We know that the algebraic automorphisms of the real numbers under addition is not in 1:1 correpondence with R∖{0}; see here.
The argument uses the AOC.
Suppose we drop the AOC from ZFC replacing it with
Axiom (GR):
The injective mapping
Φ:R∖{0}→AutomorphismGroup(R,+)
is surjective.
Has this ZF+GR been tried and/or does this lead to 1=0?
Update:
Added descriptive set theory tag after looking over links in Noah's answer.
Answer
It is indeed consistent, and in fact is a consequence of the extremely powerful axiom of determinacy.
Specifically, AD implies that every homomorphism from (R,+) to itself is continuous, and in particular of the form a↦ar for some r∈R. See here for some discussion of how nasty any other endomorphism would have to be; AD rules out such sets (e.g. implies that every set of reals is measurable).
Of course, as Asaf observes below, AD is truly massive overkill (like, nuking a mosquito); I'm mentioning it because AD is a natural alternative to AC which you may independently want to know about.
Now AD isn't actually cheap: the theory ZF+AD proves the consistency of ZF, that is, the axiom determinacy is of high consistency strength. We can prove the consistency of ZF+GR relative to ZF alone; however, this is a bit more technical.
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