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Membrane (M-theory)

Membrane (M-theory)
In string theory and related theories, D-branes are an important class of branes that arise when one considers open strings. As an open string propagates through spacetime, its endpoints are required to lie on a D-brane. The letter "D" in D-brane refers to the fact that we impose a certain mathematical condition on the system known as the Dirichlet boundary condition. The study of D-branes has led to important results, such as the anti-de Sitter/conformal field theory correspondence, which has shed light on many problems in quantum field theory. See also[edit] References[edit] Jump up ^ Moore, Gregory (2005).

Metaverse The Metaverse is a collective virtual shared space, created by the convergence of virtually enhanced physical reality and physically persistent virtual space,[1] including the sum of all virtual worlds, augmented reality, and the internet. The word metaverse is a portmanteau of the prefix "meta" (meaning "beyond") and "universe" and is typically used to describe the concept of a future iteration of the internet, made up of persistent, shared, 3D virtual spaces linked into a perceived virtual universe.[2] Developing technical standards for the Metaverse[edit] Conceptually, the Metaverse describes a future internet of persistent, shared, 3D virtual spaces linked into a perceived virtual universe,[2] but common standards, interfaces, and communication protocols between and among virtual environment systems are still in development. Many of these working groups are still in the process of publishing drafts and determining open standards for interoperability. [edit] [edit] See also[edit]

Ultrafinitism In the philosophy of mathematics, ultrafinitism, also known as ultraintuitionism, strict-finitism, actualism, and strong-finitism is a form of finitism. There are various philosophies of mathematics which are called ultrafinitism. A major identifying property common among most of these philosophies is their objections to totality of number theoretic functions like exponentiation over natural numbers. Main ideas[edit] Like other strict finitists, ultrafinitists deny the existence of the infinite set N of natural numbers, on the grounds that it can never be completed. In addition, some ultrafinitists are concerned with acceptance of objects in mathematics which no one can construct in practice because of physical restrictions in constructing large finite mathematical objects. The reason is that nobody has yet calculated what natural number is the floor of this real number, and it may not even be physically possible to do so. times to 0. People associated with ultrafinitism[edit] Notes[edit]

Infinity The ∞ symbol in several typefaces History[edit] Ancient cultures had various ideas about the nature of infinity. The ancient Indians and Greeks did not define infinity in precise formalism as does modern mathematics, and instead approached infinity as a philosophical concept. Early Greek[edit] In accordance with the traditional view of Aristotle, the Hellenistic Greeks generally preferred to distinguish the potential infinity from the actual infinity; for example, instead of saying that there are an infinity of primes, Euclid prefers instead to say that there are more prime numbers than contained in any given collection of prime numbers (Elements, Book IX, Proposition 20). However, recent readings of the Archimedes Palimpsest have hinted that Archimedes at least had an intuition about actual infinite quantities. Early Indian[edit] The Indian mathematical text Surya Prajnapti (c. 3rd–4th century BCE) classifies all numbers into three sets: enumerable, innumerable, and infinite. . factors. and

Infinity (philosophy) The Isha Upanishad of the Yajurveda (c. 4th to 3rd century BC) states that "if you remove a part from infinity or add a part to infinity, still what remains is infinity". The Jain mathematical text Surya Prajnapti (c. 400 BC) classifies all numbers into three sets: enumerable, innumerable, and infinite. Each of these was further subdivided into three orders: Enumerable: lowest, intermediate and highestInnumerable: nearly innumerable, truly innumerable and innumerably innumerableInfinite: nearly infinite, truly infinite, infinitely infinite The Jains were the first to discard the idea that all infinites were the same or equal. According to Singh (1987), Joseph (2000) and Agrawal (2000), the highest enumerable number N of the Jains corresponds to the modern concept of aleph-null (the cardinal number of the infinite set of integers 1, 2, ...), the smallest cardinal transfinite number. In the Jaina work on the theory of sets, two basic types of infinite numbers are distinguished. ... ...

List of paradoxes This is a list of paradoxes, grouped thematically. The grouping is approximate, as paradoxes may fit into more than one category. Because of varying definitions of the term paradox, some of the following are not considered to be paradoxes by everyone. Although considered paradoxes, some of these are based on fallacious reasoning, or incomplete/faulty analysis. Logic[edit] Self-reference[edit] These paradoxes have in common a contradiction arising from self-reference. Barber paradox: A barber (who is a man) shaves all and only those men who do not shave themselves. Vagueness[edit] Ship of Theseus (a.k.a. Mathematics[edit] Statistics[edit] Probability[edit] Infinity and infinitesimals[edit] Benardete's paradox: Apparently, a man can be "forced to stay where he is by the mere unfulfilled intentions of the gods".Ross–Littlewood paradox: After alternatively adding and removing balls to a vase infinitely often, how many balls remain? Geometry and topology[edit]

Multiverse (religion) In religion a multiverse is the concept of a plurality of universes. Some religious cosmologies propose that the cosmos is not the only one that exists. The concept of infinite worlds is mentioned in the Apannaka Jataka: "Disciples," the Buddha said "nowhere between the lowest of hells below and the highest heaven above, nowhere in all the infinite worlds that stretch right and left, is there the equal, much less the superior, of a Buddha. Incalculable is the excellence which springs from obeying the Precepts and from other virtuous conduct." - Apannaka Jataka The concept of multiple universes is mentioned many times in Hindu Puranic literature, such as in the Bhagavata Purana: Every universe is covered by seven layers — earth, water, fire, air, sky, the total energy and false ego — each ten times greater than the previous one. The number of universes seems to be uncountable according to the Puranic literature: Analogies to describe multiple universes also exist in the Puranic literature:

The All The universe understood in relation to the All[edit] The following is commentary on possibilities about The All but not anything necessarily accepted by Hermeticists in general. According to The Kybalion, The All is a bit more complicated than simply being the sum total of the universe. Rather than The All being simply the physical universe, it is more correct to say that everything in the universe is within the mind of The All, since the ALL can be looked at as Mind itself.[3] In effect, the universe is partially existent on the Mental plane, and we may in fact all be parts of The All's psychological makeup, representing parts of The All in its dream or meditation. The Three Initiates (see The Kybalion) strongly caution that we restrain from simply declaring "I am God" for oversimplification purposes. Because of this view, some Hermetics also practice theurgy. Explaining why The All acts[edit] Questions as to why God acts or doesn't act is an ancient question with many divergent answers.

Buddhist cosmology Buddhist cosmology is the description of the shape and evolution of the Universe according to the Buddhist scriptures and commentaries. Introduction[edit] The self-consistent Buddhist cosmology which is presented in commentaries and works of Abhidharma in both Theravāda (31 planes, Sakwala Vibhanga) and Mahāyāna traditions, is the end-product of an analysis and reconciliation of cosmological comments found in the Buddhist sūtra and vinaya traditions. No single sūtra sets out the entire structure of the universe. Buddhist cosmology can be divided into two related kinds: spatial cosmology, which describes the arrangement of the various worlds within the universe, and temporal cosmology, which describes how those worlds come into existence, and how they pass away. Spatial cosmology[edit] Spatial cosmology can also be divided into two branches. Vertical cosmology[edit] Formless Realm (Ārūpyadhātu)[edit] There are four types of Ārūpyadhātu devas, corresponding to the four types of arūpadhyānas:

Hindu cosmology In Hindu cosmology the universe is cyclically created and destroyed. The Hindu literature, such as Vedas, Puranas, cites the creation of universe. They describe the aspects of evolution, astronomy, etc. Description[edit] The Hindu cosmology and timeline is the closest to modern scientific timelines[1] and even more which might indicate that the Big Bang is not the beginning of everything,[2] but just the start of the present cycle preceded by an infinite number of universes and to be followed by another infinite number of universes.[3] The Rig Veda questions the origin of the cosmos in: "Neither being (sat) nor non-being was as yet. Large scale structure of the Universe according to one Hindu cosmology. Map 2: Intermediate neighbourhood of the Earth according to one Hindu cosmology. Map 3: Local neighbourhood of the Earth according to one Hindu cosmology. Overview of Yugas: Further elaborations from the Vedic texts[edit] Rig Veda[edit] The Puranas[edit] Multiverse in Hinduism[edit] See also[edit]

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]

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