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Dyson sphere

Dyson sphere
Dyson sphere is a hypothetical megastructure that completely encompasses a star and hence captures most or all of its power output. It was first described by Freeman Dyson. Dyson speculated that such structures would be the logical consequence of the long-term survival and escalating energy needs of a technological civilization, and proposed that searching for evidence of the existence of such structures might lead to the detection of advanced intelligent extraterrestrial life. Different types of Dyson spheres correlate with information on the Kardashev scale. Since then, other variant designs involving building an artificial structure or series of structures to encompass a star have been proposed in exploratory engineering or described in science fiction under the name "Dyson sphere". These later proposals have not been limited to solar-power stations. Origin of concept[edit] Feasibility[edit] Variants[edit] Dyson swarm[edit] A Dyson ring — the simplest form of the Dyson swarm — to scale.

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Star lifting Star lifting is any of several hypothetical processes by which a highly advanced civilization (at least Kardashev-II) could remove a substantial portion of a star's matter in a controlled manner for other uses. The term appears to have been coined by David Criswell. Stars have deep gravity wells, so the energy required for such operations is large. For example, lifting solar material from the surface of the Sun to infinity requires 2.1 × 1011 J/kg. This energy could be supplied by the star itself, collected by a Dyson sphere; using only 10% of the Sun's total power output would allow 5.9 × 1021 kilograms of matter to be lifted per year (0.0000003% of the Sun's total mass, or 8% of the Moon's mass). 11 of the Weirdest Solutions to the Fermi Paradox Most people take it for granted that we have yet to make contact with an extraterrestrial civilization. Trouble is, the numbers don’t add up. Our Galaxy is so old that every corner of it should have been visited many, many times over by now. No theory to date has satisfactorily explained away this Great Silence, so it’s time to think outside the box. Here are eleven of the weirdest solutions to the Fermi Paradox.

Alan Turing Alan Mathison Turing, OBE, FRS (/ˈtjʊərɪŋ/ TEWR-ing; 23 June 1912 – 7 June 1954) was a British mathematician, logician, cryptanalyst, philosopher, pioneering computer scientist, mathematical biologist, and marathon and ultra distance runner. He was highly influential in the development of computer science, providing a formalisation of the concepts of "algorithm" and "computation" with the Turing machine, which can be considered a model of a general purpose computer.[2][3][4] Turing is widely considered to be the father of theoretical computer science and artificial intelligence.[5] During World War II, Turing worked for the Government Code and Cypher School (GC&CS) at Bletchley Park, Britain's codebreaking centre. For a time he led Hut 8, the section responsible for German naval cryptanalysis. After the war, he worked at the National Physical Laboratory, where he designed the ACE, among the first designs for a stored-program computer. Early life and career[edit]

n-sphere In mathematics, the n-sphere is the generalization of the ordinary sphere to a n-dimensional space. For any natural number n, an n-sphere of radius r is defined as the set of points in (n + 1)-dimensional Euclidean space which are at distance r from a central point, where the radius r may be any positive real number. Thus, the n-sphere centred at the origin is defined by: It is an n-dimensional manifold in Euclidean (n + 1)-space.

Kardashev scale The Kardashev scale is a method of measuring a civilization's level of technological advancement, based on the amount of energy a civilization is able to utilize. The scale has three designated categories called Type I, II, and III. A Type I civilization uses all available resources on its home planet, Type II harnesses all the energy of its star, and Type III of its galaxy. The scale is only hypothetical, but it puts energy consumption in a cosmic perspective. It was first proposed in 1964 by the Russian astronomer Nikolai Kardashev (Kardashyov). Various extensions of the scale have been proposed since, from a wider range of power levels (types 0, IV and V) to the use of metrics other than pure power.

Stellar Death For stars less than about 25 solar masses the end of their lives is to evolve to white dwarfs after substantial mass loss. Due to atomic structure limits, all white dwarfs must mass less than the Chandrasekhar limit. If their initial mass is more than the Chandrasekhar limit, then they must lose their envelopes during their planetary nebula phase till they are below this mass limit. Asteroid Mining: The Future Is Built In Space Asteroid mining may sound like a far future technology or science fiction. However, according to the people at Planetary Resources, they believe we will soon be able to mine near Earth approaching asteroids for water and minerals. According to the Planetary Resources website there are at least 9000 near Earth asteroids presently and 1000 more being discovered every year. Exponential growth in technology and innovation could make astroid mining very likely in the near future. You may recognize a few of the names associated with Planetary Resources.

Fullerene The discovery of fullerenes greatly expanded the number of known carbon allotropes, which until recently were limited to graphite, diamond, and amorphous carbon such as soot and charcoal. Buckyballs and buckytubes have been the subject of intense research, both for their unique chemistry and for their technological applications, especially in materials science, electronics, and nanotechnology. History[edit] The icosahedral fullerene C540, another member of the family of fullerenes. Independently from Henson, in 1973 a group of scientists from the USSR, directed by Prof.

Exotic sphere In differential topology, an exotic sphere is a differentiable manifold M that is homeomorphic but not diffeomorphic to the standard Euclidean n-sphere. That is, M is a sphere from the point of view of all its topological properties, but carrying a smooth structure that is not the familiar one (hence the name "exotic"). The first exotic spheres were constructed by John Milnor (1956) in dimension n = 7 as S3-bundles over S4.

Yotta- Yotta is the largest unit prefix in the International System of Units (SI), denoting a factor of 1024 or 1000000000000000000000000. It has the unit symbol Y. The prefix name is derived from the Greek οκτώ (októ), meaning eight, because it is equal to 10008. It was added to the SI in 1991.[1] Usage examples: Stellar Evolution: Red Giants A star's evolution after the red giant phase depends on its mass. For stars greater than 1 solar mass, but less than 2 solar masses, the hydrogen burning shell eats its way outward leaving behind more helium ash. As the helium piles up, the core becomes more massive and contracts. The contraction heats the core as it becomes more dense. The density of the core increases to the point where the electrons become degenerate. The core begins to act more like a liquid than a gas, and it becomes incompressible and further contraction stops.

The Asteroid Mining Company – Mission There are near-limitless numbers of asteroids and more being discovered every year. More than 1,500 are as easy to reach as the Moon and are in similar orbits as Earth. Asteroids are filled with precious resources, everything from water to platinum. Harnessing valuable minerals from a practically infinite source will provide stability on Earth, increase humanity’s prosperity, and help establish and maintain human presence in space. Our Vision Planetary Resources is bringing the natural resources of space within humanity’s economic sphere of influence, propelling our future into the 21st century and beyond.

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