Vertex

from Wikipedia, the free encyclopedia

Vertex (plural: Vertices ) comes from the Latin vertere : to turn, to turn, and means first of all turning point, vertex; but also a general point, knot - a place where directions meet.
Generally also referred to as point , vector , n-tuple or (technical) data set .

Geometry, graph theory

In geometry, a vertex is a corner of a polygon .
In graph theory , it is a synonym for a node .

Computer graphics

In 3D computer graphics , a vertex is a corner , focal point , center or apex of a primitive and, in addition to position information in the form of a 3D vector, usually contains other information such as a color , transparency or a second position information that can be used for other purposes (e.g. texture coordinates ). Most of the data of the vertices are interpolated by the shading using the associated primitives.

Polygonal modeling : Here the vertex is a basic building block: two vertices together form the end points of a line , three vertices define a triangle , etc.

The conversion of the coordinates of the vertices, for example for projection by the virtual camera onto the screen, is mostly done using homogeneous coordinates .

Nuclear and Particle Physics

In nuclear and particle physics , the vertex denotes the origin of particle tracks. In addition to the main vertex, the collision point of an accelerated pair of particles, there may be secondary vertices, for example of decaying daughter particles. The vertex function Γ also plays a central role , for example in quantum field theories , e.g. B. to use the LSZ reduction formula to calculate the S-matrix elements of the scattering amplitude from the time-ordered correlation functions of a quantum field theory. The LSZ reduction formula states that the scattering amplitudes are given by the corresponding vertex functions.

astronomy

In astronomy , the term vertex is understood as the common target point of the movement of a group of stars .

Neuroanatomy

The term is also used in the field of neuroanatomy . In vertebrate neuroanatomy, "vertex" means the top of the skull . This usually consists of four bones : the two parietal bones , the frontal and occipital bones , all of which are connected to one another via the sagittal suture , the lambdoid suture and the coronal suture .

optics

In optics , the vertex is the point of intersection of an optical element with the optical axis . For a spherical lens, this is usually the pole of the lens .

Individual evidence

  1. Duden | Vertex | Spelling, meaning, definition, origin. Retrieved January 4, 2020 .
  2. H. Lehmann, K. Symanzik, W. Zimmermann: On the vertex function in quantized field theories . In: Il Nuovo Cimento (1955-1965) . tape 2 , no. 3 , September 1, 1955, ISSN  1827-6121 , p. 425-432 , doi : 10.1007 / BF02826501 .
  3. Duden | Vertex | Spelling, meaning, definition, origin. Retrieved January 4, 2020 .