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Ekpyrotic universe

Ekpyrotic universe
The ekpyrotic universe, or ekpyrotic scenario, is a cosmological model of the origin and shape of the universe. The name comes from a Stoic term ekpyrosis (Ancient Greek ἐκπύρωσις ekpurōsis) meaning conflagration or in Stoic usage "conversion into fire".[1] The ekpyrotic model of the universe is an alternative to the standard cosmic inflation model for the very early universe; both models accommodate the standard Big Bang Lambda-CDM model of our universe.[2][3] The ekpyrotic model is a precursor to, and part of, some cyclic models. The ekpyrotic model came out of work by Neil Turok and Paul Steinhardt and maintains that the universe did not start in a singularity, but came about from the collision of two branes. See also[edit] Notes and references[edit] Jump up ^ 'the dissolution of the universe into fire'. Further reading[edit] P.

Ten games that make you think about life At the start of this year, we decided to come up with a list of Flash casual games with a philosophical bent. To be honest, we struggled. After days of research, we could only find a handful of games that had the thought-provoking depth we were looking for. Our list (which you can view by clicking here) was therefore only five games long. Fast forward to now, and it is remarkable how much difference a few months can make. In a wonderful twist, it seems it is the Flash gaming space - until now known more for the throwaway nature of its games rather than depth - that is leading the way in this exciting new area of gaming, as we hope the following games prove. One you have finished playing these games, check out our follow-up lists: Ten More Games That Make You Think About Life and Another 20 Games That Make You Think About Life. 1Immortall The game starts with you crash landing on a planet. 2Loved 3I Can Hold My Breath Forever 4The Company of Myself 5Coma 6Loondon 7I Wish I Were the Moon

Cosmological principle Astronomer William Keel explains: The cosmological principle is usually stated formally as 'Viewed on a sufficiently large scale, the properties of the Universe are the same for all observers.' This amounts to the strongly philosophical statement that the part of the Universe which we can see is a fair sample, and that the same physical laws apply throughout. The cosmological principle contains three implicit qualifications and two testable consequences. The second implicit qualification is that "looks the same" does not mean physical structures necessarily, but the effects of physical laws in observable phenomena. The cosmological principle is first clearly asserted in the Philosophiæ Naturalis Principia Mathematica (1687) of Isaac Newton. Implications[edit] The universe is now described as having a history, starting with the Big Bang and proceeding through distinct epochs of stellar and galaxy formation. Justification[edit] Criticism[edit] See also[edit] References[edit]

Diffeomorphism The image of a rectangular grid on a square under a diffeomorphism from the square onto itself. Definition[edit] Given two manifolds M and N, a differentiable map f : M → N is called a diffeomorphism if it is a bijection and its inverse f−1 : N → M is differentiable as well. If these functions are r times continuously differentiable, f is called a Cr-diffeomorphism). Two manifolds M and N are diffeomorphic (symbol usually being ≃) if there is a diffeomorphism f from M to N. Diffeomorphisms of subsets of manifolds[edit] Given a subset X of a manifold M and a subset Y of a manifold N, a function f : X → Y is said to be smooth if for all p in X there is a neighborhood U ⊂ M of p and a smooth function g : U → N such that the restrictions agree (note that g is an extension of f). Local description[edit] Remark 1. Then f is surjective and its satisfies thus Dfx is bijective at each point yet f is not invertible, because it fails to be injective, e.g., f(1,0) = (1,0) = f(−1,0). Remark 2. Remark 3.

Max Planck Max Karl Ernst Ludwig Planck, FRS[1] (April 23, 1858 – October 4, 1947) was a German theoretical physicist who originated quantum theory, which won him the Nobel Prize in Physics in 1918.[2] Planck made many contributions to theoretical physics, but his fame rests primarily on his role as originator of the quantum theory. This theory revolutionized human understanding of atomic and subatomic processes, just as Albert Einstein’s theory of relativity revolutionized the understanding of space and time. Together they constitute the fundamental theories of 20th-century physics. Early life and career[edit] Planck came from a traditional, intellectual family. Max Planck's signature at ten years of age. Planck was born in Kiel, Holstein, to Johann Julius Wilhelm Planck and his second wife, Emma Patzig. Planck as a young man, 1878 In 1877 he went to Berlin for a year of study with physicists Hermann von Helmholtz and Gustav Kirchhoff and mathematician Karl Weierstrass. Academic career[edit] , where .

Ultimate fate of the universe The ultimate fate of the universe is a topic in physical cosmology. Many possible fates are predicted by rival scientific theories, including futures of both finite and infinite duration. Once the notion that the universe started with a rapid inflation nicknamed the Big Bang became accepted by the majority of scientists,[1] the ultimate fate of the universe became a valid cosmological question, one depending upon the physical properties of the mass/energy in the universe, its average density, and the rate of expansion. There is a growing consensus among cosmologists that the universe is flat and will continue to expand forever.[2][3] The ultimate fate of the universe is dependent on the shape of the universe and what role dark energy will play as the universe ages. Emerging scientific basis[edit] Theory[edit] The theoretical scientific exploration of the ultimate fate of the universe became possible with Albert Einstein's 1916 theory of general relativity. Observation[edit] Big Rip[edit]

Shape of the Universe The shape of the universe is the local and global geometry of the universe, in terms of both curvature and topology (though, strictly speaking, it goes beyond both). When physicsist describe the universe as being flat or nearly flat, they're talking geometry: how space and time are warped according to general relativity. When they talk about whether it open or closed, they're referring to its topology.[1] Although the shape of the universe is still a matter of debate in physical cosmology, based on the recent Wilkinson Microwave Anisotropy Probe (WMAP) measurements "We now know that the universe is flat with only a 0.4% margin of error", according to NASA scientists. [2] Theorists have been trying to construct a formal mathematical model of the shape of the universe. Two aspects of shape[edit] The local geometry of the universe is determined by whether the density parameter Ω is greater than, less than, or equal to 1. Local geometry (spatial curvature)[edit] Global geometry[edit]

Researchers now able to stop, restart light By William J. Cromie Gazette Staff "Two years ago we slowed it down to 38 miles an hour; now we've been able to park it then bring it back up to full speed." Lene Hau isn't talking about a used motorbike, but about light – that ethereal, life-sustaining stuff that normally travels 93 million miles from the sun in about eight minutes. Less than five years ago, the speed of light was considered one of the universe's great constants. Hau, 41, a professor of physics at Harvard, admits that the famous genius would "probably be stunned" at the results of her experiments. "It's nifty to look into the chamber and see a clump of ultracold atoms floating there," Hau says. She and her team continued to tweak their system until they finally brought light to a complete stop. Inspired by Hau's success at slowing light, researchers working on a wooded hill a few miles away at the Harvard-Smithsonian Center for Astrophysics (CfA) used a similar technique to stop, then restart, a light beam.

Hindu cycle of the universe See also Hindu units of measurement. This is similar to the Cyclical Universe Theory in physical cosmology. The Big Bang is described as the birth of the universe (Brahma), the life of the universe then follows (Vishnu), and the Big Crunch would be described as the destruction of the universe (Shiva). In a number of stories from the Puranas the continual creation and destruction of the universe is equated to the outwards and inwards breaths of the gigantic cosmic Maha Vishnu. Hindu thesis of creation[edit] Initially everything was unmanifested and was one without a second . In vishnu purana ,It is stated that the purusha(GOD) manifests himself into three forms to maintain the material realm or the manifested realm . Karnodakasayi Vishnu expands himself as Garbhodakasayivisnu and enters into each universe and from Garbhodakasayivisnu originates bhrama from the naval . Hindu viewpoint of modern cosmology[edit] Even string theory finds a place in the Hindu texts. The end of the universe[edit]

Quintessence (physics) In physics, quintessence is a hypothetical form of dark energy postulated as an explanation of the observation of an accelerating rate of expansion of the Universe announced in 1998. It has been proposed by some physicists to be a fifth fundamental force. Quintessence differs from the cosmological constant explanation of dark energy in that it is dynamic, that is, it changes over time, unlike the cosmological constant which always stays constant. It is suggested that quintessence can be either attractive or repulsive depending on the ratio of its kinetic and potential energy. Specifically, it is thought that quintessence became repulsive about ten billion years ago (the universe is approximately 13.8 billion years old).[1] q, is given by the potential energy and a kinetic term: Hence, quintessence is dynamic, and generally has a density and wq parameter that varies with time. Jump up ^ Christopher Wanjek; "Quintessence, accelerating the Universe?" Ostriker JP, Steinhardt P (January 2001).

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