title: Edible seaweed

text: Seaweed is also processed into noodles by residents of Tiwi, Albay, which can be cooked into pancit canton, pancit luglug, spaghetti or carbonara. such as being rich in calcium, magnesium and iodine.


title: AFL–NFL merger

text: The AFL–NFL merger was the merger of the two major professional American football leagues in the United States at the time: the National Football League (NFL) and the American Football League (AFL). It paved the way for the combined league, which retained the "National Football League" name and logo, to become the most popular sports league in the United States. The merger was announced on the evening of June 8, 1966. Under the merger agreement, the leagues maintained separate regular-season schedules for the next four seasons—from 1966 through 1969—and then officially merged before the 1970 season to form one league with two conferences.


title: AFL–NFL merger

text: Following its inception in 1920, the NFL fended off several rival leagues. Before 1960, its most important rival was the All-America Football Conference (AAFC), which began play in 1946. The AAFC differed from the NFL in several ways. Despite relatively strong backing at the league's inception, it ultimately proved an unsustainable venture. The AAFC's most serious weakness resulted from its refusal to implement an initial draft; this caused a massive lack of competitive balance, and resulted in the league's strongest team (the Cleveland Browns) dominating the league and becoming perennial champions.


title: AFL–NFL merger

text: Due to the AAFC's poor financial situation, the league disbanded after the 1949 season. Three AAFC teams—the Cleveland Browns, the San Francisco 49ers, and the original version of the Baltimore Colts—were absorbed into the NFL in 1950. The league was briefly known as the "National-American Football League" during the offseason, but reverted to the traditional name of "National Football League" by the time the 1950 season began. The Browns went on to shock NFL loyalists by dominating the older league and winning the championship in their first NFL season, thus proving themselves to be among the best professional football teams of that time.


title: AFL–NFL merger

text: After the NFL absorbed the AAFC, it had no other rival US leagues throughout the 1950s. The only other professional gridiron football leagues then in operation were in Canada (the leagues that would merge to form the present-day Canadian Football League in 1958). The Interprovincial Rugby Football Union (forerunner of the CFL's East Division) received some attention from US football fans after it secured a broadcasting contract with NBC (the AFL's future television partners).


title: AFL–NFL merger

text: During the 1950s the Eastern Canadian season started at around the same time as the NFL's; Canadian teams at this time typically played two games per week so as to finish the season before the harsh Canadian winter set in. This arrangement allowed for NFL teams to travel north of the border for preseason contests with the CFL's Eastern clubs. NFL teams won most of these contests, often by large scorelines. The other major Canadian league, the Western Interprovincial Football Union (forerunner of the CFL's West Division) was mostly ignored by the NFL, partly because its teams were regarded as inferior to those in Eastern Canada, but mainly because rail travel to Western Canada was infeasible for a preseason game (air travel remained uncommon). As a result, the Western Conference was already moving toward an earlier start to its season.


title: AFL–NFL merger

text: All of the professional leagues, including the NFL, derived most of their revenue from ticket sales. Although the NFL dominated the game financially, their advantage was modest by modern standards. The Canadian league enforced strict limits on the number of American players on their rosters, while the popularity of ice hockey in Canada limited the number of talented Canadian athletes that chose to play football. Therefore, NFL teams could retain their dominance on the field without needing to substantially out-spend the Canadian teams. In the absence of a players' labor union (the National Football League Players Association was founded in 1956 but was initially ineffective) or a competing US league, there was little pressure to pay players high salaries. NFL team owners spent as little as possible on players, to maximize their profit.


title: AFL–NFL merger

text: In 1959, Lamar Hunt, son of Texas oil magnate H. L. Hunt, attempted to either gain ownership of the Chicago Cardinals with Bud Adams and move them to Dallas, or own an NFL expansion franchise in Dallas. In 1959, the NFL had only two teams that were south of Washington, D.C. and west of Chicago: the San Francisco 49ers and the Los Angeles Rams, both in California. The league, however, was not interested in expansion at the time. Rebuffed in his attempts to gain at least part-ownership in an NFL team, Hunt conceived the idea of a rival professional football league, the "American Football League". In September 1959, Hunt was approached by the NFL about an expansion team in Dallas, but by then Hunt was only interested in the AFL.


title: AFL–NFL merger

text: The new league had six franchises by August 1959 and eight by the time of its first opening day in 1960: Boston (Patriots), Buffalo (Bills), New York City (Titans), Houston (Oilers), Denver (Broncos), Dallas (Texans), Oakland (Raiders), and Los Angeles (Chargers). While the Los Angeles, New York, Oakland, and Dallas teams shared media markets with NFL teams (the Rams, Giants, 49ers, and the expansion Dallas Cowboys, respectively), the other four teams (Boston, Buffalo, Denver, and Houston) widened the nation's exposure to professional football by serving markets that had no NFL team. In the following years, this additional exposure was widened via the relocation of two of the original eight franchises (the Chargers to San Diego in 1961 and the Texans to Kansas City in 1963), and the addition of two expansion franchises (the Miami Dolphins and Cincinnati Bengals).


title: AFL–NFL merger

text: From small colleges and predominantly black colleges (a source mainly ignored by the NFL), the AFL signed stars such as Elbert Dubenion (Bluffton), Lionel Taylor (New Mexico Highlands), Tom Sestak (McNeese State), Charlie Tolar and Charlie Hennigan (Northwestern State of Louisiana), Abner Haynes (North Texas State), and a host of others. From major colleges, it signed talented players like LSU's Heisman Trophy winner Billy Cannon, Arkansas's Lance Alworth, Notre Dame's Daryle Lamonica, Kansas' John Hadl, Alabama's Joe Namath, and many more. The AFL also signed players the NFL had given up on: so-called "NFL rejects" who turned out to be superstars that the NFL had mis-evaluated. These included Jack Kemp, Babe Parilli, George Blanda, Ron McDole, Art Powell, John Tracey, Don Maynard, and Len Dawson. In 1960, the AFL's first year, its teams signed half of the NFL's first-round draft choices.


title: AFL–NFL merger

text: The AFL introduced many policies and rules to professional football which the NFL later adopted, including:


title: AFL–NFL merger

text: At first, the NFL ignored the AFL and its eight teams, assuming the AFL would consist of players who could not earn a contract in the NFL, and that fans of professional football would not waste their time watching them when they could watch the NFL. The NFL also had the media advantage: for example, in the 1960s, "Sports Illustrated"s lead football writer was Tex Maule, who previously worked with NFL commissioner Pete Rozelle when Rozelle was the general manager of the L.A. Rams and Maule was the team's public relations director; Maule "was certainly an NFL loyalist", and several sports reporters took his deprecatory columns about the AFL as fact. Another example was Dallas Cowboys general manager Tex Schramm, a close friend of Rozelle (Schramm hired Rozelle as Rams' GM), who was influential in NFL coverage by its national TV partner, CBS, including the network's employment of former NFL players as game announcers and the absence of AFL scores and reports on the network.


title: AFL–NFL merger

text: Nevertheless, the AFL enjoyed one critical advantage over its established rival, which was that its owners on average were wealthier than their NFL counterparts. With a few notable exceptions such as the notorious Harry Wismer in New York, Hunt had successfully recruited owners who not only had deep pockets, but more importantly, unlike earlier leagues, most AFL owners had the patience and willingness to absorb the inevitable financial losses of the fledgling league's early years. Therefore, in spite of the bad press, and unlike the NFL's previous rivals, the AFL was able to survive and grow, and began to prosper in the mid-1960s after the relocation of the Chargers and Texans to non-NFL markets, the sale and rebranding of the New York Titans (to the Jets), and the Jets' signing of University of Alabama quarterback Joe Namath to an unprecedented $427,000 contract. The league's financial survival was further buoyed by NBC's $36 million, five-year contract to televise AFL games beginning in 1965.


title: AFL–NFL merger

text: As the rivalry between the leagues intensified, both leagues entered into a massive bidding war over the top college prospects, paying huge amounts of money to unproven rookies in order to outbid each other for the best players coming out of college. The bidding wars escalated in the mid-1960s, with the respective drafts held on the same day in the late fall. Because of the intense competition, teams often drafted players that they thought had a good chance of signing, instead of selecting the best available players. For example, 1965 Heisman Trophy winner Mike Garrett, a running back from USC in Los Angeles, was expected to sign with an NFL team, so he was not taken in the 1966 AFL draft until the 20th (final) round by the Kansas City Chiefs. In the 1966 NFL Draft, he was taken by the Los Angeles Rams with the 18th overall selection. Garrett surprisingly shunned the NFL and signed with Kansas City; he helped lead them to the AFL title as a rookie. The previous year, the Chiefs used their first round pick on Gale Sayers, who signed with the NFL's Chicago Bears.


title: AFL–NFL merger

text: By contrast, many NFL owners had comparatively little wealth outside the value of their respective franchises. The NFL consistently outdrew the AFL at the gate, especially in the AFL's first few seasons, thus ensuring that the older league's franchises remained considerably more lucrative enterprises compared to their AFL rivals. Nevertheless, NFL owners knew they did not have unlimited resources to wage a protracted bidding war with the AFL. Moreover, owners in both leagues feared that the reserve clause written into the standard players' contracts of both leagues would not survive a legal challenge. These fears proved well-founded since after the merger the upstart World Hockey Association (which unlike the AFL chose to challenge the reserve clause enforced by its established rival) ultimately prevailed in court.


title: AFL–NFL merger

text: National Football League teams had long adhered to the practice of drafting for and retaining the NFL rights to players who signed with the CFL and other leagues. This policy ensured, for example, that if a Canadian Football League player developed into a star, only one particular NFL team would have the right to try and sign him. This ensured that NFL teams did not become embroiled among themselves in costly bidding wars for top free agents. Once the American Football League commenced operations, NFL teams extended this policy to cover AFL players as well, and the AFL promptly reciprocated the arrangement. This arrangement soon evolved into a gentlemen's agreement between the two U.S. leagues — once a player signed with a team, be it from the AFL or NFL, teams in both leagues were expected to honor each other's player contracts in their entirety (including the respective reserve clauses) and not sign players who were under contract with a team in the rival league.


title: AFL–NFL merger

text: This unwritten agreement was broken in May 1966 when the NFL's New York Giants signed Pete Gogolak, the first professional soccer-style placekicker, who had played out his option in 1965 with the AFL's Buffalo Bills. The NFL's breach of trust resulted in retaliation by the AFL: Oakland Raiders co-owner Al Davis took over as AFL Commissioner in April 1966, and he stepped up the bidding war after the Gogolak transfer, signing notable NFL players, including John Brodie Mike Ditka, and Roman Gabriel to contracts with AFL teams, but after the merger agreement in June, they wound up staying in the older league. Both leagues spent a combined $7 million signing their 1966 draft picks.


title: AFL–NFL merger

text: Contrary to common belief, it was not the AFL, but the NFL that initiated discussions for a merger between the two leagues, as it was fearful that Davis' "take no prisoners" tactics would seriously diminish the older league's profitability and/or drastically reduce its talent base. Tex Schramm, the general manager of the NFL's Dallas Cowboys since 1960, secretly contacted AFL owners, led by Lamar Hunt of Kansas City, and asked if they were interested in a merger. The talks were conducted without the knowledge of Davis, the new AFL commissioner. On the evening of June 8, 1966, the collaborators announced a merger agreement in New York. Under the agreement:


title: AFL–NFL merger

text: Following the agreement, American Football League owners created the office of AFL "President" with a mandate to administer the league's day-to-day business in a semi-autonomous manner, much like the way the constituent leagues of Major League Baseball operated at the time. The owners had hoped Davis would continue to serve in that role, but Davis (already furious with the owners of both leagues for negotiating a merger without consulting him) flatly refused to consider serving as a subordinate to Pete Rozelle. After Davis resigned as AFL Commissioner on July 25, 1966, Milt Woodard (who was assistant commissioner under the original commissioner Joe Foss and Davis) was appointed to serve as President of the AFL.


title: AFL–NFL merger

text: Although Pete Rozelle had not initiated the merger negotiations, he quickly endorsed the agreement and remained in his post as NFL Commissioner. Although he was not formally invested with any new title(s), Rozelle was often referred to as the "football commissioner" or "commissioner of football" in the media during the four years following the merger agreement. The pre-existing office of "NFL President" continued effectively unchanged following the agreement. Then occupied by Cleveland Browns owner Art Modell, the NFL presidency was (both before and after the merger agreement) essentially an honorary title that operated in a manner similar to the way in which the league presidencies of MLB operate in the 21st century.


title: AFL–NFL merger

text: Implementation of the merger depended on the passage of a law by the 89th U.S. Congress, exempting the merged league from antitrust law sanctions. When NFL Commissioner Rozelle and other professional football executives appeared before the Congress' Subcommittee on Antitrust, chaired by New York Representative Emanuel Celler, three points were repeatedly made:


title: AFL–NFL merger

text: In October, Congress passed the new law to permit the merger to proceed. The terms of the merger called for the NFL and AFL to add one team each prior to the 1970 season. Louisiana Representative Hale Boggs and Senator Russell Long were instrumental in passage of the new law, and in return, Rozelle approved creation of the expansion New Orleans Saints franchise less than one month after the bill was signed into law by President Lyndon B. Johnson.


title: AFL–NFL merger

text: The tenth and final AFL franchise was awarded to former Cleveland Browns owner and coach Paul Brown downstate in Cincinnati. Brown had been seeking a way back into the NFL after being forced out of the Browns organization by Modell. Brown had not been a supporter of the AFL prior to the merger announcement, but quickly realized the AFL was probably his only viable path back into NFL after the older league awarded its sixteenth franchise to New Orleans. Also, Cincinnati was not going to have a 50,000-seat stadium ready (Riverfront Stadium) until 1970. Brown paid $10 million for his franchise (400 times the 1960 franchise fee of $25,000), famously stating "I didn't pay ten million dollars to be in the AFL."


title: AFL–NFL merger

text: As 1970 approached, three NFL teams (the Baltimore Colts, Cleveland Browns, and Pittsburgh Steelers), agreed to join the ten AFL teams (the Cincinnati Bengals and Miami Dolphins had joined the original Boston Patriots, Buffalo Bills, Denver Broncos, Houston Oilers, Kansas City Chiefs, New York Jets, Oakland Raiders, and San Diego Chargers) to form the American Football Conference (AFC). The other thirteen NFL teams (Atlanta Falcons, Chicago Bears, Dallas Cowboys, Detroit Lions, Green Bay Packers, Los Angeles Rams, Minnesota Vikings, New Orleans Saints, New York Giants, Philadelphia Eagles, St. Louis Cardinals, San Francisco 49ers and Washington Redskins) became part of the National Football Conference (NFC).


title: AFL–NFL merger

text: Since 1970, the Super Bowl has featured the champions of the AFC and NFC. Both are determined each season by the league's playoff tournament. With the creation of the new conferences of equal size, it was deemed necessary that they each be aligned into three divisions of four or five teams each. Prior to 1970, both leagues experimented with new playoff formats in place of the traditional format where the division champions faced each other in a single championship game, and where one-game playoffs were played to settle ties for the division crown. With the addition of a sixteenth team in 1967 the NFL expanded to four divisions, and also replaced the possibility of tiebreaker games with an elaborate set of performance-based tiebreakers to determine division champions. The AFL waited until its last season to eliminate the possibility of tiebreaker games when it granted the division runners up playoff berths and implemented the NFL tiebreaking formula.


title: AFL–NFL merger

text: Both playoff formats proved controversial. The 1967 Baltimore Colts tied the Los Angeles Rams for the best record in the NFL at 11-1-2, but because they lost the tiebreaker to the Rams they missed the playoffs altogether as opposed to playing a tiebreaker game as would have occurred in the previous season. In the AFL's final year, the 1969 Houston Oilers claimed a playoff berth despite a mediocre 6-6-2 record - no .500 team had ever qualified for the playoffs in a professional American football league before. To minimize the chance of any recurrence of such controversies, the 1970 playoff format combined elements of both leagues' formats. Four teams would qualify for the postseason from each conference (same as in 1969), thus only the ""Best" Second Place Team" (as it was originally called) would reach the postseason. Fans and media quickly dubbed this team the "wild card" and the NFL soon made that name official. The playoff format has changed several times since 1970 particularly as additional wild card teams and divisions have been added, but it has always been identical in each conference.


title: AFL–NFL merger

text: Although the AFC teams quickly decided on a divisional alignment along mostly geographic lines, the 13 NFC owners had trouble deciding which teams would play in which divisions. Many NFC teams were attempting to avoid placement in a division with the Cowboys and/or the Vikings, and were trying to angle their way into the same division as the Saints, the weakest team in professional football at the time. The 49ers and Rams, both in California, were guaranteed to be in the same division as the only NFC teams west of the Rocky Mountains. One early proposal would have put the two California teams together with the three Northeast teams—the New York Giants, Philadelphia Eagles and Washington Redskins—reminiscent of the Western Conference's Coastal Division which had put L.A. and S.F. together with Baltimore and Atlanta from 1967 to 1969. The final five proposals were as follows:


title: AFL–NFL merger

text: These five combinations were written up on slips of paper, sealed into envelopes and put into a fish bowl (other sources say a flower vase), and the official NFC alignment—Plan 3—was pulled out by Rozelle's secretary, Thelma Elkjer. Of the five plans considered, the one that was put into effect was the only one which had Minnesota remaining in the Central Division and Dallas playing in the Eastern Division. This preserved the Vikings' place with geographical rivals Chicago, Detroit, and Green Bay, and the Cowboys' rivalries with the Redskins, Eagles and Giants. It also was the only one of the final five proposals in which there were no warm weather cities in the Central Division. More controversially, the new alignment put both of the two newest NFC franchises, the Saints and Falcons from the Deep South, with the 49ers and Rams. The Falcons had already been playing the California teams in the NFL Coastal Division, but the Saints were in the NFL Capitol Division (with Dallas, Washington, Philadelphia) of the Eastern Conference and now faced two trips to the West Coast per season. The Rams were expected to dominate the West, but the 49ers won the division in its first three seasons before the Rams won the next seven titles (the Falcons did not win the division until 1980, and the Saints not until 1991).


title: AFL–NFL merger

text: Meanwhile, all three of the major television networks signed contracts to televise games, thus ensuring the combined league's stability. CBS agreed to broadcast all games where an NFC team was on the road, NBC agreed to broadcast all games where an AFC team was on the road, and ABC agreed to broadcast "Monday Night Football", making the NFL the first league to have a regular series of national telecasts in prime time.


title: AFL–NFL merger

text: Many observers believe that the NFL got the better end of the bargain, as Oakland Raiders owner Al Davis and New York Jets owner Sonny Werblin resisted the indemnity payments.


title: AFL–NFL merger

text: Long-time sports writer Jerry Magee of the "San Diego Union-Tribune" wrote: "Al Davis taking over as commissioner was the strongest thing the AFL ever did. He thought the AFL–NFL merger was a detriment to the AFL." However, other observers consider those scenarios far-fetched: the NFL had a richer television contract at the time of the merger, in large part because of market exclusivity in such leading population centers as Los Angeles, Chicago, Detroit, Philadelphia, Washington, Baltimore, and Atlanta and Dallas–Fort Worth, which were rapidly increasing in population and would emerge as media strongholds in the 1970s.


title: AFL–NFL merger

text: On the other hand, the AFL had teams in cities that were not among the nation's leading media markets, such as Miami (the only major professional sports franchise in Florida until the addition of the Buccaneers in 1976), Buffalo, and Denver (all of which at the time had no other major league teams), and Kansas City (which at the time had only a failing baseball team that was ultimately relocated). Other than the shared New York and Bay Area markets, the AFL's largest market was Houston, where the Oilers had little following outside southeast Texas due to the Cowboys' emergence. Most American Football League fans wanted to see an annual interleague championship with the NFL, but many neither expected nor favored a full merger and were thus left disappointed because they wanted their league to continue. Those feelings were reinforced when American Football League teams won the final two AFL–NFL World Championship games after the 1968 and 1969 seasons.


title: AFL–NFL merger

text: Nevertheless, despite the AFL triumphs in Super Bowls III and IV, the old-guard NFL was still widely expected to dominate the merged league over the course of an entire season. In 1970, these predictions were proven to be more or less correct: out of 60 regular season games pitting old-line NFL teams versus former AFL teams, former AFL teams went 19–39 (two games, Buffalo at Baltimore in week 9 and St. Louis at Kansas City in week 10, ended in ties). Only Oakland managed to post a winning record against old-line NFL opposition, going 3–2 (defeating Washington, Pittsburgh and Cleveland; losing to Detroit and San Francisco) before losing to the Colts in the AFC championship. Nevertheless, out of the three NFL teams to join the AFC, only the Colts managed to secure a playoff berth. The Browns and Steelers both missed out due to a stunning second-half performance by the Cincinnati Bengals, who overcame a 1–6 start and their two old-guard division rivals to secure the first-ever NFL playoff berth for a third year expansion team. Ultimately however, it was the Colts who were triumphant—they defeated both the Bengals and Raiders to become the first team to represent the AFC in a post-merger Super Bowl, where they defeated the Dallas Cowboys 16–13 to win Super Bowl V, the franchise's last NFL championship in Baltimore and last overall until 2006.


title: AFL–NFL merger

text: Even the undefeated Miami Dolphins were slight underdogs to the old-guard Washington Redskins in Super Bowl VII, but Miami won 14–7 to cap the only perfect championship season in NFL history. Not until Super Bowl VIII in 1974 was a former AFL team favored to win the Vince Lombardi Trophy, with the Dolphins trouncing the Minnesota Vikings 24–7 to repeat as champions; the Dolphins were also the first former AFL team to win a Super Bowl championship (and represent the AFC) after the merger. It took until Super Bowl XI in 1977 for an original AFL team to win a post-merger NFL championship, when the Oakland Raiders did so.


title: AFL–NFL merger

text: Each of the first 29 games on Monday Night Football featured at least one team from the old-guard NFL, with the first nationally televised prime time game between two former AFL teams being Oakland at Houston on October 9, 1972.


title: AFL–NFL merger

text: Eventually, the AFC teams caught and passed the NFC during the mid- to late-1970s. But even then, NFL proponents claimed that the three NFL teams that joined the AFL to form the AFC were largely the reason. Altogether, these teams played in each of the first three AFC Championship Games, and in eight of the first ten games (out of which they won five).


title: AFL–NFL merger

text: However, while the Colts and Browns were respectable playoff contenders during this period, it was the Steelers who dominated the league, winning four Super Bowls in six years in 1974–1979. From the perspective of AFL proponents, this was "not" a continuation of "old NFL" dominance. Before the merger, the Steelers had been perennially close to or in last place in the NFL since their foundation in 1933, including a 1–13 record in 1969 (tied with the Chicago Bears for the worst record in the NFL), with only eight winning seasons and just one playoff appearance (in 1947, where they were shut out) in that time.


title: AFL–NFL merger

text: The $3 million relocation fee that the Steelers received for joining the AFC after the merger, along with a new stadium and winning a coin-flip tiebreaker against the Bears for the number-one pick in the 1970 NFL draft (which ended up being future Hall of Fame quarterback Terry Bradshaw) helped them rebuild into a team that could compete with the other "old NFL" teams.


title: AFL–NFL merger

text: The merger paved the way for a new era of prosperity for the NFL. While a number of rival major professional football leagues have commenced play since 1970 including the XFL, WFL, USFL and UFL, and while the CFL once experimented with U.S.-based teams, none of these ventures came close to being a serious challenge to the NFL. The aforementioned U.S. leagues folded outright after one, two, three and four seasons respectively, while the CFL reverted to being an all-Canadian league after three seasons.


title: AFL–NFL merger

text: While the Buccaneers joined the AFC in 1976, the Seahawks joined the NFC. The 1976 expansion teams switched conference before their second season in the league, becoming the first NFL teams to change conferences after the merger; the Seahawks returned to the NFC in 2002 upon the league's realignment that year.


title: AFL–NFL merger

text: Four more NFL teams that were not specified in the merger agreement would be established between 1995 and 2002:


title: AFL–NFL merger

text: In total, out of the first 47 AFC Championship Games, sixteen have featured two former AFL teams and 45 have featured at least one former AFL team—the only exceptions being the 1995 championship game between the Steelers and Colts, and the 2008 game between the Steelers and Ravens. Out of the first 46 post-merger Super Bowls, former AFL teams have won 12, lost 21 and did not qualify for the remaining 13. The latter 13 games have all involved one of the three "old guard" organizations that joined the AFC in 1970, with the Steelers playing in eight, the Colts in three (one representing Baltimore and two representing Indianapolis) and the Ravens in two.


title: AFL–NFL merger

text: Somewhat ironically, the two AFL teams that won Super Bowls prior to the merger (the Jets and Chiefs) were also the last two former AFL teams that had never played in a post-merger championship game. (The Chiefs broke that streak in 2020, when they appeared in Super Bowl LIV.) Four extant NFL teams have yet to reach the Super Bowl at all, including two pre-merger NFL franchises (the Browns and Lions) and two post-merger expansion teams (the Jaguars and Texans). The Houston Oilers never reached a post-merger championship game prior to relocating to Tennessee, thus making Houston the only AFL city that has yet to send a team to the Super Bowl.


title: AFL–NFL merger

text: In spite of Rozelle's promise that there would be no re-locations involving teams in existence at the time of the merger, by the end of his tenure as commissioner in 1989 three franchises had moved to a different market from where they were based in 1970 (although the league did take legal action in an unsuccessful attempt to prevent the first such move, that of the Raiders, from taking place).


title: AFL–NFL merger

text: As of 2021, six NFL franchises (the Raiders, Colts, Cardinals, Rams, Oilers/Titans and Chargers) have been involved in post-merger re-locations while an additional franchise (the Browns) temporarily suspended operations as an alternative to re-location. Of the six teams that have re-located since the merger, two (the Raiders and Rams) have returned to the cities they played in at the time of the merger, while the other teams only moved once. However, the Chargers, who had moved to San Diego in 1961 before the merger, returned to Los Angeles in 2017, making them the only team to go through a relocation as a member of both leagues. Also, the Raiders moved a third time, leaving Oakland once more, this time for Las Vegas in 2020.


title: AFL–NFL merger

text: The Rams' return from St. Louis to Los Angeles ended an interval lasting 21 years in which there was no NFL team in Los Angeles—the longest such period involving any NFL city of the post-merger era—and resulted in St. Louis replacing Los Angeles as the only 1969 NFL city without a current NFL team. The NFL has not simultaneously fielded teams in all sixteen of its 1969 markets since the Colts relocated to Indianapolis after the 1983 season. It had fielded teams in all ten 1969 AFL cities from the 2002 season (when the Texans joined the league) until the conclusion of the 2016 season (when the Chargers returned to Los Angeles, leaving San Diego without an NFL team).


title: AFL–NFL merger

text: Neither Portland nor Memphis (the cities that were due to receive AFL franchises via relocation in the rejected 1964 merger proposal) have received an NFL franchise as of 2021. Memphis in particular has made repeated bids for an NFL team (including the Memphis Hound Dogs and the Memphis Grizzlies court case), but all have failed. Memphis would later serve as a temporary home to the Tennessee Oilers for the 1997 season following their departure from Houston. The agreement was originally slated to last for two seasons, but lackluster fan support in Memphis caused the arrangement to be cut short.


title: AFL–NFL merger

text: A league rule passed as a result of the merger required all NFL teams to use stadiums that seated over 50,000 spectators. At the time, several teams had stadiums that were not up to that standard (see above). Most either built a new stadium by 1971 or, in the case of Chicago, moved to an existing stadium in the metro area that met the requirement. The Buffalo Bills situation would prove to be a pattern for later teams; Buffalo interests were very slow to come to an agreement on a new stadium, and it was only after Bills owner Ralph Wilson began arranging for a move to Seattle (a tactic that would later be used by many other teams in their quests for new stadiums in their hometowns, later using cities such as Los Angeles and San Antonio) that Western New York finally agreed to build Rich Stadium, which opened in 1973.


title: AFL–NFL merger

text: The Super Bowl has been used as an incentive by the league to convince local governments, businesses, and voters to support the construction, seat licenses and taxes associated with new or renovated stadiums. Therefore, the league has and continues to award Super Bowls to cities that have built new football stadiums for their existing franchises, though all outdoor Super Bowls continued to be played in warmer climates, with the exception of Super Bowl XLVIII played in the new Meadowlands stadium.


title: AFL–NFL merger

text: Only eight Super Bowls since 1983 have been played in stadiums used by three of these expansion teams: five in Tampa (two at Tampa Stadium and three at Raymond James Stadium), one in Jacksonville and two in Houston.


title: AFL–NFL merger

text: In some cases, cities have been selected as provisional Super Bowl sites, with the construction or renovation of a suitable facility as a major requirement for hosting the actual game. In the past, New York City and San Francisco have each received provisional site awards. In both cities, the league moved the game to a different site when public funding initiatives failed. The most recent provisional site award went to Kansas City for a Super Bowl to be played in 2015 in Arrowhead Stadium, but Kansas City withdrew their request because the funding for the new roof failed in an April 2006 referendum.


title: AFL–NFL merger

text: The Kansas City Chiefs, Cleveland Browns, Cincinnati Bengals, Denver Broncos, Houston Texans, Pittsburgh Steelers, Philadelphia Eagles, Chicago Bears, Tampa Bay Buccaneers, Seattle Seahawks, Detroit Lions, Arizona Cardinals, Indianapolis Colts and Minnesota Vikings are all teams who have received a significant amount of public financing to either construct or upgrade the stadiums in which they currently play.


title: AFL–NFL merger

text: The state of Louisiana has been making cash payouts to the New Orleans Saints since 2001 in order to keep the team from moving. The state received over $185 million from the Federal Emergency Management Agency and other sources to repair and renovate the Superdome following damage from Hurricane Katrina in 2005. Louisiana then began a five-year, $320 million renovation project for the stadium in 2006; another $450 million renovation began in 2020 to upgrade the facility for Super Bowl LIX in February 2025.


title: AFL–NFL merger

text: In addition, St. Louis and Baltimore also publicly financed stadiums for the purpose of luring the former Los Angeles Rams and the first incarnation of the Cleveland Browns. The Rams returned to Los Angeles in 2016 following the 2015 season and moved into a new stadium in Inglewood, California in 2020 alongside the Chargers who also relocated to the city from San Diego in 2017. The Raiders would move from Oakland once more, this time to Las Vegas with a new stadium built there in 2020.


title: AFL–NFL merger

text: Entrepreneurs interested in other sports in North America would follow the AFL's example in competing with the established "major" leagues.


title: Tom Malinowski

text: Tomasz "Tom" P. Malinowski (; born September 23, 1965) is an American politician and diplomat who is the U.S. representative from New Jersey's 7th congressional district. A Democrat, he served as Assistant Secretary of State for Democracy, Human Rights, and Labor in the Obama administration.


title: Tom Malinowski

text: A vocal opponent of Donald Trump, Malinowski was first elected in 2018, defeating Republican incumbent Leonard Lance by five points. He was reelected in 2020 by a narrower margin against New Jersey State Senate's Minority Leader, Thomas Kean Jr. In a 2022 rematch, Kean defeated Malinowski.


title: Tom Malinowski

text: Malinowski was born in Słupsk, Poland, and lived in Brwinów until leaving the country at the age of six with his mother, Joanna, who married Blair Clark. He was raised in Princeton, New Jersey, and graduated from Princeton High School in 1983, where he wrote for the school newspaper "The Tower" and was an intern in Senator Bill Bradley's office. Malinowski received a Bachelor of Arts in political science from the University of California, Berkeley, in 1987 and a Master of Philosophy from St Antony's College, Oxford, in 1991, where he was a Rhodes Scholar.


title: Tom Malinowski

text: Malinowski worked as a special assistant to Senator Daniel Patrick Moynihan in 1988. He worked for the Institute for Human Sciences in Vienna, Austria, and later as a research assistant for the Ford Foundation in 1993. From 1994 to 1998, Malinowski was a speechwriter for Secretaries of State Warren Christopher and Madeleine Albright as well as a member of the Policy Planning Staff at the Department of State. From 1998 to 2001, Malinowski served as senior director on the National Security Council at the White House.


title: Tom Malinowski

text: From 2001 to 2013, Malinowski was the Washington director for Human Rights Watch. In this position, he advocated for the end of torture techniques and black sites used by the U.S. government during the War on Terror. He campaigned for democratic reforms in Myanmar and financial sanctions on its leadership. Malinowski argued for the recognition of women's rights as a precondition to any peace talks with the Taliban. He also pushed for a no-fly zone in Syria during the ongoing civil war. Malinowski opposed supplying Israel with cluster munitions because of their misuse in Lebanon and asked then-Senator Hillary Clinton to not support Israel's construction of a wall in the occupied West Bank.


title: Tom Malinowski

text: Some saw Malinowski as a likely nominee for Assistant Secretary of State for Democracy, Human Rights, and Labor, but his previous registration as a lobbyist while at Human Rights Watch necessitated a waiver from the President. On July 8, 2013, during Obama's second term, Malinowski was nominated to serve as Assistant Secretary of State for Democracy, Human Rights, and Labor. He testified before the Senate Foreign Relations Committee on September 24, 2013, and was confirmed by the U.S. Senate on April 2, 2014. According to columnist Jennifer Rubin, leaders from both parties praised Malinowski in 2014 for his defense of human rights and his work toward ending torture.


title: Tom Malinowski

text: In 2016, Malinowski said the State Department planned to release a list of North Korean human rights abusers. He backed the United Nations' efforts to investigate possible war crimes committed during the Sri Lankan Civil War. He assisted with sanctioning Russian officials under the Magnitsky Act for human rights abuses.


title: Tom Malinowski

text: In July 2014, Bahrain's government expelled Malinowski after he met with members of a Bahraini opposition group during a scheduled visit. The foreign ministry of Bahrain asserted that his meeting was an improper intervention in the country's affairs but said the incident would not affect Bahrain–U.S. relations. The U.S. State Department released a statement of concern about the actions while Secretary of State John Kerry called Bahrain's actions unacceptable and contrary to diplomatic protocol. Malinowski returned to Bahrain in December 2014 with the Assistant Secretary of State for Near Eastern Affairs.


title: Tom Malinowski

text: Following the end of his tenure at the State Department, Malinowski joined fellow former Obama officials to lobby Congress to prevent the Trump administration from lifting the sanctions on Russia following its annexation of Crimea. He criticized Donald Trump for having an "obscene fondness" for the world's tyrants and for instituting a "complete departure from decades of American tradition."


title: Tom Malinowski

text: On October 2, 2017, Malinowski announced his candidacy for New Jersey's 7th congressional district in the 2018 midterm elections. He decided to run for Congress after the 2016 election of Donald Trump, which he saw as an indication that America was in "deep trouble". Malinowski cited health care, immigration, diplomacy, environmental policy, and infrastructure as areas of focus.


title: Tom Malinowski

text: Malinowski supports the Affordable Care Act and criticized the Republican Party's attempts to dismantle it. He supports a public health insurance option, but opposes Medicare for all. He supports raising the minimum wage to $15 per hour as well as stronger collective bargaining rights and protections for workers.


title: Tom Malinowski

text: In the June 5 Democratic primary election, Malinowski defeated social worker Peter Jacob and lawyer Goutam Jois with 66.8% of the vote, winning all counties in the district.


title: Tom Malinowski

text: Malinowski won the November 6 general election with 51.7% of the vote. He and Lance each carried three of the district's six counties; Malinowski won Essex, Somerset and Union, while Lance carried Morris, Warren and his native Hunterdon. But Malinowski won the district's shares of Somerset and Union counties, the two most populous counties in the district, by 22,300 votes, which exceeded the overall margin of 16,200 votes.


title: Tom Malinowski

text: During his reelection campaign, Malinowski faced death threats after introducing a bill condemning the conspiratorial group QAnon. The National Republican Congressional Committee then aired ads falsely accusing him of lobbying to protect sexual predators when he worked for Human Rights Watch.


title: Tom Malinowski

text: Malinowski was reelected, defeating New Jersey Senate Republican leader Tom Kean Jr. by 1.2%. Due to the very close margin, the election remained unresolved for weeks. In terms of both absolute numbers and vote percentage, Malinowski's race was the closest House race in the country to be won by a Democrat.


title: Tom Malinowski

text: Malinowski unsuccessfully ran for reelection in the district for the 2022 elections in a rematch against Tom Kean Jr.


title: Tom Malinowski

text: When he took office in January 2019, Malinowski became the first Democrat to represent the 7th since 1956.


title: Tom Malinowski

text: Malinowski was the first member of the New Jersey House delegation to call to begin the impeachment inquiry against Trump in May 2019. He endorsed Democratic presidential nominee Joe Biden in January 2020.


title: Tom Malinowski

text: During his first term, Malinowski advocated for efforts to prohibit weapons sales to Saudi Arabia for use in the Yemen conflict. He also advocated for accountability related to Saudi Arabia’s role in the murder of Jamal Khashoggi. His work contributed to the release of the Khashoggi Report and the subsequent Khashoggi ban.


title: Tom Malinowski

text: American video game company Activision Blizzard punished a Hong Kong-based professional gamer for supporting pro-democracy Hong Kong protests. Malinowski accused Blizzard and Apple of censorship. He co-signed a letter to Activision Blizzard CEO Bobby Kotick that read, "As China amplifies its campaign of intimidation, you and your company must decide whether to look beyond the bottom line and promote American values—like freedom of speech and thought—or to give in to Beijing’s demands in order to preserve market access."


title: Tom Malinowski

text: The America COMPETES Act legislation, passed by the House in February 2022, included provisions Malinowski wrote. He was subsequently appointed to the conference committee that finalized the bill.


title: Tom Malinowski

text: In April 2021, the Associated Press reported that Malinowski had traded approximately $1 million of stock in medical and tech companies involved in the COVID-19 pandemic response. Malinowski failed to disclose the trades within the period of time required by federal law; he said the failure to disclose the trades was an error. Two complaints were filed against him with the Office of Congressional Ethics, which announced in October 2021 that it found "substantial reason to believe" that Malinowski had violated federal laws designed to defend against conflicts of interest. The Office of Congressional Ethics formally referred its Malinowski investigation to the House Committee on Ethics, which continued its own investigation. The House Ethics Committee's investigation into Malinowski's stock trading is ongoing.


title: Tom Malinowski

text: Malinowski moved to Rocky Hill, New Jersey, close to where he grew up, in September 2017. In 2020, he moved to the Ringoes section of East Amwell Township, New Jersey.


title: Tom Malinowski

text: Malinowski's stepfather Blair Clark was a journalist. Clark's sister was Anne Martindell, a member of the New Jersey State Senate (1974–1977) and a United States ambassador to New Zealand (1979–1981).


title: Mark Neveldine

text: Mark Neveldine (born May 11, 1973) is an American filmmaker. He is best known for frequently collaborating with Brian Taylor as Neveldine/Taylor.


title: Mark Neveldine

text: Neveldine was born in Watertown, New York, to Tom Neveldine and Carolyn Dowd Fitzpatrick. He attended college at Hobart and William Smith Colleges, where he studied drama and psychology.


title: Mark Neveldine

text: After graduating, he moved to Manhattan, where he began his career as an actor, writer, and director of nearly thirty productions. He subsequently transitioned into film work, becoming a cinematographer on music videos, documentaries and a television pilot.


title: Mark Neveldine

text: Neveldine directed "", the sequel to the Marvel Comics' superhero film "Ghost Rider", alongside partner Brian Taylor.


title: Mark Neveldine

text: Neveldine married actress Alison Lohman in Watertown, New York on August 19, 2009, at St. Anthony's Catholic Church. They have three children together.


title: This was their finest hour

text: "This was their finest hour" was a speech delivered by Winston Churchill to the House of Commons of the United Kingdom on 18 June 1940, just over a month after he took over as Prime Minister at the head of an all-party coalition government.


title: This was their finest hour

text: It was the third of three speeches which he gave during the period of the Battle of France, after the "Blood, toil, tears and sweat" speech of 13 May and the "We shall fight on the beaches" speech of 4 June. "This was their finest hour" was made after France had sought an armistice on the evening of 16 June.


title: This was their finest hour

text: In his speech, Churchill justified the low level of support it had been possible to give to France since the Dunkirk evacuation, and reported the successful evacuation of most of the supporting forces. He resisted pressure to purge the coalition of appeasers, or otherwise indulge in recrimination. He reviewed the forces still available to prevent or repel any attempted invasion, summing up the review as follows:


title: This was their finest hour

text: I have thought it right upon this occasion to give the House and the country some indication of the solid, practical grounds upon which we base our inflexible resolve to continue the war, and I can assure them that our professional advisers of the three Services unitedly advise that we should do so, and that there are good and reasonable hopes of final victory.


title: This was their finest hour

text: He reported messages of support from the Dominions and justified confidence in victory, even if it was not yet clear how that victory could be achieved.


title: This was their finest hour

text: In casting up this dread balance-sheet, contemplating our dangers with a disillusioned eye, I see great reason for intense vigilance and exertion, but none whatever for panic or despair. During the first four years of the last war the Allies experienced...nothing but disaster and disappointment, and yet at the end their morale was higher than that of the Germans, who had moved from one aggressive triumph to another. During that war we repeatedly asked ourselves the question, "How are we going to win?" and no one was able ever to answer it with much precision, until at the end, quite suddenly, quite unexpectedly, our terrible foe collapsed before us.


title: This was their finest hour

text: The peroration, even at a moment of great apparent danger to British national survival, talks not only of national survival and national interest but also of noble causes (freedom, Christian civilisation and the rights of small nations) for which Britain was fighting and for which Churchill thought the United States should and eventually would fight. "The War Illustrated" published the speech with the title "'If the Empire lasts a thousand years men will say, this was their finest hour'".


title: This was their finest hour

text: The speech was delivered to the Commons at 3:49 pm, and lasted 36 minutes. Churchill, as was his habit, made revisions to his 23-page typescript right up to and during the speech. The final passage of his typescript was laid out in blank verse format, which Churchill scholars consider reflective of the influence of the Psalms on his oratory style.


title: T-symmetry

text: T-symmetry or time reversal symmetry is the theoretical symmetry of physical laws under the transformation of time reversal,


title: T-symmetry

text: Since the second law of thermodynamics states that entropy increases as time flows toward the future, in general, the macroscopic universe does not show symmetry under time reversal. In other words, time is said to be non-symmetric, or asymmetric, except for special equilibrium states when the second law of thermodynamics predicts the time symmetry to hold. However, quantum noninvasive measurements are predicted to violate time symmetry even in equilibrium, contrary to their classical counterparts, although this has not yet been experimentally confirmed.


title: T-symmetry

text: Daily experience shows that T-symmetry does not hold for the behavior of bulk materials. Of these macroscopic laws, most notable is the second law of thermodynamics. Many other phenomena, such as the relative motion of bodies with friction, or viscous motion of fluids, reduce to this, because the underlying mechanism is the dissipation of usable energy (for example, kinetic energy) into heat.


title: T-symmetry

text: The question of whether this time-asymmetric dissipation is really inevitable has been considered by many physicists, often in the context of Maxwell's demon. The name comes from a thought experiment described by James Clerk Maxwell in which a microscopic demon guards a gate between two halves of a room. It only lets slow molecules into one half, only fast ones into the other. By eventually making one side of the room cooler than before and the other hotter, it seems to reduce the entropy of the room, and reverse the arrow of time. Many analyses have been made of this; all show that when the entropy of room and demon are taken together, this total entropy does increase. Modern analyses of this problem have taken into account Claude E. Shannon's relation between entropy and information. Many interesting results in modern computing are closely related to this problem — reversible computing, quantum computing and physical limits to computing, are examples. These seemingly metaphysical questions are today, in these ways, slowly being converted into hypotheses of the physical sciences.


title: T-symmetry

text: The current consensus hinges upon the Boltzmann–Shannon identification of the logarithm of phase space volume with the negative of Shannon information, and hence to entropy. In this notion, a fixed initial state of a macroscopic system corresponds to relatively low entropy because the coordinates of the molecules of the body are constrained. As the system evolves in the presence of dissipation, the molecular coordinates can move into larger volumes of phase space, becoming more uncertain, and thus leading to increase in entropy.


title: T-symmetry

text: One resolution to irreversibility is to say that the constant increase of entropy we observe happens "only" because of the initial state of our universe. Other possible states of the universe (for example, a universe at heat death equilibrium) would actually result in no increase of entropy. In this view, the apparent T-asymmetry of our universe is a problem in cosmology: why did the universe start with a low entropy? This view, supported by cosmological observation (such as the isotropy of the Cosmic Microwave Background) connect this problem to the question of "initial conditions" of the universe.


title: T-symmetry

text: The laws of gravity seem to be time reversal invariant in classical mechanics; however, specific solutions need not be.


title: T-symmetry

text: An object can cross through the event horizon of a black hole from the outside, and then fall rapidly to the central region where our understanding of physics breaks down. Since within a black hole the forward light-cone is directed towards the center and the backward light-cone is directed outward, it is not even possible to define time-reversal in the usual manner. The only way anything can escape from a black hole is as Hawking radiation.


title: T-symmetry

text: The time reversal of a black hole would be a hypothetical object known as a white hole. From the outside they appear similar. While a black hole has a beginning and is inescapable, a white hole has an ending and cannot be entered. The forward light-cones of a white hole are directed outward; and its backward light-cones are directed towards the center.


title: T-symmetry

text: The event horizon of a black hole may be thought of as a surface moving outward at the local speed of light and is just on the edge between escaping and falling back. The event horizon of a white hole is a surface moving inward at the local speed of light and is just on the edge between being swept outward and succeeding in reaching the center. They are two different kinds of horizons—the horizon of a white hole is like the horizon of a black hole turned inside-out.


title: T-symmetry

text: The modern view of black hole irreversibility is to relate it to the second law of thermodynamics, since black holes are viewed as thermodynamic objects. For example, according to the gauge–gravity duality conjecture, all microscopic processes in a black hole are reversible, and only the collective behavior is irreversible, as in any other macroscopic, thermal system.


title: T-symmetry

text: In physical and chemical kinetics, T-symmetry of the mechanical microscopic equations implies two important laws: the principle of detailed balance and the Onsager reciprocal relations. T-symmetry of the microscopic description together with its kinetic consequences are called microscopic reversibility.


title: T-symmetry

text: Let us consider the example of a system of charged particles subject to a constant external magnetic field: in this case the canonical time reversal operation that reverses the velocities and the time formula_12 and keeps the coordinates untouched is no more a symmetry for the system. Under this consideration, it seems that only Onsager–Casimir reciprocal relations could hold; these equalities relate two different systems, one subject to formula_17 and another to formula_25, and so their utility is limited. However, there was proved that it is possible to find other time reversal operations which preserve the dynamics and so Onsager reciprocal relations; in conclusion, one cannot state that the presence of a magnetic field always breaks T-symmetry.


title: T-symmetry

text: Most systems are asymmetric under time reversal, but there may be phenomena with symmetry. In classical mechanics, a velocity "v" reverses under the operation of "T", but an acceleration does not. Therefore, one models dissipative phenomena through terms that are odd in "v". However, delicate experiments in which known sources of dissipation are removed reveal that the laws of mechanics are time reversal invariant. Dissipation itself is originated in the second law of thermodynamics.


title: T-symmetry

text: The motion of a charged body in a magnetic field, "B" involves the velocity through the Lorentz force term "v"×"B", and might seem at first to be asymmetric under "T". A closer look assures us that "B" also changes sign under time reversal. This happens because a magnetic field is produced by an electric current, "J", which reverses sign under "T". Thus, the motion of classical charged particles in electromagnetic fields is also time reversal invariant. (Despite this, it is still useful to consider the time-reversal non-invariance in a "local" sense when the external field is held fixed, as when the magneto-optic effect is analyzed. This allows one to analyze the conditions under which optical phenomena that locally break time-reversal, such as Faraday isolators and directional dichroism, can occur.)


title: T-symmetry

text: In physics one separates the laws of motion, called kinematics, from the laws of force, called dynamics. Following the classical kinematics of Newton's laws of motion, the kinematics of quantum mechanics is built in such a way that it presupposes nothing about the time reversal symmetry of the dynamics. In other words, if the dynamics are invariant, then the kinematics will allow it to remain invariant; if the dynamics is not, then the kinematics will also show this. The structure of the quantum laws of motion are richer, and we examine these next.


title: T-symmetry

text: This section contains a discussion of the three most important properties of time reversal in quantum mechanics; chiefly,


title: T-symmetry

text: The strangeness of this result is clear if one compares it with parity. If parity transforms a pair of quantum states into each other, then the sum and difference of these two basis states are states of good parity. Time reversal does not behave like this. It seems to violate the theorem that all abelian groups be represented by one-dimensional irreducible representations. The reason it does this is that it is represented by an anti-unitary operator. It thus opens the way to spinors in quantum mechanics.


title: T-symmetry

text: On the other hand, the notion of quantum-mechanical time reversal turns out to be a useful tool for the development of physically motivated quantum computing and simulation settings, providing, at the same time, relatively simple tools to assess their complexity. For instance, quantum-mechanical time reversal was used to develop novel boson sampling schemes and to prove the duality between two fundamental optical operations, beam splitter and squeezing transformations.


title: T-symmetry

text: In formal mathematical presentations of T-symmetry, three different kinds of notation for T need to be carefully distinguished: the T that is an involution, capturing the actual reversal of the time coordinate, the T that is an ordinary finite dimensional matrix, acting on spinors and vectors, and the T that is an operator on a infinite-dimensional Hilbert space.


title: T-symmetry

text: For a real (not complex) classical (unquantized) scalar field formula_26, the time reversal involution can simply be written as


title: T-symmetry

text: as time reversal leaves the scalar value at a fixed spacetime point unchanged, up to an overall sign formula_28. A slightly more formal way to write this is


title: T-symmetry

text: which has the advantage of emphasizing that formula_30 is a map, and thus the "mapsto" notation formula_31 whereas formula_32 is a factual statement relating the old and new fields to one-another.


title: T-symmetry

text: Unlike scalar fields, spinor and vector fields formula_33 might have a non-trivial behavior under time reversal. In this case, one has to write


title: T-symmetry

text: where formula_35 is just an ordinary matrix. For complex fields, complex conjugation may be required, for which the mapping formula_36 can be thought of as a 2x2 matrix. For a Dirac spinor, formula_35 cannot be written as a 4x4 matrix, because, in fact, complex conjugation is indeed required; however, it can be written as an 8x8 matrix, acting on the 8 real components of a Dirac spinor.


title: T-symmetry

text: In the general setting, there is no "ab initio" value to be given for formula_35; its actual form depends on the specific equation or equations which are being examined. In general, one simply states that the equations must be time-reversal invariant, and then solves for the explicit value of formula_35 that achieves this goal. In some cases, generic arguments can be made. Thus, for example, for spinors in three-dimensional Euclidean space, or four-dimensional Minkowski space, an explicit transformation can be given. It is conventionally given as


title: T-symmetry

text: where formula_41 is the y-component of the angular momentum operator and formula_42 is complex conjugation, as before. This form follows whenever the spinor can be described with a linear differential equation that is first-order in the time derivative, which is generally the case in order for something to be validly called "a spinor".


title: T-symmetry

text: The formal notation now makes it clear how to extend time-reversal to an arbitrary tensor field formula_43 In this case,


title: T-symmetry

text: Covariant tensor indexes will transform as formula_45 and so on. For quantum fields, there is also a third T, written as formula_46 which is actually an infinite dimensional operator acting on a Hilbert space. It acts on quantized fields formula_47 as


title: T-symmetry

text: This can be thought of as a special case of a tensor with one covariant, and one contravariant index, and thus two formula_49's are required.


title: T-symmetry

text: All three of these symbols capture the idea of time-reversal; they differ with respect to the specific space that is being acted on: functions, vectors/spinors, or infinite-dimensional operators. The remainder of this article is not cautious to distinguish these three; the "T" that appears below is meant to be either formula_30 or formula_35 or formula_46 depending on context, left for the reader to infer.


title: T-symmetry

text: Eugene Wigner showed that a symmetry operation "S" of a Hamiltonian is represented, in quantum mechanics either by a unitary operator, , or an antiunitary one, where "U" is unitary, and "K" denotes complex conjugation. These are the only operations that act on Hilbert space so as to preserve the "length" of the projection of any one state-vector onto another state-vector.


title: T-symmetry

text: Consider the parity operator. Acting on the position, it reverses the directions of space, so that . Similarly, it reverses the direction of "momentum", so that , where "x" and "p" are the position and momentum operators. This preserves the canonical commutator , where "ħ" is the reduced Planck constant, only if "P" is chosen to be unitary, .


title: T-symmetry

text: On the other hand, the "time reversal" operator "T", it does nothing to the x-operator, , but it reverses the direction of p, so that . The canonical commutator is invariant only if "T" is chosen to be anti-unitary, i.e., .


title: T-symmetry

text: Another argument involves energy, the time-component of the four-momentum. If time reversal were implemented as a unitary operator, it would reverse the sign of the energy just as space-reversal reverses the sign of the momentum. This is not possible, because, unlike momentum, energy is always positive. Since energy in quantum mechanics is defined as the phase factor exp(–"iEt") that one gets when one moves forward in time, the way to reverse time while preserving the sign of the energy is to also reverse the sense of ""i"", so that the sense of phases is reversed.


title: T-symmetry

text: Similarly, any operation that reverses the sense of phase, which changes the sign of "i", will turn positive energies into negative energies unless it also changes the direction of time. So every antiunitary symmetry in a theory with positive energy must reverse the direction of time. Every antiunitary operator can be written as the product of the time reversal operator and a unitary operator that does not reverse time.


title: T-symmetry

text: This has an interesting consequence on the electric dipole moment (EDM) of any particle. The EDM is defined through the shift in the energy of a state when it is put in an external electric field: , where "d" is called the EDM and δ, the induced dipole moment. One important property of an EDM is that the energy shift due to it changes sign under a parity transformation. However, since d is a vector, its expectation value in a state |ψ⟩ must be proportional to ⟨ψ| "J" |ψ⟩, that is the expected spin. Thus, under time reversal, an invariant state must have vanishing EDM. In other words, a non-vanishing EDM signals both "P" and "T" symmetry-breaking.


title: T-symmetry

text: Some molecules, such as water, must have EDM irrespective of whether T is a symmetry. This is correct; if a quantum system has degenerate ground states that transform into each other under parity, then time reversal need not be broken to give EDM.


title: T-symmetry

text: Experimentally observed bounds on the electric dipole moment of the nucleon currently set stringent limits on the violation of time reversal symmetry in the strong interactions, and their modern theory: quantum chromodynamics. Then, using the CPT invariance of a relativistic quantum field theory, this puts strong bounds on strong CP violation.


title: T-symmetry

text: Experimental bounds on the electron electric dipole moment also place limits on theories of particle physics and their parameters.


title: T-symmetry

text: This means that the entries in Φ are ±1, as a result of which one may have either . This is specific to the anti-unitarity of "T". For a unitary operator, such as the parity, any phase is allowed.


title: T-symmetry

text: Next, take a Hamiltonian invariant under "T". Let |"a"⟩ and "T"|"a"⟩ be two quantum states of the same energy. Now, if , then one finds that the states are orthogonal: a result called Kramers' theorem. This implies that if , then there is a twofold degeneracy in the state. This result in non-relativistic quantum mechanics presages the spin statistics theorem of quantum field theory.


title: T-symmetry

text: Quantum states that give unitary representations of time reversal, i.e., have , are characterized by a multiplicative quantum number, sometimes called the T-parity.


title: T-symmetry

text: Particle physics codified the basic laws of dynamics into the standard model. This is formulated as a quantum field theory that has CPT symmetry, i.e., the laws are invariant under simultaneous operation of time reversal, parity and charge conjugation. However, time reversal itself is seen not to be a symmetry (this is usually called CP violation). There are two possible origins of this asymmetry, one through the mixing of different flavours of quarks in their weak decays, the second through a direct CP violation in strong interactions. The first is seen in experiments, the second is strongly constrained by the non-observation of the EDM of a neutron.


title: T-symmetry

text: Time reversal violation is unrelated to the second law of thermodynamics, because due to the conservation of the CPT symmetry, the effect of time reversal is to rename particles as antiparticles and "vice versa". Thus the second law of thermodynamics is thought to originate in the initial conditions in the universe.


title: T-symmetry

text: Strong measurements (both classical and quantum) are certainly disturbing, causing asymmetry due to the second law of thermodynamics. However,


title: T-symmetry

text: noninvasive measurements should not disturb the evolution, so they are expected to be time-symmetric. Surprisingly, it is true only in classical physics but not in quantum physics, even in a thermodynamically invariant equilibrium state. This type of asymmetry is independent of CPT symmetry but has not yet been confirmed experimentally due to extreme conditions of the checking proposal.


title: Steve Bisciotti

text: Stephen J. Bisciotti (; born April 10, 1960) is an American business executive and the current majority owner of the Baltimore Ravens of the NFL. He founded Aerotek, the largest privately owned staffing and recruiting company in the U.S. based in Hanover, Maryland, and cofounded Allegis Group, an international talent management firm headquartered in Hanover, Maryland that owns Aerotek; TEKsystems; Actalent; MarketSource; Major, Lindsey & Africa; Aston Carter; and Allegis Global Solutions.


title: Steve Bisciotti

text: Bisciotti was born on April 10, 1960 in Philadelphia, Pennsylvania, the youngest of three children in a middle class Italian-American family. In 1961, his parents, Bernard and Patricia Bisciotti, moved the family to Severna Park, Maryland, a suburb of Baltimore, for his father's job as a construction sales executive.


title: Steve Bisciotti

text: As a child, Bisciotti often went with his family to Baltimore Orioles and Colts games. When he was 8 years old, his father died of leukemia. After his father's death, his maternal grandfather, C. Gordon Johnston, a retired regional district salesman for Ford Motor Co., supported the family.


title: Steve Bisciotti

text: Bisciotti attended the Severn School but left after two years and transferred to Severna Park High School. In his senior year, he played on the football team, though he has said "I wasn’t much of a high school athlete, but played football, baseball, and basketball all the time when I was growing up".


title: Steve Bisciotti

text: In 1982, Bisciotti graduated from Salisbury State University in Maryland with a degree in liberal arts. A year later, at 23, he and his cousin Jim Davis started Aerotek, a staffing company in the aerospace and technology sectors. Running the company out of a basement office with secondhand equipment, Bisciotti and Davis produced $1.5 million in sales in the first year. Aerotek grew into the Allegis Group, which is now the largest privately held staffing firm in the world. Bisciotti's involvement in the sports business has brought more attention to his once low-profile company.


title: Steve Bisciotti

text: On March 27, 2000, NFL owners approved the sale of 49% of the Ravens to Bisciotti. In the deal, he had an option to purchase the remaining 51% for $325 million in 2004 from Art Modell. The Ravens won Super Bowl XXXV on January 28, 2001. On April 9, 2004 the NFL approved his purchase of the majority stake in the club.


title: Steve Bisciotti

text: One of the first projects Bisciotti directed as owner of the Ravens was to build the team's state-of-the-art training and practice facility, dubbed "The Castle," which opened in October 2004.


title: Steve Bisciotti

text: Bisciotti fired Brian Billick after the 2007 season, although Billick's eight years as the Ravens' head coach included the team's win in Super Bowl XXXV. He then surprised many observers by selecting John Harbaugh as his new coach, despite Harbaugh's peak of previous experience being a single year as a defensive backs coach after several successful years as the special teams coach for the Philadelphia Eagles.


title: Steve Bisciotti

text: In 2012, the Baltimore Ravens capitalized off a 10-6 season to go on to win Super Bowl XLVII against the San Francisco 49ers on February 3, 2013.


title: Steve Bisciotti

text: In 2009, Aerotek, the company Bisciotti co-founded, reached a $1.2 million settlement in a class-action lawsuit filed on behalf of more than 1,000 Aerotek workers who worked at a Verizon Internet Services call center in Martinsburg, West Virginia, which was closed in December 2006. The company then was sued to settle claims that the workers were not paid in a timely fashion for accrued personal time and were not paid all of the wages that were due in accordance with the West Virginia Wage Payment and Collection Act and Fair Labor Standards Act, according to Berkeley County Circuit Court records.


title: Steve Bisciotti

text: Bisciotti is Catholic and a board member for the Associated Catholic Charities and Mother Seton Academy. He and his wife Renee (Foote) Bisciotti have two sons. The family lives on the Point Field Landing of the Severn River in Maryland.


title: Steve Bisciotti

text: In addition to owning the Ravens, valued at $2.7 billion in 2019; Bisciotti also owns a $20 million yacht named “Winning Drive” and 2 Dassault Falcon private jets.


title: Denver metropolitan area

text: Denver is the central city of a conurbation region in the U.S. state of Colorado. The conurbation includes one continuous region consisting of the six central counties of Adams, Arapahoe, Broomfield, Denver, Douglas, and Jefferson. The Denver region is part of the Front Range Urban Corridor.


title: Denver metropolitan area

text: The United States Office of Management and Budget has delineated the Denver–Aurora–Lakewood, CO Metropolitan Statistical Area consisting of ten Colorado counties: the City and County of Denver, Arapahoe County, Jefferson County, Adams County, Douglas County, the City and County of Broomfield, Elbert County, Park County, Clear Creek County, and Gilpin County. The population, as of the 2020 Census, is 2,963,821, an increase of 16.5% since 2010.


title: Denver metropolitan area

text: The Office of Management and Budget also delineated the more extensive 12-county Denver–Aurora, CO Combined Statistical Area comprising the Denver-Aurora-Lakewood Metropolitan Statistical Area, the Boulder, CO Metropolitan Statistical Area, and the Greeley, CO Metropolitan Statistical Area.


title: Denver metropolitan area

text: The central part of the metropolitan statistical area (MSA) includes Denver and three immediately adjacent counties: Jefferson County to the west, Adams County to the north and east, and Arapahoe County to the south and east. The continuously urbanized area extends northwest into the City and County of Broomfield, bordering Jefferson and Adams counties, and south into Douglas County, adjoining Arapahoe County. Also included in the federally defined MSA are four rural counties: Elbert County on the southeastern prairie and Clear Creek, Gilpin, and Park counties in the Rocky Mountains.


title: Denver metropolitan area

text: The Denver-Aurora-Lakewood Metropolitan Statistical Area comprises ten counties. The sortable table below includes the following information:


title: Denver metropolitan area

text: The Denver Regional Council of Governments (DRCOG, pronounced Doctor Cog) is a regional planning and inter-governmental coordination organization in a nine-county region. The Scientific and Cultural Facilities District (SCFD) provides funding for scientific and cultural facilities in a seven-county region including:


title: Denver metropolitan area

text: In addition, the Regional Transportation District (RTD) provides mass transit, including a light rail system. In 2005 the RTD developed a twelve-year comprehensive plan, called "FasTracks", to build and operate rail transit lines and expand and improve bus service throughout the region.


title: Denver metropolitan area

text: The most prosperous parts of the area are in the south and the northwest, while the most industrialized areas are in the northeast, specifically in the northern part of Denver proper and extending to areas such as Commerce City in Adams County.


title: Denver metropolitan area

text: Changes in house prices for the area are publicly tracked on a regular basis using the Case–Shiller index; the statistic is published by Standard & Poor's and is also a component of S&P's 10-city composite index of the value of the residential real estate market. The Denver MSA is also home to one of the fastest growing tech scenes outside of Silicon Valley in the country.


title: Denver metropolitan area

text: The following table shows sports teams in the Denver metropolitan area that average more than 12,000 fans per game:


title: Denver metropolitan area

text: The center of the metropolitan area sits in a valley, the Denver Basin, and suffers from air pollution known colloquially as the "brown cloud", building up if the air is stagnant as it often is in the winter. Severity of pollution in this area has varied enormously over the years. In the late 1980s the area was frequently in violation of multiple National Ambient Air Quality Standards established by the United States Environmental Protection Agency (EPA). The Regional Air Quality Council (RAQC) was formed in 1989 to create plans to address the problem. Through a variety of measures the area's air quality was improved and in 2002 the EPA designated the area in compliance with all federal health-based air quality standards. Denver was the first major city in the United States to reach compliance with all six of these standards after previously violating five of them. Since then the EPA introduced a new standard for small particulates and made the existing ozone standard stricter. In 2003 the new ozone standard was frequently exceeded in the area and was occasionally exceeded as far away as Rocky Mountain National Park. The RAQC hopes to implement plans enabling the area to comply with the new standards by 2007.


title: Denver metropolitan area

text: Though Aurora, Boulder, Brighton, Broomfield, Denver, Lakewood, and Longmont have their own individual sister city relationships, the Denver Regional Council of Governments (DRCOG) as a whole has a sister city relationship with the Baghdad Governorate of Iraq.


title: Teletext

text: Teletext, or broadcast teletext, is a standard for displaying text and rudimentary graphics on suitably equipped television sets. Teletext sends data in the broadcast signal, hidden in the invisible vertical blanking interval area at the top and bottom of the screen. The teletext decoder in the television buffers this information as a series of "pages", each given a number. The user can display chosen pages using their remote control.


title: Teletext

text: In broad terms, it can be considered as Videotex, a system for the delivery of information to a user in a computer-like format, typically displayed on a television or a dumb terminal, but that designation is usually reserved for systems that provide bi-directional communication, such as Prestel or Minitel.


title: Teletext

text: Teletext was created in the United Kingdom in the early 1970s by John Adams, Philips' lead designer for video display units. Public teletext information services were introduced by major broadcasters in the UK, starting with the BBC's Ceefax service in 1974. It offered a range of text-based information, typically including news, weather and TV schedules. Also, paged subtitle (or closed captioning) information was transmitted using the same system. Similar systems were subsequently introduced by other television broadcasters in the UK and mainland Europe in the following years. Meanwhile, the UK's General Post Office introduced the Prestel system using the same display standards but run over telephone lines using bi-directional modems rather than the send-only system used with televisions.


title: Teletext

text: Teletext formed the basis for the World System Teletext standard (CCIR Teletext System B), an extended version of the original system. This standard saw widespread use across Europe starting in the 1980s, with almost all televisions sets including a decoder. Other standards were developed around the world, notably NABTS (CCIR Teletext System C) in the United States, Antiope (CCIR Teletext System A) in France and JTES (CCIR Teletext System D) in Japan, but these were never as popular as their European counterpart and most closed by the early 1990s.


title: Teletext

text: Most European teletext services continued to exist in one form or another until well into the 2000s when the expansion of the Internet precipitated a closure of some of them. However, many European television stations continue to provide teletext services and even make teletext content available via web and dedicated apps.


title: Teletext

text: The recent availability of digital television has led to more advanced systems being provided that perform the same task, such as MHEG-5 in the UK, and Multimedia Home Platform.


title: Teletext

text: Teletext is a means of sending text and simple geometric shapes to a properly equipped television screen by use of one of the "vertical blanking interval" lines that together form the dark band dividing pictures horizontally on the television screen. Transmitting and displaying subtitles was relatively easy. It requires limited bandwidth; at a rate of perhaps a few words per second. However, it was found that by combining even a slow data rate with a suitable memory, whole pages of information could be sent and stored on the TV for later recall.


title: Teletext

text: In the early 1970s work was in progress in Britain to develop such a system. The goal was to provide UK rural homes with electronic hardware that could download pages of up-to-date news, reports, facts and figures targeting UK agriculture. The original idea was the brainchild of Philips (CAL) Laboratories in 1970.


title: Teletext

text: In 1971, CAL engineer John Adams created a design and proposal for UK broadcasters. His configuration contained all the fundamental elements of classic teletext including pages of 24 rows with 40 characters each, page selection, sub-pages of information and vertical blanking interval data transmission. A major objective for Adams during the concept development stage was to make teletext affordable to the home user. In reality, there was no scope to make an economic teletext system with 1971 technology. However, as the low cost was essential to the project's long-term success, this obstacle had to be overcome.


title: Teletext

text: Meanwhile, the General Post Office (GPO), whose telecommunications division later became British Telecom, had been researching a similar concept since the late 1960s, known as Viewdata. Unlike "Teledata", a one-way service carried in the existing TV signal, "Viewdata" was a two-way system using telephones. Since the Post Office owned the telephones, this was considered to be an excellent way to drive more customers to use the phones.


title: Teletext

text: In 1972 the BBC demonstrated its system, now known as Ceefax ("seeing facts", the departmental stationery used the "Cx" logo), on various news shows. The Independent Television Authority (ITA) announced its own service in 1973, known as ORACLE (Optional Reception of Announcements by Coded Line Electronics). Not to be outdone, the GPO immediately announced a 1200/75 baud videotext service under the name Prestel (this system was based on teletext protocols, but telephone-based).


title: Teletext

text: The TV-broadcast based systems were originally incompatible; Ceefax displayed pages of 24 lines with 32 characters each, while ORACLE offered pages of 22 lines with 40 characters each. In other ways the standards overlapped; for instance, both used 7-bit ASCII characters and other basic details. In 1974 all the services agreed on a standard for displaying the information. The display would be a simple grid of text, with some "graphics characters" for constructing simple graphics. The standard did not define the delivery system, so both "Viewdata"-like and "Teledata"-like services could at least share the TV-side hardware (which at that point in time was quite expensive).


title: Teletext

text: Following test transmissions in 1973–74, towards the end of 1974 the BBC news department put together an editorial team of nine, including and led by editor Colin McIntyre, to develop a news and information service. Initially limited to 30 pages, the Ceefax service was later expanded to 100 pages and was launched formally in 1976. It was followed quickly by ORACLE and Prestel. Wireless World magazine ran a series of articles between November 1975 and June 1976 describing the design and construction of a teletext decoder using mainly TTL devices; however, development was limited until the first TV sets with built-in decoders started appearing in 1977.


title: Teletext

text: The ""Broadcast Teletext Specification"" was published in September 1976 jointly by the IBA, the BBC and the British Radio Equipment Manufacturers' Association. The new standard also made the term "teletext" generic, describing any such system. The standard was internationalised as "World System Teletext" (WST) by CCIR.


title: Teletext

text: By 1982 there were two million such sets, and by the mid-1980s they were available as an option for almost every European TV set, typically by means of a plug-in circuit board. It took another decade before the decoders became a standard feature on almost all sets with a screen size above 15 inches (Teletext is still usually only an option for smaller "portable" sets). From the mid-1980s both Ceefax and ORACLE were broadcasting several hundred pages on every channel, slowly changing them throughout the day.


title: Teletext

text: In 1986 WST was formalised as an international standard as CCIR Teletext System B. It was also adopted in many other European countries.


title: Teletext

text: Besides the US and UK developments, a number of similar teletext services were developed in other countries, some of which attempted to address the limitations of the initial British-developed system, by adding extended character sets or improving graphic abilities. For example, state-owned RAI launched its teletext service, called Televideo, in 1984, with support for Latin character set. Mediaset, the main commercial broadcaster, launched its Mediavideo Teletext in 1997. These developments are covered by the different World System Teletext Levels.


title: Teletext

text: In France, where the SECAM standard is used in television broadcasting, a teletext system was developed in the late 1970s under the name Antiope. It had a higher data rate and was capable of dynamic page sizes, allowing more sophisticated graphics. It was phased out in favour of World System Teletext in 1991.


title: Teletext

text: In North America NABTS, the North American Broadcast Teletext Specification, was developed to encoding NAPLPS teletext pages, as well as other types of digital data. NABTS was the standard used for both CBS's ExtraVision and NBC's very short-lived NBC Teletext services in the mid-1980s.


title: Teletext

text: Japan developed its own JTES teletext system with support for Chinese, Katakana and Hiragana characters. Broadcasts started in 1983 by NHK.


title: Teletext

text: In 1986 the four existing teletext systems were adopted into the international standard CCIR 653 (now ITU-R BT.653) as CCIR Teletext System A (Antiope), B (World System Teletext), C (NABTS) and D (JTES).


title: Teletext

text: The World Wide Web began to take over some of the functions of teletext from the late 1990s. However, due to its broadcast nature, Teletext remained a reliable source of information during times of crisis, for example during the September 11 terrorist attacks when webpages of major news sites became inaccessible because of the high demand.


title: Teletext

text: As the web matured, many broadcasters ceased broadcast of Teletext — CNN in 2006 and the BBC in 2012. In the UK the decline of Teletext was hastened by the introduction of digital television, though an aspect of teletext continues in closed captioning. In other countries the system is still widely used on standard-definition DVB broadcasts.


title: Teletext

text: Subtitling still continues to use teletext in these three countries with some providers switching to using image-based DVB subtitling for HD broadcasts. New Zealand solely uses DVB subtitling on terrestrial transmissions despite teletext still being used on internal SDI links.


title: Teletext

text: Teletext information is broadcast in the vertical blanking interval between image frames in a broadcast television signal, in numbered "pages". For example, a list of news headlines might appear on page 110; a teletext user would type "110" into the TV's remote control to view this page. The broadcaster constantly sends out pages in a sequence. There will typically be a delay of a few seconds from requesting the page and it being broadcast and displayed, the time being entirely dependent on the number of pages being broadcast. More sophisticated receivers use a memory buffer to store some or all of the teletext pages as they are broadcast, allowing almost instant display from the buffer. This basic architecture separates teletext from other digital information systems, such as the Internet, whereby pages are 'requested' and then 'sent' to the user – a method not possible given the one-way nature of broadcast teletext. Unlike the Internet, teletext is broadcast, so it does not slow down further as the number of users increases, although the greater number of pages, the longer one is likely to wait for each to be found in the cycle. For this reason, some pages (e.g. common index pages) are broadcast more than once in each cycle.


title: Teletext

text: Teletext is also used for carrying special packets interpreted by TVs and video recorders, containing information about subjects such as channels and programming.


title: Teletext

text: Teletext allows up to eight 'magazines' to be broadcast, identified by the first digit of the three-digit page number (1–8). Within each magazine there may theoretically be up to 256 pages at a given time, numbered in hexadecimal and prefixed with the magazine number – for example, magazine 2 may contain pages numbered 200-2FF. In practice, however, non-decimal page numbers are rarely used as domestic teletext receivers will not have options to select hex values A-F, with such numbered pages only occasionally used for 'special' pages of interest to the broadcaster and not intended for public view.


title: Teletext

text: The broadcaster constantly sends out pages in sequence in one of two modes: Serial mode broadcasts every page sequentially whilst parallel mode divides VBI lines amongst the magazines, enabling one page from each magazine to be broadcast simultaneously. There will typically be a delay of a few seconds from requesting the page and it being broadcast and displayed, the time is entirely dependent on the number of pages being broadcast in the magazine (parallel mode) or in total (serial mode) and the number of VBI lines allocated. In parallel mode, therefore, some magazines will load faster than others.


title: Teletext

text: A standard PAL signal contains 625 lines of video data per screen, broken into two "fields" containing half the lines of the whole image, divided as every odd line, then every even line number. Lines near the top of the screen are used to synchronize the display to the signal and are not seen on-screen. Data formatted in accordance with CEPT presentation layer protocol and data syntax standard is stored in these lines, where they are not visible, using lines 6–22 on the first field and 318–335 on the second field. The system does not have to use all of these lines; a unique pattern of bits allows the decoder to identify which lines contain data. Some teletext services use a great number of lines, others, for reasons of bandwidth and technical issues, use fewer.


title: Teletext

text: Teletext in the PAL B system can use the VBI lines 6–22 in first half image and 318–334 in the other to transmit 360 data bits including clock run-in and framing code during the active video period at a rate of using binary NRZ line coding. The amplitude for a "0" is black level ±2% and a "1" is 66±6% of the difference between black and peak white level. The clock run in consist of of "10" and the framing code is "11100100". The two last bits of the clock-run in shall start within from the negative flank of the line synchronization pulse.


title: Teletext

text: The rate is , i.e. the TV line frequency. Thus 625 × 25 × 444 = 6,937,500 Hz. Each bit will then be 144 ns long. The bandwidth amplitude is 50% at 3.5 MHz and 0% at 6 MHz.


title: Teletext

text: If the horizontal sync pulse during the vertical synchronization starts in the middle of the horizontal scan line. Then first interlace frame will be sent, otherwise, if vertical synchronization let the full video line complete the second interlace frame is sent.


title: Teletext

text: Like EIA-608 bits are transmitted in the order of LSB to MSB with odd parity coding of 7-bit character codes. However unlike EIA-608, the DVB version is transmitted the same way. For single bit error recovery during transmission, the packet address (page row and magazine numbers) and header bytes (page number, subtitle flag, etc.) use hamming code 8/4 with extended packets (header extensions) using hamming 24/18, which basically doubles the bits used.


title: Teletext

text: The commonly used standard B uses a fixed PAL subtitling bandwidth of 8,600 (7,680 without page/packet header) bits/s per field for a maximum of 32 characters per line per caption (maximum three captions – lines 19 – 21) for a 25 frame broadcast. While the bandwidth is greater than EIA-608, so is the error rate with more bits encoded per field. Subtitling packets use a lot of non-boxed spacing to control the horizontal positioning of a caption and to pad out the fixed packet. The vertical caption position is determined by the packet address.


title: Teletext

text: In the case of the Ceefax and ORACLE systems and their successors in the UK, the teletext signal is transmitted as part of the ordinary analog TV signal but concealed from view in the Vertical Blanking Interval (VBI) television lines which do not carry picture information. The teletext signal is digitally coded as 45-byte packets, so the resulting rate is 7,175 bits per second per line (41 7-bit 'bytes' per line, on each of 25 frames per second).


title: Teletext

text: A teletext page comprises one or more "frames", each containing a screen-full of text. The pages are sent out one after the other in a continual loop. When the user requests a particular page the decoder simply waits for it to be sent, and then captures it for display. In order to keep the delays reasonably short, services typically only transmit a few hundred frames in total. Even with this limited number, waits can be up to 30 seconds, although teletext broadcasters can control the speed and priority with which various pages are broadcast.


title: Teletext

text: Modern television sets, however, usually have built-in memory, often for a few thousand different pages. This way, the teletext decoder captures every page sent out and stores it in memory, so when a page is requested by the user it can be loaded directly from memory instead of having to wait for the page to be transmitted. When the page is transmitted again, the decoder updates the page in memory.


title: Teletext

text: The text can be displayed instead of the television image, or superimposed on it (a mode commonly called "mix"). Some pages, such as subtitles (closed captioning), are "in-vision", meaning that text is displayed in a block on the screen covering part of the television image.


title: Teletext

text: The original standard provides a monospaced 40×24 character grid. Characters are sent using a 7-bit codec, with an 8th bit employed for error detection. The standard was improved in 1976 (World System Teletext Level 1) to allow for improved appearance and the ability to individually select the color of each character from a palette of eight. The proposed higher resolution Level 2 (1981) was not adopted in Britain (in-vision services from Ceefax & ORACLE did use it at various times, however, though even this was ceased by the BBC in 1996), although transmission rates were doubled from two to four lines a frame.


title: Teletext

text: In the early 1980s, a number of higher extension levels were envisaged for the specification, based on ideas then being promoted for worldwide videotex standards (telephone dial-up services offering a similar mix of text and graphics).


title: Teletext

text: The most common implementation is Level 1.5, which supports languages other than English. Virtually any TV sold in Europe since the 1990s has support for this level. After 1994 some stations adopted Level 2.5 Teletext or "Hi-Text", which allows for a larger color palette and higher resolution graphics.


title: Teletext

text: The proposed higher content levels included geometrically specified graphics (Level 4), and higher-resolution photographic-type images (Level 5), to be conveyed using the same underlying mechanism at the transport layer. No TV sets currently implement the two most sophisticated levels.


title: Teletext

text: The Mullard SAA5050 was a character generator chip used in the UK teletext-equipped television sets. In addition to the UK version, several variants of the chip existed with slightly different character sets for particular localizations and/or languages. These had part numbers SAA5051 (German), SAA5052 (Swedish), SAA5053 (Italian), SAA5054 (Belgian), SAA5055 (U.S. ASCII), SAA5056 (Hebrew) and SAA5057 (Cyrillic). The type of decoder circuitry is sometimes marked on televisions as "CCT" ("Computer-Controlled Teletext"), or "ECCT" ("Enhanced Computer-Controlled Teletext").


title: Teletext

text: Besides the hardware implementations, it is also possible to decode teletext using a PC and video capture or DVB board, as well as recover historical teletext from self-recorded VHS tapes.