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LSpice
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Suppose $f:C\to C$ is a homeomorphism, where $C=\{0,1\}^{\mathbb N}$ is Cantor space. Suppose $f$ preserves $=^*$ (equality on all but finitely many coordinates). Does it follow that $f$ also reflects $=^*$? That is, if $$x=^* y \implies f(x)=^* f(y)$$ does it follow that: $$x=^* y \iff f(x)=^* f(y)?$$

Using Axiom of Choice we can show that a bijection of $C$ that preserves $=^*$ need not reflect $=^*$, so the continuity assumptions are not superfluous...

Suppose $f:C\to C$ is a homeomorphism, where $C=\{0,1\}^{\mathbb N}$ is Cantor space. Suppose $f$ preserves $=^*$ (equality on all but finitely many coordinates). Does it follow that $f$ also reflects $=^*$? That is, if $$x=^* y \implies f(x)=^* f(y)$$ does it follow that: $$x=^* y \iff f(x)=^* f(y)?$$

Using Axiom of Choice we can show that a bijection of $C$ that preserves $=^*$ need not reflect $=^*$, so the continuity assumptions are not superfluous...

Suppose $f:C\to C$ is a homeomorphism, where $C=\{0,1\}^{\mathbb N}$ is Cantor space. Suppose $f$ preserves $=^*$ (equality on all but finitely many coordinates). Does it follow that $f$ also reflects $=^*$? That is, if $$x=^* y \implies f(x)=^* f(y)$$ does it follow that: $$x=^* y \iff f(x)=^* f(y)?$$

Using Axiom of Choice we can show that a bijection of $C$ that preserves $=^*$ need not reflect $=^*$, so the continuity assumptions are not superfluous.

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Bjørn Kjos-Hanssen
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Suppose $f:C\to C$ is a homeomorphism, where $C=\{0,1\}^{\mathbb N}$ is Cantor space. If Suppose $x=^* y$ implies$f$ preserves $f(x)=^* f(y)$$=^*$ (equalequality on all but finitely many coordinates) then is the same true for. Does it follow that $f^{-1}$$f$ also reflects $=^*$? That is, if $$x=^* y \implies f(x)=^* f(y)$$ does it follow that: $$x=^* y \iff f(x)=^* f(y)?$$

I know it fails without the homeorphism assumption if we useUsing Axiom of Choice we can show that a bijection of $C$ that preserves $=^*$ need not reflect $=^*$, for instanceso the continuity assumptions are not superfluous...

Suppose $f:C\to C$ is a homeomorphism, where $C=\{0,1\}^{\mathbb N}$ is Cantor space. If $x=^* y$ implies $f(x)=^* f(y)$ (equal on all but finitely many coordinates) then is the same true for $f^{-1}$?

I know it fails without the homeorphism assumption if we use Axiom of Choice, for instance...

Suppose $f:C\to C$ is a homeomorphism, where $C=\{0,1\}^{\mathbb N}$ is Cantor space. Suppose $f$ preserves $=^*$ (equality on all but finitely many coordinates). Does it follow that $f$ also reflects $=^*$? That is, if $$x=^* y \implies f(x)=^* f(y)$$ does it follow that: $$x=^* y \iff f(x)=^* f(y)?$$

Using Axiom of Choice we can show that a bijection of $C$ that preserves $=^*$ need not reflect $=^*$, so the continuity assumptions are not superfluous...

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Bjørn Kjos-Hanssen
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Homeomorphisms and "mod finite"

Suppose $f:C\to C$ is a homeomorphism, where $C=\{0,1\}^{\mathbb N}$ is Cantor space. If $x=^* y$ implies $f(x)=^* f(y)$ (equal on all but finitely many coordinates) then is the same true for $f^{-1}$?

I know it fails without the homeorphism assumption if we use Axiom of Choice, for instance...