Charles Darwin Charles Robert Darwin, FRS (/ˈdɑrwɪn/;[1] 12 February 1809 – 19 April 1882) was an English naturalist and geologist,[2] best known for his contributions to evolutionary theory.[I] He established that all species of life have descended over time from common ancestors,[3] and in a joint publication with Alfred Russel Wallace introduced his scientific theory that this branching pattern of evolution resulted from a process that he called natural selection, in which the struggle for existence has a similar effect to the artificial selection involved in selective breeding.[4] Darwin published his theory of evolution with compelling evidence in his 1859 book On the Origin of Species, overcoming scientific rejection of earlier concepts of transmutation of species.[5][6] By the 1870s the scientific community and much of the general public had accepted evolution as a fact. Biography Early life and education Painting of seven-year-old Charles Darwin in 1816. Voyage of the Beagle Death and funeral Works
Einstein Pics Rare \ Einstein's father Einstein's mother House of Einstein Einstein's childhood photo School class photograph in Munich, 1889. Einstein is in the front row, second from right. Einstein in the Bern patent office Leonardo da Vinci Leonardo is revered for his technological ingenuity. He conceptualised flying machines, an armoured vehicle, concentrated solar power, an adding machine,[7] and the double hull, also outlining a rudimentary theory of plate tectonics. Relatively few of his designs were constructed or were even feasible during his lifetime,[nb 2] but some of his smaller inventions, such as an automated bobbin winder and a machine for testing the tensile strength of wire, entered the world of manufacturing unheralded.[nb 3] He made substantial discoveries in anatomy, civil engineering, optics, and hydrodynamics, but he did not publish his findings and they had no direct influence on later science.[8] Life Childhood, 1452–1466 Leonardo's earliest known drawing, the Arno Valley (1473), Uffizi Verrocchio's workshop, 1466–1476 Professional life, 1476–1513 In 1482 Leonardo, who according to Vasari was a most talented musician,[25] created a silver lyre in the shape of a horse's head. Old age, 1513–1519 Personal life
En 1911 déjà, Albert Einstein conseillait d'ignorer les trolls ! Les grands esprits souvent s'estiment, plus souvent encore s'entraident. Ceci était particulièrement vrai avec Albert Einstein. Et à l'heure où nos forums sont remplis de trolls et d'autres "haters", le père de la relativité restreinte prodiguait en 1911 déjà, un sage conseil : ignorer les éternels aigris ! Nous sommes donc en 1911. De retour chez elle, elle dut faire face à une foule en colère, la forçant elle et ses filles à rester chez des amis… Une situation quelque peu familière ces derniers temps, non ? Voici donc la lettre de Albert Einstein à Marie Curie. […] Je dois vous dire à quel point j’admire votre intelligence, votre volonté et votre honnêteté, et je me considère heureux d’avoir fait votre rencontre en personne à Bruxelles. Les plus perspicaces auront remarqué le post-scriptum très scientifique juste après ces mots réconfortants… Une belle histoire à apporter au crédit de ce grand bonhomme qu’était Albert Einstein.
James Clerk Maxwell James Clerk Maxwell FRS FRSE (13 June 1831 – 5 November 1879) was a Scottish[2][3] mathematical physicist.[4] His most notable achievement was to formulate the classical theory of electromagnetic radiation, bringing together for the first time electricity, magnetism, and light as manifestations of the same phenomenon. Maxwell's equations for electromagnetism have been called the "second great unification in physics"[5] after the first one realised by Isaac Newton. With the publication of A Dynamical Theory of the Electromagnetic Field in 1865, Maxwell demonstrated that electric and magnetic fields travel through space as waves moving at the speed of light. Maxwell proposed that light is an undulation in the same medium that is the cause of electric and magnetic phenomena.[6] The unification of light and electrical phenomena led to the prediction of the existence of radio waves. Life[edit] Early life, 1831–39[edit] Education, 1839–47[edit] Edinburgh Academy, where Maxwell was schooled ...
Einstein - sa vie - biographie Effet photoélectrique: la lumière peut-être considérée comme constituée de particules, les photons. Leur énergie est proportionnelle à la fréquence du rayonnement: E = hn L'énergie contenue dans un faisceau de lumière est transférée sous forme de paquets, les quanta. Personne n'admet cette théorie. Elle sera redécouverte expérimentalement 10 ans plus tard par Robert Andrews Millikan. Puis, Einstein contribue au développement qui fusionne les modèles ondulatoires et corpusculaires de la lumière. Einstein émet l'idée que les mesures d'espace et de temps dépendent de l'évaluation de la simultanéité de deux événements distants. Il développe une théorie basée sur deux postulats : le principe de la relativité, selon lequel toutes les lois de la physique sont identiques dans tous les repères inertiels, et le principe de l'invariance de la vitesse de la lumière, selon lequel la vitesse de la lumière dans le vide est une constante universelle. Quasiment personne ne comprit l'argumentation d'Einstein.
Isaac Newton Sir Isaac Newton PRS MP (/ˈnjuːtən/;[8] 25 December 1642 – 20 March 1726/7[1]) was an English physicist and mathematician (described in his own day as a "natural philosopher") who is widely recognised as one of the most influential scientists of all time and as a key figure in the scientific revolution. His book Philosophiæ Naturalis Principia Mathematica ("Mathematical Principles of Natural Philosophy"), first published in 1687, laid the foundations for classical mechanics. Newton made seminal contributions to optics, and he shares credit with Gottfried Leibniz for the development of calculus. Newton built the first practical reflecting telescope and developed a theory of colour based on the observation that a prism decomposes white light into the many colours of the visible spectrum. He formulated an empirical law of cooling, studied the speed of sound, and introduced the notion of a Newtonian fluid. Life Early life Isaac Newton (Bolton, Sarah K. Middle years Mathematics Optics
Gravitation Edgar Poe (1809 – 1849) – Eurêka Il y décrit le vertige qui s'empare de nous lorsque nous essayons de concevoir les conséquences de la loi de la gravitation universelle. Extrait: «Que le lecteur s'arrête ici un moment avec moi pour contempler la miraculeuse, ineffable et absolument inimaginable complexité de rapports impliquée dans ce fait, que chaque atome attire chaque autre atome... Mais quelle est cette vérité que nous sommes actuellement appelés à comprendre? Si je me propose de mesurer l'influence d'un seul atome sur un atome voisin dans un rayon solaire, je ne puis pas accomplir mon dessein sans d'abord compter et peser tous les atomes de l'Univers et définir la position précise de chacun à un moment particulier de la durée. Si je m'avise de déplacer, ne fut-ce que de la trillionième partie d'un pouce, le grain microscopique de poussière posé maintenant sur le bout de mon doigt, quel est le caractère de l'action que j'ai eu la hardiesse de commettre ? Traduction de Charles Baudelaire
Alhazen In medieval Europe, he was honored as Ptolemaeus Secundus ("Ptolemy the Second")[10] or simply called "The Physicist".[11] He is also sometimes called al-Basri (Arabic: البصري) after Basra, his birthplace.[12] He spent most of his life close to the court of the Caliphate in Cairo and earned his living authoring various treatises and tutoring members of the nobilities.[13] Overview[edit] Biography[edit] Born c. 965 in Basra, which was then part of the Buyid emirate,[1] to an Arab family.[14][15] Legacy[edit] Front page of the Opticae Thesaurus, which included the first printed Latin translation of Alhazen's Book of Optics. Alhazen made significant contributions to optics, number theory, geometry, astronomy and natural philosophy. One of the major scientific anniversaries that will be celebrated during the 2015 International Year of Light is: the works on optics by Ibn Al-Haytham (1015). Book of Optics[edit] Main article: Book of Optics Theory of vision[edit] Alhazen on Iraqi 10 dinars G. A.
Albert Einstein 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
Galileo Galilei Galileo Galilei (Italian pronunciation: [ɡaliˈlɛːo ɡaliˈlɛi]; 15 February 1564[3] – 8 January 1642), often known mononymously as Galileo, was an Italian physicist, mathematician, engineer, astronomer, and philosopher who played a major role in the scientific revolution during the Renaissance. His achievements include improvements to the telescope and consequent astronomical observations and support for Copernicanism. Galileo has been called the "father of modern observational astronomy",[4] the "father of modern physics",[5][6] the "father of science",[6][7] and "the father of modern science".[8] Early life Galileo was born in Pisa (then part of the Duchy of Florence), Italy, in 1564,[15] the first of six children of Vincenzo Galilei, a famous lutenist, composer, and music theorist, and Giulia Ammannati. Although a genuinely pious Roman Catholic,[17] Galileo fathered three children out of wedlock with Marina Gamba. Career as a scientist Galileo, Kepler and theories of tides
La citation la plus célèbre d'Einstein est totalement incomprise - Big Think Sign up for the Starts With a Bang newsletter Travel the universe with Dr. Ethan Siegel as he answers the biggest questions of all. Which do you think is more important for your own life: imagination or knowledge? What about for the life of a scientist, like a theoretical physicist? If you’ve ever seen a poster of Einstein with a quote on it, there’s a very good chance that the quote simply says, “Imagination is more important than knowledge.” When you hear it, you might picture weighing “what you know” on one side of your mental scale, and weighing “what you can imagine” on the other side. As it turns out, though, that’s not at all what Einstein was talking about, nor what the statement “Imagination is more important than knowledge” actually referred to. While all of the planets in the Solar System orbit the Sun in the same direction, Venus, uniquely, rotates in the opposite direction. The scientific contributions of Einstein The full famous quote, in context
Edward Witten Edward Witten (/ˈwɪtən/; born August 26, 1951) is an American theoretical physicist and professor of mathematical physics at the Institute for Advanced Study in Princeton, New Jersey. Witten is a researcher in string theory, quantum gravity, supersymmetric quantum field theories, and other areas of mathematical physics. Birth and education[edit] Witten was born in Baltimore, Maryland. Witten attended the Park School of Baltimore (class of '68), and received his Bachelor of Arts with a major in history and minor in linguistics from Brandeis University in 1971. Witten attended the University of Wisconsin–Madison for one semester as an economics graduate student before dropping out.[4] He returned to academia, enrolling in applied mathematics at Princeton University in 1973, then shifting departments and receiving a Ph.D. in physics in 1976 under David Gross,[4] the 2004 Nobel laureate in Physics. Research[edit] Fields medal work[edit] M-theory[edit] Other work[edit] Awards and honors[edit]
Albert Einstein Albert Einstein (14 March 1879 – 18 April 1955) was a Jewish German theoretical physicist, widely acknowledged to be one of the greatest physicists of all time. Einstein is known for developing the theory of relativity, but he also made important contributions to the development of the theory of quantum mechanics. Together, relativity and quantum mechanics are the two pillars of modern physics. See also: Albert Einstein and politics Annus Mirabilis papers EPR paradox The Meaning of Relativity On the Method of Theoretical Physics Bohr–Einstein debates Un homme heureux est trop content du présent pour trop se soucier de l'avenir.A happy man is too satisfied with the present to dwell too much on the future.From "Mes Projets d'Avenir", a French essay written at age 18 for a school exam (18 September 1896). Autoritätsdusel ist der größte Feind der Wahrheit.Blind obedience to authority is the greatest enemy of truth. Another translation: Authority gone to one's head is the greatest enemy of truth.