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Topic Review
Principle of Least Action
The principle of least action – or, more accurately, the principle of stationary action – is a variational principle that, when applied to the action of a mechanical system, can be used to obtain the equations of motion for that system. It was historically called "least" because its solution requires finding the path of motion in space that has the least value. The principle can be used to derive Newtonian, Lagrangian and Hamiltonian equations of motion, and even general relativity (see Einstein–Hilbert action). In relativity, a different action must be minimized or maximized. The classical mechanics and electromagnetic expressions are a consequence of quantum mechanics. The stationary action method helped in the development of quantum mechanics. In 1933, the physicist Paul Dirac demonstrated how this principle can be used in quantum calculations by discerning the quantum mechanical underpinning of the principle in the quantum interference of amplitudes. Subsequently Julian Schwinger and Richard Feynman independently applied this principle in quantum electrodynamics. The principle remains central in modern physics and mathematics, being applied in thermodynamics, fluid mechanics, the theory of relativity, quantum mechanics, particle physics, and string theory and is a focus of modern mathematical investigation in Morse theory. Maupertuis' principle and Hamilton's principle exemplify the principle of stationary action. The action principle is preceded by earlier ideas in optics. In Ancient Greece , Euclid wrote in his Catoptrica that, for the path of light reflecting from a mirror, the angle of incidence equals the angle of reflection. Hero of Alexandria later showed that this path was the shortest length and least time. Scholars often credit Pierre Louis Maupertuis for formulating the principle of least action because he wrote about it in 1744 and 1746. However, Leonhard Euler discussed the principle in 1744,[ and evidence shows that Gottfried Leibniz preceded both by 39 years.
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  • 29 Sep 2022
Topic Review
Barack Obama "Hope" Poster
The Barack Obama "Hope" poster is an image of US president Barack Obama designed by American artist Shepard Fairey. The image was widely described as iconic and came to represent Obama's 2008 presidential campaign. It is a stylized stencil portrait of Obama in solid red, beige and (light and dark) blue, with the word "progress", "hope", or "change" below (and other words in some versions). Fairey based the design on a photo taken by former Associated Press (AP) freelance photographer Mannie Garcia. He created the design in a day and printed it first as a street poster. It was then widely distributed—both as a digital image and other paraphernalia—during the 2008 election season, with approval from the Obama campaign. By July 2008, Sticker Robot had printed over 200,000 vinyl "Hope" stickers, 75% of which had been given away to support the cause. The image became one of the most widely recognized symbols of Obama's campaign, spawning many variations and imitations, including some commissioned by the Obama campaign. In January 2009, after Obama had won the election, Fairey's mixed-media stenciled portrait version of the image was acquired by the Smithsonian Institution for its National Portrait Gallery. Later that month, the photograph that Fairey based the poster on was identified and the AP began negotiations for compensation. Fairey sued for a declaratory judgment that his poster was a fair use of the photograph. The parties settled out of court in January 2011. In February 2012, Fairey pleaded guilty to destroying and fabricating evidence showing that he had used the photograph; in September, he was sentenced to two years of probation, 300 hours of community service, and a fine of $25,000.
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  • 29 Sep 2022
Topic Review
Proto-Hlai
Proto-Hlai is the reconstructed ancestor of the Hlai languages. Proto-Hlai reconstructions include those of Matisoff (1988), Thurgood (1991), Wu (2000), Ostapirat (2004), and Norquest (2007).
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Topic Review
Buddhism in Buryatia
Buddhism in Buryatia—a regional form of Buddhism.
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  • 28 Sep 2022
Topic Review
Morality and Religion
The intersections of morality and religion involve the relationship between religious views and morals. It is common for religions to have value frameworks regarding personal behavior meant to guide adherents in determining between right and wrong. These include the Triple Gems of Jainism, Islam's Sharia, Catholicism's Catechism, Buddhism's Eightfold Path, and Zoroastrianism's "good thoughts, good words, and good deeds" concept, among others. Various sources - such as holy books, oral and written traditions, and religious leaders - may outline and interpret these frameworks. Some religious systems share tenets with secular value-frameworks such as consequentialism, freethought, and utilitarianism. Religion and morality are not synonymous. Though religion may depend on morality, and even develop alongside morality, morality does not necessarily depend upon religion, despite some making "an almost automatic assumption" to this effect. According to The Westminster Dictionary of Christian Ethics, religion and morality "are to be defined differently and have no definitional connections with each other. Conceptually and in principle, morality and a religious value system are two distinct kinds of value systems or action guides." In the views of some, morality and religion can overlap. One definition sees morality as an active process which is, "at the very least, the effort to guide one's conduct by reason, that is, doing what there are the best reasons for doing, while giving equal consideration to the interests of all those affected by what one does." Value judgments can vary greatly between and within the teachings of various religions, past and present. People in some religious traditions, such as Christianity, may derive ideas of right and wrong from the rules and laws set forth in their respective authoritative guides and by their religious leaders. Divine Command Theory equates morality to adherence to authoritative commands in a holy book. Religions such as Buddhism and Hinduism generally draw from some of the broadest canons of religious works. Researchers have shown interest in the relationship between religion and crime and other behavior that does not adhere to contemporary laws and social norms in various countries. Studies conducted in recent years have explored these relationships, but the results have been mixed and sometimes contradictory. The ability of religious faiths to provide useful and consistent value frameworks remains a matter of some debate. Some religious commentators have asserted that one cannot lead a moral life without an absolute lawgiver as a guide. Other observers assert that moral behavior does not rely on religious tenets, and/or that moral guidelines vary over time and space rather than remain absolute, and secular commentators (such as Christopher Hitchens) point to ethical challenges within various religions that conflict with contemporary social norms.
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  • 28 Sep 2022
Topic Review
Dream Yoga
Dream yoga or Milam (Tibetan: རྨི་ལམ་རྣལ་འབྱོར་, Wylie: rmi lam rnal 'byor, THL: milam naljor; Sanskrit: स्वप्नदर्शन, svapnadarśana)—the Yoga of the Dream State—is a suite of advanced tantric sadhana of the entwined Mantrayana lineages of Dzogchen (Nyingmapa, Ngagpa, Mahasiddha, Kagyu and Bönpo). Dream yoga consists of tantric processes and techniques within the trance Bardos of Dream and Sleep (Standard Tibetan: mi-lam bardo) Six Yogas of Naropa. In the tradition of the tantra, the dream yoga method is usually passed on by a qualified teacher to his/her students after necessary initiation. Various Tibetan lamas are unanimous that it is more of a passing of an enlightened experience rather than any textual information. In a footnote on 'Zhitro' (Tibetan: zhi khro) Namdak & Dixey, et al. (2002: p. 124) identify that the 'dream body' and the 'bardo body' is the 'vision body' (Tibetan: yid lus):
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Topic Review
Hailuoto
Hailuoto (Finnish: [ˈhɑi̯ˌluo̯to]; Swedish: Karlö) is a Finnish island in the northern Baltic Sea and a municipality in Northern Ostrobothnia region. The municipality covers an area of (excluding sea areas) of which is inland water. Of all the Finnish sea islands, Hailuoto is the third largest after Fasta Åland and Kimitoön. Hailuoto lies opposite the city of Oulu in the Gulf of Bothnia. The distance between Oulu and Hailuoto is 53 kilometres (33 mi), and the sea area between them is called Luodonselkä (literally "the back of islet"). Land in the region is constantly rising due to post-glacial rebound. It is estimated that the first parts of Hailuoto appeared from the Baltic Sea about 1700 years ago. The current island of Hailuoto was formed from many smaller islands. Two large sections, Santonen and Hanhinen merged into the main island (Luoto) only about two centuries ago. The island is continuously expanding and eventually it will join with the continent. Kirkkosalmi, a wetland region between Hanhinen and Luoto is renowned for being an important bird refuge where rare bird species are observed. The theme of the coat of arms of Hailuoto describes the economy of the island municipality; the explanation of the coat of arms is "in a blue field with a silver rowlock." The coat of arms was designed by Teuvo-Pentti Pakkala and approved by the Hailuoto Municipal Council at its meeting on April 28, 1966. The Ministry of the Interior approved the use of the coat of arms on December 19 of the same year.
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Topic Review
Ex Nihilo
Ex nihilo is Latin for "out of nothing": when phrased as ex nihilo nihil fit, "nothing comes from nothing", it means that the universe was formed from eternal matter; as creatio ex nihilo, "creation out of nothing", it means that matter is not eternal but had to be created by some eternal uncaused cause, frequently defined as God. Creation ex nihilo is a theistic answer to the question of how the universe comes to exist: the Big Bang theory, by contrast, is a scientific theory; it offers no explanation of cosmic existence but only a description of the first few moments of that existence.
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  • 28 Sep 2022
Topic Review
Mettā
Mettā (Pali) or maitrī (Sanskrit) means benevolence, loving-kindness, friendliness, amity, good will, and active interest in others. It is the first of the four sublime states (Brahmavihāras) and one of the ten pāramīs of the Theravāda school of Buddhism. The cultivation of benevolence (mettā bhāvanā) is a popular form of meditation in Buddhism. It is a part of the four immeasurables in Brahmavihara (divine abidings) meditation. Metta as 'compassion meditation' is often practiced in Asia by broadcast chanting, wherein monks chant for the laity. The compassion and universal loving-kindness concept of Metta is discussed in the Metta Sutta of Buddhism, and is also found in the ancient and medieval texts of Hinduism and Jainism as Metta or Maitri. Small sample studies on the potential of loving-kindness meditation approach on patients suggest potential benefits. However, peer reviews question the quality and sample size of these studies, then suggest caution.
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  • 28 Sep 2022
Topic Review
Pashupata Shaivism
Pashupata Shaivism (Pāśupata, Sanskrit: पाशुपत) is the oldest of the major Shaivite Hindu schools. The philosophy of the Pashupata sect was systematized by Lakulīśa also called Nakulīśa) in the 2nd century A.D. The main texts of the school are Pāśupatasūtra with Kauṇḍinya's Pañcārthabhāṣya, and Gaṇakārikā with Bhāsarvajña's Ratnaṭīkā. Both texts were discovered only in the twentieth century. Prior to that, the major source of information on this sect was a chapter devoted to it in Vidyāraṇya's Sarvadarśanasaṅgraha.
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