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Andrej Bauer
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Let $\; \mathbf{G} = \langle G,\cdot,\cal{T}\hspace{.06 in}\rangle \;$$\mathbf{G} = \langle G,\cdot,\mathcal{T}\;\rangle$ be a topological group. $\;\;$ LetLet $\mathbf{e}$ be the identity element of $\langle G,\cdot \rangle$.
  Assume $\{\mathbf{e}\}$ is closed in $\langle G,\cal{T}\hspace{.06 in}\rangle$$\langle G,\cal{T}\;\rangle$. $\;\;$ Then, I have managed to convince myself that:

a. $\;\;$ ZF proves that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is regular Haudorff.
b. $\;\;$ ZF + (Dependent Choice) $\;$ proves that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is completely regular.



  1. $\;$ ZF proves that $\langle G,\cal{T}\;\rangle$ is regular Haudorff.
  2. ZF + (Dependent Choice) proves that $\langle G,\cal{T}\;\rangle$ is completely regular.

My questions are:

  1. Are those right?


     
  2. $\;$ Does ZF prove that $\langle G,\cal{T}\hspace{.06 in}\rangle$$\langle G,\cal{T}\;\rangle$ is completely regular?


     
  3. $\;$ If no to question 2,
    does does assuming one or more of following the suffice for ZF to conclude that $\langle G,\cal{T}\hspace{.06 in}\rangle$$\langle G,\cal{T}\,\rangle$ is completely regular?

    (i) $\;$  
  4. $\mathbf{G}$ is two-sided complete
    (ii) $\;$  
  5. $\langle G,\cdot \rangle$ is abelian
    (iii) $\;$ 
  6. Countable Choice

Let $\; \mathbf{G} = \langle G,\cdot,\cal{T}\hspace{.06 in}\rangle \;$ be a topological group. $\;\;$ Let $\mathbf{e}$ be the identity element of $\langle G,\cdot \rangle$.
  Assume $\{\mathbf{e}\}$ is closed in $\langle G,\cal{T}\hspace{.06 in}\rangle$. $\;\;$ Then, I have managed to convince myself that:

a. $\;\;$ ZF proves that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is regular Haudorff.
b. $\;\;$ ZF + (Dependent Choice) $\;$ proves that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is completely regular.



  1. $\;$ Are those right?


     
  2. $\;$ Does ZF prove that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is completely regular?


     
  3. $\;$ If no to 2,
    does assuming one or more of following the suffice for ZF to conclude that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is completely regular?

    (i) $\;$ $\mathbf{G}$ is two-sided complete
    (ii) $\;$ $\langle G,\cdot \rangle$ is abelian
    (iii) $\;$ Countable Choice

Let $\mathbf{G} = \langle G,\cdot,\mathcal{T}\;\rangle$ be a topological group. Let $\mathbf{e}$ be the identity element of $\langle G,\cdot \rangle$. Assume $\{\mathbf{e}\}$ is closed in $\langle G,\cal{T}\;\rangle$. Then, I have managed to convince myself that:

  1. ZF proves that $\langle G,\cal{T}\;\rangle$ is regular Haudorff.
  2. ZF + (Dependent Choice) proves that $\langle G,\cal{T}\;\rangle$ is completely regular.

My questions are:

  1. Are those right?
  2. Does ZF prove that $\langle G,\cal{T}\;\rangle$ is completely regular?
  3. If no to question 2, does assuming one or more of following suffice for ZF to conclude that $\langle G,\cal{T}\,\rangle$ is completely regular? 
  4. $\mathbf{G}$ is two-sided complete 
  5. $\langle G,\cdot \rangle$ is abelian 
  6. Countable Choice
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user5810
user5810

Let $\; \mathbf{G} = \langle G,\cdot,\cal{T}\hspace{.06 in}\rangle \;$ be a topological group. $\;\;$ Let $\mathbf{e}$ be the identity element of $\langle G,\cdot \rangle$.
Assume $\{\mathbf{e}\}$ is closed in $\langle G,\cal{T}\hspace{.06 in}\rangle$. $\;\;$ Then, I have mangedmanaged to convince myself that:

a. $\;\;$ ZF proves that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is regular Haudorff.
b. $\;\;$ ZF + (Dependent Choice) $\;$ proves that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is completely regular.



  1. $\;$ Are those right?


  2. $\;$ Does ZF prove that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is completely regular?


  3. $\;$ If no to 2,
    does assuming one or more of following the suffice for ZF to conclude that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is completely regular?

    (i) $\;$ $\mathbf{G}$ is two-sided complete
    (ii) $\;$ $\langle G,\cdot \rangle$ is abelian
    (iii) $\;$ Countable Choice

Let $\; \mathbf{G} = \langle G,\cdot,\cal{T}\hspace{.06 in}\rangle \;$ be a topological group. $\;\;$ Let $\mathbf{e}$ be the identity element of $\langle G,\cdot \rangle$.
Assume $\{\mathbf{e}\}$ is closed in $\langle G,\cal{T}\hspace{.06 in}\rangle$. $\;\;$ Then, I have manged to convince myself that:

a. $\;\;$ ZF proves that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is regular Haudorff.
b. $\;\;$ ZF + (Dependent Choice) $\;$ proves that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is completely regular.



  1. $\;$ Are those right?


  2. $\;$ Does ZF prove that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is completely regular?


  3. $\;$ If no to 2,
    does assuming one or more of following the suffice for ZF to conclude that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is completely regular?

    (i) $\;$ $\mathbf{G}$ is two-sided complete
    (ii) $\;$ $\langle G,\cdot \rangle$ is abelian
    (iii) $\;$ Countable Choice

Let $\; \mathbf{G} = \langle G,\cdot,\cal{T}\hspace{.06 in}\rangle \;$ be a topological group. $\;\;$ Let $\mathbf{e}$ be the identity element of $\langle G,\cdot \rangle$.
Assume $\{\mathbf{e}\}$ is closed in $\langle G,\cal{T}\hspace{.06 in}\rangle$. $\;\;$ Then, I have managed to convince myself that:

a. $\;\;$ ZF proves that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is regular Haudorff.
b. $\;\;$ ZF + (Dependent Choice) $\;$ proves that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is completely regular.



  1. $\;$ Are those right?


  2. $\;$ Does ZF prove that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is completely regular?


  3. $\;$ If no to 2,
    does assuming one or more of following the suffice for ZF to conclude that $\langle G,\cal{T}\hspace{.06 in}\rangle$ is completely regular?

    (i) $\;$ $\mathbf{G}$ is two-sided complete
    (ii) $\;$ $\langle G,\cdot \rangle$ is abelian
    (iii) $\;$ Countable Choice
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François G. Dorais
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