John Clayton Taylor (born 4 August 1930) is a British

mathematical physicist Mathematical physics refers to the development of mathematical methods for application to problems in physics. The ''Journal of Mathematical Physics'' defines the field as "the application of mathematics to problems in physics and the developmen ...

. He is an Emeritus Professor of Mathematical Physics at the

Department of Applied Mathematics and Theoretical Physics Department may refer to: * Departmentalization, division of a larger organization into parts with specific responsibility Government and military *Department (administrative division), a geographical and administrative division within a country, ...

of the

University of Cambridge , mottoeng = Literal: From here, light and sacred draughts. Non literal: From this place, we gain enlightenment and precious knowledge. , established = , other_name = The Chancellor, Masters and Schola ...

and an Emeritus Fellow of

Robinson College Robinson College is a constituent college of the University of Cambridge. Founded in 1977, it is one of the newest Oxbridge colleges and is unique in having been intended, from its inception, for both undergraduate and graduate students of bo ...

. He is the father of mathematician Richard Taylor.

Education

Taylor earned his PhD from the

in 1956, under the supervision of Richard J. Eden and

Abdus Salam Mohammad Abdus Salam Salam adopted the forename "Mohammad" in 1974 in response to the anti-Ahmadiyya decrees in Pakistan, similarly he grew his beard. (; ; 29 January 192621 November 1996) was a Punjabi Pakistani theoretical physicist and a ...

. His thesis was entitled ''Renormalisation and Related Topics in Quantum Field Theory''.British Library EthOS
Retrieved 2016-03-22.

Research

Taylor has made 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 the physics of

elementary particle In particle physics, an elementary particle or fundamental particle is a subatomic particle that is not composed of other particles. Particles currently thought to be elementary include electrons, the fundamental fermions ( quarks, leptons, an ...

s. His contributions include: the discovery (also made independently by

Lev Landau Lev Davidovich Landau (russian: Лев Дави́дович Ланда́у; 22 January 1908 – 1 April 1968) was a Soviet- Azerbaijani physicist of Jewish descent who made fundamental contributions to many areas of theoretical physics. His a ...

) of singularities in the analytical structure of the

Feynman integral The path integral formulation is a description in quantum mechanics that generalizes the action principle of classical mechanics. It replaces the classical notion of a single, unique classical trajectory for a system with a sum, or functional i ...

s for processes in quantum field theory, the PCAC nature of radioactive decay of the pion and the discovery in 1971 of the so-called

Slavnov–Taylor identities In quantum field theory, a Slavnov–Taylor identity is the non-Abelian generalisation of a Ward–Takahashi identity, which in turn is an identity between correlation functions that follows from the global or gauged symmetries of a theory, and ...

, which control

symmetry Symmetry (from grc, συμμετρία "agreement in dimensions, due proportion, arrangement") in everyday language refers to a sense of harmonious and beautiful proportion and balance. In mathematics, "symmetry" has a more precise definit ...

and

renormalisation Renormalization is a collection of techniques in quantum field theory, the statistical mechanics of fields, and the theory of self-similarity, self-similar geometric structures, that are used to treat infinity, infinities arising in calculated ...

gauge theories 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 ...

. With various collaborators, in 1980 he discovered that real and virtual

infrared divergence In physics, an infrared divergence (also IR divergence or infrared catastrophe) is a situation in which an integral, for example a Feynman diagram, diverges because of contributions of objects with very small energy approaching zero, or equivalent ...

s do not cancel in

QCD 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 o ...

as they do in QED. They also showed how these infrared divergences exponentiate. In addition, they contributed to the

resummation In mathematics and theoretical physics, resummation is a procedure to obtain a finite result from a divergent sum (series) of functions. Resummation involves a definition of another (convergent) function in which the individual terms defining th ...

programme in thermal QCD, simplifying the "hard" part of the

effective action In quantum field theory, the quantum effective action is a modified expression for the classical action taking into account quantum corrections while ensuring that the principle of least action applies, meaning that extremizing the effective act ...

. Later, they studied complications arising from the non-polynomial nature of the QCD

Hamiltonian Hamiltonian may refer to: * Hamiltonian mechanics, a function that represents the total energy of a system * Hamiltonian (quantum mechanics), an operator corresponding to the total energy of that system ** Dyall Hamiltonian, a modified Hamiltonian ...

in the (

unitary Unitary may refer to: Mathematics * Unitary divisor * Unitary element * Unitary group * Unitary matrix * Unitary morphism * Unitary operator * Unitary transformation * Unitary representation * Unitarity (physics) * ''E''-unitary inverse semigroup ...

)

Coulomb gauge In the physics of gauge theories, gauge fixing (also called choosing a gauge) denotes a mathematical procedure for coping with redundant degrees of freedom in field variables. By definition, a gauge theory represents each physically distinct co ...

Books

Gauge Theories of Weak Interactions
(1976)
Hidden Unity in Nature's Laws
(2001)
Gauge Theories in the Twentieth Century
(2001)

Awards and honours

Taylor was elected a Fellow of the Royal Society (FRS) in 1981. One or more of the preceding sentences may incorporate text from the royalsociety.org website where "all text published under the heading 'Biography' on Fellow profile pages is available under Creative Commons Attribution 4.0 International License." His certificate of election reads:

References

{{DEFAULTSORT:Taylor, John Clayton 1930 births Living people Fellows of Robinson College, Cambridge Fellows of the Royal Society British mathematicians British physicists