>>>A general isomorphism cannot exist since R is an ordered field but C is not...
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>>Why isn't C ordered?
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>The order axioms aren't satisfied. For example, is i greater than -i?
We can set an order defined as follows:
z1 <= z2 iif ((y1 < y2) or ((y1 = y2) and (x1 <= x2)))
Where z=x+y*i (or zk=xk+yk*i). (k is an indice)
This relation is reflexive, tranzitive and antisymetric. So, C can be ordered.
Anyway, the fact that we don't have an order on a set doesn't mean it cannot be isomorphic with a set for which we have an order.
As an example, we can have an isomorphism between a circle and R. R is ordered, but we don't have (usual) an order on a circle.
Vlad
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