Hello everybody, this question is mainly addressed to people interested or involved in superconductivity. In the paper "Is there a glue in cuprate superconductors?" (Link - 2007) Anderson argues that the most important element to understand the pairing mechanism in cuprates is the proximity of the superconducting state to the Mott phase. If I'm not wrong, this would mean that superconductivity arises due to the interaction with high-energy excitations in cuprates, determined by the charge-transfer gap of the undoped parent compound and the superexchange interaction. To your knowledge, are there any experimental observations confirming this point? By looking in the literature, it seems that people just take care of finding the mysterious bosonic glue that binds the Cooper pairs together... Thanks in advance for your answers!