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Let $\mathcal{F}$ be a non-principal ultrafilter on $\omega$. Let $^*\mathbb{N}$ = $\mathbb{N}^\omega/\mathcal{F}$ be an ultrapower. Let $\{n_\alpha\}_{\alpha\in\omega_1}$ be a strictly increasing sequence in $^*\mathbb{N}$ with the following properties:.

  1. It is strictly increasing.
  2. $\forall \alpha \in \omega_1,\; n_{\alpha+1} = n_\alpha + 1$.

Assuming ZFC, would this sequence be unbounded in $^*\mathbb{N}$, i.e. $\forall n \in {^*\mathbb{N}}\ \exists \alpha \in \omega_1\ n_\alpha > n $? Does it depend on CH?

Let $\mathcal{F}$ be a non-principal ultrafilter on $\omega$. Let $^*\mathbb{N}$ = $\mathbb{N}^\omega/\mathcal{F}$ be an ultrapower. Let $\{n_\alpha\}_{\alpha\in\omega_1}$ be a sequence in $^*\mathbb{N}$ with the following properties:

  1. It is strictly increasing.
  2. $\forall \alpha \in \omega_1,\; n_{\alpha+1} = n_\alpha + 1$.

Assuming ZFC, would this sequence be unbounded in $^*\mathbb{N}$, i.e. $\forall n \in {^*\mathbb{N}}\ \exists \alpha \in \omega_1\ n_\alpha > n $? Does it depend on CH?

Let $\mathcal{F}$ be a non-principal ultrafilter on $\omega$. Let $^*\mathbb{N}$ = $\mathbb{N}^\omega/\mathcal{F}$ be an ultrapower. Let $\{n_\alpha\}_{\alpha\in\omega_1}$ be a strictly increasing sequence in $^*\mathbb{N}$.

Assuming ZFC, would this sequence be unbounded in $^*\mathbb{N}$, i.e. $\forall n \in {^*\mathbb{N}}\ \exists \alpha \in \omega_1\ n_\alpha > n $? Does it depend on CH?

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Unbounded $\omega_1$ sequence-sequence in $*\mathbb$^*\mathbb{N}$

Let $\mathcal{F}$ be a non-principal ultrafilter on $\omega$. Let $*\mathbb{N}$$^*\mathbb{N}$ = $\mathbb{N}^\omega/\mathcal{F}$ be an ultrapower. Let $\{n_\alpha\}_{\alpha\in\omega_1}$ be a sequence in the $*\mathbb{N}$$^*\mathbb{N}$ with the following properties:

  1. It is strictly increasing.
  2. $\forall \alpha \in \omega_1\ n_{\alpha+1} = n_\alpha + 1$$\forall \alpha \in \omega_1,\; n_{\alpha+1} = n_\alpha + 1$.

Assuming ZFC, would this sequence be unbounded in the $*\mathbb{N}$$^*\mathbb{N}$, i.e. $\forall n \in *\mathbb{N}\ \exists \alpha \in \omega_1\ n_\alpha > n $$\forall n \in {^*\mathbb{N}}\ \exists \alpha \in \omega_1\ n_\alpha > n $? Does it depend on CH?

Unbounded $\omega_1$ sequence in $*\mathbb{N}$

Let $\mathcal{F}$ be a non-principal ultrafilter on $\omega$. Let $*\mathbb{N}$ = $\mathbb{N}^\omega/\mathcal{F}$ be an ultrapower. Let $\{n_\alpha\}_{\alpha\in\omega_1}$ be a sequence in the $*\mathbb{N}$ with the following properties:

  1. It is strictly increasing.
  2. $\forall \alpha \in \omega_1\ n_{\alpha+1} = n_\alpha + 1$.

Assuming ZFC, would this sequence be unbounded in the $*\mathbb{N}$, i.e. $\forall n \in *\mathbb{N}\ \exists \alpha \in \omega_1\ n_\alpha > n $? Does it depend on CH?

Unbounded $\omega_1$-sequence in $^*\mathbb{N}$

Let $\mathcal{F}$ be a non-principal ultrafilter on $\omega$. Let $^*\mathbb{N}$ = $\mathbb{N}^\omega/\mathcal{F}$ be an ultrapower. Let $\{n_\alpha\}_{\alpha\in\omega_1}$ be a sequence in $^*\mathbb{N}$ with the following properties:

  1. It is strictly increasing.
  2. $\forall \alpha \in \omega_1,\; n_{\alpha+1} = n_\alpha + 1$.

Assuming ZFC, would this sequence be unbounded in $^*\mathbb{N}$, i.e. $\forall n \in {^*\mathbb{N}}\ \exists \alpha \in \omega_1\ n_\alpha > n $? Does it depend on CH?

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Unbounded $\omega_1$ sequence in $*\mathbb{N}$

Let $\mathcal{F}$ be a non-principal ultrafilter on $\omega$. Let $*\mathbb{N}$ = $\mathbb{N}^\omega/\mathcal{F}$ be an ultrapower. Let $\{n_\alpha\}_{\alpha\in\omega_1}$ be a sequence in the $*\mathbb{N}$ with the following properties:

  1. It is strictly increasing.
  2. $\forall \alpha \in \omega_1\ n_{\alpha+1} = n_\alpha + 1$.

Assuming ZFC, would this sequence be unbounded in the $*\mathbb{N}$, i.e. $\forall n \in *\mathbb{N}\ \exists \alpha \in \omega_1\ n_\alpha > n $? Does it depend on CH?