La relativité restreinte expliquée en animation

Stellarium Albert Einstein - Wikipédia Albert Einstein en 1947. Il publie sa théorie de la relativité restreinte en 1905 et sa théorie de la gravitation, dite relativité générale, en 1915. Il contribue largement au développement de la mécanique quantique et de la cosmologie, et reçoit le prix Nobel de physique de 1921 pour son explication de l’effet photoélectrique[N 2]. Son travail est notamment connu du grand public pour l’équation E=mc2, qui établit une équivalence entre la masse et l’énergie d’un système. Biographie Jeunesse Son père, Hermann Einstein, né le 30 août 1847 à Buchau, est mort le 10 octobre 1902 à Milan. Les Einstein sont des juifs non pratiquants, mais un parent enseigne à Albert les éléments du judaïsme. L'intérêt d'Albert pour la science est éveillé par une boussole alors qu'il est âgé de cinq ans : l'existence d'une action à distance lui paraît « miraculeuse » et l'étonne très vivement. De douze à seize ans, il apprend en autodidacte le calcul différentiel et intégral[4]. Formation Carrière Mort Année 1905 Notes

Classificazione Annuncio Pubblicitario Chiunque abbia qualche infarinatura di Biologia sa sicuramente che la classificazione degli organismi viventi è un’attività che da lungo tempo ormai coinvolge studiosi delle Scienze Naturali provenienti da tutto il mondo e dalle epoche più disparate. Tutti nel nostro percorso scolastico abbiamo studiato che in natura c’é differenza tra un Animale, una Pianta, un Fungo o un Batterio (e non solo a livello visivo-esteriore). Ci hanno detto che essi appartengono a categorie differenti, le cosiddette categorie tassonomiche, che ci permettono di distinguere gli organismi diversi tra loro e raggruppare invece quelli simili. Fin qui credo che tutti siamo d’accordo. Tuttavia, nel tempo numerose ricerche, basate soprattutto sullo studio del DNA e dei caratteri molecolari, hanno mostrato che in alcuni casi erano necessarie delle precisazioni e/o delle vere e proprie revisioni. La nascita della sistematica Nomenclatura binomia, trinomia e categorie tassonomiche Domini Regni

Le mystère du manuscrit de Voynich [2011] Cosmic Inflation Explained Free excerpt from The PHD Movie 2! - Watch this free clip from the movie that Nature called "Astute, funny"! Watch the new movie! Summer Hiatus - PHD has been on Summer Hiatus while Jorge finishes the new PHD Movie. The PHD Movie 2 OFFICIAL TRAILER - is out!! Filming is done! Coming to Campuses this Fall! The Science Gap - Watch Jorge's TEDx Talk:

Trois lois de Clarke L'auteur de science-fiction Arthur C. Clarke a formulé les trois lois suivantes : Origine[modifier | modifier le code] Les lois de Clarke ont été proposées par Arthur C. Dans une révision de 1973 de Profiles of the Future, Clarke reconnut la deuxième loi et proposa la troisième dans le but d'en arrondir le nombre, ajoutant : « Comme les trois lois étaient suffisantes pour Newton, j'ai modestement décidé de m'arrêter là ». Parmi ces trois lois, la troisième est la plus connue et la plus citée : celle-ci codifie en effet ce qui est sans doute la plus significative de ses rares contributions formelles à la fiction spéculative. Références[modifier | modifier le code] ↑ (en) Arthur Charles Clarke, Profiles of the Future, 1973↑ Gregory Bendford, Fondation en péril, HarperPrism, 1997↑ (en) « The Deepening Paradox » [archive], sur kschroeder.com (consulté le 18 août 2014)

sciences & philosophies ascociées Time travellers: please don’t kill Hitler | Dean Burnett If you find yourself suddenly gaining access to a time machine, what’s the first thing you’d do? If you said “kill Adolf Hitler”, then congratulations; you’re a science-fiction character. Actually, the whole “access to a time machine” thing suggested that already, but the desire to kill Hitler clinches it. Any time-travelling sci-fi character (at least ones created by Western society) seems to want to kill Hitler, so much so that there’s a trope about how it’s impossible. That attempting to kill Hitler has become such a common sci-fi plot device speaks volumes. What about Stalin? It’s understandable. Ethical quandary Could you actually kill another human being? But let’s assume you are willing to kill one to save millions of others. Maybe later, when the Reich is in place but he hadn’t committed genocide yet. Wider context Problems rarely exist in isolation. Chaos theory Say whoever replaced him was ineffectual and the war ended with reduced loss of life and destruction. Cultural reference

Scientific Proof Is A Myth You've heard of our greatest scientific theories: the theory of evolution, the Big Bang theory, the theory of gravity. You've also heard of the concept of a proof, and the claims that certain pieces of evidence prove the validities of these theories. Fossils, genetic inheritance, and DNA prove the theory of evolution. The Hubble expansion of the Universe, the evolution of stars, galaxies, and heavy elements, and the existence of the cosmic microwave background prove the Big Bang theory. Except that's a complete lie. Reality is a complicated place. We also can't observe or measure everything. In order to come up with a model capable of predicting what will happen under a variety of conditions, we need to understand a few things. What we're capable of measuring, and to what precision. Our best theories, like the aforementioned theory of evolution, the Big Bang theory, and Einstein's General Relativity, cover all of these bases. This doesn't mean it's impossible to know anything at all.

phisique Are We Living in a Simulation? It turns out I’ve got a few things in common with Elon Musk, the founder of SpaceX and Tesla. We’ve both got Canadian passports, we’re absolutely fascinated by space exploration and believe that humanity’s future is in the stars. Oh, and we’re kind of obsessed at the possibility that we might be living in a computer simulation. In the recent 2016 Code Conference, Elon Musk casually mentioned his fascination with the concept first put forth by the scientist Nick Bostrom. Apparently, Musk has brought up the argument so many times, he’s banned from discussing it in hot tubs. I haven’t received any bans yet, but I’m sure that’s coming. The argument goes like this: Advanced civilizations (such as our own) will develop faster and faster computers, capable of producing better and better simulations. Computer model of the Milky Way and its smaller neighbor, the Sagittarius dwarf galaxy. Not only will the simulations get more sophisticated, but the total number of simulations will go up. Related

ICBS Everywhere › The Logic of Causal Conclusions: How we know that fire burns, fertilizer helps plants grow, and vaccines prevent disease I usually cringe when I read a comment by a skeptic arguing that “correlation does not prove causation”. Of course, it’s true that correlation does not prove causation. It’s even true that correlation does not always imply causation. There are many great examples of spurious correlations which demonstrate clearly just how silly it is to extrapolate cause from correlation. And the problem is not trivial. I cringe because I am afraid that this oversimplification leads people to think that correlation plays no role in causal inference (inferring that X causes Y). What’s more, that sound bite does nothing to educate people about how and when we should infer cause. Causation From Correlation A classic example used to illustrate the problem is the very real relationship between ice cream sales and violent crime. So, should we stop selling ice cream? There are basically two problems with drawing causal conclusions from a correlation: Causes So if correlation doesn’t prove causation, what does?