Continuous monoid action #
In this file we define class has_continuous_smul. We say has_continuous_smul M X if M acts on
X and the map (c, x) ↦ c • x is continuous on M × X. We reuse this class for topological
(semi)modules, vector spaces and algebras.
Main definitions #
has_continuous_smul M X: typeclass saying that the map(c, x) ↦ c • xis continuous onM × X;homeomorph.smul_of_ne_zero: if a group with zeroG₀(e.g., a field) acts onXandc : G₀is a nonzero element ofG₀, then scalar multiplication bycis a homeomorphism ofX;homeomorph.smul: scalar multiplication by an element of a groupGacting onXis a homeomorphism ofX.units.has_continuous_smul: scalar multiplication byMˣis continuous when scalar multiplication byMis continuous. This allowshomeomorph.smulto be used with on monoids withG = Mˣ.
Main results #
Besides homeomorphisms mentioned above, in this file we provide lemmas like continuous.smul
or filter.tendsto.smul that provide dot-syntax access to continuous_smul.
- continuous_smul : continuous (λ (p : M × X), p.fst • p.snd)
Class has_continuous_smul M X says that the scalar multiplication (•) : M → X → X
is continuous in both arguments. We use the same class for all kinds of multiplicative actions,
including (semi)modules and algebras.
Instances
- module_filter_basis.has_continuous_smul
- has_continuous_smul.op
- units.has_continuous_smul
- prod.has_continuous_smul
- pi.has_continuous_smul
- has_continuous_mul.has_continuous_smul
- add_monoid.has_continuous_smul_nat
- add_group.has_continuous_smul_int
- quotient_group.has_continuous_smul
- submodule.has_continuous_smul
- submodule.topological_closure_has_continuous_smul
- nnreal.real.has_continuous_smul
- continuous_vadd : continuous (λ (p : M × X), p.fst +ᵥ p.snd)
Class has_continuous_vadd M X says that the additive action (+ᵥ) : M → X → X
is continuous in both arguments. We use the same class for all kinds of additive actions,
including (semi)modules and algebras.
If a scalar is central, then its right action is continuous when its left action is.