Superstring theory
'Superstring theory' is a shorthand for supersymmetric string theory because unlike bosonic string theory, it is the version of string theory that accounts for both fermions and bosons and incorporates supersymmetry to model gravity. Since the second superstring revolution, the five superstring theories are regarded as different limits of a single theory tentatively called M-theory. Background[edit] The deepest problem in theoretical physics is harmonizing the theory of general relativity, which describes gravitation and applies to large-scale structures (stars, galaxies, super clusters), with quantum mechanics, which describes the other three fundamental forces acting on the atomic scale. The development of a quantum field theory of a force invariably results in infinite possibilities. History[edit] Lack of experimental evidence[edit] Superstring theory is based on supersymmetry. Extra dimensions[edit] Superstring theory is not the first theory to propose extra spatial dimensions.
Edward Witten
Edward Witten (born August 26, 1951) is an American theoretical physicist and professor of mathematical physics at the Institute for Advanced Study in Princeton, New Jersey. Witten is a researcher in string theory, quantum gravity, supersymmetric quantum field theories, and other areas of mathematical physics. In addition to his contributions to physics, Witten's work has significantly impacted pure mathematics.[4] In 1990, he became the first physicist to be awarded a Fields Medal by the International Mathematical Union, awarded for his 1981 proof of the positive energy theorem in general relativity.[5] Early life and education[edit] Witten was born in Baltimore, Maryland, to a Jewish family.[6] He is the son of Lorraine (Wollach) Witten and Louis Witten, a theoretical physicist specializing in gravitation and general relativity.[7] Research[edit] Fields medal work[edit] In a written address to the ICM, Michael Atiyah said of Witten,[4] M-theory[edit] Other work[edit] Awards and honors[edit]
Field
From Wikipedia, the free encyclopedia Jump to navigationJump to search Field may refer to: Expanses of open ground[edit] People[edit] Places[edit] Science[edit] Mathematics[edit] Physics[edit] Engineering and computing[edit] Sociology and politics[edit] Businesses[edit] Field Enterprises, a defunct private holding company Field Communications, a division of Field EnterprisesField Records, a record label Technical uses[edit] Other[edit] See also[edit]
Matrix (mathematics)
Array of numbers For example, is a matrix with two rows and three columns. This is often referred to as a "two by three matrix", a " matrix", or a matrix of dimension Square matrices, matrices with the same number of rows and columns, play a major role in matrix theory. Matrix theory is the branch of mathematics that focuses on the study of matrices. Definition[edit] The numbers, symbols, or expressions in the matrix are called its entries or its elements. Size[edit] The size of a matrix is defined by the number of rows and columns it contains. Notation[edit] The specifics of symbolic matrix notation vary widely, with some prevailing trends. matrix represented as This may be abbreviated by writing only a single generic term, possibly along with indices, as in or in the case that The entry in the i-th row and j-th column of a matrix A is sometimes referred to as the i,j or (i, j) entry of the matrix, and commonly denoted by ai,j or aij. is used in place of Basic operations[edit] Addition Subtraction
string theory | Explanation & Definition
String theory, in particle physics, a theory that attempts to merge quantum mechanics with Albert Einstein’s general theory of relativity. The name string theory comes from the modeling of subatomic particles as tiny one-dimensional “stringlike” entities rather than the more conventional approach in which they are modeled as zero-dimensional point particles. The theory envisions that a string undergoing a particular mode of vibration corresponds to a particle with definite properties such as mass and charge. Read More on This Topic cosmology: Superunification and the Planck era Why should a net baryon fraction initially of zero be more appealing aesthetically than 10−9? Relativity and quantum mechanics In 1905 Einstein unified space and time (see space-time) with his special theory of relativity, showing that motion through space affects the passage of time. Predictions and theoretical difficulties Facts Matter. The announcement was universally ignored. Dimensions and vibrations
String theory
Theoretical framework in physics String theory is a broad and varied subject that attempts to address a number of deep questions of fundamental physics. String theory has contributed a number of advances to mathematical physics, which have been applied to a variety of problems in black hole physics, early universe cosmology, nuclear physics, and condensed matter physics, and it has stimulated a number of major developments in pure mathematics. Because string theory potentially provides a unified description of gravity and particle physics, it is a candidate for a theory of everything, a self-contained mathematical model that describes all fundamental forces and forms of matter. Despite much work on these problems, it is not known to what extent string theory describes the real world or how much freedom the theory allows in the choice of its details. One of the challenges of string theory is that the full theory does not have a satisfactory definition in all circumstances. Fundamentals
Theory of relativity
Two interrelated physics theories by Albert Einstein The theory of relativity usually encompasses two interrelated physics theories by Albert Einstein: special relativity and general relativity, proposed and published in 1905 and 1915, respectively.[1] Special relativity applies to all physical phenomena in the absence of gravity. General relativity explains the law of gravitation and its relation to the forces of nature.[2] It applies to the cosmological and astrophysical realm, including astronomy.[3] The theory transformed theoretical physics and astronomy during the 20th century, superseding a 200-year-old theory of mechanics created primarily by Isaac Newton.[3][4][5] It introduced concepts including 4-dimensional spacetime as a unified entity of space and time, relativity of simultaneity, kinematic and gravitational time dilation, and length contraction. Development and acceptance Special relativity Special relativity is a theory of the structure of spacetime. General relativity
General relativity
Theory of gravitation as curved spacetime General relativity, also known as the general theory of relativity and Einstein's theory of gravity, is the geometric theory of gravitation published by Albert Einstein in 1915 and is the current description of gravitation in modern physics. General relativity generalises special relativity and refines Newton's law of universal gravitation, providing a unified description of gravity as a geometric property of space and time or four-dimensional spacetime. In particular, the curvature of spacetime is directly related to the energy and momentum of whatever matter and radiation are present. The relation is specified by the Einstein field equations, a system of second order partial differential equations. Newton's law of universal gravitation, which describes classical gravity, can be seen as a prediction of general relativity for the almost flat spacetime geometry around stationary mass distributions. History[edit] Geometry of Newtonian gravity[edit]
