Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
The Zariski locale of a commutative ring (#619)
This pull request introduces the following concepts to agda-unimath: - Commutative algebra: - Full ideals of commutative rings - Intersections of ideals in commutative rings - Intersections of radical ideals in commutative rings. In this file we also show that the intersection of `I` and `J` is the radical of the product `IJ`. - Joins of ideals in commutative rings - Joins of radical ideals in commutative rings - The large poset of ideals in a commutative ring - The large poset of radical ideals in a commutative ring - Products of ideals in commutative rings - Products of radical ideals in commutative rings - Products of subsets of commutative rings - Radical ideals generated by subsets of commutative rings - The Zariski locale of a commutative ring - Group theory - Generating sets of groups - Intersections of subgroups of abelian groups - Intersections of subgroups of groups - Subsets of abelian groups - Subsets of groups - Order theory - Closure operators on large locales - Closure operators on large posets - Reflective Galois connections - Similarity of elements of large posets - Similarity of elements of large preorders - Ring theory - Full ideals of rings - Intersections of ideals of a ring - Intersections of ideals of a semiring - Joins of ideals of rings - Joins of left ideals of rings - Joins of right ideals of rings - Left ideals generated by subsets of a ring - Left ideals of a ring - The poset of ideals of a ring - The poset of left ideals of a ring - The poset of right ideals of a ring - Products of ideals of a ring - Products of left ideals of a ring - Products of right ideals of a ring - Right ideals generated by subsets of a ring - Right ideals of a ring --------- Co-authored-by: Masa Zaucer <masa.zaucer@student.fmf.uni-lj.si> Co-authored-by: Fredrik Bakke <fredrbak@gmail.com>
- Loading branch information
1 parent
f505b91
commit c251a28
Showing
103 changed files
with
10,127 additions
and
793 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
237 changes: 237 additions & 0 deletions
237
src/commutative-algebra/full-ideals-commutative-rings.lagda.md
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,237 @@ | ||
# Full ideals of commutative rings | ||
|
||
```agda | ||
module commutative-algebra.full-ideals-commutative-rings where | ||
``` | ||
|
||
<details><summary>Imports</summary> | ||
|
||
```agda | ||
open import commutative-algebra.commutative-rings | ||
open import commutative-algebra.ideals-commutative-rings | ||
open import commutative-algebra.poset-of-ideals-commutative-rings | ||
open import commutative-algebra.poset-of-radical-ideals-commutative-rings | ||
open import commutative-algebra.radical-ideals-commutative-rings | ||
open import commutative-algebra.subsets-commutative-rings | ||
|
||
open import foundation.dependent-pair-types | ||
open import foundation.full-subtypes | ||
open import foundation.propositions | ||
open import foundation.subtypes | ||
open import foundation.unit-type | ||
open import foundation.universe-levels | ||
|
||
open import order-theory.top-elements-large-posets | ||
|
||
open import ring-theory.full-ideals-rings | ||
``` | ||
|
||
</details> | ||
|
||
## Idea | ||
|
||
A **full ideal** in a | ||
[commutative ring](commutative-algebra.commutative-rings.md) `A` is an | ||
[ideal](commutative-algebra.ideals-commutative-rings.md) that contains every | ||
element of `A`. | ||
|
||
## Definitions | ||
|
||
### The predicate of being a full ideal | ||
|
||
```agda | ||
module _ | ||
{l1 l2 : Level} (A : Commutative-Ring l1) (I : ideal-Commutative-Ring l2 A) | ||
where | ||
|
||
is-full-ideal-Commutative-Ring-Prop : Prop (l1 ⊔ l2) | ||
is-full-ideal-Commutative-Ring-Prop = | ||
is-full-ideal-Ring-Prop (ring-Commutative-Ring A) I | ||
|
||
is-full-ideal-Commutative-Ring : UU (l1 ⊔ l2) | ||
is-full-ideal-Commutative-Ring = | ||
is-full-ideal-Ring (ring-Commutative-Ring A) I | ||
|
||
is-prop-is-full-ideal-Commutative-Ring : | ||
is-prop is-full-ideal-Commutative-Ring | ||
is-prop-is-full-ideal-Commutative-Ring = | ||
is-prop-is-full-ideal-Ring (ring-Commutative-Ring A) I | ||
``` | ||
|
||
### The (standard) full ideal | ||
|
||
```agda | ||
module _ | ||
{l1 : Level} (A : Commutative-Ring l1) | ||
where | ||
|
||
subset-full-ideal-Commutative-Ring : subset-Commutative-Ring lzero A | ||
subset-full-ideal-Commutative-Ring = | ||
subset-full-ideal-Ring (ring-Commutative-Ring A) | ||
|
||
is-in-full-ideal-Commutative-Ring : type-Commutative-Ring A → UU lzero | ||
is-in-full-ideal-Commutative-Ring = | ||
is-in-full-ideal-Ring (ring-Commutative-Ring A) | ||
|
||
contains-zero-full-ideal-Commutative-Ring : | ||
contains-zero-subset-Commutative-Ring A subset-full-ideal-Commutative-Ring | ||
contains-zero-full-ideal-Commutative-Ring = | ||
contains-zero-full-ideal-Ring (ring-Commutative-Ring A) | ||
|
||
is-closed-under-addition-full-ideal-Commutative-Ring : | ||
is-closed-under-addition-subset-Commutative-Ring A | ||
subset-full-ideal-Commutative-Ring | ||
is-closed-under-addition-full-ideal-Commutative-Ring = | ||
is-closed-under-addition-full-ideal-Ring (ring-Commutative-Ring A) | ||
|
||
is-closed-under-negatives-full-ideal-Commutative-Ring : | ||
is-closed-under-negatives-subset-Commutative-Ring A | ||
subset-full-ideal-Commutative-Ring | ||
is-closed-under-negatives-full-ideal-Commutative-Ring = | ||
is-closed-under-negatives-full-ideal-Ring (ring-Commutative-Ring A) | ||
|
||
is-additive-subgroup-full-ideal-Commutative-Ring : | ||
is-additive-subgroup-subset-Commutative-Ring A | ||
subset-full-ideal-Commutative-Ring | ||
is-additive-subgroup-full-ideal-Commutative-Ring = | ||
is-additive-subgroup-full-ideal-Ring (ring-Commutative-Ring A) | ||
|
||
is-closed-under-left-multiplication-full-ideal-Commutative-Ring : | ||
is-closed-under-left-multiplication-subset-Commutative-Ring A | ||
subset-full-ideal-Commutative-Ring | ||
is-closed-under-left-multiplication-full-ideal-Commutative-Ring = | ||
is-closed-under-left-multiplication-full-ideal-Ring | ||
( ring-Commutative-Ring A) | ||
|
||
is-closed-under-right-multiplication-full-ideal-Commutative-Ring : | ||
is-closed-under-right-multiplication-subset-Commutative-Ring A | ||
subset-full-ideal-Commutative-Ring | ||
is-closed-under-right-multiplication-full-ideal-Commutative-Ring = | ||
is-closed-under-right-multiplication-full-ideal-Ring | ||
( ring-Commutative-Ring A) | ||
|
||
is-left-ideal-full-ideal-Commutative-Ring : | ||
is-left-ideal-subset-Commutative-Ring A subset-full-ideal-Commutative-Ring | ||
is-left-ideal-full-ideal-Commutative-Ring = | ||
is-left-ideal-full-ideal-Ring (ring-Commutative-Ring A) | ||
|
||
full-left-ideal-Commutative-Ring : left-ideal-Commutative-Ring lzero A | ||
full-left-ideal-Commutative-Ring = | ||
full-left-ideal-Ring (ring-Commutative-Ring A) | ||
|
||
is-right-ideal-full-ideal-Commutative-Ring : | ||
is-right-ideal-subset-Commutative-Ring A subset-full-ideal-Commutative-Ring | ||
is-right-ideal-full-ideal-Commutative-Ring = | ||
is-right-ideal-full-ideal-Ring (ring-Commutative-Ring A) | ||
|
||
full-right-ideal-Commutative-Ring : right-ideal-Commutative-Ring lzero A | ||
full-right-ideal-Commutative-Ring = | ||
full-right-ideal-Ring (ring-Commutative-Ring A) | ||
|
||
is-ideal-full-ideal-Commutative-Ring : | ||
is-ideal-subset-Commutative-Ring A subset-full-ideal-Commutative-Ring | ||
is-ideal-full-ideal-Commutative-Ring = | ||
is-ideal-full-ideal-Ring (ring-Commutative-Ring A) | ||
|
||
full-ideal-Commutative-Ring : ideal-Commutative-Ring lzero A | ||
full-ideal-Commutative-Ring = full-ideal-Ring (ring-Commutative-Ring A) | ||
|
||
is-full-full-ideal-Commutative-Ring : | ||
is-full-ideal-Commutative-Ring A full-ideal-Commutative-Ring | ||
is-full-full-ideal-Commutative-Ring = | ||
is-full-full-ideal-Ring (ring-Commutative-Ring A) | ||
``` | ||
|
||
## Properties | ||
|
||
### Any ideal is full if and only if it contains `1` | ||
|
||
```agda | ||
module _ | ||
{l1 l2 : Level} (A : Commutative-Ring l1) (I : ideal-Commutative-Ring l2 A) | ||
where | ||
|
||
is-full-contains-one-ideal-Commutative-Ring : | ||
is-in-ideal-Commutative-Ring A I (one-Commutative-Ring A) → | ||
is-full-ideal-Commutative-Ring A I | ||
is-full-contains-one-ideal-Commutative-Ring = | ||
is-full-contains-one-ideal-Ring (ring-Commutative-Ring A) I | ||
|
||
contains-one-is-full-ideal-Commutative-Ring : | ||
is-full-ideal-Commutative-Ring A I → | ||
is-in-ideal-Commutative-Ring A I (one-Commutative-Ring A) | ||
contains-one-is-full-ideal-Commutative-Ring = | ||
contains-one-is-full-ideal-Ring (ring-Commutative-Ring A) I | ||
``` | ||
|
||
### Any ideal is full if and only if it is a top element in the large poset of ideals | ||
|
||
```agda | ||
module _ | ||
{l1 l2 : Level} (A : Commutative-Ring l1) (I : ideal-Commutative-Ring l2 A) | ||
where | ||
|
||
is-full-is-top-element-ideal-Commutative-Ring : | ||
is-top-element-Large-Poset (ideal-Commutative-Ring-Large-Poset A) I → | ||
is-full-ideal-Commutative-Ring A I | ||
is-full-is-top-element-ideal-Commutative-Ring = | ||
is-full-is-top-element-ideal-Ring (ring-Commutative-Ring A) I | ||
|
||
is-top-element-is-full-ideal-Commutative-Ring : | ||
is-full-ideal-Commutative-Ring A I → | ||
is-top-element-Large-Poset (ideal-Commutative-Ring-Large-Poset A) I | ||
is-top-element-is-full-ideal-Commutative-Ring = | ||
is-top-element-is-full-ideal-Ring (ring-Commutative-Ring A) I | ||
|
||
module _ | ||
{l1 : Level} (A : Commutative-Ring l1) | ||
where | ||
|
||
is-top-element-full-ideal-Commutative-Ring : | ||
is-top-element-Large-Poset | ||
( ideal-Commutative-Ring-Large-Poset A) | ||
( full-ideal-Commutative-Ring A) | ||
is-top-element-full-ideal-Commutative-Ring = | ||
is-top-element-full-ideal-Ring (ring-Commutative-Ring A) | ||
|
||
has-top-element-ideal-Commutative-Ring : | ||
has-top-element-Large-Poset (ideal-Commutative-Ring-Large-Poset A) | ||
has-top-element-ideal-Commutative-Ring = | ||
has-top-element-ideal-Ring (ring-Commutative-Ring A) | ||
``` | ||
|
||
### The full ideal of a commutative ring is radical | ||
|
||
```agda | ||
module _ | ||
{l1 : Level} (A : Commutative-Ring l1) | ||
where | ||
|
||
is-radical-full-ideal-Commutative-Ring : | ||
is-radical-ideal-Commutative-Ring A (full-ideal-Commutative-Ring A) | ||
is-radical-full-ideal-Commutative-Ring x n H = raise-star | ||
|
||
full-radical-ideal-Commutative-Ring : radical-ideal-Commutative-Ring lzero A | ||
pr1 full-radical-ideal-Commutative-Ring = | ||
full-ideal-Commutative-Ring A | ||
pr2 full-radical-ideal-Commutative-Ring = | ||
is-radical-full-ideal-Commutative-Ring | ||
|
||
is-top-element-full-radical-ideal-Commutative-Ring : | ||
is-top-element-Large-Poset | ||
( radical-ideal-Commutative-Ring-Large-Poset A) | ||
( full-radical-ideal-Commutative-Ring) | ||
is-top-element-full-radical-ideal-Commutative-Ring I = | ||
is-top-element-full-ideal-Commutative-Ring A | ||
( ideal-radical-ideal-Commutative-Ring A I) | ||
|
||
has-top-element-radical-ideal-Commutative-Ring : | ||
has-top-element-Large-Poset | ||
( radical-ideal-Commutative-Ring-Large-Poset A) | ||
top-has-top-element-Large-Poset | ||
has-top-element-radical-ideal-Commutative-Ring = | ||
full-radical-ideal-Commutative-Ring | ||
is-top-element-top-has-top-element-Large-Poset | ||
has-top-element-radical-ideal-Commutative-Ring = | ||
is-top-element-full-radical-ideal-Commutative-Ring | ||
``` |
Oops, something went wrong.