Flatness may refer to: *

Flatness (art) In art criticism of the 1960s and 1970s, flatness described the smoothness and absence of curvature or surface detail of a two-dimensional work of art. Views Critic Clement Greenberg believed that flatness, or two-dimensionality, was an essential ...

Flatness (cosmology) In cosmology, flatness is a property of a space without curvature. Such a space is called a "flat space" or Euclidean space. Whether the universe is “flat″ could determine its ultimate fate; whether it will expand forever, or ultimately collaps ...

Flatness (liquids) In physics, a free surface is the surface of a fluid that is subject to zero parallel shear stress, such as the interface between two homogeneous fluids. An example of two such homogeneous fluids would be a body of water (liquid) and the air in ...

Flatness (manufacturing) In manufacturing and mechanical engineering, flatness is an important geometric condition for workpieces and tools. Flatness is the condition of a surface or derived median plane having all elements in one plane. Geometric dimensioning and toler ...

, a geometrical tolerance required in certain manufacturing situations *

Flatness (systems theory) Flatness in systems theory is a system property that extends the notion of controllability from linear systems to nonlinear dynamical systems. A system that has the flatness property is called a ''flat system''. Flat systems have a (fictitious) ''f ...

, a property of nonlinear dynamic systems *

Spectral flatness Spectral flatness or tonality coefficient, also known as Wiener entropy, is a measure used in digital signal processing to characterize an audio spectrum. Spectral flatness is typically measured in decibels, and provides a way to quantify how mu ...

* Flat

intonation Intonation may refer to: *Intonation (linguistics), variation of speaking pitch that is not used to distinguish words *Intonation (music), a musician's realization of pitch accuracy, or the pitch accuracy of a musical instrument *Intonation Music ...

Flat module In algebra, flat modules include free modules, projective modules, and, over a principal ideal domain, torsion-free modules. Formally, a module (mathematics), module ''M'' over a ring (mathematics), ring ''R'' is ''flat'' if taking the tensor prod ...

in abstract algebra *

Flat morphism In mathematics, in particular in algebraic geometry, a flat morphism ''f'' from a scheme (mathematics), scheme ''X'' to a scheme ''Y'' is a morphism such that the induced map on every Stalk (sheaf), stalk is a flat map of rings, i.e., :f_P\colon \ ...

in algebraic geometry

See also