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81-430: Since 1953, The Astrophysical Journal Supplement Series ( ApJS ) has been published in conjunction with The Astrophysical Journal , with generally longer articles to supplement the material in the journal. It publishes six volumes per year, with two 280-page issues per volume. The Astrophysical Journal Letters ( ApJL ), established in 1967 by Subrahmanyan Chandrasekhar as Part 2 of The Astrophysical Journal ,

162-533: A Google Doodle in 28 countries honouring Chandrasekhar's 107th birthday and the Chandrasekhar limit . In 2010, on account of Chandra's 100th birthday, University of Chicago conducted a symposium titled Chandrasekhar Centennial Symposium 2010 which was attended by leading astrophysicists such as Roger Penrose , Kip Thorne , Freeman Dyson , Jayant V. Narlikar , Rashid Sunyaev , G. Srinivasan , and Clifford Will . Its research talks were published in 2011 as

243-542: A Tamil family, to Sita Balakrishnan (1891–1931) and Chandrasekhara Subrahmanya Ayyar (1885–1960) who was stationed in Lahore as Deputy Auditor General of the Northwestern Railways at the time of Chandrasekhar's birth. He had two elder sisters, Rajalakshmi and Balaparvathi, three younger brothers, Vishwanathan, Balakrishnan, and Ramanathan, and four younger sisters, Sarada, Vidya, Savitri, and Sundari. His paternal uncle

324-608: A heart attack at the University of Chicago Hospital in 1995, having survived a prior heart attack in 1975. He was survived by his wife, who died on 2 September 2013 at the age of 102. She was a serious student of literature and western classical music. Once when involved in a discussion about the Bhagavad Gita , Chandrasekhar said: "I should like to preface my remarks with a personal statement in order that my later remarks will not be misunderstood. I consider myself an atheist". This

405-527: A polarization smaller than 0.3, making the large asphericity theory unlikely. Stars sufficiently massive to pass the Chandrasekhar limit provided by electron degeneracy pressure do not become white dwarf stars. Instead they explode as supernovae . If the final mass is below the Tolman–Oppenheimer–Volkoff limit , then neutron degeneracy pressure contributes to the balance against gravity and

486-476: A uniform density star in 1929. Eric G. Blackman wrote that the roles of Stoner and Anderson in the discovery of mass limits were overlooked when Freeman Dyson wrote a biography of Chandrasekhar. Michael Nauenberg claims that Stoner established the mass limit first. The priority dispute has also been discussed at length by Virginia Trimble who writes that: "Chandrasekhar famously, perhaps even notoriously did his critical calculation on board ship in 1930, and ...

567-479: A Fermi gas, and was then able to treat the mass–radius relationship in a fully relativistic manner, giving a limiting mass of approximately 2.19 × 10  kg (for μ e = 2.5 ). Stoner went on to derive the pressure – density equation of state, which he published in 1932. These equations of state were also previously published by the Soviet physicist Yakov Frenkel in 1928, together with some other remarks on

648-507: A Nobel prize "for his theoretical studies of the physical processes of importance to the structure and evolution of the stars" with William Alfred Fowler . The core of a star is kept from collapsing by the heat generated by the fusion of nuclei of lighter elements into heavier ones. At various stages of stellar evolution , the nuclei required for this process are exhausted, and the core collapses, causing it to become denser and hotter. A critical situation arises when iron accumulates in

729-610: A book titled Fluid flows to Black Holes: A tribute to S Chandrasekhar on his birth centenary . Chandrasekhar published around 380 papers in his lifetime. He wrote his first paper in 1928 when he was still an undergraduate student about Compton effect and last paper which was accepted for publication just two months before his death was in 1995 which was about non-radial oscillation of stars. The University of Chicago Press published selected papers of Chandrasekhar in seven volumes. Chandrasekhar limit The Chandrasekhar limit ( / ˌ tʃ ə n d r ə ˈ ʃ eɪ k ər / )

810-454: A bronze medal for his work on degenerate stars, in the summer of 1933, Chandrasekhar was awarded his PhD degree at Cambridge with a thesis among his four papers on rotating self-gravitating polytropes . On 9 October, he was elected to a Prize Fellowship at Trinity College for the period 1933–1937, becoming only the second Indian to receive a Trinity Fellowship after Srinivasa Ramanujan 16 years earlier. He had been so certain of failing to obtain

891-595: A centrifugal tendency allowed it to exceed the limit. Alternatively, the supernova may have resulted from the merger of two white dwarfs, so that the limit was only violated momentarily. Nevertheless, they point out that this observation poses a challenge to the use of type Ia supernovae as standard candles . Since the observation of the Champagne Supernova in 2003, several more type Ia supernovae have been observed that are very bright, and thought to have originated from white dwarfs whose masses exceeded

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972-556: A course at the University of Chicago. Two of the students who took the course, Tsung-Dao Lee and Chen-Ning Yang , won the Nobel prize before he could get one for himself. Regarding classroom interactions during his lectures, noted astrophysicist Carl Sagan stated from firsthand experience that "frivolous questions" from unprepared students were "dealt with in the manner of a summary execution", while questions of merit "were given serious attention and response". From 1952 to 1971 Chandrasekhar

1053-443: A course organised by Struve, was vetoed by the dean Henry Gale based on a racial prejudice; Hutchins said "By all means have Mr.Chandrasekhar teach". Chandrasekhar remained at the University of Chicago for his entire career. He was promoted to associate professor in 1941 and to full professor two years later at the age of 33. In 1946, when Princeton University offered Chandrasekhar a position vacated by Henry Norris Russell with

1134-401: A fellow student at Presidency College . He became a naturalised citizen of the U.S. in 1953. Many considered him as warm, positive, generous, unassuming, meticulous, and open to debate, while some others as private, intimidating, impatient and stubborn regarding non-scientific matters, and unforgiving to those who ridiculed his work. Chandrasekhar was a vegetarian . Chandrasekhar died of

1215-504: A few km radius, when gravity becomes strong enough to hold in the radiation, and the star can at last find peace. ... I think there should be a law of Nature to prevent a star from behaving in this absurd way! Eddington's proposed solution to the perceived problem was to modify relativistic mechanics so as to make the law P = K 1 ρ universally applicable, even for large ρ . Although Niels Bohr , Fowler, Wolfgang Pauli , and other physicists agreed with Chandrasekhar's analysis, at

1296-499: A galaxy approximately 4 billion light years away. According to a group of astronomers at the University of Toronto and elsewhere, the observations of this supernova are best explained by assuming that it arose from a white dwarf that had grown to twice the mass of the Sun before exploding. They believe that the star, dubbed the " Champagne Supernova " may have been spinning so fast that

1377-476: A lecture by Arnold Sommerfeld . He obtained his bachelor's degree, BSc (Hon.), in physics, in June 1930. In July 1930, Chandrasekhar was awarded a Government of India scholarship to pursue graduate studies at the University of Cambridge , where he was admitted to Trinity College , secured by R. H. Fowler with whom he communicated his first paper. During his travels to England , Chandrasekhar spent his time working out

1458-403: A naming contest which attracted 6,000 entries from fifty states and sixty-one countries. The Chandra X-ray Observatory was launched and deployed by Space Shuttle Columbia on 23 July 1999. The Chandrasekhar number , an important dimensionless number of magnetohydrodynamics , is named after him. The asteroid 1958 Chandra is also named after Chandrasekhar. The Himalayan Chandra Telescope

1539-418: A new quantity he termed " dynamical friction ", which has the dual effects of decelerating the star and helping to stabilize clusters of stars. Chandrasekhar extended this analysis to the interstellar medium, showing that clouds of galactic gas and dust are distributed very unevenly. Chandrasekhar studied at Presidency College, Madras (now Chennai ) and the University of Cambridge . A long-time professor at

1620-458: A process called stellar evolution . The next step depends upon the mass of the star. Stars below the Chandrasekhar limit become stable white dwarf stars , remaining that way throughout the rest of the history of the universe absent external forces. Stars above the limit can become neutron stars or black holes . The Chandrasekhar limit is a consequence of competition between gravity and electron degeneracy pressure. Electron degeneracy pressure

1701-554: A salary double that of Chicago's, Hutchins incremented his salary matching with that of Princeton's and persuaded Chandrasekhar to stay in Chicago. In 1952, he became Morton D. Hull Distinguished Service Professor of Theoretical Astrophysics and Enrico Fermi Institute , upon Enrico Fermi 's invitation. In 1953, he and his wife, Lalitha Chandrasekhar, took American citizenship. After the Laboratory for Astrophysics and Space Research (LASR)

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1782-411: A unique style of mastering several fields of physics and astrophysics; consequently, his working life can be divided into distinct periods. He would exhaustively study a specific area, publish several papers in it and then write a book summarizing the major concepts in the field. He would then move on to another field for the next decade and repeat the pattern. Thus he studied stellar structure , including

1863-471: Is a quantum-mechanical effect arising from the Pauli exclusion principle . Since electrons are fermions , no two electrons can be in the same state, so not all electrons can be in the minimum-energy level. Rather, electrons must occupy a band of energy levels . Compression of the electron gas increases the number of electrons in a given volume and raises the maximum energy level in the occupied band. Therefore,

1944-401: Is emitted as optical light. This process is believed responsible for supernovae of types Ib, Ic, and II . Type Ia supernovae derive their energy from runaway fusion of the nuclei in the interior of a white dwarf . This fate may befall carbon – oxygen white dwarfs that accrete matter from a companion giant star , leading to a steadily increasing mass. As the white dwarf's mass approaches

2025-772: Is measured in standard solar radii or kilometers, and mass in standard solar masses. Calculated values for the limit vary depending on the nuclear composition of the mass. Chandrasekhar gives the following expression, based on the equation of state for an ideal Fermi gas : M limit = ω 3 0 3 π 2 ( ℏ c G ) 3 2 1 ( μ e m H ) 2 {\displaystyle M_{\text{limit}}={\frac {\omega _{3}^{0}{\sqrt {3\pi }}}{2}}\left({\frac {\hbar c}{G}}\right)^{\frac {3}{2}}{\frac {1}{(\mu _{\text{e}}m_{\text{H}})^{2}}}} where: As √ ħc / G

2106-518: Is named after him. In the Biographical Memoirs of Fellows of the Royal Society of London , R. J. Tayler wrote: "Chandrasekhar was a classical applied mathematician whose research was primarily applied in astronomy and whose like will probably never be seen again." Chandrasekhar supervised 45 PhD students. After his death, his wife Lalitha Chandrasekhar made a gift of his Nobel Prize money to

2187-530: Is now a separate journal focusing on the rapid publication of high-impact astronomical research. The three journals were published by the University of Chicago Press for the American Astronomical Society until, in January 2009, publication was transferred to IOP Publishing , following the move of the society's Astronomical Journal in 2008. The reason for the changes were given by the society as

2268-541: Is the Planck mass , the limit is of the order of M Pl 3 m H 2 {\displaystyle {\frac {M_{\text{Pl}}^{3}}{m_{\text{H}}^{2}}}} The limiting mass can be obtained formally from the Chandrasekhar's white dwarf equation by taking the limit of large central density. A more accurate value of the limit than that given by this simple model requires adjusting for various factors, including electrostatic interactions between

2349-430: Is the pressure , ρ is the mass density , and K 1 is a constant. Solving the hydrostatic equation leads to a model white dwarf that is a polytrope of index ⁠ 3 / 2 ⁠ – and therefore has radius inversely proportional to the cube root of its mass, and volume inversely proportional to its mass. As the mass of a model white dwarf increases, the typical energies to which degeneracy pressure forces

2430-402: Is the mass above which electron degeneracy pressure in the star's core is insufficient to balance the star's own gravitational self-attraction. Normal stars fuse gravitationally compressed hydrogen into helium, generating vast amounts of heat. As the hydrogen is consumed, the stars' core compresses further allowing the helium and heavier nuclei to fuse ultimately resulting in stable iron nuclei,

2511-440: Is the maximum mass of a stable white dwarf star . The currently accepted value of the Chandrasekhar limit is about 1.4  M ☉ ( 2.765 × 10  kg ). The limit was named after Subrahmanyan Chandrasekhar . White dwarfs resist gravitational collapse primarily through electron degeneracy pressure , compared to main sequence stars, which resist collapse through thermal pressure . The Chandrasekhar limit

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2592-877: The Aberdeen Proving Ground in Maryland. While there, he worked on problems of ballistics , resulting in reports such as 1943's On the decay of plane shock waves , Optimum height for the bursting of a 105mm shell , On the Conditions for the Existence of Three Shock Waves , On the Determination of the Velocity of a Projectile from the Beat Waves Produced by Interference with the Waves of Modified Frequency Reflected from

2673-509: The Chandrasekhar limit and the Chandra X-Ray Observatory , are named after him. Chandrasekhar worked on a wide variety of problems in physics during his lifetime, contributing to the contemporary understanding of stellar structure , white dwarfs , stellar dynamics , stochastic process , radiative transfer , the quantum theory of the hydrogen anion , hydrodynamic and hydromagnetic stability, turbulence , equilibrium and

2754-755: The Creative Commons license CC-BY-SA 4.0. Non-open access articles accepted before that date will be free to access but will still need permission to reuse. The journal was founded in 1895 by George Ellery Hale and James E. Keeler as The Astrophysical Journal: An International Review of Spectroscopy and Astronomical Physics . In addition to the two founding editors, there was an international board of associate editors: M. A. Cornu , Paris; N. C. Dunér , Upsala; William Huggins , London; P. Tacchini , Rome; H. C. Vogel , Potsdam, C. S. Hastings , Yale; A. A. Michelson , Chicago; E. C. Pickering , Harvard; H. A. Rowland , Johns Hopkins; and C. A. Young , Princeton. It

2835-529: The Nobel Prize in Physics in 1983 for his studies on the physical processes important to the structure and evolution of stars . Chandrasekhar accepted this honour, but was upset the citation mentioned only his earliest work, seeing it as a denigration of a lifetime's achievement. He shared it with William A. Fowler . Chandrasekhar's most notable work is on the astrophysical Chandrasekhar limit . The limit gives

2916-616: The University of Chicago towards the establishment of the Subrahmanyan Chandrasekhar Memorial Fellowship. First awarded in the year 2000, this fellowship is given annually to an outstanding applicant to graduate school in the PhD programs of the department of physics or the department of astronomy and astrophysics. S. Chandrasekhar Prize of Plasma Physics is an award given by Association of Asia Pacific Physical Societies (AAPS) to outstanding plasma physicists, started in

2997-646: The University of Chicago , he did some of his studies at the Yerkes Observatory , and served as editor of The Astrophysical Journal from 1952 to 1971. He was on the faculty at Chicago from 1937 until his death in 1995 at the age of 84, and was the Morton D. Hull Distinguished Service Professor of Theoretical Astrophysics. Subrahmanyan was born in Lahore on 19 October 1910 of the British Raj (present-day Pakistan ) in

3078-483: The hydrostatic equation together with the nonrelativistic Fermi gas equation of state , and also treated the case of a relativistic Fermi gas, giving rise to the value of the limit shown above. Chandrasekhar reviews this work in his Nobel Prize lecture. The existence of a related limit, based on the conceptual breakthrough of combining relativity with Fermi degeneracy, was first established in separate papers published by Wilhelm Anderson and E. C. Stoner for

3159-409: The statistical mechanics of the degenerate electron gas in white dwarf stars, providing relativistic corrections to Fowler's previous work (see Legacy below). In his first year at Cambridge, as a research student of Fowler, Chandrasekhar spent his time calculating mean opacities and applying his results to the construction of an improved model for the limiting mass of the degenerate star. At

3240-436: The 1930s. Instead, Eddington's heavy-handed intervention lent weighty support to the conservative community astrophysicists, who steadfastly refused even to consider the idea that stars might collapse to nothing. As a result, Chandra's work was almost forgotten. However, Chandrasekhar chose to move on, leaving the study of stellar structure to focus on stellar dynamics. In 1983 in recognition for his work, Chandrasekhar shared

3321-435: The 1960s, he studied both the equilibrium and the stability of ellipsoidal figures of equilibrium, and general relativity. During the period, 1971 to 1983 he studied the mathematical theory of black holes , and, finally, during the late 80s, he worked on the theory of colliding gravitational waves . Chandra worked closely with his students and expressed pride in the fact that over a 50-year period (from roughly 1930 to 1980),

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3402-430: The Chandrasekhar limit, its central density increases, and, as a result of compressional heating, its temperature also increases. This eventually ignites nuclear fusion reactions, leading to an immediate carbon detonation , which disrupts the star and causes the supernova. A strong indication of the reliability of Chandrasekhar's formula is that the absolute magnitudes of supernovae of Type Ia are all approximately

3483-443: The Chandrasekhar limit. These include SN 2006gz , SN 2007if , and SN 2009dc . The super-Chandrasekhar mass white dwarfs that gave rise to these supernovae are believed to have had masses up to 2.4–2.8  solar masses . One way to potentially explain the problem of the Champagne Supernova was considering it the result of an aspherical explosion of a white dwarf. However, spectropolarimetric observations of SN 2009dc showed it had

3564-561: The Projectile and The normal reflection of a blast wave . Chandrasekhar's expertise in hydrodynamics led Robert Oppenheimer to invite him to join the Manhattan Project at Los Alamos, but delays in the processing of his security clearance prevented him from contributing to the project. It has been rumoured that he visited the Calutron project. He wrote that his scientific research

3645-553: The age of 12. In middle school his father taught him mathematics and physics and his mother taught him Tamil . He later attended the Hindu High School , Triplicane , Madras during the years 1922–25. Subsequently, he studied at Presidency College, Madras (affiliated to the University of Madras ) from 1925 to 1930, writing his first paper, "The Compton Scattering and the New Statistics ", in 1929 after being inspired by

3726-475: The average age of his co-author collaborators had remained the same, at around 30. He insisted that students address him as "Prof. Chandrasekhar" until they received their PhD degree, after which time they (as other colleagues) were encouraged to address him as "Chandra". When Chandrasekhar was working at the Yerkes Observatory in 1940s, he would drive 150 miles (240 km) to and from every weekend to teach

3807-405: The capture of electrons by protons in the process of electron capture , leading to the emission of neutrinos . The decrease in gravitational potential energy of the collapsing core releases a large amount of energy on the order of 10   J (100  foes ). Most of this energy is carried away by the emitted neutrinos and the kinetic energy of the expanding shell of gas; only about 1%

3888-439: The core, since iron nuclei are incapable of generating further energy through fusion. If the core becomes sufficiently dense, electron degeneracy pressure will play a significant part in stabilizing it against gravitational collapse. If a main-sequence star is not too massive (less than approximately 8 solar masses ), it eventually sheds enough mass to form a white dwarf having mass below the Chandrasekhar limit, which consists of

3969-544: The electrons and nuclei and effects caused by nonzero temperature. Lieb and Yau have given a rigorous derivation of the limit from a relativistic many-particle Schrödinger equation . In 1926, the British physicist Ralph H. Fowler observed that the relationship between the density, energy, and temperature of white dwarfs could be explained by viewing them as a gas of nonrelativistic, non-interacting electrons and nuclei that obey Fermi–Dirac statistics . This Fermi gas model

4050-423: The electrons are no longer negligible relative to their rest masses. The velocities of the electrons approach the speed of light, and special relativity must be taken into account. In the strongly relativistic limit, the equation of state takes the form P = K 2 ρ . This yields a polytrope of index 3, which has a total mass, M limit , depending only on K 2 . For a fully relativistic treatment,

4131-421: The energy of the electrons increases on compression, so pressure must be exerted on the electron gas to compress it, producing electron degeneracy pressure. With sufficient compression, electrons are forced into nuclei in the process of electron capture , relieving the pressure. In the nonrelativistic case, electron degeneracy pressure gives rise to an equation of state of the form P = K 1 ρ , where P

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4212-467: The equation of state used interpolates between the equations P = K 1 ρ for small ρ and P = K 2 ρ for large ρ . When this is done, the model radius still decreases with mass, but becomes zero at M limit . This is the Chandrasekhar limit. The curves of radius against mass for the non-relativistic and relativistic models are shown in the graph. They are colored blue and green, respectively. μ e has been set equal to 2. Radius

4293-458: The fellowship that he had already made arrangements to study under Milne that autumn at Oxford, even going to the extent of renting a flat there. During this time, Chandrasekhar became acquainted with British physicist Sir Arthur Eddington . Eddington took an interest in his work, but in January, 1935, gave a talk severely criticizing Chandrasekhar's work (see #Dispute with Eddington and Chandrasekhar–Eddington dispute ). In 1935, Chandrasekhar

4374-403: The former core of the star. For more-massive stars, electron degeneracy pressure does not keep the iron core from collapsing to very great density, leading to formation of a neutron star , black hole , or, speculatively, a quark star . (For very massive, low- metallicity stars, it is also possible that instabilities destroy the star completely.) During the collapse, neutrons are formed by

4455-574: The increasing financial demands of the University of Chicago Press. Compared to journals in other scientific disciplines, The Astrophysical Journal has a larger (> 85%) acceptance rate, which, however, is similar to other journals covering astronomy and astrophysics. On January 1, 2022, the AAS Journals, including ApJ, changed to an open access model, with access restrictions and subscription charges removed from previously published papers. Articles accepted after October 11, 2022, will be published under

4536-590: The language and methods of ordinary calculus. The effort resulted in the book Newton's Principia for the Common Reader , published in 1995. Chandrasekhar also worked on collision of gravitational waves, and algebraically special perturbations. Chandrasekhar was the nephew of C. V. Raman , who was awarded the Nobel Prize for Physics in 1930. Chandrasekhar married Lalitha Doraiswamy in September 1936. He met her as

4617-509: The limit aroused controversy, owing to the opposition of the British astrophysicist Arthur Eddington . Eddington was aware that the existence of black holes was theoretically possible, and also realized that the existence of the limit made their formation possible. However, he was unwilling to accept that this could happen. After a talk by Chandrasekhar on the limit in 1935, he replied: The star has to go on radiating and radiating and contracting and contracting until, I suppose, it gets down to

4698-534: The mass of a white dwarf could not exceed 1.44 times that of the Sun – the Chandrasekhar limit . Chandrasekhar revised the models of stellar dynamics first outlined by Jan Oort and others by considering the effects of fluctuating gravitational fields within the Milky Way on stars rotating about the galactic centre. His solution to this complex dynamical problem involved a set of twenty partial differential equations, describing

4779-452: The maximum mass of a white dwarf star, ~1.44 solar masses , or equivalently, the minimum mass that must be exceeded for a star to collapse into a neutron star or black hole (following a supernova ). The limit was first calculated by Chandrasekhar in 1930 during his maiden voyage from India to Cambridge, England for his graduate studies. In 1979, NASA named the third of its four " Great Observatories " after Chandrasekhar. This followed

4860-656: The meetings of the Royal Astronomical Society , he met E. A. Milne . At the invitation of Max Born he spent the summer of 1931, his second year of post-graduate studies, at Born's institute at Göttingen , working on opacities, atomic absorption coefficients , and model stellar photospheres . On the advice of P. A. M. Dirac , he spent his final year of graduate studies at the Institute for Theoretical Physics in Copenhagen , where he met Niels Bohr . After receiving

4941-654: The other opening had been filled by Bengt Stromgren , a Danish theorist. Following a recommendation from Kuiper, Struve invited Chandrasekhar to Yerkes in March 1936 and offered him the job. Though Chandrasekhar was keenly interested, he initially declined the offer and left for England; after Hutchins sent a radiogram to Chandrasekhar during the voyage, he finally accepted, returning to Yerkes as an assistant professor of Theoretical Astrophysics in December 1936. Hutchins also intervened on an occasion where Chandra's participation on teaching

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5022-451: The physics of degenerate matter . Frenkel's work, however, was ignored by the astronomical and astrophysical community. A series of papers published between 1931 and 1935 had its beginning on a trip from India to England in 1930, where the Indian physicist Subrahmanyan Chandrasekhar worked on the calculation of the statistics of a degenerate Fermi gas. In these papers, Chandrasekhar solved

5103-489: The same; at maximum luminosity, M V is approximately −19.3, with a standard deviation of no more than 0.3. A 1-sigma interval therefore represents a factor of less than 2 in luminosity. This seems to indicate that all type Ia supernovae convert approximately the same amount of mass to energy. In April 2003, the Supernova Legacy Survey observed a type Ia supernova, designated SNLS-03D3bb , in

5184-498: The scientific knowledge about the structure of stars, stellar evolution and black holes. He was awarded the 1983 Nobel Prize in physics along with William A. Fowler for theoretical studies of the physical processes of importance to the structure and evolution of the stars. His mathematical treatment of stellar evolution yielded many of the current theoretical models of the later evolutionary stages of massive stars and black holes . Many concepts, institutions and inventions, including

5265-417: The stability of ellipsoidal figures of equilibrium , general relativity , mathematical theory of black holes and theory of colliding gravitational waves. At the University of Cambridge , he developed a theoretical model explaining the structure of white dwarf stars that took into account the relativistic variation of mass with the velocities of electrons that comprise their degenerate matter. He showed that

5346-410: The theory of white dwarfs , during the years 1929 to 1939, and subsequently focused on stellar dynamics , theory of Brownian motion from 1939 to 1943. Next, he concentrated on the theory of radiative transfer and the quantum theory of the negative ion of hydrogen from 1943 to 1950. This was followed by sustained work on turbulence and hydrodynamic and hydromagnetic stability from 1950 to 1961. In

5427-556: The time, owing to Eddington's status, they were unwilling to publicly support Chandrasekhar. Through the rest of his life, Eddington held to his position in his writings, including his work on his fundamental theory . The drama associated with this disagreement is one of the main themes of Empire of the Stars , Arthur I. Miller 's biography of Chandrasekhar. In Miller's view: Chandra's discovery might well have transformed and accelerated developments in both physics and astrophysics in

5508-472: The two compared each other's theories in publications. Chandrasekhar ultimately completed his theory of white dwarfs in 1939, receiving praise from others in the field. Eddington died in 1944, and despite their disagreements, Chandrasekhar continued to state that he admired Eddington and considered him a friend. During World War II, Chandrasekhar worked at the Ballistic Research Laboratory at

5589-468: The year 2014. The Chandra Astrophysics Institute (CAI) is a program offered for high school students who are interested in astrophysics mentored by MIT scientists and sponsored by the Chandra X-ray Observatory . Carl Sagan praised him in the book The Demon-Haunted World : "I discovered what true mathematical elegance is from Subrahmanyan Chandrasekhar." On 19 October 2017, Google showed

5670-463: Was also confirmed many times in his other talks. Kameshwar C. Wali quoted him saying: "I am not religious in any sense; in fact, I consider myself an atheist." In an interview with Kevin Krisciunas at the University of Chicago, on 6 October 1987, Chandrasekhar commented: "Of course, he ( Otto Struve ) knew I was an atheist, and he never brought up the subject with me". Chandrasekhar was awarded half of

5751-410: Was built by NASA in 1966 at the university, Chandrasekhar occupied one of the four corner offices on the second floor. (The other corners housed John A. Simpson , Peter Meyer , and Eugene N. Parker .) Chandrasekhar lived at 4800 Lake Shore Drive after the high-rise apartment complex was built in the late 1960s, and later at 5550 Dorchester Building. After graduating from Cambridge, Chandrasekhar, who

5832-617: Was editor of The Astrophysical Journal . When Eugene Parker submitted a paper on his discovery of solar wind in 1957, two eminent reviewers rejected the paper. However, since Chandra as an editor could not find any mathematical flaws in Parker's work, he went ahead and published the paper in 1958. During the years 1990 to 1995, Chandrasekhar worked on a project devoted to explaining the detailed geometric arguments in Sir Isaac Newton 's Philosophiae Naturalis Principia Mathematica using

5913-684: Was in close contact with Arthur Eddington, presented a full solution to his stellar equation at the Royal Astronomical Society meeting in 1935. Eddington booked a talk right after Chandrasekhar, where he openly criticized Chandrasekhar's theory. This depressed Chandrasekhar and sparked a scientific dispute. Eddington refused to accept a limit for the mass of a star and was proposing an alternative model. Chandrasekhar sought support from prominent physicists like Léon Rosenfeld , Niels Bohr and Christian Møller who found Eddington's arguments lacking. The tension persisted through 1930s, as Eddington continued to openly criticize Chandrasekhar during meetings and

5994-541: Was intended that the journal would fill the gap between journals in astronomy and physics, providing a venue for publication of articles on astronomical applications of the spectroscope ; on laboratory research closely allied to astronomical physics, including wavelength determinations of metallic and gaseous spectra and experiments on radiation and absorption ; on theories of the Sun, Moon, planets, comets, meteors, and nebulae; and on instrumentation for telescopes and laboratories. The further development of ApJ up to 1995

6075-547: Was invited by the director of the Harvard Observatory, Harlow Shapley , to be a visiting lecturer in theoretical astrophysics for a three-month period. He travelled to the United States in December. During his visit to Harvard, Chandrasekhar greatly impressed Shapley, but declined his offer of a Harvard research fellowship. At the same time, Chandrasekhar met Gerard Kuiper , a noted Dutch astrophysical observationalist who

6156-496: Was motivated by his desire to participate in the progress of different subjects in science to the best of his ability, and that the prime motive underlying his work was systematization . "What a scientist tries to do essentially is to select a certain domain, a certain aspect, or a certain detail, and see if that takes its appropriate place in a general scheme which has form and coherence; and, if not, to seek further information which would help him to do that". Chandrasekhar developed

6237-577: Was not aware of either Stoner's or Anderson's work at the time. His work was therefore independent, but, more to the point, he adopted Eddington's polytropes for his models which could, therefore, be in hydrostatic equilibrium, which constant density stars cannot, and real ones must be." This value was also computed in 1932 by the Soviet physicist Lev Landau , who, however, did not apply it to white dwarfs and concluded that quantum laws might be invalid for stars heavier than 1.5 solar mass. Chandrasekhar's work on

6318-506: Was outlined by Helmut Abt in an article entitled "Some Statistical Highlights of the Astrophysical Journal " in 1995. The following persons have been editors-in-chief of the journal: Subrahmanyan Chandrasekhar Subrahmanyan Chandrasekhar FRS ( / ˌ tʃ ə n d r ə ˈ ʃ eɪ k ər / ; 19 October 1910 – 21 August 1995) was an Indian-American theoretical physicist who made significant contributions to

6399-453: Was the Indian physicist and Nobel laureate Chandrasekhara Venkata Raman . His mother was devoted to intellectual pursuits, had translated Henrik Ibsen 's A Doll's House into Tamil and is credited with arousing Chandra's intellectual curiosity at an early age. The family moved from Lahore to Allahabad in 1916, and finally settled in Madras in 1918. Chandrasekhar was tutored at home until

6480-458: Was then a leading authority on white dwarfs. Kuiper had recently been recruited by Otto Struve , the director of the Yerkes Observatory in Williams Bay, Wisconsin , which was run by the University of Chicago , and the university's president, Robert Maynard Hutchins . Having known of Chandrasekhar, Struve was then considering him for one of three faculty posts in astrophysics, along with Kuiper;

6561-421: Was then used by the British physicist Edmund Clifton Stoner in 1929 to calculate the relationship among the mass, radius, and density of white dwarfs, assuming they were homogeneous spheres. Wilhelm Anderson applied a relativistic correction to this model, giving rise to a maximum possible mass of approximately 1.37 × 10  kg . In 1930, Stoner derived the internal energy – density equation of state for

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