Acyclic compact Lie groups of dimension 3

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Are there any examples of compact connected Lie groups with vanishing first homology groups in dimension $3$ different from $S^3$?

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$S^3$ isn't acyclic, if by acyclic you mean having vanishing homology in positive degree; in fact no compact Lie group of positive dimension is acyclic, because they're closed and orientable and hence have nontrivial top homology.

The complete list of $3$-dimensional compact connected Lie groups is

  • $T^3$
  • $SU(2) \cong S^3$
  • $SO(3) \cong \mathbb{RP}^3$.

There are lots more disconnected ones, e.g. any of these times a finite group. Of these, $SU(2)$ is the only one that's simply connected. Is that what you meant?