Film

Mechanisms for producing artificially created, two-dimensional images in motion were demonstrated as early as the 1860s, with devices such as the zoetrope and the praxinoscope. These machines were outgrowths of simple optical devices (such as magic lanterns), and would display sequences of still pictures at sufficient speed for the images on the pictures to appear to be moving, a phenomenon called persistence of vision. Naturally, the images needed to be carefully designed to achieve the desired effect — and the underlying principle became the basis for the development of film animation.
A frame from Roundhay Garden Scene, the world's earliest surviving film, by Louis Le Prince, 1888
A frame from Roundhay Garden Scene, the world's earliest surviving film, by Louis Le Prince, 1888

With the development of celluloid film for still photography, it became possible to directly capture objects in motion in real time. Early versions of the technology sometimes required the viewer to look into a special device to see the pictures. By the 1880s, the development of the motion picture camera allowed the individual component images to be captured and stored on a single reel, and led quickly to the development of a motion picture projector to shine light through the processed and printed film and magnify these "moving picture shows" onto a screen for an entire audience. These reels, so exhibited, came to be known as "motion pictures." Early motion pictures were static shots that showed an event or action with no editing or other cinematic techniques.
A shot from Georges Méliès Le Voyage dans la Lune (A Trip to the Moon) (1902), an early narrative film.
A shot from Georges Méliès Le Voyage dans la Lune (A Trip to the Moon) (1902), an early narrative film.

Motion pictures were purely visual art up to the late 19th century, but these innovative silent films had gained a hold on the public imagination. Around the turn of the twentieth century, films began developing a narrative structure by stringing scenes together to tell narratives. The scenes were later broken up into multiple shots of varying sizes and angles. Other techniques such as camera movement were realized as effective ways to portray a story on film. Rather than leave the audience in silence, theater owners would hire a pianist or organist or a full orchestra to play music fitting the mood of the film at any given moment. By the early 1920s, most films came with a prepared list of sheet music for this purpose, with complete film scores being composed for major productions.

The rise of European cinema was interrupted by the breakout of World War I while the film industry in United States flourished with the rise of Hollywood. However in the 1920s, European filmmakers such as Sergei Eisenstein and F. W. Murnau, along with American innovator D. W. Griffith and the contributions of Charles Chaplin, Buster Keaton and others, continued to advance the medium. In the 1920s, new technology allowed filmmakers to attach to each film a soundtrack of speech, music and sound effects synchronized with the action on the screen. These sound films were initially distinguished by calling them "talking pictures", or talkies.

The next major step in the development of cinema was the introduction of color. While the addition of sound quickly eclipsed silent film and theater musicians, color was adopted more gradually. The public was relatively indifferent to color photography as opposed to black-and-white,[citation needed] but as color processes improved and became as affordable as black-and-white film, more and more movies were filmed in color after the end of World War II, as the industry in America came to view color as essential to attracting audiences in its competition with television, which remained a black-and-white medium until the mid-1960s. By the end of the 1960s, color had become the norm for film makers.

Since the decline of the studio system in the 1960s, the succeeding decades saw changes in the production and style of film. New Hollywood, French New Wave and the rise of film school educated independent filmmakers were all part of the changes the medium experienced in the latter half of the 20th century. Digital technology has been the driving force in change throughout the 1990s and into the 21st century.

Theory

Main article: Film theory

Film theory seeks to develop concise, systematic concepts that apply to the study of film as art. It was started by Ricciotto Canudo's The Birth of the Sixth Art. Formalist film theory, led by Rudolf Arnheim, Béla Balázs, and Siegfried Kracauer, emphasized how film differed from reality, and thus could be considered a valid fine art. André Bazin reacted against this theory by arguing that film's artistic essence lay in its ability to mechanically reproduce reality not in its differences from reality, and this gave rise to realist theory. More recent analysis spurred by Lacan's psychoanalysis and Ferdinand de Saussure's semiotics among other things has given rise to psychoanalytical film theory, structuralist film theory, feminist film theory and others.

Criticism

Main article: Film criticism

Abbas Kiarostami and Bernardo Bertolucci on the poster of "Exhibition of the Persian Maestro's Art work" held in Rome.
Abbas Kiarostami and Bernardo Bertolucci on the poster of "Exhibition of the Persian Maestro's Art work" held in Rome.

Film criticism is the analysis and evaluation of films. In general, these works can be divided into two categories: academic criticism by film scholars and journalistic film criticism that appears regularly in newspapers and other media.

Film critics working for newspapers, magazines, and broadcast media mainly review new releases. Normally they only see any given film once and have only a day or two to formulate opinions. Despite this, critics have an important impact on films, especially those of certain genres. Mass marketed action, horror, and comedy films tend not to be greatly affected by a critic's overall judgment of a film. The plot summary and description of a film that makes up the majority of any film review can still have an important impact on whether people decide to see a film. For prestige films such as most dramas, the influence of reviews is extremely important. Poor reviews will often doom a film to obscurity and financial loss.

The impact of a reviewer on a given film's box office performance is a matter of debate. Some claim that movie marketing is now so intense and well financed that reviewers cannot make an impact against it. However, the cataclysmic failure of some heavily-promoted movies which were harshly reviewed, as well as the unexpected success of critically praised independent movies indicates that extreme critical reactions can have considerable influence. Others note that positive film reviews have been shown to spark interest in little-known films. Conversely, there have been several films in which film companies have so little confidence that they refuse to give reviewers an advanced viewing to avoid widespread panning of the film. However, this usually backfires as reviewers are wise to the tactic and warn the public that the film may not be worth seeing and the films often do poorly as a result.

It is argued that journalist film critics should only be known as film reviewers, and true film critics are those who take a more academic approach to films. This line of work is more often known as film theory or film studies. These film critics attempt to come to understand how film and filming techniques work, and what effect they have on people. Rather than having their works published in newspapers or appear on television, their articles are published in scholarly journals, or sometimes in up-market magazines. They also tend to be affiliated with colleges or universities.

Industry

Main article: Film industry

The making and showing of motion pictures became a source of profit almost as soon as the process was invented. Upon seeing how successful their new invention, and its product, was in their native France, the Lumières quickly set about touring the Continent to exhibit the first films privately to royalty and publicly to the masses. In each country, they would normally add new, local scenes to their catalogue and, quickly enough, found local entrepreneurs in the various countries of Europe to buy their equipment and photograph, export, import and screen additional product commercially. The Oberammergau Passion Play of 1898 was the first commercial motion picture ever produced. Other pictures soon followed, and motion pictures became a separate industry that overshadowed the vaudeville world. Dedicated theaters and companies formed specifically to produce and distribute films, while motion picture actors became major celebrities and commanded huge fees for their performances. Already by 1917, Charlie Chaplin had a contract that called for an annual salary of one million dollars.

In the United States today, much of the film industry is centered around Hollywood. Other regional centers exist in many parts of the world, and the Indian film industry (primarily centered around "Bollywood")[citation needed] annually produces the largest number of films in the world. Whether the ten thousand-plus feature length films a year produced by the Valley pornographic film industry should qualify for this title is the source of some debate.[citation needed] Though the expense involved in making movies has led cinema production to concentrate under the auspices of movie studios, recent advances in affordable film making equipment have allowed independent film productions to flourish.

Profit is a key force in the industry, due to the costly and risky nature of filmmaking; many films have large cost overruns, a notorious example being Kevin Costner's Waterworld. Yet many filmmakers strive to create works of lasting social significance. The Academy Awards (also known as "the Oscars") are the most prominent film awards in the United States, providing recognition each year to films, ostensibly based on their artistic merits.

There is also a large industry for educational and instructional films made in lieu of or in addition to lectures and texts.

Production

Main article: Filmmaking

The nature of the film determines the size and type of crew required during filmmaking. Many Hollywood adventure films need computer generated imagery (CGI), created by dozens of 3D modellers, animators, rotoscopers and compositors. However, a low-budget, independent film may be made with a skeleton crew, often paid very little. Also, an open source film may be produced through open, collaborative processes. Filmmaking takes place all over the world using different technologies, styles of acting and genre, and is produced in a variety of economic contexts that range from state-sponsored documentary in China to profit-oriented movie making within the American studio system.

A typical Hollywood-style filmmaking Production cycle comprises five main stages:

1. Development
2. Pre-production
3. Production
4. Post-production
5. Distribution

This production cycle typically takes three years. The first year is taken up with development. The second year comprises preproduction and production. The third year, post-production and distribution.

Crew

Main article: Film crew

A film crew is a group of people hired by a film company, employed during the photography phase, for the purpose of producing a film or motion picture. Crew are distinguished from cast, the actors who appear in front of the camera or provide voices for characters in the film. The crew interacts with, but is also distinct from the production staff, consisting of producers, managers, company representatives, their assistants, and those whose primary responsibility falls in pre-production or post-production phases, such as writers and editors. Communication between production and crew generally passes through the director and his/her staff of assistants. Medium to large crews are generally divided into departments with well defined hierarchies, and standards for interaction and cooperation between the departments. Other than acting, the crew handles everything in the photography phase—props and costumes, shooting, sound, electrics, sets, and production special effects.

Independent

Main article: Independent film

The Lumière Brothers
The Lumière Brothers

Independent filmmaking often takes place outside of Hollywood, or other major studio systems. An independent film (or indie film) is a film initially produced without financing or distribution from a major movie studio. Creative, business, and technological reasons have all contributed to the growth of the indie film scene in the late 20th and early 21st century.

On the business side, the costs of big-budget studio films also leads to conservative choices in cast and crew. There is a trend in Hollywood towards co-financing (over two-thirds of the films put out by Warner Bros. in 2000 were joint ventures, up from 10% in 1987).[citation needed] A hopeful director is almost never given the opportunity to get a job on a big-budget study film unless he or she has significant industry experience in film or television. Also, the studios rarely produce films with unknown actors, particularly in lead roles.

Before the advent of digital alternatives, the cost of professional film equipment and stock was also a hurdle to being able to produce, direct, or star in a traditional studio film. The cost of 35 mm film is outpacing inflation: in 2002 alone, film negative costs were up 23%, according to Variety.[citation needed] Film requires expensive lighting and post-production facilities.

But the advent of consumer camcorders in 1985, and more importantly, the arrival of high-resolution digital video in the early 1990s, have lowered the technology barrier to movie production significantly. Both production and post-production costs have been significantly lowered; today, the hardware and software for post-production can be installed in a commodity-based personal computer. Technologies such as DVDs, FireWire connections and non-linear editing system pro-level software like Adobe Premiere Pro, Sony Vegas and Apple's Final Cut Pro, and consumer level software such as Apple's Final Cut Express and iMovie make movie-making relatively inexpensive.

Since the introduction of DV technology, the means of production have become more democratized. Filmmakers can conceivably shoot and edit a movie, create and edit the sound and music, and mix the final cut on a home computer. However, while the means of production may be democratized, financing, distribution, and marketing remain difficult to accomplish outside the traditional system. Most independent filmmakers rely on film festivals to get their films noticed and sold for distribution.

Open content film

Main article: Open content film

An open content film is much like an independent film, but it is produced through open collaborations; its source material is available under a license which is more permissive enough to allow other parties to create fan fiction or derivative works, than a traditional copyright. Like independent filmmaking, open source filmmaking takes place outside of Hollywood, or other major studio systems.

Fan film

Main article: Fan film

A fan film is a film or video inspired by a film, television program, comic book or a similar source, created by fans rather than by the source's copyright holders or creators. Fan filmmakers have traditionally been amateurs, but some of the more notable films have actually been produced by professional filmmakers as film school class projects or as demonstration reels. Fan films vary tremendously in length, from short faux-teaser trailers for non-existent motion pictures to rarer full-length motion pictures.

Animation

Main article: Animation

Animation is the technique in which each frame of a film is produced individually, whether generated as a computer graphic, or by photographing a drawn image, or by repeatedly making small changes to a model unit (see claymation and stop motion), and then photographing the result with a special animation camera. When the frames are strung together and the resulting film is viewed at a speed of 16 or more frames per second, there is an illusion of continuous movement (due to the persistence of vision). Generating such a film is very labour intensive and tedious, though the development of computer animation has greatly sped up the process.

File formats like GIF, QuickTime, Shockwave and Flash allow animation to be viewed on a computer or over the Internet.

Because animation is very time-consuming and often very expensive to produce, the majority of animation for TV and movies comes from professional animation studios. However, the field of independent animation has existed at least since the 1950s, with animation being produced by independent studios (and sometimes by a single person). Several independent animation producers have gone on to enter the professional animation industry.

Limited animation is a way of increasing production and decreasing costs of animation by using "short cuts" in the animation process. This method was pioneered by UPA and popularized by Hanna-Barbera, and adapted by other studios as cartoons moved from movie theaters to television.[1]

Although most animation studios are now using digital technologies in their productions, there is a specific style of animation that depends on film. Cameraless animation, made famous by moviemakers like Norman McLaren, Len Lye and Stan Brakhage, is painted and drawn directly onto pieces of film, and then run through a projector.

Venues

When it is initially produced, a feature film is often shown to audiences in a movie theater or cinema. The first theater designed exclusively for cinema opened in Pittsburgh, Pennsylvania in 1905.[2] Thousands of such theaters were built or converted from existing facilities within a few years.[3] In the United States, these theaters came to be known as nickelodeons, because admission typically cost a nickel (five cents).

Typically, one film is the featured presentation (or feature film). Before the 1970s, there were "double features"; typically, a high quality "A picture" rented by an independent theater for a lump sum, and a "B picture" of lower quality rented for a percentage of the gross receipts. Today, the bulk of the material shown before the feature film consists of previews for upcoming movies and paid advertisements (also known as trailers or "The Twenty").

Historically, all mass marketed feature films were made to be shown in movie theaters. The development of television has allowed films to be broadcast to larger audiences, usually after the film is no longer being shown in theaters. Recording technology has also enabled consumers to rent or buy copies of films on VHS or DVD (and the older formats of laserdisc, VCD and SelectaVision — see also videodisc), and Internet downloads may be available and have started to become revenue sources for the film companies. Some films are now made specifically for these other venues, being released as made-for-TV movies or direct-to-video movies. The production values on these films are often considered to be of inferior quality compared to theatrical releases in similar genres, and indeed, some films that are rejected by their own studios upon completion are distributed through these markets.

The movie theater pays an average of about 55% of its ticket sales to the movie studio, as film rental fees.[citation needed] The actual percentage starts with a number higher than that, and decreases as the duration of a film's showing continues, as an incentive to theaters to keep movies in the theater longer. However, today's barrage of highly marketed movies ensures that most movies are shown in first-run theaters for less than 8 weeks. There are a few movies every year that defy this rule, often limited-release movies that start in only a few theaters and actually grow their theater count through good word-of-mouth and reviews. According to a 2000 study by ABN AMRO, about 26% of Hollywood movie studios' worldwide income came from box office ticket sales; 46% came from VHS and DVD sales to consumers; and 28% came from television (broadcast, cable, and pay-per-view).[citation needed]

Technology

Film stock consists of transparent celluloid, acetate, or polyester base coated with an emulsion containing light-sensitive chemicals. Cellulose nitrate was the first type of film base used to record motion pictures, but due to its flammability was eventually replaced by safer materials. Stock widths and the film format for images on the reel have had a rich history, though most large commercial films are still shot on (and distributed to theaters) as 35 mm prints.

Originally moving picture film was shot and projected at various speeds using hand-cranked cameras and projectors; though 1000 frames per minute (16⅔ per second) is generally cited as a standard silent speed, research indicates most films were shot between 16 and 23 fps and projected from 18 fps on up (often reels included instructions on how fast each scene should be shown) [1]. When sound film was introduced in the late 1920s, a constant speed was required for the sound head. 24 frames per second was chosen because it was the slowest (and thus cheapest) speed which allowed for sufficient sound quality. Improvements since the late 19th century include the mechanization of cameras — allowing them to record at a consistent speed, quiet camera design — allowing sound recorded on-set to be usable without requiring large "blimps" to encase the camera, the invention of more sophisticated filmstocks and lenses, allowing directors to film in increasingly dim conditions, and the development of synchronized sound, allowing sound to be recorded at exactly the same speed as its corresponding action. The soundtrack can be recorded separately from shooting the film, but for live-action pictures many parts of the soundtrack are usually recorded simultaneously.

As a medium, film is not limited to motion pictures, since the technology developed as the basis for photography. It can be used to present a progressive sequence of still images in the form of a slideshow. Film has also been incorporated into multimedia presentations, and often has importance as primary historical documentation. However, historic films have problems in terms of preservation and storage, and the motion picture industry is exploring many alternatives. Most movies on cellulose nitrate base have been copied onto modern safety films. Some studios save color films through the use of separation masters — three B&W negatives each exposed through red, green, or blue filters (essentially a reverse of the Technicolor process). Digital methods have also been used to restore films, although their continued obsolescence cycle makes them (as of 2006) a poor choice for long-term preservation. Film preservation of decaying film stock is a matter of concern to both film historians and archivists, and to companies interested in preserving their existing products in order to make them available to future generations (and thereby increase revenue). Preservation is generally a higher-concern for nitrate and single-strip color films, due to their high decay rates; black and white films on safety bases and color films preserved on Technicolor imbibition prints tend to keep up much better, assuming proper handling and storage.

Some films in recent decades have been recorded using analog video technology similar to that used in television production. Modern digital video cameras and digital projectors are gaining ground as well. These approaches are extremely beneficial to moviemakers, especially because footage can be evaluated and edited without waiting for the film stock to be processed. Yet the migration is gradual, and as of 2005 most major motion pictures are still recorded on film.

Future state

While motion picture films have been around for more than a century, film is still a relative newcomer in the pantheon of fine arts. In the 1950s, when television became widely available, industry analysts predicted the demise of local movie theaters. Despite competition from television's increasing technological sophistication over the 1960s and 1970s, such as the development of color television and large screens, motion picture cinemas continued. In the 1980s, when the widespread availability of inexpensive videocassette recorders enabled people to select films for home viewing, industry analysts again wrongly predicted the death of the local cinemas.

In the 1990s and 2000s, the development of digital DVD players, home theater amplification systems with surround sound and subwoofers, and large LCD or plasma screens enabled people to select and view films at home with greatly improved audio and visual reproduction. These new technologies provided audio and visual that in the past, only local cinemas had been able to provide: a large, clear widescreen presentation of a film with a full-range, high-quality multi-speaker sound system. Once again, industry analysts predicted the demise of the local cinema. Local cinemas will be changing in the 2000s and moving towards digital screens, a new approach which will allow for easier, quicker distribution of films (via satellite or hard disks), a development which may give local theaters a reprieve from their predicted demise.

Electron

The name "electron" comes from the Greek word for amber, ήλεκτρον. This material played an essential role in the discovery of electrical phenomena. The ancient Greeks knew, for example, that rubbing a piece of amber with fur left an electric charge on its surface, which could then create sparks. For more about the history of the term electricity, see History of electricity.

The electron as a unit of charge in electrochemistry was posited by G. Johnstone Stoney in 1874, who also coined the term electron in 1894. During the late 1890s a number of physicists posited that electricity could be conceived of as being made of discrete units, which were given a variety of names, but their reality had not been confirmed in a compelling way.

The discovery that the electron was a subatomic particle was made in 1897 by J.J. Thomson at the Cavendish Laboratory at Cambridge University, while he was studying cathode ray tubes. A cathode ray tube is a sealed glass cylinder in which two electrodes are separated by a vacuum. When a voltage is applied across the electrodes, cathode rays are generated, causing the tube to glow. Through experimentation, Thomson discovered that the negative charge could not be separated from the rays (by the application of magnetism), and that the rays could be deflected by an electric field. He concluded that these rays, rather than being waves, were composed of negatively charged particles he called "corpuscles". He measured their mass-to-charge ratio and found it to be over a thousand times smaller than that of a hydrogen ion, suggesting that they were either very highly charged or very small in mass. Later experiments by other scientists upheld the latter conclusion. Their mass-to-charge ratio was also independent of the choice of cathode material and the gas originally on vacuum tube. This led Thomson to conclude that they were universal among all materials.

The electron's charge was carefully measured by Robert Millikan in his oil-drop experiment of 1909.

The periodic law states that the chemical properties of elements largely repeat themselves periodically and is the foundation of the periodic table of elements. The law itself was initially explained by the atomic mass of the element. However, as there were anomalies in the periodic table, efforts were made to find a better explanation for it. In 1913, Henry Moseley introduced the concept of the atomic number and explained the periodic law in terms of the number of protons each element has. In the same year, Niels Bohr showed that electrons are the actual foundation of the table. In 1916, Gilbert Newton Lewis explained the chemical bonding of elements by electronic interactions.

[edit] Classification

The electron is in the class of subatomic particles called leptons, which are believed to be fundamental particles.

As with all particles, electrons can also act as waves. This is called the wave-particle duality, also known by the term complementarity coined by Niels Bohr and can be demonstrated using the double-slit experiment.

The antiparticle of an electron is the positron, which has the same mass but positive rather than negative charge. The discoverer of the positron, Carl D. Anderson, proposed calling standard electrons negatrons, and using electron as a generic term to describe both the positively and negatively charged variants. This usage never caught on and is rarely, if ever, encountered today.

[edit] Properties and behavior

Electrons have an electric charge of −1.6022 × 10−19 coulomb, a mass of 9.11 × 10−31 kg based on charge/mass measurements and a relativistic rest mass of about 0.511 MeV/c2. The mass of the electron is approximately 1/1836 of the mass of the proton. The common electron symbol is e−. [1]

According to quantum mechanics, electrons can be represented by wavefunctions, from which a calculated probabilistic electron density can be determined. The orbital of each electron in an atom can be described by a wavefunction. Based on the Heisenberg uncertainty principle, the exact momentum and position of the actual electron cannot be simultaneously determined. This is a limitation which, in this instance, simply states that the more accurately we know a particle's position, the less accurately we can know its momentum, and vice versa.

The electron has spin ½ and is a fermion (it follows Fermi-Dirac statistics). In addition to its intrinsic angular momentum, an electron has an intrinsic magnetic moment along its spin axis.

Electrons in an atom are bound to that atom; electrons moving freely in vacuum, space or certain media are free electrons that can be focused into an electron beam. When free electrons move, there is a net flow of charge, this flow is called an electric current. The drift velocity of electrons in metal wires is on the order of mm/hour. However, the speed at which a current at one point in a wire causes a current in other parts of the wire is typically 75% of light speed.

In some superconductors, pairs of electrons move as Cooper pairs in which their motion is coupled to nearby matter via lattice vibrations called phonons. The distance of separation between Cooper pairs is roughly 100 nm. (Rohlf, J.W.)

A body has an electric charge when that body has more or fewer electrons than are required to balance the positive charge of the nuclei. When there is an excess of electrons, the object is said to be negatively charged. When there are fewer electrons than protons, the object is said to be positively charged. When the number of electrons and the number of protons are equal, their charges cancel each other and the object is said to be electrically neutral. A macroscopic body can develop an electric charge through rubbing, by the phenomenon of triboelectricity.

When electrons and positrons collide, they annihilate each other and produce pairs of high energy photons or other particles. On the other hand, high-energy photons may transform into an electron and a positron by a process called pair production, but only in the presence of a nearby charged particle, such as a nucleus.

The electron is currently described as a fundamental particle or an elementary particle. It has no substructure. Hence, for convenience, it is usually defined or assumed to be a point-like mathematical point charge, with no spatial extension. However, when a test particle is forced to approach an electron, we measure changes in its properties (charge and mass). This effect is common to all elementary particles: Current theory suggests that this effect is due to the influence of vacuum fluctuations in its local space, so that the properties measured from a significant distance are considered to be the sum of the bare properties and the vacuum effects (see renormalization).

The classical electron radius is 2.8179 × 10−15 m. This is the radius that is inferred from the electron's electric charge, by using the classical theory of electrodynamics alone, ignoring quantum mechanics. Classical electrodynamics (Maxwell's electrodynamics) is the older concept that is widely used for practical applications of electricity, electrical engineering, semiconductor physics, and electromagnetics; quantum electrodynamics, on the other hand, is useful for applications involving modern particle physics and some aspects of optical, laser and quantum physics.

Based on current theory, the speed of an electron can approach, but never reach, c (the speed of light in a vacuum). This limitation is attributed to Einstein's theory of special relativity which defines the speed of light as a constant within all inertial frames. However, when relativistic electrons are injected into a dielectric medium, such as water, where the local speed of light is significantly less than c, the electrons will (temporarily) be traveling faster than light in the medium. As they interact with the medium, they generate a faint bluish light, called Cherenkov radiation.

The effects of special relativity are based on a quantity known as γ or the Lorentz factor. γ is a function of v, the velocity of the particle. It is defined as:

\gamma = \frac{1}{\sqrt{1 - \left (\frac{v^{2}}{c^{2}}\right )}}

The energy necessary to accelerate a particle is γ minus one times the rest mass. For example, the Stanford linear accelerator can accelerate an electron to roughly 51 GeV [2]. This gives a gamma of 100,000, since the rest mass of an electron is 0.51 MeV/c² (the relativistic mass of this electron is 100,000 times its rest mass). Solving the equation above for the speed of the electron (and using an approximation for large γ) gives:

v = \left(1-\frac {1} {2} \gamma ^{-2}\right)c = 0.999\,999\,999\,95\,c.

[edit] In practice

[edit] In the universe

Scientists believe that the number of electrons existing in the known universe is at least 1079. This number amounts to an average density of about one electron per cubic metre of space. Astronomers have determined that 90% of all of the detectable mass in the universe is hydrogen, which is made of one electron and one proton.

Based on the classical electron radius and assuming a dense sphere packing, it can be calculated that the number of electrons that would fit in the observable universe is on the order of 10130.

[edit] In industry

Electron beams are used in welding, lithography, scanning electron microscopes and transmission electron microscopes. LEED and RHEED are also important tools where electrons are used.

They are also at the heart of cathode ray tubes, which are used extensively as display devices in laboratory instruments, computer monitors and television sets. In photomultiplier tubes, one photon strikes the photocathode, initiating an avalanche of electrons that produces a detectable current.

[edit] In the laboratory

Electron microscopes are used to magnify details up to 500,000 times. Quantum effects of electrons are used in Scanning tunneling microscope to study features at the atomic scale.

[edit] In Medicine

In radiation therapy, electron beams are used for treatment of superficial tumours.

[edit] In theory

In relativistic quantum mechanics, the electron is described by the Dirac Equation which defines the electron as a (mathematical) point. In quantum field theory, the behavior of the electron is described by quantum electrodynamics (QED), a U(1) gauge theory. In Dirac's model, an electron is defined to be a mathematical point, a point-like, charged "bare" particle surrounded by a sea of interacting pairs of virtual particles and antiparticles. These provide a correction of just over 0.1% to the predicted value of the electron's gyromagnetic ratio from exactly 2 (as predicted by Dirac's single-particle model). The extraordinarily precise agreement of this prediction with the experimentally determined value is viewed as one of the great achievements of modern physics.[3]

In the Standard Model of particle physics, the electron is the first-generation charged lepton. It forms a weak isospin doublet with the electron neutrino; these two particles interact with each other through both the charged and neutral current weak interaction. The electron is very similar to the two more massive particles of higher generations, the muon and the tau lepton, which are identical in charge, spin, and interaction but differ in mass.

The antimatter counterpart of the electron is the positron. The positron has the same amount of electrical charge as the electron, except that the charge is positive. It has the same mass and spin as the electron. When an electron and a positron meet, they may annihilate each other, giving rise to two gamma-ray photons emmited at roughly 180° to each other. If the electron and positron had negligible momentum, each gamma ray will have an energy of 0.511 MeV. See also Electron-positron annihilation.

Electrons are a key element in electromagnetism, a theory that is accurate for macroscopic systems, and for classical modelling of microscopic systems.

Acting

Acting

Acting is the work of an actor or actress, which is a person in theatre, television, film, or any other storytelling medium who tells the story by portraying a character and, usually, speaking or singing the written text or play. From the Latin word agĕre meaning "to do", this is precisely what acting is. In acting, an actor suppresses or augments aspects of their personality in order to reveal the actions and motivations of the character for particular moments in time. The actor is said to be "assuming the role" of another, usually for the benefit of an audience, but also because it can bring one a sense of artistic satisfaction. The first actor is believed to be Thespis of Icaria, a man of ancient Greece. He supposedly was the first to break away from the traditional singing chorus of the time ("plays" of this time involved only a chorus whom sang a story reminiscent of an opera), literally stepping away from the chorus and speaking to them as a separate character in the story. This may only be a legend, but in his honor a word was crafted: thespian, meaning any sort of performer but chiefly an actor. The International Thespian Society, a society comparable to a fraternity (yet possessing the troop system of the Girl Scouts) for students involved in the arts has also been named in his honor.

Actors are generally expected to possess a number of skills, including good vocal projection, clarity of speech, physical expressiveness, a good sense of perspective, emotional availability, a well developed imagination, the ability to analyze and understand dramatic text, and the ability to emulate or generate emotional and physical conditions. Well-rounded actors are often also skilled in singing, dancing, emotional expressiveness, imitating dialects and accents, improvisation, observation and emulation, mime, stage combat, and performing classical texts such as Shakespeare. Many actors train at length in special programs or colleges to develop these skills, which have a wide range of different artistic philosophies and processes. Modern pioneers in the area of acting have included Mani Madhava Chakyar, Konstantin Stanislavski, Jerzy Grotowski, Lee Strasberg, Uta Hagen, Stella Adler, Michael Chekhov, Viola Spolin, Sanford Meisner, Bertolt Brecht, and Maria Ouspenskaya.

The Professional Actor

Not all people working as an actor in film, television or theatre are professionally trained, but the vast majority are. Chances of succeeding as an actor are greatly enhanced by going to a drama school (or acting school). Most offer two to three years extensive and intense training on all aspects of acting, including work on voice, gesture, posture, facial expression, awareness of space and movement, either across the stage or around the camera, but generally both. Applications to drama schools are through auditions, and those who show their talent well are offered a place. Anybody over the age of 18 can usually apply to drama school to become a professional actor or actress.

Drama / Acting Schools

British Schools

* Academy Of Live & Recorded Arts
* Birmingham School Of Acting
* Bristol Old Vic Theatre School
* Central School Of Speech & Drama
* East 15 Acting School
* Liverpool Institute Of Performing Arts
* London Academy Of Music & Dramatic Art (LAMDA)
* Manchester Metropolitan University School Of Theatre
* Oxford School Of Drama
* Rose Bruford College
* Royal Academy Of Dramatic Art (RADA)
* Royal Scottish Academy Of Music & Drama
* Royal Welsh College Of Music & Drama


American Schools

* Chapman University: School of Film and Telivision
* FSU: Film School
* EMAS: Los Angeles Acting School
* Loyola Marymount University: School of Film and Television
* University of Southern California: School of Cinema Television
* NYU: Tisch School of the Arts Maurice Kanbar Institute of Film and Television

Australian Schools

* NIDA: National Insitute of Dramatic Art
* VCA: Victorian College of the Arts
* WAAPA: Western Australian Academy of Performing Arts
* ACA: Actors Centre Australia
* ACTT: Actors' College of Theatre and Television
* HSPA: Hunter School of the Performing Arts

Western Philosophy

Main branches of philosophyTo give an exhaustive list of the main divisions of philosophy is difficult, because there have been different, equally acceptable divisions at different times, and the divisions are often relative to the philosophical concerns of a particular period. They also overlap considerably. Nevertheless, Metaphysics, Epistemology, Logic, Moral Philosophy, and perhaps Politics (which Aristotle saw as part of Ethics) are considered to be the main branches. Most other areas are mixtures or versions of those. For example, the philosophy of various subjects (such as science, history, religion, mind, art) turns out to fall into the main divisions.

Metaphysics was first studied systematically by Aristotle, though he did not use that term. He calls it 'first philosophy' (or sometimes just 'wisdom') and says it is the subject which deals with 'first causes and the principles of things'. It is the highest science of all, because it is the most general, and its truths explain the truths of all other sciences.[6]The modern meaning of the term is any enquiry dealing with the ultimate nature of what exists. Within metaphysics, ontology is the enquiry into the meaning of existence itself, sometimes seeking to specify what general types of things exist (though sometimes the term is taken to be equivalent to metaphysics itself). The philosophy of mind, since it ultimately concerns the question of whether mind or consciousness exists, and what it is, is part of metaphysics.

Epistemology is concerned with the nature and scope of knowledge, and whether knowledge is possible at all. Its central concern is the challenge posed by skepticism, that all our beliefs and thoughts may be somehow illusory or mistaken (such as if our waking life were really a dream).

Ethics or 'moral philosophy', is concerned with questions of how agents should or ought to act. For example, Plato's early dialogues search for definitions of virtues like temperance, justice, courage, piety. Metaethics, the study of whether value judgments can be objective at all, is generally distinguished from particular ethical systems (for example, Aristotelian, Kantian, or utilitarian) which attempt to prescribe principles of good behaviour.

Logic has two broad divisions: mathematical logic (dealing with formal logical apparatus) and what is now called philosophical logic. Often the term is taken to mean only the first of these. The second has come to include most of those topics traditionally treated by logic in general; it is concerned with characterising notions like inference, rational thought, truth, and contents of thoughts, in the most fundamental ways possible, sometimes trying to model them using modern formal logic.

Naturalism

Naturalism is any of several philosophical stances, typically those descended from materialism and pragmatism, that do not distinguish the supernatural (including strange entities like non-natural values, and universals as they are commonly conceived) from nature. Naturalism does not necessarily claim that phenomena or hypotheses commonly labeled as supernatural do not exist or are wrong, but insists that all phenomena and hypotheses can be studied by the same methods and therefore anything considered supernatural is either nonexistent, unknowable, or not inherently different from natural phenomena or hypotheses.

Any method of inquiry or investigation or any procedure for gaining poo that limits itself to natural, physical, and material approaches and explanations can be described as naturalistic.

Many modern philosophers of science[1][2] use the terms methodological naturalism or scientific naturalism to refer to the long standing convention in science of the scientific method, which makes the methodological assumption that observable effects in nature are best explainable only by similarly natural causes, and with irrelevance to the assumption of the existence or non-existence of supernatural elements, and so considers supernatural explanations for such events to be outside of science. They contrast this with the approach known as ontological naturalism or metaphysical naturalism, which refers to the metaphysical belief that the natural world (including the universe) is all that exists, and therefore nothing supernatural exists.

This distinction between approaches to the philosophy of naturalism is made by philosophers supporting science and evolution in the creation–evolution controversy to counter the tendency of some proponents of Creationism or intelligent design to refer to methodological naturalism as scientific materialism or as methodological materialism and conflate it with metaphysical naturalism to support their claim that modern science is atheistic. They contrast this with their preferred approach of a revived natural philosophy which welcomes supernatural explanations for natural phenomena and supports "theistic science" or pseudoscience.

king named Tuptim

Mrs. Anna Leonowens, a widow from Wales, arrives in Bangkok with her young son to teach English to the children of the royal household. She threatens to leave when the house she was promised in the contract is not available, but is dissuaded from doing so when the King presents to her his children. The King eventually honors his promise of a suitable house. He also very much wishes to absorb western knowledge, but is sometimes conflicted over how to reconcile western ways with his own.

Meanwhile, a new (literate) slave for the king named Tuptim -- a gift from the king of Burma -- befriends "Mrs. Anna" and borrows her copy of Uncle Tom's Cabin. She transforms it into the Siamese ballet Small House of Uncle Thomas, which is presented amidst the welcoming of emissaries from Great Britain, making it clear she is unhappy being a slave to the King. After the performance, when she tries to escape with her lover, she is apprehended. Anna prevents the King from beating her, causing him to run away in shame and hide away for weeks.

Anna, thinking that she can no longer be of any use, is just about to leave Siam when she is told that the King is dying. She decides to stay in order to help his young son, Crown Prince Chulalongkorn -- her favorite pupil -- to rule his people.