Knot (mathematics)In mathematics, a knot is an embedding of the circle S^1 into three-dimensional Euclidean space, R3 (also known as E3). Often two knots are considered equivalent if they are ambient isotopic, that is, if there exists a continuous deformation of R3 which takes one knot to the other. A crucial difference between the standard mathematical and conventional notions of a knot is that mathematical knots are closed — there are no ends to tie or untie on a mathematical knot.
Medieval artThe medieval art of the Western world covers a vast scope of time and place, with over 1000 years of art in Europe, and at certain periods in Western Asia and Northern Africa. It includes major art movements and periods, national and regional art, genres, revivals, the artists' crafts, and the artists themselves. Art historians attempt to classify medieval art into major periods and styles, often with some difficulty.
Art historyArt history is the study of aesthetic objects and visual expression in historical and stylistic context. Traditionally, the discipline of art history emphasized painting, drawing, sculpture, architecture, ceramics and decorative arts; yet today, art history examines broader aspects of visual culture, including the various visual and conceptual outcomes related to an ever-evolving definition of art. Art history encompasses the study of objects created by different cultures around the world and throughout history that convey meaning, importance or serve usefulness primarily through visual representations.
Representation theoryRepresentation theory is a branch of mathematics that studies abstract algebraic structures by representing their elements as linear transformations of vector spaces, and studies modules over these abstract algebraic structures. In essence, a representation makes an abstract algebraic object more concrete by describing its elements by matrices and their algebraic operations (for example, matrix addition, matrix multiplication).
Irreducible representationIn mathematics, specifically in the representation theory of groups and algebras, an irreducible representation or irrep of an algebraic structure is a nonzero representation that has no proper nontrivial subrepresentation , with closed under the action of . Every finite-dimensional unitary representation on a Hilbert space is the direct sum of irreducible representations. Irreducible representations are always indecomposable (i.e. cannot be decomposed further into a direct sum of representations), but the converse may not hold, e.
Group representationIn the mathematical field of representation theory, group representations describe abstract groups in terms of bijective linear transformations of a vector space to itself (i.e. vector space automorphisms); in particular, they can be used to represent group elements as invertible matrices so that the group operation can be represented by matrix multiplication. In chemistry, a group representation can relate mathematical group elements to symmetric rotations and reflections of molecules.
Algebra representationIn abstract algebra, a representation of an associative algebra is a module for that algebra. Here an associative algebra is a (not necessarily unital) ring. If the algebra is not unital, it may be made so in a standard way (see the adjoint functors page); there is no essential difference between modules for the resulting unital ring, in which the identity acts by the identity mapping, and representations of the algebra.
Regular representationIn mathematics, and in particular the theory of group representations, the regular representation of a group G is the linear representation afforded by the group action of G on itself by translation. One distinguishes the left regular representation λ given by left translation and the right regular representation ρ given by the inverse of right translation. Representation theory of finite groups#Left- and right-regular representation For a finite group G, the left regular representation λ (over a field K) is a linear representation on the K-vector space V freely generated by the elements of G, i.
Public artPublic art is art in any media whose form, function and meaning are created for the general public through a public process. It is a specific art genre with its own professional and critical discourse. Public art is visually and physically accessible to the public; it is installed in public space in both outdoor and indoor settings. Public art seeks to embody public or universal concepts rather than commercial, partisan, or personal concepts or interests.
