Learning the theory of Langlands correspondence, I met the notion of "special" maximal compact subgroup of a (reductive) algebraic group over a local field.

Here, I think the word "compact" is used in analytic meaning.

The textbook I used did not explain the definition of "special".

My questions:

(1) What is the definition of "special" maximal compact subgroup?

(2) Is there any concrete example of maximal compact subgroup which is NOT "special"?

Please give me any advise.

Learning the theory of Langlands correspondence, I met the notion of "special" maximal compact subgroup of a (reductive) algebraic group over a local field.

Here, I think the word "compact" is used in analytic meaning.

The textbook I used did not explain the definition of "special".

My questions:

(1) What is the definition of "special" maximal compact subgroup?

(2) Is there any concrete example of maximal compact subgroup which is NOT "special"?

Please give me any advice.

Learning the theory of Langlands correspondence, I met the notion of "special" maximal compact subgroup of a (reductive) algebraic group over a local field.

Here, I think the word "compact" is used in analytic meaning.

The textbook I used did not explain the definition of "special".

My questions are:

(1) What is the definition of "special" maximal compact subgroup?

(2) Is there any concrete example of maximal compact subgroup which is NOT "special"?

Please give me any advise.

Learning the theory of Langlands correspondence, I met the notion of "special" maximal compact subgroup of a (reductive) algebraic group over a local field.

Here, I think the word "compact" is used in analytic meaning.

The textbook I used did not explain the definition of "special".

My questions:

(1) What is the definition of "special" maximal compact subgroup?

(2) Is there any concrete example of maximal compact subgroup which is NOT "special"?

Please give me any advise.