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discretifications Discretifications of the fundamental group functor  

Grothendieck calls a "discretification" of a profinite group $\hat G$$\widehat G$, a discrete group $G$ whose profinite completion is isomorphic to $\hat G$$\widehat G$.

Does Grothendieck also define a notion of the "discretification" of a functor to profinite groups, and particulary that of the algebraic fundamental group functor?

The automorphisms of the geometric point act on the discretifications of the fundamental group functor; and thus one can ask:

are all discretifications of the the algebraic fundamental group functor related by automorphisms of the geometric point? To simplify the question, one may abelianise the functor and/or restrict it to a full subcategory of schemes $X\longrightarrow S$, $S=Spec k$$S=\mathrm{Spec}\ k$ a number field or $k=K$.

Here is the same question with some more notation and detail. Please excuse my poor notation: I am not very familiar with the language of schemes.

Say a functor F$F$ to finitely generated Abelian groups is a discretification of a functor F'$F'$ to profinite groups iff for every $X$, $F(X)$ is a discretification of $F'(X)$. Equivalently, one is given an equivalence $\hat F==>F'$$\widehat F \Rightarrow F'$ (where $\hat F(X)=\hat{F(X)}$$\widehat F(X)=\widehat{F(X)}$ is the profinite completion of $F(X)$.)

The algebraic fundamental group is, or at least defines, a functor $pi_1^{alg}:$ Spec K\Schemes $\longrightarrow ProfiniteGroups$ from$\pi_1^{alg}: \mathrm{Spec}\ K\text{\Schemes} \longrightarrow \text{ProfiniteGroups}$ from the category Spec K\Schemes $= Mor (Spec K, Schemes)$ of$\mathrm{Spec}\ K\text{\Schemes}= \mathrm{Mor} (\mathrm{Spec}\ K, \text{\Schemes})$ of Schemes cosliced over a geometric point $Spec K$$\mathrm{Spec}\ K$.

There is a canonical Aut(K/Q)$\mathrm{Aut}(K/\mathbb{Q})$ action on Spec K\Schemes which$\mathrm{Spec}\ K\text{\Schemes}$ which extends to an action on the discretifications of of this functor. Did Grothendicek conjecture anything anything about this action?

Is there a better way to state this question? E.g. using using the fact that for K the field of algebraic numbers $Aut(K/Q)=pi_1^{alg}(Spec Q, SpecK)$ $\mathrm{Aut}(K/\mathbb{Q})=\pi_1^{alg}(\mathrm{Spec}\ \mathbb{Q}, \mathrm{Spec}\ K)$.

One can modify the question by replacing the category of of Schemes by a subcategory of Schemes over Spec k or$\mathrm{Spec}\ k$ or some other scheme, and then considering double cosets cosets of Aut(K/Q)$\mathrm{Aut}(K/\mathbb{Q})$ and Aut(k/Q)$\mathrm{Aut}(k/\mathbb{Q})$ action; as an example, one one may consider the full subcategory of etale covers of of direct products of moduli spaces of curves....

Perhaps I should also add that probably I can prove some some very partial positive results, for some very small and and "abelian" subcategories of Schemes. That's the motivation for the question.

discretifications of the fundamental group functor  

Grothendieck calls a "discretification" of a profinite group $\hat G$, a discrete group $G$ whose profinite completion is isomorphic to $\hat G$.

Does Grothendieck also define a notion of the "discretification" of a functor to profinite groups, and particulary that of the algebraic fundamental group functor?

The automorphisms of the geometric point act on the discretifications of the fundamental group functor; and thus one can ask:

are all discretifications of the the algebraic fundamental group functor related by automorphisms of the geometric point? To simplify the question, one may abelianise the functor and/or restrict it to a full subcategory of schemes $X\longrightarrow S$, $S=Spec k$ a number field or $k=K$.

Here is the same question with some more notation and detail. Please excuse my poor notation: I am not very familiar with the language of schemes.

Say a functor F to finitely generated Abelian groups is a discretification of a functor F' to profinite groups iff for every $X$, $F(X)$ is a discretification of $F'(X)$. Equivalently, one is given an equivalence $\hat F==>F'$ (where $\hat F(X)=\hat{F(X)}$ is the profinite completion of $F(X)$.)

The algebraic fundamental group is, or at least defines, a functor $pi_1^{alg}:$ Spec K\Schemes $\longrightarrow ProfiniteGroups$ from the category Spec K\Schemes $= Mor (Spec K, Schemes)$ of Schemes cosliced over a geometric point $Spec K$.

There is a canonical Aut(K/Q) action on Spec K\Schemes which extends to an action on the discretifications of this functor. Did Grothendicek conjecture anything about this action?

Is there a better way to state this question? E.g. using the fact that for K the field of algebraic numbers $Aut(K/Q)=pi_1^{alg}(Spec Q, SpecK)$.

One can modify the question by replacing the category of Schemes by a subcategory of Schemes over Spec k or some other scheme, and then considering double cosets of Aut(K/Q) and Aut(k/Q) action; as an example, one may consider the full subcategory of etale covers of direct products of moduli spaces of curves....

Perhaps I should also add that probably I can prove some very partial positive results, for some very small and "abelian" subcategories of Schemes. That's the motivation for the question.

Discretifications of the fundamental group functor

Grothendieck calls a "discretification" of a profinite group $\widehat G$, a discrete group $G$ whose profinite completion is isomorphic to $\widehat G$.

Does Grothendieck also define a notion of the "discretification" of a functor to profinite groups, and particulary that of the algebraic fundamental group functor?

The automorphisms of the geometric point act on the discretifications of the fundamental group functor; and thus one can ask:

are all discretifications of the the algebraic fundamental group functor related by automorphisms of the geometric point? To simplify the question, one may abelianise the functor and/or restrict it to a full subcategory of schemes $X\longrightarrow S$, $S=\mathrm{Spec}\ k$ a number field or $k=K$.

Here is the same question with some more notation and detail. Please excuse my poor notation: I am not very familiar with the language of schemes.

Say a functor $F$ to finitely generated Abelian groups is a discretification of a functor $F'$ to profinite groups iff for every $X$, $F(X)$ is a discretification of $F'(X)$. Equivalently, one is given an equivalence $\widehat F \Rightarrow F'$ (where $\widehat F(X)=\widehat{F(X)}$ is the profinite completion of $F(X)$.)

The algebraic fundamental group is, or at least defines, a functor $\pi_1^{alg}: \mathrm{Spec}\ K\text{\Schemes} \longrightarrow \text{ProfiniteGroups}$ from the category $\mathrm{Spec}\ K\text{\Schemes}= \mathrm{Mor} (\mathrm{Spec}\ K, \text{\Schemes})$ of Schemes cosliced over a geometric point $\mathrm{Spec}\ K$.

There is a canonical $\mathrm{Aut}(K/\mathbb{Q})$ action on $\mathrm{Spec}\ K\text{\Schemes}$ which extends to an action on the discretifications of this functor. Did Grothendicek conjecture anything about this action?

Is there a better way to state this question? E.g. using the fact that for K the field of algebraic numbers $\mathrm{Aut}(K/\mathbb{Q})=\pi_1^{alg}(\mathrm{Spec}\ \mathbb{Q}, \mathrm{Spec}\ K)$.

One can modify the question by replacing the category of Schemes by a subcategory of Schemes over $\mathrm{Spec}\ k$ or some other scheme, and then considering double cosets of $\mathrm{Aut}(K/\mathbb{Q})$ and $\mathrm{Aut}(k/\mathbb{Q})$ action; as an example, one may consider the full subcategory of etale covers of direct products of moduli spaces of curves....

Perhaps I should also add that probably I can prove some very partial positive results, for some very small and "abelian" subcategories of Schemes. That's the motivation for the question.

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Grothendieck calls a "discretification" of a profinite group $\hat G$, a discrete group $G$ whose profinite completion is isomorphic to $\hat G$.

Does Grothendieck also define a notion of the "discretification" of a functor to profinite groups, and particulary that of the algebraic fundamental group functor?

The automorphisms of the geometric point act on the discretifications of the fundamental group functor; and thus one can ask:

are all discretifications of the the algebraic fundamental group functor related by automorphisms of the geometric point? To simplify the question, one may abelianise the functor and/or restrict it to a full subcategory of schemes $X\longrightarrow S$, $S=Spec k$ a number field or $k=K$.

Here is the same question with some more notation and detail. Please excuse my poor notation: I am not very familiar with the language of schemes.

Say a functor F to finitely generated Abelian groups is a discretification of a functor F' to profinite groups iff for every $X$, $F(X)$ is a discretification of $F'(X)$. Equivalently, one is given an equivalence $\hat F==>F'$ (where $\hat F(X)=\hat{F(X)}$ is the profinite completion of $F(X)$.)

The algebraic fundamental group is, or at least defines, a functor $pi_1^{alg}:$ Spec K\Schemes $\longrightarrow ProfiniteGroups$ from the category Spec K\Schemes $= Mor (Spec K, Schemes)$ of Schemes cosliced over a geometric point $Spec K$.

There is a canonical Aut(K/Q) action on Spec K\Schemes which extends to an action on the discretifications of this functor. Did Grothendicek conjecture anything about this action?

Is there a better way to state this question? E.g. using the fact that for K the field of algebraic numbers $Aut(K/Q)=pi_1^{alg}(Spec Q, SpecK)$.

One can modify the question by replacing the category of Schemes by a subcategory of Schemes over Spec k or some other scheme, and then considering double cosets of Aut(K/Q) and Aut(k/Q) action; as an example, one may consider the full subcategory of etale covers of direct products of moduli spaces of curves....

Perhaps I should also add that probably I can prove some very partial positive results, for some very small and "abelian" subcategories of Schemes. That's the motivation for the question.

Grothendieck calls a "discretification" of a profinite group $\hat G$, a discrete group $G$ whose profinite completion is isomorphic to $\hat G$.

Does Grothendieck also define a notion of the "discretification" of a functor to profinite groups, and particulary that of the algebraic fundamental group functor?

The automorphisms of the geometric point act on the discretifications of the fundamental group functor; and thus one can ask:

are all discretifications of the the algebraic fundamental group functor related by automorphisms of the geometric point? To simplify the question, one may abelianise the functor and/or restrict it to a full subcategory of schemes $X\longrightarrow S$, $S=Spec k$ a number field or $k=K$.

Here is the same question with some more notation and detail. Please excuse my poor notation: I am not very familiar with the language of schemes.

Say a functor F to finitely generated Abelian groups is a discretification of a functor F' to profinite groups iff for every $X$, $F(X)$ is a discretification of $F'(X)$. Equivalently, one is given an equivalence $\hat F==>F'$ (where $\hat F(X)=\hat{F(X)}$ is the profinite completion of $F(X)$.)

The algebraic fundamental group is, or at least defines, a functor $pi_1^{alg}:$ Spec K\Schemes $\longrightarrow ProfiniteGroups$ from the category Spec K\Schemes $= Mor (Spec K, Schemes)$ of Schemes cosliced over a geometric point $Spec K$.

There is a canonical Aut(K/Q) action on Spec K\Schemes which extends to an action on the discretifications of this functor. Did Grothendicek conjecture anything about this action?

Is there a better way to state this question? E.g. using the fact that for K the field of algebraic numbers $Aut(K/Q)=pi_1^{alg}(Spec Q, SpecK)$.

One can modify the question by replacing the category of Schemes by a subcategory of Schemes over Spec k or some other scheme, and then considering double cosets of Aut(K/Q) and Aut(k/Q) action; as an example, one may consider the full subcategory of etale covers of direct products of moduli spaces of curves....

Grothendieck calls a "discretification" of a profinite group $\hat G$, a discrete group $G$ whose profinite completion is isomorphic to $\hat G$.

Does Grothendieck also define a notion of the "discretification" of a functor to profinite groups, and particulary that of the algebraic fundamental group functor?

The automorphisms of the geometric point act on the discretifications of the fundamental group functor; and thus one can ask:

are all discretifications of the the algebraic fundamental group functor related by automorphisms of the geometric point? To simplify the question, one may abelianise the functor and/or restrict it to a full subcategory of schemes $X\longrightarrow S$, $S=Spec k$ a number field or $k=K$.

Here is the same question with some more notation and detail. Please excuse my poor notation: I am not very familiar with the language of schemes.

Say a functor F to finitely generated Abelian groups is a discretification of a functor F' to profinite groups iff for every $X$, $F(X)$ is a discretification of $F'(X)$. Equivalently, one is given an equivalence $\hat F==>F'$ (where $\hat F(X)=\hat{F(X)}$ is the profinite completion of $F(X)$.)

The algebraic fundamental group is, or at least defines, a functor $pi_1^{alg}:$ Spec K\Schemes $\longrightarrow ProfiniteGroups$ from the category Spec K\Schemes $= Mor (Spec K, Schemes)$ of Schemes cosliced over a geometric point $Spec K$.

There is a canonical Aut(K/Q) action on Spec K\Schemes which extends to an action on the discretifications of this functor. Did Grothendicek conjecture anything about this action?

Is there a better way to state this question? E.g. using the fact that for K the field of algebraic numbers $Aut(K/Q)=pi_1^{alg}(Spec Q, SpecK)$.

One can modify the question by replacing the category of Schemes by a subcategory of Schemes over Spec k or some other scheme, and then considering double cosets of Aut(K/Q) and Aut(k/Q) action; as an example, one may consider the full subcategory of etale covers of direct products of moduli spaces of curves....

Perhaps I should also add that probably I can prove some very partial positive results, for some very small and "abelian" subcategories of Schemes. That's the motivation for the question.

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Grothendieck calls a "discretification" of a profinite group $\hat G$, a discrete group $G$ whose profinite completion is isomorphic to $\hat G$.

Does Grothendieck also define a notion of the "discretification" of a functor to profinite groups, and particulary that of the algebraic fundamental group functor?

The automorphisms of the geometric point act on the discretifications of the fundamental group functor; and thus one can ask:

are all discretifications of the the algebraic fundamental group functor related by automorphisms of the geometric point? To simplify the question, one may abelianise the functor and/or restrict it to a full subcategory of schemes $X\longrightarrow S$, $S=Spec k$ a number field or $k=K$.

Here is the same question with some more notation and detail. Please excuse my poor notation: I am not very familiar with the language of schemes.

Say a functor F to finitely generated Abelian groups is a discretification of a functor F' to profinite groups iff for every $X$, $F(X)$ is a discretification of $F'(X)$. Equivalently, one is given an equivalence $\hat F==>F'$ (where $\hat F(X)=\hat{F(X)}$ is the profinite completion of $F(X)$.)

The algebraic fundamental group is, or at least defines, a functor $pi_1^{alg}:$ Spec K\Schemes $\longrightarrow ProfiniteGroups$ from the category Spec K\Schemes $= Mor (Spec K, Schemes)$ of Schemes cosliced over a geometric point $Spec K$.

There is a canonical Aut(K/Q) action on Spec K\Schemes which extends to an action on the discretifications of this functor. Did Grothendicek conjecture anything about this action?

Is there a better way to state this question? E.g. using the fact that for K the field of algebraic numbers $Aut(K/Q)=pi_1^{alg}(Spec Q, SpecK)$.

One can modify the question by replacing the category of Schemes by a subcategory of Schemes over Spec k or some other scheme, and then considering double cosets of Aut(K/Q) and Aut(k/Q) action; as an example, one may consider the full subcategory of etale covers of direct products of moduli spaces of curves....

Grothendieck calls a "discretification" of a profinite group $\hat G$, a discrete group $G$ whose profinite completion is isomorphic to $\hat G$.

Does Grothendieck also define a notion of the "discretification" of a functor to profinite groups, and particulary that of the algebraic fundamental group functor?

The automorphisms of the geometric point act on the discretifications of the fundamental group functor; and thus one can ask:

are all discretifications of the the algebraic fundamental group functor related by automorphisms of the geometric point? To simplify the question, one may abelianise the functor and/or restrict it to a full subcategory of schemes $X\longrightarrow S$, $S=Spec k$ a number field.

Here is the same question with some more notation and detail. Please excuse my poor notation: I am not very familiar with the language of schemes.

Say a functor F to finitely generated Abelian groups is a discretification of a functor F' to profinite groups iff for every $X$, $F(X)$ is a discretification of $F'(X)$. Equivalently, one is given an equivalence $\hat F==>F'$ (where $\hat F(X)=\hat{F(X)}$ is the profinite completion of $F(X)$.)

The algebraic fundamental group is, or at least defines, a functor $pi_1^{alg}:$ Spec K\Schemes $\longrightarrow ProfiniteGroups$ from the category Spec K\Schemes $= Mor (Spec K, Schemes)$ of Schemes cosliced over a geometric point $Spec K$.

There is a canonical Aut(K/Q) action on Spec K\Schemes which extends to an action on the discretifications of this functor. Did Grothendicek conjecture anything about this action?

Is there a better way to state this question? E.g. using the fact that for K the field of algebraic numbers $Aut(K/Q)=pi_1^{alg}(Spec Q, SpecK)$.

One can modify the question by replacing the category of Schemes by a subcategory of Schemes over Spec k or some other scheme, and then considering double cosets of Aut(K/Q) and Aut(k/Q) action; as an example, one may consider the full subcategory of etale covers of direct products of moduli spaces of curves....

Grothendieck calls a "discretification" of a profinite group $\hat G$, a discrete group $G$ whose profinite completion is isomorphic to $\hat G$.

Does Grothendieck also define a notion of the "discretification" of a functor to profinite groups, and particulary that of the algebraic fundamental group functor?

The automorphisms of the geometric point act on the discretifications of the fundamental group functor; and thus one can ask:

are all discretifications of the the algebraic fundamental group functor related by automorphisms of the geometric point? To simplify the question, one may abelianise the functor and/or restrict it to a full subcategory of schemes $X\longrightarrow S$, $S=Spec k$ a number field or $k=K$.

Here is the same question with some more notation and detail. Please excuse my poor notation: I am not very familiar with the language of schemes.

Say a functor F to finitely generated Abelian groups is a discretification of a functor F' to profinite groups iff for every $X$, $F(X)$ is a discretification of $F'(X)$. Equivalently, one is given an equivalence $\hat F==>F'$ (where $\hat F(X)=\hat{F(X)}$ is the profinite completion of $F(X)$.)

The algebraic fundamental group is, or at least defines, a functor $pi_1^{alg}:$ Spec K\Schemes $\longrightarrow ProfiniteGroups$ from the category Spec K\Schemes $= Mor (Spec K, Schemes)$ of Schemes cosliced over a geometric point $Spec K$.

There is a canonical Aut(K/Q) action on Spec K\Schemes which extends to an action on the discretifications of this functor. Did Grothendicek conjecture anything about this action?

Is there a better way to state this question? E.g. using the fact that for K the field of algebraic numbers $Aut(K/Q)=pi_1^{alg}(Spec Q, SpecK)$.

One can modify the question by replacing the category of Schemes by a subcategory of Schemes over Spec k or some other scheme, and then considering double cosets of Aut(K/Q) and Aut(k/Q) action; as an example, one may consider the full subcategory of etale covers of direct products of moduli spaces of curves....

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