Metamath Proof Explorer


Definition df-qmap

Description: Define the quotient map (coset map), see also dfqmap2 and dfqmap3 . QMap R is the "send a generator / domain element to its R -coset" map: it maps each x e. dom R to the block [ x ] R . Makes the quotient operation /. structurally explicit as the range of a canonical map (see dfqs2 , rnqmap ). This is crucial for

(i) modular "two-layer" characterizations (map layer + carrier layer) such as dfdisjs6 / dfdisjs7 ,

(ii) transport of properties between a relation and its induced quotient-carrier (e.g. "elements are blocks" via rnqmap ), and

(iii) expressing stability/invariance constraints as ordinary conditions on a graph (e.g. ran QMap r e. ElDisjs , QMap r e. Disjs ). (Contributed by Peter Mazsa, 12-Feb-2026)

Ref Expression
Assertion df-qmap Could not format assertion : No typesetting found for |- QMap R = ( x e. dom R |-> [ x ] R ) with typecode |-

Detailed syntax breakdown

Step Hyp Ref Expression
0 cR class R
1 0 cqmap Could not format QMap R : No typesetting found for class QMap R with typecode class
2 vx setvar x
3 0 cdm class dom R
4 2 cv setvar x
5 4 0 cec class x R
6 2 3 5 cmpt class x dom R x R
7 1 6 wceq Could not format QMap R = ( x e. dom R |-> [ x ] R ) : No typesetting found for wff QMap R = ( x e. dom R |-> [ x ] R ) with typecode wff