Niels bohr

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A fascinating Reserch

Hello!!! welcome to my web page, Im Vanessa Tiberio, a student of the 4th semester of education majoring English. I want you to know that this page contains a meaningful information about an extraordinary man who has changed, in some way my vision of physics! I chose this caracther because I have always been interested in physics, but that doesn´t mean that I have studied physics or that I am good at it. but well I had the opportunity of prepare a paper about someone who had won a nobel prize in an specific subject so I thought: "well this is it", I wanted to improve my knowledge about it so here is my research about this great man who made the difference in the cientific world... you will know his biografy, work, and why did he win the nobel prize!!!

Niels Henrik David Bohr

Imagen 1

Danish physicist who was the first to apply the quantum theory, which restricts the energy of a system to certain discrete values, to the problem of atomic and molecular structure. For this work he received the Nobel Prize for Physics in 1922. He developed the so-called Bohr theory of the atom and liquid model of the atomic nucleus.

One of the foremost scientists of the 20th century, Niels Henrik David Bohr was the first to apply the quantum theory, which restricts the energy of a system to certain discrete values, to the problem of atomic and molecular structure. He was a guiding spirit and major contributor to the development of quantum mechanics and atomic physics.

Niels Henrik David Bohr was born in Copenhagen on October 7, 1885.

In the autumn of 1911 he made a stay at Cambridge, where he profited by following the experimental work going on in the Cavendish Laboratory under Sir J.J. Thomson's guidance, at the same time as he pursued own theoretical studies. In the spring of 1912 he was at work in Professor Rutherford's laboratory in Manchester, where just in those years such an intensive scientific life and activity prevailed as a consequence of that investigator's fundamental inquiries into the radioactive phenomena. Having there carried out a theoretical piece of work on the absorption of alpha rays which was published in the Philosophical Magazine, 1913, he passed on to a study of the structure of atoms on the basis of Rutherford's discovery of the atomic nucleus. By introducing conceptions borrowed from the Quantum Theory as established by Planck, which had gradually come to occupy a prominent position in the science of theoretical physics, he succeeded in working out and presenting a picture of atomic structure that, with later improvements (mainly as a result of Heisenberg's ideas in 1925), still fitly serves as an elucidation of the physical and chemical properties of the elements.

In 1913-1914 Bohr held a Lectureship in Physics at Copenhagen University and in 1914-1916 a similar appointment at the Victoria University in Manchester. In 1916 he was appointed Professor of Theoretical Physics at Copenhagen University, and since 1920 (until his death in 1962) he was at the head of the Institute for Theoretical Physics, established for him at that university. Bohr's activities in his Institute were since 1930 more and more directed to research on the constitution of the atomic nuclei, and of their transmutations and disintegrations. In 1936 he pointed out that in nuclear processes the smallness of the region in which interactions take place, as well as the strength of these interactions, justify the transition processes to be described more in a classical way than in the case of atoms (Cf.  »Neutron capture and nuclear constitution«, Nature, 137 (1936) 344).

During the Nazi occupation of Denmark in World War II, Bohr escaped to Sweden and spent the last two years of the war in England and America, where he became associated with the Atomic Energy Project. In his later years, he devoted his work to the peaceful application of atomic physics and to political problems arising from the development of atomic weapons. In particular, he advocated a development towards full openness between nations. His views are especially set forth in his Open Letter to the United Nations, June 9, 1950.

Niels Bohr died in Copenhagen on November 18, 1962.

His work

Bohr made numerous contributions to our understanding of atomic structure and quantum mechanics. He won the 1922 Nobel Prize for physics, chiefly for his work on the structure of atoms.

Bohr received his doctorate in physics from the University of Copenhagen in
1911. He then traveled to Manchester, England to study under Ernest Rutherford.

In 1913 Bohr published a theory about the structure of the atom based on an earlier theory of Rutherford's. Rutherford had shown that the atom consisted of a positively charged nucleus, with negatively charged electrons in orbit around it. Bohr expanded upon this theory by proposing that electrons travel only in certain successively larger orbits. He suggested that the outer orbits could hold more electrons than the inner ones, and that these outer orbits determine the atom's chemical properties. Bohr also described the way atoms emit radiation by suggesting that when an electron jumps from an outer orbit to an inner one, that it emits light. Later other physicists expanded his theory into quantum mechanics. This theory explains the structure and actions of complex atoms.

the negatively charged electrons revolve about the positively charged atomic nucleus because of the attractive electrostatic force according to Coulomb's law. But the electron can be taken not only as a particle, but also as a de Broglie wave (wave of matter) which interferes with itself. The orbit is only stable, if it meets the condition for a standing wave: The circumference must be an integer multiple of the wavelength. The consequence is that only special values of radius and energy are allowed. The mathematical appendix explains how to calculate these values.

Modelo de Bohr

According to classical electrodynamics, a charge, which is subject to centripetal acceleration on a circular orbit, should continuously radiate electromagnetic waves. Thus, because of the loss of energy, the electron should spiral into the nucleus very soon. By contast, an electron in Bohr's model emits no energy, as long as its energy has one of the above-mentioned values. However, an electron which is not in the lowest energy level (n = 1), can make a spontaneous change to a lower state and thereby emit the energy difference in the form of a photon (particle of light). By calculating the wavelengths of the corresponding electromagnetic waves, one will get the same results as by measuring the lines of the hydrogen spectrum.

You must not take the idea of electrons, orbiting around the atomic nucleus, for reality. Bohr's model of the hydrogen atom was only an intermediate step on the way to a precise theory of the atomic structure, which was made possible by quantum mechanics and quantum electrodynamics.

Bohr’s Involvement with the Atomic Bomb

Bohr’s understanding and ideas of fission were used to create a chain reaction process that led to the development of the atomic bomb. Bohr used his "Liquid Drop" model to help understand the fission process. During World War II, Bohr and his family fled Denmark in order to escape the Nazi threat towards the Jews. Bohr himself was half Jewish his family and escaped via fishing boat to Sweden. Bohr then traveled to England and participated in discussions regarding the atomic bomb project. Bohr traveled further yet, in 1943, to Los Alamos, New
Figura del atomo de bohr
Mexico to work with fellow Danish collegues and other scientists on the Manhattan Project. It is somewhat unclear regarding the exact amount of participation by Bohr, but it is clear that he participated in many discussion concerning the appropriate use and control of the atomic bomb or with any other form of this newly discovered energy source. Bohr was very concerned about the atomic bomb and tended to view the bomb as device that could unify nations, since it could after all, cause catastrophic damage. As part of Bohr’s efforts to promote proper use of the atomic bomb, he wrote a letter 1950 to the United Nations, discussing peaceful policies with nuclear weapons. Bohr also met with Roosevelt and Churchill regarding his attitudes about nuclear energy.

The Bohr Family

A very impressive family composed of so many intelligent people.

Parents: Christian (Professor of Physiology) and Ellen Bohr (Family of educators)
Bohr family 2

Siblings: Jenny (Older sister) and Harald (Mathematician)
His brothers

Wife: Bohr married Margrethe Norlund in 1912

Children: 4 sons: Hans Henrick (M.D.), Eric (Chemical Engineer), Aage (Ph.D, theoretical physicist), Ernest (Lawyer)

His own family

Bohr's father, Christian Bohr, professor of physiology at the University of Copenhagen, was known for his work on the physical and chemical aspects of respiration.

as the son of Christian Bohr, and his wife Ellen, née Adler. Niels, together with his younger brother Harald (the future Professor in Mathematics), grew up in an atmosphere most favourable to the development of his genius - his father was an eminent physiologist and was largely responsible for awakening his interest in physics while still at school, his mother came from a family distinguished in the field of education.

His mother, Ellen Adler Bohr, came from a wealthy Jewish family prominent in Danish banking and parliamentary circles. Bohr's scientific interests and abilities were evident early, and they were encouraged and fostered in a warm, intellectual family atmosphere. Niels's younger brother, Harald, became a brilliant mathematician.

In 1909 when his brother Harald left to pursue his own academic endeavors, Bohr hired Margrethe Norlund to type his numerous papers. One year later, the two became engaged.

Bohr was married, in 1912. Margrethe Norlund was for him an ideal companion. They had six sons, of whom they lost two; the other four have made distinguished careers in various professions. Aage Niels Bohr became a successful physicist like his father and won the Nobel Prize.

The wife and complement of Niels Bohr, Margrethe Norlund Bohr was an integral part of his life and his work. In Act I of Copenhagen, Bohr says that he is "a mathematically curious entity: not one but half of two." He paradoxically half of his marriage, and half of his friendship and collaboration with Heisenberg. Although Margrethe was not present during the conversation between Bohr and Heisenberg, her being in the play is essential since the conversation in the play is akin to Nietzsche's eternal recurrence at the personal level, an exploration of the loss of their sons: Christian, Harald, and Werner. In the play, the characters are like ghosts who haunt those who caused and participated in their pain. Like analysands trapped in memory and trauma, they talk and talk without resolution.
His wife
Her role in the play is multi-dimensional. Reed Way Dasenbrock suggests that Margrethe's presence is a way of keeping the physics at the audience's level: two physicists left to themselves would talk like physicists, but the two men have to discuss physics in terms Margrethe (and the audience of the play) can understand. Matthais Dörries similarly suggests that Margrethe is like the chorus in Greek tragedy: she clarifies the conversation/action for the audience. But she also has a more traditionally female function in that she opens the emotional discussions about Heisenberg as the enemy, and her comments keep the men from sublimating jealousy and other negative emotions into disagreements about physics. The scientific is the personal, as the political is the personal. Observer and observed are intertwined in life as in science; the resulting observations are not simple data points. As a complement to her husband, she seems at times the contrary of Heisenberg. Frayn's sharp-tongued fictionalization of her appears at odds with the usual portrait of her as a stately woman who was also a mother to his students.
After a while

In this picture you can see the lovely couple in their latest times.

In other words...

In addition to his major contributions to theoretical physics, Bohr was an excellent administrator. The institute he headed is now named for him, and he helped found CERN, Europe's great particle accelerator and research station. He died at home in 1962, following a stroke. Is buried in Copenhagen.

As you can see Bohr was an extraordinary man. He proved us that if you work hard for what you want and for what you believe, you can make your dreams come true...

"An expert is a man who has made all the mistakes which can be made, in a very narrow field." NIELS BOHR

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