Reacción a "Reactions: A study still pending review announces the first superconductor at room temperature and pressure"

The recent preprint by Lee, Kim and Kwon suggesting that they have observed room temperature superconductivity in the copper doped lead phosphate system, without the need for very high applied pressures, is interesting, but not yet wholly convincing.  The data presented showing a sharp drop in bulk resistivity suggests an abrupt phase transition around 100 oC, but whether this is a result of the formation of a superconducting state is not clear.  A similarly sharp transition in the magnetisation signal would be expected at the same temperature if a significant volume of the sample has become superconducting, as well as an anomaly in the specific heat capacity.  Neither of these features is evident in the data presented, and so it is too early to say that we have been presented with compelling evidence for superconductivity in these samples.  It will be interesting to see if other laboratories can repeat and improve on these preliminary observations.