title: X-Force

text: The new X-force consists of Cable, Marrow (who despite losing her powers during M-Day is repowered using a psychic headband), Psylocke, Fantomex, and Dr. Nemesis. They are investigating an explosion in Alexandria that put Hope Summers into a coma and find a new mutant nicknamed Meme, since she can only communicate through computers, as her body is comatose. They discover Russian billionaire Yevgeny-Malevitch Volga is behind Alexandria explosion and the kidnapping. He has been kidnapping mutants and supercharging them with kinetic energy and making them into human bombs. While in Paris, they pretend to kill a mutant that can read the minds of cats, so the French secret mutant forces, Le Bureaus Discret, will come to investigate, then they kidnap Le Necrogateur, a mutant that can read the minds of the deceased. Using his powers they find Volga's headquarters and that Volga found a mutant that can teleport between dimensions. Threatening the death of his family, they force the teleporting mutant to bring back a powerful weapon from Earth 1287, that creates super soldiers but greatly decreases their lifespan. During the attack on Volga's base Marrow discovers that she was pregnant during M-Day and volunteered to get her powers back, but at the cost of her pregnancy. She has a mental breakdown and X-Force is captured. It seems all is lost when Cable is super-charged and blown up by Volga. It turns out that Cable was present at Alexandria and it was him and Hope that caused the explosion when he was supercharged by Volga's henchman. Hope mimicked his powers and the chemicals caused her to fall into a coma. Cable survived the explosions since he wasn't really there—Dr. Nemesis keeps Cable locked in stasis and creates a clone of him everyday and uploads his memories. The Cable and Dr. Nemesis attack Volga's base again and teleports his supercharged henchmen into outer space and then Volga seems to commit suicide by super-charging himself and killing the Cable clone again, but Marrow creates a bone shield to protect the team. Volga's spirit survives the explosion and another Cable clone emerges from the X-Force base to mourn over Hope, who was able to manifest herself in a digital avatar by copying the powers of a brain-dead mutant, Meme. Psylocke is able to discover the switch with her psychic powers, but promises Hope that she won't tell Cable.


title: X-Force

text: Cable and the X-Force who have barely survived their ordeal with Volga, track a team of British special forces into the desert. The team is tracking terrorists known as the Quaddees. It turns out Volga sold his tech to both the British and the Quaddees. X-Force begins abducting the team, but are attacked by Pete Wisdom, Meggan, and Excalibur from MI-13. Soon the Quaddees kidnap one member of the team, so the three groups decide to work together. Psylocke is able to find out that the super-powered British Special forces team will all die soon from Volga's tech, so the team sacrifices themselves so MI-13 and X-Force can escape. They also learn that there's a secret organization called the Yellow Eye spying on all mutants, who also kidnapped Domino. This series also retcons multiple X-Men backstories with the introduction of ForgetMeNot. His power is to immediately be forgotten by anybody who speaks with him and to be completely unnoticed by people around him unless he acknowledges them. Only Xavier knows of his existence—even setting a psychic alarm clock to check in with ForgetMeNot every hour to remind him somebody remembers him. He hangs around the X-Mansion repelling attackers and saving the X-Men multiple times, without them realizing it and blaming it on dumb luck or deus ex machina. Dr. Nemesis, using an algorithm based on blurs in camera footage and missing toilet paper at the X-Mansion creates a teleporter to bring ForgetMeNot to the X-Force base on an abandoned S.H.I.E.L.D. Helicarrier. The team has great difficulty catching ForgetMeNot, since whenever he hides they forgot about him then take a coffee break, where a prerecorded video by Dr. Nemesis plays reminding them to find ForgetMeNot. This turns into a vicious cycle, almost like a time loop, until ForgetMeNot realizes that he was brought here to trick the Yellow Eye spybots (which look like tiny gnats) into allowing himself to be tracked, place a reverse tracking beacon on one and then the drone will forget him immediately and not self-destruct. This plan works; however, Fantomex then kills ForgetMeNot. Stating that he knew about him all the time since he has three brains and nanobots in his brain. Fantomex says he does it because he is evil and bored. The ships cleaning bots sweep away ForgetMeNot's body and Dr. Nemesis forgets speaking with him and assumes he figured out how to track the spybots on his own.


title: X-Force

text: The team attacks the Yellow Eye base, but during the battle Meme/Hope Summers hacks into Fantomex's consciousness, thanks to his nanobot brain, in order to learn why he broke up with her. He then reveals that he knew Hope Summers was posing as Meme. He then betrays the team and plans to use the Yellow Eye tracking technology to find his missing clones (Cluster and Weapon XIII). Luckily, it turns out Domino was brainwashed by the Yellow Eye, but Meme was able to hack into her and free her. She then shoots Fantomex in the head. It turns out Yellow Eye is actually Mojo, who reveals that Meme is actually Hope Summers to the rest of the team. Cable debates using the Yellow Eye Technology, but Psylocke wants the facility destroyed. They don't have time to debate since the second clone of Cable was already at the facility with Dr. Nemesis tracking Volga during the prior fight. The team doesn't have time to debate the morality since Fantomex was able to recode Volga's super virus code when he died and E.V.A. reloaded the virus to give her unlimited superpowers. However, since his mind is still mechanical Meme hacked into him making him think he killed the team, while they actually escaped. Back at the base Cable tricks Fantomex into fighting him, but is actually getting Fantomex to destroy various spy agencies and evil organizations. ForgetMeNot also reveals himself to Hope Summers and explains that the original Meme is still alive and saved him by transferring his consciousness and then repaired his body with the ships clean up bots. He reveals that Meme is actually dying, and once she dies Hope will not be able to copy Meme's powers and communicate with the team using her hacking powers. After Meme dies, ForgetMeNot reveals himself to the team and asks Marrow to touch Hope's body, then Hopes copies Marrow's healing factor and is able to temporarily heal herself enough to play a video showing how Cable has been manipulating the team. ForgetMeNot then pushes Psylocke into Hope, who then copies her psychic powers and reveals to the team her troubles childhood and how despite Cable saving her life by traveling between dimensions, she has outgrown him morally and doesn't look up to him. Marrow then kills the Cable clone. Hope also revealed their location to Fantomex, who is on his way to kill them. The team doesn't think they have a chance at stopping him, but Hope has a plan that will only work if they act as a team. Domino and Psylocke distract Fantomex while ForgetMeNot sneaks up to him and teleports him to Hope, who copies his super-powers, as well as the entire teams. She releases all the Cable clones against Fantomex. Hope, using Dr. Nemesis's super intellect, then figures out that Fantomex doesn't believe he is imperfect, but reveals to him that perfect requires cracks and inadequacies and perfection is really being a team. Fantomex cannot comprehend this and has a mental breakdown. Psylocke then uses her psi-blade to scramble his mind. The team later reveals they "fired" Cable from the team.


title: X-Force

text: Issues #57–58 of the first series were part of the Onslaught storyline which was a top vote-getter for the Comics Buyer's Guide Fan Award for Favorite Comic-Book Story for 1997.


title: X-Force

text: Before the team best known as X-Force debuted, Marvel introduced an unrelated, little-known group also called X-Force. It was a short-lived group that was designed to replace Freedom Force. The members were not mutants, but received their powers artificially and were named after the X-Men. This group was organized by a government agency known as M Branch and only appeared in the pages of "Cloak and Dagger" #9–10 (1990).


title: X-Force

text: In the alternate reality of the "Days of Future Now" storyline, the X-Force consists of Banshee, Black Tom Cassidy, Cannonball, Domino, Meltdown and Omega Red.


title: X-Force

text: X-Force appears in Deadpool's ending in "Ultimate Marvel vs. Capcom 3", consisting of Domino, Fantomex, and Archangel.


title: Karl-Heinz Rummenigge

text: Karl-Heinz "Kalle" Rummenigge (; born 25 September 1955) is a German football executive and former professional player. He was the longtime Chairman of Executive Board of FC Bayern München AG, a daughter company of German Bundesliga team Bayern Munich.


title: Karl-Heinz Rummenigge

text: As a player, Rummenigge had his greatest career success with Bayern Munich, where he won the Intercontinental Cup, two European Cups, as well as two league titles and two domestic cups. He was also honoured twice as European Footballer of the Year.


title: Karl-Heinz Rummenigge

text: A member of the West Germany national team, Rummenigge won the 1980 European Championship and was part of the squad that finished runner-up in the 1982 FIFA World Cup and at the 1986 World Cup.


title: Karl-Heinz Rummenigge

text: Rummenigge is a former chairman of the European Club Association, serving in that capacity from 2008 until 2017.


title: Karl-Heinz Rummenigge

text: He joined Bayern Munich in 1974, coming from the Westphalian amateur side Borussia Lippstadt, for a transfer fee of ca. €10,000. He immediately showed great strength as a dribbler. His scoring qualities were initially insignificant, but would find great improvement in later years, particularly after the arrival of coach Pal Csernai in 1979. In 1979–80, he scored 26 goals and became for the first time the Bundesliga's top striker, a feat he repeated in 1981 and 1984 with 29 and 26 goals, respectively.


title: Karl-Heinz Rummenigge

text: With Bayern he won the European Cup in 1975 and 1976. In 1975, he did not take part in the final of the competition, whilst in the year thereafter a glass of brandy sufficiently prepared the nervous Rummenigge to contribute to the defeat of AS Saint-Étienne. In the same year he became also part of the team that prevailed in the Intercontinental Cup finals against Cruzeiro EC from Belo Horizonte.


title: Karl-Heinz Rummenigge

text: In the era of coach Csernai he found in midfielder Paul Breitner a congenial partner and he formed such a formidable one-two-punch that they were only called Breitnigge (name invented by German newspaper Bild).


title: Karl-Heinz Rummenigge

text: The club, then often dubbed as "FC Breitnigge", won in this period the Bundesliga title in 1980 and 1981, and the DFB-Pokal in 1982 and 1984. A renewed triumph in the European Cup was denied, when the club lost the 1982 final narrowly against Aston Villa. In the season before Rummenigge was top-scorer in this competition with 6 goals.


title: Karl-Heinz Rummenigge

text: His substantial contribution to the successes of the club and the German national football team found also expression in personal honours. In 1980, he was named German Footballer of the Year and in '80–81 the European Footballer of the Year.


title: Karl-Heinz Rummenigge

text: In 1984, aged 29, he was sold for a record fee of €5.7m to Inter Milan. Despite a notable beginning, in which he helped the team to compete until the end for the 1984–85 "Scudetto", Rumenigge's career in Italy was mostly marred by injury problems. At the end of his contract in 1987, Rummenigge moved on to Swiss first division club Servette FC in Geneva, where he saw his career out. In his last season, 1988–89, he had his last success, becoming top scorer in the Swiss league with 24 goals.


title: Karl-Heinz Rummenigge

text: With the West German national team he took part in the 1978 World Cup in Argentina, 1982 World Cup in Spain and the 1986 World Cup in Mexico. In 1978, West Germany exited in the second group stage of the tournament. In 1982 and 1986, the team was runner-up behind Italy and Argentina.


title: Karl-Heinz Rummenigge

text: Rummenigge also took part in two European Championship tournaments. In the 1980 competition in Italy, West Germany defeated Belgium in the final by 2–1 and won the trophy.


title: Karl-Heinz Rummenigge

text: Altogether, between 1976 and 1986, Rummenigge amassed 95 caps and scored 45 goals for West Germany, including one in extra-time in the 1982 World Cup semi-final victory over France, and one in the losing 1986 World Cup final match against Argentina. He also scored a hat-trick in a group stage game against Chile during the 1982 World Cup.


title: Karl-Heinz Rummenigge

text: One of the most talented attacking players of his generation, Rummenigge was often lauded as a highly versatile forward, capable of playing as a second striker, winger, or flat-out centre forward. His main strengths were his pace, dribbling, heading and goalscoring ability, from both close range and from outside the box. He also had a penchant for scoring from awkward situations.


title: Karl-Heinz Rummenigge

text: Rummenigge was also praised for his both-footedness, leadership and physical strength. However, his later career was greatly affected by injuries, in particular after his move to Inter Milan.


title: Karl-Heinz Rummenigge

text: In autumn 1991, Bayern Munich invited Franz Beckenbauer and Rummenigge to return to the club as vice presidents. Rummenigge held this position until February 2002, when he was appointed Chairman of Executive Board of the newly corporatised football department of the club (FC Bayern München AG). According to the club, "in his role as chairman he is responsible for external relations, new media, board affairs and representing the holding company on national and international bodies."


title: Karl-Heinz Rummenigge

text: During his tenure, Bayern Munich managed to move to their new stadium, Allianz Arena. On 1 June 2021, it was announced that Oliver Kahn will take over his CEO position at Bayern Munich starting 1 July 2021.


title: Karl-Heinz Rummenigge

text: In April 1983, the British pop duo Alan & Denise recorded a tribute song about his "sexy knees" in the song "Rummenigge". The single reached number 43 in German charts.


title: Karl-Heinz Rummenigge

text: From 1990 until 1994, Rummenigge worked as a TV co–commentator for matches of the German national team.


title: Karl-Heinz Rummenigge

text: His brother Michael Rummenigge was also a noteworthy footballer. He played as forward for Bayern Munich and Borussia Dortmund from 1982 to 1988 and 1988 to 1994, respectively. He also represented Germany on two occasions between 1983 and 1986.


title: Felicia Pearson

text: Felicia Pearson (born May 18, 1980) is an American actress, rapper and author. She played Felicia "Snoop" Pearson on "The Wire" and wrote a 2007 memoir, "Grace After Midnight," detailing her troubled childhood and time in prison for second-degree murder.


title: Felicia Pearson

text: Pearson was born in Baltimore, Maryland, the daughter of two incarcerated drug addicts, and was raised in an East Baltimore foster home. Born premature and weighing three pounds, she was not expected to live. She was so small that she was fed with an eyedropper until she could be fed normally. According to her memoir, "Grace After Midnight", she met her biological parents very few times, her mother was a crack addict, and her father was an armed robber. As a result of this, she decided to go by her foster family's surname.


title: Felicia Pearson

text: Pearson was a tomboy from a young age and worked as a drug dealer as a teenager. At the age of fourteen, she was convicted of second degree murder after the shooting of a girl named Okia Toomer and was sentenced to two eight-year terms, to be served consecutively, at the Maryland Correctional Institution for Women in Jessup, Maryland. She was released after six and a half years.


title: Felicia Pearson

text: Pearson said her life turned around at the age of eighteen, when Arnold Loney, a local drug dealer who looked out for her and sent her money in prison, was shot and killed. He had coined her nickname "Snoop," because she reminded him of Charlie Brown's beagle Snoopy in the comic strip "Peanuts". While in prison, Pearson earned her GED. She was released in 2000, and landed a local job fabricating car bumpers, but was fired after two weeks when her employer learned she had a prison record.


title: Felicia Pearson

text: Pearson met Michael K. Williams, who played Omar Little on "The Wire," in a Baltimore club. He invited her to come to the set one day, and introduced her to the writers and the producers. After subsequent auditions, she was offered a role in the series. For her performance in "The Wire," Stephen King called her "perhaps the most terrifying female villain to ever appear in a television series."


title: Felicia Pearson

text: Her appearance on the show kickstarted her acting career, leading to appearances in music videos for R&B singer Lil' Mo's "Dem Boyz"; rapper Rick Ross' "The Boss" and "Here I Am"; rapper Ace Hood's "Cash Flow"; A$AP Ferg's "Shabba (feat ASAP Rocky)" and Snoop Dogg's "So Many Pros." She has appeared in the Spike Lee films "Da Sweet Blood of Jesus," and "Chi-Raq," and in the CBS police procedural drama "Blue Bloods," titled "Good Cop Bad Cop."


title: Felicia Pearson

text: Pearson is featured in the song "It's a Stick Up" with Tony Yayo and Mazaradi Fox, with its music video featuring clips from "The Wire".


title: Felicia Pearson

text: Pearson has volunteered as a prison visitor, worked on anti-violence and literacy campaigns for youth, and supported "The Stay Strong Foundation".


title: Felicia Pearson

text: On March 10, 2011, Pearson and sixty others were arrested and charged with drug offenses. The arrest was made during a predawn raid at her home in Baltimore, following a five-month DEA operation. At the first hearing after Pearson's arrest, Judge John Addison Howard denied her bail due to Pearson's acting ability, stating: "Well, you can change your appearance, I've seen the episodes of "The Wire" in which you appear. You look very different than you do here today, and I'm not talking about the jumpsuit, I'm talking about your general appearance." After a month in jail, Pearson was offered bail of $50,000 on April 8, 2011. In August 2011, she pleaded guilty to the charges the day before her trial was to begin. She was sentenced to a suspended seven-year prison term, with credit for time served, and given three years of supervised probation. She pled guilty because the trial could have been a year or more and Pearson wanted to move on with her life according to FOX news affiliates in Maryland.


title: Juan Sebastián Verón

text: Juan Sebastián Verón (; born 9 March 1975) is an Argentine former professional footballer and current chairman of Estudiantes de La Plata, where he had served as Director of Sports. A former midfielder, Verón's career started in Estudiantes, continued in Argentina's Boca Juniors, and included stints in several clubs in the Italian Serie A (where he won the "Scudetto" with Lazio and with Internazionale, and a UEFA Cup with Parma), and England's Manchester United and Chelsea. In 2006, Verón returned to Estudiantes, where he remained until his retirement in 2014, aside from a brief spell with Brandsen. He announced his short return to first team football would occur in the 2017 Copa Libertadores.


title: Juan Sebastián Verón

text: At international level, Verón obtained 72 caps for Argentina between 1996 and 2010, scoring nine goals. He represented his nation at three FIFA World Cups, and at the 2007 Copa América, where he won a runners-up medal.


title: Juan Sebastián Verón

text: In 2004, he was included in the FIFA 100 list of the 125 greatest living footballers, selected by Pelé as part of FIFA's centenary celebrations. Verón has both Argentine and Italian citizenship. His nickname is "La Brujita" ("The Little Witch"), a nod to his father Juan Ramón who was known as "La Bruja" ("The Witch") and was also a championship winning player with Estudiantes.


title: Juan Sebastián Verón

text: In 1993, Verón signed for Estudiantes de La Plata and in 1995 helped the team to return to the Argentine Primera División. In 1996, he joined Boca Juniors, playing 17 games and scoring three goals, alongside Diego Maradona. He made his international debut for Argentina against Poland in the same year. Sven-Göran Eriksson signed him for Sampdoria shortly afterwards.


title: Juan Sebastián Verón

text: In 1998, after playing for Argentina at the 1998 World Cup, he signed for Parma for £15 million. The following year, Parma won the Coppa Italia and the UEFA Cup. Eriksson then signed him again, this time for Lazio in an £18.1 million deal, with Verón reportedly netting a weekly wage of £48,000. He made his debut for Lazio in the Italian side's 1–0 victory over Manchester United in the European Super Cup in Monaco.


title: Juan Sebastián Verón

text: In 2000, Verón was the driving force for Lazio as they captured the "Scudetto", the Coppa Italia and the Italian Super Cup, as he scored 8 goals.


title: Juan Sebastián Verón

text: But in February 2000, he was under investigation by Italian police for a possible fake Italian passport in order to avoid the non-EU quota. However, the charge was cleared by FIGC in June 2001, because his passport really had been issued by Italian officials and he avoided a ban. However, a new controversy was exposed that Verón and his agent may have used fake documents submitted to the Italian government in order to allege to the government that Verón had Italian descent and granted him an Italian passport, which claimed an Italian, Giuseppe Antonio Porcella was Verón's great-grandfather Ireneo Portela. Manchester United even inserted a clause in the transfer document for a possible ban. In July 2002, he was called to appear before Italy's state prosecutor to answer allegations he illegally acquired an Italian passport. Elena Tedaldi, the agent who helped Verón to get the passport, was jailed for 15 months, but Verón himself and former Lazio chairman Sergio Cragnotti were acquitted in 2007. It is because Verón also had Italian descent through another great-grandparent and it was Tedaldi who used the fake documents.


title: Juan Sebastián Verón

text: After the 2000–01 season, he moved from Lazio to Manchester United on 12 July for a fee of £28.1 million on a five-year deal, the most expensive transfer in English football at that time, also becoming the first non-UEFA player to break the English transfer record. On signing for Manchester United, he was quoted as saying that he had no fear of the Premier League.


title: Juan Sebastián Verón

text: Verón's first season at Old Trafford started well. In September 2001 he found the back of the net in three of Manchester United's four outings, including a goal and an assist in a 5–3 comeback win at Tottenham Hotspur, which ultimately led to him being awarded the Premier League Player of the Month. But as the season progressed and fatigue settled in, his performances declined. He would have trouble adapting to the relentlessly faster pace of the Premier League, where he was not allowed the same space and time on the ball.


title: Juan Sebastián Verón

text: There was plenty of pressure on him at the start of his second season at Old Trafford and his performances did improve considerably, especially in the Champions League, where he excelled due to the slower tempo of the matches, scoring four goals, and was at the heart of United's successes in the group stages. However, injury meant that he missed much of the end of the season. Questions over his performance led to an expletive-laden tirade against the media by manager Sir Alex Ferguson in support of Verón: "[Verón] is a fucking great player" were his parting words. "And you're all fucking idiots." However, fans and pundits alike agreed that the signing was an expensive flop. Verón later commented that the reason for his fitness problems and struggles with injuries at Manchester United were due to the less intense summer pre-season training in England.


title: Juan Sebastián Verón

text: When Chelsea paid £15 million for him two years on, following the arrival of Roman Abramovich, Verón claimed that he wanted to stay and fight for his place at Old Trafford, but Ferguson was willing to let Chelsea talk to him and he was eventually convinced by then Chelsea manager Claudio Ranieri to make the move to Stamford Bridge. His transfer fee to Chelsea was about half that of his record-breaking transfer of just two years before.


title: Juan Sebastián Verón

text: Verón made an excellent start to his Chelsea career by scoring the opening goal in a 2–1 victory over Liverpool at Anfield, but he fell away with injury problems as the 2003–04 season progressed and made only 15 appearances for Chelsea.


title: Juan Sebastián Verón

text: "The Times" listed Verón's transfers to Manchester United and Chelsea among the 50 worst transfers ever in Premier League history. His several big-money transfers made Verón, at the time, the most expensive footballer in history, with a cumulative total of £77 million.


title: Juan Sebastián Verón

text: When José Mourinho took over as Chelsea manager the following season, Verón was loaned out to Internazionale initially for 2004–05, but he subsequently returned to Inter on loan for a further season. With Inter, he was part of the squad that won the 2005 Coppa Italia, 2006 Coppa Italia, and also by default the 2006 Serie A title after Juventus were stripped of the title for a match fixing scandal.


title: Juan Sebastián Verón

text: In mid-2006, Verón made it known that he wished to return to his native Argentina for the 2006–07 season. He received offers from Boca Juniors and River Plate, but chose his boyhood club Estudiantes de La Plata, of whom he is a declared fan and has made significant donations in the past to upgrade the club training facilities. Chelsea agreed to loan Verón to Estudiantes for a season, until the end of his contract with the English club. On 13 December 2006, he helped Estudiantes win the Apertura 2006 tournament, its first in 23 years, in a final play-off match final over Boca Juniors. Some rival fans booed him, arguably dating back to his sub-par performances during the 2002 FIFA World Cup, but Verón was ranked among the top three players in the 2006 Argentine League by sports newspaper "Olé".


title: Juan Sebastián Verón

text: Following his donations to the club's training grounds, Verón was a decisive factor in the agreement with La Plata city hall to update Estudiantes' historic stadium to modern standards. Verón personally engaged then Argentine president Néstor Kirchner to kick-start the negotiations, which had been stalled by La Plata mayor Julio Alak. Verón indicated that he may run for Estudiantes president in the future.


title: Juan Sebastián Verón

text: In July 2007, Kevin Payne, president of Major League Soccer club D.C. United, met with Verón in Buenos Aires to discuss a possible transfer, but Verón decided to stay in Estudiantes. Verón suffered from a string of minor injuries after his return from the 2007 Copa América, and missed a number of important games during the 2007–08 season. In early 2008, several football personalities chose Verón as the best player in the Argentine league.


title: Juan Sebastián Verón

text: Veron's fitness improved in time for the 2008–09 season, in which Estudiantes reached the finals of the Copa Sudamericana and secured a place in the 2009 Copa Libertadores.


title: Juan Sebastián Verón

text: In 2009, he played in the Copa Libertadores for the second time, having seen Estudiantes eliminated in the round of 16 in the previous year by eventual champions Liga de Quito. After displaying his usual excellent level of play throughout the tournament, he found himself leading Estudiantes into the final for the first time since 1971. The Copa Libertadores has long been a special competition for Estudiantes and its fans, ever since the team won three consecutive titles from 1968 to 1970 with Verón's father playing a key role on the left wing. Verón certainly shared this affinity for the most prestigious title in the American continent, as evidenced by his declaration before the final: "I would trade everything I've won for this title." His dream came true as Estudiantes won the final, after an aggregate of 2–1. A 0–0 tie in La Plata and a dramatic 2–1 win away in Belo Horizonte against Brazil's Cruzeiro sealed "el pincha's" triumph. Verón was chosen by visitors to "fifa.com" as the best player of the 2009 Copa Libertadores.


title: Juan Sebastián Verón

text: Verón was twice elected South American Footballer of the Year (2008 and 2009) by Uruguayan newspaper "El País", a title that is cited worldwide.


title: Juan Sebastián Verón

text: In December 2016, Verón returned to professional football, signing an 18-month contract to play for Estudiantes in the 2017 Copa Libertadores. Verón had vowed to return if fans bought 65% of the boxes at the club's new stadium, and fulfilled that promise by signing an 18-month contract; he would be given a minimum salary that would go directly back to the club for everyday operations. He made his first appearance for the club since coming out of retirement in a 1–0 friendly victory over Bahia in the Florida Cup, in Orlando, on 15 January 2017, playing the first half, before being substituted.


title: Juan Sebastián Verón

text: Verón was called up for the 1998 FIFA World Cup in France, where Argentina was eliminated by the Netherlands in the quarter-finals following a 2–1 defeat; during the match, Veron set-up Claudio López's goal. A rumour (never confirmed) that Verón had failed an internal doping test, and allegations of laziness hampered his relationship with the media and fans. He was called up again for the 2002 World Cup in South Korea/Japan, where Verón was regarded as a key player and captained the side in place of the injured Roberto Ayala. Some fans held him personally responsible for Argentina's dismal performance, which included a loss to England and elimination in the group phase.


title: Juan Sebastián Verón

text: After then-national coach José Pekerman omitted him from the 2006 World Cup squad, his replacement, Alfio Basile recalled Verón to the national squad in February 2007, based on his performance in Estudiantes's 2006 championship team. Verón was a starter in the Argentine team that reached the final of 2007 Copa América. Due to injuries and Estudiantes's busy schedule, Verón did not feature in the immediate plans of national coach Diego Maradona, but was recalled to the Argentine squad as a second-half substitute in the 4–0 win over Venezuela on 28 March 2009, Maradona's first competitive game in charge of the national team. He also played in the starting XI in a 2010 FIFA World Cup qualifier against Colombia on 6 June 2009 and was selected by manager Diego Maradona in the final 23-man squad for the finals of the 2010 FIFA World Cup.


title: Juan Sebastián Verón

text: Verón started Argentina's first group match against Nigeria, and provided the assist for Gabriel Heinze's goal. After missing the match against South Korea due to injury, Verón returned to the starting line-up against Greece and played the full 90 minutes as Argentina won 2–0. He came on as a substitute for Carlos Tévez in the 69th minute in Argentina's 3–1 victory over Mexico in the Round of 16, but did not feature during the quarterfinal loss to Germany.


title: Juan Sebastián Verón

text: On 26 August 2010, Verón retired from international football. Nevertheless, Verón appeared again for Argentina in the 2011 Superclásico de las Américas, a two legged, non-FIFA sanctioned exhibition, between Argentina and Brazil's domestically-based players.


title: Juan Sebastián Verón

text: In December 2012, Verón returned to Estudiantes to work as Director of Sports of the institution. In a press conference, club president Enrique Lombardi stated that Verón would not receive any remuneration for his work at the club.


title: Juan Sebastián Verón

text: Verón is the eldest son of former Argentina striker Juan Ramón Verón, who scored against Manchester United for Estudiantes at Old Trafford in the 1968 Intercontinental Cup. He was born the day his father played a derby for Estudiantes against cross-town rivals Gimnasia y Esgrima. As a boy, Verón dreamed of playing for English club Sheffield United, as his uncle, Pedro Verde, played for the club at the time. When his son started to play professionally, his father tried to persuade one of his former clubs Panathinaikos to sign him. However, after a short trial with them, they finally decided that he was not good enough for their team. After his transfer to Manchester United, Verón said, "So there I was hoping to play for Sheffield United and here I am at Manchester United!"


title: Juan Sebastián Verón

text: Verón was a talented, complete, influential and versatile midfielder, who usually functioned as a playmaker; he was capable of playing both as an attacking midfielder and in the centre, or even just in front of the defensive line, as a deep-lying playmaker, due to his awareness, ability to read the game, tackle and dictate the tempo of his team's play or orchestrate his team's attacking moves from deeper positions with his passing after winning back the ball, in addition to providing assists and creating goalscoring opportunities for teammates. He could also get forward and score goals and often functioned in a free role in midfield. A strong, athletic, tenacious, hard-working and physical player, in his prime, he was gifted with pace, good footwork and excellent technical ability, as well as outstanding vision, creativity, passing range and possessing a powerful shot from distance with either foot. He was also an accurate set-piece taker, known for his powerful, bending free kicks with his right foot.


title: Fundamental interaction

text: In physics, the fundamental interactions, also known as fundamental forces, are the interactions that do not appear to be reducible to more basic interactions. There are four fundamental interactions known to exist: the gravitational and electromagnetic interactions, which produce significant long-range forces whose effects can be seen directly in everyday life, and the strong and weak interactions, which produce forces at minuscule, subatomic distances and govern nuclear interactions. Some scientists hypothesize that a fifth force might exist, but these hypotheses remain speculative.


title: Fundamental interaction

text: Each of the known fundamental interactions can be described mathematically as a "field". The gravitational force is attributed to the curvature of spacetime, described by Einstein's general theory of relativity. The other three are discrete quantum fields, and their interactions are mediated by elementary particles described by the Standard Model of particle physics.


title: Fundamental interaction

text: Within the Standard Model, the strong interaction is carried by a particle called the gluon and is responsible for quarks binding together to form hadrons, such as protons and neutrons. As a residual effect, it creates the nuclear force that binds the latter particles to form atomic nuclei. The weak interaction is carried by particles called W and Z bosons, and also acts on the nucleus of atoms, mediating radioactive decay. The electromagnetic force, carried by the photon, creates electric and magnetic fields, which are responsible for the attraction between orbital electrons and atomic nuclei which holds atoms together, as well as chemical bonding and electromagnetic waves, including visible light, and forms the basis for electrical technology. Although the electromagnetic force is far stronger than gravity, it tends to cancel itself out within large objects, so over large (astronomical) distances gravity tends to be the dominant force, and is responsible for holding together the large scale structures in the universe, such as planets, stars, and galaxies.


title: Fundamental interaction

text: Many theoretical physicists believe these fundamental forces to be related and to become unified into a single force at very high energies on a minuscule scale, the Planck scale, but particle accelerators cannot produce the enormous energies required to experimentally probe this. Devising a common theoretical framework that would explain the relation between the forces in a single theory is perhaps the greatest goal of today's theoretical physicists. The weak and electromagnetic forces have already been unified with the electroweak theory of Sheldon Glashow, Abdus Salam, and Steven Weinberg, for which they received the 1979 Nobel Prize in physics. Some physicists seek to unite the electroweak and strong fields within what is called a Grand Unified Theory (GUT). An even bigger challenge is to find a way to quantize the gravitational field, resulting in a theory of quantum gravity (QG) which would unite gravity in a common theoretical framework with the other three forces. Some theories, notably string theory, seek both QG and GUT within one framework, unifying all four fundamental interactions along with mass generation within a theory of everything (ToE).


title: Fundamental interaction

text: In his 1687 theory, Isaac Newton postulated space as an infinite and unalterable physical structure existing before, within, and around all objects while their states and relations unfold at a constant pace everywhere, thus absolute space and time. Inferring that all objects bearing mass approach at a constant rate, but collide by impact proportional to their masses, Newton inferred that matter exhibits an attractive force. His law of universal gravitation implied there to be instant interaction among all objects. As conventionally interpreted, Newton's theory of motion modelled a "central force" without a communicating medium. Thus Newton's theory violated the tradition, going back to Descartes, that there should be no action at a distance. Conversely, during the 1820s, when explaining magnetism, Michael Faraday inferred a "field" filling space and transmitting that force. Faraday conjectured that ultimately, all forces unified into one.


title: Fundamental interaction

text: In 1873, James Clerk Maxwell unified electricity and magnetism as effects of an electromagnetic field whose third consequence was light, travelling at constant speed in a vacuum. If his electromagnetic field theory held true in all inertial frames of reference, this would contradict Newton's theory of motion, which relied on Galilean relativity. If, instead, his field theory only applied to reference frames at rest relative to a mechanical luminiferous aether—presumed to fill all space whether within matter or in a vacuum and to manifest the electromagnetic field—then it could be reconciled with Galilean relativity and Newton's laws. (However, such a "Maxwell aether" was later disproven; Newton's laws did, in fact, have to be replaced.)


title: Fundamental interaction

text: The Standard Model of particle physics was developed throughout the latter half of the 20th century. In the Standard Model, the electromagnetic, strong, and weak interactions associate with elementary particles, whose behaviours are modelled in quantum mechanics (QM). For predictive success with QM's probabilistic outcomes, particle physics conventionally models QM events across a field set to special relativity, altogether relativistic quantum field theory (QFT). Force particles, called gauge bosons—"force carriers" or "messenger particles" of underlying fields—interact with matter particles, called fermions. Everyday matter is atoms, composed of three fermion types: up-quarks and down-quarks constituting, as well as electrons orbiting, the atom's nucleus. Atoms interact, form molecules, and manifest further properties through electromagnetic interactions among their electrons absorbing and emitting photons, the electromagnetic field's force carrier, which if unimpeded traverse potentially infinite distance. Electromagnetism's QFT is quantum electrodynamics (QED).


title: Fundamental interaction

text: The force carriers of the weak interaction are the massive W and Z bosons. Electroweak theory (EWT) covers both electromagnetism and the weak interaction. At the high temperatures shortly after the Big Bang, the weak interaction, the electromagnetic interaction, and the Higgs boson were originally mixed components of a different set of ancient pre-symmetry-breaking fields. As the early universe cooled, these fields split into the long-range electromagnetic interaction, the short-range weak interaction, and the Higgs boson. In the Higgs mechanism, the Higgs field manifests Higgs bosons that interact with some quantum particles in a way that endows those particles with mass. The strong interaction, whose force carrier is the gluon, traversing minuscule distance among quarks, is modeled in quantum chromodynamics (QCD). EWT, QCD, and the Higgs mechanism comprise particle physics' Standard Model (SM). Predictions are usually made using calculational approximation methods, although such perturbation theory is inadequate to model some experimental observations (for instance bound states and solitons). Still, physicists widely accept the Standard Model as science's most experimentally confirmed theory.


title: Fundamental interaction

text: Beyond the Standard Model, some theorists work to unite the electroweak and strong interactions within a Grand Unified Theory (GUT). Some attempts at GUTs hypothesize "shadow" particles, such that every known matter particle associates with an undiscovered force particle, and vice versa, altogether supersymmetry (SUSY). Other theorists seek to quantize the gravitational field by the modelling behaviour of its hypothetical force carrier, the graviton and achieve quantum gravity (QG). One approach to QG is loop quantum gravity (LQG). Still other theorists seek both QG and GUT within one framework, reducing all four fundamental interactions to a Theory of Everything (ToE). The most prevalent aim at a ToE is string theory, although to model matter particles, it added SUSY to force particles—and so, strictly speaking, became superstring theory. Multiple, seemingly disparate superstring theories were unified on a backbone, M-theory. Theories beyond the Standard Model remain highly speculative, lacking great experimental support.


title: Fundamental interaction

text: In the conceptual model of fundamental interactions, matter consists of fermions, which carry properties called charges and spin ± (intrinsic angular momentum ±, where ħ is the reduced Planck constant). They attract or repel each other by exchanging bosons.


title: Fundamental interaction

text: The exchange of bosons always carries energy and momentum between the fermions, thereby changing their speed and direction. The exchange may also transport a charge between the fermions, changing the charges of the fermions in the process (e.g., turn them from one type of fermion to another). Since bosons carry one unit of angular momentum, the fermion's spin direction will flip from + to − (or vice versa) during such an exchange (in units of the reduced Planck's constant). Since such interactions result in a change in momentum, they can give rise to classical Newtonian forces. In quantum mechanics, physicists often use the terms "force" and "interaction" interchangeably; for example, the weak interaction is sometimes referred to as the "weak force".


title: Fundamental interaction

text: According to the present understanding, there are four fundamental interactions or forces: gravitation, electromagnetism, the weak interaction, and the strong interaction. Their magnitude and behaviour vary greatly, as described in the table below. Modern physics attempts to explain every observed physical phenomenon by these fundamental interactions. Moreover, reducing the number of different interaction types is seen as desirable. Two cases in point are the unification of:


title: Fundamental interaction

text: Both magnitude ("relative strength") and "range" of the associated potential, as given in the table, are meaningful only within a rather complex theoretical framework. The table below lists properties of a conceptual scheme that remains the subject of ongoing research.


title: Fundamental interaction

text: The modern (perturbative) quantum mechanical view of the fundamental forces other than gravity is that particles of matter (fermions) do not directly interact with each other, but rather carry a charge, and exchange virtual particles (gauge bosons), which are the interaction carriers or force mediators. For example, photons mediate the interaction of electric charges, and gluons mediate the interaction of color charges. The full theory includes perturbations beyond simply fermions exchanging bosons; these additional perturbations can involve bosons that exchange fermions, as well as the creation or destruction of particles: see Feynman diagrams for examples.


title: Fundamental interaction

text: "Gravitation" is by far the weakest of the four interactions at the atomic scale, where electromagnetic interactions dominate. But the idea that the weakness of gravity can easily be demonstrated by suspending a pin using a simple magnet (such as a refrigerator magnet) is fundamentally flawed. The only reason the magnet is able to hold the pin against the gravitational pull of the entire Earth is due to its relative proximity. There is clearly a short distance of separation between magnet and pin where a breaking point is reached, and due to the large mass of Earth this distance is quite small.


title: Fundamental interaction

text: Gravitation is the most important of the four fundamental forces for astronomical objects over astronomical distances for two reasons. First, gravitation has an infinite effective range, like electromagnetism but unlike the strong and weak interactions. Second, gravity always attracts and never repels; in contrast, astronomical bodies tend toward a near-neutral net electric charge, such that the attraction to one type of charge and the repulsion from the opposite charge mostly cancel each other out.


title: Fundamental interaction

text: Even though electromagnetism is far stronger than gravitation, electrostatic attraction is not relevant for large celestial bodies, such as planets, stars, and galaxies, simply because such bodies contain equal numbers of protons and electrons and so have a net electric charge of zero. Nothing "cancels" gravity, since it is only attractive, unlike electric forces which can be attractive or repulsive. On the other hand, all objects having mass are subject to the gravitational force, which only attracts. Therefore, only gravitation matters on the large-scale structure of the universe.


title: Fundamental interaction

text: The long range of gravitation makes it responsible for such large-scale phenomena as the structure of galaxies and black holes and it retards the expansion of the universe. Gravitation also explains astronomical phenomena on more modest scales, such as planetary orbits, as well as everyday experience: objects fall; heavy objects act as if they were glued to the ground, and animals can only jump so high.


title: Fundamental interaction

text: Gravitation was the first interaction to be described mathematically. In ancient times, Aristotle hypothesized that objects of different masses fall at different rates. During the Scientific Revolution, Galileo Galilei experimentally determined that this hypothesis was wrong under certain circumstances — neglecting the friction due to air resistance and buoyancy forces if an atmosphere is present (e.g. the case of a dropped air-filled balloon vs a water-filled balloon), all objects accelerate toward the Earth at the same rate. Isaac Newton's law of Universal Gravitation (1687) was a good approximation of the behaviour of gravitation. Our present-day understanding of gravitation stems from Einstein's General Theory of Relativity of 1915, a more accurate (especially for cosmological masses and distances) description of gravitation in terms of the geometry of spacetime.


title: Fundamental interaction

text: Merging general relativity and quantum mechanics (or quantum field theory) into a more general theory of quantum gravity is an area of active research. It is hypothesized that gravitation is mediated by a massless spin-2 particle called the graviton.


title: Fundamental interaction

text: Although general relativity has been experimentally confirmed (at least for weak fields, i.e. not black holes) on all but the smallest scales, there are Alternatives to general relativity. These theories must reduce to general relativity in some limit, and the focus of observational work is to establish limits on what deviations from general relativity are possible.


title: Fundamental interaction

text: Electromagnetism and weak interaction appear to be very different at everyday low energies. They can be modeled using two different theories. However, above unification energy, on the order of 100 GeV, they would merge into a single electroweak force.


title: Fundamental interaction

text: The electroweak theory is very important for modern cosmology, particularly on how the universe evolved. This is because shortly after the Big Bang, when the temperature was still above approximately 10 K, the electromagnetic force and the weak force were still merged as a combined electroweak force.


title: Fundamental interaction

text: For contributions to the unification of the weak and electromagnetic interaction between elementary particles, Abdus Salam, Sheldon Glashow and Steven Weinberg were awarded the Nobel Prize in Physics in 1979.


title: Fundamental interaction

text: Electromagnetism is the force that acts between electrically charged particles. This phenomenon includes the electrostatic force acting between charged particles at rest, and the combined effect of electric and magnetic forces acting between charged particles moving relative to each other.


title: Fundamental interaction

text: Electromagnetism has an infinite range like gravity, but is vastly stronger than it, and therefore describes several macroscopic phenomena of everyday experience such as friction, rainbows, lightning, and all human-made devices using electric current, such as television, lasers, and computers. Electromagnetism fundamentally determines all macroscopic, and many atomic-level, properties of the chemical elements, including all chemical bonding.


title: Fundamental interaction

text: of total electron charge. Thus, if we place two such jugs a meter apart, the electrons in one of the jugs repel those in the other jug with a force of


title: Fundamental interaction

text: This force is many times larger than the weight of the planet Earth. The atomic nuclei in one jug also repel those in the other with the same force. However, these repulsive forces are canceled by the attraction of the electrons in jug A with the nuclei in jug B and the attraction of the nuclei in jug A with the electrons in jug B, resulting in no net force. Electromagnetic forces are tremendously stronger than gravity but cancel out so that for large bodies gravity dominates.


title: Fundamental interaction

text: Electrical and magnetic phenomena have been observed since ancient times, but it was only in the 19th century James Clerk Maxwell discovered that electricity and magnetism are two aspects of the same fundamental interaction. By 1864, Maxwell's equations had rigorously quantified this unified interaction. Maxwell's theory, restated using vector calculus, is the classical theory of electromagnetism, suitable for most technological purposes.


title: Fundamental interaction

text: The constant speed of light in a vacuum (customarily described with a lowercase letter """") can be derived from Maxwell's equations, which are consistent with the theory of special relativity. Albert Einstein's 1905 theory of special relativity, however, which follows from the observation that the speed of light is constant no matter how fast the observer is moving, showed that the theoretical result implied by Maxwell's equations has profound implications far beyond electromagnetism on the very nature of time and space.


title: Fundamental interaction

text: In another work that departed from classical electro-magnetism, Einstein also explained the photoelectric effect by utilizing Max Planck's discovery that light was transmitted in 'quanta' of specific energy content based on the frequency, which we now call photons. Starting around 1927, Paul Dirac combined quantum mechanics with the relativistic theory of electromagnetism. Further work in the 1940s, by Richard Feynman, Freeman Dyson, Julian Schwinger, and Sin-Itiro Tomonaga, completed this theory, which is now called quantum electrodynamics, the revised theory of electromagnetism. Quantum electrodynamics and quantum mechanics provide a theoretical basis for electromagnetic behavior such as quantum tunneling, in which a certain percentage of electrically charged particles move in ways that would be impossible under the classical electromagnetic theory, that is necessary for everyday electronic devices such as transistors to function.


title: Fundamental interaction

text: The "weak interaction" or "weak nuclear force" is responsible for some nuclear phenomena such as beta decay. Electromagnetism and the weak force are now understood to be two aspects of a unified electroweak interaction — this discovery was the first step toward the unified theory known as the Standard Model. In the theory of the electroweak interaction, the carriers of the weak force are the massive gauge bosons called the W and Z bosons. The weak interaction is the only known interaction that does not conserve parity; it is left–right asymmetric. The weak interaction even violates CP symmetry but does conserve CPT.


title: Fundamental interaction

text: The "strong interaction", or "strong nuclear force", is the most complicated interaction, mainly because of the way it varies with distance. The nuclear force is powerfully attractive between nucleons at distances of about 1 femtometre (fm, or 10 metres), but it rapidly decreases to insignificance at distances beyond about 2.5 fm. At distances less than 0.7 fm, the nuclear force becomes repulsive. This repulsive component is responsible for the physical size of nuclei, since the nucleons can come no closer than the force allows.


title: Fundamental interaction

text: After the nucleus was discovered in 1908, it was clear that a new force, today known as the nuclear force, was needed to overcome the electrostatic repulsion, a manifestation of electromagnetism, of the positively charged protons. Otherwise, the nucleus could not exist. Moreover, the force had to be strong enough to squeeze the protons into a volume whose diameter is about 10 m, much smaller than that of the entire atom. From the short range of this force, Hideki Yukawa predicted that it was associated with a massive force particle, whose mass is approximately 100 MeV.


title: Fundamental interaction

text: The 1947 discovery of the pion ushered in the modern era of particle physics. Hundreds of hadrons were discovered from the 1940s to 1960s, and an extremely complicated theory of hadrons as strongly interacting particles was developed. Most notably:


title: Fundamental interaction

text: Murray Gell-Mann along with George Zweig first proposed fractionally charged quarks in 1961. Throughout the 1960s, different authors considered theories similar to the modern fundamental theory of quantum chromodynamics (QCD) as simple models for the interactions of quarks. The first to hypothesize the gluons of QCD were Moo-Young Han and Yoichiro Nambu, who introduced the quark color charge. Han and Nambu hypothesized that it might be associated with a force-carrying field. At that time, however, it was difficult to see how such a model could permanently confine quarks. Han and Nambu also assigned each quark color an integer electrical charge, so that the quarks were fractionally charged only on average, and they did not expect the quarks in their model to be permanently confined.


title: Fundamental interaction

text: In 1971, Murray Gell-Mann and Harald Fritzsch proposed that the Han/Nambu color gauge field was the correct theory of the short-distance interactions of fractionally charged quarks. A little later, David Gross, Frank Wilczek, and David Politzer discovered that this theory had the property of asymptotic freedom, allowing them to make contact with experimental evidence. They concluded that QCD was the complete theory of the strong interactions, correct at all distance scales. The discovery of asymptotic freedom led most physicists to accept QCD since it became clear that even the long-distance properties of the strong interactions could be consistent with experiment if the quarks are permanently confined: the strong force increases indefinitely with distance, trapping quarks inside the hadrons.


title: Fundamental interaction

text: Assuming that quarks are confined, Mikhail Shifman, Arkady Vainshtein and Valentine Zakharov were able to compute the properties of many low-lying hadrons directly from QCD, with only a few extra parameters to describe the vacuum. In 1980, Kenneth G. Wilson published computer calculations based on the first principles of QCD, establishing, to a level of confidence tantamount to certainty, that QCD will confine quarks. Since then, QCD has been the established theory of strong interactions.


title: Fundamental interaction

text: QCD is a theory of fractionally charged quarks interacting by means of 8 bosonic particles called gluons. The gluons also interact with each other, not just with the quarks, and at long distances the lines of force collimate into strings, loosely modeled by a linear potential, a constant attractive force. In this way, the mathematical theory of QCD not only explains how quarks interact over short distances but also the string-like behavior, discovered by Chew and Frautschi, which they manifest over longer distances.


title: Fundamental interaction

text: Nonetheless, although not a gauge interaction nor generated by any diffeomorphism symmetry, the Higgs field's cubic Yukawa coupling produces a weakly attractive fifth interaction. After spontaneous symmetry breaking via the Higgs mechanism, Yukawa terms remain of the form


title: Fundamental interaction

text: with Yukawa coupling formula_2, particle mass formula_3 (in eV), and Higgs vacuum expectation value . Hence coupled particles can exchange a virtual Higgs boson, yielding classical potentials of the form


title: Fundamental interaction

text: with Higgs mass . Because the reduced Compton wavelength of the Higgs boson is so small (, comparable to the W and Z bosons), this potential has an effective range of a few attometers. Between two electrons, it begins roughly 10 times weaker than the weak interaction, and grows exponentially weaker at non-zero distances.


title: Fundamental interaction

text: Numerous theoretical efforts have been made to systematize the existing four fundamental interactions on the model of electroweak unification.


title: Fundamental interaction

text: Grand Unified Theories (GUTs) are proposals to show that the three fundamental interactions described by the Standard Model are all different manifestations of a single interaction with symmetries that break down and create separate interactions below some extremely high level of energy. GUTs are also expected to predict some of the relationships between constants of nature that the Standard Model treats as unrelated, as well as predicting gauge coupling unification for the relative strengths of the electromagnetic, weak, and strong forces (this was, for example, verified at the Large Electron–Positron Collider in 1991 for supersymmetric theories).


title: Fundamental interaction

text: Theories of everything, which integrate GUTs with a quantum gravity theory face a greater barrier, because no quantum gravity theories, which include string theory, loop quantum gravity, and twistor theory, have secured wide acceptance. Some theories look for a graviton to complete the Standard Model list of force-carrying particles, while others, like loop quantum gravity, emphasize the possibility that time-space itself may have a quantum aspect to it.


title: Fundamental interaction

text: Some theories beyond the Standard Model include a hypothetical fifth force, and the search for such a force is an ongoing line of experimental physics research. In supersymmetric theories, some particles acquire their masses only through supersymmetry breaking effects and these particles, known as moduli, can mediate new forces. Another reason to look for new forces is the discovery that the expansion of the universe is accelerating (also known as dark energy), giving rise to a need to explain a nonzero cosmological constant, and possibly to other modifications of general relativity. Fifth forces have also been suggested to explain phenomena such as CP violations, dark matter, and dark flow.


title: Armadillidiidae

text: Armadillidiidae is a family of woodlice, a terrestrial crustacean group in the order Isopoda. Unlike members of some other woodlice families, members of this family can roll into a ball, an ability they share with the outwardly similar but unrelated pill millipedes and other animals. This ability gives woodlice in this family their common names of pill bugs or roly polies. Other common names include slaters, potato bugs, doodle bugs and cheeselogs. Most species are native to the Mediterranean Basin, while a few species have wider European distributions. The best-known species, "Armadillidium vulgare", was introduced to New England in the early 19th century and has become widespread throughout North America.


title: Armadillidiidae

text: Pill bugs in the family Armadillidiidae are able to form their bodies into a ball shape, in a process known as "conglobation". This behaviour is shared with pill millipedes (which are often confused with pill bugs), armadillos, and cuckoo wasps. It may be triggered by stimuli such as vibrations or pressure, and is a key defense against predation; it may also reduce respiratory water losses.


title: Armadillidiidae

text: The diet of pill bugs is largely made up of decaying or decomposed plant matter such as leaves, and to a lesser extent, wood fibers. Pill bugs will also eat living plants, especially in wet conditions, sometimes consuming leaves, stems, shoots, roots, tubers, and fruits. Pill bugs can be serious pests in certain agricultural systems, particularly in areas that are prone to heavy rains and flood conditions. Pill bugs will feed on numerous crop plants including corn, beans, squash, peas, melon, chard, beet, cucumber, potato, spinach, lettuce, and strawberry, with potential for significant yield loss in strawberry in particular. Some species of pill bugs are known to eat decaying animal flesh or feces. They will also eat shed snakeskin and dead bugs, if necessary.


title: Armadillidiidae

text: The family Armadillidiidae is differentiated from other woodlouse families by the two-segmented nature of the antennal flagellum, by the form of the uropods, and by the ability to roll into a ball.


title: Armadillidiidae

text: A 2022 study of myrmecophilous populations indicated that these represented a new species of "Cristarmadillidium", and three new species within a new genus, "Iberiarmadillidium".


title: History of artificial intelligence

text: The history of artificial intelligence (AI) began in antiquity, with myths, stories and rumors of artificial beings endowed with intelligence or consciousness by master craftsmen. The seeds of modern AI were planted by philosophers who attempted to describe the process of human thinking as the mechanical manipulation of symbols.This work culminated in the invention of the programmable digital computer in the 1940s, a machine based on the abstract essence of mathematical reasoning. This device and the ideas behind it inspired a handful of scientists to begin seriously discussing the possibility of building an electronic brain.


title: History of artificial intelligence

text: The field of AI research was founded at a workshop held on the campus of Dartmouth College, USA during the summer of 1956. Those who attended would become the leaders of AI research for decades. Many of them predicted that a machine as intelligent as a human being would exist in no more than a generation, and they were given millions of dollars to make this vision come true.


title: History of artificial intelligence

text: Eventually, it became obvious that commercial developers and researchers had grossly underestimated the difficulty of the project. In 1974, in response to the criticism from James Lighthill and ongoing pressure from congress, the U.S. and British Governments stopped funding undirected research into artificial intelligence, and the difficult years that followed would later be known as an "AI winter". Seven years later, a visionary initiative by the Japanese Government inspired governments and industry to provide AI with billions of dollars, but by the late 80s the investors became disillusioned and withdrew funding again.


title: History of artificial intelligence

text: Investment and interest in AI boomed in the first decades of the 21st century when machine learning was successfully applied to many problems in academia and industry due to new methods, the application of powerful computer hardware, and the collection of immense data sets.


title: History of artificial intelligence

text: In Greek Mythology, Talos was a giant constructed of bronze who acted as guardian for the island of Crete. He would throw boulders at the ships of invaders, and would complete 3 circuits around the island's perimeter daily. According to pseudo-Apollodorus' "Bibliotheke", Hephaestus forged Talos with the aid of a cyclops and presented the automaton as a gift to Minos. In the Argonautica, Jason and the Argonauts defeated him by way of a single plug near his foot which, once removed, allowed the vital ichor to flow out from his body and left him inanimate.


title: History of artificial intelligence

text: Pygmalion was a legendary king and sculptor of Greek Mythology, famously represented in Ovid’s "Metamorphoses". In the 10th book of Ovid’s narrative poem, Pygmalion becomes disgusted with women when he witnesses the way in which the Propoetides prostitute themselves. Despite this, he makes offerings at the temple of Venus asking the goddess to bring to him a woman just like a statue he carved. The earliest written account regarding golem-making is found in the writings of Eleazar ben Judah of Worms circa 12–13th century. During the Middle Ages, it was believed that the animation of a Golem could be achieved by insertion of a piece of paper with any of God’s names on it, into the mouth of the clay figure. Unlike legendary automata like Brazen Heads, a Golem was unable to speak.


title: History of artificial intelligence

text: In "Of the Nature of Things", written by the Swiss-born alchemist, Paracelsus, he describes a procedure which he claims can fabricate an "artificial man". By placing the "sperm of a man" in horse dung, and feeding it the "Arcanum of Mans blood" after 40 days, the concoction will become a living infant. "Takwin", the artificial creation of life, was a frequent topic of Ismaili alchemical manuscripts, especially those attributed to Jabir ibn Hayyan. Islamic alchemists attempted to create a broad range of life through their work, ranging from plants to animals. In Faust, The Second Part of the Tragedy by Johann Wolfgang von Goethe, an alchemically fabricated Homunculus, destined to live forever in the flask in which he was made, endeavors to be born into a full human body. Upon the initiation of this transformation, however, the flask shatters and the Homunculus dies.


title: History of artificial intelligence

text: By the 19th century, ideas about artificial men and thinking machines were developed in fiction, as in Mary Shelley's "Frankenstein" or Karel Čapek's "R.U.R. (Rossum's Universal Robots)",


title: History of artificial intelligence

text: and speculation, such as Samuel Butler's "Darwin among the Machines," and in real world instances, including Edgar Allan Poe's "Maelzel's Chess Player".


title: History of artificial intelligence

text: The oldest known automata were the sacred statues of ancient Egypt and Greece. The faithful believed that craftsman had imbued these figures with very real minds, capable of wisdom and emotion—Hermes Trismegistus wrote that "by discovering the true nature of the gods, man has been able to reproduce it."


title: History of artificial intelligence

text: During the early modern period, these legendary automata were said to possess the magical ability to answer questions put to them. The late medieval alchemist and scholar Roger Bacon was purported to have fabricated a brazen head, having developed a legend of having been a wizard. These legends were similar to the Norse myth of the Head of Mímir. According to legend, Mímir was known for his intellect and wisdom, and was beheaded in the Æsir-Vanir War. Odin is said to have "embalmed" the head with herbs and spoke incantations over it such that Mímir’s head remained able to speak wisdom to Odin. Odin then kept the head near him for counsel.


title: History of artificial intelligence

text: Artificial intelligence is based on the assumption that the process of human thought can be mechanized. The study of mechanical—or "formal"—reasoning has a long history. Chinese, Indian and Greek philosophers all developed structured methods of formal deduction in the first millennium BCE. Their ideas were developed over the centuries by philosophers such as Aristotle (who gave a formal analysis of the syllogism), Euclid (whose "Elements" was a model of formal reasoning), al-Khwārizmī (who developed algebra and gave his name to "algorithm") and European scholastic philosophers such as William of Ockham and Duns Scotus.


title: History of artificial intelligence

text: Spanish philosopher Ramon Llull (1232–1315) developed several "logical machines" devoted to the production of knowledge by logical means; Llull described his machines as mechanical entities that could combine basic and undeniable truths by simple logical operations, produced by the machine by mechanical meanings, in such ways as to produce all the possible knowledge. Llull's work had a great influence on Gottfried Leibniz, who redeveloped his ideas.


title: History of artificial intelligence

text: In the 17th century, Leibniz, Thomas Hobbes and René Descartes explored the possibility that all rational thought could be made as systematic as algebra or geometry. Hobbes famously wrote in "Leviathan": "reason is nothing but reckoning". Leibniz envisioned a universal language of reasoning, the "characteristica universalis", which would reduce argumentation to calculation so that "there would be no more need of disputation between two philosophers than between two accountants. For it would suffice to take their pencils in hand, down to their slates, and to say each other (with a friend as witness, if they liked): "Let us calculate"." These philosophers had begun to articulate the physical symbol system hypothesis that would become the guiding faith of AI research.


title: History of artificial intelligence

text: In the 20th century, the study of mathematical logic provided the essential breakthrough that made artificial intelligence seem plausible. The foundations had been set by such works as Boole's "The Laws of Thought" and Frege's "Begriffsschrift". Building on Frege's system, Russell and Whitehead presented a formal treatment of the foundations of mathematics in their masterpiece, the "Principia Mathematica" in 1913. Inspired by Russell's success, David Hilbert challenged mathematicians of the 1920s and 30s to answer this fundamental question: "can all of mathematical reasoning be formalized?"


title: History of artificial intelligence

text: His question was answered by Gödel's incompleteness proof, Turing's machine and Church's Lambda calculus.


title: History of artificial intelligence

text: Their answer was surprising in two ways. First, they proved that there were, in fact, limits to what mathematical logic could accomplish. But second (and more important for AI) their work suggested that, within these limits, "any" form of mathematical reasoning could be mechanized. The Church-Turing thesis implied that a mechanical device, shuffling symbols as simple as 0 and 1, could imitate any conceivable process of mathematical deduction. The key insight was the Turing machine—a simple theoretical construct that captured the essence of abstract symbol manipulation. This invention would inspire a handful of scientists to begin discussing the possibility of thinking machines.


title: History of artificial intelligence

text: Calculating machines were built in antiquity and improved throughout history by many mathematicians, including (once again) philosopher Gottfried Leibniz. In the early 19th century, Charles Babbage designed a programmable computer (the Analytical Engine), although it was never built. Ada Lovelace speculated that the machine "might compose elaborate and scientific pieces of music of any degree of complexity or extent". (She is often credited as the first programmer because of a set of notes she wrote that completely detail a method for calculating Bernoulli numbers with the Engine.)


title: History of artificial intelligence

text: Following Babbage, although at first unaware of his earlier work, was Percy Ludgate, a clerk to a corn merchant in Dublin, Ireland. He independently designed a programmable mechanical computer, which he described in a work that was published in 1909.


title: History of artificial intelligence

text: Two other inventors, Leonardo Torres y Quevedo and Vannevar Bush, also did follow on research based on Babbage's work.


title: History of artificial intelligence

text: In his "Essays on Automatics" (1913) Torres designed a Babbage type of calculating machine that used electromechanical parts which included floating point number representations and built a prototype in 1920. Torres is also known for having built in 1912 an autonomous machine capable of playing chess, "El Ajedrecista". As opposed to the human-operated The Turk and Ajeeb, "El Ajedrecista" (The Chessplayer) was a true automaton which could play chess without human guidance. It only played an endgame with three chess pieces, automatically moving a white king and a rook to checkmate the black king moved by a human opponent.


title: History of artificial intelligence

text: Vannevar Bush's paper "Instrumental Analysis" (1936) discussed using existing IBM punch card machines to implement Babbage's design. In the same year he started the Rapid Arithmetical Machine project to investigate the problems of constructing an electronic digital computer.


title: History of artificial intelligence

text: The first modern computers were the massive code breaking machines of the Second World War (such as Z3, ENIAC and Colossus). The latter two of these machines were based on the theoretical foundation laid by Alan Turing and developed by John von Neumann.


title: History of artificial intelligence

text: In the 1940s and 50s, a handful of scientists from a variety of fields (mathematics, psychology, engineering, economics and political science) began to discuss the possibility of creating an artificial brain. The field of artificial intelligence research was founded as an academic discipline in 1956.


title: History of artificial intelligence

text: The earliest research into thinking machines was inspired by a confluence of ideas that became prevalent in the late 1930s, 1940s, and early 1950s. Recent research in neurology had shown that the brain was an electrical network of neurons that fired in all-or-nothing pulses. Norbert Wiener's cybernetics described control and stability in electrical networks. Claude Shannon's information theory described digital signals (i.e., all-or-nothing signals). Alan Turing's theory of computation showed that any form of computation could be described digitally. The close relationship between these ideas suggested that it might be possible to construct an electronic brain.


title: History of artificial intelligence

text: Examples of work in this vein includes robots such as W. Grey Walter's turtles and the Johns Hopkins Beast. These machines did not use computers, digital electronics or symbolic reasoning; they were controlled entirely by analog circuitry.


title: History of artificial intelligence

text: Walter Pitts and Warren McCulloch analyzed networks of idealized artificial neurons and showed how they might perform simple logical functions in 1943. They were the first to describe what later researchers would call a neural network. One of the students inspired by Pitts and McCulloch was a young Marvin Minsky, then a 24-year-old graduate student. In 1951 (with Dean Edmonds) he built the first neural net machine, the SNARC.


title: History of artificial intelligence

text: In 1950 Alan Turing published a landmark paper in which he speculated about the possibility of creating machines that think.


title: History of artificial intelligence

text: He noted that "thinking" is difficult to define and devised his famous Turing Test. If a machine could carry on a conversation (over a teleprinter) that was indistinguishable from a conversation with a human being, then it was reasonable to say that the machine was "thinking". This simplified version of the problem allowed Turing to argue convincingly that a "thinking machine" was at least "plausible" and the paper answered all the most common objections to the proposition. The Turing Test was the first serious proposal in the philosophy of artificial intelligence.


title: History of artificial intelligence

text: In 1951, using the Ferranti Mark 1 machine of the University of Manchester, Christopher Strachey wrote a checkers program and Dietrich Prinz wrote one for chess. Arthur Samuel's checkers program, developed in the middle 50s and early 60s, eventually achieved sufficient skill to challenge a respectable amateur. Game AI would continue to be used as a measure of progress in AI throughout its history.


title: History of artificial intelligence

text: When access to digital computers became possible in the middle fifties, a few scientists instinctively recognized that a machine that could manipulate numbers could also manipulate symbols and that the manipulation of symbols could well be the essence of human thought. This was a new approach to creating thinking machines.


title: History of artificial intelligence

text: In 1955, Allen Newell and (future Nobel Laureate) Herbert A. Simon created the "Logic Theorist" (with help from J. C. Shaw). The program would eventually prove 38 of the first 52 theorems in Russell and Whitehead's "Principia Mathematica", and find new and more elegant proofs for some.


title: History of artificial intelligence

text: Simon said that they had "solved the venerable mind/body problem, explaining how a system composed of matter can have the properties of mind."


title: History of artificial intelligence

text: was organized by Marvin Minsky, John McCarthy and two senior scientists: Claude Shannon and Nathan Rochester of IBM. The proposal for the conference included this assertion: "every aspect of learning or any other feature of intelligence can be so precisely described that a machine can be made to simulate it".


title: History of artificial intelligence

text: The participants included Ray Solomonoff, Oliver Selfridge, Trenchard More, Arthur Samuel, Allen Newell and Herbert A. Simon, all of whom would create important programs during the first decades of AI research.


title: History of artificial intelligence

text: At the conference Newell and Simon debuted the "Logic Theorist" and McCarthy persuaded the attendees to accept "Artificial Intelligence" as the name of the field.


title: History of artificial intelligence

text: The 1956 Dartmouth conference was the moment that AI gained its name, its mission, its first success and its major players, and is widely considered the birth of AI. The term "Artificial Intelligence" was chosen by McCarthy to avoid associations with cybernetics and connections with the influential cyberneticist Norbert Wiener.


title: History of artificial intelligence

text: The programs developed in the years after the Dartmouth Workshop were, to most people, simply "astonishing": computers were solving algebra word problems, proving theorems in geometry and learning to speak English. Few at the time would have believed that such "intelligent" behavior by machines was possible at all. Researchers expressed an intense optimism in private and in print, predicting that a fully intelligent machine would be built in less than 20 years. Government agencies like DARPA poured money into the new field.


title: History of artificial intelligence

text: There were many successful programs and new directions in the late 50s and 1960s. Among the most influential were these:


title: History of artificial intelligence

text: Many early AI programs used the same basic algorithm. To achieve some goal (like winning a game or proving a theorem), they proceeded step by step towards it (by making a move or a deduction) as if searching through a maze, backtracking whenever they reached a dead end. This paradigm was called "reasoning as search".


title: History of artificial intelligence

text: The principal difficulty was that, for many problems, the number of possible paths through the "maze" was simply astronomical (a situation known as a "combinatorial explosion"). Researchers would reduce the search space by using heuristics or "rules of thumb" that would eliminate those paths that were unlikely to lead to a solution.


title: History of artificial intelligence

text: Newell and Simon tried to capture a general version of this algorithm in a program called the "General Problem Solver". Other "searching" programs were able to accomplish impressive tasks like solving problems in geometry and algebra, such as Herbert Gelernter's Geometry Theorem Prover (1958) and SAINT, written by Minsky's student James Slagle (1961). Other programs searched through goals and subgoals to plan actions, like the STRIPS system developed at Stanford to control the behavior of their robot Shakey.


title: History of artificial intelligence

text: An important goal of AI research is to allow computers to communicate in natural languages like English. An early success was Daniel Bobrow's program STUDENT, which could solve high school algebra word problems.


title: History of artificial intelligence

text: A semantic net represents concepts (e.g. "house","door") as nodes and relations among concepts (e.g. "has-a") as links between the nodes. The first AI program to use a semantic net was written by Ross Quillian and the most successful (and controversial) version was Roger Schank's Conceptual dependency theory.


title: History of artificial intelligence

text: Joseph Weizenbaum's ELIZA could carry out conversations that were so realistic that users occasionally were fooled into thinking they were communicating with a human being and not a program (See ELIZA effect). But in fact, ELIZA had no idea what she was talking about. She simply gave a canned response or repeated back what was said to her, rephrasing her response with a few grammar rules. ELIZA was the first chatterbot.


title: History of artificial intelligence

text: In the late 60s, Marvin Minsky and Seymour Papert of the MIT AI Laboratory proposed that AI research should focus on artificially simple situations known as micro-worlds. They pointed out that in successful sciences like physics, basic principles were often best understood using simplified models like frictionless planes or perfectly rigid bodies. Much of the research focused on a "blocks world," which consists of colored blocks of various shapes and sizes arrayed on a flat surface.


title: History of artificial intelligence

text: This paradigm led to innovative work in machine vision by Gerald Sussman (who led the team), Adolfo Guzman, David Waltz (who invented "constraint propagation"), and especially Patrick Winston. At the same time, Minsky and Papert built a robot arm that could stack blocks, bringing the blocks world to life. The crowning achievement of the micro-world program was Terry Winograd's SHRDLU. It could communicate in ordinary English sentences, plan operations and execute them.


title: History of artificial intelligence

text: In Japan, Waseda University initiated the WABOT project in 1967, and in 1972 completed the WABOT-1, the world's first full-scale "intelligent" humanoid robot, or android. Its limb control system allowed it to walk with the lower limbs, and to grip and transport objects with hands, using tactile sensors. Its vision system allowed it to measure distances and directions to objects using external receptors, artificial eyes and ears. And its conversation system allowed it to communicate with a person in Japanese, with an artificial mouth.


title: History of artificial intelligence

text: In June 1963, MIT received a $2.2 million grant from the newly created Advanced Research Projects Agency (later known as DARPA). The money was used to fund project MAC which subsumed the "AI Group" founded by Minsky and McCarthy five years earlier. DARPA continued to provide three million dollars a year until the 70s.


title: History of artificial intelligence

text: DARPA made similar grants to Newell and Simon's program at CMU and to the Stanford AI Project (founded by John McCarthy in 1963). Another important AI laboratory was established at Edinburgh University by Donald Michie in 1965.


title: History of artificial intelligence

text: These four institutions would continue to be the main centers of AI research (and funding) in academia for many years.


title: History of artificial intelligence

text: The money was proffered with few strings attached: J. C. R. Licklider, then the director of ARPA, believed that his organization should "fund people, not projects!" and allowed researchers to pursue whatever directions might interest them. This created a freewheeling atmosphere at MIT that gave birth to the hacker culture, but this "hands off" approach would not last.


title: History of artificial intelligence

text: In the 1970s, AI was subject to critiques and financial setbacks. AI researchers had failed to appreciate the difficulty of the problems they faced. Their tremendous optimism had raised expectations impossibly high, and when the promised results failed to materialize, funding for AI disappeared. At the same time, the field of connectionism (or neural nets) was shut down almost completely for 10 years by Marvin Minsky's devastating criticism of perceptrons.


title: History of artificial intelligence

text: Despite the difficulties with public perception of AI in the late 70s, new ideas were explored in logic programming, commonsense reasoning and many other areas.


title: History of artificial intelligence

text: In the early seventies, the capabilities of AI programs were limited. Even the most impressive could only handle trivial versions of the problems they were supposed to solve; all the programs were, in some sense, "toys". AI researchers had begun to run into several fundamental limits that could not be overcome in the 1970s. Although some of these limits would be conquered in later decades, others still stymie the field to this day.


title: History of artificial intelligence

text: The agencies which funded AI research (such as the British government, DARPA and NRC) became frustrated with the lack of progress and eventually cut off almost all funding for undirected research into AI. The pattern began as early as 1966 when the ALPAC report appeared criticizing machine translation efforts. After spending 20 million dollars, the NRC ended all support.


title: History of artificial intelligence

text: In 1973, the Lighthill report on the state of AI research in England criticized the utter failure of AI to achieve its "grandiose objectives" and led to the dismantling of AI research in that country.


title: History of artificial intelligence

text: DARPA was deeply disappointed with researchers working on the Speech Understanding Research program at CMU and canceled an annual grant of three million dollars.


title: History of artificial intelligence

text: Hans Moravec blamed the crisis on the unrealistic predictions of his colleagues. "Many researchers were caught up in a web of increasing exaggeration."


title: History of artificial intelligence

text: However, there was another issue: since the passage of the Mansfield Amendment in 1969, DARPA had been under increasing pressure to fund "mission-oriented direct research, rather than basic undirected research". Funding for the creative, freewheeling exploration that had gone on in the 60s would not come from DARPA. Instead, the money was directed at specific projects with clear objectives, such as autonomous tanks and battle management systems.


title: History of artificial intelligence

text: Several philosophers had strong objections to the claims being made by AI researchers. One of the earliest was John Lucas, who argued that Gödel's incompleteness theorem showed that a formal system (such as a computer program) could never see the truth of certain statements, while a human being could. Hubert Dreyfus ridiculed the broken promises of the 1960s and critiqued the assumptions of AI, arguing that human reasoning actually involved very little "symbol processing" and a great deal of embodied, instinctive, unconscious "know how". John Searle's Chinese Room argument, presented in 1980, attempted to show that a program could not be said to "understand" the symbols that it uses (a quality called "intentionality"). If the symbols have no meaning for the machine, Searle argued, then the machine can not be described as "thinking".


title: History of artificial intelligence

text: These critiques were not taken seriously by AI researchers, often because they seemed so far off the point. Problems like intractability and commonsense knowledge seemed much more immediate and serious. It was unclear what difference "know how" or "intentionality" made to an actual computer program. Minsky said of Dreyfus and Searle "they misunderstand, and should be ignored." Dreyfus, who taught at MIT, was given a cold shoulder: he later said that AI researchers "dared not be seen having lunch with me." Joseph Weizenbaum, the author of ELIZA, felt his colleagues' treatment of Dreyfus was unprofessional and childish. Although he was an outspoken critic of Dreyfus' positions, he "deliberately made it plain that theirs was not the way to treat a human being."


title: History of artificial intelligence

text: Weizenbaum began to have serious ethical doubts about AI when Kenneth Colby wrote a "computer program which can conduct psychotherapeutic dialogue" based on ELIZA. Weizenbaum was disturbed that Colby saw a mindless program as a serious therapeutic tool. A feud began, and the situation was not helped when Colby did not credit Weizenbaum for his contribution to the program. In 1976, Weizenbaum published "Computer Power and Human Reason" which argued that the misuse of artificial intelligence has the potential to devalue human life.


title: History of artificial intelligence

text: A perceptron was a form of neural network introduced in 1958 by Frank Rosenblatt, who had been a schoolmate of Marvin Minsky at the Bronx High School of Science. Like most AI researchers, he was optimistic about their power, predicting that "perceptron may eventually be able to learn, make decisions, and translate languages." An active research program into the paradigm was carried out throughout the 1960s but came to a sudden halt with the publication of Minsky and Papert's 1969 book "Perceptrons". It suggested that there were severe limitations to what perceptrons could do and that Frank Rosenblatt's predictions had been grossly exaggerated. The effect of the book was devastating: virtually no research at all was done in connectionism for 10 years. Eventually, a new generation of researchers would revive the field and thereafter it would become a vital and useful part of artificial intelligence. Rosenblatt would not live to see this, as he died in a boating accident shortly after the book was published.


title: History of artificial intelligence

text: Logic was introduced into AI research as early as 1959, by John McCarthy in his Advice Taker proposal.


title: History of artificial intelligence

text: In 1963, J. Alan Robinson had discovered a simple method to implement deduction on computers, the resolution and unification algorithm. However, straightforward implementations, like those attempted by McCarthy and his students in the late 1960s, were especially intractable: the programs required astronomical numbers of steps to prove simple theorems. A more fruitful approach to logic was developed in the 1970s by Robert Kowalski at the University of Edinburgh, and soon this led to the collaboration with French researchers Alain Colmerauer and Philippe Roussel who created the successful logic programming language Prolog.


title: History of artificial intelligence

text: Prolog uses a subset of logic (Horn clauses, closely related to "rules" and "production rules") that permit tractable computation. Rules would continue to be influential, providing a foundation for Edward Feigenbaum's expert systems and the continuing work by Allen Newell and Herbert A. Simon that would lead to Soar and their unified theories of cognition.


title: History of artificial intelligence

text: Critics of the logical approach noted, as Dreyfus had, that human beings rarely used logic when they solved problems. Experiments by psychologists like Peter Wason, Eleanor Rosch, Amos Tversky, Daniel Kahneman and others provided proof.


title: History of artificial intelligence

text: McCarthy responded that what people do is irrelevant. He argued that what is really needed are machines that can solve problems—not machines that think as people do.


title: History of artificial intelligence

text: Among the critics of McCarthy's approach were his colleagues across the country at MIT. Marvin Minsky, Seymour Papert and Roger Schank were trying to solve problems like "story understanding" and "object recognition" that "required" a machine to think like a person. In order to use ordinary concepts like "chair" or "restaurant" they had to make all the same illogical assumptions that people normally made. Unfortunately, imprecise concepts like these are hard to represent in logic. Gerald Sussman observed that "using precise language to describe essentially imprecise concepts doesn't make them any more precise." Schank described their "anti-logic" approaches as "scruffy", as opposed to the "neat" paradigms used by McCarthy, Kowalski, Feigenbaum, Newell and Simon.


title: History of artificial intelligence

text: In 1975, in a seminal paper, Minsky noted that many of his fellow "scruffy" researchers were using the same kind of tool: a framework that captures all our common sense assumptions about something. For example, if we use the concept of a bird, there is a constellation of facts that immediately come to mind: we might assume that it flies, eats worms and so on. We know these facts are not always true and that deductions using these facts will not be "logical", but these structured sets of assumptions are part of the "context" of everything we say and think. He called these structures "frames". Schank used a version of frames he called "scripts" to successfully answer questions about short stories in English.


title: History of artificial intelligence

text: In the 1980s a form of AI program called "expert systems" was adopted by corporations around the world and knowledge became the focus of mainstream AI research. In those same years, the Japanese government aggressively funded AI with its fifth generation computer project. Another encouraging event in the early 1980s was the revival of connectionism in the work of John Hopfield and David Rumelhart. Once again, AI had achieved success.


title: History of artificial intelligence

text: An expert system is a program that answers questions or solves problems about a specific domain of knowledge, using logical rules that are derived from the knowledge of experts. The earliest examples were developed by Edward Feigenbaum and his students. Dendral, begun in 1965, identified compounds from spectrometer readings. MYCIN, developed in 1972, diagnosed infectious blood diseases. They demonstrated the feasibility of the approach.


title: History of artificial intelligence

text: Expert systems restricted themselves to a small domain of specific knowledge (thus avoiding the commonsense knowledge problem) and their simple design made it relatively easy for programs to be built and then modified once they were in place. All in all, the programs proved to be "useful": something that AI had not been able to achieve up to this point.


title: History of artificial intelligence

text: In 1980, an expert system called XCON was completed at CMU for the Digital Equipment Corporation. It was an enormous success: it was saving the company 40 million dollars annually by 1986. Corporations around the world began to develop and deploy expert systems and by 1985 they were spending over a billion dollars on AI, most of it to in-house AI departments. An industry grew up to support them, including hardware companies like Symbolics and Lisp Machines and software companies such as IntelliCorp and Aion.