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add note about "spectral rings"
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dgulotta
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As mentioned by Scholze in this lecture (around 40:0000; uniform Tate rings are called "spectral rings" in the lecture), given given a directed system of maps of uniform Tate-Huber pairs $(R_i,R_i^+) \to (S,S^+)$, the map $\varinjlim_i R_i \to S$ is continuous for the $\varpi$-adic topology on $\varinjlim_i R_i^+$, where $\varpi$ is the image of a pseudouniformizer of some $R_i$. Here we need to use the fact that $S$ is uniform, so $S^+$ is a ring of definition and it has the $\varpi$-adic topology.

So filtered inverse limits should exist in the category of (sous)perfectoid spaces since (sous)perfectoid rings are stably uniform. Unfortunately I do not know of a reference that explicitly proves this, but it does seem to be used implicitly in Etale cohomolgy of diamonds.

As mentioned by Scholze in this lecture (around 40:00), given a directed system of maps of uniform Tate-Huber pairs $(R_i,R_i^+) \to (S,S^+)$, the map $\varinjlim_i R_i \to S$ is continuous for the $\varpi$-adic topology on $\varinjlim_i R_i^+$, where $\varpi$ is the image of a pseudouniformizer of some $R_i$. Here we need to use the fact that $S$ is uniform, so $S^+$ is a ring of definition and it has the $\varpi$-adic topology.

So filtered inverse limits should exist in the category of (sous)perfectoid spaces since (sous)perfectoid rings are stably uniform. Unfortunately I do not know of a reference that explicitly proves this, but it does seem to be used implicitly in Etale cohomolgy of diamonds.

As mentioned by Scholze in this lecture (around 40:00; uniform Tate rings are called "spectral rings" in the lecture), given a directed system of maps of uniform Tate-Huber pairs $(R_i,R_i^+) \to (S,S^+)$, the map $\varinjlim_i R_i \to S$ is continuous for the $\varpi$-adic topology on $\varinjlim_i R_i^+$, where $\varpi$ is the image of a pseudouniformizer of some $R_i$. Here we need to use the fact that $S$ is uniform, so $S^+$ is a ring of definition and it has the $\varpi$-adic topology.

So filtered inverse limits should exist in the category of (sous)perfectoid spaces since (sous)perfectoid rings are stably uniform. Unfortunately I do not know of a reference that explicitly proves this, but it does seem to be used implicitly in Etale cohomolgy of diamonds.

explained why the \varpi-adic topology is the correct one
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dgulotta
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As mentioned by Scholze mentions in this lecture (around 40:00) that there is, given a canonical waydirected system of defining a topology on a limitmaps of uniform Tate-Huber pairs (uniform Tate rings are called "spectral rings" in the lecture): give$(R_i,R_i^+) \to (S,S^+)$, the ring of integral elementsmap $R^+$$\varinjlim_i R_i \to S$ is continuous for the $\varpi$-adic topology on $\varinjlim_i R_i^+$, where $\varpi$ is the image of a pseudouniformizer of some $R_i$. Here we need to use the fact that $S$ is uniform, so $S^+$ is a ring of definition and it has the $\varpi$-adic topology.

So filtered inverse limits should exist in the category of perfectoid spaces (as well as in the category of sousperfectoid spacessous)perfectoid spaces since (sous)perfectoid rings are stably uniform. Unfortunately I do not know of a reference that explicitly proves this, but it does seem to be used implicitly in Etale cohomolgy of diamonds.

Scholze mentions in this lecture (around 40:00) that there is a canonical way of defining a topology on a limit of uniform Tate-Huber pairs (uniform Tate rings are called "spectral rings" in the lecture): give the ring of integral elements $R^+$ the $\varpi$-adic topology, where $\varpi$ is a pseudouniformizer.

So inverse limits should exist in the category of perfectoid spaces (as well as in the category of sousperfectoid spaces) since (sous)perfectoid rings are stably uniform. Unfortunately I do not know of a reference that explicitly proves this, but it does seem to be used implicitly in Etale cohomolgy of diamonds.

As mentioned by Scholze in this lecture (around 40:00), given a directed system of maps of uniform Tate-Huber pairs $(R_i,R_i^+) \to (S,S^+)$, the map $\varinjlim_i R_i \to S$ is continuous for the $\varpi$-adic topology on $\varinjlim_i R_i^+$, where $\varpi$ is the image of a pseudouniformizer of some $R_i$. Here we need to use the fact that $S$ is uniform, so $S^+$ is a ring of definition and it has the $\varpi$-adic topology.

So filtered inverse limits should exist in the category of (sous)perfectoid spaces since (sous)perfectoid rings are stably uniform. Unfortunately I do not know of a reference that explicitly proves this, but it does seem to be used implicitly in Etale cohomolgy of diamonds.

Source Link
dgulotta
  • 913
  • 1
  • 6
  • 13

Scholze mentions in this lecture (around 40:00) that there is a canonical way of defining a topology on a limit of uniform Tate-Huber pairs (uniform Tate rings are called "spectral rings" in the lecture): give the ring of integral elements $R^+$ the $\varpi$-adic topology, where $\varpi$ is a pseudouniformizer.

So inverse limits should exist in the category of perfectoid spaces (as well as in the category of sousperfectoid spaces) since (sous)perfectoid rings are stably uniform. Unfortunately I do not know of a reference that explicitly proves this, but it does seem to be used implicitly in Etale cohomolgy of diamonds.