Group-like projections for locally compact quantum groups

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Let G be a locally compact quantum group. We give a 1-1 correspondence between group-like projections in L∞(G) preserved by the scaling group and idempotent states on the dual quantum group G. As a byproduct we give a simple proof that normal integrable coideals in L∞(G) which are preserved by the scaling group are in 1-1 correspondence with compact quantum subgroups of G.