Curtis Gove Callan Jr. (born October 11, 1942) is an American theoretical

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate caus ...

and the James S. McDonnell Distinguished University Professor of Physics at

Princeton University Princeton University is a private university, private research university in Princeton, New Jersey. Founded in 1746 in Elizabeth, New Jersey, Elizabeth as the College of New Jersey, Princeton is the List of Colonial Colleges, fourth-oldest ins ...

. He has conducted research in

gauge theory In physics, a gauge theory is a type of field theory in which the Lagrangian (and hence the dynamics of the system itself) does not change (is invariant) under local transformations according to certain smooth families of operations (Lie groups) ...

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 ...

instanton An instanton (or pseudoparticle) is a notion appearing in theoretical and mathematical physics. An instanton is a classical solution to equations of motion with a finite, non-zero action, either in quantum mechanics or in quantum field theory. Mo ...

black hole A black hole is a region of spacetime where gravitation, gravity is so strong that nothing, including light or other Electromagnetic radiation, electromagnetic waves, has enough energy to escape it. The theory of general relativity predicts t ...

strong interaction The strong interaction or strong force is a fundamental interaction that confines quarks into proton, neutron, and other hadron particles. The strong interaction also binds neutrons and protons to create atomic nuclei, where it is called the n ...

s, and many other topics. He was awarded the

Sakurai Prize The J. J. Sakurai Prize for Theoretical Particle Physics, is presented by the American Physical Society at its annual April Meeting, and honors outstanding achievement in particle physics theory. The prize consists of a monetary award ($10,000 U ...

in 2000 ("For his classic formulation of the

renormalization group 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 ...

, his contributions to instanton physics and to the theory of monopoles and strings") and the

Dirac Medal The Dirac Medal is the name of four awards in the field of theoretical physics, computational chemistry, and mathematics, awarded by different organizations, named in honour of Professor Paul Dirac, one of the great theoretical physicists of the 20 ...

in 2004.

Biography

Callan received his B.Sc. in physics from

Haverford College Haverford College ( ) is a private liberal arts college in Haverford, Pennsylvania. It was founded as a men's college in 1833 by members of the Religious Society of Friends (Quakers), began accepting non-Quakers in 1849, and became coeducational ...

. He then pursued graduate studies in physics at Princeton University, where he was a student under Sam Treiman. Callan received his

Ph.D. A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields. Because it is a ...

in physics in 1964 after completing a doctoral dissertation titled "Spherically symmetric cosmological models." His Ph.D. students include

Vijay Balasubramanian Vijay Balasubramanian (born 1969) is a theoretical physicist and the Cathy and Marc Lasry Professor of Physics and Astronomy at the University of Pennsylvania. He has conducted research in string theory, quantum field theory, and biophysics (es ...

William E. Caswell William Edward Caswell (June 22, 1947 – September 11, 2001) was an American physicist who died during the September 11 attacks, as a passenger aboard American Airlines Flight 77, which was crashed into the The Pentagon, Pentagon. Caswell ...

Peter Woit Peter Woit (; born September 11, 1957) is an American theoretical physicist. He is a senior lecturer in the Mathematics department at Columbia University. Woit, a critic of string theory, has published a book ''Not Even Wrong'' (2006) and writ ...

Igor Klebanov Igor R. Klebanov (russian: И́горь Ромáнович Клеба́нов; uk, Ігор Романович Клєбанов; born March 29, 1962) is an American theoretical physicist. Since 1989, he has been a faculty member at Princeton Un ...

and

Juan Maldacena Juan Martín Maldacena (born September 10, 1968) is an Argentine theoretical physicist and the Carl P. Feinberg Professor in the School of Natural Sciences at the Institute for Advanced Study, Princeton. He has made significant contributions to t ...

. Callan is best known for his work on broken

scale invariance In physics, mathematics and statistics, scale invariance is a feature of objects or laws that do not change if scales of length, energy, or other variables, are multiplied by a common factor, and thus represent a universality. The technical term ...

(

Callan–Symanzik equation In physics, the Callan–Symanzik equation is a differential equation describing the evolution of the ''n''-point correlation functions under variation of the energy scale at which the theory is defined and involves the beta function of the theo ...

) and has also made leading contributions to

quantum field theory In theoretical physics, quantum field theory (QFT) is a theoretical framework that combines classical field theory, special relativity, and quantum mechanics. QFT is used in particle physics to construct physical models of subatomic particles and ...

and

in the areas of

dyon In physics, a dyon is a hypothetical particle in 4-dimensional theories with both electric and magnetic charges. A dyon with a zero electric charge is usually referred to as a magnetic monopole. Many grand unified theories predict the existence of ...

fermion In particle physics, a fermion is a particle that follows Fermi–Dirac statistics. Generally, it has a half-odd-integer spin: spin , spin , etc. In addition, these particles obey the Pauli exclusion principle. Fermions include all quarks an ...

dynamics, string

soliton In mathematics and physics, a soliton or solitary wave is a self-reinforcing wave packet that maintains its shape while it propagates at a constant velocity. Solitons are caused by a cancellation of nonlinear and dispersive effects in the medium ...

s and black holes. Callan has been a member of the

JASON defense advisory group JASON is an independent group of elite scientists which advises the United States government on matters of science and technology, mostly of a sensitive nature. The group was created in the aftermath of the Sputnik launch as a way to reinvigorate ...

since 1968, and was chair of the group from 1990 to 1995. He served as president 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 ...

(APS) in 2010. He was elected a Fellow of the APS in 1971. Callan was elected as a member of the

American Academy of Arts and Sciences The American Academy of Arts and Sciences (abbreviation: AAA&S) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, and ...

in 1987 and as a member of the

National Academy of Sciences The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the Nati ...

in 1989.

References

External links

Research page
at Princeton. * * Callan'
publications on INSPIRE-HEP
{{DEFAULTSORT:Callan, Curtis American string theorists 1942 births Living people Fellows of the American Physical Society J. J. Sakurai Prize for Theoretical Particle Physics recipients Members of the United States National Academy of Sciences Members of JASON (advisory group) Princeton University alumni Haverford College alumni Trustees of the Institute for Advanced Study 21st-century American physicists 20th-century American physicists Presidents of the American Physical Society