- 1

- 0

**Need help in some "inter-dimensional isomorphisms"**

consider the set

M = {e^(i*arctan(x)) in

**C**| x in

**R**}

now it is obvious that M is isomorphic to the real line, so we have an isomorphism from a subset of 2D to 1D.

ok, now we should have M x M isomorphic to

**R**^2, but somehow I cannot do this rigorously (excuse the spelling? :)

what I do know (if there is no mistake in my working :) is that M x M is a hollow torus (doughnut :) in

**R**^4 or

**C**^2 if one allows x to be infinity in the definition

if there are anyone willing to help - i will nbe greatly indebted