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Badminton

Badminton

This article is about the racquet sport badminton. For other uses of the name, see Badminton (disambiguation). Badminton (disambiguation) Badminton is a racquet sport played by either two opposing players (singles) or two opposing pairs (doubles). The game of badminton is superficially similar to that of tennis. Players at opposite ends of the court aim to hit a shuttlecock, more informally called a birdie, over the net so that it lands inside the marked boundaries of the court, and aim to prevent their opponents from doing the same. Unlike a tennis ball, the shuttlecock flies with a lot of drag, and will not bounce significantly. The shuttlecock is always volleyed, and a point ends as soon as it touches the ground. Badminton racquets have long handles, to make it easier to impart a great deal of momentum to overcome the drag. The racquets are also much lighter than tennis racquets, because the shuttlecock is light. Badminton is the fastest sport in the world with shuttles reaching speeds of up to 332 km/h. Fu Haifeng of China set the unofficial record July 3, 2005. Although the size of a badminton court is smaller than that of a tennis court, the distance run by a player in a match is usually much greater than that in tennis. This is due, in part, to the fact that the entire court must be covered by the player as the shuttlecock is not allowed to bounce before being returned. Also, the rallies of each point tend to be much longer than tennis. This is true even though winning a 'shutout' match in badminton requires only winning 30 points (15-0, 15-0, in a Men's Single match) whereas in tennis it would require 72 points (6-0, 6-0, 6-0). The game of badminton may look easy to play, but it can be physically more tiring than tennis since the tennis ball travels at a much slower speed as compared to a shuttlecock. Speed, reaction, and endurance are all important to being a successful badminton player. From a fitness perspective a close comparison can be made to squash which also has the same explosive starts. As in tennis, there are typically five events: men's singles, women's singles, men's doubles, women's doubles and mixed doubles (each pair is composed of one man and one woman).

The service court

Ones decide between two service courts. There is the service court for singles, which is 5.18 meters wide and 13.40 meters long. The service court for doubles is 6.10 meters wide and 11.88 meters long. The service court is divided in two parts. In the middle of the court there is a net, which is 1.55 meters high. The short service lines go away 1.98 meters from the net. Left service court and right service court are divided by the center line.

Equipment

squash Racquet: Traditionally racquets were made of wood. Later on aluminium or other light metals became the material of choice. Now, almost all professional badminton racquets are composed of carbon fiber composite (graphite reinforced plastic). Carbon fiber has an excellent strength to weight ratio, is stiff, and gives excellent kinetic energy transfer. However, some low-end models still use steel or aluminum for some or all of the racquet. String: Perhaps one of the most overlooked areas of badminton equipment is the string. Different types of string have different response properties. Durability generally varies with performance. Most strings are 21 gauge in thickness and strung at 18 to 30+ lbf (80 to 130+ newtons) of tension. Racquets strung at lower tensions (18 to 21 lbf or 80 to 95 N) generate greater power while racquets strung at higher tensions (21+ lbf, over 95 N) provide greater control. Players' personal preferences play a strong role in string selection. Shoes: Because acceleration across the court is so important, players need excellent grip with the floor at all times. Badminton shoes need a gum sole for good grip, reinforced side walls for durability during drags, and shock dispersion technology for jumping; badminton places a lot of stress on the knees and ankles. The Japanese manufacturer Yonex dominates the badminton equipment market, making racquets, shoes, and everything in between.

Playing the game

Each player or pair takes position on either side of a net on a rectangular court marked on the floor, as shown in the diagrams. The object of the game is to hit a shuttlecock (normally shortened to "shuttle" or "cock"; more colloquially, "bird" or "birdie"), using a racquet, over the net onto the court within the marked boundaries before the opposing player or pair can hit it back. For every time this is achieved by the team currently serving, the serving player or pair scores one point. After winning a point the same player serves again, and continues to serve as long as they continue to win points. If the non-serving team wins the rally, no point is scored but instead there is a change of server. In doubles, one server starts the game, and after losing a rally the serve switches to the opposing team. From then on, both players on a team take turns serving before the serve switches back to their opponents. The player on the right-hand serving side always begins the serving.

The Rules

At the start of a match, a coin is tossed. The side that wins the toss may choose whether to serve first, or may choose which end of the court to play. The other side exercises the remaining choice. In less formal settings, the shuttle may be hit into the air to determine which side serves: the shuttle lands pointing to the serving side. Scoring The first player or pair to reach 15 points (11 points for women's singles) wins the game. If the score reaches 14-all (10-all for women's singles) the receiving side can choose to "set" and hence extend the game by 3 points, i.e. the first to reach 17 (or 13) points wins. If the non-serving side chooses not to set, the game is decided by a single point, i.e. the first to reach 15 (or 11) points wins. A badminton match can be made up of any odd number of games (usually 3). The winner of the match is the first to win more than half the number of games (e.g. the first to win 3 games in a 5 game match). Service The serve must be in an upwards direction, to land in the diagonally opposite service court. A point is only added to the score on service. Unlike tennis, there is no "let" on service if the shuttle hits the tape. At the start of a doubles game, the first side to serve will only continue serving until they lose a rally. After that, the serve will pass to the opponents, and for the remainder of the game both members of a serving pair will have an opportunity to serve. A server must change service courts after each rally won, so that he serves to the other opponent. The receiving pair, however, will not vary their positions in this way. When a pair have just regained the service, the first serve is always delivered by the player in the right-hand service court. In singles each player has only one serve at a time; if the serve is lost, it passes to the opponent. Faults When players commit a fault, they lose the rally. The most common fault is for a player to fail to return the shuttle before it hits the floor, or to return it so that it lands out of court. It is also a fault if the shuttle touches the person or dress of a player, or in doubles if both players hit the shuttle. At lower levels of play, players often commit service faults without realising. At the moment of impact on service, the shuttle must be below the waist, and the whole of the racket head must be below the hand holding the racket. These rules are designed to limit the attacking options of the server. Lets If a let is called, the rally is restarted. Lets are rare in professional play; they occur whenever some unexpected circumstance arises that interferes with the rally. For example, a let is called if the shuttle passes over the net and then becomes entangled in the net (except on service, when this is deemed a fault).

Strategy

To win in badminton, players need to employ a wide variety of strokes in the right situations. These range from powerful jumping smashes to delicate tumbling net returns. The smash is a powerful overhead stroke played steeply downwards into the middle or rear of the opponents' court; it is similar to a tennis serve, but much faster: the shuttlecock can travel at 300km/h (186 mph). This is a very effective stroke, and pleases the crowds, but smashing is only one part of the game. Often rallies finish with a smash, but setting up the smash requires subtler strokes. For example, a netshot can force the opponent to lift the shuttle, which gives an opportunity to smash. If the netshot is tight and tumbling, then the opponent's lift will not reach the back of the court, which makes the subsequent smash much harder to return. Deception is also important. Expert players make the preparation for many different strokes look identical, so that their opponents cannot guess which stroke will be played. For many strokes, the shuttlecock can be sliced to change its direction; this allows a player to move his racket in a different direction to the trajectory of the shuttlecock. If an opponent tries to anticipate the stroke, he will move in the wrong direction and may be unable to change his body momentum in time to reach the shuttlecock. Doubles: In doubles, each side has two players. Both sides will try to gain and maintain the attack, hitting downwards as much as possible. Usually one player will strive to stay at the back of the court and the other at the front, which is an optimal attacking position: the back player will smash and occasionally drop the shuttlecock to the net, and the front player will try to intercept any flat returns or returns to the net. Typical play involves hitting the shuttle in a trajectory as low and flat as possible, to avoid giving away the attack. A side that hits a high shot must prepare for a smash and retreat to a side-by-side defensive position, with each player covering half of the court. The first serve is usually a low serve to force the other side to lift the shuttle. A "flick serve", in which the player will pretend to serve low but hit it high to catch the receiver off-guard, is sporadically used throughout the game. Doubles is a game of speed, aggression, and agility. Singles: Players will serve high to the far back end of the court, although at the international level low serves are now frequently used as well. The singles court is narrower than the doubles court, but the same length. Since one person needs to cover the entire court, singles tactics are based on forcing the opponent to move as much as possible; this means that singles shots are normally directed to the corners of the court. The depth of the court is exploited by combining clears (high shots to the back) with drops (soft downwards shots to the front). Smashing is less prominent in singles than in doubles because players are rarely in the ideal position to execute a smash, and smashing out of position leaves the smasher very vulnerable if the shot is returned. At high levels of play, singles demands extraordinary fitness. It is a game of patient tactical play, unlike the all-out aggression of doubles. Mixed doubles: In this discipline, a man and a woman play as a doubles pair. Mixed doubles is similar to "level" doubles (where pairs are of the same gender), but important changes in tactics are usually made in order to accommodate the difference in strength between men and women. In mixed doubles, both pairs try to maintain an attacking formation with the woman at the front and the man at the back. This is because the male players are substantially stronger, and can therefore produce more powerful smashes. As a result, mixed doubles requires greater tactical awareness and subtler positional play. Clever opponents will try to reverse the ideal position, by forcing the woman towards the back or the man towards the front. In order to protect against this danger, mixed players must be careful and systematic in their shot selection.

History

Sports played with a shuttlecock and racquets probably developed in ancient Greece around 2000 years ago but are also mentioned in India and China. An early ancestor of the game may have been the Chinese game of jianzi which involves using a shuttlecock but no racquet. Instead the object was manipulated with the feet. The object of the game is to keep the shuttlecock from touching the ground as long as possible without using the hands. jianzi In England since medieval times a children's game called Battledores and Shuttlecocks was popular. Children would use paddles (Battledores) and work together to keep the Shuttlecock up in the air and prevent it from reaching the ground. It was popular enough to be a nuisance on the street of London in 1854 when the magazine Punch published this cartoon. The British took the game to Japan, China and Siam as they colonised Asia, and it soon became a children's game there. The competitive sport of badminton was invented by British Army officers in Pune, India in the 19th century when they added a net and played it competitively. As the city of Pune was formerly known as Poona, the game was also known as Poona at that time. Soldiers brought the game back to England in the 1850s. The sport got its current name in 1860 in a pamphlet by Isaac Spratt, a London toy dealer, entitled "Badminton Battledore - a new game". This described the game as played at Badminton House, the Duke of Beaufort's estate in Gloucestershire, England. The first official set of rules was written by the Bath Badminton Club in 1877. The Badminton Association of England was formed in 1893 and the first international championship took place in 1899 with the All England Championships. Badminton became a popular sport in the world, primarily in East and Southeast Asia, which currently dominates the sport, and in the Scandinavian countries. The International Badminton Federation (IBF) was established in 1934 and had England, Ireland, Scotland, Wales, Denmark, Holland, Canada, New Zealand and France as by founding members. India joined as an affiliate in 1936. In the Extraordinary General Meeting of December 2004, a proposal to move the IBF office from the UK to Kuala Lumper, Malaysia was tabled and subsequently approved amid heated discussion. It became a Summer Olympic sport at the Barcelona Olympics in 1992. Indonesia and Korea shared the gold medal with two each that year. The IBF has been tinkering with the scoring system in an effort to commercialize the sport. A recent experiment of playing a match of 5 games of 7 points instead of the current 3 games of 15 points failed to garner the support of the fans, players and coaches after a year. The next experiment is to have 3 games of 21 points where every rally will result in a point being awarded (just like volleyball) which will debut in the next World Cup to be held in December 2005 in China.

Sources

"Badminton- Schlagarten und Flugkurven aus: Badminton in der Schule. Eine Informationsmappe für Lehrer; Deutscher Badminton-verband e.V. (1. Auflage, Mühlheim an der Ruhr, 1991) " Cartoon taken from the [http://john-leech-archive.org.uk John Leech Archive] which gives the artist as John Leech and the date as 1854.

External links

- [http://www.badmintoncentral.com/ Badminton Central]
- [http://www.badders.com/ Badders.com]
- [http://www.badmintonforum.com/ Badminton Forum]
- [http://www.intbadfed.org/ International Badminton Federation]
- [http://www.worldbadminton.net/ WorldBadminton.net]
- [http://www.eurobadminton.org/ European Badminton Union]
- [http://www.yumaoclub.com/ Chinese Badminton Site(羽毛球拍)]
- [http://www.tradgames.org.uk/games/Battledore-Shuttlecock.htm History of the game]
- [http://badminton-indonesia.com/ Indonesian Badminton Site]
- [http://dmoz.org/Sports/Badminton/ Badminton] from the Open Directory Project
- [http://www.usabadminton.org/ USA Badminton]
- [http://www.schsb.com.com/ SCHSB.COM Category:Racquet sports Category:Olympic sports Category:Badminton ko:배드민턴 ms:Badminton ja:バドミントン simple:Badminton th:แบดมินตัน

Badminton (disambiguation)

The name Badminton may refer to:
- Badminton, South Gloucestershire, a village in England giving its name to
- Badminton House, the estate of the Duke of Beaufort in Gloucestershire
- home of the Badminton Horse Trials
- the sport of badminton, named after Badminton House where a version of the sport was developed
- Badminton School, in Bristol

Shuttlecock

A shuttlecock is a high-drag projectile used in the sport of badminton. It has an open conical shape, with a rounded head at the apex of the cone traditionally made of cork and a skirt traditionally of sixteen overlapping goose feathers. Best shuttlecocks are made from feathers from the left goose wing. For most casual players, the cork-and-feather construction has been replaced by the use of a plastic (usually nylon) or rubber head and a plastic (usually nylon) skirt. The feather shuttlecock is still used by serious players and for competitions. The feathered variety is more expensive and far more likely to break during a match, and also has to be hit about three times as hard. The shuttlecock is also called a "birdie", "bird", "cock" or "shuttle". The "shuttle" part of the name was probably derived from its back-and-forth motion during the game, resembling the shuttle of a loom, and the "cock" from the feathers of the traditional shuttlecock, referring to a bird's crest. The shuttlecock's shape makes it extremely aerodynamically stable. Regardless of initial orientation, it will turn to fly head first, and remain in the head-first orientation. The feathers provide a lot of drag (less so in a plastic construction). It is this consistent high-drag behavior that makes badminton distinctive. The shuttlecock's aerodynamic behavior was consciously replicated in the design of the spacecraft SpaceShipOne. Its "feathered" flight mode is a very stable high-drag configuration, used to make the flight insensitive to orientation during atmospheric reentry. Shuttlecock is also used as the English name of the sport Jianzi, which is also played with a shuttlecock. = External links = [http://www.shuttlecock-europe.org/ Shuttlecock Federation of Europe] [http://www.shuttlecock-federation.org/ International Shuttlecock Federation] [http://www.federfussballbund.de/ German Shuttlecock Federation] [http://www.featherball.net/ Greek Shuttlecock Federation] [http://www.labtoll.hu/ Hungarian Shuttlecock Federation] [http://www.hkshuttlecock.org/ Hong Kong Shuttlecock Association] [http://www.jianqiu.net/ Chinese Shuttlecock Association] [http://www.dacau.fr.st/ French Shuttlecock Association] [http://shuttlecock.uhome.net/ Vietnamese Shuttlecock Association] [http://staff.akumiitti.fi/hsjp Finnish Shuttlecock Association] [http://www.shuttlecock.click.hu/ Slovakian Shuttlecock Association] [http://home.kimo.com.tw/wwww1030/ Taiwanese Shuttlecock Association] Category:Badminton Category:Shuttlecock Category:Racquet sports Category:Team sports

Tennis ball

A tennis ball is the bouncing ball used in the game of tennis. Tennis balls in the early days of tennis were made of leather stuffed with hair or wool. Starting in the 18th century, ¾" strips of wool were wound tightly around a nucleus made by rolling a number of strips into a little ball. String was then tied in many directions around the ball and a white cloth covering sewn around the ball. With the introduction of lawn tennis in the 1870’s, vulcanised rubber was first used to manufacture balls. The modern tennis ball is comprised of two major parts, the inner core and the outer cloth covering. The inner core is constructed of two half-shell pieces of formed rubber, which are joined together with adhesive to form a single core. Two dumbbell shaped pieces of cloth are attached to the ball core by adhesive to give the tennis ball its classic appearance. The thickness and density of the ball cloth is matched to the court type for which the ball is designed. The balls currently in use can be subdivided into two categories of pressurised and pressureless. A pressurised ball is constructed when the core is filled with air (or a gas such as nitrogen) at a pressure that is above the ambient pressure. These balls lose their pressure, and hence playing properties, over time. A non-pressurised ball is made from a thicker rubber core, and the pressure within the core is equal to the ambient air pressure. These balls tend to hold their playing characteristics for a longer period of time, as it is only the cloth that deteriorates. In 1999, the International Tennis Federation (ITF) approved an experiment in which two new types of tennis ball would be permitted for use in tournaments. The two types of ball were designed to have different performance characteristics derived from their differing dynamic and aerodynamic properties. With the introduction of the two new types of tennis balls (type I and III) there are now three types of ball available for play, type I, II and III. The ball construction for all three ball types can be either pressurised or pressureless as they are classified through measurement of the diameter of the ball and a compression test, which measures the forward and return deformation of the ball under an applied load. Type 1 balls are harder than the traditional type II balls and are designed for slow pace courts such as clay. Type III balls are larger in diameter by approximately 6-8%. Research shows that they are slower through the air due to their increased drag properties, and in addition have a steeper rebound angle both giving more time for the receiver to collect the ball. Current regulations imposed by the ITF restrict the colour of the ball to yellow or white and the seams of the tennis ball must be stitchless. Strict limits are also in place for the mass and diameter for each type of tennis ball, and in addition quasi-static tests are used to determine the ball’s static stiffness and coefficient of restitution (COR) through a rebound test. Whilst these tests have the advantage of simplicity, (the rebound test was introduced in 1925 and has remained unchanged since) they may not represent how a ball performs under actual playing conditions. Incident ball speeds in the rebound test of 7m/s are far short of those found at the top echelons of the male game. Even though, as the name suggests, the ball is used primarily in tennis, it can be used as a safe substitute for games where a solid ball is necessary, for example, to replace a cricket ball, which can inflict damage or injury if not used correctly. The gift of tennis balls offered to Henry in Shakespeare's Henry V is portrayed as the final insult which re-ignites the Hundred Years War between England and France. :When we have match'd our rackets to these balls, :We will, in France, by God's grace, play a set Category:Sporting goods

Drag (physics)

:This page is about forces which tend to slow a moving object. For other uses, see Drag (disambiguation). For a solid object moving through a fluid or gas, drag is the sum of all the aerodynamic or hydrodynamic forces in the direction of the external fluid flow. It therefore acts to oppose the motion of the object, and in a powered vehicle it is overcome by thrust. Types of drag are generally divided into three categories: parasitic drag, lift-induced drag and wave drag. Parasitic drag includes form drag, skin friction and interference drag. Lift-induced drag is only relevant when wings or a lifting body are present, and is therefore usually discussed only in the aviation perspective of drag. Beyond these two kinds of drag there is a third kind of drag, called wave drag, that occurs when the solid object is moving through the fluid at or near the speed of sound in that fluid. The overall drag of an object is characterized by a dimensionless number called the drag coefficient, and is calculated using the drag equation. Assuming a constant drag coefficient, drag will vary as the square of velocity. Thus, the resultant power needed to overcome this drag will vary as the cube of velocity. The standard equation for drag is one half the coefficient of drag multiplied by the fluid density, the cross sectional area of your specified item, and the square of the velocity Wind resistance is a layman's term used to describe drag. Its use is often vague, and is usually used in a relative sense (e.g. A badminton shuttlecock has more wind resistance than a squash ball).

Momentum

:For the Sci-Fi Channel movie, see Momentum (movie) In physics, momentum is the product of the mass and velocity of an object.

Introduction - Momentum in Classical mechanics

If an object is moving in any reference frame, then it has momentum in that frame. The amount of momentum that an object has depends on two variables: the mass and the velocity of the moving object in the frame of reference. This can be written as: momentum = mass × velocity In physics, the symbol for momentum is a small p, so the above equation can be rewritten as: :

\mathbf= m \mathbf

where m is the mass and v the velocity. The SI unit of momentum is kilogram metres per second (kg m/s). The velocity of an object is given by its speed and its direction. Because momentum depends on velocity, it too has a magnitude and a direction: it is a vector quantity. For example the momentum of a 5-kg bowling ball would have to be described by the statement that it was moving westward at 2 m/s. It is insufficient to say that the ball has 10 kg m/s of momentum; the momentum of the ball is not fully described until information about its direction is given. A step change in an object's momentum is known as an impulse: The impulse (mass × change in velocity) = force applied × the time over which the force was applied. :

m \Delta \mathbf= \mathbf \Delta t

Origin of momentum

Momentum arises from the condition that an experiment must give the same results regardless of the position or relative velocity of the observer. More formally, it is the requirement of invariance under translation. Classical momentum is the result of this invariance in three dimensions. The definition of momentum was changed when Einstein formulated special relativity, so that its magnitude would remain invariant under relativistic transformations.

Conservation of momentum

Because of the way it is defined, momentum is always conserved. In the absence of external forces, a system will have constant total momentum: a property that is identical to Newton's law of inertia, his first law of motion. Newton's third law of motion, the law of reciprocal actions, dictates that the forces acting between systems are equal, which is equivalent to a statement of the conservation of momentum.

Conservation of momentum and collisions

Momentum has the special property that it is always conserved, even in collisions. Kinetic energy, on the other hand, is not conserved in collisions if they are inelastic. Since momentum is conserved it can be used to calculate unknown velocities following a collision. A common problem in physics that requires the use of this fact is the collision of two particles. Since momentum is always conserved, the sum of the momentum before the collision must equal the sum of the momentum after the collision: ::

m_1 \mathbf v_ + m_2 \mathbf v_ = m_1 \mathbf v_ + m_2 \mathbf v_ \,

:where the subscript i signifies initial, before the collision, and f signifies final, after the collision. Usually, we either only know the velocities before or after a collision and like to also find out the opposite. Correctly solving this problem means you have to know what kind of collision took place. There are two basic kinds of collisions, both of which conserve momentum:
- Elastic collisions conserve kinetic energy
- Inelastic collisions don't conserve kinetic energy

Elastic collisions

A collision between two pool or snooker balls is a good example of an almost totally elastic collision. In addition to momentum being conserved when the two balls collide, the sum of kinetic energy before a collision must equal the sum of kinetic energy after: ::

\begin\frac\end m_1  v_^2
      + \begin\frac\end m_2 v_^2
      = \begin\frac\end m_1  v_^2
      + \begin\frac\end m_2 v_^2 \,

Since the 1/2 factor is common to all the terms, it can be taken out right away.

Head-on collision (1 dimensional)

In the case of two objects colliding head on we find that the final velocity

::

v_ = \left( \frac \right) v_ + \left( \frac \right) v_ \,

v_ = \left( \frac \right) v_ + \left( \frac \right)  v_ \,

Inelastic collisions

A common example of a perfectly inelastic collision is when two objects collide and then stick together afterwards. This equation describes the conservation of momentum: ::

m_1 \mathbf v_ + m_2 \mathbf v_ = \left( m_1 + m_2 \right) \mathbf v_f \,

Changes in momentum

Although momentum is conserved within a closed system, individual parts of a system can undergo changes in momentum. In classical mechanics, an impulse changes the momentum of a body, and has the same units and dimensions as momentum. The SI unit of impulse is the same as for momentum (kg m/s). An impulse is calculated as the integral of force with respect to time. :

\mathbf = \int \mathbf\, dt

where :I is the impulse, measured in kilogram metres per second :F is the force, measured in newtons :t is the time duration, measured in seconds In the presence of a constant force, impulse is often written using the formula :

\mathbf = \mathbf\Delta t

where :

\Delta t

is the time interval over which the force (F) is applied. Using the definition of force yields: :

\mathbf = \int \frac\, dt

\mathbf = \int d\mathbf

\mathbf = \Delta \mathbf

It is therefore common to define impulse as a change in momentum.

Momentum in relativistic mechanics

Relativistic momentum as proposed by Albert Einstein arises from the invariance of four-vectors under Lorentzian translation. These four-vectors appear spontaneously in the Green's function from quantum field theory. A vector, called the Four-momentum is defined as: :[E/c p] where E is the total energy of the system, and p is called the "relativistic momentum" defined thus: :

E = \gamma mc^2 \;

\mathbf = \gamma m\mathbf

where :

\gamma = \frac

::where :::

v^2 = \mathbf v \cdot \mathbf v

. Setting velocity to zero, one derives that the rest mass and the energy of an object are related by E=mc². The "length" of the vector that remains constant is defined thus: :

\mathbf \cdot \mathbf - E^2/c^2

Massless objects such as photons also carry momentum; the formula is p=E/c, where E is the energy the photon carries and c is the speed of light. Momentum is the Noether charge of translational invariance. As such, even fields as well as other things can have momentum, not just particles. However, in curved space-time which is not asymptotically Minkowski, momentum isn't defined at all.

Momentum in quantum mechanics

In quantum mechanics momentum is defined as an operator on the wave function. The Heisenberg uncertainty principle defines limits on how accurately the momentum and position of a single observable system can be known at once. In quantum mechanics position and momentum are interchangeable. For a single particle with no electric charge and no spin, the momentum operator can be written in the position basis as :

\mathbf=\nabla=-i\hbar\nabla

where

\nabla

is the gradient operator. This is a commonly encountered form of the momentum operator, though not the most general one.

Figurative use

A process may be said to gain momentum. The terminology implies that it requires effort to start such a process, but that it is relatively easy to keep it going. Alternatively, the expression can be seen to reflect that the process is adding adherents, or general acceptance, and thus has more mass at the same velocity; hence, it gained momentum.

References

- Halliday, David; Resnick, Robert (1970). Fundamentals of Physics (2nd Ed). New York: John Wiley & Sons.
- Tipler, Paul (1998). Physics for Scientists and Engineers: Vol. 1: Mechanics, Oscillations and Waves, Thermodynamics (4th ed.). W. H. Freeman. ISBN 1572594926
- Serway, Raymond; Jewett, John (2003). Physics for Scientists and Engineers (6 ed.). Brooks Cole. ISBN 0534408427 zh-min-nan:Ūn-tōng-liōng ko:운동량 ms:Momentum ja:運動量

China

to protect the north from nomadic invaders and has been rebuilt several times since.]] China () refers to a number of states and cultures that have existed and are viewed as having succeeded one another in continental East Asia, dating back at least 3,500 years. China as it exists today has been variously described in different points of view as a single civilization or multiple civilizations, as a single state or multiple states, and as a single nation or multiple nations. With one of the world's longest periods of mostly uninterrupted civilization and the world's longest continuously used written language system, China's history has been largely characterized by repeated divisions and reunifications amid alternating periods of peace and war, and violent imperial dynastic change. The country's territorial extent expanded outwards from a core area in the North China Plain, and varied according to its moving fortunes to include multiple regions of East, Northeast, and Central Asia. For centuries, Imperial China was also one of the world's most technologically advanced civilizations, and East Asia's dominant cultural influence, with an impact lasting to the present day throughout the region. By the nineteenth and early twentieth centuries, however, China's political, economic, and military influence declined relative to growing regional power Japan and the influence of Western powers. Semi-colonialism developed by the late nineteenth century in parts of China, and the country was invaded by the Empire of Japan during World War II. The imperial system in China ended with the establishment of the Republic of China (ROC) under Sun Yat-sen in 1912; however, the next four decades of ROC rule were marred by warlord control, the Second Sino-Japanese War (WWII), and the Chinese Civil War which pitted Chinese Nationalists against the Communist forces. After its victory in the Chinese Civil War, the Communist Party of China under Mao Zedong established the People's Republic of China (PRC) in 1949, forcing the Republic of China (ROC) to retreat to the island of Taiwan, which it had governed since the end of World War II. Since then, the ROC has maintained administrative control over Taiwan, the Pescadores, several islands off the coast of Fujian province, and some islands in the South China Sea.

Terminology

"Zhongguo"

South China Sea China is called Zhongguo in Mandarin Chinese (Simplified: 中国, Traditional: 中國; also romanized as Jhongguo or Chung-kuo), which is usually translated as "Middle Kingdom", but could also be translated as "Central State" or "Central Country". Zhong (中) means "middle" or "center" while guo (国 or 國) means "country," "kingdom," "state," or "land", referring to the claim that China stood at the centre of that society's "known world", surrounded by lesser tributary states. The term has not been used consistently throughout Chinese history, however, and carries certain cultural and political connotations both positive and negative, some ideological, and early states considered part of Chinese history are not called "Zhongguo". During the Spring and Autumn Period, it was used only to describe the states politically descended from the Western Zhou Dynasty, in the Yellow River (Huang He) valley, to the exclusion of states such as Chu and Qin. The "Chinese" thus defined their nation as culturally and politically distinct from - and as the axis mundi of surrounding nations; a concept that continued well into the Qing Dynasty, although being continually redefined while the central political influence expanded territorially, and its culture assimilated alien influences. Thus Zhongguo quickly came to include areas farther south, as the cultural and political unit (not yet a "nation" or "country" in the modern sense) spread in a southerly direction, including the Yangtze River and Pearl River systems, and by the Tang Dynasty it even included "barbarian" regimes such as the Xianbei and Xiongnu. Inner Mongolia, Xinjiang, and Tibet, and the island of Taiwan, over time, came to be dominated (to a greater or lesser extent) by, or officially ruled by, imperial China, and are often included as a part of Zhongguo, though acceptance or denial of such claims remains politically controversial, especially where Zhongguo means PRC. During the Han Dynasty and before, Zhongguo had three distinctive meanings: # The area around the capital or imperial domain. The Book of Poetry explicitly gives this definition. # Territories under the direct authority of the "central" authorities. The Historical Records states: "Eight mountains are famed in the empire. Three are with the Man and Yi barbarians. Five are in Zhongguo." # The area now called the North China Plain. The Sanguo Zhi records the following monologue: "If we can lead the host of Wu and Yue (the area of southern Jiangsu and northern Zhejiang) to oppose Zhongguo, then we should break off relations with them soon." In this sense, the term is synonymous with Hua (華) and Xia (夏). During the period of division after the fall of the Han Dynasty, the term Zhongguo was subjected to transformation as a result of the surge of nomadic peoples from the northern frontier. This was doubly so after the loss of the Yellow River valley, the cradle of Chinese civilization, to these peoples. For example, the Xianbei called their Northern Wei regime Zhongguo, contrasting it with the Southern Dynasties, which they called the Yi (夷), meaning "barbarian". The southern dynasties, for their part, recently exiled from the north, called the Northern Wei Lu (虏), meaning "criminal" or "prisoner". In this way Zhongguo came to represent political legitimacy. It was used in this manner from the tenth century onwards by the competing dynasties of Liao, Jin and Song. The term Zhongguo came to be related to geographic, cultural and political identity and less to ethnic origin. The Republic of China, as it controlled mainland China, and later, the People's Republic of China, have used Zhongguo as an entity existing theoretically to mean all the territories and peoples within their political control as well as those outside of it (people in the Republic of China on Taiwan now usually use Zhongguo to refer to the PRC and use Taiwan to refer to itself). Thus it is asserted that all 56 officially recognized ethnic groups are Zhongguo ren (中國人), or Zhongguo people. Their disparate histories are collectively the history of Zhongguo.

"China"

Song in ancient times, was the imperial capital of 13 different historical dynasties (including the Han and Tang dynasties) in China.]] English and many other languages use forms of the name China (and the prefix Sino-), which is believed to have derived from the name of the Qin dynasty that first unified the country, even though it is not completely resolved and the origins are still controversial to an extent [http://www.bartleby.com/61/80/C0298000.html]. Despite the fact that the Qin dynasty was short-lived and was often regarded as overly tyrannical it unified the written language in China and gave the supreme ruler of China the title of "Emperor", hence, the subsequent Silk Road traders would identify themselves by that name. Alternate theories on the origin of the word "China" exist. In any circumstance, the word China passed through many languages along the Silk Road before it finally reached Europe and England. The Western "China", transliterated to Shina (支那) has also been used by Japanese since the nineteenth century, and has since evolved into a derogatory term in that language. The term "China" can narrowly mean China proper, or, often, China proper and Manchuria, Inner Mongolia, Tibet, and Xinjiang, a combination essentially coterminous with the 20th and 21st century political entity China; the boundaries between these regions do not necessarily follow provincial boundaries. In many contexts, "China" is commonly used to refer to the People's Republic of China or mainland China, while "Taiwan" is used to refer to the Republic of China. Informally, in economic or business contexts, "the Greater China region" (大中華地區) refers to Mainland China, Hong Kong, Macau, and Taiwan. Sinologists usually use "Chinese" in a more restricted sense, more akin to the classical usage of Zhongguo, or to the meaning of the "Han ethnic group", who make up the bulk of Mainland China. In many contexts it may be more appropriate to speak of "mainland China" (中國大陸,zhōngguó dàlù in Mandarin), especially when contrasting it with other, politically different regions like Hong Kong, Macau, and territories administered by the Republic of China (Taiwan).

History

:Main articles: History of China, History of the Republic of China (1912–1949; 1949–Present on Taiwan), History of People's Republic of China (1949–Present) History of People's Republic of China China was one of the earliest centers of human civilization. Chinese civilization was also one of the few to invent writing independently, the others being ancient Mesopotamia (Sumerians), India (Indus Valley Civilization), the Mayans, and, some hold, Ancient Egypt—though it may have been learned from the Sumerians. The first dynasty according to Chinese historical sources was the Xia Dynasty. Until scientific excavations were made at early bronze-age sites at Erlitou in Henan Province, it was difficult to separate myth from reality in regard to the existence of the Xia Dynasty. But since then, archaeologists have uncovered urban sites, bronze implements, and tombs that point to the possible existence of the Xia dynasty at the same locations cited in ancient Chinese historical texts. However, the first confirmed dynasty is the Shang, who settled along the Huang He river, dating from the 18th to the 12th centuries BC. The Shang were in turn invaded by the Zhou (12th to 5th centuries BC), whose centralized authority was slowly eroded by the ceding of state-like authority to warlords ruling small states; eventually, in the Spring and Autumn period, many strong independent states, in continuous war, paid but nominal deference to the Zhou state as the Imperial centre. They were all unified under one emperor in 221 BC by Qin Shi Huang, ushering in the Qin Dynasty, the first unified centralized Chinese state. This state, however, did not last for long, as it was way too authoritarian, destroying many sources of competition for power that were also sources of good governance and development, such as scholars and intellectuals. After the fall of authoritarian Qin Dynasty in 207 BC came the Han Dynasty which lasted until 220 AD. A period of disunion followed again. In 580, China was reunited under the Sui. Under the succeeding Tang and Song dynasties, China reached its golden age. For a long period of time, especially between the 7th and 14th centuries, China was one of the most advanced civilizations in the world in technology, literature, and art. The Song Dynasty fell to the invading Mongols in 1279. The Mongols, under Kublai Khan, established the Yuan Dynasty. A peasant named Zhu Yuanzhang overthrew the Mongols in 1368 and founded the Ming Dynasty, which lasted until 1644. After the Ming dynasty, came the Qing (Manchu) dynasty, which lasted until the overthrow of Puyi in 1911. Oftentimes regime change was violent and strongly opposed and the ruler class needed to take special measures to ensure their rule and the loyalty of the overthrown dynasty. For example, after the foreign Qing (Manchus) conquered China, because they were ever suspicious of the Han Chinese, the Qing rulers put into effect measures aimed at preventing the absorption of the Manchus into the dominant Han Chinese population. However, these restrictions proved ineffective against the assimilation of Manchus into the Chinese identity and culture. In the 18th century, China achieved a decisive technological advantage over the peoples of Central Asia, which it had been at war with for several centuries, while simultaneously falling behind Europe in that respect. This set the stage for the 19th century, in which China adopted a defensive posture against European imperialism while itself engaging in imperialistic expansion into Central Asia. See Imperialism in Asia. However the primary cause of the decline of the Chinese empire was not European and American interference, as the ethnocentric Western historians would lead many to believe. On the contrary it was a series of internal upheavals. Most prominent of these was the Taiping Civil War which lasted from 1851 to 1862. The civil war was started by an extremist believer in a school of thought partly influenced by Christianity who believed himself to be the son of God and the younger brother of Jesus. Although the imperial forces were eventually victorious, the civil war was one of the bloodiest in human history - costing at least twenty million lives (more than the total number of fatalities in the First World War). Prior to this conflict a number of Islamic Rebellions, especially in Central Asia, had occurred. Later, a second major rebellion took place, although this latter uprising was considerably smaller than the cataclysmic Taiping Civil War. This second conflict was the Boxer Rebellion which aimed to repel Westerners. Although secretly supporting the rebels, the Empress, Ci Xi, aided foreign forces in suppressing the uprising. Ci Xi, 1949.]] In 1912, after a prolonged period of decline, the institution of the Emperor of China disappeared and the Republic of China was established. The following three decades were a period of disunion — the Warlord Era, the Sino-Japanese War, and the Chinese Civil War. The latter ended in 1949 with the Communist Party of China in control of mainland China. The CPC established a communist state—the People's Republic of China—that laid claim to be the successor state of the Republic of China. Meanwhile, the disorganized and potentially corrupt ROC government of the Kuomintang fled to Taiwan, where it continued to be recognized as the legitimate government of all China by the Western bloc and the United Nations until the 1970s, when most nations and the UN switched recognition to the PRC. The United Kingdom and Portugal transferred their colonies of Hong Kong and Macau on the southern Chinese coast to the PRC in 1997 and 1999, respectively. China used in a modern context often refers to just the territory of the PRC, or to "Mainland China" (the territory of the PRC excluding Hong Kong and Macau). The PRC does not recognize the ROC, as it claims to have succeeded the ROC as the legitimate governing authority of all of China including Taiwan. On the other hand, the ROC—while never formally renouncing its earlier claims or changing official maps that show its territory as including both the modern-day PRC, Mongolia and Tibet—has moved away from this former identity representing its rule over all of China, and increasingly identifies itself as Taiwan. The PRC has historically resisted the ROC's identification of itself as Taiwan, especially in light of the movement supported by residents of Taiwan and others who advocate Taiwan's identity as an independent political entity. Significant disputes persist as to the nature and extent of China, possible Chinese reunification and the political status of Taiwan.

Chinese Pre-history

Archeological evidence suggests that the earliest occupants in China date as long as 2.24 million to 250,000 years ago by an ancient human relative (hominin) known as Homo erectus. One particular cave in Zhoukoudian (now known as Peking) has fossilised evidence dating to 300,000 and 550,000 years old. Evidence of primitive stone tool technology and animal bones in association to H. erectus have been studied since the late 18th century to 19th century in various areas of Eastern Asia including Indonesia (in particular the Island of Java) and Malaysia. Originally it is thought that these early hominis first evolved in Africa during the Pleistocene. It is thought that human evolution first took place in Africa expanding 7 million years. By 2 million years ago the first wave of migration from the species in association with H. erectus settled into various areas in the Old World. Fully modern humans (homo sapiens) are believed to originally have evolved roughly 200,000 and 168,000 years ago in Ethiopia or Southern Africa (ei. Homo sapiens idaltu). By 100,000 to 50,000 years ago modern human beings settled in all parts of the Old world (including the New World, Americas 25,000 to 11,000 BCE). By less than 100,000 years ago all proto-human populations disappeared as modern humans took over or drove other human species into extinction. It remains a controversial subject to whether fully modern humans evolved from separate H. erectus populations (known as "multiregional") as some evidence in ancient bones show a transitional change from H. erectus to H. sapiens having archaic features. However it is now more widely accepted that all modern humans genetically share a direct ancestor, a female nicknamed "Mitochondrial Eve" from Eastern Africa 150,000 years BCE. This model is known as Mitochondrial Eve Hypothesis. The earliest evidence examples of fully modern humans in China come from Liujiang, China where a cranium dates 67,000 years BCE. Another is a partial skeleton from Minatogawa being just 18,000 years old.

Political history

Before unification by the Qin Dynasty in 221 BC, "China" did not exist as a coherent entity. The Chinese civilization consisted of a patchwork of several states, each ruled by a king (王), duke (公), marquess (侯), or earl (伯). Although there was a central king who held nominal power, and powerful hegemons sometimes held considerable influence, each state was ruled as an independent political entity. This is also the time of the beginnings of Confucian philosophy and that of many other philosophies that greatly influenced Chinese philosophy-political thought. This ended with the Qin Dynasty unification, during which the office of the emperor was set up, and a system of bureaucratic administration established. After the Qin, China experienced about 13 more dynasties, many of which continued the extensive system of kingdoms, dukedoms, earldoms, and marquisates. The territory varied with several expansions and contractions depending on the strength of each emperor and dynasty. However the emperor had ultimate, supreme, and unquestionable authority as the political and religious leader of China. The emperor also consulted civil and martial ministers, especially the prime minister. Political power sometimes fell into the hands of powerful officials, eunuchs, or imperial relatives, often at the expense of a child heriditary emperor. This happened especially since the emperor often was many layers of power removed from the outside world, making him susceptible to manipulation because his sources for information could manipulate that information causing him to make incorrect decisions, especially when their age at becoming emperor often had no bottom limit, with rule passing heriditarily but also given "in trust" to another relative. Political relations with dependencies (tributary kingdoms) were maintained by international marriages, military aids, treaties, and gifts. (see section "Geography, Political" below for examples), Luoyang, Chang'an (today's Xi'an), Nanjing, and Beijing are the four cities most commonly designated as capitals of China over the course of history. Chinese was the official language, though periods of Mongol and Manchu conquest saw the arrival of Mongol and Manchu as alternate official languages. On January 1, 1912, the Republic of China (ROC) was established, signaling the end of the Manchu-dominated Qing Empire. Sun Yat-sen of the Kuomintang (KMT or Nationalist Party), was proclaimed provisional president of the republic. However, Yuan Shikai, a former Qing general who had defected to the revolutionary cause, soon forced Sun to step aside and took the presidency for himself (formally it was a negotiation where Sun agreed to step aside for what was then perceived as a strong reformer, Yuan). Before long, Yuan attempted to have himself proclaimed emperor of a new dynasty; however, he died soon of natural causes before fully taking power over all of the Chinese empire. After Yuan's downfall, China was politically fragmented, with an internationally-recognized, but virtually powerless, national government seated in Beijing (thus failing to fit the definition of a state). Warlords in various regions exercised actual control over their respective territories. state In the late 1920s, the Kuomintang, under Chiang Kai-shek, was able to reunify the country under its own control, moving the nation's capital to Nanjing and implementing "political tutelage", an intermediate stage of political development outlined in Sun Yat-sen's program for transforming China into a modern, democratic state. Effectively, political tutelage meant one-party rule by the Kuomintang with heavy Leninist influences. Ironically, both the Kuomintang and the CCP have heavy Leninist influences. In 1947, constitutional rule was established, but because of the ongoing Chinese Civil War between the Kuomintang and the Communist Party of China (CPC), many provisions of the 1947 ROC constitution were never put into actual practice on the mainland. By early 1950, the CPC had defeated the Kuomintang on the mainland, and the ROC government retreated to the island of Taiwan. Beginning in the late 1970s, Taiwan began the implementation of full, multi-party, representative democracy in the territories still under ROC control (i.e., Taiwan Province, Taipei, Kaohsiung and some offshore islands of Fujian province). Today, the political scene in the ROC is vibrant, with active participation by all sectors of society. But rather than the usual conservative-liberal policy distinctions that are the hallmarks of most democracies around the world, the main cleavage in ROC politics is the unification with China in the long-run vs. formal independence issue. However, Greens are generally more liberal (i.e. more environmentally friendly) and Blues are generally regarded as more conservative. environmentally friendly Meanwhile, Mao Zedong, the leader of the communists, proclaimed the People's Republic of China (PRC) on October 1, 1949 in Beijing, saying China had stood up. From the beginning, the PRC has been a dictatorial one-party state under the Communist Party. However, post-1978 reforms have led to the relaxation, in varying degrees, of party control over many areas of society. Nonetheless, the Communist Party still has absolute control over political aspects of society, and it continuously seeks to eradicate threats to its rule. Examples of this include the jailing of political opponents and journalists, general control of the press, regulation of religions and other non-party organizations, censorship of the press, literature and film, and suppression of independence/secessionist movements. In 1989, a popular demonstration held in Beijing at Tiananmen Square was violently put to an end by the Chinese government. Tiananmen_Square_protests_of_1989 The attempted eradication of the Falun Gong movement is also held by its supporters to be motivated by fear of Falun Gong's growing influence. Today, however, there is much more freedom in intellectual thought in non-political areas and propaganda, while still continuing, has lessened.

Territory

Historical overview

propaganda The Zhou Dynasty, which preceded the unification of China by Shi Huangdi, was originally the region around the Yellow River. Since then, the territory has expanded outward in all directions, and was largest during the Tang, Yuan, and Qing dynasties. The Qing Dynasty included parts of modern Russian Far East and Central Asia (west of Xinjiang). Xinjiang Along with provincial administrators, some foreign monarchs sent envoys to offer gifts to the Emperor of China and the Emperor returned compliments to them. The Chinese thought that the barbarians attached themselves to the virtue of the Emperor, while the foreign governments sometimes disagreed. Since the end of the 19th century, China has tried to reinterpret this relationship as suzerainty or suzerainty-dependency, but this no longer has any real conception in modern international political theories. The Qing Empire reduced the territorial value of the Great Wall of China as a barrier of China proper after they merged their homeland (Manchuria) north of the wall with China proper south of it. In 1683 after the surrender of the Kingdom of Tungning established by Koxinga, Taiwan including the Pescadores became a part of the Qing Empire, originally as one prefecture, then two, and later a province. Taiwan was subsequently ceded to Japan after the first Sino-Japanese War in 1895. At the end of the second Sino-Japanese War in 1945, Japan relinquished the sovereignty of the island in the San Francisco Peace Treaty, and the Republic of China took over. Since then, the de jure sovereignty of Taiwan has been under dispute between the PRC, and the now democratic ROC and Taiwan independence supporters.

Historical political divisions

Historically, top-level political divisions of China have altered as the administration changed. Top levels included circuits and provinces. Below that, there have been prefectures, subprefectures, departments, commanderies, districts, and counties. Recent divisions also include prefecture-level cities, county-level cities, towns and townships (see below for examples). Historically, most Chinese dynasties were based in the historical heartlands of China, known by the politically-correct term of China proper (since it doesn't include places it doesn't control, such as Mongolia or Taiwan). Various dynasties also exhibited expansionism by engaging in incursions into more peripheral territories like Inner Mongolia, Manchuria, Xinjiang, and Tibet. The Manchu-established Qing Dynasty and its successors, the Republic of China and the People's Republic of China cemented the incorporation of these territories into China. These territories are separated by borders that are vague at best, and do not correspond well to contemporary political divisions. China proper is generally thought to be bounded by the Great Wall and the edge of the Tibetan plateau; Manchuria and Inner Mongolia are found to the north of the Great Wall of China, and the boundary between them can either be taken as the present border between Inner Mongolia and the northeast Chinese provinces, or the more historic border of the World War II-era puppet state of Manchukuo; Xinjiang's borders correspond to today's administrative Xinjiang; and historic Tibet is conceived as occupying all of the Tibetan Plateau. China is also traditionally thought of as comprising North China (北方) and South China (南方), the geographic boundary between which north and south is largely generalized as Huai River (淮河) and Qinling Mountains (秦岭).

Geography and climate

Qinling Mountains

China within East Asia. ([http://www.cia.gov/cia/publications/factbook/reference_maps/pdf/asia.pdf PDF])

China is composed of a vast variety of highly different landscapes, with mostly plateaus and mountains in the west, and lower lands on the east. As a result, principal rivers flow from west to east, including the Yangtze (central), the Huang He (central-east), and the Amur (northeast), and sometimes toward the south (including the Pearl River, Mekong River, and Brahmaputra), with most Chinese rivers emptying into the Pacific. Most of China's arable lands lie along the two major rivers, the Yangtze and the Huang He, and each are the centers around which are founded China's major ancient civilizations. In the east, along the shores of the Yellow Sea and the East China Sea are found extensive and densely populated alluvial plains; the shore of the South China Sea is more mountainous and southern China is dominated by hill country and lower mountain ranges. To the west, the north has a great alluvial plain, and the south has a vast calcareous tableland traversed by hill ranges of moderate elevation, with the Himalayas, containing the highest point Mount Everest. The northwest also has high plateaus among more arid desert landscapes such as the Takla-Makan and the Gobi Desert, which has been expanding. Due to a prolonged drought and perhaps poor agricultural practices, dust storms have become usual in the spring in China. Dust blows all the way to southern China, Taiwan, and has even been measured on the West Coast of the United States. United States native to the bamboo forests of central and southern China.]] During many dynasties, the southwestern border of China has been the high mountains and deep valleys of Yunnan, which separate modern China from Burma, Laos and Vietnam. The climate of China varies greatly. The northern zone (within which lies Beijing) has a climate with winters of Arctic severity. The central zone (within which Shanghai is situated) has a generally temperate climate. The southern zone (within which lies Guangzhou and other southern provinces) has a generally subtropical climate. The Palaeozoic formations of China, excepting only the upper part of the Carboniferous system, are marine, while the Mesozoic and Tertiary deposits are estuarine and freshwater or else of terrestrial origin. Groups of volcanic cones occur in the Great Plain of north China. In the Liaodong and Shandong Peninsulas, there are basaltic plateaux.

Demographics

Shandong.]] Over a hundred ethnic groups have existed in China. In terms of numbers, however, the pre-eminent ethnic group in China is the Han, which is a group so diverse in its culture and language that some conceive of it as a larger overarching group bringing together many smaller, distinct ethnic groups sharing common traits in language and culture. Throughout history, many ethnic groups have been assimilated into neighbouring ethnicities or disappeared without a trace. Several previously distinct ethnic groups have been Sinicized into the Han, causing its population to increase dramatically; at the same time, many within the Han identity have maintained distinct linguistic and cultural traditions, though still identifying as Han. Many times in the past millenia many foreign groups have, in turn, shaped Han language and culture, for example the queue is a pig tail hairstyle strictly enforced by the Manchurians on the Han populace. The term Zhonghua Minzu is sometimes used to describe a notion of a "Chinese nationality" transcending ethnic divisions. The government of the People's Republic of China now officially recognizes a total of 56 ethnic groups, of which the largest is the Han Chinese. China's overall population is 1.3 billion. With the global human population currently estimated at about 6.4 billion, China is home to approximately 20%, or one-fifth of the human species, homo sapiens. The lack of birth control and promotion of population growth during the rule of Mao Zedong resulted in a demographic explosion, culminating in over 1.3 billion people today. As a response to the problems this is causing, the government of the PRC has enacted a birth control policy, commonly known as the One-child policy. The Han speak several mutually unintelligible tongues, classified by modern linguists as being separate languages, but regarded within the Chinese languages as "dialects" or "local languages" (topolects) within a single Chinese language (the word for "area languages" has an implication of dialect rather than a separate language, although on the basis of use, these topolects can be found to be separate and mutually unintelligible, and are so classified by many linguists). The various spoken varieties of Chinese share a common written standard, "Vernacular Chinese" or "baihua", which has been used since the early 20th Century and is based on Standard Mandarin, the standard spoken language, in grammar and vocabulary. In addition, another, more ancient written standard, Classical Chinese, was used for writing Chinese by the literati for thousands of years before the 20th Century. Classical Chinese is no longer the predominant form of written Chinese, though it continues to be a part of high school curricula and is hence intelligible to some degree to many Chinese people. Other than Standard Mandarin, spoken variants are usually not written; the exception is Standard Cantonese, which is sometimes written as Written Cantonese in informal contexts. Written Cantonese.]]

Culture

Religion

The major religions of China are:
- Taoism - exact numbers unknown
- Buddhism - exact numbers unknown [about 8%]
- Christianity - 2 to 4% (this is a Western number, the Chinese official number is much smaller than 1%)
- Islam - 1% to 2%
- Falun Gong - exact numbers unknown (claim not to be a "religion", though from a scholarly perspective is a spiritual practice, claimed numbers of followers of the Falun Dafa are also regarded as unreliable) While the People's Republic of China is officially atheist it does allow religion under strict supervision. Historically, Taoism and Buddhism has been the dominant religion of Chinese societies, and continues to be so in Chinese societies outside of direct PRC control. In recent years, Falun Gong, a spiritual practice drawing upon Buddhism and Taoism, has attracted great controversy after the government of the People's Republic of China labeled it an evil cult and began an attempt to eradicate it. The Falun Gong itself denies that it is a cult or a religion, even though there is solid evidence that determines Falun Gong as a rather" abormal" cult, several members have been seen to burn themselves alive even before the Chinese government has reacted to Falun Gong, unfortuantely, most people are oblivious of this fact and even a majority of members are oblivious to this. The Falun Gong says that it has approximately 70-100 million followers, which is a bit higher than estimates by outside groups, though exact numbers are unknown. They regularly protest against their suppression, both domestically and internationally.

Arts, scholarship, and literature

Falun Gong.]] Chinese literature has a long and prolific continuous history, in part because of the development of printmaking during the Song Dynasty. Before that, manuscripts of the Classics and religious texts (mainly Confucian, Taoist, and Buddhist) were manually written by ink brush (previously scratching shells) and distributed. Academies of scholars sponsored by the empire were formed to comment on these works in both printed and written form. Members of royalty frequently participated in these discussions. Tens of thousands of ancient written documents are still extant and more, from oracle bones to Qing edicts, are discovered each day, which had been formally ground up for use in Chinese medicine. oracle bones For centuries, opportunity for economic and social advancement in China could be provided by high performance on the imperial examinations. This led to a meritocracy, though in practice this was possible only among those who were not female or too poor to afford test preparation, as doing well still required tutorship. Nevertheless it was a system distinct from the European system of blood nobility. Imperial examinations required applicants to write essays and demonstrate mastery of the Confucian classics. Those who passed the highest level of the exam became elite scholar-officials known as jinshi, a highly esteemed socio-economic position. Chinese philosophers, writers, and poets have been, for the most part, highly respected, and played a key role in preserving and promoting the culture of the empire. Some classical scholars, however, were noted for their daring depictions of lives of the common people, often to the displeasure of authorities. (See List of Chinese authors, and List of Chinese language poets). The Chinese have created numerous musical instruments, such as the zheng, xiao, and erhu, that have spread throughout East and Southeast Asia, and especially areas under its influence. The sheng is the basis for several Western free-reed instruments. Chinese characters have had many variants and styles throughout the Chinese history, and were "simplified" in the mid-20th century on mainland China. Calligraphy is a major art-form in China, above that of painting and music. Because of its association with elite scholar-official bosses, it later on became commercialized, where works by famous artists became prized possessions. The great variation and beauty in the Chinese landscape is often the inspiration for great works of Chinese art. See Chinese painting for more details. Calligraphy, sushi, and bonsai are all millennia-old art that later spread to Japan and Korea.

Science and technology

Korea In addition to the cultural innovations mentioned above, technological inventions from China include:
- Compass
- Block Printmaking / Printing Technology
- Paper
- Asian abacus
- Gunpowder
- Crossbow
- Stirrup
- Lacquer
- Rudder
- Seismograph
- Silk
- Porcelain
- Paper money
- The Glider
- The Hot air balloon
- Fireworks
- Parachute Other areas of technological study:
- The main applications of mathematics in traditional China were architecture and geography. Pi (π) was calculated by 5th century mathematician Zu Chongzhi to the seventh digit. The decimal system was used in China as early as 14 Century BC. "Pascal's" Triangle was discovered by mathematician Liu Ju-Hsieh, long before Pascal was born.
- Studies in biology have been extensive, and historic records are consulted even today, such as pharmacopoeias of medicinal plant<

2005

2005 (MMV) is a common year starting on Saturday of the Gregorian calendar. 2005 is the World Year of Physics, the Year of the Rooster in the Chinese calendar, and the International Year of the Eucharist in Catholicism. See also Wikipedia's almanac of events for this year.

Events

January

- January 4 - Death of the Governor of Baghdad, Ali Al-Haidri, assassinated by gunmen.
- January 9 - The same storm which pounded the US earlier in the month hits England and Scandinavia, leaving 13 dead with widespread flooding and power cuts.
- January 9 - Mahmoud Abbas is elected to succeed Yasser Arafat as Palestinian Authority president in the Palestinian election.
- January 12 - Deep Impact is launched from Kennedy Space Center by a Delta 2 rocket.
- January 13 - Terrorists enter into Israel from Gaza and open fire on civilians near border, killing 6 and wounding 5 others. Hamas and Al-Aqsa Martyrs' Brigades claim joint responsibility for attack.
- January 14 - The Huygens probe lands on Titan, largest moon of Saturn.
- January 16 - Adriana Iliescu gives birth at 66, the oldest woman in the world to do so. Adriana Iliescu.]]
- January 18 - Terrorists murder 1 person and wound 8 people in Gush Katif, Israel. Hamas claims responsibility.
- January 20 - George W. Bush is inaugurated in Washington, D.C. for his second term as 43rd President of the United States.
- January 20 - Ireland completes metrication.
- January 21 - In Belize's capital city Belmopan, the unrest over the government's new taxes erupts into riots.
- January 23 - Viktor Yushchenko is sworn in as the third President of Ukraine in Kiev, Ukraine.
- January 25 - A stampede at Mandher Devi temple in Mandhradevi during a religious pilgrimage in India kills at least 215, mostly women and small children.
- January 30 - The first free Parliamentary elections in Iraq since 1958 take place.
- January 30 - A Royal Air Force C-130 Hercules transport plane crashes in Iraq, killing 10 British servicemen. Iraqi insurgents release a video claiming to have shot the aircraft down using a missile.

February

- February 6 - The New England Patriots defeat the Philadelphia Eagles 24-21 to win their third Super Bowl in four years.
- February 8 - Danish parliamentary elections continue the center-right coalition led by Prime Minister Anders Fogh Rasmussen and his Liberal Party.
- February 9 - An ETA car bomb injures 31 people at a conference centre in Madrid.
- February 10 - North Korea announces that it possesses nuclear weapons as a protection against the hostility it feels from the United States.
- February 10 - Saudi Arabia holds its first ever elections for municipal authorities, in which only men are allowed to vote.
- February 12 - Fire devastates the Windsor Building, a 32 story office block, in Madrid.
- February 14 - A massive suicide bomb blast in central Beirut kills Lebanon's former prime minister Rafik Hariri and at least 15 other people. At least 135 other people were also hurt.
- February 14 - Around 59 people are killed and 200 injured in a fire at a mosque in Tehran, Iran. Iran emissions of greenhouse gases.]]
- February 16 - The Kyoto Protocol comes into effect, without the support of the United States and Australia.
- February 16 - The National Hockey League cancels its 2004-2005 season becoming the first North American professional league to cancel a season due to a labour dispute.
- February 19 - Suicide bombers kill more than 30 people in Iraq as Shia Muslims mark Ashura, their holiest day.
- February 20 - Spanish referendum on the Treaty establishing a Constitution for Europe, passing it by a substantial margin, but on a low turnout.
- February 20 - Early Legislative elections in Portugal result in a landslide victory for José Sócrates and the Socialist Party.
- February 22 - More than 500 people are killed and over 1,000 injured after entire villages are flattened in an earthquake measuring 6.4 on the Richter scale in Zarand region of Kerman province in southern Iran.
- February 25 - The Serial Killer Dennis Rader is apprehended by Wichita Police and the FBI.
- February 25 - Terrorists murder 5 people and wound 50 people in Tel Aviv, Israel. Islamic Jihad claims responsibility for attack.
- February 26 - Hosni Mubarak the president of Egypt asks parliament to amend the constitution to allow multi-candidate presidential elections before September 2005.

March

- March 1 - The U.S. Supreme Court rules the death penalty unconstitutional for juveniles who committed their crimes under age 18.
- March 3 - At 19:17 the 3500-ton freighter, M/V Karen Danielsen, crashes into the Western bridge of the Great Belt Bridge of Denmark, 800m from Funen. All traffic across the bridge is closed, effectively separating Denmark in two.
- March 3 - Millionaire Steve Fossett breaks a world record by completing the first non-stop, non-refueled, solo flight around the world in the Virgin Atlantic GlobalFlyer.
- March 10 - Tung Chee Hwa's resignation: Tung Chee Hwa, the Chief Executive of Hong Kong, resigns.
- March 11 - In the UK, the controversial Prevention of Terrorism Act 2005 was finally given Royal Assent after one of the longest ever sittings by the House of Lords.
- March 13 - First round of Central African Republic elections.
- March 14 - The People's Republic of China ratifies an anti-secession law aimed at preventing Taiwan from declaring independence.
- March 14 - Nearly one million people gathered for an opposition rally in Beirut, a month after the death of former Prime Minister Rafik Hariri —