- #1
math8
- 160
- 0
Is a projection a quotient map?
I think a quotient map is an onto map p:X-->Y (where X and Y are topological spaces) such that
U is open/closed in Y iff (p)-1(U) is open/closed in X.
And a projection is a map f:X-->X/~ defined by f(x)=[x] where [x] is the equivalent class (for a relation ~) containing x.
I guess a projection is onto because for every equivalent class [x], there is an x that maps to it, but I am wondering if every projection is a quotient map (or if every projection is continuous).
I think a quotient map is an onto map p:X-->Y (where X and Y are topological spaces) such that
U is open/closed in Y iff (p)-1(U) is open/closed in X.
And a projection is a map f:X-->X/~ defined by f(x)=[x] where [x] is the equivalent class (for a relation ~) containing x.
I guess a projection is onto because for every equivalent class [x], there is an x that maps to it, but I am wondering if every projection is a quotient map (or if every projection is continuous).