title: Superhero film

text: After the comic book boom and the success of several comic book adaptation films (including superhero films) in the 1990s, the first decade of the 21st century brought increased interest in superhero films and some of their most profitable franchises, many from Marvel Enterprises. The success of the "" TV series made 20th Century Fox licenses the film rights in 1994. After the success of "Men in Black" in 1997, Columbia Pictures licensed the film rights of "Spider-Man" in 1999. 20th Century Fox's "X-Men" (2000) became a film franchise by its surprise hit, and M. Night Shyamalan's "Unbreakable" (2000) also succeeded and added an element of more urban naturalism. Later, one of the largest blockbusters of all time was released with Sam Raimi's "Spider-Man" (2002). In 2004, "" was released, which was a remaining of the original series and the franchise as a whole. With high ticket and DVD sales, numerous new superhero films were released every year in the 2000s, including "" (2000), "Blade II" (2002), "Daredevil" (2003), "The League of Extraordinary Gentlemen" (2003), "Hulk" (2003), "X2: X-Men United" (2003), "" (2004), "Casshern" (2004), "Catwoman" (2004), "Hellboy" (2004), "The Punisher" (2004), the semi-animated "Sky Captain and the World of Tomorrow" (2004), "Spider-Man 2" (2004), "Elektra" (2005), "Constantine" (2005), "Fantastic Four" (2005), Malaysia's "Cicak Man" (2006), India's "Krrish" (2006), Thailand's "Mercury Man" (2006), "" (2006), "" (2007), "Ghost Rider" (2007), Chile's "Mirageman" (2007), "Spider-Man 3" (2007), "TMNT" (2007), "Drona" (2008) and "" (2008).


title: Superhero film

text: Brad Bird's "The Incredibles" (2004) for Pixar was a critically acclaimed computer-animated superhero film aimed towards families. Other hybrids include "Sky High" (2005) and "Zoom" (2006) which were fusions of superhero and family film, as well as "My Super Ex-Girlfriend" (2006) a combination of superhero and romantic comedy.


title: Superhero film

text: Some series from the current and previous decades were re-released, such as "" (2006). Other series discarded the continuities of previously released films and began a reboot, most notably Christopher Nolan's "Batman Begins" (2005), Louis Leterrier's "The Incredible Hulk" (2008) and Lexi Alexander's "" (2008). Bryan Singer's "Superman Returns" (2006) stands out in that it is a sequel to the first two "Superman" films, yet also a reboot of the third and fourth films. The "Batman Begins" sequel "The Dark Knight" (2008) received eight nominations at the Academy Awards with two wins for Best Sound Editing and Best Supporting Actor for Heath Ledger's portrayal of The Joker.


title: Superhero film

text: In 2008, "Iron Man" was released, setting the stage for the Marvel Cinematic Universe. The likes of 2009's "Watchmen" and "" would then close out the decade. The 2010s generally continued the box-office success of superhero films seen in the 2000s, and it took the subgenre's success and ubiquity to new heights. In 2010, Matthew Vaughn's adaptation of "Kick-Ass" was released, followed by "Iron Man 2" a month later. 2011 releases included "The Green Hornet" (2011), "Green Lantern" (2011), and "" (2011). Following references to the "Avengers Initiative" in the "Iron Man" films and "The Incredible Hulk", Marvel released "Thor" on May 6, 2011, followed by "" on July 22, 2011.


title: Superhero film

text: Although the film "" was released on February 17, 2012, to little audience interest, superhero films dominated that year's lucrative summer film market with three superhero films occupying the top three positions of the box office chart. This includes the May 2012 release of "Marvel's The Avengers", which broke the box office record as the highest-grossing superhero film of all time. The next Batman film from Christopher Nolan, "The Dark Knight Rises", is the sequel to Christopher Nolan's film "The Dark Knight", and was released on July 20, 2012, in the second position while the third was occupied by reboot of the "Spider-Man" franchise, "The Amazing Spider-Man", directed by Marc Webb and produced for Columbia Pictures.


title: Superhero film

text: A "Superman Returns" sequel was planned for 2009 but was delayed and later scrapped in favor of the reboot, "Man of Steel" (2013).


title: Superhero film

text: In 2008, there were reports that DC Comics planned to release "Green Arrow: Escape from Super Max". Other intended releases from Marvel included several new "X-Men" films, "Silver Surfer", "Ant-Man", and movies based on DC superheroes such as Wonder Woman and the Flash.


title: Superhero film

text: At the 2012 San Diego Comic-Con, Marvel confirmed that an "Ant-Man" film was in development, as well as a film based on 2008 comic series "Guardians of the Galaxy", which was released in August 2014. "Iron Man 3" was released in May 2013, "" in November 2013, and "" in April 2014. "The Amazing Spider-Man 2", the sequel to the 2012 reboot was also released in May 2014, which became the lowest-grossing and poorly received rated film in the "Spider-Man" film series. In 2013, a sequel to the 2009 film "X-Men Origins: Wolverine", titled "The Wolverine" was released. In 2014, "" released to critical acclaim and financial success; the film became the highest-grossing film in the "X-Men" series, and effectively rebooted the franchise.


title: Superhero film

text: In 2014, Italian filmmaker Gabriele Salvatores directed a superhero-fantasy film titled "Il Ragazzo invisible", or "The Invisible Boy", which won the Young Audience Award at the 2015 European Film Awards.


title: Superhero film

text: An "Avengers" sequel, titled "", was released in May 2015. Following the success of the Marvel Cinematic Universe, rival DC Comics also planned to make and produce their own shared film universe called the DC Extended Universe, which began with the release of "Man of Steel"; a sequel titled "" was scheduled for release in May 2016, though it was later moved up to March 2016. Nickelodeon's 2015 film "" features the main characters transforming into superheroes. 20th Century Fox rebooted the "Fantastic Four" series and released "Fantastic Four" in August 2015.


title: Superhero film

text: On March 9, 2015, publishing house Valiant Comics reached an unprecedented nine-figure deal with Chinese company DMG Entertainment to produce their own series of superhero movies, set in their own cinematic universe. The series will be co-produced by Sony Pictures and will start with a movie adaptation of "Bloodshot" for a 2016 release, followed by "Harbinger", both movies receiving a sequel and ending in a crossover movie based on the "Harbinger Wars" arc from the comic books.


title: Superhero film

text: In 2015, Italian filmmaker directed a superhero film, titled "They Call Me Jeeg" starring Claudio Santamaria. Its original title is "Lo chiamavano Jeeg Robot", from the Italian name of the anime and manga series "Steel Jeeg". It was released in Italy on February 25, 2016.


title: Superhero film

text: In 2016, the eighth installment in the "X-Men" series "Deadpool" was released in February, which went on to become the highest-grossing R-rated film of all time when unadjusted for inflation, and the highest-grossing film of the series. The ninth installment, "", also released. Warner Bros. released "" in March, which is the first film to feature both Batman and Superman, also released. This film performed moderately well at the box office but received poor reviews. "Suicide Squad" in August, which features a team of anti-hero/supervillains, both of which take place in the DC Extended Universe. Marvel Studios, meanwhile, in May released "", in which the Avengers splits into two opposing factions, and "Doctor Strange", which recounts the superheroic origin of Stephen Strange, in November, both of which take place in the Marvel Cinematic Universe. In October, based on the eponymous toy line by Mattel, "Max Steel" was released.


title: Superhero film

text: January 2017 saw the release of M. Night Shyamalan's "Split", which served as a standalone sequel to "Unbreakable". The first Finnish superhero film, "Rendel: Dark Vengeance", was released in September 2017 and it won the Best Action Movie award at the Erratum Film Festival in Mexico. "Power Rangers", a movie reboot of the TV series, was released in March, with Lionsgate planning a seven-film franchise, but was a commercial disappointment. By contrast, the film "Logan", which was Hugh Jackman and Patrick Stewart's last appearances as their characters in the "X-Men" film series, proved to be a major critical and commercial success. This film was the first ever canon X-Men movie to be rated R as normally they were PG-13 and became the first superhero movie to receive an Academy Award for Best Adapted Screenplay. In the summer movie season, "Guardians of the Galaxy Vol. 2", "Wonder Woman" and "" confirmed the superhero film dominance of the mainstream movie market. That dominance continued into the fall with the success of "", but Warner Bros.' attempt to consummate its attempt to have its own shared universe media franchise, the DC Extended Universe, with "Justice League" as it was critical and financial disappointment.


title: Superhero film

text: In 2018, Marvel Studios released "Black Panther" on February 16, featuring the solo film adaptation of the first mainstream African-American superhero, the Black Panther. It was commercial and critical success in the Marvel Cinematic Universe franchise. Furthermore, it became the first superhero film to be nominated for the Academy Award for Best Picture.


title: Superhero film

text: This MCU project was soon followed up by "", released on April 27, 2018, which earned both critical acclaim and worldwide financial success earning an excess of $2 billion. Soon after, 20th Century Fox released "Deadpool 2" on May 18, 2018 In addition, "Incredibles 2", the long-awaited sequel for the Academy Award-winning animated film "The Incredibles", had its wide release on June 15, 2018, met with considerable critical acclaim and earned $182.68 million on its premiere weekend. The next superhero film in the Marvel Universe "Ant-Man and the Wasp" was released on July 6, with competing studios declining to release major films on American Independence Day in the face of the reliably popular film franchise.


title: Superhero film

text: The anti-hero film "Venom" based on the comic book character was released on October 5, 2018, to poor reviews, but great box-office success. In December 2018 Warner Bros. released "Aquaman", a film about the DC Comics superhero of the same name, which became the DCEU's most successful film in the box office as it grossed $1.148 billion worldwide.


title: Superhero film

text: 2019 began with M. Night Shyamalan's "Glass", the culmination of "Unbreakable" and "Split", in January. In March, the MCU's "Captain Marvel" overcame online hostility, in part because of star Brie Larson's comments about lack of diversity in the film and film criticism industries, to become the next film in the franchise to earn over $1 billion worldwide amid largely positive reviews. Later in April, the DCEU's "Shazam!", featuring the lead character who was previously known as Captain Marvel himself, had decent box office success for its relatively low budget, which has been seen as further evidence of the revitalization of the Warner Bros. media franchise. That same month, "" ended the Infinity Saga with widespread acclaim and broke numerous box office records and became the fastest film to exceed $1 billion worldwide, doing so in five days. This film became the fastest to hit $1 billion. "Avengers: Endgame" become the highest-grossing film of all time, surpassing James Cameron's "Avatar", for over a year, before the latter retook its place.


title: Superhero film

text: By contrast, the June X-Men film "Dark Phoenix" performed poorly upon release, along with poor critical reception. In addition, it was observed that there was noticeable fan indifference for a concluding film series of a property that would be put in the complete control of Marvel Studios producer, Kevin Feige, along with the Fantastic Four, for integration into the Marvel Cinematic Universe franchise in due time considering Disney's acquisition of 20th Century Fox. In July 2019, Phase 3 of the Marvel Cinematic Universe was concluded with the Sony film, "" which was released to critical and commercial success.


title: Superhero film

text: Kevin Feige announced the lineup of of the MCU in July 2019, which includes feature films as well as television series for the streaming service Disney+. The first release was in Phase Four was originally scheduled to be the film "Black Widow", but it was delayed due to the COVID-19 pandemic, resulting in the Disney+ series "WandaVision" premiering first instead.


title: Superhero film

text: In August 2019, Joko Anwar's "Gundala" was released in Indonesia. It was screened at the Toronto International Film Festival later in September and is set to be the first entry in the Bumilangit Cinematic Universe (BCU) film series based on characters of comic books published by Bumilangit. The second and third films in the series, "Sri Asih" and "Patriot Taruna: Virgo and the Sparklings", were announced for a 2020 release but were pushed back to 2021 as production was significantly delayed by the COVID-19 pandemic. The production company's strategy of announcing films in volumes with a team-up film as the climax has led to the media dubbing it the "Indonesian equivalent to the MCU and DCEU".


title: Superhero film

text: In March 2021, the director's cut of DC's "Justice League" from Zack Snyder was released. The theatrical version of the film had been finished by Joss Whedon, after Snyder quit as a result of his daughter having committed suicide earlier during production. The director's cut was titled "Zack Snyder's Justice League" and was released exclusively on the streaming service HBO Max.


title: Superhero film

text: "The Suicide Squad" was released in August but was a box office disappointment despite receiving positive reviews. The underperformance was blamed on the continued disruption of cinema during the pandemic (particularly the delta variant) and confusion from the general audience on whether the film was a sequel, reboot or remake. Meanwhile, Marvel's "Shang-Chi and the Legend of the Ten Rings" broke Labor Day records, while similar successes were seen in the Sony's Spider-Man Universe (SSU) film "". Despite middling reviews and the first rotten rating for a Marvel Cinematic Universe film, Eternals opened to a moderate success at the box office.


title: Superhero film

text: "" released on December 17, 2021, and became the highest-grossing film of 2021, the sixth highest-grossing film of all time, the third-highest-grossing film in the United States and Canada, the highest grossing "Spider-Man" film, and the highest-grossing film produced by Sony. It also became the first film to gross over $1 billion since "" largely due to the COVID-19 pandemic, as well as the highest-grossing film not to be released in China (one of the world's biggest box office markets).


title: Superhero film

text: In 2022, Warner Bros released The Batman, a reboot for the Batman film series, and unconnected to the DC Extended Universe. It was a critical and commercial hit, with particular praise for the film being a 'grounded detective story,' Matt Reeves direction and Robert Pattinson's performance as the titular hero. It went on to become the second biggest pandemic debut, after . Morbius, starring Jared Leto and based on the Spider-Man villain of the same name debuted that April as another chapter in "Sony's Spider-Man Universe". The film was critically panned and a box-office bomb. Variety reported that whilst the initial opening was hopeful for "Morbius", 'The character is not nearly as recognizable to general audiences as Spider-Man, Batman or Venom, nor is the film clearly connected to a larger story like "Eternals" or "Shang-Chi and the Legend of the Ten Rings." Thus, "Morbius" wasn't expected to match the receipts for recent comic book tentpoles based on those characters.' Scott Mendelson further stated that Sony seemed to rely on the film's 'connection to the Spider-Man universe, the success of Venom and a misguided assumption that audiences were interested in villain movies.


title: Superhero film

text: In May, Sam Raimi returned to the superhero genre with "Doctor Strange in the Multiverse of Madness". The film was met with mixed-to-positive reviews and earned $187million on its opening weekend, becoming the eleventh-best domestic debut of all time, the best summer debut for a Disney release during the pandemic, and Raimi's best opening. In its second weekend, the film earned $61 million, becoming one of the MCU's biggest second-weekend box office drops. The 67% decline was attributed by "Deadline Hollywood" to the "bad word of mouth" on the film and its CinemaScore grade, while Intelligence saw more than 17% downsize of available seats for the film, resulting in a lessen showtimes which also led to the decline. In its third weekend, the film earned $31.6million, contributing to the 800-million-dollar mark at the box office to become Hollywood's second-highest-grossing film released during the pandemic behind "No Way Home". The film earned $16.4million in its fourth weekend, contributing to the total box office that helped it to become the highest-grossing film of 2022 previously held by "The Batman". As of June 2022, the film stands as the 11th highest-grossing of the MCU worldwide.


title: Superhero film

text: Outside of live-action, animated superhero films have also achieved critical and financial success. Nearly all animated superhero films are direct-to-video though there are a countless number of these films creating different events in them from their live-action counterparts. "" was released theatrically and was a critical success (though a box-office failure). In 1968, "VIP my Brother Superman" was released, directed by Italian animator Bruno Bozzetto; it is a parody of superheroes and enjoyed great success. In 2004, Pixar released "The Incredibles", about a retired superhero couple and their children, which did extremely well both critically and financially and went on to win the Academy Award for Best Animated Feature. In 2010 DreamWorks Animation released "Megamind" to middling success. In 2014, Walt Disney Animation Studios released an adaptation of the Marvel Comics superhero team "Big Hero 6". The same year, Warner Bros. released "The Lego Movie", which had Batman and other DC Comics superheroes in major and supporting roles. A significant box-office success, it was followed in 2017 by "The Lego Batman Movie", as well as DreamWorks Animation's "".


title: Superhero film

text: In 2018, three theatrical animated superhero films were released to considerable critical and commercial success: Pixar's "Incredibles 2", Warner Bros.'s "Teen Titans Go! To the Movies", and Sony Pictures Animation's "". Furthermore, the latter of the three swept that year's major film awards for animated features, including the Academy Award.


title: Superhero film

text: As superhero film production increased during the latter end of the 2010s, the genre's contribution to cinema was questioned. Martin Scorsese, in an interview with Empire magazine, commented that "as well made as they are, with actors doing the best they can under the circumstances, is theme parks. It isn't the cinema of human beings trying to convey emotional, psychological experiences to another human being." He stated that the Marvel films were not "cinema". He later clarified his opinion as being worried about studios' overreliance, believing that in "many places around this country and the world, franchise films are now your primary choice if you want to see something on the big screen. It’s a perilous time in film exhibition, and there are fewer independent theaters than ever." Criticism of Marvel Studios' films continued with Jennifer Aniston stating that Marvel movies are "diminishing" and believed that there should be a “resurgence” of “the era of Meg Ryan.” “Let’s get the Terms of Endearment back out there. You know, Heaven Can Wait, Young Frankenstein, Blazing Saddles, Goodbye Girl.” Denis Villeneuve dismissed "too many Marvel films" being "a cut and paste of others" and Roland Emmerich stating that large blockbuster films such as the MCU and "Star Wars" films were "ruining our industry a little" since "nobody does anything original anymore". However, in March 2022, Nicolas Cage stated that “Marvel has done a really excellent job of entertaining the whole family. They put a lot of thought into it. I mean, it’s definitely had a big progression from when I was doing the first two ‘Ghost Rider’ movies. Kevin Feige, or whoever is behind that machine, has found a masterful way of weaving the stories together and interconnecting all the characters. What could be wrong with wholesome entertainment that is appealing to the parents and the children, and gives people something to look forward to?” Cage asked. “I just, I don’t see what the issue is.”


title: Superhero film

text: Some media commentators have attributed the increased popularity of superhero franchises in the new millennium to the social and political climate in Western society since the September 11, 2001 terrorist attacks, although others have argued advances in special effects technology have played a more significant role. Others have postulated that its box office dominance is in part due to its flexibility, a shared trait from its original publishing origins. Namely, the editorial realities of comic book publishing, which can have series running for decades, encouraged writers to resort to a variety of story situations so diverse from the fantastic to the relatively realistic, for so long and so often that it has become an expected element of the genre to have such adaptability. For example, with the common element being that they all feature heroes with extraordinary abilities and typically in a distinctive costume, many successful superhero films have used a plethora of genres such as horror ("Blade"), thriller ("Unbreakable"), period drama (""), space opera ("Guardians of the Galaxy"), family film ("The Incredibles"), teen film (""), heist film ("Ant-Man"), fantasy ("Doctor Strange"), neo-noir ("The Dark Knight"), political thriller (""), and Western ("Logan").


title: Custard

text: Custard is a variety of culinary preparations based on sweetened milk, cheese, or cream cooked with egg or egg yolk to thicken it, and sometimes also flour, corn starch, or gelatin. Depending on the recipe, custard may vary in consistency from a thin pouring sauce ("crème anglaise") to the thick pastry cream ("crème pâtissière") used to fill éclairs. The most common custards are used in custard desserts or dessert sauces and typically include sugar and vanilla; however, savory custards are also found, e.g., in quiche.


title: Custard

text: Custard is usually cooked in a double boiler (bain-marie), or heated very gently in a saucepan on a stove, though custard can also be steamed, baked in the oven with or without a water bath, or even cooked in a pressure cooker. Custard preparation is a delicate operation, because a temperature increase of 3–6 °C (5–10 °F) leads to overcooking and curdling. Generally, a fully cooked custard should not exceed 80 °C (~175 °F); it begins setting at 70 °C (~160 °F). A water bath slows heat transfer and makes it easier to remove the custard from the oven before it curdles. Adding a small amount of cornflour to the egg-sugar mixture stabilises the resulting custard, allowing it to be cooked in a single pan as well as in a double-boiler. A sous-vide water bath may be used to precisely control temperature.


title: Custard

text: Stirred custard is thickened by coagulation of egg protein, while the same gives baked custard its gel structure. The type of milk used also impacts the result. Most important to a successful stirred custard is to avoid excessive heat that will cause over-coagulation and syneresis that will result in a curdled custard.


title: Custard

text: Eggs contain the proteins necessary for the gel structure to form, and emulsifiers to maintain the structure. Egg yolk also contains enzymes like amylase, which can break down added starch. This enzyme activity contributes to the overall thinning of custard in the mouth. Egg yolk lecithin also helps to maintain the milk-egg interface. The proteins in egg whites set at 60–80 °C (140–180 °F).


title: Custard

text: Starch is sometimes added to custard to prevent premature curdling. The starch acts as a heat buffer in the mixture: as they hydrate, they absorb heat and help maintain a constant rate of heat transfer. Starches also make for a smoother texture and thicker mouth feel.


title: Custard

text: If the mixture pH is 9 or higher, the gel is too hard; if it is below 5, the gel structure has difficulty forming because protonation prevents the formation of covalent bonds.


title: Custard

text: While "custard" may refer to a wide variety of thickened dishes, technically (and in French cookery) the word "custard" ("crème" or more precisely "crème moulée", ) refers only to an egg-thickened custard.


title: Custard

text: When starch is added, the result is called "pastry cream" (, ) or confectioners' custard, made with a combination of milk or cream, egg yolks, fine sugar, flour or some other starch, and usually a flavoring such as vanilla, chocolate, or lemon. "Crème pâtissière" is a key ingredient in many French desserts, including mille-feuille (or Napoleons) and filled tarts. It is also used in Italian pastry and sometimes in Boston cream pie. The thickening of the custard is caused by the combination of egg and starch. Corn flour or flour thicken at 100 °C (212˚F) and as such many recipes instruct the pastry cream to be boiled. In a traditional custard such as a "crème anglaise", where egg is used alone as a thickener, boiling results in the over cooking and subsequent 'curdling' of the custard; however, in a pastry cream, starch prevents this. Once cooled, the amount of starch in pastry cream 'sets' the cream and requires it to be beaten or whipped before use.


title: Custard

text: When gelatin is added, it is known as "crème anglaise collée" (). When gelatin is added and whipped cream is folded in, and it sets in a mold, it is "bavarois". When starch is used alone as a thickener (without eggs), the result is a "blancmange". In the United Kingdom, "custard" has various traditional recipes some thickened principally with cornflour (cornstarch) rather than the egg component, others involving regular flour; see custard powder.


title: Custard

text: After the custard has thickened, it may be mixed with other ingredients: mixed with stiffly beaten egg whites and gelatin, it is chiboust cream; mixed with whipped cream, it is "crème légère", . Beating in softened butter produces German buttercream or crème mousseline.


title: Custard

text: A quiche is a savoury custard tart. Some kinds of timbale or vegetable loaf are made of a custard base mixed with chopped savoury ingredients. "Custard royale" is a thick custard cut into decorative shapes and used to garnish soup, stew or broth. In German, it is known as Eierstich and is used as a garnish in German Wedding Soup (Hochzeitssuppe). Chawanmushi is a Japanese savoury custard, steamed and served in a small bowl or on a saucer. Chinese steamed egg is a similar but larger savoury egg dish. Bougatsa is a Greek breakfast pastry whose sweet version consists of semolina custard filling between layers of phyllo.


title: Custard

text: Custard may also be used as a top layer in gratins, such as the South African bobotie and many Balkan versions of moussaka.


title: Custard

text: In Peru, "leche asada" ("baked milk") is custard baked in individual molds. It is considered a restaurant dish.


title: Custard

text: Cooked (set) custard is a weak gel, viscous and thixotropic; while it does become easier to stir the more it is manipulated, it does not, unlike many other thixotropic liquids, recover its lost viscosity over time. On the other hand, a suspension of uncooked imitation custard powder (starch) in water, with the proper proportions, has the opposite rheological property: it is negative thixotropic, or dilatant, allowing the demonstration of "walking on custard".


title: Custard

text: Custards baked in pastry (custard tarts) were very popular in the Middle Ages, and are the origin of the English word 'custard': the French term 'croustade' originally referred to the "crust" of a tart, and is derived from the Italian word crostata, and ultimately the Latin .


title: Custard

text: Examples include "Crustardes of flessh" and "Crustade", in the 14th century English collection "The Forme of Cury". These recipes include solid ingredients such as meat, fish, and fruit bound by the custard. Stirred custards cooked in pots are also found under the names "Creme Boylede" and "Creme boiled". Some custards especially in the Elizabethan era used marigold ("calendula") to give the custard color.


title: Custard

text: In modern times, the name 'custard' is sometimes applied to starch-thickened preparations like blancmange and Bird's Custard powder.


title: Guaifenesin

text: Guaifenesin, also known as glyceryl guaiacolate, is an expectorant medication that aids in the elimination of sputum from the respiratory tract. Chemically it is an ether of guaiacol and glycerine. It is often used in combination with other medications. It is taken by mouth.


title: Guaifenesin

text: Side effects may include dizziness, sleepiness, skin rash, and nausea. While it has not been properly studied in pregnancy, it appears to be safe. It is believed to work by making airway secretions more liquid.


title: Guaifenesin

text: Guaifenesin has been used medically since at least 1933. It is available as a generic medication and over the counter. In 2020, it was the 324th most commonly prescribed medication in the United States, with more than 800thousand prescriptions.


title: Guaifenesin

text: Guaifenesin is used to try to help with coughing up thick mucus and is sometimes combined with dextromethorphan, an antitussive (cough suppressant), such as in Mucinex DM or Robitussin DM. It is also combined with ephedrine to produce Primatene and Bronkaid tablets for symptomatic relief of asthma.


title: Guaifenesin

text: Side-effects of guaifenesin include nausea, vomiting, formation of kidney stones, diarrhea, and constipation. Nausea and vomiting can be reduced by taking guaifenesin with meals. The risk of forming kidney stones during prolonged use can be reduced by maintaining good hydration and increasing the pH of urine. Rarely, severe allergic reactions may occur, including a rash or swelling of the lips or gums, which may require urgent medical assistance. Mild dry mouth or chapped lips may also occur when taking this medication. Drinking a glass of water is recommended with each dose of guaifenesin.


title: Guaifenesin

text: Guaifenesin is thought to act as an expectorant by increasing the volume and reducing the viscosity of secretions in the trachea and bronchi. It may aid in the flow of respiratory tract secretions, allowing ciliary movement to carry the loosened secretions upward toward the pharynx. Thus, it may increase the efficiency of the cough reflex and facilitate removal of the secretions.


title: Guaifenesin

text: Guaifenesin has muscle relaxant and anticonvulsant properties and may act as an NMDA receptor antagonist.


title: Guaifenesin

text: Similar medicines derived from the guaiac tree were in use as a generic remedy by American indigenous peoples when explorers reached North America in the 16th century. The Spanish encountered guaiacum wood "when they conquered Santo Domingo; it was soon brought back to Europe, where it acquired an immense reputation in the sixteenth century as a cure for syphilis and certain other diseases..."


title: Guaifenesin

text: The 1955 edition of the "Textbook of Pharmacognosy" states: "Guaiacum has a local stimulant action which is sometimes useful in sore throat. The resin is used in chronic gout and rheumatism, whilst the wood is an ingredient in the compound concentrated solution of sarsaparilla, which was formerly much used as an alternative in syphilis."


title: Guaifenesin

text: In the US, guaifenesin was first approved by the Food and Drug Administration (FDA) in 1952. Although previously deemed "Generally Regarded as Safe" in its original approval, the drug received a New Drug Application for the extended-release version, which received approval on 12 July 2002. Because of this, the FDA then issued letters to other manufacturers of "timed-release" guaifenesin to stop marketing their unapproved versions, leaving Adams Respiratory Therapeutics in control of the market. In 2007, Adams was acquired by Reckitt Benckiser. The drug is sold over-the-counter by many companies, alone and in combination.


title: Guaifenesin

text: Guaifenesin is taken by mouth. It is available under many brand names, as either the lone active ingredient or as one part of a combination drug. Drugs combined with guaifenesin in over-the-counter preparations include the cough-suppressant dextromethorphan, analgesics such as paracetamol/acetaminophen, and decongestants such as ephedrine, pseudoephedrine, or phenylephrine.


title: Guaifenesin

text: Guaifenesin's neurological properties first became known in the late 1940s. Guaifenesin is a centrally acting muscle relaxant used routinely in large-animal veterinary surgery. Guaifenesin is used in combination with, for example, ketamine, since guaifenesin does not provide analgesia nor does it produce unconsciousness.


title: Guaifenesin

text: The guaifenesin protocol was studied as a method to treat fibromyalgia; a one-year double-blind study found that the treatment performs no better than placebo.


title: Guaifenesin

text: Guaifenesin was studied as a possible fertility medication, working by thinning and increasing the stretchability (spinnbarkeit) of the cervical mucus, during the few days before ovulation, thus facilitating sperm penetration.


title: Guaifenesin

text: Results from a 2014 study by the Virginia Commonwealth University's Department of Pediatrics indicated that guaifenesin did not have significant impact on sputum production or clearance in upper respiratory infections. This was consistent with a 2014 study involving 378 adult and adolescent participants, which indicated guaifenesin had no significant effect as either mucolytic or expectorant compared to placebo: "Although the upper respiratory quality of life improved over the course of the study in both the [guaifenesin] and placebo groups, this improvement was not accompanied by changes in sputum properties".


title: Jodhpur

text: Jodhpur (; ) is the second-largest city in the Indian state of Rajasthan and officially the second metropolitan city of the state. It was formerly the seat of the princely state of Jodhpur State. Jodhpur was historically the capital of the Kingdom of Marwar, which is now part of Rajasthan. Jodhpur is a popular tourist destination, featuring many palaces, forts, and temples, set in the stark landscape of the Thar Desert. It is popularly known as the "Blue City" among people of Rajasthan and all over India. It serves as the administrative headquarters of the Jodhpur district and Jodhpur division.


title: Jodhpur

text: The old city circles the Mehrangarh Fort and is bounded by a wall with several gates. The city has expanded greatly outside the wall, though over the past several decades. Jodhpur lies near the geographic centre of the Rajasthan state, which makes it a convenient base for travel in a region much frequented by tourists. The city featured in "The New York Times"'s "52 Places to Go in 2020".


title: Jodhpur

text: The city is also home to several educational institutions, the most prominent being All India Institute of Medical Sciences, Jodhpur, Indian Institute of Technology Jodhpur, Dr. Sampurnanand Medical College, DSRRAU Jodhpur, and National Law University, Jodhpur, and many research institutes, such as Indian Space Research Organisation, Defence Research and Development Organisation, Central Arid Zone Research Institute, Arid Forest Research Institute, and Desert Medicine Research Centre are also located in the city.


title: Jodhpur

text: The Jodhpur city was founded in 1459 by Rao Jodha, a Rajput chief of the Rathore clan. Jodha succeeded in conquering the surrounding territory and thus founded a kingdom which came to be known as Marwar. As Jodha hailed from the nearby town of Mandore, that town initially served as the capital of this state; however, Jodhpur soon took over that role, even during the lifetime of Jodha. The city was located on the strategic road linking Delhi to Gujarat. This enabled it to profit from a flourishing trade in opium, copper, silk, sandalwood, dates, and other tradeable goods.


title: Jodhpur

text: After the death of Rao Chandrasen Rathore in 1581, the kingdom annexed by the Mughal Emperor Akbar, Marwar thus became a Mughal vassal owing fealty to them while enjoying internal autonomy. Jodhpur and its people benefited from this exposure to the wider world as new styles of art and architecture made their appearance and opportunities opened up for local tradesmen to make their mark across northern India.


title: Jodhpur

text: Aurangzeb briefly sequestrated the state ("circa" 1679) after the death of Maharaja Jaswant Singh, but the prior ruler Maharaja Ajit Singh was restored to the throne by Veer Durgadas Rathore after Aurangzeb died in 1707 and a great struggle of 30 years. The Mughal empire declined gradually after 1707, but the Jodhpur court was beset by intrigue; rather than benefiting from circumstances, Marwar descended into strife and invited the intervention of the Marathas, who soon supplanted the Mughals as overlords of the region. This did not make for stability or peace, however; 50 years of wars and treaties dissipated the wealth of the state, which sought the help of the British and entered into a subsidiary alliance with them. A major revolt occurred in 1857 by some Rathore nobles of Pali led by Thakur Kushal Singh of Auwa, but the rebels were defeated by the British Army under Colonel Holmes and peace was restored.


title: Jodhpur

text: During the British Raj, the state of Jodhpur had the largest land area of any in the Rajputana. The land area of the state was its population in 1901 was 44,73,759. It enjoyed an estimated revenue of £3,529,000. Its merchants, the Marwaris, flourished and came to occupy a position of dominance in trade across India.


title: Jodhpur

text: In 1947, when India became independent, the state merged into the union and Jodhpur became the second-largest city of Rajasthan. At the time of division, the ruler of Jodhpur, Hanwant Singh, did not want to join India, but finally, due to the effective persuasion of Vallabhbhai Patel at the time, the state of Jodhpur was included in the Indian Republic. Later after the State Reorganisation Act, 1956, it was included within the state of Rajasthan.


title: Jodhpur

text: As per provisional reports of Census India, Jodhpur had a population of 1,033,918 in 2011, consisting of approximately 52.62 % males and approximately 47.38 % females. The average literacy rate is 80.56 percent, approximately 88.42 percent for males and 73.93 percent for females. Approximately 12.24 percent of the population is under six years of age. Jodhpur city is governed by a Municipal Corporation which comes under Jodhpur Urban Agglomeration. The Jodhpur Urban/Metropolitan area includes Jodhpur, Kuri Bhagtasani, Mandore Industrial Area, Nandri, Pal Village and Sangariya. Its urban/metropolitan population is 1,137,815 of which 599,332 are males and 538,483 are females. With the inclusion of 395 villages in Jodhpur city in the month of February 2021 by JoDA, the new population count for the city is 2,330,000 and is expected to grow by 33.04% over the next decade. In the year 2031 population of Jodhpur city is expected to be more than 3.1 million. The population of Jodhpur city after expansion of city borders is 2,330,000.


title: Jodhpur

text: Jodhpur has a hot arid climate (Köppen "BWh"), just short of a hot semi-arid climate (Köppen "BSh") due to its very high potential evapotranspiration. Although the average rainfall is around , which falls mostly from June to September, it fluctuates greatly. In the famine year of 1899, Jodhpur received only , but in the flood year of 1917, it received as much as . Jojari river, a tributary of Luni River, flows from Banad to Salawas in Jodhpur Urban Area. A Riverfront project is approved and is in Planning for this river for 35 km length coming inside Jodhpur Urban Area which is under Nammi Ganga Project of Ministry of Jal Shakti from January 2021, earlier this project was under Jodhpur Development Authority. Pin Code of Jodhpur is 342001 which comes under Jodhpur postal division (Jodhpur Region).


title: Jodhpur

text: Temperatures are extreme from March to October, except when the monsoonal rain produces thick clouds to lower it slightly. In April, May, and June, high temperatures routinely exceed 40 °C. During the monsoon season, average temperatures decrease slightly, but the city's generally low humidity rises, which adds to the perception of the heat.


title: Jodhpur

text: Jodhpur's contributes $4 billion (approx) to Rajasthan's economy through different Industries. Jodhpur is the Handicraft Hub of India of $200 million industry. Tourism comes next where Jodhpur is one of the most popular tourist destination through many portals with top heritage hotels of India.


title: Jodhpur

text: Jodhpur also has the largest Education Industry in western Rajasthan with top Coaching institutes of IIT-JEE, NEET and Civil Service Exams.


title: Jodhpur

text: The upcoming 9 MMTPA Refinery and Petrochemical complex to be set up by Hindustan Petroleum Corporation Limited (HPCL) in Pachpadra, Barmer district will transform the industrial scene of the city drastically. Pachpadra lies just 60 kilometres from the industrial area of Boranada in Jodhpur. Around 120 by-products that are produced by the refinery are going to provide huge opportunities for new industries to be set up in and around Jodhpur.


title: Jodhpur

text: India's most ambitious industrial development project, the over US$100 billion Delhi-Mumbai Industrial Corridor Project is also going to impact the industrial scenario in Jodhpur in a big way. Marwar Junction which is located about 100 kilometres from Jodhpur will be one of the nine freight loading points along the DMIC route. Jodhpur and Pali districts fall under the region that is going to be developed as a manufacturing hub for the DMIC.


title: Jodhpur

text: Jodhpur is a significant city of western Rajasthan and lies about 250 km from the border with Pakistan. This location makes it a key base for the Indian Army, Indian Air Force (IAF), and Border Security Force. Jodhpur's South Western Air Command is one of Asia's largest and one of the most critical and strategically located airbases of the IAF (The Jodhpur Airport played the crucial role during the Indo-Pakistani wars of 1965 and 1971) deployed fighter jets and advanced light helicopters.


title: Jodhpur

text: Jodhpur has culturally been known by the name of "Jodhana" by the locals. The city is famous for its food and its popularity can be judged by the fact that one can find sweet shops named "Jodhpur Sweets" in many cities throughout India. Being at the onshore of Thar Desert, life has been influenced by ways of select nomadic tribes (so-called "gypsy" groups – "Banjara" in Hindi – have settled in some parts of the city). Jodhpur has distinct cultural identity through its food and is famous for its Mirchi Bada and Mawa Kachori.


title: Jodhpur

text: Jodhpur's most notable attractions are Mehrangarh Fort which overlooks upon the city, the blue bylanes of the old city are also an attraction, Umaid Bhawan Palace, Jaswant Thada, and the Ghanta Ghar, or Clock Tower. Tourists are also within proximity to Mandore Garden, Kaylana Lake and Garden, Balsamand Lake, Machia Biological Park, Rao Jodha Desert Rock Park, Ratanada Ganesh Temple, Toorji Ka Jhalra, Sardar Samand Lake and Palace, Masooria Hills, Veer Durgadas Smarak (monument, park, and museum), Surpura Dam and Bhim Bhadak Cave. Other attractions of people are at markets of food, antique items, traditional clothes and traditional shoes (also called "Jodhpuri Mojari") held in Jodhpur. Mahamandira, a temple consecrated to Sri Jalandharnath, is known for its murals showing ascetics in yoga poses and murals bearing inscriptional records of the dignitaries visiting the shrine which includes Charanas, nobles, and the Rajas.


title: Jodhpur

text: The city is famous for its charming locations and is often featured in various films, advertisements, music videos, and soaps. The historic buildings and landscapes of the city were featured in a number of movies, including "The Dark Knight Rises" directed by Christopher Nolan; Baadshaho starring Ajay Devgn and Emraan Hashmi, "The Darjeeling Limited" starring Owen Wilson, Adrien Brody, and Jason Schwartzman; "The Fall" directed by Tarsem Singh; "Hum Saath-Saath Hain" directed by Sooraj Barjatya; "Veer" directed by Anil Sharma; "Shuddh Desi Romance" directed by Maneesh Sharma; "I" directed by S. Shankar, "Kung Fu Yoga" starring Jackie Chan, Sonu Sood, and Disha Patani; "Loafer" starring Varun Tej and Disha Patani; "Supreme" starring Sai Dharam Tej and Rashi Khanna; and "Airlift" featuring Akshay Kumar and Nimrat Kaur. Many foreign-language films and series have also been shot in Jodhpur, such as "Buddies in India", which was produced in Mandarin and was launched in China in 2017 featuring some Indian actors, and even the songs were in Hindi.


title: Jodhpur

text: A number of dishes from Indian cuisine originated in Jodhpur. The city savours a number of food items, but the specialities of the city are Pyaaj Kachori, Mirchi Bada and Mawa Kachori.


title: Jodhpur

text: Major research institutes and organizations have been established in the city for promoting research:


title: Jodhpur

text: Rajasthan High Court is the High Court of the state of Rajasthan. It was established on 21 June 1949 under the Rajasthan High Court Ordinance, 1949.


title: Jodhpur

text: The High Court of Rajasthan was founded in 1949 in Jodhpur and was inaugurated by the Rajpramukh, Maharaja Sawai Man Singh on 29 August 1949. The first Chief Justice was Kamala Kant Verma and the current Chief Justice of the Rajasthan High Court is the Honorable Justice Indrajit mohanty. A bench was formed at Jaipur which was dissolved in 1958 and was again formed on 31 January 1977. Currently, there are forty sanctioned judges.


title: Jodhpur

text: Till 2020, the city was administered by a single municipal body, Jodhpur Nagar Nigam with a mayor. In 2019, the Rajasthan government decided to form two municipal corporation in Jaipur, Jodhpur and Kota for better administration. For administrative purposes, the city is divided into wards, from which the members of the corporation council are elected for five years. The municipal corporation has elected members known as councilors, or "parshad" in Hindi, representing their respective wards (geographical units of the city). The ward members are elected by direct voting by electorate for a period of 5 years. In addition to these directly elected members, the corporation has four "ex-officio" members (one member of parliament, three members of legislative assembly, namely Sardarpura, Soorsagar, City), and three nominated members. Currently, the city has two civic bodies – Jodhpur North and Jodhpur South each headed by a mayor. Each municipal corporation has 80 wards, making a total of 160 wards in the city. The Jodhpur Development Authority (JDA) executes and supervises plans and schemes for the development of the urban region.


title: Jodhpur

text: The city has well-established rail, road, and air networks connecting it to other major cities of the country.


title: Jodhpur

text: For experiencing the true magnificence and royal opulence of Rajasthan, luxury trains Palace on Wheels, Royal Rajasthan on Wheels, and Maharaja Express are run jointly by Rajasthan Tourism Development Corporation and Indian Railways. Jodhpur is one of the destinations of both of the trains.


title: Jodhpur

text: In 2012-13 Railway Budget,A plan for building a High Speed Rail Corridor between Delhi-Jodhpur via Jaipur and Ajmer of 591 km was introduced which later in 2020 was included in HSR by Indian Railways and Government of India and now is in Pre-Feasibility phase.


title: Jodhpur

text: In 2013, a plan to start metro train service in Jodhpur was proposed by then Rajasthan Government to decongest the city traffic. However, this proposal is still pending with the state government for its approval.


title: Jodhpur

text: But in 2021, Jodhpur Development Authority and Municipal Corporations made a Future Mobility Plan where a 35-km Metro Line is proposed from IIT Jodhpur to Jaisalmer Bypass after Year 2030. With another proposed 11 more BRTS Corridors in Jodhpur between 2021–2030 to provide public transport to the increasing population before starting Metro.


title: Jodhpur

text: Jodhpur Airport is one of the prominent airports of Rajasthan. It is primarily a military airbase with a civilian enclosure to allow for civilian air traffic. Due to Jodhpur's strategic location, this airport is regarded as one of the most important ones for the Indian Air Force.


title: Jodhpur

text: At present, direct flights from Ahmedabad, Belgaum, Bengaluru, Chennai, Delhi, Hyderabad, Indore, Kolkata and Mumbai to the city are operated by Air India Indigo, SpiceJet, Vistara and Star Air. The bill and basic formalities for the long-awaited expansion of the airport were cleared by all the concerned authorities in June 2016, clearing the way for the expansion of the airport in two phases beginning February 2016. After the expansion, morning and evening flights are expected from the city to more cities than presently available, in addition to more airlines coming to and from the city.


title: Jodhpur

text: Jodhpur is connected by road to all major cities in Rajasthan and neighboring states, such as Delhi, Ahmedabad, Surat, Ujjain, and Agra. Apart from deluxe and express bus services to cities within the state, Rajasthan Roadways provides Volvo and Mercedes Benz bus service to Delhi, Ahmedabad, Jaipur, Udaipur, and Jaisalmer. In 2016, Bus Rapid Transit System Jodhpur was launched in the city with low-floor and semi-low-floor buses plying on 6 major routes.


title: Jodhpur

text: Jodhpur is connected to the National Highway network with three national highways and to the Rajasthan State Highway network with 10 state highways.Jodhpur Ring Road is under construction encircling Jodhpur to reduce vehicular traffic.


title: Jodhpur

text: Jodhpur has two outdoor stadiums and one indoor stadium complex. Barkatullah Khan Stadium has hosted two cricket one day internationals. Maharaja Umaid Singh Stadium and Gaushala Maidan Sports Complex are also among other sports facilities.


title: Grey alien

text: Grey aliens, also referred to as Zeta Reticulans, Roswell Greys, or Grays, are purported extraterrestrial beings. They are frequent subjects of close encounters and alien abduction claims. The details of such claims vary widely, but typically Greys are described as being human-like with small bodies with smooth, grey-colored skin; enlarged, hairless heads; and large, black eyes. The Barney and Betty Hill abduction claim, which purportedly took place in New Hampshire in 1961, popularized Grey aliens. Precursor figures have been described in science fiction and similar descriptions appeared in early accounts of the 1948 Aztec UFO Hoax and later accounts of the 1947 Roswell UFO incident.


title: Grey alien

text: The Grey alien has emerged as an archetypal image of an intelligent non-human creature and extraterrestrial life in general, as well as an iconic trope of popular culture in the age of space exploration.


title: Grey alien

text: Greys are typically depicted as grey-skinned, diminutive humanoid beings that possess reduced forms of, or completely lack, external human body parts such as noses, ears, or sex organs. Their bodies are usually depicted as being elongated, having a small chest, and lacking in muscular definition and visible skeletal structure. Their legs are depicted as being shorter and jointed differently from humans with limbs proportionally different from a human.


title: Grey alien

text: Greys are depicted as having unusually large heads in proportion to their bodies with no hair on the body, and no noticeable outer ears or noses, sometimes with small openings or orifices for ears, nostrils, and mouths. In drawings, Greys are almost always shown with very large, opaque, black eyes. They are frequently described as shorter than average adult humans.


title: Grey alien

text: The association between Grey aliens and Zeta Reticuli originated with the interpretation of a map drawn by Betty Hill by a schoolteacher named Marjorie Fish sometime in 1969. Betty Hill, under hypnosis, had claimed to have been shown a map that displayed the aliens' home system and nearby stars. Upon learning of this, Fish attempted to create a model from a drawing produced by Hill, eventually determining that the stars marked as the aliens' home were Zeta Reticuli, a binary star system.


title: Grey alien

text: The origins of the Grey alien may go back to the late 19th century. In 1891, the novel "Meda: A Tale of the Future" was published by Kenneth Folingsby, in which the narrator encountered small, grey-skinned aliens with balloon-shaped heads. In 1893, H. G. Wells presented a description of humanity's future appearance in the article "The Man of the Year Million", describing humans as having no mouths, noses, or hair, and with large heads. In 1895, Wells also depicted the Eloi, a successor species to humanity, in similar terms in the novel "The Time Machine".


title: Grey alien

text: As early as 1917, the occultist Aleister Crowley described a meeting with a "preternatural entity" named Lam that was similar in appearance to a modern Grey. Crowley believed he had contacted the entity through a process that he called the "Amalantrah Workings," which he thought allowed humans to contact beings from outer space and across dimensions. Other occultists and ufologists, many of whom have retroactively linked Lam to later Grey encounters, have since described their own visitations from him, with one describing the being as a "cold, computer-like intelligence," and utterly beyond human comprehension.


title: Grey alien

text: In 1933, the Swedish novelist Gustav Sandgren, using the pen name Gabriel Linde, published a science fiction novel called "Den okända faran" ("The Unknown Danger"), in which he describes a race of extraterrestrials who wore clothes made of soft grey fabric and were short, with big bald heads, and large, dark, gleaming eyes. The novel, aimed at young readers, included illustrations of the imagined aliens. This description would become the template upon which the popular image of grey aliens is based.


title: Grey alien

text: The conception remained a niche one until 1965, when newspaper reports of the Betty and Barney Hill abduction made the archetype famous. The alleged abductees, Betty and Barney Hill, claimed that in 1961, humanoid alien beings with grayish skin had abducted them and taken them to a flying saucer.


title: Grey alien

text: In his 1990 article "Entirely Unpredisposed", Martin Kottmeyer suggested that Barney's memories revealed under hypnosis might have been influenced by an episode of the science-fiction television show "The Outer Limits" titled "The Bellero Shield", which was broadcast 12 days before Barney's first hypnotic session. The episode featured an extraterrestrial with large eyes, who says, "In all the universes, in all the unities beyond the universes, all who have eyes have eyes that speak." The report from the regression featured a scenario that was in some respects similar to the television show. In part, Kottmeyer wrote:


title: Grey alien

text: Carl Sagan echoed Kottmeyer's suspicions in his 1997 book, "The Demon Haunted World: Science as a Candle in the Dark", where "Invaders from Mars" was cited as another potential inspiration.


title: Grey alien

text: After the Hills' encounter, Greys would go on to become an integral part of ufology and other extraterrestrial-related folklore. This is particularly true in the case of the United States: according to journalist C. D. B. Bryan, 73% of all reported alien encounters in the United States describe Grey aliens, a significantly higher proportion than other countries.


title: Grey alien

text: During the early 1980s, Greys were linked to the alleged crash-landing of a flying saucer in Roswell, New Mexico, in 1947. A number of publications contained statements from individuals who claimed to have seen the U.S. military handling a number of unusually proportioned, bald, child-sized beings. These individuals claimed, during and after the incident, that the beings had oversized heads and slanted eyes, but scant other distinguishable facial features.


title: Grey alien

text: In 1987, novelist Whitley Strieber published the book "Communion", which, unlike his previous works, was categorized as non-fiction, and in which he describes a number of close encounters he alleges to have experienced with Greys and other extraterrestrial beings. The book became a "New York Times" bestseller, and New Line Cinema released a 1989 film adaption that starred Christopher Walken as Strieber.


title: Grey alien

text: In 1988, Christophe Dechavanne interviewed the French science-fiction writer and ufologist Jimmy Guieu during a weekly French TV "Live Show", which at the time was entitled "Ciel, mon mardi !" It was broadcast by TF1, one of the three national TV channels in France. Besides mentioning Majestic 12, Jimmy Guieu described the existence of what he called "the little greys", which later on became better known in French under the name: "les Petits-Gris". Guieu later wrote two docudramas, using as a plot the Grey aliens / Majestic-12 conspiracy theory as described by John Lear and Milton William Cooper: the series "E.B.E." (for "Extraterrestrial Biological Entity"): "E.B.E.: Alerte rouge" (first part) (1990) and "E.B.E.: L'entité noire d'Andamooka" (second part) (1991).


title: Grey alien

text: Greys have since become the subject of many conspiracy theories. Many conspiracy theorists believe that Greys represent part of a government-led disinformation or plausible deniability campaign, or that they are a product of government mind-control experiments. During the 1990s, popular culture also began to increasingly link Greys to a number of military-industrial complex and New World Order conspiracy theories.


title: Grey alien

text: In 1995, filmmaker Ray Santilli claimed to have obtained 22 reels of 16 mm film that depicted the autopsy of a "real" Grey supposedly recovered from the site of the 1947 incident in Roswell. In 2006, though, Santilli announced that the film was not original, but was instead a "reconstruction" created after the original film was found to have degraded. He maintained that a real Grey had been found and autopsied on camera in 1947, and that the footage released to the public contained a percentage of that original footage.


title: Grey alien

text: Greys are often involved in alien abduction claims. Among reports of alien encounters, Greys make up about 50% in Australia, 73% in the United States, 48% in continental Europe, and around 12% in the United Kingdom. These reports include two distinct groups of Greys that differ in height.


title: Grey alien

text: Abduction claims are often described as extremely traumatic, similar to an abduction by humans or even a sexual assault in the level of trauma and distress. The emotional impact of perceived abductions can be as great as that of combat, sexual abuse, and other traumatic events.


title: Grey alien

text: The eyes are often a focus of abduction claims, which often describe a Grey staring into the eyes of an abductee when conducting mental procedures. This staring is claimed to induce hallucinogenic states or directly provoke different emotions.


title: Grey alien

text: Neurologist Steven Novella proposes that Grey aliens are a byproduct of the human imagination, with the Greys' most distinctive features representing everything that modern humans traditionally link with intelligence. "The aliens, however, do not just appear as humans, they appear like humans with those traits we psychologically associate with intelligence."


title: Grey alien

text: In 2005, Frederick V. Malmstrom, writing in "Skeptic" magazine, volume 11, issue 4, presents his idea that Greys are actually residual memories of early childhood development. Malmstrom reconstructs the face of a Grey through transformation of a mother's face based on our best understanding of early-childhood sensation and perception. Malmstrom's study offers another alternative to the existence of Greys, the intense instinctive response many people experience when presented an image of a Grey, and the act of regression hypnosis and recovered-memory therapy in "recovering" memories of alien abduction experiences, along with their common themes.


title: Grey alien

text: According to biologist Jack Cohen, the typical image of a Grey, assuming that it would have evolved from a world with different environmental and ecological conditions from Earth, is too physiologically similar to a human to be credible as a representation of an alien.


title: Grey alien

text: Depictions of Grey aliens have gone on to appear in a number of films and television shows, supplanting the previously popular little green men. As early as 1966, for example, the superhero character Ultraman was explicitly based on them, and in 1977 they were featured in "Close Encounters of the Third Kind". Greys have also been worked into space opera and other interstellar settings: in "Babylon 5", the Greys are referred to as the "Vree", and are depicted as being allies and trade partners of 23rd-century Earth, while in the "Stargate" franchise they are called the "Asgard" and depicted as ancient astronauts.


title: Grey alien

text: During the 1990s, plotlines wherein Greys were linked to conspiracy theories became common. and "American Dad!", which features a Grey-like alien named Roger, whose backstory draws from both the Roswell incident and Area 51 conspiracy theories.


title: Grey alien

text: The 2011 film "Paul" tells the story of a Grey named Paul who attributes the Greys' frequent presence in science fiction pop culture to the US government deliberately inserting the stereotypical Grey alien image into mainstream media; this is done so that if humanity came into contact with Paul's species, no immediate shock would occur as to their appearance.


title: Eratosthenes

text: Eratosthenes of Cyrene (; ;  – ) was a Greek polymath: a mathematician, geographer, poet, astronomer, and music theorist. He was a man of learning, becoming the chief librarian at the Library of Alexandria. His work is comparable to what is now known as the study of geography, and he introduced some of the terminology still used today.


title: Eratosthenes

text: He is best known for being the first person known to calculate the circumference of the Earth, which he did by using the extensive survey results he could access in his role at the Library; his calculation was remarkably accurate. He was also the first to calculate Earth's axial tilt, which also proved to have remarkable accuracy. He created the first global projection of the world, incorporating parallels and meridians based on the available geographic knowledge of his era.


title: Eratosthenes

text: Eratosthenes was the founder of scientific chronology; he endeavoured to revise the dates of the main events of the semi-mythological Trojan War, dating the Sack of Troy to 1183 BC. In number theory, he introduced the sieve of Eratosthenes, an efficient method of identifying prime numbers.


title: Eratosthenes

text: He was a figure of influence in many fields who yearned to understand the complexities of the entire world. His devotees nicknamed him "Pentathlos" after the Olympians who were well rounded competitors, for he had proven himself to be knowledgeable in every area of learning. Yet, according to an entry in the Suda (a 10th-century encyclopedia), some critics scorned him, calling him "Beta" (the second letter of the Greek alphabet) because he always came in second in all his endeavours.


title: Eratosthenes

text: The son of Aglaos, Eratosthenes was born in 276 BC in Cyrene. Now part of modern-day Libya, Cyrene had been founded by Greeks centuries earlier and became the capital of Pentapolis (North Africa), a country of five cities: Cyrene, Arsinoe, Berenice, Ptolemias, and Apollonia. Alexander the Great conquered Cyrene in 332 BC, and following his death in 323 BC, its rule was given to one of his generals, Ptolemy I Soter, the founder of the Ptolemaic Kingdom. Under Ptolemaic rule the economy prospered, based largely on the export of horses and silphium, a plant used for rich seasoning and medicine. Cyrene became a place of cultivation, where knowledge blossomed. Like any young Greek at the time, Eratosthenes would have studied in the local gymnasium, where he would have learned physical skills and social discourse as well as reading, writing, arithmetic, poetry, and music.


title: Eratosthenes

text: Eratosthenes went to Athens to further his studies. There he was taught Stoicism by its founder, Zeno of Citium, in philosophical lectures on living a virtuous life. He then studied under Aristo of Chios, who led a more cynical school of philosophy. He also studied under the head of the Platonic Academy, who was Arcesilaus of Pitane. His interest in Plato led him to write his very first work at a scholarly level, "Platonikos", inquiring into the mathematical foundation of Plato's philosophies. Eratosthenes was a man of many perspectives and investigated the art of poetry under Callimachus. He wrote poems: one in hexameters called "Hermes", illustrating the god's life history; and another in elegiacs, called "Erigone", describing the suicide of the Athenian maiden Erigone (daughter of Icarius). He wrote "Chronographies", a text that scientifically depicted dates of importance, beginning with the Trojan War. This work was highly esteemed for its accuracy. George Syncellus was later able to preserve from "Chronographies" a list of 38 kings of the Egyptian Thebes. Eratosthenes also wrote "Olympic Victors", a chronology of the winners of the Olympic Games. It is not known when he wrote his works, but they highlighted his abilities.


title: Eratosthenes

text: These works and his great poetic abilities led the pharaoh Ptolemy III Euergetes to seek to place him as a librarian at the Library of Alexandria in the year 245 BC. Eratosthenes, then thirty years old, accepted Ptolemy's invitation and traveled to Alexandria, where he lived for the rest of his life. Within about five years he became Chief Librarian, a position that the poet Apollonius Rhodius had previously held. As head of the library Eratosthenes tutored the children of Ptolemy, including Ptolemy IV Philopator who became the fourth Ptolemaic pharaoh. He expanded the library's holdings: in Alexandria all books had to be surrendered for duplication. It was said that these were copied so accurately that it was impossible to tell if the library had returned the original or the copy.


title: Eratosthenes

text: He sought to maintain the reputation of the Library of Alexandria against competition from the Library of Pergamum. Eratosthenes created a whole section devoted to the examination of Homer, and acquired original works of great tragic dramas of Aeschylus, Sophocles and Euripides.


title: Eratosthenes

text: Eratosthenes made several important contributions to mathematics and science, and was a friend of Archimedes. Around 255 BC, he invented the armillary sphere. In "On the Circular Motions of the Celestial Bodies", Cleomedes credited him with having calculated the Earth's circumference around 240 BC, with a high precision.


title: Eratosthenes

text: Eratosthenes believed there was both good and bad in every nation and criticized Aristotle for arguing that humanity was divided into Greeks and barbarians, as well as for arguing that the Greeks should keep themselves racially pure. As he aged, he contracted ophthalmia, becoming blind around 195 BC. Losing the ability to read and to observe nature plagued and depressed him, leading him to voluntarily starve himself to death. He died in 194 BC at 82 in Alexandria.


title: Eratosthenes

text: The measurement of Earth's circumference is the most famous among the results obtained by Eratosthenes, who estimated that the meridian has a length of 252,000 stadia (39,060–40,320 km), with an error on the real value between −2.4% and +0.8% (assuming a value for the stadion between 155 and 160 metres). Eratosthenes described his arc measurement technique, in a book entitled "", which has not been preserved. However, a simplified version of the method has been preserved, as described by Cleomedes.


title: Eratosthenes

text: The simplified method works by considering two cities along the same meridian and measuring both the distance between them and the difference in angles of the shadows cast by the sun on a vertical rod (a gnomon) in each city at noon on the summer solstice. The two cities used were Alexandria and Syene (modern Aswan), and the distance between the cities was measured by professional bematists. A geometric calculation reveals that the circumference of the Earth is the distance between the two cities divided by the difference in shadow angles expressed as a fraction of one turn.


title: Eratosthenes

text: Eratosthenes now continued from his knowledge about the Earth. Using his discoveries and knowledge of its size and shape, he began to sketch it. In the Library of Alexandria he had access to various travel books, which contained various items of information and representations of the world that needed to be pieced together in some organized format. In his three-volume work "Geography" (), he described and mapped his entire known world, even dividing the Earth into five climate zones: two freezing zones around the poles, two temperate zones, and a zone encompassing the equator and the tropics. This book is the first recorded instance of many terms still in use today, including the name of the discipline geography. He placed grids of overlapping lines over the surface of the Earth. He used parallels and meridians to link together every place in the world. It was now possible to estimate one's distance from remote locations with this network over the surface of the Earth. In the "Geography" the names of over 400 cities and their locations were shown, which had never been achieved before. However, his "Geography" has been lost to history, although fragments of the work can be pieced together from other great historians like Pliny, Polybius, Strabo, and Marcianus. While this work is the earliest we can trace certain ideas, words, and concepts in the historical record, earlier contributions may have been lost to history.


title: Eratosthenes

text: According to Strabo, Eratosthenes argued against the Greek-Barbarian dichotomy. He says Alexander ignored his advisers by his regard for all people with law and government. Strabo says that Eratosthenes was wrong to claim that Alexander had disregarded the counsel of his advisers. Strabo argues it was Alexander's interpretation of their "real intent" in recognizing that "in some people there prevail the law-abiding and the political instinct, and the qualities associated with education and powers of speech".


title: Eratosthenes

text: Eratosthenes was described by the Suda Lexicon as a Πένταθλος (Pentathlos) which can be translated as "All-Rounder", for he was skilled in a variety of things: He was a true polymath. He was nicknamed Beta because he was great at many things and tried to get his hands on every bit of information but never achieved the highest rank in anything; Strabo accounts Eratosthenes as a mathematician among geographers and a geographer among mathematicians.


title: Eratosthenes

text: Eratosthenes proposed a simple algorithm for finding prime numbers. This algorithm is known in mathematics as the Sieve of Eratosthenes.


title: Eratosthenes

text: In mathematics, the sieve of Eratosthenes (Greek: κόσκινον Ἐρατοσθένους), one of a number of prime number sieves, is a simple, ancient algorithm for finding all prime numbers up to any given limit. It does so by iteratively marking as composite, "i.e.", not prime, the multiples of each prime, starting with the multiples of 2. The multiples of a given prime are generated starting from that prime, as a sequence of numbers with the same difference, equal to that prime, between consecutive numbers. This is the sieve's key distinction from using trial division to sequentially test each candidate number for divisibility by each prime.


title: Eratosthenes

text: Eratosthenes was one of the most pre-eminent scholarly figures of his time, and produced works covering a vast area of knowledge before and during his time at the Library. He wrote on many topicsgeography, mathematics, philosophy, chronology, literary criticism, grammar, poetry, and even old comedies. Unfortunately, there are no documents left of his work after the destruction of the Library of Alexandria.


title: Expansion of the universe

text: The expansion of the universe is the increase in distance between any two given gravitationally unbound parts of the observable universe with time. It is an intrinsic expansion whereby the scale of space itself changes. The universe does not expand "into" anything and does not require space to exist "outside" it. This expansion involves neither space nor objects in space "moving" in a traditional sense, but rather it is the metric (which governs the size and geometry of spacetime itself) that changes in scale. As the spatial part of the universe's spacetime metric increases in scale, objects become more distant from one another at ever-increasing speeds. To any observer in the universe, it appears that all of space is expanding, and that all but the nearest galaxies (which are bound by gravity) recede at speeds that are proportional to their distance from the observer. While objects within space cannot travel faster than light, this limitation does not apply to the effects of changes in the metric itself. Objects that recede beyond the cosmic event horizon will eventually become unobservable, as no new light from them will be capable of overcoming the universe's expansion, limiting the size of our observable universe.


title: Expansion of the universe

text: As an effect of general relativity, the expansion of the universe is different from the expansions and explosions seen in daily life. It is a property of the universe as a whole and occurs throughout the universe, rather than happening just to one part of the universe. Therefore, unlike other expansions and explosions, it cannot be observed from "outside" of it; it is believed that there is no "outside" to observe from.


title: Expansion of the universe

text: Metric expansion is a key feature of Big Bang cosmology, is modeled mathematically with the Friedmann–Lemaître–Robertson–Walker metric and is a generic property of the universe we inhabit. However, the model is valid only on large scales (roughly the scale of galaxy clusters and above), because gravity binds matter together strongly enough that metric expansion cannot be observed on a smaller scale at this time. As such, the only galaxies receding from one another as a result of metric expansion are those separated by cosmologically relevant scales larger than the length scales associated with the gravitational collapse that are possible in the age of the universe given the matter density and average expansion rate.


title: Expansion of the universe

text: According to inflation theory, during the inflationary epoch about 10 of a second after the Big Bang, the universe suddenly expanded, and its volume increased by a factor of at least 10 (an expansion of distance by a factor of at least 10 in each of the three dimensions). This would be equivalent to expanding an object 1 nanometer (10 m, about half the width of a molecule of DNA) in length to one approximately 10.6 light years (about 10 m or 62 trillion miles) long. A much slower and gradual expansion of space continued after this, until at around 9.8 billion years after the Big Bang (4 billion years ago) it began to gradually expand more quickly, and is still doing so. Physicists have postulated the existence of dark energy, appearing as a cosmological constant in the simplest gravitational models, as a way to explain this late-time acceleration. According to the simplest extrapolation of the currently favored cosmological model, the Lambda-CDM model, this acceleration becomes more dominant into the future. In June 2016, NASA and ESA scientists reported that the universe was found to be expanding 5% to 9% faster than thought earlier, based on studies using the Hubble Space Telescope.


title: Expansion of the universe

text: In 1912, Vesto Slipher discovered that light from remote galaxies was redshifted, which was later interpreted as galaxies receding from the Earth. In 1922, Alexander Friedmann used Einstein field equations to provide theoretical evidence that the universe is expanding.


title: Expansion of the universe

text: Swedish astronomer Knut Lundmark was the first person to find observational evidence for expansion in 1924. According to Ian Steer of the NASA/IPAC Extragalactic Database of Galaxy Distances, "Lundmark's extragalactic distance estimates were far more accurate than Hubble's, consistent with an expansion rate (Hubble constant) that was within 1% of the best measurements today."


title: Expansion of the universe

text: In 1927, Georges Lemaître independently reached a similar conclusion to Friedmann on a theoretical basis, and also presented observational evidence for a linear relationship between distance to galaxies and their recessional velocity. Edwin Hubble observationally confirmed Lundmark's and Lemaître's findings in 1929. Assuming the cosmological principle, these findings would imply that all galaxies are moving away from each other.


title: Expansion of the universe

text: Based on large quantities of experimental observation and theoretical work, the scientific consensus is that "space itself is expanding", and that it expanded very rapidly within the first fraction of a second after the Big Bang, approximately 13.8 billion years ago. This kind of expansion is known as "metric expansion". In mathematics and physics, a "metric" means a measure of distance, and the term implies that "the sense of distance within the universe is itself changing".


title: Expansion of the universe

text: On 13 January 1994, NASA formally announced a completion of its repairs on the main mirror of the Hubble Space Telescope allowing for sharper images and, consequently, more accurate analyses of its observations. Briefly after the repairs were made, Wendy Freedman's 1994 Key Project analyzed the recession velocity of M100 from the core of the Virgo cluster, offering a Hubble constant measurement of 80±17 km s Mpc (Mega Parsec). Later the same year, Adam Riess et al utilized an empirical method of visual band light shape curves to more finely estimate the luminosity of Type Ia supernova. This further minimized the systemic measurement errors of the Hubble constant to 67±7 km s Mpc. Reiss's measurements on the recession velocity of the nearby Virgo cluster more closely agree with subsequent and independent analyses of Cepheid variable calibrations of 1a supernovae, which estimates a Hubble Constant of 73±7km s Mpc. Within the next decade, in 2003, David Spergel's analysis of the Cosmic microwave background during the first year observations of the "Wilkinson Microwave Anisotropy Probe" satellite (WMAP) further agreed with the estimated expansion rates for local galaxies, 72±5 km s Mpc.


title: Expansion of the universe

text: The modern explanation for the metric expansion of space was proposed by physicist Alan Guth in 1979 while investigating the problem of why no magnetic monopoles are seen today. Guth found in his investigation that if the universe contained a field that has a positive-energy false vacuum state, then according to general relativity it would generate an "exponential expansion of space". It was very quickly realized that such an expansion would resolve many other long-standing problems. These problems arise from the observation that to look as it does today, the universe would have to have started from very finely tuned, or "special" initial conditions at the Big Bang. Inflation theory largely resolves these problems as well, thus making a universe like ours much more likely in the context of Big Bang theory. According to Roger Penrose, inflation does not solve the main problem it was supposed to solve, namely the incredibly low entropy (with "unlikeliness" of the state on the order of 1/10 ) of the early Universe contained in the "gravitational conformal degrees of freedom" (in contrast to fields degrees of freedom, such like the cosmic microwave background whose smoothness can be explained by inflation). Thus, he puts forward his scenario of the evolution of the Universe: conformal cyclic cosmology.


title: Expansion of the universe

text: No field responsible for cosmic inflation has been discovered. However such a field, if found in the future, would be scalar. The first similar scalar field proven to exist was only discovered in 2012–2013 and is still being researched. So it is not seen as problematic that a field responsible for cosmic inflation and the metric expansion of space has not yet been discovered.


title: Expansion of the universe

text: The proposed field and its quanta (the subatomic particles related to it) have been named "inflaton". If this field did not exist, scientists would have to propose a different explanation for all the observations that strongly suggest a metric expansion of space has occurred, and is still occurring much more slowly today.


title: Expansion of the universe

text: To understand the metric expansion of the universe, it is helpful to discuss briefly what a metric is, and how metric expansion works.


title: Expansion of the universe

text: A metric defines the concept of distance, by stating in mathematical terms how distances between two nearby points in space are measured, in terms of the coordinate system. Coordinate systems locate points in a space (of whatever number of dimensions) by assigning unique positions on a grid, known as coordinates, to each point. Latitude and longitude, and x-y graphs are common examples of coordinates. A metric is a formula that describes how a number known as "distance" is to be measured between two points.


title: Expansion of the universe

text: It may seem obvious that distance is measured by a straight line, but in many cases it is not. For example, long haul aircraft travel along a curve known as a "great circle" and not a straight line, because that is a better metric for air travel. (A straight line would go through the earth). Another example is planning a car journey, where one might want the shortest journey in terms of travel time - in that case a straight line is a poor choice of metric because the shortest distance by road is not normally a straight line, and even the path nearest to a straight line will not necessarily be the quickest. A final example is the internet, where even for nearby towns, the quickest route for data can be via major connections that go across the country and back again. In this case the metric used will be the shortest time that data takes to travel between two points on the network.


title: Expansion of the universe

text: In cosmology, we cannot use a ruler to measure metric expansion, because our ruler's internal forces easily overcome the extremely slow expansion of space, leaving the ruler intact. Also, any objects on or near earth that we might measure are being held together or pushed apart by several forces that are far larger in their effects. So even if we could measure the tiny expansion that is still happening, we would not notice the change on a small scale or in everyday life. On a large intergalactic scale, we can use other tests of distance and these "do" show that space is expanding, even if a ruler on earth could not measure it.


title: Expansion of the universe

text: The metric expansion of space is described using the mathematics of metric tensors. The coordinate system we use is called "comoving coordinates", a type of coordinate system that takes account of time as well as space and the speed of light, and allows us to incorporate the effects of both general and special relativity.


title: Expansion of the universe

text: For example, consider the measurement of distance between two places on the surface of the Earth. This is a simple, familiar example of spherical geometry. Because the surface of the Earth is two-dimensional, points on the surface of the Earth can be specified by two coordinates – for example, the latitude and longitude. Specification of a metric requires that one first specify the coordinates used. In our simple example of the surface of the Earth, we could choose any kind of coordinate system we wish, for example latitude and longitude, or X-Y-Z Cartesian coordinates. Once we have chosen a specific coordinate system, the numerical values of the coordinates of any two points are uniquely determined, and based upon the properties of the space being discussed, the appropriate metric is mathematically established too. On the curved surface of the Earth, we can see this effect in long-haul airline flights where the distance between two points is measured based upon a great circle, rather than the straight line one might plot on a two-dimensional map of the Earth's surface. In general, such shortest-distance paths are called "geodesics". In Euclidean geometry, the geodesic is a straight line, while in non-Euclidean geometry such as on the Earth's surface, this is not the case. Indeed, even the shortest-distance great circle path is always longer than the Euclidean straight line path which passes through the interior of the Earth. The difference between the straight line path and the shortest-distance great circle path is due to the curvature of the Earth's surface. While there is always an effect due to this curvature, at short distances the effect is small enough to be unnoticeable.


title: Expansion of the universe

text: On plane maps, great circles of the Earth are mostly not shown as straight lines. Indeed, there is a seldom-used map projection, namely the gnomonic projection, where all great circles are shown as straight lines, but in this projection, the distance scale varies very much in different areas. There is no map projection in which the distance between any two points on Earth, measured along the great circle geodesics, is directly proportional to their distance on the map; such accuracy is possible only with a globe.


title: Expansion of the universe

text: In differential geometry, the backbone mathematics for general relativity, a metric tensor can be defined that precisely characterizes the space being described by explaining the way distances should be measured in every possible direction. General relativity necessarily invokes a metric in four dimensions (one of time, three of space) because, in general, different reference frames will experience different intervals of time and space depending on the inertial frame. This means that the metric tensor in general relativity relates precisely how two events in spacetime are separated.


title: Expansion of the universe

text: A metric expansion occurs when the metric tensor changes with time (and, specifically, whenever the spatial part of the metric gets larger as time goes forward). This kind of expansion is different from all kinds of expansions and explosions commonly seen in nature in no small part because times and distances are not the same in all reference frames, but are instead subject to change. A useful visualization is,rather than imagining objects in a fixed "space" moving apart into "emptiness", instead imagine space itself growing between all objects, without any acceleration or movement of the objects themselves. The space between objects shrinks or grows as the various geodesics converge or diverge.


title: Expansion of the universe

text: Because this expansion is caused by relative changes in the distance-defining metric, this expansion (and the resultant movement apart of objects) is not restricted by the speed of light upper bound of special relativity. Two reference frames that are globally separated can be moving apart faster than light without violating special relativity, although whenever two reference frames diverge from each other faster than the speed of light, there will be observable effects associated with such situations including the existence of various cosmological horizons.


title: Expansion of the universe

text: Theory and observations suggest that very early in the history of the universe, there was an inflationary phase where the metric changed very rapidly, and that the remaining time-dependence of this metric is what we observe as the so-called Hubble expansion, the moving apart of all gravitationally unbound objects in the universe. The expanding universe is therefore a fundamental feature of the universe we inhabit – a universe fundamentally different from the static universe Albert Einstein first considered when he developed his gravitational theory.


title: Expansion of the universe

text: In expanding space, proper distances are dynamical quantities that change with time. An easy way to correct for this is to use comoving coordinates, which remove this feature and allow for a characterization of different locations in the universe without having to characterize the physics associated with metric expansion. In comoving coordinates, the distances between all objects are fixed and the instantaneous dynamics of matter and light are determined by the normal physics of gravity and electromagnetic radiation. Any time-evolution however must be accounted for by taking into account the Hubble law expansion in the appropriate equations in addition to any other effects that may be operating (gravity, dark energy, or curvature, for example). Cosmological simulations that run through significant fractions of the universe's history therefore must include such effects in order to make applicable predictions for observational cosmology.


title: Expansion of the universe

text: In principle, the expansion of the universe could be measured by taking a standard ruler and measuring the distance between two cosmologically distant points, waiting a certain time, and then measuring the distance again, but in practice, standard rulers are not easy to find on cosmological scales and the timescales over which a measurable expansion would be visible are too great to be observable even by multiple generations of humans. The expansion of space is measured indirectly. The theory of relativity predicts phenomena associated with the expansion, notably the redshift-versus-distance relationship known as Hubble's Law; functional forms for cosmological distance measurements that differ from what would be expected if space were not expanding; and an observable change in the matter and energy density of the universe seen at different lookback times.


title: Expansion of the universe

text: The first measurement of the expansion of space came with Hubble's realization of the velocity vs. redshift relation. Most recently, by comparing the apparent brightness of distant standard candles to the redshift of their host galaxies, the expansion rate of the universe has been measured to be H = . This means that for every million parsecs of distance from the observer, the light received from that distance is cosmologically redshifted by about . On the other hand, by assuming a cosmological model, e.g. Lambda-CDM model, one can infer the Hubble constant from the size of the largest fluctuations seen in the Cosmic Microwave Background. A higher Hubble constant would imply a smaller characteristic size of CMB fluctuations, and vice versa. The Planck collaboration measure the expansion rate this way and determine H = . There is a disagreement between the two measurements, the distance ladder being model-independent and the CMB measurement depending on the fitted model, which hints at new physics beyond our standard cosmological models.


title: Expansion of the universe

text: The Hubble parameter is not thought to be constant through time. There are dynamical forces acting on the particles in the universe that affect the expansion rate. It was earlier expected that the Hubble parameter would be decreasing as time went on due to the influence of gravitational interactions in the universe, and thus there is an additional observable quantity in the universe called the deceleration parameter, which cosmologists expected to be directly related to the matter density of the universe. Surprisingly, the deceleration parameter was measured by two different groups to be less than zero (actually, consistent with −1), which implied that today the Hubble parameter is converging to a constant value as time goes on. Some cosmologists have whimsically called the effect associated with the "accelerating universe" the "cosmic jerk". The 2011 Nobel Prize in Physics was given for the discovery of this phenomenon.


title: Expansion of the universe

text: In October 2018, scientists presented a new third way (two earlier methods, one based on redshifts and another on the cosmic distance ladder, gave results that do not agree), using information from gravitational wave events (especially those involving the merger of neutron stars, like GW170817), of determining the Hubble Constant, essential in establishing the rate of expansion of the universe.


title: Expansion of the universe

text: At cosmological scales, the present universe conforms to Euclidean space, what cosmologists describe as "geometrically flat", to within experimental error.


title: Expansion of the universe

text: Consequently, the rules of Euclidean geometry associated with Euclid's fifth postulate hold in the present universe in 3D space. It is, however, possible that the geometry of past 3D space could have been highly curved. The curvature of space is often modeled using a non-zero Riemann curvature tensor in Curvature of Riemannian manifolds. Euclidean "geometrically flat" space has a Riemann curvature tensor of zero.


title: Expansion of the universe

text: "Geometrically flat" space has 3 dimensions and is consistent with Euclidean space. However, spacetime on the other hand, is 4 dimensions; it is not flat according to Einsten's general theory of relativity. Einstein's theory postulates that "matter and energy curve spacetime, and there are enough matter and energy lying around to provide for curvature."


title: Expansion of the universe

text: In part to accommodate such different geometries, the expansion of the universe is inherently general relativistic. It cannot be modeled with special relativity alone: though such models exist, they are at fundamental odds with the observed interaction between matter and spacetime seen in our universe.


title: Expansion of the universe

text: The images to the right show two views of spacetime diagrams that show the large-scale geometry of the universe according to the ΛCDM cosmological model. Two of the dimensions of space are omitted, leaving one dimension of space (the dimension that grows as the cone gets larger) and one of time (the dimension that proceeds "up" the cone's surface). The narrow circular end of the diagram corresponds to a cosmological time of 700 million years after the Big Bang, while the wide end is a cosmological time of 18 billion years, where one can see the beginning of the accelerating expansion as a splaying outward of the spacetime, a feature that eventually dominates in this model. The purple grid lines mark off cosmological time at intervals of one billion years from the Big Bang. The cyan grid lines mark off comoving distance at intervals of one billion light years in the present era (less in the past and more in the future). Note that the circular curling of the surface is an artifact of the embedding with no physical significance and is done purely for illustrative purposes; a flat universe does not curl back onto itself. (A similar effect can be seen in the tubular shape of the pseudosphere.)


title: Expansion of the universe

text: The brown line on the diagram is the worldline of Earth (or more precisely its location in space, even before it was formed). The yellow line is the worldline of the most distant known quasar. The red line is the path of a light beam emitted by the quasar about 13 billion years ago and reaching Earth at the present day. The orange line shows the present-day distance between the quasar and Earth, about 28 billion light years, which is a larger distance than the age of the universe multiplied by the speed of light, "ct".