John Moffat
Encyclopedia
John W. Moffat is a Professor Emeritus
Emeritus
Emeritus is a post-positive adjective that is used to designate a retired professor, bishop, or other professional or as a title. The female equivalent emerita is also sometimes used.-History:...

 in physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...

 at the University of Toronto
University of Toronto
The University of Toronto is a public research university in Toronto, Ontario, Canada, situated on the grounds that surround Queen's Park. It was founded by royal charter in 1827 as King's College, the first institution of higher learning in Upper Canada...

.
He is also an adjunct Professor in physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...

 at the University of Waterloo
University of Waterloo
The University of Waterloo is a comprehensive public university in the city of Waterloo, Ontario, Canada. The school was founded in 1957 by Drs. Gerry Hagey and Ira G. Needles, and has since grown to an institution of more than 30,000 students, faculty, and staff...

 and a resident affiliate member of the Perimeter Institute for Theoretical Physics
Perimeter Institute for Theoretical Physics
Perimeter Institute for Theoretical Physics is an independent, resident-based research institute devoted to foundational issues in theoretical physics located in Waterloo, Ontario, Canada. Perimeter Institute was founded in 1999 by Mike Lazaridis...

.

Moffat is best known for his work on gravity and cosmology
Cosmology
Cosmology is the discipline that deals with the nature of the Universe as a whole. Cosmologists seek to understand the origin, evolution, structure, and ultimate fate of the Universe at large, as well as the natural laws that keep it in order...

, culminating in his nonsymmetric gravitational theory
Nonsymmetric gravitational theory
In theoretical physics, the nonsymmetric gravitational theory of John Moffat is a classical theory of gravitation which tries to explain the observation of the flat rotation curves of galaxies....

 and scalar–tensor–vector gravity (now called MOG), and summarized in his 2008 book for general readers, Reinventing Gravity. His theory explains galactic rotation curves without invoking dark matter
Dark matter
In astronomy and cosmology, dark matter is matter that neither emits nor scatters light or other electromagnetic radiation, and so cannot be directly detected via optical or radio astronomy...

. He proposes a variable speed of light
Variable speed of light
The variable speed of light concept states that the speed of light in a vacuum, usually denoted by c, may not be constant in most cases. In most situations in condensed matter physics when light is traveling through a medium, it effectively has a slower speed...

 approach to cosmological
Physical cosmology
Physical cosmology, as a branch of astronomy, is the study of the largest-scale structures and dynamics of the universe and is concerned with fundamental questions about its formation and evolution. For most of human history, it was a branch of metaphysics and religion...

 problems, which posits that G
Gravitational constant
The gravitational constant, denoted G, is an empirical physical constant involved in the calculation of the gravitational attraction between objects with mass. It appears in Newton's law of universal gravitation and in Einstein's theory of general relativity. It is also known as the universal...

/c is constant through time, but G and c separately have not been. Moreover, the speed of light
Speed of light
The speed of light in vacuum, usually denoted by c, is a physical constant important in many areas of physics. Its value is 299,792,458 metres per second, a figure that is exact since the length of the metre is defined from this constant and the international standard for time...

 c may have been much higher during early moments of the Big Bang
Big Bang
The Big Bang theory is the prevailing cosmological model that explains the early development of the Universe. According to the Big Bang theory, the Universe was once in an extremely hot and dense state which expanded rapidly. This rapid expansion caused the young Universe to cool and resulted in...

. His recent work on inhomogeneous cosmological models purports to explain certain anomalous effects in the CMB
CMB
CMB can mean:*The IATA airport code for Bandaranaike International Airport, Colombo – Sri Lanka's only international airport*C.M.B., the debut album of American R&B and pop group Color Me Badd...

 data, and to account for the recently discovered acceleration of the expansion of the universe.

Moffat has proposed a new nonlocal variant of quantum field theory
Quantum field theory
Quantum field theory provides a theoretical framework for constructing quantum mechanical models of systems classically parametrized by an infinite number of dynamical degrees of freedom, that is, fields and many-body systems. It is the natural and quantitative language of particle physics and...

, that is finite at all orders and hence dispenses with renormalization
Renormalization
In quantum field theory, the statistical mechanics of fields, and the theory of self-similar geometric structures, renormalization is any of a collection of techniques used to treat infinities arising in calculated quantities....

. It also generates mass without a Higgs mechanism
Higgs mechanism
In particle physics, the Higgs mechanism is the process in which gauge bosons in a gauge theory can acquire non-vanishing masses through absorption of Nambu-Goldstone bosons arising in spontaneous symmetry breaking....

.

An unusual start to a physics career

Moffat began life as a struggling artist, but gave up after living for a time in Paris with no income. Upon returning to Copenhagen
Copenhagen
Copenhagen is the capital and largest city of Denmark, with an urban population of 1,199,224 and a metropolitan population of 1,930,260 . With the completion of the transnational Øresund Bridge in 2000, Copenhagen has become the centre of the increasingly integrating Øresund Region...

, Denmark
Denmark
Denmark is a Scandinavian country in Northern Europe. The countries of Denmark and Greenland, as well as the Faroe Islands, constitute the Kingdom of Denmark . It is the southernmost of the Nordic countries, southwest of Sweden and south of Norway, and bordered to the south by Germany. Denmark...

, he became interested in the cosmos and began teaching himself mathematics and physics. He made such quick progress that within a year he began working on problems of general relativity
General relativity
General relativity or the general theory of relativity is the geometric theory of gravitation published by Albert Einstein in 1916. It is the current description of gravitation in modern physics...

 and unified field theory
Unified field theory
In physics, a unified field theory, occasionally referred to as a uniform field theory, 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 single field. There is no accepted unified field theory, and thus...

.

"When I was about 20, I wrote a letter to Albert Einstein telling him that I was working on one of his theories. In 1953 Einstein sent me a reply, from Princeton, New Jersey
Princeton, New Jersey
Princeton is a community located in Mercer County, New Jersey, United States. It is best known as the location of Princeton University, which has been sited in the community since 1756...

, but it was written in German. So I ran down to my barber shop (in Copenhagen) to have my barber translate it for me. Through that summer and fall, we exchanged about a half dozen letters. The local press picked up on these stories which then caught the attention of physicist Niels Bohr
Niels Bohr
Niels Henrik David Bohr was a Danish physicist who made foundational contributions to understanding atomic structure and quantum mechanics, for which he received the Nobel Prize in Physics in 1922. Bohr mentored and collaborated with many of the top physicists of the century at his institute in...

 and others. Suddenly doors of opportunity were swinging open for me". (Perimeter Institute for Theoretical Physics
Perimeter Institute for Theoretical Physics
Perimeter Institute for Theoretical Physics is an independent, resident-based research institute devoted to foundational issues in theoretical physics located in Waterloo, Ontario, Canada. Perimeter Institute was founded in 1999 by Mike Lazaridis...

, 2005)


In 1958, he became the only Trinity College
Trinity College, Cambridge
Trinity College is a constituent college of the University of Cambridge. Trinity has more members than any other college in Cambridge or Oxford, with around 700 undergraduates, 430 graduates, and over 170 Fellows...

, Cambridge
University of Cambridge
The University of Cambridge is a public research university located in Cambridge, United Kingdom. It is the second-oldest university in both the United Kingdom and the English-speaking world , and the seventh-oldest globally...

 student to be awarded a Ph.D. without a first degree. (He was supervised by Fred Hoyle
Fred Hoyle
Sir Fred Hoyle FRS was an English astronomer and mathematician noted primarily for his contribution to the theory of stellar nucleosynthesis and his often controversial stance on other cosmological and scientific matters—in particular his rejection of the "Big Bang" theory, a term originally...

 and Abdus Salam
Abdus Salam
Mohammad Abdus Salam, NI, SPk Mohammad Abdus Salam, NI, SPk Mohammad Abdus Salam, NI, SPk (Urdu: محمد عبد السلام, pronounced , (January 29, 1926– November 21, 1996) was a Pakistani theoretical physicist and Nobel laureate in Physics for his work on the electroweak unification of the...

.)



"Dear Professor . . . I would be eternally indebted if you could find time to read my work," he began.


“Most honorable Mr. Moffat: Our situation is the following. We are standing in front of a closed box which we cannot open, and we try hard to discuss what is inside and what is not,” Einstein replied.


During a career that spans over five decades, Moffat worked on a variety of subjects in Theoretical Physics
Theoretical physics
Theoretical physics is a branch of physics which employs mathematical models and abstractions of physics to rationalize, explain and predict natural phenomena...

. These include particle physics, quantum field theory, quantum gravity and cosmology.

Variable Speed of Light: Theory and Controversy

In 1992, John Moffat proposed that the speed of light was much larger in the early universe, in which the speed of light was 1030 times faster than its current value. He published his "variable speed of light
Variable speed of light
The variable speed of light concept states that the speed of light in a vacuum, usually denoted by c, may not be constant in most cases. In most situations in condensed matter physics when light is traveling through a medium, it effectively has a slower speed...

" (VSL) theory in two places—on the Los Alamos National Laboratory's (LANL) online archive, Nov. 16, 1992, and in a 1993 edition of the obscure International Journal of Modern Physics D.

The scientific community mostly ignored VSL theory until in 2001, University of New South Wales astronomer John Webb and peers detected experimental evidence from telescopic observations that the cosmological fine structure constant -- which contains the speed of light—may have been different than its present value in the very early Universe.

The observations supported Moffat's VSL theory—and started a race for primacy that began in 1998.

That year, five years after Moffat had published his VSL papers, João Magueijo
João Magueijo
João Magueijo is a Portuguese cosmologist and professor in Theoretical Physics at Imperial College London. He is a pioneer of the varying speed of light theory.- Career :...

 of Imperial College in London, and collaborators Andrew Albrecht of the University of California at Davis  and John D. Barrow
John D. Barrow
-External links:****** The Forum-Publications available on the Internet:************...

 of Cambridge University, published a strikingly similar idea in the more prestigious journal, Physical Review D, which had rejected Moffat's paper years earlier.

When Moffat learned of the similarities, he considered legal action to prevent Magueijo, et al. from publishing the theory. Informed of the omission, Magueijo credited Moffat with an entire chapter in Magueijo's 2002 book, Faster Than the Speed of Light: The story of a scientific speculation.

The controversy reignited, however, when during a worldwide publicity tour for Magueijo's book, the author neither credited Moffat nor corrected numerous erroneous press accounts—in such magazines as Discover Publisher's Weekly Seed Magazine and the Christian Science Monitor. In efforts to portray Magueijo as a "brash, young scientific upstart," dozens of publications attributed VSL theory entirely to Magueijo and his co-authors, leaving Moffat—in his late sixties by this time—out. Moffat expressed displeasure about the re-emergent omissions, urging reporters to check their facts, but to no avail.

Stories emerged about the book tour media omissions in March and July 2003, written by a science journalist, Michael Martin, who had earlier attributed VSL theory to Moffat in a 2001 UPI article about Webb's astronomical discoveries. Discover Magazine writer Tim Folger acknowledged the omissions in his story and apologized. In response to a reader letter from Henry van Driel of the University of Toronto Department of Physics, Folger wrote, "Professor van Driel is absolutely right—John Moffat did develop a varying speed of light theory several years before João Magueijo, and I regret not including that information in my story."

Months later, as other reports picked up on the reignited dispute, Magueijo reiterated Moffat's primacy in VSL theory. In September 2004, Discover Magazine's Tim Folger followed through on a promise he had made during the controversy to "write a story about John Moffat.".

The two physicists eventually settled their differences and became friends, publishing a joint paper in 2007 in the journal General Relativity and Gravitation.

Academic journal articles now routinely credit Moffat—and French astrophysicist Jean-Pierre Petit
Jean-Pierre Petit
Jean-Pierre Petit is a French scientist, senior researcher at National Center for Scientific Research as an astrophysicist in Marseille Observatory, now retired...

, a senior researcher at the National Center for Scientific Research  -- for primacy in the development of VSL theories. Petit published an even earlier 1988 theory involving a variable speed of light in the journal Modern Physics Letters A.

Modified Gravity Theory

Continuing Einstein's search for a unified field theory
Unified field theory
In physics, a unified field theory, occasionally referred to as a uniform field theory, 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 single field. There is no accepted unified field theory, and thus...

, Moffat proposed a Nonsymmetric Gravitational Theory
Nonsymmetric gravitational theory
In theoretical physics, the nonsymmetric gravitational theory of John Moffat is a classical theory of gravitation which tries to explain the observation of the flat rotation curves of galaxies....

 that, like Einstein's unified field, incorporated a symmetric field (gravity) and an antisymmetric field. Unlike Einstein, however, Moffat made no attempt to identify the latter with electromagnetism
Electromagnetism
Electromagnetism is one of the four fundamental interactions in nature. The other three are the strong interaction, the weak interaction and gravitation...

, instead proposing that the antisymmetric component is another manifestation of gravity. As investigation progressed, the theory evolved in a variety of ways; most notably, Moffat postulated that the antisymmetric field may be massive.

The current version of his modified gravity (MOG) theory, which grew out of this investigation, modifies Einstein's gravity with the addition of a vector field, while also promoting the constants of the theory to scalar fields. The combined effect of these fields modifies the strength of gravity at large distances when large masses are involved, successfully accounting for a range of astronomical and cosmological observations. The resulting theory describes well, without invoking dark matter
Dark matter
In astronomy and cosmology, dark matter is matter that neither emits nor scatters light or other electromagnetic radiation, and so cannot be directly detected via optical or radio astronomy...

, the rotation curves of galaxies and the mass profiles of X-ray galaxy clusters.

Non-local Quantum Field Theory

In 1990, Moffat proposed a finite, non-local quantum field theory
Quantum field theory
Quantum field theory provides a theoretical framework for constructing quantum mechanical models of systems classically parametrized by an infinite number of dynamical degrees of freedom, that is, fields and many-body systems. It is the natural and quantitative language of particle physics and...

. The theory was developed extensively by Evens, Moffat, Kleppe and Woodard in 1991. In subsequent work, Moffat proposed this theory as an alternative to the standard electroweak unification of electromagnetism
Electromagnetism
Electromagnetism is one of the four fundamental interactions in nature. The other three are the strong interaction, the weak interaction and gravitation...

 and the weak nuclear interactions. Moffat's theory is a quantum field theory
Quantum field theory
Quantum field theory provides a theoretical framework for constructing quantum mechanical models of systems classically parametrized by an infinite number of dynamical degrees of freedom, that is, fields and many-body systems. It is the natural and quantitative language of particle physics and...

 with a non-local term in the field Lagrangian
Lagrangian
The Lagrangian, L, of a dynamical system is a function that summarizes the dynamics of the system. It is named after Joseph Louis Lagrange. The concept of a Lagrangian was originally introduced in a reformulation of classical mechanics by Irish mathematician William Rowan Hamilton known as...

. Despite the non-local term the theory does not violate causality
Causality
Causality is the relationship between an event and a second event , where the second event is understood as a consequence of the first....

. The theory is finite to all orders, requiring no renormalization, and it provides a mechanism to give mass to elementary particles without having to postulate the Higgs boson
Higgs boson
The Higgs boson is a hypothetical massive elementary particle that is predicted to exist by the Standard Model of particle physics. Its existence is postulated as a means of resolving inconsistencies in the Standard Model...

. The Large Hadron Collider
Large Hadron Collider
The Large Hadron Collider is the world's largest and highest-energy particle accelerator. It is expected to address some of the most fundamental questions of physics, advancing the understanding of the deepest laws of nature....

 may confirm or falsify this theory's predictions.

See also

  • Nonsymmetric gravitational theory
    Nonsymmetric gravitational theory
    In theoretical physics, the nonsymmetric gravitational theory of John Moffat is a classical theory of gravitation which tries to explain the observation of the flat rotation curves of galaxies....

  • Variable speed of light
    Variable speed of light
    The variable speed of light concept states that the speed of light in a vacuum, usually denoted by c, may not be constant in most cases. In most situations in condensed matter physics when light is traveling through a medium, it effectively has a slower speed...

  • Scalar-tensor-vector gravity
    Scalar-tensor-vector gravity
    Scalar–tensor–vector gravity is a modified theory of gravity developed by John Moffat, a researcher at the Perimeter Institute for Theoretical Physics in Waterloo, Ontario...

  • Pioneer anomaly
    Pioneer anomaly
    The Pioneer anomaly or Pioneer effect is the observed deviation from predicted accelerations of the Pioneer 10 and Pioneer 11 spacecraft after they passed about on their trajectories out of the Solar System....


Selected articles


External links



University of Toronto press releases re Moffat:
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