Hyperbolic geometryIn mathematics, hyperbolic geometry (also called Lobachevskian geometry or Bolyai–Lobachevskian geometry) is a non-Euclidean geometry. The parallel postulate of Euclidean geometry is replaced with: For any given line R and point P not on R, in the plane containing both line R and point P there are at least two distinct lines through P that do not intersect R. (Compare the above with Playfair's axiom, the modern version of Euclid's parallel postulate.) The hyperbolic plane is a plane where every point is a saddle point.
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.
Classical antiquityClassical antiquity, also known as the classical era, classical period, classical age, or simply antiquity, is the period of cultural history between the 8th century BC and the 8th century AD centered on the Mediterranean Sea, comprising the interlocking civilizations of ancient Greece and ancient Rome known as the Greco-Roman world. It is the period in which both Greek and Roman societies flourished and wielded huge influence throughout much of Europe, North Africa, and West Asia.
Lie algebra representationIn the mathematical field of representation theory, a Lie algebra representation or representation of a Lie algebra is a way of writing a Lie algebra as a set of matrices (or endomorphisms of a vector space) in such a way that the Lie bracket is given by the commutator. In the language of physics, one looks for a vector space together with a collection of operators on satisfying some fixed set of commutation relations, such as the relations satisfied by the angular momentum operators.
HistoryHistory (derived ) is the systematic study and documentation of the human past. The period of events before the invention of writing systems is considered prehistory. "History" is an umbrella term comprising past events as well as the memory, discovery, collection, organization, presentation, and interpretation of these events. Historians seek knowledge of the past using historical sources such as written documents, oral accounts, art and material artifacts, and ecological markers.
Projective harmonic conjugateIn projective geometry, the harmonic conjugate point of a point on the real projective line with respect to two other points is defined by the following construction: Given three collinear points A, B, C, let L be a point not lying on their join and let any line through C meet LA, LB at M, N respectively. If AN and BM meet at K, and LK meets AB at D, then D is called the harmonic conjugate of C with respect to A and B. The point D does not depend on what point L is taken initially, nor upon what line through C is used to find M and N.
Renaissance architectureRenaissance architecture is the European architecture of the period between the early 15th and early 16th centuries in different regions, demonstrating a conscious revival and development of certain elements of ancient Greek and Roman thought and material culture. Stylistically, Renaissance architecture followed Gothic architecture and was succeeded by Baroque architecture. Developed first in Florence, with Filippo Brunelleschi as one of its innovators, the Renaissance style quickly spread to other Italian cities.
ArchitectureArchitecture is the art and technique of designing and building, as distinguished from the skills associated with construction. It is both the process and the product of sketching, conceiving, planning, designing, and constructing buildings or other structures. The term comes ; ; . Architectural works, in the material form of buildings, are often perceived as cultural symbols and as works of art. Historical civilizations are often identified with their surviving architectural achievements.
ArtArt is a diverse range of human activity, and resulting product, that involves creative or imaginative talent expressive of technical proficiency, beauty, emotional power, or conceptual ideas. There is no generally agreed definition of what constitutes art, and its interpretation has varied greatly throughout history and across cultures. In the Western tradition, the three classical branches of visual art are painting, sculpture, and architecture.
HistoriographyHistoriography is the study of the methods of historians in developing history as an academic discipline, and by extension is any body of historical work on a particular subject. The historiography of a specific topic covers how historians have studied that topic by using particular sources, techniques, and theoretical approaches. Scholars discuss historiography by topic—such as the historiography of the United Kingdom, that of WWII, the pre-Columbian Americas, early Islam, and China—and different approaches and genres, such as political history and social history.
Florence CathedralFlorence Cathedral (Duomo di Firenze), formally the Cathedral of Saint Mary of the Flower (Cattedrale di Santa Maria del Fiore katteˈdraːle di ˈsanta maˈriːa del ˈfjoːre), is the cathedral of Florence, Italy. It was begun in 1296 in the Gothic style to a design of Arnolfo di Cambio and was structurally completed by 1436, with the dome engineered by Filippo Brunelleschi. The exterior of the basilica is faced with polychrome marble panels in various shades of green and pink, bordered by white, and has an elaborate 19th-century Gothic Revival façade by Emilio De Fabris.
Renaissance artRenaissance art (1350 – 1620 AD) is the painting, sculpture, and decorative arts of the period of European history known as the Renaissance, which emerged as a distinct style in Italy in about AD 1400, in parallel with developments which occurred in philosophy, literature, music, science, and technology. Renaissance art took as its foundation the art of Classical antiquity, perceived as the noblest of ancient traditions, but transformed that tradition by absorbing recent developments in the art of Northern Europe and by applying contemporary scientific knowledge.
