Cyclic model

A cyclic model (or oscillating model) is any of several cosmological models in which the universe follows infinite, or indefinite, self-sustaining cycles. For example, the oscillating universe theory briefly considered by Albert Einstein in 1930 theorized a universe following an eternal series of oscillations, each beginning with a big bang and ending with a big crunch; in the interim, the universe would expand for a period of time before the gravitational attraction of matter causes it to collapse back in and undergo a bounce. Overview[edit] In the 1920s, theoretical physicists, most notably Albert Einstein, considered the possibility of a cyclic model for the universe as an (everlasting) alternative to the model of an expanding universe. However, work by Richard C. One new cyclic model is a brane cosmology model of the creation of the universe, derived from the earlier ekpyrotic model. Other cyclic models include Conformal cyclic cosmology and Loop quantum cosmology. See also[edit] Related: .caisson test • .caisson test

Curse of dimensionality The curse of dimensionality refers to various phenomena that arise when analyzing and organizing data in high-dimensional spaces (often with hundreds or thousands of dimensions) that do not occur in low-dimensional settings such as the three-dimensional physical space of everyday experience. The term curse of dimensionality was coined by Richard E. Bellman when considering problems in dynamic optimization.[1][2] The "curse of dimensionality" depends on the algorithm[edit] The "curse of dimensionality" is not a problem of high-dimensional data, but a joint problem of the data and the algorithm being applied. It arises when the algorithm does not scale well to high-dimensional data, typically due to needing an amount of time or memory that is exponential in the number of dimensions of the data. When facing the curse of dimensionality, a good solution can often be found by changing the algorithm, or by pre-processing the data into a lower-dimensional form. Combinatorics[edit] Sampling[edit] .

The quilted universe Dyson's eternal intelligence The intelligent beings would begin by storing a finite amount of energy. They then use half (or any fraction) of this energy to power their thought. When the energy gradient created by unleashing this fraction of the stored fuel was exhausted, the beings would enter a state of zero-energy-consumption until the universe cooled. Two recent observations have presented problems for Dyson's scenario. However, even if intelligence cannot continue its own survival indefinitely in an ever-expanding Universe, it may be able to create a `baby universe' via a wormhole in spacetime, add some DNA[original research?] See also[edit] References[edit]

Eternal return Eternal return (also known as "eternal recurrence") is a concept that the universe has been recurring, and will continue to recur, in a self-similar form an infinite number of times across infinite time or space. The concept is found in Indian philosophy and in ancient Egypt and was subsequently taken up by the Pythagoreans and Stoics. With the decline of antiquity and the spread of Christianity, the concept fell into disuse in the Western world, with the exception of Friedrich Nietzsche, who connected the thought to many of his other concepts, including amor fati. In addition, the philosophical concept of eternal recurrence was addressed by Arthur Schopenhauer. It is a purely physical concept, involving no supernatural reincarnation, but the return of beings in the same bodies. Premise[edit] The basic premise proceeds from the assumption that the probability of a world coming into existence exactly like our own is greater than zero (we know this because our world exists). Judaism[edit]

Créer sa réalité augmentée avec l’application Aurasma La réalité augmentée (ou RA) est la technologie qui permet d’ajouter des éléments virtuels (texte, image, vidéo, animation, son, sensation tactile…) à notre environnement proche. Aurasma, c’est tout d’abord une application mobile permettant de « lire » la réalité augmentée réalisée spécifiquement pour cette application. Elle permet également de créer sa propre réalité augmentée. En effet, on peut facilement, depuis son smartphone ou de sa tablette, incruster une image ou une vidéo sur un élément du réel. Liens de téléchargement d’Aurasma Un peu de vocabulaire : Avec l’application Aurasma, on peut créer, partager et lire des Auras. L’élément déclencheur ou Trigger image c’est ce qui est reconnu par Aurasma pour déclencher l’incrustation de l’élément virtuel ou Overlay [1]. Il est possible de créer des canaux ou channels dans lesquels seront ajoutées les Auras. Pour bien commencer : Pour créer une Aura il n’est pas utile d’autoriser l’accès de l’application au service de géolocalisation.

Level IV: Ultimate ensemble 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]

Closed timelike curve In mathematical physics, a closed timelike curve (CTC) is a world line in a Lorentzian manifold, of a material particle in spacetime that is "closed", returning to its starting point. This possibility was first raised[citation needed] by Kurt Gödel in 1949, who discovered a solution to the equations of general relativity (GR) allowing CTCs known as the Gödel metric; and since then other GR solutions containing CTCs have been found, such as the Tipler cylinder and traversable wormholes. If CTCs exist, their existence would seem to imply at least the theoretical possibility of time travel backwards in time, raising the spectre of the grandfather paradox, although the Novikov self-consistency principle seems to show that such paradoxes could be avoided. Some physicists speculate that the CTCs which appear in certain GR solutions might be ruled out by a future theory of quantum gravity which would replace GR, an idea which Stephen Hawking has labeled the chronology protection conjecture.

De la carte heuristique à l'ordonnancement des tâches A. La carte heuristique dans le cadre d’un projet 1. La cartographie mentale d’idées Nous baserons notre exemple sur l’organisation d’une course d’orientation. Projet confié à un groupe d’élèves, avec un cahier des charges qui n’est pas présenté dans cet article. Lorsque l’on débute un projet il y a un échange d’idées qui se fait sur tous les points à aborder durant le projet. Lancement de MindView Dès le lancement vous pouvez immédiatement démarrer un projet, partir d’un modèle ou utiliser un fichier existant. Depuis le menu FICHIER ces mêmes éléments sont accessibles et permettent également de choisir les différents mode de présentation de votre carte heuristique : Comme tous les logiciels de mind mapping la présentation débute par un sujet central : Il faut noter que votre choix initial de présentation est réversible à tout moment et que vous pouvez passer d’un mode de présentation à un autre suivant le type de sujet traité ou pour avoir un autre visuel. 2. Élaboration de la carte mentale.