Differential algebraIn mathematics, differential algebra is, broadly speaking, the area of mathematics consisting in the study of differential equations and differential operators as algebraic objects in view of deriving properties of differential equations and operators without computing the solutions, similarly as polynomial algebras are used for the study of algebraic varieties, which are solution sets of systems of polynomial equations. Weyl algebras and Lie algebras may be considered as belonging to differential algebra.
British EnglishBritish English (BrE, en-GB, or BE) is, according to Oxford Dictionaries, "English as used in Great Britain, as distinct from that used elsewhere". More narrowly, it can refer specifically to the English language in England, or, more broadly, to the collective dialects of English throughout the British Isles taken as a single umbrella variety, for instance additionally incorporating Scottish English, Welsh English, and Northern Irish English.
Differential equationIn mathematics, a differential equation is an equation that relates one or more unknown functions and their derivatives. In applications, the functions generally represent physical quantities, the derivatives represent their rates of change, and the differential equation defines a relationship between the two. Such relations are common; therefore, differential equations play a prominent role in many disciplines including engineering, physics, economics, and biology.
GradientIn vector calculus, the gradient of a scalar-valued differentiable function of several variables is the vector field (or vector-valued function) whose value at a point is the "direction and rate of fastest increase". If the gradient of a function is non-zero at a point , the direction of the gradient is the direction in which the function increases most quickly from , and the magnitude of the gradient is the rate of increase in that direction, the greatest absolute directional derivative.
Middle EnglishMiddle English (abbreviated to ME) is a form of the English language that was spoken after the Norman Conquest of 1066, until the late 15th century. The English language underwent distinct variations and developments following the Old English period. Scholarly opinion varies, but the Oxford English Dictionary specifies the period when Middle English was spoken as being from 1150 to 1500. This stage of the development of the English language roughly followed the High to the Late Middle Ages.
English languageEnglish is a West Germanic language in the Indo-European language family. It originated in early medieval England and, today, is the most spoken language in the world and the third most spoken native language, after Mandarin Chinese and Spanish. English is the most widely learned second language and is either the official language or one of the official languages in 59 sovereign states. There are more people who have learned English as a second language than there are native speakers.
International EnglishInternational English is the concept of using the English language as a global means of communication similar to an international auxiliary language, and often refers to the movement towards an international standard for the language. Related and sometimes synonymous terms include: Global English, World English, Common English, Continental English, General English, and Engas (English as associate language). Sometimes, these terms refer to the actuality of the situation, where English is spoken and used in numerous dialects around the world.
Hiberno-EnglishHiberno-English (haɪ'bɜːrnoʊ_-,_hɪ-; from Latin Hibernia: "Ireland") or Irish English (IrE), also formerly Anglo-Irish, is the set of English dialects native to the island of Ireland (including both the Republic of Ireland and Northern Ireland). In the Republic of Ireland, English is one of two official languages, along with the Irish language, and is the country's de facto working language. Irish English's writing standards, such as its spelling, align with British English.
Triple productIn geometry and algebra, the triple product is a product of three 3-dimensional vectors, usually Euclidean vectors. The name "triple product" is used for two different products, the scalar-valued scalar triple product and, less often, the vector-valued vector triple product. The scalar triple product (also called the mixed product, box product, or triple scalar product) is defined as the dot product of one of the vectors with the cross product of the other two.
American EnglishAmerican English, sometimes called United States English or U.S. English, is the set of varieties of the English language native to the United States. English is the most widely spoken language in the United States and in most circumstances is the de facto common language used in government, education and commerce. Since the late 20th century, American English has become the most influential form of English worldwide.
Tensor productIn mathematics, the tensor product of two vector spaces V and W (over the same field) is a vector space to which is associated a bilinear map that maps a pair to an element of denoted An element of the form is called the tensor product of v and w. An element of is a tensor, and the tensor product of two vectors is sometimes called an elementary tensor or a decomposable tensor. The elementary tensors span in the sense that every element of is a sum of elementary tensors.
Elliptic operatorIn the theory of partial differential equations, elliptic operators are differential operators that generalize the Laplace operator. They are defined by the condition that the coefficients of the highest-order derivatives be positive, which implies the key property that the principal symbol is invertible, or equivalently that there are no real characteristic directions. Elliptic operators are typical of potential theory, and they appear frequently in electrostatics and continuum mechanics.