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Wolfgang Pauli: Biography [|Wolfgang Pauli]** is the most important, and famous, particle physicist you may never have heard of. Born in Vienna on April 25, 1900, Pauli went to school in Vienna before moving on to study at the University of Munich under [|Arnold Sommerfeld]. Pauli obtained his doctorate in physics In 1921 and afterwards spent a year at the University of Gottingen as an assistant to [|Max Born]. He then spent another year at the University of Copenhagen with [|Niels Bohr] and worked as a lecturer at the University of Hamburg from 1923-1928 before eventually obtaining a position as a professor of Theoretical Physics at the Federal Institute of Technology in Zurich. Pauli served as a visiting professor at the Institute for Advanced Study at Princeton from 1935 to 1936 and was later elected to be the Chair of Theoretical physics at Princeton in 1940 before finally returning to Zurich near the end of the second world war. ** **Generally recognized as one of the leaders in theoretical physics beginning while he was still a student, Pauli worked as an equal with many of the great physicists of the early twenteith century, including Neils Bohr, [|Werner Heisenberg], [|Enrico Fermi], and [|Albert Einstein], and was awarded the [|Nobel Prize] in Physics for his own work in 1945. Pauli is perhaps best known today as the developer of the [|Pauli Exclusion Principle] which helped to crystallize existing knowledge of atomic structure at the time and led to a general recognition of the two-valued variable needed to characterize the state of an electron. Pauli died of pancreatic cancer in 1958.**



 His Work  ** Pauli is widely considered to be one of the most important physicists of his time, primarily because he developed the theoretical construct for the [|neutrino], an uncharged and massless particle that carries off energy in radioactive beta-disintegration, and because he helped lay the foundation for the development of quantum mechanics through his development of the Pauli Exclusion Principle. In essence, the Pauli Exclusion Principle states that one and only one electron can occupy a given quantum space (address) at any given point in time. This principle helped crystallize existing knowledge of atomic structure at the time of its development. In simple terms, a quantum state can be thought of as a sort of address for an electron within an atom. Each address, actually a specific locus in space and time, can, according to the Exclusion Principle, be occupied by by more than one electron at a time, but only if the electrons are not identical. Thus, while an addresses can be expressed using quantum numbers, only one electron with a given energy level and spin can occupy a given address because two __identical__ electrons cannot be at the same energy level can occupy a given address in the same atom at any one point in time. The same address in a given atom can be occupied by two electrons at any given time only if the two electrons are different in terms of spin. Thus, a given atom can have two electrons at a given energy state, which is to say that the two electrons can occupy the same address, but only as long if one electron has spin up and the other has spin down. In other words, Pauli created a fourth quantum number which only has two values: an electron that's spin up has the value 1/2, and an electron that's spin down has the value -1/2. No two electrons from the same atom can have the same set of all four quantum numbers. **

For further understanding of the Pauli exclusion principle press play. 4 media type="youtube" key="B2ys6rrEASA" height="344" width="425" **Pauli had many other smaller achievements. In 1926, he used [|Heisenberg's matrix theory of modern quantum mechanics] to derive the observed spectrum of the hydrogen atom. This really helped to secure credibility for Heisenberg's theory. Pauli later proved the spin-statistics theorem, a result of quantum mechanics. This states that particles with half-integer spin are [|fermions], and that particles with integer spin are [|bosons].

Pauli made many important contributions in his career, especially in the subject of quantum mechanics, but he rarely published any of his work, preferring lengthy correspondences with his close colleagues (like Bohr and Heisenberg). Because many of his works weren't published, the recipients of Pauli's letters stole much of his work. Pauli did not seem to care that much ot of his work went uncreditied.

Pauli's contributions to theoretical physics have provided some very specific results in the modern world. [|Neutrino detectors] are presently being used to help answer some of the most fundamental questions in cosmology, while quantum mechanics provides the theoretical foundation for modern microelectronics - the engineering discipline that produced not only the computer being used to compose this article, but all of the rest of the modern electronic gadgets that have done so much to revolutionize communications, computing and the media.**

Bibliography Pictures and videos: 1. http://www.fnal.gov/pub/inquiring/timeline/images/pauli.jpg 2. http://www.gmw06.ch/English/Bilder/Semper-Bau-Raemi-b.gif 3. http://carlbrannen.files.wordpress.com/2008/03/spinreps.png 4. http://www.youtube.com/watch?v=B2ys6rrEASA 5. http://vanha.physics.utu.fi/opiskelu/kurssit/FFYS4497/bec/A1-Boson-Fermion.gif

Hyperlinks in text (in order): http://nobelprize.org/nobel_prizes/physics/laureates/1945/pauli-bio.html http://www.britannica.com/EBchecked/topic/554119/Arnold-Johannes-Wilhelm-Sommerfeld http://nobelprize.org/nobel_prizes/physics/laureates/1954/born-bio.html http://nobelprize.org/nobel_prizes/physics/laureates/1922/bohr-bio.html http://nobelprize.org/nobel_prizes/physics/laureates/1932/heisenberg-bio.html http://nobelprize.org/nobel_prizes/physics/laureates/1938/fermi-bio.html http://nobelprize.org/nobel_prizes/physics/laureates/1921/einstein-bio.html http://nobelprize.org/nobel_prizes/physics/laureates/1945/ http://www.physlink.com/Education/askexperts/ae455.cfm http://hyperphysics.phy-astr.gsu.edu/Hbase/particles/neutrino.html http://www.physics.iitm.ac.in/~labs/dynamical/pedagogy/slbala/heisenberg.pdf [|http://www.phys.psu.edu/%7Ejain/cf.html] http://galileo.phys.virginia.edu/classes/252/symmetry/Symmetry.html http://www.newscientist.com/article/dn13190 Sources used to write this page: http://nobelprize.org/nobel_prizes/physics/laureates/1945/pauli-bio.html http://www.jewishvirtuallibrary.org/jsource/biography/pauli.html http://hyperphysics.phy-astr.gsu.edu/HBASE/Pauli.html http://www.colorado.edu/physics/2000/elements_as_atoms/electron_config.html

Book Source: Pauli, Wolfgang. __Theory of Relativity__. New York: Dover Publications Inc., 1981.

For further learning about Wolfgang Pauli and his work, check these sources out: http://www.halexandria.org/dward149.htm http://www-history.mcs.st-and.ac.uk/Biographies/Pauli.html http://www.magnet.fsu.edu/education/tutorials/pioneers/pauli.html This page was written by Navid Wheeler and Nikhaar Gupta and cannot be reproduced or handled in any other way or form without consultation with Navid or Nikhaar.