Albert Einstein ( 1879-1955 )

In the 1870's, Germany realizes its unification under the aegis of the Prussia. Of a simple region where confronted the interests of the European countries, Germany is crossed(spent) to a powerful and strongly industrialized State. It is on March 14, 1879, in the climate of glorification of the force and the German culture, that is born Albert Einstein. Son(thread) of a little practising Jewish family, Albert Einstein is a solitary child. These professors see in him a slow pupil and averagely bright. This opinion comes from the fact that it(he) carries(wears) no hasty judgment and that it(he) matures for a long time every reflection. At the beginning of year 1895, Einstein is 16 years old. Demoralized by the military discipline which reigns within Gymnasium (secondary schools) and in front of the hostility of some of his(her) professors, it leaves to join his relatives(parents) installed(settled) in Italy a little while earlier after an adversity. The decision is consolidated by its refusal to be in the armed forces. It(he) decides then to prepare the competition of the Ecole polytechnique of Zurich. It(he) obtains him(it) in the second attempt, in 1896. Einstein meets there Mileva Maric, student in mathematics and in physical appearance(physics). He will marry him(it) only in 1902, after Hermann Einstein's death which opposed wildly to this marriage.

In spite of its diploma obtained in 1900 and a first publication on the capillarity in 1901, its independent spirit and its rebellious character forbid him(her) a post of assistant to the university. It is only in June, 1902, after the period of unemployment, that it(he) obtains expert's post with the Patent office of Bern. This work offers him(her) a real freedom because he can think about the problems of physical appearance(physics) the evening after his(its,her) workday.

At this beginning of XX-th century, the physics crosses a grave crisis. Both theories which allow to explain the physical phenomena seem incompatible. The mechanics, the science of the movement, rests(bases) indeed on the principle of relativity, expressed by Galilee. Nothing is absolutely immovable; everything depends on the repository in which one takes place. Now, the theory of the electromagnetism elaborated by Maxwell in the 1850's, turned out by the experimental results, describes the light as the wave propagating in the ether. But no physical description of the ether was able to be found. Only certainty, it(he) is of an absolute immobility. What shows itself in total contradiction with the principle of relativity. Another contradiction throws(casts) the physicists in the confusion. The material(subject) is established(constituted) by atoms. She(it) is so intermittent. Now, when one warms a strand, this one emits(utters) of the light; light which is inevitably continuous according to Maxwell. How some thing(matter) of intermittent can he produce a phenomenon continues? None of the physicists of time can bring of answer and the physics is in an impasse.

It is then that Einstein makes publish two goods(articles) in Annalen der Physik who show themselves revolutionary. The first one appears in March, 1905. It(he) describes how the energy of a warmed body can be transformed into brilliant energy. This transformation is possible only by considering the light established(constituted) by "grains("beads") which Einstein calls " quanta of light " (photons). The light is neither continuous then nor intermittent, but both at the same moment. Einstein does not always know in which circumstances the light shows itself continuous or intermittent but its hypothesis does not there remain less exact. The second article appears two months later, in June. He suggests resolving the problem put by the ether, in total contradiction with the principle of relativity. For Einstein, the ether does not take place to be. The only datum which allows to describe the light is its speed c, constant which that is the speed of the observer. It(he) expresses then its(his) theory of relativity which unifies the theories of the material(subject) and the light. The material(subject) as the light undergo the principle of relativity and the simultaneity of two events becomes dependent on the observer. The time is not any more an invariant concept and is too relative.

In September, 1905, Einstein adds a postscript to his(her) article and demonstrates famous formula E=mc ², leading(inferring) an equivalence between the material(subject) and the energy. Formula which will be at the origin of the development of the use of the nuclear energy for civil or military purposes. But Einstein does not stop(arrest) there. From 1907, it(he) begins to think about its(his) general theory of relativity which would allow to explain the phenomenon of the gravity. But she(it) requires bigger knowledge in modern mathematics. It(he) leaves then the Patent office and obtains an university post at first in Bern then in Prague in 1911. In 1912, he becomes a professor to the Ecole polytechnique of Zurich and finds there a former(ancient) companion, Marcel Grossmann. It(he) has finally the help(assistant) which he wished in mathematics and begins the settling of his theory. An error leads(drives) him(it) to an impasse and it(he) loses three years. But the shot is quickly corrected and the theory of relativity is finished at the end of the year on 1915. She(it) offers a new interpretation of the gravity.

The force of Newton's attraction is replaced by a deformation of the space around bodies. As a ball deforms a tense cloth(canvas) by forming there a hollow, a body modifies the space around him. It explains why all the bodies, whatever is their mass, fall with the same acceleration; they follow in fact the line of bigger hillside of the hollow formed in the space. Furthermore, Einstein expresses the fact that the space and the time can not exist without material(subject). How to verify simply this theory? If a body deforms the space around him, then the beams(shelves) of a star situated behind the sun will be diverted and the image will not be there where it should be. The observations made during an eclipse by sir Arthur Eddington, British astronomer, confirm completely Einstein's calculations. The general theory of relativity is turned out. The media seize then the history and offer to Einstein the gratitude(recognition) and the glory. The science becomes with the eyes of the world a symbol of peace and reconciliation: an Englishman confirmed the theory of a German! An illusion which will be soon swept(annihilated) by the events.

But Einstein's new popularity allows him(her) to resume its political activities and the help(assistant) to promote its peace ideal. It(he) defends(forbids) the cause of the Jewish people and militates in favour of the construction of a high-level university in Palestine. A tour in the United States in 1921 offers him(her) the necessary capital.

Jewish, pacifist and internationalist, Einstein undergoes quickly the lightnings of the extremists National Socialists. It(he) comes back from a journey in the United States when Hitler takes the power in 1933. It(he) does not return in Berlin and joins the scholars of the Institute for Advanced Study de Princeton. It(he) will take the American nationality in 1940. The exile does not prevent him(it) from pursuing its political activities. It(he) saves numerous European researchers and convinces the president Roosevelt to develop the program of the nuclear bomb(spray) before Germany reaches there. He will regret bitterly his gesture and will support, of 1945 in his death, in 1955 , the action of the emergency Committee of the scholars atomistes which aims to limit the interventions of the State in the scientific research.

If Einstein is respected and listened, there are not less(fewer) of it, at the end of the life, prop up it with the physicists' young generation as Heisenberg, Pauli and especially Bohr. Indeed, Einstein put the foundations of a new theory, the quantum theory, which he does not accept. This theory forbids any real representation of the physical elementary objects as electrons, protons, etc. They can be described only in terms of probability: probability that they follow a certain trajectory, that they have a certain position, a certain speed. Now Einstein does not adhere to this probabiliste vision of the reality. For him, " God does not dice ". It(he) refuses that the result of an experience(experiment) can not be unique(only) and predicted with certainty. For him, the quantum mechanics are at least otherwise inaccurate, incomplete. Einstein shows himself in it the last one of the classic physicists.

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