| [Edit]
Density and dense usually refer to a measure of how much of some entity is "in" a fixed amount of other space. Types of density include:
In physics:
Relative density (specific gravity), a measure of density in comparison to the density of something else, often used with respect to liquids
Energy density, potential energy per unit volume or mass, depending on context
In mathematics:
Probability density function, a function which maps probabilities across the real line and whose integral is 1 (as in, something must always happen).
Density in graph theory, the fraction of possible edges that exist in a graph.
In order theory, a subset B of a partially ordered set A is dense in A if for any x < y in A, there is some z in B such that x < z < y. In case the order is a linear order, then B is dense in A in the present sense if and only if B is a dense set with respect to the order topology on A.
In forcing (mathematics), a subset D of a forcing notion (P, ≤ ) is called dense in P if for any p in P there is d in D with d≤p. (Note: since a forcing notion is also a partial order, this usage of the word "dense" conflicts with the definition given above. However, the above notion of "density" is practically never used when talking about forcing notions, so any ambiguities are usually easily resolved from the context.)
In other scientific fields:
Density can also refer to:
|
|
