Canonical

The term canonical may refer to:

Mathematics

• Canonical coordinates, sets of coordinates which can be used to describe a physical system at any given point in time
• Canonical form, a natural unique representation of an object, or a preferred notation for some object
• Canonical homomorphism, canonical isomorphism: an homomorphism that is uniquely defined by its main property
• Canonical polyhedron, in geometry a polyhedron whose edges are all tangent to a common sphere, whose center is the average of its vertices (midsphere)
• Canonical representative, in set theory a standard member of each element of a set partition

Differential geometry

• Canonical one-form, a special 1-form defined on the cotangent bundle T*M of a manifold M
• Canonical symplectic form, the exterior derivative of this form
• Canonical vector field, the corresponding special vector field defined on the tangent bundle TM of a manifold M

Physics

• Canonical ensemble, in statistical mechanics, is a statistical ensemble representing a probability distribution of microscopic states of the system
  • Grand canonical ensemble, a probability distribution of microscopic states for an open system, which is being maintained in thermodynamic equilibrium
  • Microcanonical ensemble, a theoretical tool used to analyze an isolated thermodynamic system
• Canonical quantum gravity, an attempt to quantize the canonical formulation of general relativity
• Canonical stress–energy tensor, a conserved current associated with translations through space and time
• Canonical theory, a unified molecular theory of physics, chemistry, and biology
• Canonical variable, a conjugate variable in theoretical physics
• Canonical transformation, in Hamiltonian mechanics

Computer science

• Canonical form, data that has been canonicalized into a completely unique representation, from a previous form that had more than one possible representation
• Canonical Huffman code, a particular type of Huffman code with unique properties which allow it to be described in a very compact manner
• Canonical link element, an HTML element that helps webmasters prevent duplicate content issues by specifying the "canonical" or "preferred" version
• Canonical (company), a UK software company that develops, markets and supports related services for Ubuntu and related projects
• Canonical Model, a design pattern used to communicate between different data formats
• Canonical name record (CNAME record), a type of Domain Name System record
• Canonical S-expressions, a binary encoding form of a subset of general S-expression
• Canonical XML, a normal form of XML, intended to allow relatively simple comparison of pairs of XML documents
• MAC address (formerly canonical number), a unique identifier assigned to network interfaces for communications on the physical network segment

Religion

• Canon law (Catholic Church)
• Canonical Coronation, an institutional act of the pope to legally crown images venerated by the faithful through a papal bull
• Canonical hours, the divisions of the day in terms of periods of fixed prayer at regular intervals.
• Biblical canon
  • Canonical gospel, the four gospels accepted as part of the New Testament
  • Canonical criticism, a way of interpreting the Bible that focuses on the text of the biblical canon itself as a finished product
• The scriptures of the Pāli Canon of Theravāda Buddhism (these include the Sutta Pitaka, the Vinaya Pitaka, and the Abhidhamma Pitaka)

See also

• Archetype
• Canon (disambiguation)
• Canonicalization, a process for converting data to canonical form
• Canonization, the act of a pope's declaring a deceased person a saint