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Extraterrestrial Life
Extraterrestrial life, or alien life (colloquially, aliens), is life that originates from another world rather than on Earth. No extraterrestrial life has yet been scientifically conclusively detected. Such life might range from simple forms such as prokaryotes to Extraterrestrial intelligence, intelligent beings, possibly bringing forth civilizations that might be Kardashev scale, far more, or far less, advanced than humans. The Drake equation speculates about the existence of sapient life elsewhere in the universe. The science of extraterrestrial life is known as astrobiology. Speculation about the possibility of inhabited worlds beyond Earth dates back to antiquity. Early Christianity, Christian writers discussed the idea of a "plurality of worlds" as proposed by earlier thinkers such as Democritus; Augustine of Hippo, Augustine references Epicurus's idea of innumerable worlds "throughout the boundless immensity of space" in ''The City of God''. Pre-modern writers typicall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Life
Life, also known as biota, refers to matter that has biological processes, such as Cell signaling, signaling and self-sustaining processes. It is defined descriptively by the capacity for homeostasis, Structure#Biological, organisation, metabolism, Cell growth, growth, adaptation, response to stimulus (physiology), stimuli, and reproduction. All life over time eventually reaches a state of death, and none is Immortality, immortal. Many philosophical definitions of living systems have been proposed, such as self-organizing systems. Viruses in particular make definition difficult as they replicate only in Host (biology), host cells. Life exists all over the Earth in air, water, and soil, with many ecosystems forming the biosphere. Some of these are harsh environments occupied only by extremophiles. Life has been studied since ancient times, with theories such as Empedocles's materialism asserting that it was composed of Classical element, four eternal elements, and Aristotle's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The City Of God
''On the City of God Against the Pagans'' (), often called ''The City of God'', is a book of Christian philosophy written in Latin by Augustine of Hippo in the early 5th century AD. Augustine wrote the book to refute allegations that Christianity initiated the decline of Rome and is considered one of his seminal works, standing alongside the '' Confessions'', the '' Enchiridion'', '' On Christian Doctrine'', and '' On the Trinity''. As a work of one of the most influential Church Fathers, ''The City of God'' is a cornerstone of Western thought, expounding on many questions of theology, such as the suffering of the righteous, the existence of evil, the conflict between free will and divine omniscience, and the doctrine of original sin. Background The sack of Rome by the Visigoths in 410 left Romans in a deep state of shock, and many Romans saw it as punishment for abandoning traditional Roman religion in favor of Christianity. In response to these accusations, and in order t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Big Bang
The Big Bang is a physical theory that describes how the universe expanded from an initial state of high density and temperature. Various cosmological models based on the Big Bang concept explain a broad range of phenomena, including the abundance of light elements, the cosmic microwave background (CMB) radiation, and large-scale structure. The uniformity of the universe, known as the horizon and flatness problems, is explained through cosmic inflation: a phase of accelerated expansion during the earliest stages. A wide range of empirical evidence strongly favors the Big Bang event, which is now essentially universally accepted.: "At the same time that observations tipped the balance definitely in favor of the relativistic big-bang theory, ..." Detailed measurements of the expansion rate of the universe place the Big Bang singularity at an estimated billion years ago, which is considered the age of the universe. Extrapolating this cosmic expansion backward in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slavery
Slavery is the ownership of a person as property, especially in regards to their labour. Slavery typically involves compulsory work, with the slave's location of work and residence dictated by the party that holds them in bondage. Enslavement is the placement of a person into slavery, and the person is called a slave or an enslaved person (see ). Many historical cases of enslavement occurred as a result of breaking the law, becoming indebted, suffering a military defeat, or exploitation for cheaper labor; other forms of slavery were instituted along demographic lines such as race or sex. Slaves would be kept in bondage for life, or for a fixed period of time after which they would be granted freedom. Although slavery is usually involuntary and involves coercion, there are also cases where people voluntarily enter into slavery to pay a debt or earn money due to poverty. In the course of human history, slavery was a typical feature of civilization, and existed in most socie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Science Fiction
Science fiction (often shortened to sci-fi or abbreviated SF) is a genre of speculative fiction that deals with imaginative and futuristic concepts. These concepts may include information technology and robotics, biological manipulations, space exploration, time travel, Parallel universes in fiction, parallel universes, and extraterrestrials in fiction, extraterrestrial life. The genre often explores human responses to the consequences of projected or imagined scientific advances. Science fiction is related to fantasy (together abbreviated wikt:SF&F, SF&F), Horror fiction, horror, and superhero fiction, and it contains many #Subgenres, subgenres. The genre's precise Definitions of science fiction, definition has long been disputed among authors, critics, scholars, and readers. Major subgenres include hard science fiction, ''hard'' science fiction, which emphasizes scientific accuracy, and soft science fiction, ''soft'' science fiction, which focuses on social sciences. Other no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extraterrestrials In Fiction
An extraterrestrial or alien is a lifeform that did not originate on Earth. (The word ''extraterrestrial'' means 'outside Earth'.) Extraterrestrials are a common theme in modern science-fiction, and also appeared in much earlier works such as the second-century parody '' True History'' by Lucian of Samosata. History Antiquity The 2nd century writer of satires, Lucian, in his '' True History'' claims to have visited the Moon when his ship was sent up by a fountain, which was peopled and at war with the people of the Sun over colonisation of the Morning Star. The way people have thought about extraterrestrials is tied to the development of actual sciences. One of the first steps in the history of astronomy was to realize that the objects seen in the night sky were not gods or lights, but physical objects like Earth. This notion was followed by the one that celestial objects should be inhabited as well. However, when people thought about such extraterrestrials, they though ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Search For Extraterrestrial Intelligence
The search for extraterrestrial intelligence (usually shortened as SETI) is an expression that refers to the diverse efforts and scientific projects intended to detect extraterrestrial signals, or any evidence of intelligent life beyond Earth. Researchers use methods such as monitoring electromagnetic radiation, searching for optical signals, and investigating potential extraterrestrial artifacts for any signs of transmission from civilizations present on other planets. Some initiatives have also attempted to send messages to hypothetical alien civilizations, such as NASA's Voyager Golden Record, Golden Record. Modern SETI research began in the early 20th century after the advent of radio, expanding with projects like Project Ozma, the Wow! signal detection, and the Breakthrough Listen initiative; a $100 million, 10-year attempt to detect signals from nearby stars, announced in 2015 by Stephen Hawking and Yuri Milner. Since the 1980s, international efforts have been ongoing, wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Lakes
A volcanogenic lake is a lake formed as a result of volcanic activity. They are generally a body of water inside an inactive volcanic crater ( crater lakes) but can also be large volumes of molten lava within an active volcanic crater ( lava lakes) and waterbodies constrained by lava flows, pyroclastic flows or lahars in valley systems. The term volcanic lake is also used to describe volcanogenic lakes, although it is more commonly assigned to those inside volcanic craters. Volcanic crater lakes Lakes in calderas fill large craters formed by the collapse of a volcano during an eruption. Examples: * Crater Lake, Oregon, United States * Heaven Lake, China/North Korea * Lake Toba, Sumatra, Indonesia Lakes in maars fill small craters where an eruption deposited debris around a vent. Examples: * Lake Nyos, Northwest Region, Cameroon * Lac Pavin, Puy-de-Dôme, France * Soda Lakes, Nevada, United States Lava lakes These are some examples of rare lava lakes where molten lava in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrothermal Vent
Hydrothermal vents are fissures on the seabed from which geothermally heated water discharges. They are commonly found near volcanically active places, areas where tectonic plates are moving apart at mid-ocean ridges, ocean basins, and hotspots. The dispersal of hydrothermal fluids throughout the global ocean at active vent sites creates hydrothermal plumes. Hydrothermal deposits are rocks and mineral ore deposits formed by the action of hydrothermal vents. Hydrothermal vents exist because the Earth is both geologically active and has large amounts of water on its surface and within its crust. Under the sea, they may form features called black smokers or white smokers, which deliver a wide range of elements to the world's oceans, thus contributing to global marine biogeochemistry. Relative to the majority of the deep sea, the areas around hydrothermal vents are biologically more productive, often hosting complex communities fueled by the chemicals dissolved in the vent fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmospheric Composition
Atmospheric chemistry is a branch of atmospheric science that studies the chemistry of the Earth's atmosphere and that of other planets. This multidisciplinary approach of research draws on environmental chemistry, physics, meteorology, computer modeling, oceanography, geology and volcanology, climatology and other disciplines to understand both natural and human-induced changes in atmospheric composition. Key areas of research include the behavior of trace gasses, the formation of pollutants, and the role of aerosols and greenhouse gasses. Through a combination of observations, laboratory experiments, and computer modeling, atmospheric chemists investigate the causes and consequences of atmospheric changes. Atmospheric composition The composition and chemistry of the Earth's atmosphere is important for several reasons, but primarily because of the interactions between the atmosphere and living organisms. Natural processes such as volcano emissions, lightning and bombardmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
René Descartes
René Descartes ( , ; ; 31 March 1596 – 11 February 1650) was a French philosopher, scientist, and mathematician, widely considered a seminal figure in the emergence of modern philosophy and Modern science, science. Mathematics was paramount to his method of inquiry, and he connected the previously separate fields of geometry and algebra into analytic geometry. Descartes spent much of his working life in the Dutch Republic, initially serving the Dutch States Army, and later becoming a central intellectual of the Dutch Golden Age. Although he served a Dutch Reformed Church, Protestant state and was later counted as a Deism, deist by critics, Descartes was Roman Catholicism, Roman Catholic. Many elements of Descartes's philosophy have precedents in late Aristotelianism, the Neostoicism, revived Stoicism of the 16th century, or in earlier philosophers like Augustine of Hippo, Augustine. In his natural philosophy, he differed from the Scholasticism, schools on two major point ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nicholas Of Cusa
Nicholas of Cusa (1401 – 11 August 1464), also referred to as Nicholas of Kues and Nicolaus Cusanus (), was a German Catholic bishop and polymath active as a philosopher, theologian, jurist, mathematician, and astronomer. One of the first German proponents of Renaissance humanism, he made spiritual and political contributions to European culture. A notable example of this is his mystical or spiritual writings on "learned ignorance," as well as his participation in power struggles between Rome and the German states of the Holy Roman Empire. As papal legate to Germany from 1446, he was appointed cardinal for his merits by Pope Nicholas V in 1448 and Prince-Bishop of Brixen two years later. In 1459, he became vicar general in the Papal States. Nicholas has remained an influential figure. In 2001, the sixth centennial of his birth was celebrated on four continents and commemorated by publications on his life and work. Life Nicholas was born in Kues ( Latinized as "Cusa") in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
