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Redid question with equivalency
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Keith Millar
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What strengthenings of measurability does the Mostowski collapse of the ultrapowers possess?

Here's whatOk, I meanalready posted this question, but a couple of notational errors and assumptions were made in the previous version. Let $j:V\rightarrow M$Hopefully, this new equivalent version will be an elementary embedding with critical point $\kappa$ where $P(M)$ holds (given some third order predicate)better understood. 

Let $MO$$U$ be the Mostowski collapse of $Ult_U(V)$ for somea nonprinciple $\kappa$$\lambda$-complete ultrafilter $U$. When does $P(MO)$ also hold?

A perfect example is measurability itself. $j$ has critical pointover $\kappa$$\lambda$. Letting Let $P(M)$ be "there is an elementary embedding$\pi_U(f)$ for a function $j_0:V\rightarrow M$$f$ with critical pointdomain $\kappa$", it can$\lambda$ be seen thatdefined as follows: $$\pi_U(f)=\{\pi_U(g):\{\alpha<\lambda:g(\alpha)\in f(\alpha)\}\in U\}$$

Let $M$ holds iffbe $MO$ holds$\{\pi_U(f):\mathrm{Dom}(f)=\lambda\}$. Finally, let $\lambda_0=\lambda$ and: $$\lambda_{n+1}=|\{\pi_U(f):\{\alpha<\lambda:g(\alpha)\in \lambda_n\}\in U\}|$$

But does it hold forThen, which of the following strengthenings of measurability?are always true:

  • LetIf $\kappa$ be$\lambda$ is $\theta$-strong. Is, then $V_\theta\subset MO$?$V_\theta\subset M$.
  • LetIf $\kappa$ be$\lambda$ is $\theta$-supercompact. Is, then $MO^\theta\subset MO$?$M^\theta\subset M$.
  • LetIf $\kappa$ be$\lambda$ is $n$-superstrong, and $j_0:V\rightarrow MO$ be the composition of the mostowski collapse function (between the ultrapower and $MO$)then $\pi$ to the canonical ultrapower embedding$V_{\lambda_n}\subset M$. Is $V_{j_0^n(\kappa)}\subset MO$?
  • LetIf $\kappa$ be$\lambda$ is $n$-huge, and $j_0:V\rightarrow MO$ be the composition of the mostowski collapse function (between the ultrapower and $MO$)then $\pi$ to the canonical ultrapower embedding$M^{\lambda_n}\subset M$. Is $MO^{j_0^n(\kappa)}\subset MO$?

What strengthenings of measurability does the Mostowski collapse of the ultrapowers possess?

Here's what I mean. Let $j:V\rightarrow M$ be an elementary embedding with critical point $\kappa$ where $P(M)$ holds (given some third order predicate). Let $MO$ be the Mostowski collapse of $Ult_U(V)$ for some nonprinciple $\kappa$-complete ultrafilter $U$. When does $P(MO)$ also hold?

A perfect example is measurability itself. $j$ has critical point $\kappa$. Letting $P(M)$ be "there is an elementary embedding $j_0:V\rightarrow M$ with critical point $\kappa$", it can be seen that $M$ holds iff $MO$ holds.

But does it hold for the following strengthenings of measurability?

  • Let $\kappa$ be $\theta$-strong. Is $V_\theta\subset MO$?
  • Let $\kappa$ be $\theta$-supercompact. Is $MO^\theta\subset MO$?
  • Let $\kappa$ be $n$-superstrong, and $j_0:V\rightarrow MO$ be the composition of the mostowski collapse function (between the ultrapower and $MO$) $\pi$ to the canonical ultrapower embedding. Is $V_{j_0^n(\kappa)}\subset MO$?
  • Let $\kappa$ be $n$-huge, and $j_0:V\rightarrow MO$ be the composition of the mostowski collapse function (between the ultrapower and $MO$) $\pi$ to the canonical ultrapower embedding. Is $MO^{j_0^n(\kappa)}\subset MO$?

What strengthenings of measurability does the Mostowski collapse of the ultrapowers possess?

Ok, I already posted this question, but a couple of notational errors and assumptions were made in the previous version. Hopefully, this new equivalent version will be better understood. 

Let $U$ be a nonprinciple $\lambda$-complete ultrafilter over $\lambda$. Let $\pi_U(f)$ for a function $f$ with domain $\lambda$ be defined as follows: $$\pi_U(f)=\{\pi_U(g):\{\alpha<\lambda:g(\alpha)\in f(\alpha)\}\in U\}$$

Let $M$ be $\{\pi_U(f):\mathrm{Dom}(f)=\lambda\}$. Finally, let $\lambda_0=\lambda$ and: $$\lambda_{n+1}=|\{\pi_U(f):\{\alpha<\lambda:g(\alpha)\in \lambda_n\}\in U\}|$$

Then, which of the following are always true:

  • If $\lambda$ is $\theta$-strong, then $V_\theta\subset M$.
  • If $\lambda$ is $\theta$-supercompact, then $M^\theta\subset M$.
  • If $\lambda$ is $n$-superstrong, then $V_{\lambda_n}\subset M$.
  • If $\lambda$ is $n$-huge, then $M^{\lambda_n}\subset M$.
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Andrés E. Caicedo
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What strengthenings of measurability doesdo the Mostowski collapsecollapses of ultrapowers possess?

What strengthenings of measurability dodoes the Mostowski collapse of the ultrapowers possespossess?

What strengthenings of measurability does the Mostowski collapse of the ultrapowers possess?

Here's what I mean. Let $j:V\rightarrow M$ be an elementary embedding with critical point $\kappa$ where $P(M)$ holds (given some third order predicate). Let $MO$ be the Mostowski collapse of $Ult_U(V)$ for some nonprinciple $\kappa$-complete ultrafilter $U$. When does $P(MO)$ also hold?

A perfect example is measurability itself. $j$ has critical point $\kappa$. Letting $P(M)$ be "there is an elementary embedding $j_0:V\rightarrow M$ with critical point $\kappa$", it can be seen that $M$ holds iff $MO$ holds.

But does it hold for the following strengthenings of measurability?

  • Let $\kappa$ be $\theta$-strong. Is $V_\theta\subset MO$?
  • Let $\kappa$ be $\theta$-supercompact. Is $MO^\theta\subset MO$?
  • Let $\kappa$ be $n$-superstrong, and $j_0:V\rightarrow MO$ be the composition of the mostowski collapse function (between the ultrapower and $MO$) $\pi$ to the canonical ultrapower embedding. Is $V_{j_0^n(\kappa)}\subset MO$?
  • Let $\kappa$ be $n$-huge, and $j_0:V\rightarrow MO$ be the composition of the mostowski collapse function (between the ultrapower and $MO$) $\pi$ to the canonical ultrapower embedding. Is $MO^{j_0^n(\kappa)}\subset MO$?

What strengthenings of measurability do the Mostowski collapse of the ultrapowers posses?

Here's what I mean. Let $j:V\rightarrow M$ be an elementary embedding with critical point $\kappa$ where $P(M)$ holds (given some third order predicate). Let $MO$ be the Mostowski collapse of $Ult_U(V)$ for some nonprinciple $\kappa$-complete ultrafilter $U$. When does $P(MO)$ also hold?

A perfect example is measurability itself. $j$ has critical point $\kappa$. Letting $P(M)$ be "there is an elementary embedding $j_0:V\rightarrow M$ with critical point $\kappa$", it can be seen that $M$ holds iff $MO$ holds.

But does it hold for the following strengthenings of measurability?

  • Let $\kappa$ be $\theta$-strong. Is $V_\theta\subset MO$?
  • Let $\kappa$ be $\theta$-supercompact. Is $MO^\theta\subset MO$?
  • Let $\kappa$ be $n$-superstrong, and $j_0:V\rightarrow MO$ be the composition of the mostowski collapse function (between the ultrapower and $MO$) $\pi$ to the canonical ultrapower embedding. Is $V_{j_0^n(\kappa)}\subset MO$?
  • Let $\kappa$ be $n$-huge, and $j_0:V\rightarrow MO$ be the composition of the mostowski collapse function (between the ultrapower and $MO$) $\pi$ to the canonical ultrapower embedding. Is $MO^{j_0^n(\kappa)}\subset MO$?

What strengthenings of measurability does the Mostowski collapse of ultrapowers possess?

What strengthenings of measurability does the Mostowski collapse of the ultrapowers possess?

Here's what I mean. Let $j:V\rightarrow M$ be an elementary embedding with critical point $\kappa$ where $P(M)$ holds (given some third order predicate). Let $MO$ be the Mostowski collapse of $Ult_U(V)$ for some nonprinciple $\kappa$-complete ultrafilter $U$. When does $P(MO)$ also hold?

A perfect example is measurability itself. $j$ has critical point $\kappa$. Letting $P(M)$ be "there is an elementary embedding $j_0:V\rightarrow M$ with critical point $\kappa$", it can be seen that $M$ holds iff $MO$ holds.

But does it hold for the following strengthenings of measurability?

  • Let $\kappa$ be $\theta$-strong. Is $V_\theta\subset MO$?
  • Let $\kappa$ be $\theta$-supercompact. Is $MO^\theta\subset MO$?
  • Let $\kappa$ be $n$-superstrong, and $j_0:V\rightarrow MO$ be the composition of the mostowski collapse function (between the ultrapower and $MO$) $\pi$ to the canonical ultrapower embedding. Is $V_{j_0^n(\kappa)}\subset MO$?
  • Let $\kappa$ be $n$-huge, and $j_0:V\rightarrow MO$ be the composition of the mostowski collapse function (between the ultrapower and $MO$) $\pi$ to the canonical ultrapower embedding. Is $MO^{j_0^n(\kappa)}\subset MO$?
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Keith Millar
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