Franz Wegner

Last updated

Franz Wegner
Born (1940-06-15) 15 June 1940 (age 83)
Alma mater Forschungszentrum Jülich
Technical University Munich
Known for Lattice gauge theory
Wegner exponent
Wegner estimate
Wegner orbital model
Awards Lars Onsager Prize (2015)
Max Planck medal (1986)
Walter Schottky Prize (1976)
Scientific career
Fields Statistical Physics
Institutions University of Heidelberg
Brown University
Doctoral advisor Wilhelm Brenig
Other academic advisors Leo Kadanoff
Herbert Wagner

Franz Joachim Wegner (born 15 June 1940) is emeritus professor for theoretical physics at the University of Heidelberg.

Contents

Education

Franz Wegner attained a doctorate in 1968 with thesis advisor Wilhelm Brenig at the Technical University Munich with the thesis, "Zum Heisenberg-Modell im paramagnetischen Bereich und am kritischen Punkt" ("On the Heisenberg model within the paramagnetic range and at the critical point").

Subsequently, he did research with a post-doctoral position at Forschungszentrum Jülich, in the group of Herbert Wagner and at Brown University with Leo Kadanoff. [1] Since 1974 he is a professor at Heidelberg. [2]

Research

The emphasis of Wegner's scientific work is statistical physics, in particular the theory of phase transitions and the renormalization group. [3] [4] The eponymous "Wegner exponent" is of fundamental importance for the purpose of describing corrections to asymptotic scale invariance in close proximity to phase transitions. Wegner also "invented" the foundational lattice gauge theoretical models. The method developed from Wegner's foundational work is nowadays intensively used in simulations of quantum chromodynamics.

Accolades

Wegner won the Walter Schottky prize in 1976 for his work on phase transitions and elementary particles. [2] He has also been elected to the Heidelberger Academy of Sciences and won the Max Planck medal among other awards and recognitions. He won the Lars Onsager prize from American Physical Society in 2015 for his contributions to Statistical mechanics. [5]

Selected works of Wegner

Reprinted in Claudio Rebbi (ed.), Lattice Gauge Theories and Monte Carlo Simulations, World Scientific, Singapore (1983), p. 60–73. (Abstract.)

See also

Related Research Articles

<span class="mw-page-title-main">Condensed matter physics</span> Branch of physics dealing with a property of matter

Condensed matter physics is the field of physics that deals with the macroscopic and microscopic physical properties of matter, especially the solid and liquid phases which arise from electromagnetic forces between atoms. More generally, the subject deals with condensed phases of matter: systems of many constituents with strong interactions among them. More exotic condensed phases include the superconducting phase exhibited by certain materials at extremely low cryogenic temperature, the ferromagnetic and antiferromagnetic phases of spins on crystal lattices of atoms, and the Bose–Einstein condensate found in ultracold atomic systems. Condensed matter physicists seek to understand the behavior of these phases by experiments to measure various material properties, and by applying the physical laws of quantum mechanics, electromagnetism, statistical mechanics, and other physics theories to develop mathematical models.

In theoretical physics, the term renormalization group (RG) refers to a formal apparatus that allows systematic investigation of the changes of a physical system as viewed at different scales. In particle physics, it reflects the changes in the underlying force laws as the energy scale at which physical processes occur varies, energy/momentum and resolution distance scales being effectively conjugate under the uncertainty principle.

<span class="mw-page-title-main">Kenneth G. Wilson</span> American theoretical physicist (1936–2013)

Kenneth Geddes "Ken" Wilson was an American theoretical physicist and a pioneer in leveraging computers for studying particle physics. He was awarded the 1982 Nobel Prize in Physics for his work on phase transitions—illuminating the subtle essence of phenomena like melting ice and emerging magnetism. It was embodied in his fundamental work on the renormalization group.

<span class="mw-page-title-main">Lattice gauge theory</span> Theory of quantum gauge fields on a lattice

In physics, lattice gauge theory is the study of gauge theories on a spacetime that has been discretized into a lattice.

<span class="mw-page-title-main">Hagen Kleinert</span> German physicist

Hagen Kleinert is professor of theoretical physics at the Free University of Berlin, Germany , Honorary Doctor at the West University of Timișoara, and at the Kyrgyz-Russian Slavic University in Bishkek. He is also Honorary Member of the Russian Academy of Creative Endeavors. For his contributions to particle and solid-state physics he was awarded the Max Born Prize 2008 with Medal. His contribution to the memorial volume celebrating the 100th birthday of Lev Davidovich Landau earned him the Majorana Prize 2008 with Medal. He is married to Dr. Annemarie Kleinert since 1974 with whom he has a son Michael Kleinert.

Critical exponents describe the behavior of physical quantities near continuous phase transitions. It is believed, though not proven, that they are universal, i.e. they do not depend on the details of the physical system, but only on some of its general features. For instance, for ferromagnetic systems, the critical exponents depend only on:

<span class="mw-page-title-main">History of quantum field theory</span>

In particle physics, the history of quantum field theory starts with its creation by Paul Dirac, when he attempted to quantize the electromagnetic field in the late 1920s. Heisenberg was awarded the 1932 Nobel Prize in Physics "for the creation of quantum mechanics". Major advances in the theory were made in the 1940s and 1950s, leading to the introduction of renormalized quantum electrodynamics (QED). QED was so successful and accurately predictive that efforts were made to apply the same basic concepts for the other forces of nature. By the late 1970s, these efforts successfully utilized gauge theory in the strong nuclear force and weak nuclear force, producing the modern Standard Model of particle physics.

<span class="mw-page-title-main">Topological order</span> Type of order at absolute zero

In physics, topological order is a kind of order in the zero-temperature phase of matter. Macroscopically, topological order is defined and described by robust ground state degeneracy and quantized non-Abelian geometric phases of degenerate ground states. Microscopically, topological orders correspond to patterns of long-range quantum entanglement. States with different topological orders cannot change into each other without a phase transition.

Quantum metrology is the study of making high-resolution and highly sensitive measurements of physical parameters using quantum theory to describe the physical systems, particularly exploiting quantum entanglement and quantum squeezing. This field promises to develop measurement techniques that give better precision than the same measurement performed in a classical framework. Together with quantum hypothesis testing, it represents an important theoretical model at the basis of quantum sensing.

In physics, the Bethe ansatz is an ansatz for finding the exact wavefunctions of certain quantum many-body models, most commonly for one-dimensional lattice models. It was first used by Hans Bethe in 1931 to find the exact eigenvalues and eigenvectors of the one-dimensional antiferromagnetic isotropic (XXX) Heisenberg model.

A charge density wave (CDW) is an ordered quantum fluid of electrons in a linear chain compound or layered crystal. The electrons within a CDW form a standing wave pattern and sometimes collectively carry an electric current. The electrons in such a CDW, like those in a superconductor, can flow through a linear chain compound en masse, in a highly correlated fashion. Unlike a superconductor, however, the electric CDW current often flows in a jerky fashion, much like water dripping from a faucet due to its electrostatic properties. In a CDW, the combined effects of pinning and electrostatic interactions likely play critical roles in the CDW current's jerky behavior, as discussed in sections 4 & 5 below.

<span class="mw-page-title-main">Subir Sachdev</span> Indian physicist

Subir Sachdev is Herchel Smith Professor of Physics at Harvard University specializing in condensed matter. He was elected to the U.S. National Academy of Sciences in 2014, and received the Lars Onsager Prize from the American Physical Society and the Dirac Medal from the ICTP in 2018. He was a co-editor of the Annual Review of Condensed Matter Physics from 2017–2019.

<span class="mw-page-title-main">Piers Coleman</span> British-American physicist

Piers Coleman is a British-born theoretical physicist, working in the field of theoretical condensed matter physics. Coleman is professor of physics at Rutgers University in New Jersey and at Royal Holloway, University of London.

In condensed matter physics, a quantum spin liquid is a phase of matter that can be formed by interacting quantum spins in certain magnetic materials. Quantum spin liquids (QSL) are generally characterized by their long-range quantum entanglement, fractionalized excitations, and absence of ordinary magnetic order.

Roderich Moessner is a theoretical physicist at the Max Planck Institute for the Physics of Complex Systems in Dresden, Germany. His research interests are in condensed matter and materials physics, especially concerning new and topological forms of order, as well as the study of classical and quantum many-body dynamics in and out of equilibrium.

Dieter Vollhardt is a German physicist and Professor of Theoretical Physics at the University of Augsburg.

Jean Zinn-Justin is a French theoretical physicist.

Shang-keng Ma was a Chinese theoretical physicist, known for his work on the theory of critical phenomena and random systems. He is known as the co-author with Bertrand Halperin and Pierre Hohenberg of a 1972 paper that "generalized the renormalization group theory to dynamical critical phenomena." Ma is also known as the co-author with Yoseph Imry of a 1975 paper and with Amnon Aharony and Imry of a 1976 paper that established the foundation of the random field Ising model (RFIM)

Alan Harold Luther is an American physicist, specializing in condensed matter physics.

<span class="mw-page-title-main">Germán Sierra</span> Spanish theoretical physicist, author, and academic

Germán Sierra is a Spanish theoretical physicist, author, and academic. He is Professor of Research at the Institute of Theoretical Physics Autonomous University of Madrid-Spanish National Research Council.

References

  1. Kadanoff, L. P.; Wegner, F. J. (1971). "Some Critical Properties of the Eight-Vertex Model". Phys. Rev. B. 4 (11): 3989–93. Bibcode:1971PhRvB...4.3989K. doi:10.1103/PhysRevB.4.3989.
  2. 1 2 "German Physical Society gives theoretical‐physics awards", Physics Today , 29 (9): 69, 1976, Bibcode:1976PhT....29i..69., doi:10.1063/1.3023914 .
  3. Kadanoff, Leo P. (1999), From order to chaos II: essays, critical, chaotic, and otherwise, Series on Nonlinear Science, vol. 32, World Scientific, p. 161, ISBN   978-981-02-3434-8 .
  4. Cao, Tian Yu (2004), Conceptual Foundations of Quantum Field Theory, Cambridge University Press, p. 93, ISBN   978-0-521-60272-3 .
  5. "Prize Recipient". aps.org. Retrieved 30 January 2018.