Re: does 2^m=2^n imply m=n?

K.P.Hart wrote:

>It's truth is relative:
>the Generalized Continuum Hypothesis implies yes
>Martin's Axiom plus not-CH implies $2^{\aleph_0}=2^{\aleph_1}$
>Both are consistent with ZFC set theory.
>`Unprovable' describes the situation better.

Thank you and all who answered me!

By the way, what textbook (or article) contains that result?