LK99

51% chance. Preprint here: https://arxiv.org/abs/2307.12008 Companion paper here with description of synthesis: https://arxiv.org/abs/2307.12037 Update 2023-07-27: Pasting my comment on resultion criteria We're clearly all here because a) it's fun, and b) we're interested in room temperature superconductivity, not whether some other experimental group gets the same kinda sus data as the original paper. So, when I write 'replicate' in the question I am specifically asking: is the room temperature, ambient pressure superconductivity of the compound LK-99 convincingly demonstrated? Specifically, replications should convincingly demonstrate: Zero DC electrical resistivity (or something close enough if the measurement is AC). A phase change*, which is usually exhibited as a sharp discontinuity in the heat capacity. The Meissner effect (magnetic fields expelled). If synthesizing the compound, there should be evidence that they did make something essentially the same as what is reported in the original paper. 2) has an asterisk because @BenjaminShindel suggests that a phase change might not be required for a quantum well superconductor. I think I see how this could be the case. Willing to adjust this criterion after receiving more info from relevant theorists/experimentalists. I don't intend to require that replications be published in a peer-reviewed journal. The arXiv is sufficient for me. However, I do intend to wait a few weeks/months to resolve so that any pre-print can be adequately investigated for data manipulation, fraud, etc. In my utopia, labs that claim to have confirmed/disconfirmed this effect would also publish their raw data with their arXiv submissions, but I'm not holding my breath. Since high Tc superconductivity is not my specific field of expertise, I'm willing to defer to a consensus of subject matter experts on whether a pre-print is convincing or not, and I am willing to contact some beyond the usual twitter personalities.