Steven C. Frautschi (; born December 6, 1933) is an American theoretical physicist, currently professor of physics emeritus at the California Institute of Technology (Caltech). He is known principally for his contributions to the

bootstrap theory Bootstrapping is a self-starting process that is supposed to proceed without external input. Bootstrapping, bootstrap, or bootstraps may also refer to: * Bootstrap (front-end framework), a free collection of tools for creating websites and web ...

of the strong interactions and for his contribution to the resolution of the infrared divergence problem in quantum electrodynamics (QED). He was named a Fellow of the

American Physical Society The American Physical Society (APS) is a not-for-profit membership organization of professionals in physics and related disciplines, comprising nearly fifty divisions, sections, and other units. Its mission is the advancement and diffusion of k ...

in 2015 for "contributions to the introduction of Regge poles into particle physics, elucidation of the role of infrared photons in high energy scattering, and for seminal contributions to undergraduate physics education".

Education and employment

Frautschi graduated from Harvard College in 1954 and received his PhD from

Stanford University Stanford University, officially Leland Stanford Junior University, is a private research university in Stanford, California. The campus occupies , among the largest in the United States, and enrolls over 17,000 students. Stanford is consider ...

in 1958, having written his dissertation on '' PC conservation in strong interactions and wide angle pair production and quantum electrodynamics at small distances'', under the supervision of

Sidney Drell Sidney David Drell (September 13, 1926 – December 21, 2016) was an American theoretical physicist and arms control expert. At the time of his death, he was professor emeritus at the Stanford Linear Accelerator Center (SLAC) and senior fello ...

. Frautschi worked as a postdoctoral researcher in the groups of Hideki Yukawa at

Kyoto University , mottoeng = Freedom of academic culture , established = , type = National university, Public (National) , endowment = ¥ 316 billion (2.4 1000000000 (number), billion USD) , faculty = 3,480 (Teaching Staff) , administrative_staff ...

and later of

Geoffrey Chew Geoffrey Foucar Chew (; June 5, 1924 – April 12, 2019) was an American theoretical physicist. He is known for his bootstrap theory of strong interactions. Life Chew worked as a professor of physics at the UC Berkeley since 1957 and was an e ...

at the University of California, Berkeley. He was an assistant professor at Cornell University before moving to Caltech in 1962. At Caltech he was the Executive Officer for Physics in 1988-97, and Master of Student Houses in 1997-2002. He received the Feynman Prize for Excellence in Teaching in 2014.

Work

Subjects of his works

In 1961, Chew and Frautschi discovered that the mesons fall into straight-line Regge trajectories (in their scheme,

spin Spin or spinning most often refers to: * Spinning (textiles), the creation of yarn or thread by twisting fibers together, traditionally by hand spinning * Spin, the rotation of an object around a central axis * Spin (propaganda), an intentionally b ...

is plotted against mass squared on a so-called Chew–Frautschi plot), and the two of them introduced the

pomeron In physics, the pomeron is a Regge trajectory — a family of particles with increasing spin — postulated in 1961 to explain the slowly rising cross section of hadronic collisions at high energies. It is named after Isaak Pomeranchuk. Overview W ...

into the western literature. Frautschi's most well known contribution to strong-interaction theory was the statistical bootstrap, a prediction that the number of hadronic states grows exponentially with energy. This is nowadays understood as a manifestation of the deconfinement phase transition. The exponential growth is incorporated into

string theory In physics, string theory is a theoretical framework in which the point-like particles of particle physics are replaced by one-dimensional objects called strings. String theory describes how these strings propagate through space and interac ...

, where it is known as the

Hagedorn temperature The Hagedorn temperature, ''T''H, is the temperature in theoretical physics where hadronic matter (i.e. ordinary matter) is no longer stable, and must either "evaporate" or convert into quark matter; as such, it can be thought of as the "boiling po ...

. (This S-matrix approach to the strong interactions was largely abandoned by the particle physics community in the 1970s in light of

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 ...

.) In 1961, with

Donald R. Yennie Donald Robert Yennie (March 4, 1924 – April 14, 1993) was an American theoretical physicist and professor at Cornell University. He is known for his work on renormalization in quantum electrodynamics and for early work on the structure of nu ...

and Hiroshi Suura, he elucidated the role of infrared photons properly summed in high-energy QED. This work was one of the keys to solving the problem of infrared divergences in gauge theories. One of Frautschi's doctoral students at Caltech was Roger Dashen.

Publications

* 1982 Entropy in an Expanding Universe. ''Science'' 13/08/1982: Vol. 217, Issue 4560, pp. 593–599 ( DOI: 10.1126/science.217.4560.593)Science Mag
/ref> * 1986 ''The Mechanical Universe, Mechanics and Heat'', Advanced Edition, textbook (Steven C. Frautschi, Richard P. Olenick, Tom M. Apostol, David L. Goodstein). New York: Cambridge University Press (1st pbk. ed. 2008).

Family

His daughters, Jennifer and Laura, are both professional violinists.

References

{{DEFAULTSORT:Frautschi, Steven 1933 births Living people 21st-century American physicists California Institute of Technology faculty Theoretical physicists Harvard College alumni Stanford University alumni Fellows of the American Physical Society