peer-reviewed letters and papers reporting original research in relevant fields...

    105 (1943–46) 68
  • Obituary by Herbert Dingle, The Observatory 66 (1943–46) 1
  • The Times
    The Times
    The Times is a British daily national newspaper, first published in London in 1785 under the title The Daily Universal Register . The Times and its sister paper The Sunday Times are published by Times Newspapers Limited, a subsidiary since 1981 of News International...

    , Thursday, 23 November 1944; pg. 7; Issue 49998; col D: Obituary (unsigned) – Image of cutting available at MacTutor History of Mathematics archive (St. Andrews University) Website