Abstract
The configuration space of four points on the standard CR 3-sphere up to CR-automorphisms is a real four dimensional variety. We prove the existence of natural complex and CR structures on this space.
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I. D. Platis was supported by a Marie Curie Reintegration Grant fellowship (contract no. MEIF-CT-2005-028371) within the 6th Community Framework Programme.
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Falbel, E., Platis, I.D. The PU(2,1) configuration space of four points in S 3 and the cross-ratio variety. Math. Ann. 340, 935–962 (2008). https://doi.org/10.1007/s00208-007-0177-0
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DOI: https://doi.org/10.1007/s00208-007-0177-0