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I'm trying to wrap my head around some of Harvey Friedman's recent, unpublished work on his tangible incompleteness project, and I'm trying to see the link between his "tangible statements" (propositions about subsets of $\mathbb{Q}[0,n]^k:=\{x\in\mathbb{Q}\;|\;0\leq x\leq n\}^k$ for $n,k\in\mathbb{N}$) and the large cardinals in the subtle/$k$-SRP range.

An example of the sort of statement he considers is the following (from this document):

Definition 1. $S\subseteq\mathbb{Q}[0,n]^k$ is an emulator of $E\subseteq\mathbb{Q}[0,n]^k$ if each element of $S^2$ is order equivalent to some member of $E^2$ (considered as subsets of $\mathbb{Q}[0,n]^{2k}$), where $x,y\in\mathbb{Q}[0,n]^k$ are said to be order equivalent if for any $1\leq i,j\leq k$, $x_i<x_j\leftrightarrow y_i<y_j$.

Definition 2. $A\subseteq\mathbb{Q}[0,n]^k$ is stable if and only if for all $p<1$, $\langle p,1,\ldots,k-1\rangle\in A\leftrightarrow\langle p,2,\ldots,k\rangle\in A$.

Example statement (called "MES" by Friedman). For all $k$, and all finite $E\subseteq\mathbb{Q}[0,k]^k$, there is a stable, $\subseteq$-maximal emulator of $E$.

Apparently MES implies $\mathrm{Con}(\mathsf{SRP})$ (where $\mathsf{SRP}$ is $\mathsf{ZFC}$+"there is a $k$-SRP cardinal" as an axiom scheme in $k$), so somehow there is a lot of strength happening in stable maximal emulators. And the relation to $k$-SRP cardinals, specifically, makes me think that emulators must be hiding a Ramsey condition under the hood, but I haven't been able to spot it yet.

How can I see what is happening with stable maximal emulators of finite subsets of $\mathbb{Q}[0,n]^k$ ($n,k>2$) that their guaranteed existence implies the consistency of the existence of large cardinals? [Edited to reflect JDH's correction in the comments.]

(For a reference on $k$-SRP cardinals, see Friedman, Harvey. Subtle cardinals and linear orderings. (English summary) Ann. Pure Appl. Logic 107 (2001), no. 1-3, 1–34.)

I'm trying to wrap my head around some of Harvey Friedman's recent, unpublished work on his tangible incompleteness project, and I'm trying to see the link between his "tangible statements" (propositions about subsets of $\mathbb{Q}[0,n]^k:=\{x\in\mathbb{Q}\;|\;0\leq x\leq n\}^k$ for $n,k\in\mathbb{N}$) and the large cardinals in the subtle/$k$-SRP range.

An example of the sort of statement he considers is the following (from this document):

Definition 1. $S\subseteq\mathbb{Q}[0,n]^k$ is an emulator of $E\subseteq\mathbb{Q}[0,n]^k$ if each element of $S^2$ is order equivalent to some member of $E^2$ (considered as subsets of $\mathbb{Q}[0,n]^{2k}$), where $x,y\in\mathbb{Q}[0,n]^k$ are said to be order equivalent if for any $1\leq i,j\leq k$, $x_i<x_j\leftrightarrow y_i<y_j$.

Definition 2. $A\subseteq\mathbb{Q}[0,n]^k$ is stable if and only if for all $p<1$, $\langle p,1,\ldots,k-1\rangle\in A\leftrightarrow\langle p,2,\ldots,k\rangle\in A$.

Example statement (called "MES" by Friedman). For all $k$, and all finite $E\subseteq\mathbb{Q}[0,k]^k$, there is a stable, $\subseteq$-maximal emulator of $E$.

Apparently MES implies $\mathrm{Con}(\mathsf{SRP})$ (where $\mathsf{SRP}$ is $\mathsf{ZFC}$+"there is a $k$-SRP cardinal" as an axiom scheme in $k$), so somehow there is a lot of strength happening in stable maximal emulators. And the relation to $k$-SRP cardinals, specifically, makes me think that emulators must be hiding a Ramsey condition under the hood, but I haven't been able to spot it yet.

How can I see what is happening with stable maximal emulators of finite subsets of $\mathbb{Q}[0,n]^k$ ($n,k>2$) that their guaranteed existence implies the existence of large cardinals?

(For a reference on $k$-SRP cardinals, see Friedman, Harvey. Subtle cardinals and linear orderings. (English summary) Ann. Pure Appl. Logic 107 (2001), no. 1-3, 1–34.)

I'm trying to wrap my head around some of Harvey Friedman's recent, unpublished work on his tangible incompleteness project, and I'm trying to see the link between his "tangible statements" (propositions about subsets of $\mathbb{Q}[0,n]^k:=\{x\in\mathbb{Q}\;|\;0\leq x\leq n\}^k$ for $n,k\in\mathbb{N}$) and the large cardinals in the subtle/$k$-SRP range.

An example of the sort of statement he considers is the following (from this document):

Definition 1. $S\subseteq\mathbb{Q}[0,n]^k$ is an emulator of $E\subseteq\mathbb{Q}[0,n]^k$ if each element of $S^2$ is order equivalent to some member of $E^2$ (considered as subsets of $\mathbb{Q}[0,n]^{2k}$), where $x,y\in\mathbb{Q}[0,n]^k$ are said to be order equivalent if for any $1\leq i,j\leq k$, $x_i<x_j\leftrightarrow y_i<y_j$.

Definition 2. $A\subseteq\mathbb{Q}[0,n]^k$ is stable if and only if for all $p<1$, $\langle p,1,\ldots,k-1\rangle\in A\leftrightarrow\langle p,2,\ldots,k\rangle\in A$.

Example statement (called "MES" by Friedman). For all $k$, and all finite $E\subseteq\mathbb{Q}[0,k]^k$, there is a stable, $\subseteq$-maximal emulator of $E$.

Apparently MES implies $\mathrm{Con}(\mathsf{SRP})$ (where $\mathsf{SRP}$ is $\mathsf{ZFC}$+"there is a $k$-SRP cardinal" as an axiom scheme in $k$), so somehow there is a lot of strength happening in stable maximal emulators. And the relation to $k$-SRP cardinals, specifically, makes me think that emulators must be hiding a Ramsey condition under the hood, but I haven't been able to spot it yet.

How can I see what is happening with stable maximal emulators of finite subsets of $\mathbb{Q}[0,n]^k$ ($n,k>2$) that their guaranteed existence implies the consistency of the existence of large cardinals? [Edited to reflect JDH's correction in the comments.]

(For a reference on $k$-SRP cardinals, see Friedman, Harvey. Subtle cardinals and linear orderings. (English summary) Ann. Pure Appl. Logic 107 (2001), no. 1-3, 1–34.)

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Seeing what gets Harvey Friedman's "tangible incompleteness" principles into large cardinal territory

I'm trying to wrap my head around some of Harvey Friedman's recent, unpublished work on his tangible incompleteness project, and I'm trying to see the link between his "tangible statements" (propositions about subsets of $\mathbb{Q}[0,n]^k:=\{x\in\mathbb{Q}\;|\;0\leq x\leq n\}^k$ for $n,k\in\mathbb{N}$) and the large cardinals in the subtle/$k$-SRP range.

An example of the sort of statement he considers is the following (from this document):

Definition 1. $S\subseteq\mathbb{Q}[0,n]^k$ is an emulator of $E\subseteq\mathbb{Q}[0,n]^k$ if each element of $S^2$ is order equivalent to some member of $E^2$ (considered as subsets of $\mathbb{Q}[0,n]^{2k}$), where $x,y\in\mathbb{Q}[0,n]^k$ are said to be order equivalent if for any $1\leq i,j\leq k$, $x_i<x_j\leftrightarrow y_i<y_j$.

Definition 2. $A\subseteq\mathbb{Q}[0,n]^k$ is stable if and only if for all $p<1$, $\langle p,1,\ldots,k-1\rangle\in A\leftrightarrow\langle p,2,\ldots,k\rangle\in A$.

Example statement (called "MES" by Friedman). For all $k$, and all finite $E\subseteq\mathbb{Q}[0,k]^k$, there is a stable, $\subseteq$-maximal emulator of $E$.

Apparently MES implies $\mathrm{Con}(\mathsf{SRP})$ (where $\mathsf{SRP}$ is $\mathsf{ZFC}$+"there is a $k$-SRP cardinal" as an axiom scheme in $k$), so somehow there is a lot of strength happening in stable maximal emulators. And the relation to $k$-SRP cardinals, specifically, makes me think that emulators must be hiding a Ramsey condition under the hood, but I haven't been able to spot it yet.

How can I see what is happening with stable maximal emulators of finite subsets of $\mathbb{Q}[0,n]^k$ ($n,k>2$) that their guaranteed existence implies the existence of large cardinals?

(For a reference on $k$-SRP cardinals, see Friedman, Harvey. Subtle cardinals and linear orderings. (English summary) Ann. Pure Appl. Logic 107 (2001), no. 1-3, 1–34.)