Werner Heisenberg( German physicist, Nobel Prize in Physics, 1932)
Comments for Werner Heisenberg
Biography Werner Heisenberg
December 5, 1901, Mr.. - February 1, 1976
The German physicist Werner Karl Heisenberg was born in Duisburg in the family in August Heisenberg, professor of Greek language, University of Munich, and Annie nee Vekleyn. Childhood Years G. held in Duisburg, where he studied at the gymnasium Maximilian. In 1920, Mr.. he entered the University of Munich, where he studied physics under the guidance of the famous Arnold Sommerfeld. G. was an outstanding student and already in 1923. doctorate. She was devoted to some aspects of quantum theory. The following year he spent at the University of GцTttingen as an assistant to Max Born, and then received a scholarship Rockefeller Foundation, went to Niels Bohr in Copenhagen, where he stayed until 1927, except for lengthy visits to Gottingen.
. The greatest interest in Mr.
. called unsolved problems of atomic structure and there is a discrepancy model proposed by Bohr. In 1925, during a short rest after a bout of hay fever D. in a burst of inspiration saw a completely new approach that allows to apply quantum theory to resolve all difficulties in the Bohr model. A few weeks later he presented his ideas in the article. Max Planck laid the foundations of quantum theory in 1900. He explained the relationship between body temperature and radiation emitted by them, put forward the hypothesis that the energy is emitted in small discrete chunks. The energy of each of such portions, or quanta, as suggested by the name of Albert Einstein, is proportional to the frequency of radiation. The concept of a quantum of energy was radically new, since in the last century it was shown that the radiation, such as light, distributed in the form of continuous waves.
In 1905, Mr.. Einstein used the photons to explain the mysterious properties of the photoelectric effect - emission of electrons a metal surface illuminated by ultraviolet light. More intense radiation leads to an increase in the number of electrons emitted from the surface, but not their energy. Einstein suggested that every quantum (light or other radiant energy), subsequently called a photon, transfers the energy of one electron. A certain fraction of the energy expended on the release of an electron, and the rest goes into kinetic energy, ie. manifested in the form of the electron velocity. Flow incident on the metal surface is more intense radiation contains a greater number of photons that release and a greater number of electrons, but the energy of each photon is fixed, and this placed a limit on the speed of electrons.
. Around 1913
. Bohr proposed his atomic model: around the dense central core of the orbits of different radius turn electrons. Using quantum theory, he showed that atoms excited by combustion of a substance or an electric discharge, radiates energy at some characteristic frequencies. According to Bohr, was permitted only well-defined electron orbits. When an electron 'jumps' from one orbit to another, with less energy, the excess it is converted into a quantum of radiation emitted at a frequency determined by Planck's theory, the energy difference between levels. Bohr's model, first a great success, but soon it took to introduce an amendment to eliminate the discrepancy between theory and experimental data. Many scholars have pointed out that, despite its apparent simplicity, it can not serve as a basis for a coherent approach to solving many problems in quantum physics.
. A brilliant idea that came to mind, was held to consider the quantum events as a phenomenon in a completely different level than in classical physics
. He walked up to him as to the phenomena of not allowing an accurate visual representation, for example with pictures circulating on the orbits of electrons. Instead of visual images of G. proposed an abstract, purely mathematical representation based on the use of 'in principle observable' variables, such as the frequency of spectral lines. In the derived T. equation included a table of observed variables: frequency, spatial coordinates and momenta. He pointed out the rules to allow for over the tables of various mathematical operations. Born to recognize the tables T. long known to mathematicians of the matrix and showed that the operations on them can be produced according to the rules of matrix algebra - a well-developed field of mathematics, but little known at that time physicists. Born, his student, Pascual Jordan and Mr.. developed this concept in the matrix mechanics and created a method to apply the quantum theory in studies of the structure of the atom.
. A few months Erwin Schrodinger proposed a different formulation of quantum mechanics, which describes these phenomena in the language of wave concepts
. Schrodinger approach originates in the works of Louis de Broglie, . hypothesis of the so-called matter waves: just, . the light, . traditionally considered waves, . can have particle properties (photons, . or quanta of radiation), . particles can have wave properties,
. Later it was proved that matrix and wave mechanics, in essence, equivalent. Taken together, they form what is now called quantum mechanics. Soon, quantum mechanics has been extended P.A. M. Dirac, which included elements of the wave equation of Einstein's relativity theory.
In 1927, Mr.. G. became professor of theoretical physics at Leipzig University. In the same year he published a paper containing the wording of the uncertainty principle. Its principle G. brought as a result of matrix multiplication. The multiplication of normal numbers of the order of the factors is irrelevant, and the multiplication of matrices it is very important. In calculating the multiplication of some pairs of variables, . such as momentum of the particle and its spatial coordinate, . response in the matrix mechanics would depend on, . which of the variables (momentum and spatial coordinates) is in the first place,
. The concept of ordering quantities proved to be very deep. It meant that the precise definition of the same size effect on the other, so the values of two variables simultaneously is impossible to know with absolute certainty. Physical quantities are usually known by measuring. Each measurement contains some error, but the experimenter has always hoped to reduce it by using better equipment or more sophisticated techniques. The uncertainty principle sets a limit for the accuracy of measurements. He claims that the product of measurement errors of the two quantities can not be less than some fixed number - Planck's constant. This number is literally permeates the entire quantum theory, because the quantum energy of radiation is the product of Planck's constant and frequency.
. When the measurement error of both quantities are relatively large, as in everyday life, the uncertainty principle is not very effective, but at the atomic level, it is very important
. For example, rather than be fixed electron position in space, the more uncertain is its speed. Even theoretically the electron can not be ascribed both absolutely certain spatial coordinates and exactly known velocity. G. proposed the following explanatory example: to 'see' an electron in a hypothetical sverhmikroskop, it should send a 'light' with a wavelength comparable to the size of the electron. From the quantum theory implies that the quantum of such a light should have so much energy that in a collision with an electron, he set it aside. Observation of perturbations and makes changes to what is observed. According to the Copenhagen interpretation (named in honor of Niels Bohr, . intensively into this issue in Copenhagen), . won the highest recognition in modern physics, . uncertainty principle restricts the quantum-mechanical description of the allegations about the relative probabilities of outcomes of experiments and does not predict the exact numerical values of measured physical quantities.,
. Another success of the new quantum mechanics has predicted the existence of two forms of hydrogen molecule
. Normally, each hydrogen molecule consists of two coupled atoms (nucleus of each atom consists of one proton). It is assumed that the nucleus rotates around its own axis like a top (quantum mechanics rejects such a simple picture, but remains a concept such as spin, or angular momentum, which characterizes the rotation of the nucleus around its own axis). Since the proton carries a positive electric charge, its spin has the character of electric current and generates a magnetic field that interacts with other charged particles and magnetic fields. In one form of the hydrogen molecule the spins of two nuclei of the same direction (clockwise or against it). In another nuclear spins are directed in opposite directions. Soon it was proven through the observation of line spectra. Since the relative orientation of the spins affect the position of energy levels, transitions between slightly different levels are accompanied by radiation with different frequencies. This experimental confirmation of the assumption T. reinforced his theoretical studies.
In 1933. G. was awarded the Nobel Prize in Physics 1932. 'for the creation of quantum mechanics, the use of which led inter alia to the discovery of allotropic forms of hydrogen'.
At the University of Leipzig G. remained until 1941. During his stay in Leipzig, he performed important work on ferromagnetism (type of magnetism, characteristic of strongly magnetic materials such as iron) and quantum electrodynamics (the latter - in collaboration with Wolfgang Pauli). Immediately after the discovery of the neutron by James Chadwick in 1932. G. hypothesis according to which the atomic nucleus must consist of protons and neutrons, held by the nuclear exchange interaction.
In 1941, Mr.. G. was appointed professor of physics at Berlin University and director of the Kaiser Wilhelm Institute of Physics. Although Mr.. not a supporter of the Nazi regime, he nonetheless led the Germanic project on atomic research. American physicists, who knew the ability of GM, feared that he might create for Germany a bomb they were working in the U.S.. G. hoped to obtain nuclear energy, . but the incompetence of the government, . his folly, . expulsion of Jewish scientists and alienation from many other established so serious obstacles to research, . that participants germanskogo nuclear project could not even build a nuclear reactor,
. After the war, Mr.. Among other German physicists, was captured and interned in the UK. In Germany, he returned in 1946. and was appointed professor of physics at GцTttingen and director of the Max Planck Institute (formerly the Kaiser Wilhelm Physical Institute). Fulfilling these high duties, Mr.. participated in the program for generating nuclear power. He spoke with public criticism of Chancellor Konrad Adenauer for inadequate funding of nuclear technology by the Government. G. was among those scientists who warned the world about the danger of nuclear war. He belonged to the opponents of nuclear armament of the Bundeswehr. G. performed a number of studies on the theory of hydrodynamic turbulence, superconductivity and the theory of elementary particles.
In 1937, Mr.. G. married Elisabeth Schumacher. They had four daughters and three sons. Thin pianist G. often played in chamber ensembles with members of his family. G. he died February 1, 1976 g. Munich.
G. was awarded the gold medal Barnard 'For his outstanding scientific achievements,' Columbia University (1929), . Matteuchchi gold medal of the National Academy of Sciences of Italy (1929), . Medal of the Max Planck Germanskogo Physical Society (1933), . bronze medal of the National Academy of Sciences USA (1964), . international gold medal of Niels Bohr Danish Society of Civil Engineers, . electricians and mechanics (1970),
. He was awarded honorary degrees from universities in Brussels, . Budapest, . Copenhagen, . Zagreb and the Technical University of Karlsruhe, . was a member of Academies of Sciences of Norway, . GцTttingen, . Spain, . Germany and Romania, . and the Royal Society of London,
. American Philosophical Society, the New York Academy of Sciences. Royal Irish Academy and the Japanese Academy.