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Biography
Thomas W. Campbell
Thomas Warren Campbell (December 9, 1944) is a physicist, lecturer, and author of the My Big T.O.E. (Theory of Everything) trilogy, a work that claims to unify general relativity, quantum mechanics, and metaphysics along with the origins of consciousness. The work is based on the simulation argument, which posits that reality is both virtual and subjective. Campbell agrees with other notable phi
  • 42.2K
  • 12 Dec 2022
Topic Review
Language Acquisition
Language acquisition is the process by which humans acquire the capacity to perceive and comprehend language (in other words, gain the ability to be aware of language and to understand it), as well as to produce and use words and sentences to communicate. Language acquisition involves structures, rules and representation. The capacity to successfully use language requires one to acquire a range of tools including phonology, morphology, syntax, semantics, and an extensive vocabulary. Language can be vocalized as in speech, or manual as in sign. Human language capacity is represented in the brain. Even though human language capacity is finite, one can say and understand an infinite number of sentences, which is based on a syntactic principle called recursion. Evidence suggests that every individual has three recursive mechanisms that allow sentences to go indeterminately. These three mechanisms are: relativization, complementation and coordination. There are two main guiding principles in first-language acquisition: speech perception always precedes speech production and the gradually evolving system by which a child learns a language is built up one step at a time, beginning with the distinction between individual phonemes. Linguists who are interested in child language acquisition for many years question how language is acquired, Lidz et al. states "The question of how these structures are acquired, then, is more properly understood as the question of how a learner takes the surface forms in the input and converts them into abstract linguistic rules and representations." Language acquisition usually refers to first-language acquisition, which studies infants' acquisition of their native language, whether that be spoken language or signed language as a result of prelingual deafness, though it can also refer to bilingual first language acquisition (BFLA), which refers to an infant's simultaneous acquisition of two native languages. This is distinguished from second-language acquisition, which deals with the acquisition (in both children and adults) of additional languages. In addition to speech, reading and writing a language with an entirely different script compounds the complexities of true foreign language literacy. Language acquisition is one of the quintessential human traits, because non-humans do not communicate by using language.
  • 42.0K
  • 18 Nov 2022
Topic Review
Quetzalcoatl
Quetzalcoatl (/ˌkɛtsɑːlkoʊˈɑːtəl/; Spanish: [ket͡salˈkoatʊl] (listen); Template:Lang-nci-IPA, in honorific form: Quetzalcohuātzin, modern Nahuatl pronunciation (help·info)) is a deity in Mesoamerican culture and literature whose name comes from the Nahuatl language and means "feathered serpent" or "Quetzal-feathered Serpent". The earliest known documentation of the worship of a Feathered Serpent occurs in Teotihuacan in the first century BC or first century AD. That period lies within the Late Preclassic to Early Classic period (400 BC – 600 AD) of Mesoamerican chronology; veneration of the figure appears to have spread throughout Mesoamerica by the Late Classic period (600–900 AD). In the Postclassic period (900–1519 AD), the worship of the feathered-serpent deity centred in the primary Mexican religious center of Cholula. In this period the deity is known to have been named "Quetzalcoatl" by his Nahua followers. In the Maya area he was approximately equivalent to Kukulkan and Gukumatz, names that also roughly translate as "feathered serpent" in different Mayan languages. Quetzalcoatl, the Aztec god of wind, air, and learning, wears around his neck the "wind breastplate" ehecailacocozcatl, "the spirally voluted wind jewel" made of a conch shell. This talisman was a conch shell cut at the cross-section and was likely worn as a necklace by religious rulers, as such objects have been discovered in burials in archaeological sites throughout Mesoamerica, and potentially symbolized patterns witnessed in hurricanes, dust devils, seashells, and whirlpools, which were elemental forces that had significance in Aztec mythology. Codex drawings pictured both Quetzalcoatl and Xolotl wearing an ehecailacocozcatl around the neck. Additionally, at least one major cache of offerings includes knives and idols adorned with the symbols of more than one god, some of which were adorned with wind jewels. In the era following the 16th-century Spanish conquest of the Aztec Empire, a number of records conflated Quetzalcoatl with Ce Acatl Topiltzin, a ruler of the mythico-historic city of Tollan. Historians debate to what degree, or whether at all, these narratives about this legendary Toltec ruler describe historical events. Furthermore, early Spanish sources written by clerics tend to identify the god-ruler Quetzalcoatl of these narratives with either Hernán Cortés or Thomas the Apostle— identifications which have also become sources of a diversity of opinions about the nature of Quetzalcoatl. Among the Aztecs, whose beliefs are the best-documented in the historical sources, Quetzalcoatl was related to gods of the wind, of the planet Venus, of the dawn, of merchants and of arts, crafts and knowledge. He was also the patron god of the Aztec priesthood, of learning and knowledge. Quetzalcoatl was one of several important gods in the Aztec pantheon, along with the gods Tlaloc, Tezcatlipoca and Huitzilopochtli. Two other gods represented by the planet Venus are Quetzalcoatl's ally Tlaloc (the god of rain), and Quetzalcoatl's twin and psychopomp, Xolotl. Animals thought to represent Quetzalcoatl include resplendent quetzals, rattlesnakes (coatl meaning "serpent" in Nahuatl), crows, and macaws. In his form as Ehecatl he is the wind, and is represented by spider monkeys, ducks, and the wind itself. In his form as the morning star, Venus, he is also depicted as a harpy eagle. In Mazatec legends the astrologer deity Tlahuizcalpantecuhtli, who is also represented by Venus, bears a close relationship with Quetzalcoatl.
  • 41.3K
  • 11 Oct 2022
Topic Review
Tears in Rain Monologue
"Tears in rain" (also known as the "C-Beams Speech") is a monologue delivered by character Roy Batty (portrayed by Rutger Hauer) in the 1982 Ridley Scott film Blade Runner. Written by David Peoples and altered by Hauer from the scripted lines the night before filming, the monologue is frequently quoted; critic Mark Rowlands described it as "perhaps the most moving death soliloquy in cinematic history". The speech appears as the last track on the film's soundtrack album.
  • 40.7K
  • 03 Nov 2022
Topic Review
Space Vector PWM Techniques
This entry elaborates the basic concept of space vector Pulse Width modulation technique for a three-phase voltage source inverter. Why space vector Pulse width modulation (PWM) is required and how it is implemented in the simulation model, is described in the entry.  A number of PWM scheme is used to obtain variable voltage and frequency supply from a power converter. The most widely used PWM schemes for three-phase voltage source inverter (VSI) are carrier-based sinusoidal PWM and space vector PWM (SVPWM). There is an increasing trend of using space vector PWM (SVPWM) because of their easier digital realization and better dc bus utilization. This entry focuses on step by step development of MATLAB/SIMULINK model of SVPWM. Firstly the model of a three-phase VSI is discussed based on space vector representation. Next simulation model of SVPWM is obtained using MATLAB/SIMULINK. Simulation results are also provided. 
  • 40.0K
  • 16 Jun 2022
Topic Review
Fatawa 'Alamgiri
Fatawa 'Alamgiri, also known as Al-Fatawa al-'Alamgiriyya (Arabic: الفتاوى العالمگيرية) or Al-Fatawa al-Hindiyya (Arabic: الفتاوى الهندية), is a 17th-century sharia based compilation on statecraft, general ethics, military strategy, economic policy, justice and punishment, that served as the law and principal regulating body of the Mughal Empire, during the reign of the Mughal emperor Muhammad Muhiuddin Aurangzeb Alamgir. It subsequently went on to become the reference legal text to enforce Sharia in colonial south Asia in the 18th century through early 20th century, and has been heralded as "the greatest digest of Muslim law made in India ".
  • 39.7K
  • 01 Dec 2022
Topic Review
Arginine Signaling and Cancer Metabolism
Arginine is an amino acid critically involved in multiple cellular processes including the syntheses of nitric oxide and polyamine, and is a direct activator of mTOR, a nutrient sensing kinase strongly implicated in carcinogenesis. In this review, we will discuss arginine as a signaling metabolite, arginine’s role in cancer metabolism, arginine as an epigenetic regulator, arginine as an immunomodulator, and arginine as a therapeutic target. The different cell killing mechanisms associated with various cancer types will also be described.
  • 38.9K
  • 23 Feb 2023
Topic Review
Temperate Climate
In geography, the temperate or tepid climates of Earth occur in the middle latitudes, which span between the tropics and the polar regions of Earth. In most climate classifications, temperate climates refer to the climate zone between 35 and 50 north and south latitudes (between the subarctic and subtropical climates). These zones generally have wider temperature ranges throughout the year and more distinct seasonal changes compared to tropical climates, where such variations are often small. They typically feature four distinct seasons, Summer the warmest, Autumn the transitioning season to Winter, the colder season, and Spring the transitioning season from winter back into summer. In the northern hemisphere, the year starts with winter, transitions in the first half year through spring into summer, which is in mid-year, then at the second half year through autumn into winter at year-end. In the southern hemisphere, the seasons are swapped, with summer between years and winter in mid-year. The temperate zones (latitudes from 23.5° to the polar circles at about 66.5°, north and south) are where the widest seasonal changes occur, with most climates found in it having some influence from both the tropics and the poles. The subtropics (latitudes from about 23.5° to 35°, north and south) have temperate climates that have the least seasonal change and the warmest in winter, while at the other end, Boreal climates located from 55 to 65 north latitude have the most seasonal changes and long and severe winters. In temperate climates, not only do latitudinal positions influence temperature changes, but sea currents, prevailing wind direction, continentality (how large a landmass is), and altitude also shape temperate climates. The Köppen climate classification defines a climate as "temperate" when the mean temperature is above −3 °C (26.6 °F) but below 18 °C (64.4 °F) in the coldest month. However, other climate classifications set the minimum at 0 °C (32.0 °F).
  • 38.5K
  • 08 Nov 2022
Topic Review
Blockchain Oracle Problem
The Blockchain Oracle Problem refers to the inability of confirming the veracity of the data collected by oracles. Also, depending on the type, the chances of malfunction, and deliberate tampering. 
  • 38.4K
  • 08 Oct 2025
Topic Review
Iman (Concept)
Iman (إِيمَان ʾīmān, lit. faith or belief) in Islamic theology denotes a believer's faith in the metaphysical aspects of Islam. Its most simple definition is the belief in the six articles of faith, known as arkān al-īmān. The term iman has been delineated in both the Quran and the Hadith of Prophet Muhammad (SAW). According to the Quran, iman must be accompanied by righteous deeds and the two together are necessary for entry into Paradise. In the Hadith of Prophet Muhammad (SAW), iman in addition to Islam and ihsan form the three dimensions of the Islamic religion. There exists a debate both within and outside Islam on the link between faith and reason in religion, and the relative importance of either. Several scholars contend that faith and reason spring from the same source and hence must be harmonious.
  • 37.9K
  • 08 Jul 2023
Topic Review
Luciferianism
Luciferianism is a belief system that venerates the essential characteristics that are affixed to Lucifer, the name of various mythological and religious figures associated with the planet Venus. The tradition, influenced by Gnosticism, usually reveres Lucifer not as the devil, but as a destroyer, a guardian, liberator, light bringer or guiding spirit to darkness, or even the true god as opposed to Jehovah.
  • 37.1K
  • 01 Dec 2022
Topic Review
History of the Middle East
Home to the Cradle of Civilization, the Middle East (usually interchangeable with the Near East) has seen many of the world's oldest cultures and civilizations. This history started from the earliest human settlements, continuing through several major pre- and post-Islamic Empires through to the nation-states of the Middle East today. Template:Human history Egyptian civilization coalesced around 3150 BC with the political unification of Upper and Lower Egypt under the first pharaoh. Mesopotamia was home to several powerful empires that came to rule almost the entire Middle East—particularly the Assyrian Empires of 1365–1076 BC and the Neo-Assyrian Empire of 911–609 BC. From the early 7th century BC and onwards, the Iranian Medes followed by Achaemenid Persia and other subsequent Iranian states empires dominated the region. In the 1st century BC, the expanding Roman Republic absorbed the whole Eastern Mediterranean, which included much of the Near East. The Eastern Roman Empire, today commonly known as the Byzantine Empire, ruling from the Balkans to the Euphrates, became increasingly defined by and dogmatic about Christianity, gradually creating religious rifts between the doctrines dictated by the establishment in Constantinople and believers in many parts of the Middle East. From the 3rd up to the course of the 7th century AD, the entire Middle East was dominated by the Byzantines and Sassanid Persia. From the 7th century, a new power was rising in the Middle East, that of Islam. The dominance of the Arabs came to a sudden end in the mid-11th century with the arrival of the Seljuq Turks. In the early 13th century, a new wave of invaders, the armies of the Mongol Empire, mainly Turkic, swept through the region. By the early 15th century, a new power had arisen in western Anatolia, the Ottoman emirs, linguistically Turkic and religiously Islamic, who in 1453 captured the Christian Byzantine capital of Constantinople and made themselves sultans. Large parts of the Middle East became a warground between the Ottomans and Iranian Safavids for centuries starting in the early 16th century. By 1700, the Ottomans had been driven out of Hungary and the balance of power along the frontier had shifted decisively in favor of the West. The British also established effective control of the Persian Gulf, and the French extended their influence into Lebanon and Syria. In 1912, the Italians seized Libya and the Dodecanese islands, just off the coast of the Ottoman heartland of Anatolia. In the late 19th and early 20th centuries, Middle Eastern rulers tried to modernize their states to compete more effectively with the European powers. A turning point in the history of the Middle East came when oil was discovered, first in Persia in 1908 and later in Saudi Arabia (in 1938) and the other Persian Gulf states, and also in Libya and Algeria. A Western dependence on Middle Eastern oil and the decline of British influence led to a growing American interest in the region. During the 1920s, 1930s, and 1940s, Syria and Egypt made moves towards independence. The British, the French, and the Soviets departed from many parts of the Middle East during and after World War II (1939–1945). The struggle between the Arabs and the Jews in Palestine culminated in the 1947 United Nations plan to partition Palestine. Later in the midst of Cold War tensions, the Arabic-speaking countries of Western Asia and Northern Africa saw the rise of pan-Arabism. The departure of the European powers from direct control of the region, the establishment of Israel, and the increasing importance of the oil industry, marked the creation of the modern Middle East. In most Middle Eastern countries, the growth of market economies was inhibited by political restrictions, corruption and cronyism, overspending on arms and prestige projects, and over-dependence on oil revenues. The wealthiest economies in the region per capita are the small oil-rich countries of Persian Gulf: Qatar, Kuwait, Bahrain, and the United Arab Emirates. A combination of factors—among them the 1967 Six-Day War, the 1970s energy crisis beginning with the 1973 OPEC oil embargo in response to U.S. support of Israel in the Yom Kippur War, the concurrent Saudi-led popularization of Salafism/Wahhabism, and the 1978-79 Iranian Revolution—promoted the increasing rise of Islamism and the ongoing Islamic revival (Tajdid). The Fall of the Soviet Union in 1991 brought a global security refocus from the Cold War to a War on Terror. Starting in the early 2010s, a revolutionary wave popularly known as the Arab Spring brought major protests, uprisings, and revolutions to several Middle Eastern and Maghreb countries. Clashes in western Iraq on 30 December 2013 were preliminary to the Sunni pan-Islamist ISIL uprising. The term Near East can be used interchangeably with Middle East, but in a different context, especially when discussing ancient times, it may have a limited meaning, namely the northern, historically Aramaic-speaking Semitic area and adjacent Anatolian territories, marked in the two maps below.
  • 37.0K
  • 27 Oct 2022
Topic Review
Early World Maps
The earliest known world maps date to classical antiquity, the oldest examples of the 6th to 5th centuries BCE still based on the flat Earth paradigm. World maps assuming a spherical Earth first appear in the Hellenistic period. The developments of Greek geography during this time, notably by Eratosthenes and Posidonius culminated in the Roman era, with Ptolemy's world map (2nd century CE), which would remain authoritative throughout the Middle Ages. Since Ptolemy, knowledge of the approximate size of the globe allowed cartographers to estimate the extent of their geographical knowledge, and to indicate parts of the globe known to exist but not yet explored as terra incognita. With the Age of Discovery, during the 15th to 18th centuries, world maps became increasingly accurate; exploration of Antarctica and the interior of Africa by western mapmakers was left to the 19th and early 20th century.
  • 36.5K
  • 28 Oct 2022
Topic Review
Mongol Conquest of Khwarezmia
The Mongol conquest of Khwarezmia (Persian: حمله مغول به خوارزم‎), or the Mongol invasion of Iran (Persia) (Persian: حمله مغول به ایران‎), from 1219 to 1221 marked the beginning of the Mongol conquest of the Islamic states. The Mongol expansion would ultimately culminate in the conquest of virtually all of Asia as well as parts of Eastern Europe, with the exception of Japan , the Mamluk Sultanate of Egypt, Siberia, and most of the Indian subcontinent and Southeast Asia. According to the Persian historian Minhaj-i-Siraj, Genghis Khan sent the ruler of the Khwarazmian Empire, Muhammad II, a message seeking trade and greeted him as his neighbor: "I am master of the lands of the rising sun while you rule those of the setting sun. Let us conclude a firm treaty of friendship and peace", or he said "I am Khan of the lands of the rising sun while you are sultan of those of the setting sun: Let us conclude a firm agreement of friendship and peace." The Mongols' original unification of all "people in felt tents", unifying the nomadic tribes in Mongolia and then the Turkomans and other nomadic peoples, had come with relatively little bloodshed, and almost no material loss. The Mongol wars with the Jurchens was known to Muhammad II and he agreed to this peace treaty. War between the Mongols and the Khwarazmian Empire started less than a year later, when a Mongol caravan and its envoys were massacred in the Khwarazmian city of Otrar. In the ensuing war, lasting less than two years, the Khwarazmian dynasty was destroyed and the Khwarazmian Empire was conquered.
  • 36.3K
  • 16 Nov 2022
Topic Review
The Inventions from India
India, with its history and diversity of culture, has been a significant cradle of innovation and invention in humankind for centuries. From ancient times to the present, Indian inventors and intellectuals have contributed much to mathematics, astronomy, medicine, technology and games.
  • 35.9K
  • 31 Oct 2024
Topic Review
Agency (Sociology)
In sociology, the concept of agency refers to the capacity of individuals to act independently and make choices that shape their lives and the social structures around them. Agency emphasizes the idea that individuals are not merely passive recipients of societal influences or structural forces but are active participants who can exercise their will, make decisions, and initiate actions.
  • 34.9K
  • 25 Jan 2024
Topic Review
List of Qualcomm Snapdragon Systems-on-chip
This is a list of Qualcomm Snapdragon chips. Snapdragon is a family of mobile system on a chip (SoC) made by Qualcomm for use in smartphones, tablets, laptops, 2-in-1 PCs, smartwatches , and smartbooks devices.
  • 34.9K
  • 19 Oct 2022
Topic Review
Grid Reference System
A grid reference system, also known as grid reference or grid system, is a geographic coordinate system that defines locations in maps using Cartesian coordinates based on a particular map projection. Grid lines on maps illustrate the underlying coordinate system. Such coordinate lines are numbered to provide a unique reference to each location on the map. Grid coordinates are normally eastings and northings.
  • 34.5K
  • 25 Oct 2022
Topic Review
Low-Level Equilibrium Trap
The low-level equilibrium trap is a concept in economics developed by Richard R. Nelson, in which at low levels of per capita income people are too poor to save and invest much, and this low level of investment results in low rate of growth in national income. As per capita income rises above a certain minimum level at which there is zero saving, a rising proportion of income will be saved and invested and this will lead to higher rate of growth in income.
  • 34.5K
  • 29 Nov 2022
Topic Review
List of Long Marriages
This is a list of long marriages. It includes people who have been married for at least 80 years. The length of marriage is based on the reported death of either member, or reported divorce, or the most recent report that both members of the couple were still living.
  • 34.4K
  • 07 Nov 2022
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