Madam Curie research in radioactivity.

Marie Skłodowska Curie (7 November 1867 – 4 July 1934) was a Polish, French physicist ,chemist famous for her pioneering research on radioactivity. She was the first person honored with two Nobel Prizes in physics and chemistry. She was the first female professor at the University of Paris. She was the first woman to be entombed on her own merits (in 1995) in the Paris Panthéon.

She was born Maria Skłodowska in Warsaw, in Russian Poland, and lived there to age twenty-four. In 1891 she followed her older sister Bronisława to study in Paris, where she earned her higher degrees and conducted her subsequent scientific work. She shared her Nobel Prize in Physics (1903) with her husband Pierre Curie (and with Henri Becquerel). Her daughter Irène Joliot-Curie and son-in-law, Frédéric Joliot-Curie, would similarly share a Nobel Prize. She was the sole winner of the 1911 Nobel Prize in Chemistry. Curie was the first woman to win a Nobel Prize, and is the only woman to win in two fields, and the only person to win in multiple sciences.
Her achievements include a theory of radioactivity (a term that she coined), techniques for isolating radioactive isotopes, and the discovery of two elements, polonium and radium. Under her direction, the world's first studies were conducted into the treatment of neoplasms, using radioactive isotopes. She founded the Curie Institutes in Paris and Warsaw.
While an actively loyal French citizen, Skłodowska–Curie (as she styled herself) never lost her sense of Polish identity. She named the first chemical element that she discovered "polonium" (1898) for her native country. During World War I she became a member of the Committee for a Free Poland (Komitet Wolnej Polski). In 1932 she founded a Radium Institute (now the Maria Skłodowska–Curie Institute of Oncology) in her home town, Warsaw, headed by her physician-sister Bronisława.

Issac Newton working his vital role on major perspectives in specialization in many ways.

Sir Isaac Newton (4 January 1643 – 31 March 1727  25 December 1642 – 20 March 1727]) was an English physicist, mathematician, astronomer, natural philosopher, alchemist, and theologian. His monograph Philosophiæ Naturalis Principia Mathematica, published in 1687, lays the foundations for most of classical mechanics and is one of the most important scientific books ever written. In this work, Newton described universal gravitation and the three laws of motion, which dominated the scientific view of the physical universe for the next three centuries. Newton showed that the motions of objects on Earth and of celestial bodies are governed by the same set of natural laws, by demonstrating the consistency between Kepler's laws of planetary motion and his theory of gravitation; thus removing the last doubts about heliocentrism and advancing the Scientific Revolution.

Newton built the first practical reflecting telescope and developed a theory of colour based on the observation that a prism decomposes white light into the many colours that form the visible spectrum. He also formulated an empirical law of cooling and studied the speed of sound.
In mathematics, Newton shares the credit with Gottfried Leibniz for the development of differential and integral calculus. He also demonstrated the generalised binomial theorem, developed Newton's method for approximating the roots of a function, and contributed to the study of power series.
Newton was also highly religious. He was an unorthodox Christian, and during his lifetime actually wrote more on Biblical hermeneutics and occult studies than on science and mathematics, the subjects he is mainly associated with.
Newton is considered by many scholars and members of the general public to be one of the most influential people in human history.

Einstein field in the history to better place

Albert Einstein 14 March 1879 – 18 April 1955) was a German-born theoretical physicist who discovered the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics. He received the 1921 Nobel Prize in Physics "for his services to theoretical physics, and especially for his discovery of the law of the photoelectric effect".
Near the beginning of his career, Einstein thought that Newtonian mechanics was no longer enough to reconcile the laws of classical mechanics with the laws of the electromagnetic field. This led to the development of his special theory of relativity. He realized, however, that the principle of relativity could also be extended to gravitational fields, and with his subsequent theory of gravitation in 1916, he published a paper on the general theory of relativity. He continued to deal with problems of statistical mechanics and quantum theory, which led to his explanations of particle theory and the motion of molecules. He also investigated the thermal properties of light which laid the foundation of the photon theory of light. In 1917, Einstein applied the general theory of relativity to model the structure of the universe as a whole.
He was visiting the United States when Hitler came to power in 1933, and did not go back to Germany, where he had been a professor at the Berlin Academy of Sciences. He settled in the U.S., becoming a citizen in 1940. On the eve of World War II, he helped alert President Franklin D. Roosevelt that Germany might be developing an atomic weapon, and recommended that the U.S. begin similar research. Later, together with Bertrand Russell, Einstein signed the Russell–Einstein Manifesto, which highlighted the danger of nuclear weapons. Einstein taught physics at the Institute for Advanced Study at Princeton, New Jersey, until his death in 1955.

Einstein published more than 300 scientific papers along with over 150 non-scientific works.His great intelligence and originality have made the word "Einstein" synonymous with genius.

telephone inventer that communicates the world

Charles Grafton Page
American Charles Grafton Page (1812-1868) in 1837 passed an electric current through a coil of wire placed between the poles of a horseshoe magnet. He observed that connecting and disconnecting the current caused a ringing sound in the magnet. He called this effect "galvanic music."
 Innocenzo Manzetti
Innocenzo Manzetti considered the idea of a telephone as early as 1844, and may have made one in 1864, as an enhancement to an automaton built by him in 1849.

 Charles Bourseul

In 1854 Charles Bourseul, a French telegrapher, published a plan for conveying sounds and even speech by electricity in the magazine L'Illustration Paris.Bourseul's ideas were also published in Didaskalia (Frankfurt am Main) on September 28, 1854: "Suppose", he explained, “that a man speaks near a movable disc sufficiently flexible to lose none of the vibrations of the voice; that this disc alternately makes and breaks the currents from a battery: you may have at a distance another disc which will simultaneously execute the same vibrations.... It is certain that, in a more or less distant future, speech will be transmitted by electricity. I have made experiments in this direction; they are delicate and demand time and patience, but the approximations obtained promise a favourable result."
This make-or-break signaling was able to transmit tones and some vowels, but since it did not follow the analog shape of the sound wave (the contact was pure digital, on or off) it could not transmit consonants, or complex sounds. Bourseul's phrase "make and break the current" was inaccurately applied to later work by Philipp Reis who successfully transmitted faint voice sounds with unbroken current.^[3]

 Johann Philipp Reis

In 1860 Johann Philipp Reis produced a device that could transmit musical notes, indistinct speech, and occasionally distinct speech. The first sentence spoken on it was "Das Pferd frisst keinen Gurkensalat" (the horse doesn't eat cucumber salad). In the Reis transmitter, a diaphragm was attached to a needle that pressed against a metal contact. This resembled the make-or-break design of Bourseul, although Reis used the term "molecular motion" (molekulare Bewegung) to describe the contact points of his transmitter.^[4] The Reis transmitter was very difficult to operate, since the relative position of the needle and the contact were critical to the device's operation. This can be called a "telephone", since it did transmit voice sounds over distance, but was hardly a commercially practical telephone in the modern sense, as it failed to reliably transmit a good copy of any supplied sound.#
Thomas Edison tested the Reis equipment and found that "single words, uttered as in reading, speaking and the like, were perceptible indistinctly, notwithstanding here also the inflections of the voice, the modulations of interrogation, wonder, command, etc., attained distinct expression."
Prior to 1947, the Reis device was tested by the British company Standard Telephones and Cables (STC). The results also confirmed it could faintly transmit and receive speech. At the time STC was bidding for a contract with Alexander Graham Bell's American Telephone and Telegraph Company, and the results were covered up by STC's chairman Sir Frank Gill to maintain Bell's reputation.

Antonio Meucci

An early voice communicating device was invented around 1854 by Antonio Meucci, who called it a telettrofono. In 1871 Meucci filed a caveat at the US Patent Office. His caveat describes his invention, but does not mention a diaphragm, electromagnet, conversion of sound into electrical waves, conversion of electrical waves into sound, or other essential features of an electromagnetic telephone.
The first American demonstration of Meucci's invention took place in Staten Island, New York in 1854. In 1860, a description of it was reportedly published in an Italian-language New York newspaper, although no known copy of that newspaper issue or article survived to the present day. Meucci claimed to have invented a paired electro-magnetic transmitter and receiver, where the motion of a diaphragm modulated a signal in a coil by moving an electromagnet, although this was not mentioned in his 1871 U.S. patent caveat. A further discrepancy observed was that the device described in the 1871 caveat employed only a single conduction wire, with the telephone's transmitter-receivers being insulated from a 'ground return' path.
In the 1880s Meucci was credited with the early invention of inductive loading of telephone wires to increase long-distance signals. Unfortunately, serious burns from an accident, a lack of English, and poor business abilities resulted in Meucci failing to develop his inventions commercially in America. Meucci demonstrated some sort of instrument in 1849 in Havana, Cuba, but the evidence is clear that this was not an electromagnetic telephone and may have been a variant of a string telephone that used wire. Meucci has been further credited with invention of an anti-sidetone circuit. However, examination showed that his solution to sidetone was to maintain two separate telephone circuits, and thus use twice as many transmission wires. The anti-sidetone circuit later introduced by Bell Telephone instead cancelled sidetone through a feedback process.
An American District Telegraph (ADT) laboratory reportedly lost some of Meucci's working models, his wife reportedly disposed of others and Meucci, who sometimes lived on public assistance, chose not to renew his 1871 teletrofono patent caveat after 1874.
Meucci was recognized for his pioneering work on the telephone by the United States House of Representatives in 2002. The resolution stated that "if Meucci had been able to pay the $10 fee to maintain the caveat after 1874, no patent could have been issued to Bell." No such patent could have issued to Bell in March 1876. If Meucci had renewed his caveat, he would have been given an opportunity to prove to the examiner that the device described in his caveat was the electromagnetic telephone described in Bell's patent application.
The Meucci resolution by the US Congress was promptly followed by a Canada legislative motion by Canada's 37th Parliament, declaring Alexander Graham Bell as the inventor of the telephone. Others in Canada disagreed with the Congressional resolution, some of whom provided criticisms of both its accuracy and intent.

Wire inventor

Barbed wire, also known as barb wire(and frequently in dialect form spelled bob or bobbed), is a type of fencing wire constructed with sharp edges or points arranged at intervals along the strand(s). It is used to construct inexpensive fences and is used atop walls surrounding secured property. It is also a major feature of the fortifications in trench warfare (as a wire obstacle).
A person or animal trying to pass through or over barbed wire will suffer discomfort and possibly injury. Barbed wire fencing requires only fence posts, wire, and fixing devices such as staples. It is simple to construct and quick to erect, even by an unskilled person.
The first patent in the United States for barbed wire was issued in 1867 to Lucien B. Smith of Kent, Ohio, who is regarded as the inventor.Joseph F. Glidden of DeKalb, Illinois, received a patent for the modern invention in 1874 after he made his own modifications to previous versions.
Barbed wire was the first wire technology capable of restraining cattle. Wire fences were cheaper and easier to erect than their alternatives. (One such alternative was Osage orange, a thorny bush which was time-consuming to transplant and grow. The Osage orange later became a supplier of the wood used in making barbed wire fence posts.) When wire fences became widely available in the United States in the late 19th century, they made it affordable to fence much larger areas than before. They made intensive animal husbandry practical on a much larger scale.

Ancient musical formats

The earliest form of musical notation can be found in a cuneiform tablet that was created at Nippur, Iraq in about 2000 B.C. The tablet represents fragmentary instructions for performing music, that the music was composed in harmonies of thirds, and that it was written using a diatonic scale.A tablet from about 1250 B.C. shows a more developed form of notation. Although the interpretation of the notation system is still controversial, it is clear that the notation indicates the names of strings on a lyre, the tuning of which is described in other tablets. Although they were fragmentary, these tablets represent the earliest recorded melodies found anywhere in the world.

Ancient Greece

 

Photograph of the original stone at Delphi containing the second of the two hymns to Apollo. The music notation is the line of occasional symbols above the main, uninterrupted line of Greek lettering.

Ancient Greek musical notation was capable of representing pitch and note-duration, and to a limited extent, harmony. It was in use from at least the 6th century BC until approximately the 4th century AD; several complete compositions and fragments of compositions using this notation survive. The notation consists of symbols placed above text syllables. An example of a complete composition is the Seikilos epitaph, which has been variously dated between the 2nd century BC to the 1st century AD. Three hymns by Mesomedes o exist in manuscript. The Delphic Hymns, dated to the 2nd century BC, also use this notation, but they are not completely preserved. Ancient Greek notation appears to have fallen out of use around the time of the Decline of the Roman Empire.

 Byzantine Empire

 

Byzantine music notation style in a Romanian "Book of Hymns at the Lord's Resurrection", 1823

Byzantine music is vocal religious music, based on the monodic modal singing of Ancient Greece and the pre-islamic Near East. The notation developed for it is similar in principle to subsequent Western notation, in that it is ordered left to right, and separated into measures. The main difference is that notation symbols are differential rather than absolute, i.e. they indicate pitch change (rise or fall), and the musician has to deduce correctly, from the score and the note they are singing presently, which note comes next. The pitch symbols themselves resemble brush strokes and are colloquially called gántzoi ("hooks") in Modern Greek. Notes themselves are represented in written form only between measures, as an optional reminder, along with modal and tempo directions if needed. Additional signs are used to indicate embellishments and microtones (pitch changes smaller than a semitone), both essential in Byzantine chant (see Romanian anastasimatarion picture, left).
The seven standard note names in Byzantine "solfege" are: pá, vú, g^há, d^hē, ké, zō, nē, corresponding to Western re, mi, fa, sol, la, si, do. Byzantine music uses the eight natural, non-tempered scales called Ēkhoi, "sounds", exclusively, and therefore the absolute pitch of each note may slightly vary each time, depending on the particular Ēkhos used. Byzantine notation is still used in many Orthodox Churches. Better cantors can also use standard Western notation while adding non-notatable embellishment material from memory and "sliding" into the natural scales from experience.

 Persia and Arab world

In 1252, Safi al-Din al-Urmawi developed a form of musical notation, where rhythms were represented by geometric representation. Many subsequent scholars of rhythm have sought to develop graphical geometrical representations. For example, a similar geometric system was published in 1987 by Kjell Gustafson, whose method represents a rhythm as a two-dimensional graph.
 Early Europe
Scholar and music theorist Isidore of Seville, writing in the early 7th century, remarked that it was impossible to notate music. By the middle of the 9th century, however, a form of notation began to develop in monasteries in Europe for Gregorian chant, using symbols known as neumes; the earliest surviving musical notation of this type is in the Musica disciplina of Aurelian of Réôme, from about 850. There are scattered survivals from the Iberian Peninsula before this time, of a type of notation known as Visigothic neumes, but its few surviving fragments have not yet been deciphered.

 

Early Music Notation

To address the issue of exact pitch, a staff was introduced consisting originally of a single horizontal line, but this was progressively extended until a system of four parallel, horizontal lines was standardized. The vertical positions of each mark on the staff indicated which pitch or pitches it represented (pitches were derived from a musical mode. Although the four-line staff has remained in use until the present day for plainchant, for other types of music, staffs with differing numbers of lines have been used at various times and places for various instruments. The modern five-line staff was first adopted in France and became almost universal by the 16th century (although the use of staffs with other numbers of lines was still widespread well into the 17th century).
Because the neum system arose from the need to notate melodies, exact timing was initially not a particular issue because the music generally followed the natural rhythms of the Latin language. However, by the 10th century a system that represented up to four note lengths had been developed. These lengths were relative rather than absolute and depended on the duration of the neighbouring notes.Not until the 14th century did something like the present system of fixed note lengths arise. Starting in the 15th century, vertical bar lines were used to divide the staff into sections.These did not initially divide the music into measures (bars) of equal length (as most music then featured far fewer regular rhythmic patterns than in later periods), but appear to have been introduced as an aid to the eye for "lining up" notes on different staves that were played or sung at the same time.The use of regular measures (bars) became commonplace by the end of the 17th century.
The founder of what is now considered the standard music stave was Guido d'Arezzo, an Italian Benedictine monk who lived from 995–1050.Guido D'Arezzo's achievements paved the way for the modern form of written music, music books, and the modern concept of a composer.He named musical notes based on an ancient hymn dedicated to Saint John the Baptist, called Ut Queant Laxis, written by the lombard historian Paul the deacon. The first stanza is:

1. Ut queant laxis
2. resonare fibris,
3. Mira gestorum
4. famuli tuorum,
5. Solve polluti
6. labii reatum,
7. Sancte Iohannes.

Guido used the first letters of each verse to name the Solfège syllables: Ut, Re, Mi Fa, Sol, La, and Si (the exception being Si, which has the S of Sancte and the I of Iohannes—it also helps in that, if two adjacent notes had the same vowel, verbal communication errors became more likely). In the 17th century, Ut was changed in most countries except France to the easily singable, "open" syllable Do, said to have been taken from the name of the Italian theorist Giovanni Battista Doni.

Civilization in old 6th century in Mohenjadaro

Civilization :

The word civilisation comes from the Latin civilis, meaning civil, related to the Latin civis, meaning citizen, and civitas, meaning city or city-state.

 

The ancient city of Mohenjo-daro of the Ancient Indus valley civilisation, spanning India, Afghanistan and Pakistan is known to be one of the world's earliest cities.

In the sixth century, the Byzantine Emperor Justinian oversaw the consolidation of Roman civil law. The resulting collection is called the Corpus Juris Civilis. In the 11th century, professors at the University of Bologna, Western Europe's first university, rediscovered Corpus Juris Civilis, and its influence began to be felt across Western Europe. In 1388, the word civil appeared in English meaning "of or related to citizens."^[5] In 1704, civilization was used to mean "a law which makes a criminal process into a civil case." Civilisation was not used in its modern sense to mean "the opposite of barbarism" — as contrasted to civility, meaning politeness or civil virtue — until the second half of the 18th century.
According to Emile Benveniste (1954), the earlist written occurrence in English of civilisation in its modern sense may be found in Adam Ferguson's An Essay on the History of Civil Society (Edinburgh, 1767 - p. 2): "Not only the individual advances from infancy to manhood, but the species itself from rudeness to civilisation."
It should be noted that this usage incorporates the concept of superiority and maturity of "civilized" existence, as contrasted to "rudeness", which is used to denote coarseness, as in a lack of refinement or "civility."

File:Clash of Civiliations mapn2.png

Huntington's map of world civilizations (1996).

Before Benveniste's inquiries, the New English Dictionary quoted James Boswell's conversation with Samuel Johnson concerning the inclusion of Civilization in Johnson's dictionary:

On Monday, March 23 (1772), I found him busy, preparing a fourth edition of his folio Dictionary... He would not admit civilization, but only civility. With great deference to him I thought civilization, from to civilize, better in the sense opposed to barbarity than civility, as it is better to have a distinct word for each sense, than one word with two senses, which civility is, in his way of using it.

Characteristics

26th century BC Sumerian cuneiform script in Sumerian language, listing gifts to the high priestess of Adab on the occasion of her election. One of the earliest examples of human writing.

Social scientists such as V. Gordon Childe have named a number of traits that distinguish a civilization from other kinds of society.Civilizations have been distinguished by their means of subsistence, types of livelihood, settlement patterns, forms of government, social stratification, economic systems, literacy, and other cultural traits.
All human civilizations have depended on agriculture for subsistence. Growing food on farms results in a surplus of food, particularly when people use intensive agricultural techniques such as irrigation and crop rotation. Grain surpluses have been especially important because they can be stored for a long time. A surplus of food permits some people to do things besides produce food for a living: early civilizations included artisans, priests and priestesses, and other people with specialized careers. A surplus of food results in a division of labour and a more diverse range of human activity, a defining trait of civilizations.
Civilizations have distinctly different settlement patterns from other societies. The word civilization is sometimes simply defined as "'living in cities'". Non-farmers tend to gather in cities to work and to trade.
Compared with other societies, civilizations have a more complex political structure, namely the state. State societies are more stratified than other societies; there is a greater difference among the social classes. The ruling class, normally concentrated in the cities, has control over much of the surplus and exercises its will through the actions of a government or bureaucracy. Morton Fried, a conflict theorist, and Elman Service, an integration theorist, have classified human cultures based on political systems and social inequality. This system of classification contains four categories:

• Hunter-gatherer bands, which are generally egalitarian.
• Horticultural/pastoral societies in which there are generally two inherited social classes; chief and commoner.
• Highly stratified structures, or chiefdoms, with several inherited social classes: king, noble, freemen, serf and slave.
• Civilizations, with complex social hierarchies and organized, institutional governments.

Economically, civilizations display more complex patterns of ownership and exchange than less organized societies. Living in one place allows people to accumulate more personal possessions than nomadic people. Some people also acquire landed property, or private ownership of the land. Because a percentage of people in civilizations do not grow their own food, they must trade their goods and services for food in a market system, or receive food through the levy of tribute, redistributive taxation, tariffs or tithes from the food producing segment of the population. Early civilizations developed money as a medium of exchange for these increasingly complex transactions. To oversimplify, in a village the potter makes a pot for the brewer and the brewer compensates the potter by giving him a certain amount of beer. In a city, the potter may need a new roof, the roofer may need new shoes, the cobbler may need new horseshoes, the blacksmith may need a new coat, and the tanner may need a new pot. These people may not be personally acquainted with one another and their needs may not occur all at the same time. A monetary system is a way of organizing these obligations to ensure that they are fulfilled fairly.
Writing, developed first by people in Sumer, is considered a hallmark of civilization and "appears to accompany the rise of complex administrative bureaucracies or the conquest state."Traders and bureaucrats relied on writing to keep accurate records. Like money, writing was necessitated by the size of the population of a city and the complexity of its commerce among people who are not all personally acquainted with each other.
Aided by their division of labor and central government planning, civilizations have developed many other diverse cultural traits. These include organized religion, development in the arts, and countless new advances in science and technology.
Through history, successful civilizations have spread, taking over more and more territory, and assimilating more and more previously-uncivilized people. Nevertheless, some tribes or people remain uncivilized even to this day. These cultures are called by some "primitive," a term that is regarded by others as pejorative. "Primitive" implies in some way that a culture is "first" (Latin = primus), that it has not changed since the dawn of mankind, though this has been demonstrated not to be true. Specifically, as all of today's cultures are contemporaries, today's so-called primitive cultures are in no way antecedent to those we consider civilized. Many anthropologists use the term "non-literate" to describe these peoples. In the USA and Canada, where many people of such cultures were displaced by European settlers, the term "First Nations" is used. Generally, the First Nations of North America had hierarchical governments, religion, a barter system, and oral transmission of their traditions, cultures, laws, etc. Respect for the wisdom of elders and for their natural environment (7th Generation decision-making) sustained these cultures for over 10,000 years.
Civilization has been spread by colonization, invasion, religious conversion, the extension of bureaucratic control and trade, and by introducing agriculture and writing to non-literate peoples. Some non-civilized people may willingly adapt to civilized behaviour. But civilization is also spread by the technical, material and social dominance that civilization engenders.

 Cultural identity

"Civilization" can also refer to the culture of a complex society, not just the society itself. Every society, civilization or not, has a specific set of ideas and customs, and a certain set of manufactures and arts that make it unique. Civilizations tend to develop intricate cultures, including literature, professional art, architecture, organized religion, and complex customs associated with the elite.
The intricate culture associated with civilization has a tendency to spread to and influence other cultures, sometimes assimilating them into the civilization (a classic example being Chinese civilization and its influence on nearby civilizations such as Korea, Japan and Vietnam). Many civilizations are actually large cultural spheres containing many nations and regions. The civilization in which someone lives is that person's broadest cultural identity.
Many historians have focused on these broad cultural spheres and have treated civilizations as discrete units. One example is early twentieth-century philosopher Oswald Spengler ,even though he uses the German word "Kultur," "culture," for what we here call a "civilization." He said that a civilization's coherence is based on a single primary cultural symbol. Civilizations experience cycles of birth, life, decline, and death, often supplanted by a new civilization with a potent new culture, formed around a compelling new cultural symbol.
This "unified culture" concept of civilization also influenced the theories of historian Arnold J. Toynbee in the mid-twentieth century. Toynbee explored civilization processes in his multi-volume A Study of History, which traced the rise and, in most cases, the decline of 21 civilizations and five "arrested civilizations." Civilizations generally declined and fell, according to Toynbee, because of the failure of a "creative minority", through moral or religious decline, to meet some important challenge, rather than mere economic or environmental causes.
Samuel P. Huntington similarly defines a civilization as "the highest cultural grouping of people and the broadest level of cultural identity people have short of that which distinguishes humans from other species." Besides giving a definition of a civilization, Huntington has also proposed several theories about civilizations.
 Complex systems
Another group of theorists, making use of systems theory, looks at a civilization as a complex system, i.e., a framework by which a group of objects can be analyzed that work in concert to produce some result. Civilizations can be seen as networks of cities that emerge from pre-urban cultures, and are defined by the economic, political, military, diplomatic, social, and cultural interactions among them. Any organization is a complex social system, and a civilization is a large organization. Systems theory helps guard against superficial but misleading analogies in the study and description of civilizations.
Systems theorists look at many types of relations between cities, including economic relations, cultural exchanges, and political/diplomatic/military relations. These spheres often occur on different scales. For example, trade networks were, until the nineteenth century, much larger than either cultural spheres or political spheres. Extensive trade routes, including the Silk Road through Central Asia and Indian Ocean sea routes linking the Roman Empire, Persian Empire, India, and China, were well established 2000 years ago, when these civilizations scarcely shared any political, diplomatic, military, or cultural relations. The first evidence of such long distance trade is in the ancient world. During the Uruk phase Guillermo Algaze has argued that trade relations connected Egypt, Mesopotamia, Iran and Afghanistan. Resin found later in the Royal Tombs of Ur it is suggested was traded northwards from Mozambique.
Many theorists argue that the entire world has already become integrated into a single "world system", a process known as globalization. Different civilizations and societies all over the globe are economically, politically, and even culturally interdependent in many ways. There is debate over when this integration began, and what sort of integration – cultural, technological, economic, political, or military-diplomatic – is the key indicator in determining the extent of a civilization. David Wilkinson has proposed that economic and military-diplomatic integration of the Mesopotamian and Egyptian civilizations resulted in the creation of what he calls the "Central Civilization" around 1500 BC. Central Civilization later expanded to include the entire Middle East and Europe , and then expanded to a global scale with European colonization, integrating the Americas, Australia, China and Japan by the nineteenth century. According to Wilkinson, civilizations can be culturally heterogeneous, like the Central Civilization, or homogeneous, like the Japanese civilization. What Huntington calls the "clash of civilizations" might be characterized by Wilkinson as a clash of cultural spheres within a single global civilization. Others point to the Crusades as the first step in globalization. The more conventional viewpoint is that networks of societies have expanded and shrunk since ancient times, and that the current globalized economy and culture is a product of recent European colonialism.