In algebraic geometry, the moduli stack of formal group laws is a
stack
Stack may refer to:
Places
* Stack Island, an island game reserve in Bass Strait, south-eastern Australia, in Tasmania’s Hunter Island Group
* Blue Stack Mountains, in Co. Donegal, Ireland
People
* Stack (surname) (including a list of people ...
classifying
formal group laws and isomorphisms between them. It is denoted by
. It is a "geometric “object" that underlies the
chromatic
Diatonic and chromatic are terms in music theory that are most often used to characterize scales, and are also applied to musical instruments, intervals, chords, notes, musical styles, and kinds of harmony. They are very often used as a pair, ...
approach to the
stable homotopy theory
In mathematics, stable homotopy theory is the part of homotopy theory (and thus algebraic topology) concerned with all structure and phenomena that remain after sufficiently many applications of the suspension functor. A founding result was the F ...
, a branch of
algebraic topology.
Currently, it is not known whether
is a
derived stack In algebraic geometry, a derived stack is, roughly, a stack together with a sheaf of commutative ring spectra. It generalizes a derived scheme. Derived stacks are the "spaces" studied in derived algebraic geometry Derived algebraic geometry is a br ...
or not. Hence, it is typical to work with stratifications. Let
be given so that
consists of formal group laws over ''R'' of height exactly ''n''. They form a stratification of the moduli stack
.
is
faithfully flat. In fact,
is of the form
where
is a
profinite group In mathematics, a profinite group is a topological group that is in a certain sense assembled from a system of finite groups.
The idea of using a profinite group is to provide a "uniform", or "synoptic", view of an entire system of finite groups. ...
called the Morava stabilizer group. The
Lubin–Tate theory describes how the strata
fit together.
References
*
*
Further reading
*
Topology
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