David Blaschke, University of Wrocław, Poland
Gravitational wave observations of GW170817 placed bounds on the tidal deformabilities of compact stars allowing one to probe equations of state for matter at supranuclear densities. I report on recent new parameterizations for hybrid hadron-quark equations of state, tested against GW170817 [1-3]. It is found that GW170817 is consistent with the coalescence of a binary hybrid star-neutron star where the hybrid star can be a member of the hypothetical third family of compact stars which leads to the phenomenon of mass twins. I also comment on a curiosity  that shall not be taken seriously.
 V. Paschalidis et al., arxiv:1712.00451
 M. Kaltenborn et al., Phys. Rev. D 96 (2017)
 A. Ayriyan et al., arxiv:1711.03926
 E. Annala et al., arxiv:1711.06244