Howard Georgi

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Howard Georgi
Born
Howard Mason Georgi III

(1947-01-06) 6 January 1947 (age 76)
Alma mater
Known for
Awards
Scientific career
Fields
Institutions
Doctoral advisor Charles M. Sommerfield
Doctoral students

Howard Mason Georgi III (born January 6, 1947) is an American theoretical physicist and the Mallinckrodt Professor of Physics and Harvard College Professor at Harvard University. [1] He is also director of undergraduate studies in physics. He was co-master and then faculty dean of Leverett House with his wife, Ann Blake Georgi, from 1998 to 2018. His early work was in Grand Unification and gauge coupling unification within SU(5) and SO(10) groups (see Georgi–Glashow model).

Contents

Education

Georgi graduated from Pingry School in 1964, [2] graduated from Harvard College in 1967 and obtained his Ph.D. from Yale University in 1971. [1] He was junior fellow in the Harvard Society of Fellows from 1973–76 and a senior fellow from 1982-1998. [1]

Career

In early 1974 Georgi (with Sheldon Glashow) published the first grand unified theory (GUT), the Minimal SU(5) Georgi–Glashow model. [3] Georgi independently (alongside Harald Fritzsch and Peter Minkowski) published a minimal SO(10) GUT model in 1974. [4]

Georgi proposed an SU(5) GUT model with softly broken supersymmetry with Savas Dimopoulos in 1981. This paper is one of the foundational works for the supersymmetric Standard Model (MSSM). After the measurements of the three Standard Model gauge couplings at LEP I in 1991, it was shown that particle content of the MSSM, in contrast to the Standard Model alone, led to precision gauge coupling unification.

He has since worked on several different areas of physics including composite Higgs models, heavy quark effective theory, dimensional deconstruction, little Higgs, [5] and unparticle theories.

Unparticle physics is a theory that there exists matter that cannot be explained in terms of particles, because its components are scale invariant. Howard Georgi proposed this theory in the spring of 2007 in the papers "Unparticle Physics" and "Another Odd Thing About Unparticle Physics". [6] [7]

Together with Vadim Kuzmin, Georgi received the Pomeranchuk Prize of the Alikhanov Institute for Theoretical and Experimental Physics (ITEP) in 2006. [5]

Georgi has published several books, one of which is Lie Algebras in Particle Physics published by World Scientific. He has also published The Physics of Waves and Weak Interactions and Modern Particle Theory.

Honors

In 1995 he was elected to the National Academy of Sciences [1] and received the Sakurai Prize; in 2000 he shared the Dirac Medal with Jogesh Pati and Helen Quinn. [8]

Related Research Articles

In physics, the fundamental interactions or fundamental forces are the interactions that do not appear to be reducible to more basic interactions. There are four fundamental interactions known to exist:

<span class="mw-page-title-main">Grand Unified Theory</span> Any particle physics model that theorizes the merging of the electromagnetic, weak and strong forces

Grand Unified Theory (GUT) is any model in particle physics that merges the electromagnetic, weak, and strong forces into a single force at high energies. Although this unified force has not been directly observed, many GUT models theorize its existence. If the unification of these three interactions is possible, it raises the possibility that there was a grand unification epoch in the very early universe in which these three fundamental interactions were not yet distinct.

<span class="mw-page-title-main">Proton decay</span> Hypothetical particle decay process of a proton

In particle physics, proton decay is a hypothetical form of particle decay in which the proton decays into lighter subatomic particles, such as a neutral pion and a positron. The proton decay hypothesis was first formulated by Andrei Sakharov in 1967. Despite significant experimental effort, proton decay has never been observed. If it does decay via a positron, the proton's half-life is constrained to be at least 1.67×1034 years.

<span class="mw-page-title-main">Standard Model</span> Theory of forces and subatomic particles

The Standard Model of particle physics is the theory describing three of the four known fundamental forces in the universe and classifying all known elementary particles. It was developed in stages throughout the latter half of the 20th century, through the work of many scientists worldwide, with the current formulation being finalized in the mid-1970s upon experimental confirmation of the existence of quarks. Since then, proof of the top quark (1995), the tau neutrino (2000), and the Higgs boson (2012) have added further credence to the Standard Model. In addition, the Standard Model has predicted various properties of weak neutral currents and the W and Z bosons with great accuracy.

<span class="mw-page-title-main">Georgi–Glashow model</span> Grand Unified Theory proposed in 1974

In particle physics, the Georgi–Glashow model is a particular Grand Unified Theory (GUT) proposed by Howard Georgi and Sheldon Glashow in 1974. In this model, the Standard Model gauge groups SU(3) × SU(2) × U(1) are combined into a single simple gauge group SU(5). The unified group SU(5) is then thought to be spontaneously broken into the Standard Model subgroup below a very high energy scale called the grand unification scale.

<span class="mw-page-title-main">Sheldon Glashow</span> American theoretical physicist

Sheldon Lee Glashow is a Nobel Prize-winning American theoretical physicist. He is the Metcalf Professor of Mathematics and Physics at Boston University and Eugene Higgins Professor of Physics, emeritus, at Harvard University, and is a member of the board of sponsors for the Bulletin of the Atomic Scientists.

<span class="mw-page-title-main">Gauge boson</span> Elementary particles that are force carriers

In particle physics, a gauge boson is a bosonic elementary particle that acts as the force carrier for elementary fermions. Elementary particles whose interactions are described by a gauge theory interact with each other by the exchange of gauge bosons, usually as virtual particles.

<span class="mw-page-title-main">Minimal Supersymmetric Standard Model</span> Simplest supersymmetric extension to the Standard Model

The Minimal Supersymmetric Standard Model (MSSM) is an extension to the Standard Model that realizes supersymmetry. MSSM is the minimal supersymmetrical model as it considers only "the [minimum] number of new particle states and new interactions consistent with "Reality". Supersymmetry pairs bosons with fermions, so every Standard Model particle has a superpartner yet undiscovered. If discovered, such superparticles could be candidates for dark matter, and could provide evidence for grand unification or the viability of string theory. The failure to find evidence for MSSM using the Large Hadron Collider has strengthened an inclination to abandon it.

In physics, a unified field theory (UFT) is a type of field theory that allows all that is usually thought of as fundamental forces and elementary particles to be written in terms of a pair of physical and virtual fields. According to modern discoveries in physics, forces are not transmitted directly between interacting objects but instead are described and interpreted by intermediary entities called fields.

Jogesh C. Pati is an Indian-American theoretical physicist at the SLAC National Accelerator Laboratory.

<span class="mw-page-title-main">SO(10)</span>

In particle physics, SO(10) refers to a grand unified theory (GUT) based on the spin group Spin(10). The shortened name SO(10) is conventional among physicists, and derives from the Lie algebra or less precisely the Lie group of SO(10), which is a special orthogonal group that is double covered by Spin(10).

In particle physics, little Higgs models are based on the idea that the Higgs boson is a pseudo-Goldstone boson arising from some global symmetry breaking at a TeV energy scale. The goal of little Higgs models is to use the spontaneous breaking of such approximate global symmetries to stabilize the mass of the Higgs boson(s) responsible for electroweak symmetry breaking.

<span class="mw-page-title-main">Split supersymmetry</span> Particle physics theory

In particle physics, split supersymmetry is a proposal for physics beyond the Standard Model.

Savas Dimopoulos is a particle physicist at Stanford University. He worked at CERN from 1994 to 1997. Dimopoulos is well known for his work on constructing theories beyond the Standard Model.

Isaak Yakovlevich Pomeranchuk was a Soviet physicist of Polish origin in the former Soviet program of nuclear weapons. His career in physics spent mostly studying the particle physics, quantum field theory, electromagnetic and synchrotron radiation, condensed matter physics and the physics of liquid helium.

<span class="mw-page-title-main">Physics beyond the Standard Model</span> Theories trying to extend known physics

Physics beyond the Standard Model (BSM) refers to the theoretical developments needed to explain the deficiencies of the Standard Model, such as the inability to explain the fundamental parameters of the standard model, the strong CP problem, neutrino oscillations, matter–antimatter asymmetry, and the nature of dark matter and dark energy. Another problem lies within the mathematical framework of the Standard Model itself: the Standard Model is inconsistent with that of general relativity, and one or both theories break down under certain conditions, such as spacetime singularities like the Big Bang and black hole event horizons.

In the Grand Unified Theory of particle physics (GUT), the desert refers to a theorized gap in energy scales, between approximately the electroweak energy scale–conventionally defined as roughly the vacuum expectation value or VeV of the Higgs field –and the GUT scale, in which no unknown interactions appear.

<span class="mw-page-title-main">John Iliopoulos</span> Greek physicist

John (Jean) Iliopoulos is a Greek physicist. He is the first person to present the Standard Model of particle physics in a single report. He is best known for his prediction of the charm quark with Sheldon Glashow and Luciano Maiani. Iliopoulos is also known for demonstrating the cancellation of anomalies in the Standard model. He is further known for the Fayet-Iliopoulos D-term formula, which was introduced in 1974. He is currently an honorary member of Laboratory of theoretical physics of École Normale Supérieure, Paris.

In theoretical physics, a mass generation mechanism is a theory that describes the origin of mass from the most fundamental laws of physics. Physicists have proposed a number of models that advocate different views of the origin of mass. The problem is complicated because the primary role of mass is to mediate gravitational interaction between bodies, and no theory of gravitational interaction reconciles with the currently popular Standard Model of particle physics.

Ali H. Chamseddine is a Lebanese physicist known for his contributions to particle physics, general relativity and mathematical physics. As of 2013, Chamseddine is a physics Professor at the American University of Beirut and the Institut des hautes études scientifiques.

References

  1. 1 2 3 4 5 "Howard Georgi". American Institute of Physics, Center for History of Physics. Archived from the original on March 6, 2016. Retrieved June 11, 2013.
  2. Class Notes, The Pingry Review, Summer 2012. Accessed March 14, 2022. "1964... Howard Georgi writes, 'Still teaching physics at Harvard'"
  3. Georgi, Howard & Glashow, Sheldon (1974). "Unity of All Elementary-Particle Forces". Physical Review Letters. 32 (8): 438
  4. Howard Georgi, "The state of the art—gauge theories" Particles and Fields 1974, ed. Carl E. Carlson
  5. 1 2 "Pomeranchuk Prize Winners 2006". Alikhanov Institute for Theoretical and Experimental Physics (ITEP). Archived from the original on February 24, 2016. Retrieved June 11, 2013.
  6. Howard Georgi, "Unparticle Physics", 23 March 2007 (accessed 29 January 2007).
  7. Howard Georgi, "Another Odd Thing About Unparticle Physics", 19 April 2008 (accessed 29 January 2008).
  8. "Dirac Medallists 2000". Abdus Salam International Centre for Theoretical Physics. Retrieved June 11, 2013.