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qform

qform, or a q-form, is a concept from differential geometry referring to an exterior differential form of degree q on a smooth manifold. For q = 0, a q-form is a smooth function; for q = 1, it is a covector field. More generally, q-forms are antisymmetric multilinear forms on the tangent spaces, and the collection of all q-forms on a manifold M is denoted Λ^q(T* M).

q-forms form a graded algebra under addition and the wedge product: the wedge of a p-form and

In practice, 0-forms are functions, 1-forms are linear combinations of differentials such as dx, dy, and 2-forms

In physics and engineering, q-forms are used to model fields and fluxes; for example, the electromagnetic field

a
q-form
is
a
(p+q)-form.
The
exterior
derivative
d
maps
Λ^q
to
Λ^{q+1}
and
satisfies
d^2
=
0,
allowing
the
definition
of
closed
forms
(dω
=
0)
and
exact
forms
(ω
=
dη).
These
structures
underpin
de
Rham
cohomology,
which
classifies
global
topological
properties
of
manifolds
via
the
quotient
of
closed
forms
by
exact
forms.
can
be
written
as
combinations
like
f
dx
∧
dy.
The
integral
of
a
q-form
over
an
oriented
q-dimensional
submanifold
generalizes
line
and
surface
integrals,
and
Stokes’
theorem
provides
a
unifying
framework:
the
integral
of
dω
over
a
region
equals
the
integral
of
ω
over
the
region’s
boundary.
is
described
by
a
2-form
on
spacetime.
The
term
qform
can
also
appear
as
a
stylized
or
project-specific
name
in
software
or
literature,
but
its
precise
meaning
is
determined
by
context.