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I have studystudied in Hatcher ( AlgebraicAlgebraic topology, p.169) an homological proof of the Jordan theorem. Then I would like to understand an upgrade of this theorem :, the Schoenflies version. 
On my way to prove it, I have studied the idea of using the Caratheodory theorem. Even if I can understand this one, I am completely unable to conclude.

The common idea (that is shared on internet), is to use the conformal mapping property, and I agree with that. But here is the problem, as everything related to the Jordan theorem, the fact that a Jordan domain is simply connected seems clear, but the demonstration is not.

So, I tried to prove this assertion. Here is my first idea  : 
In the Hatcher's proof of Jordan theorem, we saw that $$H_i(\mathbb{S}^2 - h(\mathbb{S}^1))=0$$ Except for $i =2-1-1=0$ (here $h$ is any continuous function). So $H_1(G)=0$ where $G$ is the bounded component of $\mathbb{R}^2-\mathbb{S}^1$. However, this is not a characterization of simple connectedness, we would like to have the save result but with $\pi_1(G)$. So there is my question, does someone know (a link to) a profproof that $$ \pi_1(G)=0 ?$$ It can be a rather conceptual explanation, I would like it.

Furthermore, I have heard about a definition of simple connectedness with Jordan curves, but I don't know how to prove it either.

Thank you

I have study in Hatcher ( Algebraic topology, p.169) an homological proof of the Jordan theorem. Then I would like to understand an upgrade of this theorem : the Schoenflies version. On my way to prove it, I have studied the idea of using the Caratheodory theorem. Even if I can understand this one, I am completely unable to conclude.

The common idea (that is shared on internet), is to use the conformal mapping property, and I agree with that. But here is the problem, as everything related to the Jordan theorem, the fact that a Jordan domain is simply connected seems clear, but the demonstration is not.

So, I tried to prove this assertion. Here is my first idea  : In the Hatcher's proof of Jordan theorem, we saw that $$H_i(\mathbb{S}^2 - h(\mathbb{S}^1))=0$$ Except for $i =2-1-1=0$ (here $h$ is any continuous function). So $H_1(G)=0$ where $G$ is the bounded component of $\mathbb{R}^2-\mathbb{S}^1$. However, this is not a characterization of simple connectedness, we would like to have the save result but with $\pi_1(G)$. So there is my question, does someone know (a link to) a prof that $$ \pi_1(G)=0 ?$$ It can be a rather conceptual explanation, I would like it.

Furthermore, I have heard about a definition of simple connectedness with Jordan curves, but I don't know how to prove it either.

Thank you

I have studied in Hatcher (Algebraic topology, p.169) an homological proof of the Jordan theorem. I would like to understand an upgrade of this theorem, the Schoenflies version. 
On my way to prove it, I have studied the idea of using the Caratheodory theorem. Even if I can understand this one, I am completely unable to conclude.

The common idea (that is shared on internet), is to use the conformal mapping property, and I agree with that. But here is the problem, as everything related to the Jordan theorem, the fact that a Jordan domain is simply connected seems clear, but the demonstration is not.

So, I tried to prove this assertion. Here is my first idea: 
In the Hatcher's proof of Jordan theorem, we saw that $$H_i(\mathbb{S}^2 - h(\mathbb{S}^1))=0$$ Except for $i =2-1-1=0$ (here $h$ is any continuous function). So $H_1(G)=0$ where $G$ is the bounded component of $\mathbb{R}^2-\mathbb{S}^1$. However, this is not a characterization of simple connectedness, we would like to have the save result but with $\pi_1(G)$. So there is my question, does someone know (a link to) a proof that $$ \pi_1(G)=0 ?$$ It can be a rather conceptual explanation, I would like it.

Furthermore, I have heard about a definition of simple connectedness with Jordan curves, but I don't know how to prove it either.

Thank you

removed capitals from title, fixed English (substantive of "simply X" is "simple Xness")
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Conceptual proof of the simply-connectednesssimple connectedness of a Jordan Domaindomain

I have study in Hatcher ( Algebraic topology, p.169) an homological proof of the Jordan theorem. Then I would like to understand an upgrade of this theorem : the Schoenflies version. On my way to prove it, I have studied the idea of using the Caratheodory theorem. Even if I can understand this one, I am completlycompletely unable to conclude.

The common idea (that is shared on internet), is to use the conformal mapping property, and I agree with that. But here is the problem, as everything related to the Jordan theorem, the fact that a Jordan domain is simply-connected connected seems clear, but the demonstration is not.

So, I tried to prove this assertion. Here is my first idea : In the Hatcher's proof of Jordan theorem, we saw that $$H_i(\mathbb{S}^2 - h(\mathbb{S}^1))=0$$ Except for $i =2-1-1=0$ (here $h$ is any continuous function). So $H_1(G)=0$ where $G$ is the bounded component of $\mathbb{R}^2-\mathbb{S}^1$. However, this is not a characterization of simply-connectednesssimple connectedness, we would like to have the save result but with $\pi_1(G)$. So there is my question, does someone know (a link to) a prof that $$ \pi_1(G)=0 ?$$ It can be a rather conceptual explanation, I would like it.

Furthermore, I have heard about ana definition of simple-connectedness connectedness with Jordan curves, but I don't know how to prove it either.

Thank you

Conceptual proof of the simply-connectedness of a Jordan Domain

I have study in Hatcher ( Algebraic topology, p.169) an homological proof of the Jordan theorem. Then I would like to understand an upgrade of this theorem : the Schoenflies version. On my way to prove it, I have studied the idea of using the Caratheodory theorem. Even if I can understand this one, I am completly unable to conclude.

The common idea (that is shared on internet), is to use the conformal mapping property, and I agree with that. But here is the problem, as everything related to the Jordan theorem, the fact that a Jordan domain is simply-connected seems clear, but the demonstration is not.

So, I tried to prove this assertion. Here is my first idea : In the Hatcher's proof of Jordan theorem, we saw that $$H_i(\mathbb{S}^2 - h(\mathbb{S}^1))=0$$ Except for $i =2-1-1=0$ (here $h$ is any continuous function). So $H_1(G)=0$ where $G$ is the bounded component of $\mathbb{R}^2-\mathbb{S}^1$. However, this is not a characterization of simply-connectedness, we would like to have the save result but with $\pi_1(G)$. So there is my question, does someone know (a link to) a prof that $$ \pi_1(G)=0 ?$$ It can be a rather conceptual explanation, I would like it.

Furthermore, I have heard about an definition of simple-connectedness with Jordan curves, but I don't know how to prove it either.

Thank you

Conceptual proof of the simple connectedness of a Jordan domain

I have study in Hatcher ( Algebraic topology, p.169) an homological proof of the Jordan theorem. Then I would like to understand an upgrade of this theorem : the Schoenflies version. On my way to prove it, I have studied the idea of using the Caratheodory theorem. Even if I can understand this one, I am completely unable to conclude.

The common idea (that is shared on internet), is to use the conformal mapping property, and I agree with that. But here is the problem, as everything related to the Jordan theorem, the fact that a Jordan domain is simply connected seems clear, but the demonstration is not.

So, I tried to prove this assertion. Here is my first idea : In the Hatcher's proof of Jordan theorem, we saw that $$H_i(\mathbb{S}^2 - h(\mathbb{S}^1))=0$$ Except for $i =2-1-1=0$ (here $h$ is any continuous function). So $H_1(G)=0$ where $G$ is the bounded component of $\mathbb{R}^2-\mathbb{S}^1$. However, this is not a characterization of simple connectedness, we would like to have the save result but with $\pi_1(G)$. So there is my question, does someone know (a link to) a prof that $$ \pi_1(G)=0 ?$$ It can be a rather conceptual explanation, I would like it.

Furthermore, I have heard about a definition of simple connectedness with Jordan curves, but I don't know how to prove it either.

Thank you

Source Link

Conceptual proof of the simply-connectedness of a Jordan Domain

I have study in Hatcher ( Algebraic topology, p.169) an homological proof of the Jordan theorem. Then I would like to understand an upgrade of this theorem : the Schoenflies version. On my way to prove it, I have studied the idea of using the Caratheodory theorem. Even if I can understand this one, I am completly unable to conclude.

The common idea (that is shared on internet), is to use the conformal mapping property, and I agree with that. But here is the problem, as everything related to the Jordan theorem, the fact that a Jordan domain is simply-connected seems clear, but the demonstration is not.

So, I tried to prove this assertion. Here is my first idea : In the Hatcher's proof of Jordan theorem, we saw that $$H_i(\mathbb{S}^2 - h(\mathbb{S}^1))=0$$ Except for $i =2-1-1=0$ (here $h$ is any continuous function). So $H_1(G)=0$ where $G$ is the bounded component of $\mathbb{R}^2-\mathbb{S}^1$. However, this is not a characterization of simply-connectedness, we would like to have the save result but with $\pi_1(G)$. So there is my question, does someone know (a link to) a prof that $$ \pi_1(G)=0 ?$$ It can be a rather conceptual explanation, I would like it.

Furthermore, I have heard about an definition of simple-connectedness with Jordan curves, but I don't know how to prove it either.

Thank you