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Let $G$ be a compact second countable Hausdorff group, and let $X=G/H$ be a homogeneous space with $H\subset G$ a closed subgroup. Let further $K\subset G$ be another closed subgroup.

Questions:

  1. Does there exist a section $s:K\backslash X\to X$ from the orbit space (double coset space) $K\backslash X=K\backslash G/H$ to the homogeneous space $X$ ( i.e., $Ks(Kx)=Kx$ for all $x\in X$ ) which is continuous aside from at most countably many orbits $Kx$?

  2. How does the answer to Questoin 1 change if I assume that $G$ is Lie?

Comment:

Even if $G$ is Lie, $X\to K\backslash X$ is not really a geometrical fibre bundle, since not all fibres ($K$-orbits) are isomorphic.

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  • $\begingroup$ What is the definition of your $K\setminus X$? I suspect that this is not a set-theoretic difference. Then what? $\endgroup$ – Taras Banakh May 19 '18 at 17:48
  • $\begingroup$ $K\backslash X$ (as opposed to the set difference $K\setminus X$) stands here for the set of left $K$-orbits. More precisely, $K\backslash X=K\backslash G/H$ is the double coset space, as it is written in the first question above. $\endgroup$ – Bedovlat Jun 6 '18 at 15:55

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