La relativité - 1,2,3,4, dimensions La théorie de la Relativité Concepts fondamentaux Corpus théorique (I) Avant de poursuivre cette initiation à la relativité, il est indispensable d'introduire quelques rudiments de mathématiques afin de fourbir votre esprit avec la meilleure arme intellectuelle qui soit pour comprendre la suite du récit. Il faut en effet à présent définir quelques notions fondamentales, quitte à devoir faire usage d’un peu de symbolique mathématique. J’ai tout imaginé pour vous éviter cette partie “dure” du sujet , en tous cas sa partie nettement moins littéraire, c’est-à-dire les définitions du cadre relativiste; mais à mesure que je relisais ce passage tout en le rédigeant, je me suis finalement rendu compte que s’il y avait une chose sur laquelle il fallait bien insister quand on apprend une nouvelle matière, c’était par définition les notions de bases. 1,2, 3, 4 dimensions Nous savons que l’Univers est une construction multidimensionnelle. A lire : Flatland, E.Abbott, 1884 (PDF) Vecteur, champ et tenseur
Exploring Earth’s History with Wolfram|Alpha—Wolfram|Alpha Blog We humans often notice the passage of time by observing our watches; the movement of the Sun, Moon, and stars across the sky; or by the records left by our ancestors in diaries or other historical records—but these are just fleeting moments in the eyes of geological time. We are used to thinking about recorded history. But recorded history is just a blink when compared to the length of time called pre-history. Recorded history only goes back a few thousand years. It’s hard for humans to grasp just how long the Earth has been here. We often take our surroundings for granted. By studying the oldest rocks on Earth and even those found on the Moon during the Apollo Moon missions, scientists have found that the Earth has been around for about 4.5 billion years. The Proterozoic Eon lasted 1.9 billion years (another 41% of Earth’s history), and the events include the deposition of banded iron formations in the rocks.
Data Circle Animation - Music Interfaces - Awwwards This website uses cookies to ensure you get the best experience on our website. Learn More.GOT IT! Collections / Data Circle Animation 5 Collect me Data Circle Animation Added by Awwwards Team to Music Interfaces Similar resources Nothingness: Why nothing matters Our pursuit of naught provides profound insights into the nature of reality Read more: "The nature of nothingness" SHAKESPEARE had it right, even in ways he couldn't have imagined. For centuries, scientists have indeed been making much ado about nothing - and with good reason. Nothing, or rather what we've long taken to be nothing, may be the key to understanding everything from why particles have mass to the expansion of the universe. As explored in this special issue of New Scientist (see "The nature of nothingness"), nothing is a rich and subtle subject whose biography is far from finished. The modern story of nothing began with a thought experiment dreamed up by Isaac Newton. With that answer, Newton made something out of nothing. The discovery of quantum mechanics took the story of nothing further still. This year's Nobel prize in physics recognises the power of nothing on cosmic scales. Profile New Scientist Not just a website! More From New Scientist More from the web (YouTube)
permebility Map your moves Data This map distills more than 4000 moves from over 1700 people, collected in an informal survey by WNYC, a New York based public radio station. For generating the geo–coordinates from the entered ZIP codes, I used the free bulk geocoder at gpsvisualizer.com. Mapping As most moves occurred from, to or within the New York area, this area displayed enlarged in the white circle at the center of the graphic. Visual markers Each circle corresponds to one zip code area. Actually, it is consists of two overlaid circles: a red one for people moving out of the area, and a blue one for people moving to the area. Interaction Click one of the circles to inspect only moves to or from this area. Details On the right, you can find some statistics on why and when people moved to the selected areas. You can directly compare the lengths of the red (for people moving away from the selected areas) and blue (for people moving to the selected areas) bars to spot trends and peculiarities.
The Worlds of David Darling "Nothing" doesn't exist. Instead, there's "quantum foam" What is nothing? This is a question that has bothered philosophers as far back as the ancient Greeks, where they debated the nature of the void. They had long discussions trying to determine whether nothing is something. While the philosophical facets of this question pose some interest, the question is also one that the scientific community has addressed. (Big Think’s Dr. It’s nothing, really What would happen if scientists took a container and removed all the air out of it, creating an ideal vacuum that was entirely devoid of matter? However, what if scientists also cooled the container to the lowest possible temperature (absolute zero), so it radiated no energy at all? That’s where things become counterintuitive. The nature of “nothing” The laws of quantum mechanics are confusing, predicting that particles are also waves and that cats are simultaneously alive and dead. These quantum principles have mind-bending consequences for anyone trying to understand the nature of nothing.
Digital Podge 2009 - Measurable Fun | 17th December 2009 Digital Podge 2009 17th December 2009 Swedish Podge 2010 Hubble's Panoramic View Several million stars are vying for attention in this NASA/ESA Hubble Space Telescope image of a raucous stellar breeding ground in 30 Doradus, located in the heart of the Tarantula nebula. 30 Doradus is the brightest star-forming region in our galactic neighbourhood and home to the most massive stars ever seen. The nebula resides 170 000 light-years away in the Large Magellanic Cloud, a small, satellite galaxy of our Milky Way. No known star-forming region in our galaxy is as large or as prolific as 30 Doradus. The image comprises one of the largest mosaics ever assembled from Hubble photos and consists of observations taken by Hubble’s Wide Field Camera 3 and Advanced Camera for Surveys, combined with observations from the European Southern Observatory’s MPG/ESO 2.2-metre telescope that trace the location of glowing hydrogen and oxygen. The image is being released to celebrate Hubble’s 22nd anniversary. The colours come from the glowing hot gas that dominates regions of the image. Notes
10 Strange Things About The Universe Space The universe can be a very strange place. While groundbreaking ideas such as quantum theory, relativity and even the Earth going around the Sun might be commonly accepted now, science still continues to show that the universe contains things you might find it difficult to believe, and even more difficult to get your head around. Theoretically, the lowest temperature that can be achieved is absolute zero, exactly ? One of the properties of a negative-energy vacuum is that light actually travels faster in it than it does in a normal vacuum, something that may one day allow people to travel faster than the speed of light in a kind of negative-energy vacuum bubble. One prediction of Einstein’s theory of general relativity is that when a large object moves, it drags the space-time around it, causing nearby objects to be pulled along as well. Relativity of Simultaneity Since this extra dimension is so small, only tiny objects, such as particles, can move along it. Antimatter Retrocausality
Space.com Buy This Infographic as a Full-Size Poster Astronomers have discovered more than 700 alien planets beyond the solar system, and the count is rising all the time. Some are large and hot, and others are smaller and cooler, but scientists are still on the lookout for an Earth twin. They just got closer, with the announcement Dec. 5 of a planet found by NASA's Kepler space telescope to lie in the habitable zone around its star where liquid water, and perhaps life, could exist. You can purchase a 20"x60" poster of this SPACE.com infographic on high-quality 14G Photo Paper from the SPACE.com store here: Buy Poster Embed: Paste the code below into your site. <a href=" alt="Astronomers searching for another Earth are getting closer, thanks to recent discoveries by the Kepler space telescope. " src="
Your Sky by John Walker Welcome to Your Sky, the interactive planetarium of the Web. You can produce maps in the forms described below for any time and date, viewpoint, and observing location. If you enter the orbital elements of an asteroid or comet, Your Sky will compute its current position and plot it on the map. Your Sky provides three ways to view the sky with links, where appropriate, among the various presentations. Sky Map The sky map shows the entire sky as viewed from a given location at a specified time and date. To make a sky map, enter the latitude and longitude of your observing site in the boxes below (be sure to check the correct “North/South” and “East/West” settings) and press the “Make Sky Map” button below the form. Horizon Views Horizon Views, showing the stars above the horizon as seen from a specified observing site at a given date and time. The Virtual Telescope Your Sky's Virtual Telescope is your Humble Soft Telescope of the Web. Your Sky help Related Software On the Web:
Voyager - The Interstellar Mission Pioneers 10 and 11, which preceded Voyager, both carried small metal plaques identifying their time and place of origin for the benefit of any other spacefarers that might find them in the distant future. With this example before them, NASA placed a more ambitious message aboard Voyager 1 and 2-a kind of time capsule, intended to communicate a story of our world to extraterrestrials. The Voyager message is carried by a phonograph record-a 12-inch gold-plated copper disk containing sounds and images selected to portray the diversity of life and culture on Earth. The contents of the record were selected for NASA by a committee chaired by Carl Sagan of Cornell University, et. al. Dr. Sagan and his associates assembled 115 images and a variety of natural sounds, such as those made by surf, wind and thunder, birds, whales, and other animals.