Carl H. Brans
Encyclopedia
Carl Henry Brans is an American mathematical physicist best known for his research into the theoretical underpinnings of gravitation
elucidated in his most widely publicized work, the Brans–Dicke theory.
A Texan
, born in Dallas, Carl Brans spent his academic career in neighboring Louisiana
, graduating in 1957 from Loyola University New Orleans
. Having obtained his Ph.D from New Jersey
's Princeton University
in 1961, he returned to Loyola in 1960 and, in 1970, was appointed professor of physics. Since then he has held visiting professorships at Princeton University, the Intitute for Advanced Studies, and the Institute for Theoretical Physics at the University of Koeln, Germany.
Brans is well known among those engaged in the study of gravity and is noted for his development, with Robert H. Dicke
of the Brans-Dicke theory of gravitation in which the gravitational constant
varies with time, a leading competitor of Einstein's theory of general relativity
. The work of Brans and Dicke actually was closely related to earlier work of Pascal Jordan, but was developed independently. Properly this should then be called the "Jordan-Brans-Dicke," JBD, scalar-tensor theory of gravity. In this theory, based on speculations of Dirac and others, a universally coupled scalar field, in addition to the metric
, is introduced which ultimately results in a theory in which the gravitational constant
depends on the distribution of matter in the universe. A number of very accurate measurements made in the late 1970s has failed to detect this and some of the other predictions made by the Brans-Dicke theory. However, recent developments in string theory and cosmology as renewed interest in scalar field modifications of standard general relativity
.
Recently Brans began study of developments in differential topology
concerning the existence of exotic (non-standard) global differential structures and their possible applications to physics. This work includes looking at the exotic 7-sphere of Milnor as an exotic Yang-Mills bundle, and most especially the infinity of exotic differential structures on Euclidean four space as alternative models for space-time in general relativity. Much of this work has been done in collaboration with Torsten Asselmeyer-Maluga of Berlin. Together they published a book, Exotic Smoothness and Physics World Scientific Press, 2007.
Gravitation
Gravitation, or gravity, is a natural phenomenon by which physical bodies attract with a force proportional to their mass. Gravitation is most familiar as the agent that gives weight to objects with mass and causes them to fall to the ground when dropped...
elucidated in his most widely publicized work, the Brans–Dicke theory.
A Texan
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
, born in Dallas, Carl Brans spent his academic career in neighboring Louisiana
Louisiana
Louisiana is a state located in the southern region of the United States of America. Its capital is Baton Rouge and largest city is New Orleans. Louisiana is the only state in the U.S. with political subdivisions termed parishes, which are local governments equivalent to counties...
, graduating in 1957 from Loyola University New Orleans
Loyola University New Orleans
Loyola University New Orleans is a private, co-educational and Jesuit university located in New Orleans, Louisiana, United States. Originally established as Loyola College in 1904, the institution was chartered as a university in 1912. It bears the name of the Jesuit patron, Saint Ignatius of Loyola...
. Having obtained his Ph.D from New Jersey
New Jersey
New Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware...
's Princeton University
Princeton University
Princeton University is a private research university located in Princeton, New Jersey, United States. The school is one of the eight universities of the Ivy League, and is one of the nine Colonial Colleges founded before the American Revolution....
in 1961, he returned to Loyola in 1960 and, in 1970, was appointed professor of physics. Since then he has held visiting professorships at Princeton University, the Intitute for Advanced Studies, and the Institute for Theoretical Physics at the University of Koeln, Germany.
Brans is well known among those engaged in the study of gravity and is noted for his development, with Robert H. Dicke
Robert H. Dicke
Robert Henry Dicke was an American physicist who made important contributions to the fields of astrophysics, atomic physics, cosmology and gravity.-Biography:...
of the Brans-Dicke theory of gravitation in which the gravitational constant
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...
varies with time, a leading competitor of Einstein's theory 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...
. The work of Brans and Dicke actually was closely related to earlier work of Pascal Jordan, but was developed independently. Properly this should then be called the "Jordan-Brans-Dicke," JBD, scalar-tensor theory of gravity. In this theory, based on speculations of Dirac and others, a universally coupled scalar field, in addition to the metric
Metric tensor
In the mathematical field of differential geometry, a metric tensor is a type of function defined on a manifold which takes as input a pair of tangent vectors v and w and produces a real number g in a way that generalizes many of the familiar properties of the dot product of vectors in Euclidean...
, is introduced which ultimately results in a theory in which the gravitational constant
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...
depends on the distribution of matter in the universe. A number of very accurate measurements made in the late 1970s has failed to detect this and some of the other predictions made by the Brans-Dicke theory. However, recent developments in string theory and cosmology as renewed interest in scalar field modifications of standard 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...
.
Recently Brans began study of developments in differential topology
Differential topology
In mathematics, differential topology is the field dealing with differentiable functions on differentiable manifolds. It is closely related to differential geometry and together they make up the geometric theory of differentiable manifolds.- Description :...
concerning the existence of exotic (non-standard) global differential structures and their possible applications to physics. This work includes looking at the exotic 7-sphere of Milnor as an exotic Yang-Mills bundle, and most especially the infinity of exotic differential structures on Euclidean four space as alternative models for space-time in general relativity. Much of this work has been done in collaboration with Torsten Asselmeyer-Maluga of Berlin. Together they published a book, Exotic Smoothness and Physics World Scientific Press, 2007.