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Vague question is the following:

Is there a classifcation of Lie groupoids?

Slightly less vague question is the following:

Is there a (short?) list of "types" of Lie groupoids such that any arbitrary Lie groupoid is Morita equivalent to one from the list?

Some Lie groupoids I know are the following:

  1. Lie groupoids coming from manifolds $[M\rightrightarrows M]$,
  2. Lie groupoids coming from Lie group $[G\rightrightarrows *]$,
  3. Lie groupoids coming from action of a Lie group on a manifold $[G\times M\rightrightarrows M]$,
  4. Lie groupoids coming from foliation on a manifold $\mathcal{F}(M)$,
  5. Lie groupoids coming from a submersion, the submersion groupoid $[M\times_NM\rightrightarrows M]$
  6. Lie groupoids coming from a principal $G$-bundle, the Gauge groupoid,
  7. Lie groupoids coming from a vector bundle over $M$, the general linear Lie groupoid $[GL(E)\rightrightarrows M]$.

Do we know any "interesting" Lie groupoids that do not belong (not Morita equivalent) to the above list?

Only classification I know is if a Lie groupoid is proper and étale, then it is locally looks like action Lie groupoid.

I might have forgot one or two types, but these are the only types of Lie groupoids I have come across till now.

Edit: It turns out my question was not conveyed correctly. I do know that there is no hope of classifying Lie groups. I do not want to classify Lie groups. For me, all Lie groupoids that comes from Lie groups are of "same type". So, the classification I am looking for is only based on types. I think I conveyed it correctly now. If this is not clear, please do ask for more clarification.

Vague question is the following:

Is there a classifcation of Lie groupoids?

Slightly less vague question is the following:

Is there a (short?) list of "types" of Lie groupoids such that any arbitrary Lie groupoid is Morita equivalent to one from the list?

Some Lie groupoids I know are the following:

  1. Lie groupoids coming from manifolds $[M\rightrightarrows M]$,
  2. Lie groupoids coming from Lie group $[G\rightrightarrows *]$,
  3. Lie groupoids coming from action of a Lie group on a manifold $[G\times M\rightrightarrows M]$,
  4. Lie groupoids coming from foliation on a manifold $\mathcal{F}(M)$,
  5. Lie groupoids coming from a submersion, the submersion groupoid $[M\times_NM\rightrightarrows M]$
  6. Lie groupoids coming from a principal $G$-bundle, the Gauge groupoid,
  7. Lie groupoids coming from a vector bundle over $M$, the general linear Lie groupoid $[GL(E)\rightrightarrows M]$.

Do we know any "interesting" Lie groupoids that do not belong (not Morita equivalent) to the above list?

Only classification I know is if a Lie groupoid is proper and étale, then it is locally looks like action Lie groupoid.

I might have forgot one or two types, but these are the only types of Lie groupoids I have come across till now.

Vague question is the following:

Is there a classifcation of Lie groupoids?

Slightly less vague question is the following:

Is there a (short?) list of "types" of Lie groupoids such that any arbitrary Lie groupoid is Morita equivalent to one from the list?

Some Lie groupoids I know are the following:

  1. Lie groupoids coming from manifolds $[M\rightrightarrows M]$,
  2. Lie groupoids coming from Lie group $[G\rightrightarrows *]$,
  3. Lie groupoids coming from action of a Lie group on a manifold $[G\times M\rightrightarrows M]$,
  4. Lie groupoids coming from foliation on a manifold $\mathcal{F}(M)$,
  5. Lie groupoids coming from a submersion, the submersion groupoid $[M\times_NM\rightrightarrows M]$
  6. Lie groupoids coming from a principal $G$-bundle, the Gauge groupoid,
  7. Lie groupoids coming from a vector bundle over $M$, the general linear Lie groupoid $[GL(E)\rightrightarrows M]$.

Do we know any "interesting" Lie groupoids that do not belong (not Morita equivalent) to the above list?

Only classification I know is if a Lie groupoid is proper and étale, then it is locally looks like action Lie groupoid.

I might have forgot one or two types, but these are the only types of Lie groupoids I have come across till now.

Edit: It turns out my question was not conveyed correctly. I do know that there is no hope of classifying Lie groups. I do not want to classify Lie groups. For me, all Lie groupoids that comes from Lie groups are of "same type". So, the classification I am looking for is only based on types. I think I conveyed it correctly now. If this is not clear, please do ask for more clarification.

Source Link

Do we have classification (upto Morita equivalence) of Lie groupoids?

Vague question is the following:

Is there a classifcation of Lie groupoids?

Slightly less vague question is the following:

Is there a (short?) list of "types" of Lie groupoids such that any arbitrary Lie groupoid is Morita equivalent to one from the list?

Some Lie groupoids I know are the following:

  1. Lie groupoids coming from manifolds $[M\rightrightarrows M]$,
  2. Lie groupoids coming from Lie group $[G\rightrightarrows *]$,
  3. Lie groupoids coming from action of a Lie group on a manifold $[G\times M\rightrightarrows M]$,
  4. Lie groupoids coming from foliation on a manifold $\mathcal{F}(M)$,
  5. Lie groupoids coming from a submersion, the submersion groupoid $[M\times_NM\rightrightarrows M]$
  6. Lie groupoids coming from a principal $G$-bundle, the Gauge groupoid,
  7. Lie groupoids coming from a vector bundle over $M$, the general linear Lie groupoid $[GL(E)\rightrightarrows M]$.

Do we know any "interesting" Lie groupoids that do not belong (not Morita equivalent) to the above list?

Only classification I know is if a Lie groupoid is proper and étale, then it is locally looks like action Lie groupoid.

I might have forgot one or two types, but these are the only types of Lie groupoids I have come across till now.