In linear algebra, a one-form on a vector space is the same as a linear functional on the space. The usage of one-form in this context usually distinguishes the one-forms from higher-degree multilinear functionals on the space. For details, see linear functional.
In differential geometry, a one-form on a differentiable manifold is a smooth section of the cotangent bundle. Equivalently, a one-form on a manifold



M


{\displaystyle M}
is a smooth mapping of the total space of the tangent bundle of



M


{\displaystyle M}
to




R



{\displaystyle \mathbb {R} }
whose restriction to each fibre is a linear functional on the tangent space. Symbolically,

where




α

x




{\displaystyle \alpha _{x}}
is linear.
Often one-forms are described locally, particularly in local coordinates. In a local coordinate system, a one-form is a linear combination of the differentials of the coordinates:

where the




f

i




{\displaystyle f_{i}}
are smooth functions. From this perspective, a one-form has a covariant transformation law on passing from one coordinate system to another. Thus a one-form is an order 1 covariant tensor field.

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  1. Bandook

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  2. pacmanwa

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  3. KEMOSABEJR1

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  5. 1775usmc

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  6. papersoldier

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  7. DownRangeDuck

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  12. O

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  17. C

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