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Heinrich Leutwyler
Heinrich Leutwyler (born Oct 12, 1938) is a Swiss theoretical physicist, with interests in elementary particle physics, the theory of strong interactions, and quantum field theory."Curriculum Vitae"
accessed October 13, 2022.


Early life and education

Leutwyler went to the Gymnasium in Bern and studied physics, mathematics, and astronomy at the . After the diploma in 1960 he went to the US, including . In 1962 he received his PhD ...
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Bern
german: Berner(in)french: Bernois(e) it, bernese , neighboring_municipalities = Bremgarten bei Bern, Frauenkappelen, Ittigen, Kirchlindach, Köniz, Mühleberg, Muri bei Bern, Neuenegg, Ostermundigen, Wohlen bei Bern, Zollikofen , website = www.bern.ch Bern () or Berne; in other Swiss languages, gsw, Bärn ; frp, Bèrna ; it, Berna ; rm, Berna is the ''de facto'' capital of Switzerland, referred to as the "federal city" (in german: Bundesstadt, link=no, french: ville fédérale, link=no, it, città federale, link=no, and rm, citad federala, link=no). According to the Swiss constitution, the Swiss Confederation intentionally has no "capital", but Bern has governmental institutions such as the Federal Assembly and Federal Council. However, the Federal Supreme Court is in Lausanne, the Federal Criminal Court is in Bellinzona and the Federal Administrative Court and the Federal Patent Court are in St. Gallen, exemplifying the federal nature of the Confederation. ...
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Pasadena
Pasadena ( ) is a city in Los Angeles County, California, northeast of downtown Los Angeles. It is the most populous city and the primary cultural center of the San Gabriel Valley. Old Pasadena is the city's original commercial district. Its population was 138,699 at the 2020 census, making it the 44th largest city in California and the ninth-largest city in Los Angeles County. Pasadena was incorporated on June 19, 1886, becoming one of the first cities to be incorporated in what is now Los Angeles County, following the city of Los Angeles (April 4, 1850). Pasadena is known for hosting the annual Rose Bowl football game and Tournament of Roses Parade. It is also home to many scientific, educational, and cultural institutions, including Caltech, Pasadena City College, Kaiser Permanente Bernard J. Tyson School of Medicine, Fuller Theological Seminary, ArtCenter College of Design, the Pasadena Playhouse, the Ambassador Auditorium, the Norton Simon Museum, and the USC Pacific A ...
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21st-century American Physicists
The 1st century was the century spanning AD 1 ( I) through AD 100 ( C) according to the Julian calendar. It is often written as the or to distinguish it from the 1st century BC (or BCE) which preceded it. The 1st century is considered part of the Classical era, epoch, or historical period. The 1st century also saw the appearance of Christianity. During this period, Europe, North Africa and the Near East fell under increasing domination by the Roman Empire, which continued expanding, most notably conquering Britain under the emperor Claudius (AD 43). The reforms introduced by Augustus during his long reign stabilized the empire after the turmoil of the previous century's civil wars. Later in the century the Julio-Claudian dynasty, which had been founded by Augustus, came to an end with the suicide of Nero in AD 68. There followed the famous Year of Four Emperors, a brief period of civil war and instability, which was finally brought to an end by Vespasian, ninth Roman emperor, ...
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Living People
Related categories * :Year of birth missing (living people) / :Year of birth unknown * :Date of birth missing (living people) / :Date of birth unknown * :Place of birth missing (living people) / :Place of birth unknown * :Year of death missing / :Year of death unknown * :Date of death missing / :Date of death unknown * :Place of death missing / :Place of death unknown * :Missing middle or first names See also * :Dead people * :Template:L, which generates this category or death years, and birth year and sort keys. : {{DEFAULTSORT:Living people 21st-century people People by status ...
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1938 Births
Events January * January 1 ** The Constitution of Estonia#Third Constitution (de facto 1938–1940, de jure 1938–1992), new constitution of Estonia enters into force, which many consider to be the ending of the Era of Silence and the authoritarian regime. ** state-owned enterprise, State-owned railway networks are created by merger, in France (SNCF) and the Netherlands (Nederlandse Spoorwegen – NS). * January 20 – King Farouk of Egypt marries Safinaz Zulficar, who becomes Farida of Egypt, Queen Farida, in Cairo. * January 27 – The Honeymoon Bridge (Niagara Falls), Honeymoon Bridge at Niagara Falls, New York, collapses as a result of an ice jam. February * February 4 ** Adolf Hitler abolishes the War Ministry and creates the Oberkommando der Wehrmacht (High Command of the Armed Forces), giving him direct control of the German military. In addition, he dismisses political and military leaders considered unsympathetic to his philosophy or policies. Gene ...
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University Of Mainz
The Johannes Gutenberg University Mainz (german: Johannes Gutenberg-Universität Mainz) is a public research university in Mainz, Rhineland Palatinate, Germany, named after the printer Johannes Gutenberg since 1946. With approximately 32,000 students (2018) in about 100 schools and clinics, it is among the largest universities in Germany. Starting on 1 January 2005 the university was reorganized into 11 faculties of study. The university is a member of the German U15, a coalition of fifteen major research-intensive and leading medical universities in Germany. The Johannes Gutenberg University is considered one of the most prestigious universities in Germany. The university is part of the IT-Cluster Rhine-Main-Neckar. The Johannes Gutenberg University Mainz, the Goethe University Frankfurt and the Technische Universität Darmstadt together form the Rhine-Main-Universities (RMU). History The first University of Mainz goes back to the Archbishop of Mainz, Prince-elector and ...
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Honorary Doctorate
An honorary degree is an academic degree for which a university (or other degree-awarding institution) has waived all of the usual requirements. It is also known by the Latin phrases ''honoris causa'' ("for the sake of the honour") or ''ad honorem '' ("to the honour"). The degree is typically a doctorate or, less commonly, a master's degree, and may be awarded to someone who has no prior connection with the academic institution or no previous postsecondary education. An example of identifying a recipient of this award is as follows: Doctorate in Business Administration (''Hon. Causa''). The degree is often conferred as a way of honouring a distinguished visitor's contributions to a specific field or to society in general. It is sometimes recommended that such degrees be listed in one's curriculum vitae (CV) as an award, and not in the education section. With regard to the use of this honorific, the policies of institutions of higher education generally ask that recipients ...
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Current Quark
Current quarks (also called naked quarks or bare quarks) are a description of valence quarks as the cores of the quark particles that are the invariable parts of a hadron, with their non-virtual ("real" or permanent) quarks with their surrounding "covering" of evanescent gluons and virtual quarks imagined stripped away. In quantum chromodynamics, the mass of the ''current quarks'' is called the ''current quark mass'', as opposed to the much larger mass of the composite particle which is carried in the gluon and virtual quark covering. The heavier quarks are large enough for their substantial masses to predominate over the combined mass of their virtual-particle "dressing" or covering, but the lighter quarks masses are overwhelmed by their evanescent covering's mass-energy; the light quarks' core masses are such a small fraction of the covering that the actual mass values are difficult to infer with any accuracy (hence, the data listed below for the light quarks are fraught with cav ...
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Effective Field Theory
In physics, an effective field theory is a type of approximation, or effective theory, for an underlying physical theory, such as a quantum field theory or a statistical mechanics model. An effective field theory includes the appropriate degrees of freedom to describe physical phenomena occurring at a chosen length scale or energy scale, while ignoring substructure and degrees of freedom at shorter distances (or, equivalently, at higher energies). Intuitively, one averages over the behavior of the underlying theory at shorter length scales to derive what is hoped to be a simplified model at longer length scales. Effective field theories typically work best when there is a large separation between length scale of interest and the length scale of the underlying dynamics. Effective field theories have found use in particle physics, statistical mechanics, condensed matter physics, general relativity, and hydrodynamics. They simplify calculations, and allow treatment of dissipation and ...
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Chiral Perturbation Theory
Chiral perturbation theory (ChPT) is an effective field theory constructed with a Lagrangian consistent with the (approximate) chiral symmetry of quantum chromodynamics (QCD), as well as the other symmetries of parity and charge conjugation.Heinrich Leutwyler (2012), Chiral perturbation theory
Scholarpedia, 7(10):8708.
ChPT is a theory which allows one to study the low-energy dynamics of QCD on the basis of this underlying chiral symmetry.


Goals

In the theory of the strong interaction of the standard model, we describe the interactions between quarks and gluons. Due to the running of the strong coupling constant, we can apply perturbation theory in the coupling constant only at high energies. But in the low-energy regime of QCD, the degrees of freedom are no l ...
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Quantum Chromodynamics
In theoretical physics, quantum chromodynamics (QCD) is the theory of the strong interaction between quarks mediated by gluons. Quarks are fundamental particles that make up composite hadrons such as the proton, neutron and pion. QCD is a type of quantum field theory called a non-abelian gauge theory, with symmetry group SU(3). The QCD analog of electric charge is a property called ''color''. Gluons are the force carriers of the theory, just as photons are for the electromagnetic force in quantum electrodynamics. The theory is an important part of the Standard Model of particle physics. A large body of experimental evidence for QCD has been gathered over the years. QCD exhibits three salient properties: * Color confinement. Due to the force between two color charges remaining constant as they are separated, the energy grows until a quark–antiquark pair is spontaneously produced, turning the initial hadron into a pair of hadrons instead of isolating a color charge. Although ...
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