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An answer identifies the transition type and, if one exists, the order parameter whose fluctuations give the log divergence.","problem_ref":null,"references":"","settled_by":"Detection of the order parameter (or proof of its absence) by a symmetry-sensitive probe in the same high-field regime where C/T diverges.","status_note":"High-field specific heat (2019) found $C/T \\sim \\log(1/T)$ at $p*$ in Nd- and Eu-substituted La2-xSrxCuO4, but the associated order parameter is unidentified.","title":"Is the pseudogap endpoint p* a quantum critical 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