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119-676: The traditional name Bellatrix is from the Latin bellātrix "female warrior". It first appeared in the works of Abu Ma'shar al-Balkhi and Johannes Hispalensis , where it originally referred to Capella , but was transferred to Gamma Orionis by the Vienna school of astronomers in the 15th century, and appeared in contemporary reprints of the Alfonsine tables . In 2016, the International Astronomical Union organized

238-542: A Working Group on Star Names (WGSN) to catalog and standardize proper names for stars. The WGSN's first bulletin of July 2016 included a table of the first two batches of names approved by the WGSN; which included Bellatrix for this star. It is now so entered in the IAU Catalog of Star Names. The designation of Bellatrix as γ Orionis ( Latinized to Gamma Orionis) was made by Johann Bayer in 1603. The "gamma" designation

357-469: A November 1783 letter to Henry Cavendish , and in the early 20th century, physicists used the term "gravitationally collapsed object". Science writer Marcia Bartusiak traces the term "black hole" to physicist Robert H. Dicke , who in the early 1960s reportedly compared the phenomenon to the Black Hole of Calcutta , notorious as a prison where people entered but never left alive. The term "black hole"

476-428: A Schwarzschild black hole (i.e., non-rotating and not charged) cannot avoid being carried into the singularity once they cross the event horizon. They can prolong the experience by accelerating away to slow their descent, but only up to a limit. When they reach the singularity, they are crushed to infinite density and their mass is added to the total of the black hole. Before that happens, they will have been torn apart by

595-507: A black hole acts like an ideal black body , as it reflects no light. Quantum field theory in curved spacetime predicts that event horizons emit Hawking radiation , with the same spectrum as a black body of a temperature inversely proportional to its mass. This temperature is of the order of billionths of a kelvin for stellar black holes , making it essentially impossible to observe directly. Objects whose gravitational fields are too strong for light to escape were first considered in

714-506: A black hole appears to slow as it approaches the event horizon, taking an infinite amount of time to reach it. At the same time, all processes on this object slow down, from the viewpoint of a fixed outside observer, causing any light emitted by the object to appear redder and dimmer, an effect known as gravitational redshift . Eventually, the falling object fades away until it can no longer be seen. Typically this process happens very rapidly with an object disappearing from view within less than

833-462: A black hole can be inferred through its interaction with other matter and with electromagnetic radiation such as visible light. Any matter that falls toward a black hole can form an external accretion disk heated by friction , forming quasars , some of the brightest objects in the universe. Stars passing too close to a supermassive black hole can be shredded into streamers that shine very brightly before being "swallowed." If other stars are orbiting

952-489: A black hole is the appearance of an event horizon—a boundary in spacetime through which matter and light can pass only inward towards the mass of the black hole. Nothing, not even light, can escape from inside the event horizon. The event horizon is referred to as such because if an event occurs within the boundary, information from that event cannot reach an outside observer, making it impossible to determine whether such an event occurred. As predicted by general relativity,

1071-512: A black hole, as determined by the radius of the event horizon, or Schwarzschild radius, is proportional to the mass, M , through where r s is the Schwarzschild radius and M ☉ is the mass of the Sun . For a black hole with nonzero spin and/or electric charge, the radius is smaller, until an extremal black hole could have an event horizon close to The defining feature of

1190-524: A black hole, their orbits can be used to determine the black hole's mass and location. Such observations can be used to exclude possible alternatives such as neutron stars. In this way, astronomers have identified numerous stellar black hole candidates in binary systems and established that the radio source known as Sagittarius A* , at the core of the Milky Way galaxy, contains a supermassive black hole of about 4.3 million solar masses. The idea of

1309-455: A body so big that even light could not escape was briefly proposed by English astronomical pioneer and clergyman John Michell in a letter published in November 1784. Michell's simplistic calculations assumed such a body might have the same density as the Sun, and concluded that one would form when a star's diameter exceeds the Sun's by a factor of 500, and its surface escape velocity exceeds

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1428-462: A central object. In general relativity, however, there exists an innermost stable circular orbit (often called the ISCO), for which any infinitesimal inward perturbations to a circular orbit will lead to spiraling into the black hole, and any outward perturbations will, depending on the energy, result in spiraling in, stably orbiting between apastron and periastron, or escaping to infinity. The location of

1547-424: A common motion through space, along with the stars of Orion's Belt : Alnitak (Zeta Orionis), Alnilam (Epsilon Orionis), and Mintaka (Delta Orionis). However, this is no longer believed to be the case, as Bellatrix is now known to be much closer than the rest of the group. It is not known to have a stellar companion, although researchers Maria-Fernanda Nieva and Norbert Przybilla raised the possibility it might be

1666-404: A density as the Sun. Firstly, the force of gravitation would be so great that light would be unable to escape from it, the rays falling back to the star like a stone to the earth. Secondly, the red shift of the spectral lines would be so great that the spectrum would be shifted out of existence. Thirdly, the mass would produce so much curvature of the spacetime metric that space would close up around

1785-526: A faster pace. It is characterised by greater use of prepositions, and word order that is closer to modern Romance languages, for example, while grammatically retaining more or less the same formal rules as Classical Latin. Ultimately, Latin diverged into a distinct written form, where the commonly spoken form was perceived as a separate language, for instance early French or Italian dialects, that could be transcribed differently. It took some time for these to be viewed as wholly different from Latin however. After

1904-743: A few in German , Dutch , Norwegian , Danish and Swedish . Latin is still spoken in Vatican City, a city-state situated in Rome that is the seat of the Catholic Church . The works of several hundred ancient authors who wrote in Latin have survived in whole or in part, in substantial works or in fragments to be analyzed in philology . They are in part the subject matter of the field of classics . Their works were published in manuscript form before

2023-404: A few. Famous and well regarded writers included Petrarch, Erasmus, Salutati , Celtis , George Buchanan and Thomas More . Non fiction works were long produced in many subjects, including the sciences, law, philosophy, historiography and theology. Famous examples include Isaac Newton 's Principia . Latin was also used as a convenient medium for translations of important works first written in

2142-473: A mathematical curiosity; it was not until the 1960s that theoretical work showed they were a generic prediction of general relativity. The discovery of neutron stars by Jocelyn Bell Burnell in 1967 sparked interest in gravitationally collapsed compact objects as a possible astrophysical reality. The first black hole known was Cygnus X-1 , identified by several researchers independently in 1971. Black holes of stellar mass form when massive stars collapse at

2261-560: A native language, Medieval Latin was used across Western and Catholic Europe during the Middle Ages as a working and literary language from the 9th century to the Renaissance , which then developed a classicizing form, called Renaissance Latin . This was the basis for Neo-Latin which evolved during the early modern period . In these periods Latin was used productively and generally taught to be written and spoken, at least until

2380-431: A non-rotating black hole, this region takes the shape of a single point; for a rotating black hole it is smeared out to form a ring singularity that lies in the plane of rotation. In both cases, the singular region has zero volume. It can also be shown that the singular region contains all the mass of the black hole solution. The singular region can thus be thought of as having infinite density . Observers falling into

2499-567: A result, the list has variants, as well as alternative names. In addition to the historical phases, Ecclesiastical Latin refers to the styles used by the writers of the Roman Catholic Church from late antiquity onward, as well as by Protestant scholars. The earliest known form of Latin is Old Latin, also called Archaic or Early Latin, which was spoken from the Roman Kingdom , traditionally founded in 753 BC, through

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2618-495: A second. On the other hand, indestructible observers falling into a black hole do not notice any of these effects as they cross the event horizon. According to their own clocks, which appear to them to tick normally, they cross the event horizon after a finite time without noting any singular behaviour; in classical general relativity, it is impossible to determine the location of the event horizon from local observations, due to Einstein's equivalence principle . The topology of

2737-407: A separate language, existing more or less in parallel with the literary or educated Latin, but this is now widely dismissed. The term 'Vulgar Latin' remains difficult to define, referring both to informal speech at any time within the history of Latin, and the kind of informal Latin that had begun to move away from the written language significantly in the post-Imperial period, that led ultimately to

2856-419: A situation where quantum effects should describe these actions, due to the extremely high density and therefore particle interactions. To date, it has not been possible to combine quantum and gravitational effects into a single theory, although there exist attempts to formulate such a theory of quantum gravity . It is generally expected that such a theory will not feature any singularities. The photon sphere

2975-709: A small number of Latin services held in the Anglican church. These include an annual service in Oxford, delivered with a Latin sermon; a relic from the period when Latin was the normal spoken language of the university. In the Western world, many organizations, governments and schools use Latin for their mottos due to its association with formality, tradition, and the roots of Western culture . Canada's motto A mari usque ad mare ("from sea to sea") and most provincial mottos are also in Latin. The Canadian Victoria Cross

3094-429: A sort of informal language academy dedicated to maintaining and perpetuating educated speech. Philological analysis of Archaic Latin works, such as those of Plautus , which contain fragments of everyday speech, gives evidence of an informal register of the language, Vulgar Latin (termed sermo vulgi , "the speech of the masses", by Cicero ). Some linguists, particularly in the nineteenth century, believed this to be

3213-527: A spectroscopic binary. A 2011 search for nearby companions failed to conclusively find any objects that share a proper motion with Bellatrix. Three nearby candidates were all found to be background stars. Some researchers suspected that Bellatrix was a member of the 32 Orionis group . They proposed that the 32 Ori group should instead be termed the Bellatrix Cluster on the basis that the sky position and distance of Bellatrix are similar to those of

3332-572: A spoken and written language by the scholarship by the Renaissance humanists . Petrarch and others began to change their usage of Latin as they explored the texts of the Classical Latin world. Skills of textual criticism evolved to create much more accurate versions of extant texts through the fifteenth and sixteenth centuries, and some important texts were rediscovered. Comprehensive versions of authors' works were published by Isaac Casaubon , Joseph Scaliger and others. Nevertheless, despite

3451-464: A standard for the B2 III type. The expected brightness of Bellatrix from this spectral type is about one magnitude brighter than calculated from its apparent magnitude and Hipparcos distance. Analysis of the observed characteristics of the star indicate that it should be a B2 main sequence star, not the giant that it appears from its spectral type. Close analysis of high resolution spectra suggest that it

3570-432: A strictly left-to-right script. During the late republic and into the first years of the empire, from about 75 BC to AD 200, a new Classical Latin arose, a conscious creation of the orators, poets, historians and other literate men, who wrote the great works of classical literature , which were taught in grammar and rhetoric schools. Today's instructional grammars trace their roots to such schools , which served as

3689-554: A student of Hendrik Lorentz , independently gave the same solution for the point mass and wrote more extensively about its properties. This solution had a peculiar behaviour at what is now called the Schwarzschild radius , where it became singular , meaning that some of the terms in the Einstein equations became infinite. The nature of this surface was not quite understood at the time. In 1924, Arthur Eddington showed that

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3808-693: A vernacular, such as those of Descartes . Latin education underwent a process of reform to classicise written and spoken Latin. Schooling remained largely Latin medium until approximately 1700. Until the end of the 17th century, the majority of books and almost all diplomatic documents were written in Latin. Afterwards, most diplomatic documents were written in French (a Romance language ) and later native or other languages. Education methods gradually shifted towards written Latin, and eventually concentrating solely on reading skills. The decline of Latin education took several centuries and proceeded much more slowly than

3927-417: A wave rather than a particle, it was unclear what, if any, influence gravity would have on escaping light waves. The modern theory of gravity, general relativity, discredits Michell's notion of a light ray shooting directly from the surface of a supermassive star, being slowed down by the star's gravity, stopping, and then free-falling back to the star's surface. Instead, spacetime itself is curved such that

4046-411: Is Veritas ("truth"). Veritas was the goddess of truth, a daughter of Saturn, and the mother of Virtue. Switzerland has adopted the country's Latin short name Helvetia on coins and stamps, since there is no room to use all of the nation's four official languages . For a similar reason, it adopted the international vehicle and internet code CH , which stands for Confoederatio Helvetica ,

4165-676: Is Ya-jungin "Owl Eyes Flicking", watching the ceremonies. To the Inuit , the appearance of Betelgeuse and Bellatrix high in the southern sky after sunset marked the beginning of spring and lengthening days in late February and early March. The two stars were known as Akuttujuuk "those (two) placed far apart", referring to the distance between them, mainly to people from North Baffin Island and Melville Peninsula. Latin (language) Latin ( lingua Latina , pronounced [ˈlɪŋɡʷa ɫaˈtiːna] , or Latinum [ɫaˈtiːnʊ̃] )

4284-897: Is a classical language belonging to the Italic branch of the Indo-European languages . Latin was originally spoken by the Latins in Latium (now known as Lazio ), the lower Tiber area around Rome , Italy. Through the expansion of the Roman Republic it became the dominant language in the Italian Peninsula and subsequently throughout the Roman Empire . By the late Roman Republic , Old Latin had evolved into standardized Classical Latin . Vulgar Latin refers to

4403-508: Is a region of spacetime wherein gravity is so strong that no matter or electromagnetic energy (e.g. light ) can escape it. Albert Einstein 's theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole. The boundary of no escape is called the event horizon . A black hole has a great effect on the fate and circumstances of an object crossing it, but it has no locally detectable features according to general relativity. In many ways,

4522-640: Is a reversal of the original phrase Non terrae plus ultra ("No land further beyond", "No further!"). According to legend , this phrase was inscribed as a warning on the Pillars of Hercules , the rocks on both sides of the Strait of Gibraltar and the western end of the known, Mediterranean world. Charles adopted the motto following the discovery of the New World by Columbus, and it also has metaphorical suggestions of taking risks and striving for excellence. In

4641-414: Is a spectroscopic binary composed of two similar stars less luminous than a B2 giant. Bellatrix is a massive star with about 7.7 times the mass and 5.8 times the radius of the Sun. It has an estimated age of approximately 25 million years—old enough for a star of this mass to consume the hydrogen at its core and begin to evolve away from the main sequence into a giant star . The effective temperature of

4760-432: Is a spherical boundary where photons that move on tangents to that sphere would be trapped in a non-stable but circular orbit around the black hole. For non-rotating black holes, the photon sphere has a radius 1.5 times the Schwarzschild radius. Their orbits would be dynamically unstable , hence any small perturbation, such as a particle of infalling matter, would cause an instability that would grow over time, either setting

4879-450: Is commonly given to the third-brightest star in each constellation. Bellatrix has been used as both a photometric and spectral standard star, but both characteristics have been shown to be unreliable. In 1963, Bellatrix was included with a set of bright stars used to define the UBV magnitude system . These are used for comparison with other stars to check for variability, and so by definition,

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4998-552: Is found in any widespread language, the languages of Spain, France, Portugal, and Italy have retained a remarkable unity in phonological forms and developments, bolstered by the stabilising influence of their common Christian (Roman Catholic) culture. It was not until the Muslim conquest of Spain in 711, cutting off communications between the major Romance regions, that the languages began to diverge seriously. The spoken Latin that would later become Romanian diverged somewhat more from

5117-594: Is identical to that of any other body of the same mass. Solutions describing more general black holes also exist. Non-rotating charged black holes are described by the Reissner–Nordström metric , while the Kerr metric describes a non-charged rotating black hole. The most general stationary black hole solution known is the Kerr–Newman metric, which describes a black hole with both charge and angular momentum. While

5236-689: Is modelled after the British Victoria Cross which has the inscription "For Valour". Because Canada is officially bilingual, the Canadian medal has replaced the English inscription with the Latin Pro Valore . Spain's motto Plus ultra , meaning "even further", or figuratively "Further!", is also Latin in origin. It is taken from the personal motto of Charles V , Holy Roman Emperor and King of Spain (as Charles I), and

5355-548: Is taken from the rotational energy of the black hole. Thereby the rotation of the black hole slows down. A variation of the Penrose process in the presence of strong magnetic fields, the Blandford–Znajek process is considered a likely mechanism for the enormous luminosity and relativistic jets of quasars and other active galactic nuclei . In Newtonian gravity , test particles can stably orbit at arbitrary distances from

5474-1011: Is taught at many high schools, especially in Europe and the Americas. It is most common in British public schools and grammar schools, the Italian liceo classico and liceo scientifico , the German Humanistisches Gymnasium and the Dutch gymnasium . Occasionally, some media outlets, targeting enthusiasts, broadcast in Latin. Notable examples include Radio Bremen in Germany, YLE radio in Finland (the Nuntii Latini broadcast from 1989 until it

5593-409: Is the only vacuum solution that is spherically symmetric . This means there is no observable difference at a distance between the gravitational field of such a black hole and that of any other spherical object of the same mass. The popular notion of a black hole "sucking in everything" in its surroundings is therefore correct only near a black hole's horizon; far away, the external gravitational field

5712-414: Is the result of a process known as frame-dragging ; general relativity predicts that any rotating mass will tend to slightly "drag" along the spacetime immediately surrounding it. Any object near the rotating mass will tend to start moving in the direction of rotation. For a rotating black hole, this effect is so strong near the event horizon that an object would have to move faster than the speed of light in

5831-552: Is thought to have generated a black hole shortly afterward, have refined the TOV limit estimate to ~2.17  M ☉ . Oppenheimer and his co-authors interpreted the singularity at the boundary of the Schwarzschild radius as indicating that this was the boundary of a bubble in which time stopped. This is a valid point of view for external observers, but not for infalling observers. The hypothetical collapsed stars were called "frozen stars", because an outside observer would see

5950-543: The Corpus Inscriptionum Latinarum (CIL). Authors and publishers vary, but the format is about the same: volumes detailing inscriptions with a critical apparatus stating the provenance and relevant information. The reading and interpretation of these inscriptions is the subject matter of the field of epigraphy . About 270,000 inscriptions are known. The Latin influence in English has been significant at all stages of its insular development. In

6069-583: The Holy See , the primary language of its public journal , the Acta Apostolicae Sedis , and the working language of the Roman Rota . Vatican City is also home to the world's only automatic teller machine that gives instructions in Latin. In the pontifical universities postgraduate courses of Canon law are taught in Latin, and papers are written in the same language. There are

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6188-700: The LIGO Scientific Collaboration and the Virgo collaboration announced the first direct detection of gravitational waves , representing the first observation of a black hole merger. On 10 April 2019, the first direct image of a black hole and its vicinity was published, following observations made by the Event Horizon Telescope (EHT) in 2017 of the supermassive black hole in Messier 87's galactic centre . As of 2023 ,

6307-574: The Middle Ages , borrowing from Latin occurred from ecclesiastical usage established by Saint Augustine of Canterbury in the 6th century or indirectly after the Norman Conquest , through the Anglo-Norman language . From the 16th to the 18th centuries, English writers cobbled together huge numbers of new words from Latin and Greek words, dubbed " inkhorn terms ", as if they had spilled from a pot of ink. Many of these words were used once by

6426-483: The Oppenheimer–Snyder model in their paper "On Continued Gravitational Contraction", which predicted the existence of black holes. In the paper, which made no reference to Einstein's recent publication, Oppenheimer and Snyder used Einstein's own theory of general relativity to show the conditions on how a black hole could develop, for the first time in contemporary physics. In 1958, David Finkelstein identified

6545-576: The Roman Rite of the Catholic Church at the Vatican City . The church continues to adapt concepts from modern languages to Ecclesiastical Latin of the Latin language. Contemporary Latin is more often studied to be read rather than spoken or actively used. Latin has greatly influenced the English language , along with a large number of others, and historically contributed many words to

6664-569: The Romance languages . During the Classical period, informal language was rarely written, so philologists have been left with only individual words and phrases cited by classical authors, inscriptions such as Curse tablets and those found as graffiti . In the Late Latin period, language changes reflecting spoken (non-classical) norms tend to be found in greater quantities in texts. As it

6783-636: The Western Roman Empire fell in 476 and Germanic kingdoms took its place, the Germanic people adopted Latin as a language more suitable for legal and other, more formal uses. While the written form of Latin was increasingly standardized into a fixed form, the spoken forms began to diverge more greatly. Currently, the five most widely spoken Romance languages by number of native speakers are Spanish , Portuguese , French , Italian , and Romanian . Despite dialectal variation, which

6902-401: The apparent magnitude of Bellatrix was set to 1.64. However, when an all-sky photometry survey was carried out in 1988, this star was suspected to be variable. It was measured ranging in apparent magnitude from 1.59 to 1.64, and appears to be a low amplitude, possibly irregular variable. The spectral types for O and early B stars were defined more rigorously in 1971 and Bellatrix was used as

7021-519: The geodesic that light travels on never leaves the surface of the "star" (black hole). In 1915, Albert Einstein developed his theory of general relativity , having earlier shown that gravity does influence light's motion. Only a few months later, Karl Schwarzschild found a solution to the Einstein field equations that describes the gravitational field of a point mass and a spherical mass. A few months after Schwarzschild, Johannes Droste ,

7140-431: The 18th century by John Michell and Pierre-Simon Laplace . In 1916, Karl Schwarzschild found the first modern solution of general relativity that would characterise a black hole. Due to his influential research, the Schwarzschild metric is named after him. David Finkelstein , in 1958, first published the interpretation of "black hole" as a region of space from which nothing can escape. Black holes were long considered

7259-545: The 2020 Nobel Prize in Physics , Hawking having died in 2018. Based on observations in Greenwich and Toronto in the early 1970s, Cygnus X-1 , a galactic X-ray source discovered in 1964, became the first astronomical object commonly accepted to be a black hole. Work by James Bardeen , Jacob Bekenstein , Carter, and Hawking in the early 1970s led to the formulation of black hole thermodynamics . These laws describe

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7378-413: The 32 Ori group. The proper motion of Bellatrix deviates significantly from the mean motion of the group, leaving its membership in question. However, it may be possible to reconcile membership if the divergent velocity is the result of an unseen companion. For example, a face-on orbit with a black hole companion orbiting ~100  AU from the star with a period measured in centuries could account for

7497-637: The British Crown. The motto is featured on all presently minted coinage and has been featured in most coinage throughout the nation's history. Several states of the United States have Latin mottos , such as: Many military organizations today have Latin mottos, such as: Some law governing bodies in the Philippines have Latin mottos, such as: Some colleges and universities have adopted Latin mottos, for example Harvard University 's motto

7616-613: The English lexicon , particularly after the Christianization of the Anglo-Saxons and the Norman Conquest . Latin and Ancient Greek roots are heavily used in English vocabulary in theology , the sciences , medicine , and law . A number of phases of the language have been recognized, each distinguished by subtle differences in vocabulary, usage, spelling, and syntax. There are no hard and fast rules of classification; different scholars emphasize different features. As

7735-599: The Grinch Stole Christmas! , The Cat in the Hat , and a book of fairy tales, " fabulae mirabiles ", are intended to garner popular interest in the language. Additional resources include phrasebooks and resources for rendering everyday phrases and concepts into Latin, such as Meissner's Latin Phrasebook . Some inscriptions have been published in an internationally agreed, monumental, multivolume series,

7854-401: The Kerr singularity, which leads to problems with causality like the grandfather paradox . It is expected that none of these peculiar effects would survive in a proper quantum treatment of rotating and charged black holes. The appearance of singularities in general relativity is commonly perceived as signalling the breakdown of the theory. This breakdown, however, is expected; it occurs in

7973-505: The Schwarzschild surface as an event horizon, "a perfect unidirectional membrane: causal influences can cross it in only one direction". This did not strictly contradict Oppenheimer's results, but extended them to include the point of view of infalling observers. Finkelstein's solution extended the Schwarzschild solution for the future of observers falling into a black hole. A complete extension had already been found by Martin Kruskal , who

8092-467: The United States the unofficial national motto until 1956 was E pluribus unum meaning "Out of many, one". The motto continues to be featured on the Great Seal . It also appears on the flags and seals of both houses of congress and the flags of the states of Michigan, North Dakota, New York, and Wisconsin. The motto's 13 letters symbolically represent the original Thirteen Colonies which revolted from

8211-563: The University of Kentucky, the University of Oxford and also Princeton University. There are many websites and forums maintained in Latin by enthusiasts. The Latin Misplaced Pages has more than 130,000 articles. Italian , French , Portuguese , Spanish , Romanian , Catalan , Romansh , Sardinian and other Romance languages are direct descendants of Latin. There are also many Latin borrowings in English and Albanian , as well as

8330-435: The author and then forgotten, but some useful ones survived, such as 'imbibe' and 'extrapolate'. Many of the most common polysyllabic English words are of Latin origin through the medium of Old French . Romance words make respectively 59%, 20% and 14% of English, German and Dutch vocabularies. Those figures can rise dramatically when only non-compound and non-derived words are included. Black hole A black hole

8449-463: The behaviour of a black hole in close analogy to the laws of thermodynamics by relating mass to energy, area to entropy , and surface gravity to temperature . The analogy was completed when Hawking, in 1974, showed that quantum field theory implies that black holes should radiate like a black body with a temperature proportional to the surface gravity of the black hole, predicting the effect now known as Hawking radiation . On 11 February 2016,

8568-425: The benefit of those who do not understand Latin. There are also songs written with Latin lyrics . The libretto for the opera-oratorio Oedipus rex by Igor Stravinsky is in Latin. Parts of Carl Orff 's Carmina Burana are written in Latin. Enya has recorded several tracks with Latin lyrics. The continued instruction of Latin is seen by some as a highly valuable component of a liberal arts education. Latin

8687-498: The black hole horizon, including approximately conserved quantum numbers such as the total baryon number and lepton number . This behaviour is so puzzling that it has been called the black hole information loss paradox . The simplest static black holes have mass but neither electric charge nor angular momentum. These black holes are often referred to as Schwarzschild black holes after Karl Schwarzschild who discovered this solution in 1916. According to Birkhoff's theorem , it

8806-409: The careful work of Petrarch, Politian and others, first the demand for manuscripts, and then the rush to bring works into print, led to the circulation of inaccurate copies for several centuries following. Neo-Latin literature was extensive and prolific, but less well known or understood today. Works covered poetry, prose stories and early novels, occasional pieces and collections of letters, to name

8925-415: The classicised Latin that followed through to the present are often grouped together as Neo-Latin , or New Latin, which have in recent decades become a focus of renewed study , given their importance for the development of European culture, religion and science. The vast majority of written Latin belongs to this period, but its full extent is unknown. The Renaissance reinforced the position of Latin as

9044-537: The collapse. They were partly correct: a white dwarf slightly more massive than the Chandrasekhar limit will collapse into a neutron star , which is itself stable. In 1939, Robert Oppenheimer and others predicted that neutron stars above another limit, the Tolman–Oppenheimer–Volkoff limit , would collapse further for the reasons presented by Chandrasekhar, and concluded that no law of physics

9163-465: The country's full Latin name. Some film and television in ancient settings, such as Sebastiane , The Passion of the Christ and Barbarians (2020 TV series) , have been made with dialogue in Latin. Occasionally, Latin dialogue is used because of its association with religion or philosophy, in such film/television series as The Exorcist and Lost (" Jughead "). Subtitles are usually shown for

9282-503: The decline in written Latin output. Despite having no native speakers, Latin is still used for a variety of purposes in the contemporary world. The largest organisation that retains Latin in official and quasi-official contexts is the Catholic Church . The Catholic Church required that Mass be carried out in Latin until the Second Vatican Council of 1962–1965 , which permitted the use of the vernacular . Latin remains

9401-448: The discovery of pulsars showed their physical relevance and spurred a further interest in all types of compact objects that might be formed by gravitational collapse. In this period more general black hole solutions were found. In 1963, Roy Kerr found the exact solution for a rotating black hole . Two years later, Ezra Newman found the axisymmetric solution for a black hole that is both rotating and electrically charged . Through

9520-730: The discrepancy. Bellatrix was also called the Amazon Star , which Richard Hinckley Allen proposed came from a loose translation of the Arabic name Al Najīd , the Conqueror. A c.1275 Arabic celestial globe records the name as المرزم "the lion". Bellatrix is one of the four navigational stars in Orion that are used for celestial navigation . In the 17th century catalogue of stars in the Calendarium of Al Achsasi al Mouakket , this star

9639-589: The educated and official world, Latin continued without its natural spoken base. Moreover, this Latin spread into lands that had never spoken Latin, such as the Germanic and Slavic nations. It became useful for international communication between the member states of the Holy Roman Empire and its allies. Without the institutions of the Roman Empire that had supported its uniformity, Medieval Latin

9758-407: The end of their life cycle. After a black hole has formed, it can grow by absorbing mass from its surroundings. Supermassive black holes of millions of solar masses ( M ☉ ) may form by absorbing other stars and merging with other black holes, or via direct collapse of gas clouds . There is consensus that supermassive black holes exist in the centres of most galaxies . The presence of

9877-400: The event horizon of a black hole at equilibrium is always spherical. For non-rotating (static) black holes the geometry of the event horizon is precisely spherical, while for rotating black holes the event horizon is oblate. At the centre of a black hole, as described by general relativity, may lie a gravitational singularity , a region where the spacetime curvature becomes infinite. For

9996-648: The growing tidal forces in a process sometimes referred to as spaghettification or the "noodle effect". In the case of a charged (Reissner–Nordström) or rotating (Kerr) black hole, it is possible to avoid the singularity. Extending these solutions as far as possible reveals the hypothetical possibility of exiting the black hole into a different spacetime with the black hole acting as a wormhole . The possibility of travelling to another universe is, however, only theoretical since any perturbation would destroy this possibility. It also appears to be possible to follow closed timelike curves (returning to one's own past) around

10115-703: The invention of printing and are now published in carefully annotated printed editions, such as the Loeb Classical Library , published by Harvard University Press , or the Oxford Classical Texts , published by Oxford University Press . Latin translations of modern literature such as: The Hobbit , Treasure Island , Robinson Crusoe , Paddington Bear , Winnie the Pooh , The Adventures of Tintin , Asterix , Harry Potter , Le Petit Prince , Max and Moritz , How

10234-704: The language of the Roman Rite . The Tridentine Mass (also known as the Extraordinary Form or Traditional Latin Mass) is celebrated in Latin. Although the Mass of Paul VI (also known as the Ordinary Form or the Novus Ordo) is usually celebrated in the local vernacular language, it can be and often is said in Latin, in part or in whole, especially at multilingual gatherings. It is the official language of

10353-440: The large areas where it had come to be natively spoken. However, even after the fall of Western Rome , Latin remained the common language of international communication , science, scholarship and academia in Europe until well into the early 19th century, by which time modern languages had supplanted it in common academic and political usage. Late Latin is the literary language from the 3rd century AD onward. No longer spoken as

10472-467: The late seventeenth century, when spoken skills began to erode. It then became increasingly taught only to be read. Latin grammar is highly fusional , with classes of inflections for case , number , person , gender , tense , mood , voice , and aspect . The Latin alphabet is directly derived from the Etruscan and Greek alphabets . Latin remains the official language of the Holy See and

10591-431: The later part of the Roman Republic , up to 75 BC, i.e. before the age of Classical Latin . It is attested both in inscriptions and in some of the earliest extant Latin literary works, such as the comedies of Plautus and Terence . The Latin alphabet was devised from the Etruscan alphabet . The writing later changed from what was initially either a right-to-left or a boustrophedon script to what ultimately became

10710-421: The less prestigious colloquial registers , attested in inscriptions and some literary works such as those of the comic playwrights Plautus and Terence and the author Petronius . While often called a "dead language", Latin did not undergo language death . By the 6th to 9th centuries, natural language change eventually resulted in Latin as a vernacular language evolving into distinct Romance languages in

10829-544: The mass of a black hole can take any positive value, the charge and angular momentum are constrained by the mass. The total electric charge  Q and the total angular momentum  J are expected to satisfy the inequality for a black hole of mass M . Black holes with the minimum possible mass satisfying this inequality are called extremal . Solutions of Einstein's equations that violate this inequality exist, but they do not possess an event horizon. These solutions have so-called naked singularities that can be observed from

10948-414: The microscopic level, because they are time-reversible . Because a black hole eventually achieves a stable state with only three parameters, there is no way to avoid losing information about the initial conditions: the gravitational and electric fields of a black hole give very little information about what went in. The information that is lost includes every quantity that cannot be measured far away from

11067-479: The nearest known body thought to be a black hole, Gaia BH1 , is around 1,560 light-years (480 parsecs ) away. Though only a couple dozen black holes have been found so far in the Milky Way, there are thought to be hundreds of millions, most of which are solitary and do not cause emission of radiation. Therefore, they would only be detectable by gravitational lensing . John Michell used the term "dark star" in

11186-508: The opposite direction to just stand still. The ergosphere of a black hole is a volume bounded by the black hole's event horizon and the ergosurface , which coincides with the event horizon at the poles but is at a much greater distance around the equator. Objects and radiation can escape normally from the ergosphere. Through the Penrose process , objects can emerge from the ergosphere with more energy than they entered with. The extra energy

11305-466: The other varieties, as it was largely separated from the unifying influences in the western part of the Empire. Spoken Latin began to diverge into distinct languages by the 9th century at the latest, when the earliest extant Romance writings begin to appear. They were, throughout the period, confined to everyday speech, as Medieval Latin was used for writing. For many Italians using Latin, though, there

11424-491: The outer envelope of this star is 22,000 K , which is considerably hotter than the 5,778 K on the Sun. This high temperature gives this star the blue-white hue that occurs with B-type stars . It shows a projected rotational velocity of around 52 km/s. Bellatrix may have sufficient mass to end its life in a supernova explosion. Bellatrix was thought to belong to the Orion OB1 association of stars that share

11543-425: The outside, and hence are deemed unphysical . The cosmic censorship hypothesis rules out the formation of such singularities, when they are created through the gravitational collapse of realistic matter . This is supported by numerical simulations. Due to the relatively large strength of the electromagnetic force , black holes forming from the collapse of stars are expected to retain the nearly neutral charge of

11662-418: The photon on an outward trajectory causing it to escape the black hole, or on an inward spiral where it would eventually cross the event horizon. While light can still escape from the photon sphere, any light that crosses the photon sphere on an inbound trajectory will be captured by the black hole. Hence any light that reaches an outside observer from the photon sphere must have been emitted by objects between

11781-399: The photon sphere and the event horizon. For a Kerr black hole the radius of the photon sphere depends on the spin parameter and on the details of the photon orbit, which can be prograde (the photon rotates in the same sense of the black hole spin) or retrograde. Rotating black holes are surrounded by a region of spacetime in which it is impossible to stand still, called the ergosphere. This

11900-458: The presence of a mass deforms spacetime in such a way that the paths taken by particles bend towards the mass. At the event horizon of a black hole, this deformation becomes so strong that there are no paths that lead away from the black hole. To a distant observer, clocks near a black hole would appear to tick more slowly than those farther away from the black hole. Due to this effect, known as gravitational time dilation , an object falling into

12019-414: The same values for these properties, or parameters, are indistinguishable from one another. The degree to which the conjecture is true for real black holes under the laws of modern physics is currently an unsolved problem. These properties are special because they are visible from outside a black hole. For example, a charged black hole repels other like charges just like any other charged object. Similarly,

12138-478: The shape of the object or distribution of charge on it is evenly distributed along the horizon of the black hole, and is lost to outside observers. The behaviour of the horizon in this situation is a dissipative system that is closely analogous to that of a conductive stretchy membrane with friction and electrical resistance —the membrane paradigm . This is different from other field theories such as electromagnetism, which do not have any friction or resistivity at

12257-406: The singularities would not appear in generic situations. This view was held in particular by Vladimir Belinsky , Isaak Khalatnikov , and Evgeny Lifshitz , who tried to prove that no singularities appear in generic solutions. However, in the late 1960s Roger Penrose and Stephen Hawking used global techniques to prove that singularities appear generically. For this work, Penrose received half of

12376-506: The singularity disappeared after a change of coordinates. In 1933, Georges Lemaître realised that this meant the singularity at the Schwarzschild radius was a non-physical coordinate singularity . Arthur Eddington commented on the possibility of a star with mass compressed to the Schwarzschild radius in a 1926 book, noting that Einstein's theory allows us to rule out overly large densities for visible stars like Betelgeuse because "a star of 250 million km radius could not possibly have so high

12495-514: The star, leaving us outside (i.e., nowhere)." In 1931, Subrahmanyan Chandrasekhar calculated, using special relativity, that a non-rotating body of electron-degenerate matter above a certain limiting mass (now called the Chandrasekhar limit at 1.4  M ☉ ) has no stable solutions. His arguments were opposed by many of his contemporaries like Eddington and Lev Landau , who argued that some yet unknown mechanism would stop

12614-436: The star. Rotation, however, is expected to be a universal feature of compact astrophysical objects. The black-hole candidate binary X-ray source GRS 1915+105 appears to have an angular momentum near the maximum allowed value. That uncharged limit is allowing definition of a dimensionless spin parameter such that Black holes are commonly classified according to their mass, independent of angular momentum, J . The size of

12733-428: The surface of the star frozen in time at the instant where its collapse takes it to the Schwarzschild radius. Also in 1939, Einstein attempted to prove that black holes were impossible in his publication "On a Stationary System with Spherical Symmetry Consisting of Many Gravitating Masses", using his theory of general relativity to defend his argument. Months later, Oppenheimer and his student Hartland Snyder provided

12852-432: The term for its brevity and "advertising value", and it quickly caught on, leading some to credit Wheeler with coining the phrase. The no-hair theorem postulates that, once it achieves a stable condition after formation, a black hole has only three independent physical properties: mass, electric charge, and angular momentum; the black hole is otherwise featureless. If the conjecture is true, any two black holes that share

12971-521: The total mass inside a sphere containing a black hole can be found by using the gravitational analogue of Gauss's law (through the ADM mass ), far away from the black hole. Likewise, the angular momentum (or spin) can be measured from far away using frame dragging by the gravitomagnetic field , through for example the Lense–Thirring effect . When an object falls into a black hole, any information about

13090-436: The usual speed of light. Michell correctly noted that such supermassive but non-radiating bodies might be detectable through their gravitational effects on nearby visible bodies. Scholars of the time were initially excited by the proposal that giant but invisible 'dark stars' might be hiding in plain view, but enthusiasm dampened when the wavelike nature of light became apparent in the early nineteenth century, as if light were

13209-484: The work of Werner Israel , Brandon Carter , and David Robinson the no-hair theorem emerged, stating that a stationary black hole solution is completely described by the three parameters of the Kerr–Newman metric : mass , angular momentum , and electric charge. At first, it was suspected that the strange features of the black hole solutions were pathological artefacts from the symmetry conditions imposed, and that

13328-542: Was designated Menkib al Jauza al Aisr , which was translated into Latin as Humerus Sinister Gigantis (The Left Shoulder of the Giant). The Wardaman people of northern Australia know Bellatrix as Banjan , the sparkling pigment used in ceremonies conducted by Rigel the Red Kangaroo Leader in a songline when Orion is high in the sky. The other stars of Orion are his ceremonial tools and entourage. Betelgeuse

13447-413: Was free to develop on its own, there is no reason to suppose that the speech was uniform either diachronically or geographically. On the contrary, Romanised European populations developed their own dialects of the language, which eventually led to the differentiation of Romance languages . Late Latin is a kind of written Latin used in the 3rd to 6th centuries. This began to diverge from Classical forms at

13566-483: Was likely to intervene and stop at least some stars from collapsing to black holes. Their original calculations, based on the Pauli exclusion principle , gave it as 0.7  M ☉ . Subsequent consideration of neutron-neutron repulsion mediated by the strong force raised the estimate to approximately 1.5  M ☉ to 3.0  M ☉ . Observations of the neutron star merger GW170817 , which

13685-496: Was much more liberal in its linguistic cohesion: for example, in classical Latin sum and eram are used as auxiliary verbs in the perfect and pluperfect passive, which are compound tenses. Medieval Latin might use fui and fueram instead. Furthermore, the meanings of many words were changed and new words were introduced, often under influence from the vernacular. Identifiable individual styles of classically incorrect Latin prevail. Renaissance Latin, 1300 to 1500, and

13804-441: Was no complete separation between Italian and Latin, even into the beginning of the Renaissance . Petrarch for example saw Latin as a literary version of the spoken language. Medieval Latin is the written Latin in use during that portion of the post-classical period when no corresponding Latin vernacular existed, that is from around 700 to 1500 AD. The spoken language had developed into the various Romance languages; however, in

13923-482: Was shut down in June 2019), and Vatican Radio & Television, all of which broadcast news segments and other material in Latin. A variety of organisations, as well as informal Latin 'circuli' ('circles'), have been founded in more recent times to support the use of spoken Latin. Moreover, a number of university classics departments have begun incorporating communicative pedagogies in their Latin courses. These include

14042-461: Was urged to publish it. These results came at the beginning of the golden age of general relativity , which was marked by general relativity and black holes becoming mainstream subjects of research. This process was helped by the discovery of pulsars by Jocelyn Bell Burnell in 1967, which, by 1969, were shown to be rapidly rotating neutron stars. Until that time, neutron stars, like black holes, were regarded as just theoretical curiosities; but

14161-656: Was used in print by Life and Science News magazines in 1963, and by science journalist Ann Ewing in her article " 'Black Holes' in Space", dated 18 January 1964, which was a report on a meeting of the American Association for the Advancement of Science held in Cleveland, Ohio. In December 1967, a student reportedly suggested the phrase "black hole" at a lecture by John Wheeler ; Wheeler adopted

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