title: Italian Renaissance

text: In sculpture, the Florentine artist Donato di Niccolò di Betto Bardi, or Donatello, was among the earliest sculptors to translate classical references into marble and bronze. His second sculpture of "David" was the first free-standing bronze nude created in Europe since the Roman Empire.


title: Italian Renaissance

text: The period known as the High Renaissance of painting was the culmination of the varied means of expression and various advances in painting technique, such as linear perspective, the realistic depiction of both physical and psychological features, and the manipulation of light and darkness, including tone contrast, "sfumato" (softening the transition between colours) and "chiaroscuro" (contrast between light and dark), in a single unifying style which expressed total compositional order, balance and harmony. In particular, the individual parts of the painting had a complex but balanced and well-knit relationship to the whole. The most famous painters from this phase are Leonardo da Vinci, Raphael, and Michelangelo and their images, including Leonardo's "The Last Supper" and "Mona Lisa", Raphael's "The School of Athens" and Michelangelo's "Sistine Chapel Ceiling" are the masterpieces of the period and among the most widely known works of art in the world.


title: Italian Renaissance

text: High Renaissance painting evolved into Mannerism, especially in Florence. Mannerist artists, who consciously rebelled against the principles of High Renaissance, tend to represent elongated figures in illogical spaces. Modern scholarship has recognized the capacity of Mannerist art to convey strong (often religious) emotion where the High Renaissance failed to do so. Some of the main artists of this period are Pontormo, Bronzino, Rosso Fiorentino, Parmigianino and Raphael's pupil Giulio Romano.


title: Italian Renaissance

text: In Florence, the Renaissance style was introduced with a revolutionary but incomplete monument by Leone Battista Alberti. Some of the earliest buildings showing Renaissance characteristics are Filippo Brunelleschi's church of San Lorenzo and the Pazzi Chapel. The interior of "Santo Spirito" expresses a new sense of light, clarity and spaciousness, which is typical of the early Italian Renaissance. Its architecture reflects the philosophy of Renaissance humanism, the enlightenment and clarity of mind as opposed to the darkness and spirituality of the Middle Ages. The revival of classical antiquity can best be illustrated by the Palazzo Rucellai. Here the pilasters follow the superposition of classical orders, with Doric capitals on the ground floor, Ionic capitals on the "piano nobile" and Corinthian capitals on the uppermost floor. Soon, Renaissance architects favoured grand, large domes over tall and imposing spires, doing away with the Gothic style of the predating ages.


title: Italian Renaissance

text: In Mantua, Alberti ushered in the new antique style, though his culminating work, Sant'Andrea, was not begun until 1472, after the architect's death.


title: Italian Renaissance

text: The High Renaissance, as we call the style today, was introduced to Rome with Donato Bramante's Tempietto at San Pietro in Montorio (1502) and his original centrally planned St. Peter's Basilica (1506), which was the most notable architectural commission of the era, influenced by almost all notable Renaissance artists, including Michelangelo and Giacomo della Porta. The beginning of the late Renaissance in 1550 was marked by the development of a new column order by Andrea Palladio. Giant order columns that were two or more stories tall decorated the facades.


title: Italian Renaissance

text: During the Italian Renaissance, mathematics was developed and spread widely. As a result, some Renaissance architects used mathematical knowledge like calculation in their drawings, such as Baldassarre Peruzzi.


title: Italian Renaissance

text: In Italy, during the 14th century, there was an explosion of musical activity that corresponded in scope and level of innovation to the activity in the other arts. Although musicologists typically group the music of the Trecento (music of the 14th century) with the late medieval period, it included features which align with the early Renaissance in important ways: an increasing emphasis on secular sources, styles and forms; a spreading of culture away from ecclesiastical institutions to the nobility, and even to the common people; and quick development of entirely new techniques. The principal forms were the Trecento madrigal, the caccia, and the ballata. Overall, the musical style of the period is sometimes labelled as the "Italian ars nova." From the early 15th century to the middle of the 16th century, the centre of innovation in religious music was in the Low Countries, and a flood of talented composers came to Italy from this region. Many of them sang in either the papal choir in Rome or the choirs at the numerous chapels of the aristocracy, in Rome, Venice, Florence, Milan, Ferrara and elsewhere; and they brought their polyphonic style with them, influencing many native Italian composers during their stay.


title: Italian Renaissance

text: The predominant forms of sacred music during the period were the mass and the motet. By far the most famous composer of church music in 16th-century Italy was Palestrina, the most prominent member of the Roman School, whose style of smooth, emotionally cool polyphony was to become the defining sound of the late 16th century, at least for generations of 19th- and 20th-century musicologists. Other Italian composers of the late 16th century focused on composing the main secular form of the era, the madrigal; for almost a hundred years these secular songs for multiple singers were distributed all over Europe. Composers of madrigals included Jacques Arcadelt, at the beginning of the age, Cipriano de Rore, in the middle of the century, and Luca Marenzio, Philippe de Monte, Carlo Gesualdo, and Claudio Monteverdi at the end of the era. Italy was also a centre of innovation in instrumental music. By the early 16th-century keyboard improvisation came to be greatly valued, and numerous composers of virtuoso keyboard music appeared. Many familiar instruments were invented and perfected in late Renaissance Italy, such as the violin, the earliest forms of which came into use in the 1550s.


title: Italian Renaissance

text: By the late 16th century Italy was the musical centre of Europe. Almost all of the innovations which were to define the transition to the Baroque period originated in northern Italy in the last few decades of the century. In Venice, the polychoral productions of the Venetian School, and associated instrumental music, moved north into Germany; in Florence, the Florentine Camerata developed monody, the important precursor to opera, which itself first appeared around 1600; and the avant-garde, manneristic style of the Ferrara school, which migrated to Naples and elsewhere through the music of Carlo Gesualdo, was to be the final statement of the polyphonic vocal music of the Renaissance.


title: Italian Renaissance

text: Any unified theory of a renaissance, or cultural overhaul, during the European early modern period is overwhelmed by a massive volume of differing historiographical approaches. Historians like Jacob Burckhardt (1818–1897) have often romanticized the enlightened vision that Italian Renaissance writers have promulgated concerning their own narrative of denouncing the fruitlessness of the Middle Ages. By promoting the Renaissance as the definitive end to the "stagnant" Middle Ages, the Renaissance has acquired the powerful and enduring association with progress and prosperity for which Burckhardt's "The Civilization of the Renaissance in Italy" is most responsible. Modern scholars have objected to this prevailing narrative, citing the medieval period's own vibrancy and key continuities that link, rather than divide, the Middle Ages and the Renaissance.


title: Italian Renaissance

text: Elizabeth Lehfeldt (2005) points to the Black Death as a turning point in Europe that set in motion several movements that were gaining massive traction in the years before, and has accounted for many subsequent events and trends in Western civilization, such as the Reformation. Rather than see this as a distinct cutoff between eras of history, the rejuvenated approach to studying the Renaissance aims to look at this as a catalyst that accelerated trends in art and science that were already well developed. For example, Danse Macabre, the artistic movement using death as the focal point, is often credited as a Renaissance trend, yet Lehfeldt argues that the emergence of Gothic art during medieval times was morphed into Danse Macabre after the Black Death swept over Europe.


title: Italian Renaissance

text: Recent historians who take a more revisionist perspective, such as Charles Haskins (1860–1933), identify the hubris and nationalism of Italian politicians, thinkers, and writers as the cause of the distortion of the attitude towards the early modern period. In "The Renaissance of the Twelfth Century" (1927), Haskins asserts that it is human nature to draw stark divides in history in order to better understand the past. However, it is essential to understand history as continuous and constantly building off of the past. Haskins was one of the leading scholars in this school of thought, and it was his (along with several others) belief that the building blocks for the Italian Renaissance were all laid during the Middle Ages, calling on the rise of towns and bureaucratic states in the late 11th century as proof of the significance of this "pre-renaissance." The flow of history that he describes paints the Renaissance as a continuation of the Middle Ages that may not have been as positive of a change as popularly imagined. Many historians after Burckhardt have argued that the regression of the Latin language, economic recession, and social inequality during the Renaissance have been intentionally glossed over by previous historians in order to promote the mysticism of the era.


title: Italian Renaissance

text: Burckhardt famously described the Middle Ages as a period that was "seen clad in strange hues", promoting the idea that this era was inherently dark, confusing, and unprogressive. The term "middle" ages was first referred to by humanists such as Petrarch and Biondo, during the late 15th century, describing it as a period connecting an important beginning and an important end, and as a placeholder for the history that exists between both sides of the period. This period was eventually referred to as the "dark" ages in the 19th century by English historians, which has further tainted the narrative of medieval times in favour of promoting a positive feeling of the individualism and humanism that spurred from the Renaissance.


title: Forged in Fire

text: Forged in Fire is an American competition series that airs on the History channel and is produced by Outpost Entertainment, a Leftfield Entertainment company.


title: Forged in Fire

text: In each episode, four bladesmiths compete in a three-round elimination contest to forge bladed weapons, with the overall winner receiving $10,000 and the show's championship title "Forged in Fire Champion". The series has a host (formerly Wil Willis for the first seven seasons, currently hosted by Grady Powell) and a three-judge panel consisting of J. Neilson (Jason Knight during portions of season 3 and 4; Ben Abbott during portions of season 4th, 5th, 6th and remaining in the 7th season), David Baker, and Doug Marcaida: experts in weapon making, history and use.


title: Forged in Fire

text: The History channel ordered an initial eight episodes of the series with the first program premiering on Monday, June 22, 2015, at 10pm ET. Season two premiered on February 16, 2016, and increased to 10 episodes. The third season premiered with a "Champion of Champions" match on August 23, 2016, and was announced as having 16 episodes. The fourth season premiered on April 11, 2017, with a "Judges' Pick" episode in which the four judges (Neilson, Knight, Baker, Marcaida) each selected one smith from past seasons to compete again. The fifth season premiered on March 7, 2018. The sixth season premiered on February 6, 2019. The seventh season premiered on October 9, 2019, and expanded into May 6, 2020. The eighth season premiered on November 18, 2020.


title: Forged in Fire

text: The set, referred to as "The Forge," is stocked with a wide range of metalworking equipment, including propane forges, coal forges, grinders, power hammers, and hydraulic presses. Medical personnel are present to treat any injuries or other health problems and may, at their discretion, disqualify smiths who are unable to continue safely. At the end of each round, the smith whose weapon is judged to be the least satisfactory must surrender it and leave the competition.


title: Forged in Fire

text: In a typical episode, the four smiths are presented with a quantity of steel that they must use in the first round to forge a blade in a style of their choosing. In some episodes, they all begin with the same starting material; in others, they may choose from an assortment of metal objects or must salvage their material from a source such as a junked car or lawnmower. The host states one set of criteria concerning blade or blade/tang length, and often a second set for a feature that must be incorporated, such as serrations or a fuller groove. The smiths are given 10 minutes to sketch out their designs, followed by three hours to forge the blades; they need not adhere to their original designs. Once the time expires, the judges evaluate the blades based on the host's criteria and inspect their craft, quality, and design, then deliberate privately before announcing their decision. Any smiths who fail to meet the criteria or who fail to turn in a blade at all are subject to immediate elimination.


title: Forged in Fire

text: For the second round, the three remaining smiths are given an additional two (originally three) hours to turn their blades into fully operational weapons. They must attach a handle, choosing from a range of provided materials, and incorporate any additional special features stated by the host. They must also grind, sharpen, and polish the blades, and may address any flaws or issues pointed out by the judges in the first round, if they choose to do so. After the time expires, the judges put each weapon through a series of tests to gauge properties such as sharpness, durability, and ease of use. For these tests, the weapons are used to chop/slash/stab objects that include ropes, ice blocks, animal bones/carcasses, and metal plumbing pipes. If one weapon suffers a catastrophic failure, defined as damage that renders it unsafe or ineffective for further testing, its maker is immediately disqualified. In the case of catastrophic failure by multiple weapons, the worst performer is eliminated. The judges may, at their discretion, choose not to subject a weapon to a particular test if it is sufficiently cracked or flawed.


title: Forged in Fire

text: In the third round, the two remaining smiths are shown a historically significant (and technically difficult) weapon, mostly prepared by David Baker, and are given four (originally five) days to create a version of it. They return to their home forges to do the work and must comply with any specifications set by the host. Afterward, they return to the Forge and submit their weapons for testing against objects and environments similar to the historical scenarios in which they were typically used. Based on the test results, the judges select one smith to receive the $10,000 prize and the day's championship title.


title: Forged in Fire

text: Tim Healy and Steve Ascher are executive producers for History. Jodi Flynn, Brent Montgomery, David George, Shawn Witt and Simon Thomas are executive producers for Outpost Entertainment. Healy observed the demonstration, and later the filming, from the sidelines. Healy says that the inspiration for "Forged in Fire" came from his and other developers' love of food competition shows such as "Chopped" and "Iron Chef". However, in order to appeal to the History channel's audience, they decided to have the competition focus on historical weaponry.


title: Forged in Fire

text: Typically, candidates for "Forged in Fire" episodes go through a casting call and screening process before appearing and competing on the show. For example, Doug Marcaida shared a casting call to his "Facebook" page on October 18, 2021, seeking "...metal workers to forge iconic edged weapons from History!". After applying to be on the show, the potential competitors are interviewed by video and phone; asked questions about their metallurgy knowledge, experience, and skills; and undergo background checks. Sometimes, the entrants are asked to build a weapon with particular specifications, with progress pictures being sent to and analyzed by the show's producers before being considered to compete on an episode.


title: Forged in Fire

text: On occasion, former contestants are invited back to the show to participate in another competition. As examples, bladesmiths have reappeared and competed in a military branch tournament, "Second Chance Tournament", or a broken blade "revenge" episode, just to name a few.


title: Forged in Fire

text: "Forged in Fire" episodes are filmed at Brooklyn Fireproof Stages in Brooklyn, New York City, New York, in a safe, professional environment.


title: Forged in Fire

text: The set is composed of a large judge's table from where the judges spectate throughout the episode, 3 or 4 main work tables for contestants, large shelving units dubbed the "pantry" for various handle materials, and large quantities of various metal types, grades, sources, and shapes. The rest of the set floor is spotted with other work stations for tools and equipment such as Venturi forges (made and supplied by Majestic Forge), a variety of hammers, steel files, wire brushes, anvils, foot-operated power hammers, hydraulic presses, electric buffer wheels, grinding wheels, vises, welding machines, and other hand and electric tools. Safety equipment is also found throughout the set and is used during construction and testing of weapons.


title: Forged in Fire

text: The winning blades from each episode are showcased on the "Winners Wall" of the filming studio. Some of those blades can be seen on the wall behind the standing contestants during testing portions of various episodes. As the show's sign of respect and gratitude for the participant's effort, time, and labor that went into making each weapon, non-winning blades are returned to the competitors after the respective episode has aired.


title: Forged in Fire

text: The "Master & Apprentice" episode in Season 4 featured four master/apprentice pairs of smiths. Only one member of each pair was allowed to work at any time, trading off every 30 minutes in the first two rounds and every day in the third. The non-working member was allowed to offer advice. For this episode, the forging time in the first round was extended to three and a half hours.


title: Forged in Fire

text: The "Ultimate Champions Edition" (Season 4) and "Rookies Edition" (Season 5) each featured five smiths instead of four. The smiths were required to forge a particular type of blade at their homes and bring those weapons to the studio for a preliminary test. One smith was eliminated based on the results of this test, after which the competition proceeded through the normal three rounds.


title: Forged in Fire

text: On October 3, 2018, a five-week Invitational Tournament premiered, consisting of four preliminary heats and a finale. Four smiths with a particular specialty (farrier, armorer, blacksmith, metalworker) competed in each preliminary heat, with the winners advancing to the finale for a $50,000 prize. Dave Parthemore of Connecticut won.


title: Forged in Fire

text: A "Battle of the Branches" tournament began on May 8, 2019, with four smiths from a different branch of the United States armed services (Army, Navy, Air Force, Marines) competing in each preliminary heat.


title: Forged in Fire

text: During the 2019 season, "Forged in Fire" aired "enhanced" episodes called "", which featured bonus scenes of older episodes with expert tips and techniques from the judges like Dave Baker explaining what happened to each blade during the weapon tests. Each episode was two hours long (made up of 2 older one-hour episodes), highlighting blade themes such as "Revolutionary War Swords" and "Curved Blades", etc.


title: Forged in Fire

text: On May 13, 2020, a special episode titled "" aired at 8/9c on History. The judges J. Neilson, Dave Baker, and Doug Marcaida, were in the "hot seat" as fans asked them questions about the show, their personal lives, and bladesmithing techniques.


title: Forged in Fire

text: On November 24, 2021, a special episode titled "Bladesgiving" aired at 10 p.m. EST on History. Before the Thanksgiving fest, comes the hunt in which the "Forged In Fire" team showcased classic hunting weapons. The episode relived five showdowns between championship hunting blades, bows and spears made by some of the forge's bladesmiths.


title: Forged in Fire

text: Aside from viewing "Forged in Fire" episodes on History's cable channel and its internet website, there are other subscription options to watch the show. On October 1, 2021, seasons 1, 2, 3, 6, and 7 were added to Discovery+, with season 4 being added to the streaming platform on February 1, 2022. On November 21, 2021, Netflix began airing episodes, albeit one season at a time. There are three seasons (87 episodes) available on Hulu. Episodes from all seasons are available on iTunes, Amazon Prime Video, Google Play, and Vudu on a "Buy/Rent" basis.


title: Forged in Fire

text: In the city of Cohoes, New York near Albany, a man, inspired by the series, tried to forge a piece of metal over a fire in a barrel near his home. He caused a fire that destroyed three residential buildings and damaged 28 others.


title: Forged in Fire

text: On April 17, 2018, a spin-off series titled "Forged in Fire: Knife or Death" premiered on History. This series is hosted by Bill Goldberg and co-hosted by Tu Lam, a martial arts expert and retired member of the Green Berets.


title: Forged in Fire

text: On June 3, 2020, another spin-off series titled "Forged in Fire: Beat the Judges" premiered on History, hosted by Willis. On each episode, three previous "Forged in Fire" champions return to compete for an opportunity to face one judge (Neilson, Baker, or Abbott) and win another $10,000. For the first round (level 1), the three smiths each brought one weapon to the Forge in a style of their choosing and created at their home forges, and submit them for testing by Doug Marcaida. The second round (level 2) follows the same format as the third round in a typical "Forged in Fire" episode. However, the two remaining smiths are given only three days to forge an example of the featured weapon at their home forges. In the third round (level 3), the last remaining smith and the competing judge are given eight hours to create a fully functional example of a particular weapon type in the Forge, including handle fitting and grinding/sharpening/polishing. The other judges then test the weapons and choose the $10,000 winner. The competing judge is announced at the start of the third round; if he wins, the prize is donated to the charity of his choice. J. Neilson (Melanoma Foundation), Dave Baker (Breast Cancer Research), and Ben Abbott (Black Horse Forge: free blacksmithing classes to First Responders and Veterans).


title: Elizabeth Gilbert

text: Elizabeth Gilbert (born July 18, 1969) is an American journalist and author. She is best known for her 2006 memoir, "Eat, Pray, Love", which has sold over 12 million copies and has been translated into over 30 languages. The book was also made into a film of the same name in 2010.


title: Elizabeth Gilbert

text: Gilbert was born in Waterbury, Connecticut in 1969. Her father, John Gilbert, was a chemical engineer at Uniroyal; her mother, Carole, was a nurse and established a Planned Parenthood clinic.


title: Elizabeth Gilbert

text: When Gilbert was four, her parents bought a Christmas tree farm in Litchfield, Connecticut. The family lived in the country with no neighbors; they did not own a television or record player. Consequently, the family read a great deal, and Gilbert and her older sister Catherine Gilbert Murdock entertained themselves by writing books and plays. Gilbert has said that her parents were not hippies but modern pioneers, "My parents are the only people I've ever known who made their own goat's-milk yogurt and voted for Reagan twice. That's a Venn diagram that doesn't include anyone else."


title: Elizabeth Gilbert

text: Gilbert attended New York University. She resisted taking literature classes and writing workshops and stated in an interview, "I never thought that the best place for me to find my voice would be in a room filled with twenty other people trying to find their voices. I was a big moralist about it, actually. I felt that if I was writing on my own, I didn't need a class, and if I wasn't writing on my own, I didn't deserve one." Instead of attending graduate school, Gilbert decided to create her own education through work and travel.


title: Elizabeth Gilbert

text: After college, Gilbert moved to Philadelphia and worked as a waitress or bartender to save up enough money to travel. Gilbert stated in a "New York Times" interview that she was influenced by Ernest Hemingway's early career, and his short story collection, "In Our Time". Gilbert believed that writers find stories not in a seminar room but by investigating the world. She held various jobs including a trail cook, bartender, and waitress while storing up experiences for her writing.


title: Elizabeth Gilbert

text: "Esquire" published Gilbert's short story "Pilgrims" in 1993, under the headline "The Debut of an American Writer". She was the first unpublished short story writer to debut in "Esquire" since Norman Mailer. This led to steady work as a journalist for a variety of national magazines, including "Spin", "GQ", "The New York Times Magazine", "Allure", "Real Simple", and "Travel + Leisure". As stated in the memoir "Eat, Pray, Love", Gilbert made a career as a highly paid freelance writer.


title: Elizabeth Gilbert

text: Her 1997 "GQ" article, "The Muse of the Coyote Ugly Saloon", a memoir of Gilbert's time as a bartender at the very first Coyote Ugly table dancing bar located in the East Village section of New York City, was the basis for the feature film "Coyote Ugly" (2000). She adapted her 1998 "GQ" article, "The Last American Man" into a biography of the modern woodsman and naturalist Eustace Conway in "The Last American Man". "The Ghost", a profile of Hank Williams III published by "GQ" in 2000, was included in "Best American Magazine Writing 2001".


title: Elizabeth Gilbert

text: Gilbert's first book, "Pilgrims" (Houghton Mifflin 1997), a collection of short stories, received the Pushcart Prize and was a finalist for the PEN/Hemingway Award. This was followed by her novel "Stern Men" (Houghton Mifflin 2000), selected by "The New York Times" as a "Notable Book". In 2002, she published "The Last American Man" (2002), which was nominated for National Book Award in non-fiction.


title: Elizabeth Gilbert

text: In 2006, Gilbert published "Eat, Pray, Love: One Woman's Search for Everything Across Italy, India and Indonesia" (Viking, 2006), a chronicle of her year of "spiritual and personal exploration" spent traveling abroad. She financed her world travel for the book with a $200,000 publisher's advance after pitching the concept in a book proposal. The best-seller has been critiqued by some writers as "priv-lit" ("a literature of privilege") and a "calculated business decision". The memoir appeared on the "New York Times" Best Seller list of nonfiction in the spring of 2006, and was still #2 on the list 88 weeks later, in October 2008. It was optioned for a film by Columbia Pictures, which released "Eat Pray Love", starring Julia Roberts as Gilbert, on August 13, 2010. Gilbert appeared on "The Oprah Winfrey Show" in 2007, and has reappeared on the show to further discuss the book, her philosophy, and the film. She was named one of the 100 most influential people in the world by "Time" magazine, and named to Oprah's "SuperSoul 100" list of visionaries and influential leaders.


title: Elizabeth Gilbert

text: Gilbert's fifth book, "", was released by Viking Press in January 2010. The book is somewhat of a sequel to "Eat, Pray, Love" in that it takes up Gilbert's life story where her bestseller left off. "Committed" also reveals Gilbert's decision to marry Jose Nunes (referred to in the book as Felipe), a Brazilian man she met in Manu, Indonesia. The book is an examination of the institution of marriage from several historical and modern perspectives—including those of people, particularly women, reluctant to marry. In the book, Gilbert also includes perspectives on same-sex marriage and compares this to interracial marriage prior to the 1970s.


title: Elizabeth Gilbert

text: In 2012, she republished "At Home on the Range", a 1947 cookbook written by her great-grandmother, food columnist Margaret Yardley Potter. Gilbert published her second novel, "The Signature of All Things", in 2013.


title: Elizabeth Gilbert

text: In 2015, Gilbert published "Big Magic: Creative Living Beyond Fear", a self-help book that provides instructions on how to live a life as creative as hers. The book is broken down into six sections: Courage, Enchantment, Permission, Persistence, Trust, and Divinity. Advice in "Big Magic" focuses on overcoming self-doubt, avoiding perfectionism, and agenda setting, among other topics. Gilbert continued the work started in "Big Magic" with her "Magic Lessons" podcast in which she interviews famous creatives including Brene Brown and Sarah Jones.


title: Elizabeth Gilbert

text: A review of "Big Magic" in "Slate" stated that most of the advice in the book is matter-of-fact, but that, "Gilbert comes bearing reports from a new world where untold splendors lie waiting for those bold and hard-working enough to claim them. What's unclear is how many could successfully follow on her trail." "The Seattle Times" described the book as, "funny, perceptive and full of down-to-earth advice."


title: Elizabeth Gilbert

text: In an interview, Gilbert mentioned "The Wizard of Oz" with nostalgia, adding, "I am a writer today because I learned to love reading as a child—and mostly on account of the Oz books..." She has said she was particularly influenced by Charles Dickens, and has noted this in many interviews. She identifies Marcus Aurelius's "Meditations" as her favorite book on philosophy. She also declared Jack Gilbert as "the poet laureate of my life" when she succeeded him as a writer-in-residence at the University of Tennessee in 2006.


title: Elizabeth Gilbert

text: In 2015, Gilbert and several other authors including Cheryl Strayed participated in fundraising efforts for Syrian refugees which raised over $1 million in 31 hours. In 2016, Gilbert shared a video of herself singing a karaoke version of Bonnie Tyler's "Total Eclipse of the Heart" to raise money for BlinkNow Foundation, an organization inspired in part by "Eat, Pray, Love".


title: Elizabeth Gilbert

text: In a 2015 article for "The New York Times" titled "Confessions of a Seduction Addict", Gilbert wrote that she "careened from one intimate entanglement to the next—dozens of them—without so much as a day off between romances." She acknowledged, "Seduction was never a casual sport for me; it was more like a heist, adrenalizing and urgent. I would plan the heist for months, scouting out the target, looking for unguarded entries. Then I would break into his deepest vault, steal all his emotional currency and spend it on myself." She realised that, "I might indeed win the man eventually. But over time (and it wouldn't take long), his unquenchable infatuation for me would fade, as his attention returned to everyday matters. This always left me feeling abandoned and invisible; love that could be quenched was not nearly enough love for me".


title: Elizabeth Gilbert

text: Gilbert was married to Michael Cooper, whom she met while working at the Coyote Ugly Saloon, from 1994 to 2002. The marriage ended when Gilbert left Cooper for another man.


title: Elizabeth Gilbert

text: In 2007, Gilbert married José Nunes, whom she met in Bali while on the travels she describes in "Eat, Pray, Love". Gilbert and Nunes lived in Frenchtown, New Jersey; together they ran a large Asian import store called Two Buttons until they sold it in 2015.


title: Elizabeth Gilbert

text: On July 1, 2016, Gilbert announced on her Facebook page that she and Nunes were separating, saying that the split was "very amicable" and that their reasons were "very personal". On September 7, 2016, Gilbert published a Facebook post saying that she was in a relationship with her female best friend, writer Rayya Elias, and that this relationship was related to the breakup of her marriage. The relationship began because Gilbert realized her feelings for Elias following Elias's terminal cancer diagnosis. On June 6, 2017, the two celebrated a commitment ceremony with close family and friends. The ceremony was not legally binding. Elias died on January 4, 2018.


title: Elizabeth Gilbert

text: On March 25, 2019, Gilbert posted on Instagram that she was in a relationship with United Kingdom-born photographer Simon MacArthur, who was also a close friend of Elias. In an interview in February 2020, she shared that she and MacArthur were no longer together, calling the relationship "short lived".


title: MasterChef Australia (series 12)

text: The twelfth series of the Australian cooking game show MasterChef Australia, also known as MasterChef Australia: Back To Win, premiered on 13 April 2020. It is the first series to feature series four winner Andy Allen, Melissa Leong and Jock Zonfrillo serving as judges, after the departure of Gary Mehigan, George Calombaris and Matt Preston in the previous season. This series involves former high-achieving contestants from the past eleven series of "MasterChef Australia", returning for another chance at the title of 'MasterChef' and the A$250,000 prize.


title: MasterChef Australia (series 12)

text: Applications for contestants for the twelfth series of "MasterChef Australia" opened in May 2019. However, plans were changed when returning contestants were brought onboard instead of new contestants. Katy Perry appeared as a guest judge in an immunity challenge based around her song "Hot N Cold", which is the theme song of the show.


title: MasterChef Australia (series 12)

text: This series was won by Emelia Jackson in the grand finale against Laura Sharrad, broadcast on 20 July 2020.


title: MasterChef Australia (series 12)

text: Gary Mehigan, George Calombaris and Matt Preston departed the show in 2019 and were replaced with new judges Andy Allen, Melissa Leong and Jock Zonfrillo.


title: MasterChef Australia (series 12)

text: In this series, the typical "MasterChef" weekly format was slightly changed from prior series. Mondays now feature a "Team Challenge" with the losing team facing Tuesday's "Pressure Test" elimination. Wednesdays feature a "Mystery Box" with the best cooks competing in the "Immunity Challenge" on Thursday, in which one contestant will be granted immunity from the upcoming elimination. All the other contestants then head into the "All-In Elimination Challenge" on Sunday. In addition, only one Immunity Pin was up for grabs this season; it was awarded to Dani Venn in the first episode of the series. A new format schedule was debuted on 14 June, with the show beginning to air only three nights a week. Mondays featured the "Mystery Box", Tuesdays featured the "Immunity Challenge", and Sundays featured the "All-In Elimination Challenge".


title: MasterChef Australia (series 12)

text: Amidst the COVID-19 pandemic, production of the show continued while following government regulations. This includes the observance of social distancing, having individual plates for each judge during tasting, and the use of gloves when handling ingredients. In addition, the number of crew on set has been reduced by half, and outside challenges and guests have been dialled back. The new measures debuted on 25 May 2020.


title: MasterChef Australia (series 12)

text: Unlike previous seasons, there was no mid-way "second chance" return challenge for eliminated contestants; all eliminated contestants had no chance to return to the season.


title: MasterChef Australia (series 12)

text: The 24 returning contestants were announced on 19 February 2020. Other past contestants such as Derek Lau, Sarah Todd, and Alvin Quah were later confirmed to have been invited to compete in the series, but refused for various reasons.


title: MasterChef Australia (series 12)

text: In March 2020, Ben Ungermann suddenly left the series after being arrested in a matter unrelated to the show. His departure was announced on 17 May 2020. Most charges were dropped when Ungermann pleaded guilty to a single count of common law assault, avoiding a criminal conviction.


title: MasterChef Australia (series 12)

text: Despite the largely positive overall reception, the series has been met with some skepticism from viewers, mostly through social media, concerning the judges' apparent favouritism towards certain contestants. The most prominent instance of this has centered around contestant Laura Sharrad, who worked in judge Jock Zonfrillo's restaurant for two years following her Series 6 appearance, thus sparking concerns that Zonfrillo may therefore be biased towards her. Other criticism has focused largely on Laura's supposed tendency to cook pasta dishes repeatedly, despite the fact that less than half her dishes could be classified as such. The judges' decision to award Weekly Immunity to Laura, rather than Poh, in Episode 50, was met with backlash from viewers, who felt that Poh's effort was evidently superior. Laura spoke out about her controversy, citing the numerous non-pasta dishes she has cooked on the show and claiming that having to cook for her former employer has made the competition harder, rather than easier, for her. Emelia Jackson called the online hate "narrow-minded".


title: MasterChef Australia (series 12)

text: Other accusations have attacked the judges' apparent reluctance to eliminate contestants Poh Ling Yeow and Reynold Poernomo, both of whom are considered fan favourites, and, therefore, beneficial to the show's viewership. Notably, contestant Tessa Boersma’s elimination stirred controversy and prompted allegations of bias towards Reynold. On the other hand, fans of Reynold called the finale "rigged" because Reynold was not in it.


title: Emma Watkins

text: Emma Olivia Watkins (born 21 September 1989) is an Australian singer, actress, and dancer, best known as a former member of the children's group the Wiggles. She debuted her own children's entertainment character, Emma Memma, in 2022; an accompanying television series entitled "Emma Memma: Sing. Dance. Sign." is in development.


title: Emma Watkins

text: Watkins started ballet when she was four. She saw the Wiggles perform Irish dancing and later studied other styles of dance, including jazz, hip hop, tap and contemporary. She attended The McDonald College, a performing arts school; won a full scholarship at the Sydney Film School; and completed a certificate specialising in musical theatre at ED5 International in Sydney. Watkins earned a master's degree in Media Arts and Production at the University of Technology Sydney. She has taught dance to children since she was in high school. She has also performed in Bollywood films, learned drums and other percussion instruments, was crowned Miss Granny Smith Apples in 2009, and was learning Auslan, the Australian sign language, by 2012. As of 2021, she was doing her PhD research on sign language and dance.


title: Emma Watkins

text: In 2010, Watkins began performing with the Wiggles, first as Fairy Larissa and then as Wags the Dog, Dorothy the Dinosaur, and as a Wiggly Dancer. She used her film skills during tours with the group, providing them with video and editing services. In May 2012, the Wiggles announced that Watkins would become the first female Wiggle, replacing founding member Greg Page as the Yellow Wiggle. The original members stated that they chose Watkins because she was the most qualified for the job, and commented that it was "a strategy for marketing the Wiggles into the next generation".


title: Emma Watkins

text: Lisa Tolin of the "Associated Press" called Watkins a strong role model for girls, and reported that her fans came to concerts dressed like her and that they gave her homemade bows, which had become part of her signature look. Because of her popularity, the company produced a new television series entitled "Emma!", featuring Watkins as a solo performer, which aired in 2015. Up to 80% of the audience at Wiggles concerts would emulate her costuming and wear yellow; by 2021 it was estimated that 50% of the group's merchandising was specific to the "Emma" brand.


title: Emma Watkins

text: In September 2019, it was announced that Watkins would host weekend afternoon programs on Sydney and Melbourne radio station smoothfm. In October 2020, Watkins appeared in the music video for "Back 2 Back" by Samantha Jade. At the 2020 ARIA Music Awards in November, she joined an ensemble of Australian women singers to perform "I Am Woman" as a tribute to its singer and songwriter, Helen Reddy.


title: Emma Watkins

text: It was reported through corporate filings that Watkins had acquired approximately 8% ownership of the Wiggles' brand as well as a company directorship in June 2018. Watkins announced her departure from the Wiggles in October 2021 and was replaced by Tsehay Hawkins.


title: Emma Watkins

text: In early 2022, Watkins hinted at the introduction of a new children's entertainment character, Emma Memma, through her social media. The new character was designed to incorporate elements of song, dance and sign language. Toronto-based company Headspinner Productions announced their partnership with Watkins in July 2022 to debut the character in a new pre-school television series entitled "Emma Memma: Sing. Dance. Sign". Watkins was appointed as an executive producer for the series, to be produced through her company Apricot Sea. The series is expected to begin filming in early 2023 for release later in the year. The character and its design were officially revealed in July; music videos were subsequently released through YouTube.


title: Emma Watkins

text: Watkins also competed on the fourth season of the Australian version of The Masked Singer as "Zombie" placing eighth.


title: Emma Watkins

text: Watkins and fellow Wiggles performer Lachlan Gillespie were married on 9 April 2016 at Hopewood House in Bowral, New South Wales. On 3 August 2018, Watkins and Gillespie announced their separation.


title: Emma Watkins

text: In April 2018, Watkins was forced to withdraw from several shows, suffering from pain caused by severe endometriosis. She underwent surgery after being diagnosed with Stage IV endometriosis. Her specialist, Professor Jason Abbott, believes that Watkins' speaking out about her diagnosis helped raise awareness of the condition.


title: Emma Watkins

text: On 5 April 2021, Watkins announced her engagement to Oliver Brian, a musician who works with the Wiggles. They had begun dating in December 2019. On 2 May 2022, she and Brian were married.


title: Rifle

text: A rifle is a long-barreled firearm designed for accurate shooting, with a barrel that has a helical pattern of grooves (rifling) cut into the bore wall. In keeping with their focus on accuracy, rifles are typically designed to be held with both hands and braced firmly against the shooter's shoulder via a buttstock for stability during shooting. Rifles are used extensively in warfare, law enforcement, hunting, shooting sports, and crime.


title: Rifle

text: The term was originally rifled gun, with the verb "rifle" referring to the early modern machining process of creating groovings with cutting tools. By the 20th century, the weapon had become so common that the modern noun "rifle" is now often used for any long-shaped handheld ranged weapon designed for well-aimed discharge activated by a trigger (e.g., personnel halting and stimulation response rifle, which is actually a laser dazzler).


title: Rifle

text: Like all typical firearms, a rifle's projectile (bullet) is propelled by the contained deflagration of a combustible propellant compound (originally black powder, later cordite, and now nitrocellulose), although other propulsive means are used, such as compressed air in air rifles, which are popular for vermin control, small game hunting, competitive target shooting and casual sport shooting ("plinking").


title: Rifle

text: The distinct feature that separates a rifle from the earlier smoothbore long guns (e.g., arquebuses, muskets) is the rifling within its barrel. The raised areas of a barrel's rifling are called "lands"; they make contact with and exert torque on the projectile as it moves down the bore, imparting a spin. When the projectile leaves the barrel, this spin persists and lends gyroscopic stability to the projectile due to conservation of angular momentum, increasing accuracy and hence effective range. Early long rifles were muzzle-loaders firing spherical balls; the introduction of breech-loading allowed the use of elongated and aerodynamically efficient bullets, which did not yaw or tumble significantly in flight due to the spin.


title: Rifle

text: Historically, rifles only fired a single projectile with each squeeze of the trigger. Modern rifles are commonly classified as single-shot, bolt-action, semi-automatic, or automatic. Single-shot, bolt-action, and semi-automatic rifles are limited by their designs to fire a single shot for each trigger pull. Only automatic rifles are capable of firing more than one round per trigger squeeze; however, some automatic rifles are limited to fixed bursts of two, three, or more rounds per squeeze.


title: Rifle

text: Modern automatic rifles overlap to some extent in design and function with machine guns. In fact, many light machine guns (such as the Russian RPK) are adaptations of existing automatic rifle designs. A military's light machine guns are typically chambered for the same caliber ammunition as its service rifles. Generally, the difference between an automatic rifle and a machine gun comes down to weight, cooling system, and ammunition feed system. Rifles, with their relatively lighter components (which overheat quickly) and smaller capacity magazines, are incapable of sustained automatic fire in the way that machine guns are; they trade this capability in favor of increased mobility. Modern military rifles are fed by magazines, while machine guns are generally belt-fed. Many machine guns allow the operator to quickly exchange barrels in order to prevent overheating, whereas rifles generally do not. Most machine guns fire from an open bolt in order to reduce the danger of "cook-off", while almost all rifles fire from a closed bolt for accuracy. Machine guns are often crewed by more than one soldier; the rifle is an individual weapon.


title: Rifle

text: The term "rifle" is sometimes used to describe larger rifled crew-served weapons firing explosive shells, for example, recoilless rifles and naval rifles.


title: Rifle

text: In many works of fiction a rifle refers to any weapon that has a stock and is shouldered before firing, even if the weapon is not rifled or does not fire solid projectiles (e.g., a "laser rifle").


title: Rifle

text: The origins of rifling are as difficult to trace, but some of the earliest European experiments seem to have been carried out during the 15th century. Archers had long realized that a twist added to the tail feathers of their arrows gave them greater accuracy. Early muskets produced large quantities of smoke and soot, which had to be cleaned from the action and bore of the musket frequently, either through the action of repeated bore scrubbing, or a deliberate attempt to create "soot grooves" that would allow for more shots to be fired from the firearm. Some of the earliest examples of European grooved gun barrels were reportedly manufactured as early as 1440 and further developed by Gaspard Kollner of Vienna circa 1498, although other scholars allege they were a joint effort between Kollner and Augustus Kotter of Nuremberg circa 1520. Military commanders preferred smoothbore weapons for infantry use because rifles were much more prone to problems due to powder fouling the barrel and because they took longer to reload and fire than muskets.


title: Rifle

text: Rifles were created as an improvement in the accuracy of smoothbore muskets. In the early 18th century, Benjamin Robins, an English mathematician, realized that an elongated bullet would retain the momentum and kinetic energy of a musket ball, but would slice through the air with greater ease. The black powder used in early muzzle-loading rifles quickly fouled the barrel, making loading slower and more difficult. The greater range of the rifle was considered to be of little practical use since the smoke from black powder quickly obscured the battlefield and made it almost impossible to aim the weapon from a distance. Since musketeers could not afford to take the time to stop and clean their barrels in the middle of a battle, rifles were limited to use by sharpshooters and non-military uses like hunting.


title: Rifle

text: Muskets were smoothbore, large caliber weapons using spherical ammunition fired at relatively low velocity. Due to the high cost and great difficulty of precision manufacturing, and the need to load readily from the muzzle, the musket ball was a loose fit in the barrel. Consequently, on firing the ball bounced off the sides of the barrel when fired and the final direction on leaving the muzzle was unpredictable.


title: Rifle

text: The performance of early muskets defined the style of warfare at the time. Due to the lack of accuracy, soldiers were deployed in long lines (thus line infantry) to fire at the opposing forces. Precise aim was thus not necessary to hit an opponent. Muskets were used for comparatively rapid, imprecisely aimed volley fire, and the average soldier could be easily trained to use them.


title: Rifle

text: In the territory of Kentucky, one of the most successful early rifles, the long rifle, was developed over the course of the 18th century. Compared to the more common Brown Bess, they had a tighter bore with no space between bullet and barrel, and still used balls instead of conical bullets. The balls the long rifle used were smaller, allowing the production of more rounds for a given amount of lead. These rifles also had longer barrels, allowing more accuracy, which were rifled with a helical groove. These first started appearing sometime before 1740, one early example being made by Jacob Dickert, a German immigrant. By 1750 there were a number of such manufacturers in the area. The longer barrel was a departure by local gunsmiths from their German roots, allowing bullets to achieve a higher speed (as the burning gunpowder was contained longer) before emerging from the barrel.


title: Rifle

text: The rifle was used for precise shooting, aiming, and firing at individual targets, instead of the musket's use for imprecise fire.


title: Rifle

text: By the time of the American Revolutionary War, these rifles were commonly used by frontiersmen, and Congress authorized the establishment of ten companies of riflemen. One of the most critical units was Morgan's Riflemen, led by Daniel Morgan. This sharpshooting unit eventually proved itself integral to the Battle of Saratoga, and in the southern states where General Morgan commanded as well. Taking advantage of the rifle's improved accuracy, Morgan's sharpshooters picked off cannoneers and officers, reducing the impact of enemy artillery. This kind of advantage was considered pivotal in many battles, such as the battles of Cowpens, Saratoga, and King's Mountain.


title: Rifle

text: Later during the Napoleonic Wars, the British 95th Regiment (Green Jackets) and 60th Regiment, (Royal American), as well as sharpshooters and riflemen during the War of 1812, used the rifle to great effect during skirmishing. Because of a slower loading time than a musket, they were not adopted by the whole army. Since rifles were used by sharpshooters who did not routinely fire over other men's shoulders, long length was not required to avoid the forward line. A shorter length made a handier weapon in which tight-fitting balls did not have to be rammed so far down the barrel.


title: Rifle

text: The invention of the minie balls in the 1840s solved the slow loading problem, and in the 1850s and 1860s rifles quickly replaced muskets on the battlefield. Many rifles, often referred to as rifled muskets, were very similar to the muskets they replaced, but the military also experimented with other designs. Breech-loading weapons proved to have a much faster rate of fire than muzzleloaders, causing military forces to abandon muzzle loaders in favor of breech-loading designs in the late 1860s. In the later part of the 19th century, rifles were generally single-shot, breech-loading guns, designed for aimed, discretionary fire by individual soldiers. Then, as now, rifles had a stock, either fixed or folding, to be braced against the shoulder when firing.


title: Rifle

text: The adoption of cartridges and breech-loading in the 19th century was concurrent with the general adoption of rifles. In the early part of the 20th century, soldiers were trained to shoot accurately over long ranges with high-powered cartridges. World War I Lee–Enfield rifles (among others) were equipped with long-range 'volley sights' for massed firing at ranges of up to . Individual shots were unlikely to hit, but a platoon firing repeatedly could produce a 'beaten ground' effect similar to light artillery or machine guns.


title: Rifle

text: Currently, rifles are the most common firearm in general use for hunting (with the exception of bird hunting, where shotguns are favored). Rifles derived from military designs have long been popular with civilian shooters.


title: Rifle

text: During the Napoleonic Wars the British army created several experimental units known as "Rifles", armed with the Baker rifle. These Rifle Regiments were deployed as skirmishers during the Peninsular war in Spain and Portugal, and were more effective than skirmishers armed with muskets due to their accuracy and long range.


title: Rifle

text: Gradually, rifles appeared with cylindrical barrels cut with helical grooves, the surfaces between the grooves being "lands". The innovation was shortly followed by the mass adoption of breech-loading weapons, as it was not practical to push an overbore bullet down through a rifled barrel. The dirt and grime from prior shots were pushed down ahead of a tight bullet or ball (which may have been a looser fit in the clean barrel before the first shot), and loading was far more difficult, as the lead had to be deformed to go down in the first place, reducing the accuracy due to deformation. Several systems were tried to deal with the problem, usually by resorting to an under-bore bullet that expanded upon firing.


title: Rifle

text: The original muzzle-loading rifle, with a closely fitting ball to take the rifling grooves, was loaded with difficulty, particularly when foul, and for this reason was not generally used for military purposes. With the advent of rifling the bullet itself did not initially change but was wrapped in a greased, cloth patch to grip the rifling grooves.


title: Rifle

text: The first half of the 19th century saw a distinct change in the shape and function of the bullet. In 1826 Delvigne, a French infantry officer, invented a breech with abrupt shoulders on which a spherical bullet was rammed down until it caught the rifling grooves. Delvigne's method, however, deformed the bullet and was inaccurate.


title: Rifle

text: Soon after, the Carabine à tige was invented by Louis-Etienne de Thouvenin, which had a stem at the bottom of the barrel that would deform and expand the base of the bullet when rammed, therefore enabling accurate contact with the rifling. However, the area around the stem clogged and got dirty easily.


title: Rifle

text: One of the most famous was the Minié system, invented by French Army Captain Claude-Étienne Minié, which relied on a conical bullet (known as a Minié ball) with a hollow skirt at the base of the bullet. When fired, the skirt would expand from the pressure of the exploding charge and grip the rifling as the round was fired. The better seal gave more power, as less gas escaped past the bullet. Also, for the same bore (caliber) diameter a long bullet was heavier than a round ball. The extra grip also spun the bullet more consistently, which increased the range from about 50 yards for a smoothbore musket to about 300 yards for a rifle using the Minié system. The expanding skirt of the Minié ball also solved the problem that earlier tight-fitting bullets were difficult to load as black powder residue fouled the inside of the barrel. The Minié system allowed conical bullets to be loaded into rifles just as quickly as round balls in smooth bores, which allowed rifle muskets to replace muskets on the battlefield. Minié system rifles, notably the U.S. Springfield and the British Enfield of the early 1860s featured prominently in the U.S. Civil War, due to their enhanced power and accuracy.


title: Rifle

text: Over the 19th century, bullet design also evolved, the bullets becoming gradually smaller and lighter. By 1910 the standard blunt-nosed bullet had been replaced by the pointed, 'spitzer' bullet, an innovation that increased range and penetration. Cartridge design evolved from simple paper tubes containing black powder and shot, to sealed brass cases with integral primers for ignition, and black powder was replaced by cordite, and then other nitro-cellulose-based smokeless powder mixtures, propelling bullets to higher velocities than before.


title: Rifle

text: The increased velocity meant that new problems arrived, and so bullets went from being soft lead to harder lead, then to copper-jacketed, in order to better engage the spiral grooves without "stripping" them in the same way that a screw or bolt thread would be stripped if subjected to extreme forces.


title: Rifle

text: From 1836, breech-loading rifles were introduced with the German Dreyse Needle gun, followed by the French Tabatière in 1857, and the British Calisher and Terry carbine made in Birmingham and later in 1864 and the better known British Snider–Enfield. Primitive chamber-locking mechanisms were soon replaced by bolt-action mechanisms, exemplified by the Chassepot in 1866. Breech-loading was to have a major impact on warfare, as breech-loading rifles can be fired at a rate many times higher than muzzle-loaded rifles and significantly can be loaded from a prone rather than standing position. Firing prone (i.e., lying down) is more accurate than firing from a standing position, and a prone rifleman presents a much smaller target than a standing soldier. The higher accuracy and range, combined with reduced vulnerability generally benefited the defense while making the traditional battle between lines of standing and volleying infantrymen obsolete.


title: Rifle

text: Revolving rifles were an attempt to increase the rate of fire of rifles by combining them with the revolving firing mechanism that had been developed earlier for revolving pistols. Colt began experimenting with revolving rifles in the early 19th century, and other manufacturers like Remington later experimented with them as well. The Colt Revolving Rifle Model 1855 was an early repeating rifle and the first one to be used by the U.S. Government and saw some limited action during the American Civil War. Revolvers, both rifles and pistols, tend to spray fragments of metal from the front of the cylinder.


title: Rifle

text: The Winchester repeating rifle was invented in 1866. The firer pulled on a lever to reload the rifle with a stored cartridge.


title: Rifle

text: An important area of development was the way that cartridges were stored and used in the weapon. The Spencer repeating rifle was a breech-loading manually operated lever-action rifle that was adopted by the United States. Over 20,000 were used during the American Civil War. It was the first adoption of a removable magazine-fed infantry rifle. The design was completed by Christopher Spencer in 1860. It used copper rimfire cartridges stored in a removable seven-round tube magazine, enabling the rounds to be fired one after another. When the magazine was empty, it could be exchanged for another.


title: Rifle

text: In the Russo-Japanese War of 1904–1905, military observers from Europe and the United States witnessed a major conflict fought with high velocity bolt-action rifles firing smokeless powder. The Battle of Mukden fought in 1905 consisted of nearly 343,000 Russian troops against over 281,000 Japanese troops. The Russian Mosin–Nagant Model 1891 in 7.62mm was pitted against the Japanese Arisaka Type 30 bolt-action rifle in 6.5mm; both had velocities well over the 19th-century black powder velocities of under 2,000 feet per second (610 m/s).


title: Rifle

text: Until the late 19th century rifles tended to be very long, some long rifles reaching approximately 2 m (6 ft) in length to maximize accuracy, making early rifles impractical for use by cavalry. However, following the advent of more powerful smokeless powder, a shorter barrel did not impair accuracy as much. As a result, cavalry saw limited, but noteworthy, usage in 20th-century conflicts.


title: Rifle

text: The advent of the massed, rapid firepower of the machine gun, submachine gun and rifled artillery was so quick as to outstrip the development of any way to attack a trench defended by riflemen and machine gunners. The carnage of World War I was perhaps the greatest vindication and vilification of the rifle as a military weapon.


title: Rifle

text: The M1 Garand was a semi-automatic rapid-fire rifle developed for modern warfare use in World War II.


title: Rifle

text: During and after World War II it became accepted that most infantry engagements occurred at ranges of less than 300 m; the range and power of the large full-powered rifle cartridges were "overkill", requiring weapons heavier than otherwise necessary. This led to Germany's development of the 7.92×33mm "Kurz" (short) round, the MKb-42, and ultimately, the assault rifle. Today, an infantryman's rifle is optimized for ranges of 300 m or less, and soldiers are trained to deliver individual rounds or bursts of fire within these distances. Typically, the application of accurate, long-range fire is the domain of the marksman and the sniper in warfare, and of enthusiastic target shooters in peacetime. The modern marksman rifle and sniper rifle are usually capable of accuracy better than 0.3 mrad at 100 yards (1 arcminute).


title: Rifle

text: The Grizzly is a 3D printed .22-caliber rifle created around August 2013. It was created using a Stratasys Dimension 1200es printer. It was created by a Canadian only known by the pseudonym "Matthew" who told The Verge that he was in his late 20s, and his main job was making tools for the construction industry.


title: Rifle

text: The original Grizzly fired a single shot before breaking. Grizzly 2.0 fired fourteen bullets before getting damaged due to the strain.


title: Rifle

text: In October 2020, another 3D-printed 9mm rifle known as the "FGC-9mm" was created. It is reported that it can be made in 2 weeks with $500 of tools. A second model was later made in April 2021.


title: Rifle

text: A youth rifle is a rifle designed or modified for fitting children or other small-framed shooters. A youth rifle is often a single-shot .22 caliber rifle, or a bolt-action rifle, although some youth rifles are semi-automatic. They are usually very light, with a greatly shortened length of pull, which is necessary to accommodate children. Youth stocks are available for many popular rifles, such as the Ruger 10/22, a semi-automatic .22 LR rifle, allowing a youth rifle to be made from a standard rifle by simply changing the stock. The typical ages of shooters for such rifles vary from about age 5+.


title: Rifle

text: Some early rifled firearms had barrels with a twisted polygonal bore. The Whitworth rifle was the first such type designed to spin the round for accuracy. Bullets for these guns were made to match the shape of the bore so the bullet would grip the rifle bore and take a spin that way. These were generally large caliber weapons, and the ammunition still did not fit tightly in the barrel. Many different shapes and degrees of spiraling were used in experimental designs. One widely produced example was the Metford rifling in the Pattern 1888 Lee–Metford service rifle. Although uncommon, polygonal rifling is still used in some weapons today, one example being the Glock line of pistols (which fire standard bullets). Many of the early designs were prone to dangerous backfiring, which could lead to the destruction of the weapon and serious injury to the person firing it.


title: Rifle

text: As the bullet enters the barrel, it inserts itself into the rifling, a process that gradually wears down the barrel, and also causes the barrel to heat up more rapidly. Therefore, some machine guns are equipped with quick-change barrels that can be swapped every few thousand rounds, or in earlier designs, were water-cooled. Unlike older carbon steel barrels, which were limited to around 1,000 shots before the extreme heat caused accuracy to fade, modern stainless steel barrels for target rifles are much more resistant to wear, allowing many thousands of rounds to be fired before accuracy drops. (Many shotguns and small arms have chrome-lined barrels to reduce wear and enhance corrosion resistance. This is rare on rifles designed for extreme accuracy, as the plating process is difficult and liable to reduce the effect of the rifling.) Modern ammunition has a hardened lead core with a softer outer cladding or jacket, typically of an alloy of copper and nickel – cupro-nickel. Some ammunition is coated with molybdenum disulfide to further reduce internal friction – the so-called 'moly-coated' bullet.


title: Rifle

text: Rifles were initially single-shot, muzzle-loading weapons. During the 18th century, breech-loading weapons were designed, which allowed the rifleman to reload while under cover, but defects in manufacturing and the difficulty in forming a reliable gas-tight seal prevented widespread adoption. During the 19th century, multi-shot repeating rifles using lever, pump or linear bolt actions became standard, further increasing the rate of fire and minimizing the fuss involved in loading a firearm. The problem of proper seal creation had been solved with the use of brass cartridge cases, which expanded in an elastic fashion at the point of firing and effectively sealed the breech while the pressure remained high, then relaxed back enough to allow for easy removal. By the end of the 19th century, the leading bolt-action design was that of Paul Mauser, whose action—wedded to a reliable design possessing a five-shot magazine—became a world standard through two world wars and beyond. The Mauser rifle was paralleled by Britain's ten-shot Lee–Enfield and America's 1903 Springfield Rifle models. The American M1903 closely copied Mauser's original design.


title: Rifle

text: Barrel rifling dramatically increased the range and accuracy of the musket. Indeed, throughout its development, the rifle's history has been marked by increases in range and accuracy. From the Minié rifle and beyond, the rifle has become ever more potent at long-range strikes.


title: Rifle

text: In recent decades, large-caliber anti-materiel rifles, typically firing between 12.7 mm and 20 mm caliber cartridges, have been developed. The US Barrett M82A1 is probably the best-known such rifle. A second example is the AX50 by Accuracy International. These weapons are typically used to strike critical, vulnerable targets such as computerized command and control vehicles, radio trucks, radar antennae, vehicle engine blocks and the jet engines of enemy aircraft. Anti-materiel rifles can be used against human targets, but the much higher weight of rifle and ammunition, and the massive recoil and muzzle blast, usually make them less than practical for such use. The Barrett M82 is designed with a maximum effective range of , although it has a confirmed kill distance of in Afghanistan during Operation Anaconda in 2002. The record for the longest confirmed kill shot stands at , set by an unnamed soldier with Canada's elite special operations unit Joint Task Force 2 using a McMillan TAC-50 sniper rifle.


title: Rifle

text: Bullets leaving a rifled barrel can spin at a rotational speed of over 100,000 revolutions per minute (rpm) (or over about 1.67 kilohertz, since 1 RPM = 1/60 Hz). The rotational speed depends both on the muzzle velocity of the bullet and the pitch of the rifling. Excessive rotational speed can exceed the bullet's designed limits and the inadequate centripetal force will fail to keep the bullet from disintegrating in a radial fashion. The rotational speed of the bullet can be calculated by using the formula below.


title: Rifle

text: Using metric units, the formula divides the number of millimeters in a meter (1000) by the barrel twist in millimeters (the length of travel along the barrel per full rotation). This number is then multiplied by the muzzle velocity in meters per second (m/s) and the number of seconds in a minute (60).


title: Rifle

text: Using imperial units, the formula divides the number of inches in a foot (12) by the rate of twist that the barrel has. This number is multiplied by the muzzle velocity (MV) and the number of seconds in a minute (60). For example, a bullet with a muzzle velocity of leaving a barrel that twists once per foot (1/12") would rotate at 180,000rpm.


title: Rifle

text: For example, using a barrel that has a twist rate of 1 turn in 8" with a muzzle velocity of 3000 ft/s:


title: Rifle

text: Rifles may be chambered in a variety of calibers (bullet or barrel diameters), from as low as 4.4 mm (.17 inch) varmint calibers to as high as 20 mm (.80 caliber) in the case of the largest anti-tank rifles. The term caliber essentially refers to the width of the bullet fired through a rifle's barrel. Armies have consistently attempted to find and procure the most lethal and accurate caliber for their firearms.


title: Rifle

text: The standard calibers used by the world's militaries tend to follow worldwide trends. These trends have significantly changed during the centuries of firearm design and re-design. Muskets were normally chambered for large calibers, such as .50 or .59 (12.7 mm or 15 mm), with the theory that these large bullets caused the most damage.


title: Rifle

text: During World War I and II, most rifles were chambered in .30 caliber (7.62 mm), a combination of power and speed. Examples would be the .303 British Lee–Enfield, the American M1903 .30-06, and the German 8mm Mauser K98.


title: Rifle

text: Detailed study of infantry combat during and after World War II revealed that most small-arms engagements occurred within 100 meters, meaning that the power and range of the traditional .30-caliber weapons (designed for engagements at 500 meters and beyond) were essentially wasted. The single greatest predictor of an individual soldier's combat effectiveness was the number of rounds he fired. Weapons designers and strategists realized that service rifles firing smaller-caliber projectiles would allow troops to carry far more ammunition for the same weight. The lower recoil and more generous magazine capacities of small-caliber weapons also allow troops a much greater volume of fire, compared to historical battle rifles. Smaller, faster traveling, less stable projectiles have also demonstrated greater terminal ballistics and therein, a greater lethality than traditional .30-caliber rounds. Most modern service rifles fire a projectile of approximately 5.56 mm. Examples of firearms in this range are the American 5.56 mm M16 and the Russian 5.45×39mm AK-74.


title: Wave–particle duality

text: Wave–particle duality is the concept in quantum mechanics that every particle or quantum entity may be described as either a particle or a wave. It expresses the inability of the classical concepts "particle" or "wave" to fully describe the behaviour of quantum-scale objects. As Albert Einstein wrote:


title: Wave–particle duality

text: Through the work of Max Planck, Albert Einstein, Louis de Broglie, Arthur Compton, Niels Bohr, Erwin Schrödinger and many others, current scientific theory holds that all particles exhibit a wave nature and vice versa. This phenomenon has been verified not only for elementary particles, but also for compound particles like atoms and even molecules. For macroscopic particles, because of their extremely short wavelengths, wave properties usually cannot be detected.


title: Wave–particle duality

text: Although the use of the wave–particle duality has worked well in physics, the meaning or interpretation has not been satisfactorily resolved; see interpretations of quantum mechanics.


title: Wave–particle duality

text: Bohr regarded the "duality paradox" as a fundamental or metaphysical fact of nature. A given kind of quantum object will exhibit sometimes wave, sometimes particle, character, in respectively different physical settings. He saw such duality as one aspect of the concept of complementarity. Bohr regarded renunciation of the cause-effect relation, or complementarity, of the space-time picture, as essential to the quantum mechanical account.


title: Wave–particle duality

text: Werner Heisenberg considered the question further. He saw the duality as present for all quantic entities, but not quite in the usual quantum mechanical account considered by Bohr. He saw it in what is called second quantization, which generates an entirely new concept of fields that exist in ordinary space-time, causality still being visualizable. Classical field values (e.g. the electric and magnetic field strengths of Maxwell) are replaced by an entirely new kind of field value, as considered in quantum field theory. Turning the reasoning around, ordinary quantum mechanics can be deduced as a specialized consequence of quantum field theory.


title: Wave–particle duality

text: Democritus (5th century BC) argued that all things in the universe, including light, are composed of indivisible sub-components. Euclid (4th–3rd century BC) gives treatises on light propagation, states the principle of shortest trajectory of light, including multiple reflections on mirrors, including spherical, while Plutarch (1st–2nd century AD) describes multiple reflections on spherical mirrors discussing the creation of larger or smaller images, real or imaginary, including the case of chirality of the images. At the beginning of the 11th century, the Arabic scientist Ibn al-Haytham wrote the first comprehensive "Book of Optics" describing reflection, refraction, and the operation of a pinhole lens via rays of light traveling from the point of emission to the eye. He asserted that these rays were composed of particles of light. In 1630, René Descartes popularized the opposing wave description in his treatise on light, The World, showing that the behaviour of light could be re-created by modeling wave-like disturbances in a universal medium i.e. luminiferous aether. Beginning in 1670 and progressing over three decades, Isaac Newton developed and championed his corpuscular theory, arguing that the perfectly straight lines of reflection demonstrated light's particle nature, only particles could travel in such straight lines. He explained refraction by positing that particles of light accelerated laterally upon entering a denser medium. Around the same time, Newton's contemporaries Robert Hooke and Christiaan Huygens, and later Augustin-Jean Fresnel, mathematically refined the wave viewpoint, showing that if light traveled at different speeds in different media, refraction could be easily explained as the medium-dependent propagation of light waves. The resulting Huygens–Fresnel principle was extremely successful at reproducing light's behaviour and was subsequently supported by Thomas Young's discovery of wave interference of light by his double-slit experiment in 1801. The wave view did not immediately displace the ray and particle view, but began to dominate scientific thinking about light in the mid 19th century, since it could explain polarization phenomena that the alternatives could not.


title: Wave–particle duality

text: James Clerk Maxwell discovered that he could apply his previously discovered Maxwell's equations, along with a slight modification to describe self-propagating waves of oscillating electric and magnetic fields. It quickly became apparent that visible light, ultraviolet light, and infrared light were all electromagnetic waves of differing frequency.


title: Wave–particle duality

text: In 1901, Max Planck published an analysis that succeeded in reproducing the observed spectrum of light emitted by a glowing object. To accomplish this, Planck had to make a mathematical assumption of quantized energy of the oscillators, i.e. atoms of the black body that emit radiation. Einstein later proposed that electromagnetic radiation itself is quantized, not the energy of radiating atoms.


title: Wave–particle duality

text: Black-body radiation, the emission of electromagnetic energy due to an object's heat, could not be explained from classical arguments alone. The equipartition theorem of classical mechanics, the basis of all classical thermodynamic theories, stated that an object's energy is partitioned equally among the object's vibrational modes. But applying the same reasoning to the electromagnetic emission of such a thermal object was not so successful. That thermal objects emit light had been long known. Since light was known to be waves of electromagnetism, physicists hoped to describe this emission via classical laws. This became known as the black body problem. Since the equipartition theorem worked so well in describing the vibrational modes of the thermal object itself, it was natural to assume that it would perform equally well in describing the radiative emission of such objects. But a problem quickly arose if each mode received an equal partition of energy, the short wavelength modes would consume all the energy. This became clear when plotting the Rayleigh–Jeans law, which, while correctly predicting the intensity of long wavelength emissions, predicted infinite total energy as the intensity diverges to infinity for short wavelengths. This became known as the ultraviolet catastrophe.


title: Wave–particle duality

text: In 1900, Max Planck hypothesized that the frequency of light emitted by the black body depended on the frequency of the oscillator that emitted it, and the energy of these oscillators increased linearly with frequency (according "E" = "hf" where "h" is Planck's constant and "f" is the frequency). This was not an unsound proposal considering that macroscopic oscillators operate similarly when studying five simple harmonic oscillators of equal amplitude but different frequency, the oscillator with the highest frequency possesses the highest energy (though this relationship is not linear like Planck's). By demanding that high-frequency light must be emitted by an oscillator of equal frequency, and further requiring that this oscillator occupy higher energy than one of a lesser frequency, Planck avoided any catastrophe, giving an equal partition to high-frequency oscillators produced successively fewer oscillators and less emitted light. And as in the Maxwell–Boltzmann distribution, the low-frequency, low-energy oscillators were suppressed by the onslaught of thermal jiggling from higher energy oscillators, which necessarily increased their energy and frequency.


title: Wave–particle duality

text: The most revolutionary aspect of Planck's treatment of the black body is that it inherently relies on an integer number of oscillators in thermal equilibrium with the electromagnetic field. These oscillators give their entire energy to the electromagnetic field, creating a quantum of light, as often as they are excited by the electromagnetic field, absorbing a quantum of light and beginning to oscillate at the corresponding frequency. Planck had intentionally created an atomic theory of the black body, but had unintentionally generated an atomic theory of light, where the black body never generates quanta of light at a given frequency with an energy less than "hf". However, once realizing that he had quantized the electromagnetic field, he denounced particles of light as a limitation of his approximation, not a property of reality.


title: Wave–particle duality

text: While Planck had solved the ultraviolet catastrophe by using atoms and a quantized electromagnetic field, most contemporary physicists agreed that Planck's "light quanta" represented only flaws in his model. A more-complete derivation of black-body radiation would yield a fully continuous and "wave-like" electromagnetic field with no quantization. However, in 1905 Albert Einstein took Planck's black body model to produce his solution to another outstanding problem of the day: the photoelectric effect, wherein electrons are emitted from atoms when they absorb energy from light. Since their existence was theorized eight years previously, phenomena had been studied with the electron model in mind in physics laboratories worldwide.


title: Wave–particle duality

text: In 1902, Philipp Lenard discovered that the energy of these ejected electrons did not depend on the intensity of the incoming light, but instead on its frequency. So if one shines a little low-frequency light upon a metal, a few low energy electrons are ejected. If one now shines a very intense beam of low-frequency light upon the same metal, a whole slew of electrons are ejected; however they possess the same low energy, there are merely more of them. The more light there is, the more electrons are ejected. Whereas in order to get high energy electrons, one must illuminate the metal with high-frequency light. Like blackbody radiation, this was at odds with a theory invoking continuous transfer of energy between radiation and matter. However, it can still be explained using a fully classical description of light, as long as matter is quantum mechanical in nature.


title: Wave–particle duality

text: If one used Planck's energy quanta, and demanded that electromagnetic radiation at a given frequency could only transfer energy to matter in integer multiples of an energy quantum "hf", then the photoelectric effect could be explained very simply. Low-frequency light only ejects low-energy electrons because each electron is excited by the absorption of a single photon. Increasing the intensity of the low-frequency light (increasing the number of photons) only increases the number of excited electrons, not their energy, because the energy of each photon remains low. Only by increasing the frequency of the light, and thus increasing the energy of the photons, can one eject electrons with higher energy. Thus, using Planck's constant "h" to determine the energy of the photons based upon their frequency, the energy of ejected electrons should also increase linearly with frequency, the gradient of the line being Planck's constant. These results were not confirmed until 1915, when Robert Andrews Millikan produced experimental results in perfect accord with Einstein's predictions.


title: Wave–particle duality

text: While energy of ejected electrons reflected Planck's constant, the existence of photons was not explicitly proven until the discovery of the photon antibunching effect. This refers to the observation that once a single emitter (an atom, molecule, solid state emitter, etc.) radiates a detectable light signal, it cannot immediately release a second signal until after the emitter has been re-excited. This leads to a statistically quantifiable time delay between light emissions, so detection of multiple signals becomes increasingly unlikely as the observation time dips under the excited-state lifetime of the emitter. The effect can be demonstrated in an undergraduate-level lab.


title: Wave–particle duality

text: This phenomenon could only be explained via photons. Einstein's "light quanta" would not be called photons until 1925, but even in 1905 they represented the quintessential example of wave–particle duality. Electromagnetic radiation propagates following linear wave equations, but can only be emitted or absorbed as discrete elements, thus acting as a wave and a particle simultaneously.


title: Wave–particle duality

text: In 1905, Albert Einstein provided an explanation of the photoelectric effect, an experiment that the wave theory of light failed to explain. He did so by postulating the existence of photons, quanta of light energy with particulate qualities.


title: Wave–particle duality

text: In the photoelectric effect, it was observed that shining a light on certain metals would lead to an electric current in a circuit. Presumably, the light was knocking electrons out of the metal, causing current to flow. However, using the case of potassium as an example, it was also observed that while a dim blue light was enough to cause a current, even the strongest, brightest red light available with the technology of the time caused no current at all. According to the classical theory of light and matter, the strength or amplitude of a light wave was in proportion to its brightness: a bright light should have been easily strong enough to create a large current. Yet, oddly, this was not so.


title: Wave–particle duality

text: Einstein explained this enigma by postulating that electrons can receive energy from an electromagnetic field only in discrete units (quanta or photons): an amount of energy "E" that was related to the frequency "f" of the light by


title: Wave–particle duality

text: where "h" is Planck's constant (6.626 × 10 Js). Only photons of a high enough frequency (above a certain "threshold" value) could knock an electron free. For example, photons of blue light had sufficient energy to free an electron from the metal, but photons of red light did not. One photon of light above the threshold frequency could release only one electron; the higher the frequency of a photon, the higher the kinetic energy of the emitted electron, but no amount of light below the threshold frequency could release an electron. To violate this law would require extremely high-intensity lasers that had not yet been invented. Intensity-dependent phenomena have now been studied in detail with such lasers.


title: Wave–particle duality

text: Einstein was awarded the Nobel Prize in Physics in 1921 for his discovery of the law of the photoelectric effect.


title: Wave–particle duality

text: In 1924, Louis-Victor de Broglie formulated the de Broglie hypothesis, claiming that all matter has a wave-like nature. He related wavelength and momentum:


title: Wave–particle duality

text: This is a generalization of Einstein's equation above, since the momentum of a photon is given by "p" = formula_3 and the wavelength (in a vacuum) by "λ" = formula_4, where "c" is the speed of light in vacuum.


title: Wave–particle duality

text: De Broglie's formula was confirmed three years later for electrons with the observation of electron diffraction in two independent experiments. At the University of Aberdeen, George Paget Thomson passed a beam of electrons through a thin metal film and observed the predicted interference patterns. At Bell Labs, Clinton Joseph Davisson and Lester Halbert Germer guided the electron beam through a crystalline grid in their experiment popularly known as Davisson–Germer experiment.


title: Wave–particle duality

text: De Broglie was awarded the Nobel Prize for Physics in 1929 for his hypothesis. Thomson and Davisson shared the Nobel Prize for Physics in 1937 for their experimental work.


title: Wave–particle duality

text: In his work on formulating quantum mechanics, Werner Heisenberg postulated his uncertainty principle, which states:


title: Wave–particle duality

text: Heisenberg originally explained this as a consequence of the process of measuring: Measuring position accurately would disturb momentum and vice versa, offering an example (the "gamma-ray microscope") that depended crucially on the de Broglie hypothesis. The thought is now, however, that this only partly explains the phenomenon, but that the uncertainty also exists in the particle itself, even before the measurement is made.


title: Wave–particle duality

text: In fact, the modern explanation of the uncertainty principle, extending the Copenhagen interpretation first put forward by Bohr and Heisenberg, depends even more centrally on the wave nature of a particle. Just as it is nonsensical to discuss the precise location of a wave on a string, particles do not have perfectly precise positions; likewise, just as it is nonsensical to discuss the wavelength of a "pulse" wave traveling down a string, particles do not have perfectly precise momenta that correspond to the inverse of wavelength. Moreover, when position is relatively well defined, the wave is pulse-like and has a very ill-defined wavelength, and thus momentum. And conversely, when momentum, and thus wavelength, is relatively well defined, the wave looks long and sinusoidal, and therefore it has a very ill-defined position.


title: Wave–particle duality

text: De Broglie himself had proposed a pilot wave construct to explain the observed wave–particle duality. In this view, each particle has a well-defined position and momentum, but is guided by a wave function derived from Schrödinger's equation. The pilot wave theory was initially rejected because it generated non-local effects when applied to systems involving more than one particle. Non-locality, however, soon became established as an integral feature of quantum theory and David Bohm extended de Broglie's model to explicitly include it.


title: Wave–particle duality

text: In the resulting representation, also called the de Broglie–Bohm theory or Bohmian mechanics, the wave–particle duality vanishes, and explains the wave behaviour as a scattering with wave appearance, because the particle's motion is subject to a guiding equation or quantum potential.


title: Wave–particle duality

text: The best illustration of the "pilot-wave model" was given by Couder's 2010 "walking droplets" experiments, demonstrating the pilot-wave behaviour in a macroscopic mechanical analog.


title: Wave–particle duality

text: Since the demonstrations of wave-like properties in photons and electrons, similar experiments have been conducted with neutrons and protons. Among the most famous experiments are those of Estermann and Otto Stern in 1929.


title: Wave–particle duality

text: Authors of similar recent experiments with atoms and molecules, described below, claim that these larger particles also act like waves.


title: Wave–particle duality

text: A dramatic series of experiments emphasizing the action of gravity in relation to wave–particle duality was conducted in the 1970s using the neutron interferometer. Neutrons, one of the components of the atomic nucleus, provide much of the mass of a nucleus and thus of ordinary matter. In the neutron interferometer, they act as quantum-mechanical waves directly subject to the force of gravity. While the results were not surprising since gravity was known to act on everything, including light (see tests of general relativity and the Pound–Rebka falling photon experiment), the self-interference of the quantum mechanical wave of a massive fermion in a gravitational field had never been experimentally confirmed before.


title: Wave–particle duality

text: In 1999, the diffraction of C fullerenes by researchers from the University of Vienna was reported. Fullerenes are comparatively large and massive objects, having an atomic mass of about 720 u. The de Broglie wavelength of the incident beam was about 2.5 pm, whereas the diameter of the molecule is about 1 nm, about 400 times larger. In 2012, these far-field diffraction experiments could be extended to phthalocyanine molecules and their heavier derivatives, which are composed of 58 and 114 atoms respectively. In these experiments the build-up of such interference patterns could be recorded in real time and with single molecule sensitivity.


title: Wave–particle duality

text: In 2003, the Vienna group also demonstrated the wave nature of tetraphenylporphyrin—a flat biodye with an extension of about 2 nm and a mass of 614 u. For this demonstration they employed a near-field Talbot Lau interferometer. In the same interferometer they also found interference fringes for CF, a fluorinated buckyball with a mass of about 1600 u, composed of 108 atoms. Large molecules are already so complex that they give experimental access to some aspects of the quantum-classical interface, i.e., to certain decoherence mechanisms. In 2011, the interference of molecules as heavy as 6910 u could be demonstrated in a Kapitza–Dirac–Talbot–Lau interferometer. In 2013, the interference of molecules beyond 10,000 u has been demonstrated.


title: Wave–particle duality

text: Whether objects heavier than the Planck mass (about the weight of a large bacterium) have a de Broglie wavelength is theoretically unclear and experimentally unreachable; above the Planck mass a particle's Compton wavelength would be smaller than the Planck length and its own Schwarzschild radius, a scale at which current theories of physics may break down or need to be replaced by more general ones.


title: Wave–particle duality

text: Couder, Fort, "et al." showed that macroscopic oil droplets on a vibrating fluid bath can be used as an analogue model of wave–particle duality; a localized droplet creates periodical wave field around itself. Resonant interaction between the droplet and its own wave field exhibits behaviour analogous to quantum particles: interference in double-slit experiment, unpredictable tunneling (depending in complicated way on practically hidden state of field), orbit quantization (that particle has to 'find a resonance' with field perturbations it creates—after one orbit, its internal phase has to return to the initial state) and Zeeman effect. Note that other single and double slit experiments have shown that wall-droplet interactions rather than diffraction or interference of the pilot wave may be responsible for the observed hydrodynamic patterns, which are different from slit-induced interference patterns exhibited by quantum particles.


title: Wave–particle duality

text: Wave–particle duality is deeply embedded into the foundations of quantum mechanics. In the formalism of the theory, all the information about a particle is encoded in its wave function, a complex-valued function roughly analogous to the amplitude of a wave at each point in space. This function evolves according to Schrödinger equation. For particles with mass this equation has solutions that follow the form of the wave equation. Propagation of such waves leads to wave-like phenomena such as interference and diffraction. Particles without mass, like photons, have no solutions of the Schrödinger equation. Instead of a particle wave function that localizes mass in space, a photon wave function can be constructed from Einstein kinematics to localize energy in spatial coordinates.


title: Wave–particle duality

text: The particle-like behaviour is most evident due to phenomena associated with measurement in quantum mechanics. Upon measuring the location of the particle, the particle will be forced into a more localized state as given by the uncertainty principle. When viewed through this formalism, the measurement of the wave function will randomly lead to wave function collapse to a sharply peaked function at some location. For particles with mass, the likelihood of detecting the particle at any particular location is equal to the squared amplitude of the wave function there. The measurement will return a well-defined position, and is subject to Heisenberg's uncertainty principle.


title: Wave–particle duality

text: Following the development of quantum field theory the ambiguity disappeared. The field permits solutions that follow the wave equation, which are referred to as the wave functions. The term particle is used to label the irreducible representations of the Lorentz group that are permitted by the field. An interaction as in a Feynman diagram is accepted as a calculationally convenient approximation where the outgoing legs are known to be simplifications of the propagation and the internal lines are for some order in an expansion of the field interaction. Since the field is non-local and quantized, the phenomena that previously were thought of as paradoxes are explained. Within the limits of the wave–particle duality the quantum field theory gives the same results.


title: Wave–particle duality

text: There are two ways to visualize the wave-particle behaviour: by the standard model and by the de Broglie–Bohm theory.


title: Wave–particle duality

text: Below is an illustration of wave–particle duality as it relates to de Broglie's hypothesis and Heisenberg's Uncertainty principle, in terms of the position and momentum space wavefunctions for one spinless particle with mass in one dimension. These wavefunctions are Fourier transforms of each other.


title: Wave–particle duality

text: The more localized the position-space wavefunction, the more likely the particle is to be found with the position coordinates in that region, and correspondingly the momentum-space wavefunction is less localized so the possible momentum components the particle could have are more widespread.


title: Wave–particle duality

text: Conversely, the more localized the momentum-space wavefunction, the more likely the particle is to be found with those values of momentum components in that region, and correspondingly the less localized the position-space wavefunction, so the position coordinates the particle could occupy are more widespread.