Langa Dias, the name once caused an uproar in the physics community. His proclaimed discovery of "room-temperature superconductivity" has shocked the global scientific community, as if opening the door to a new world.
However, amid the constant skepticism of the scientific community, cracks are gradually being revealed. Dias's research papers on room-temperature superconductivity were twice retracted by Nature, and two other papers were also retracted by journals.
Recently, a 124-page court document cited by the Nature news team said that a 10-month-long investigation by the University of Rochester in the United States found that Dias had multiple misconduct such as falsifying experimental data and plagiarism.
Image source: Screenshot of the Nature article
The survey, conducted by an independent scientific team hired by the university, ended on February 8 this year. The scientific team reviewed 16 charges against Professor Dias and concluded that in each of the charges, Dias was likely guilty of academic misconduct.
Dias is a tenured faculty member at the University of Rochester, but the university is currently trying to fire him before his contract ends in the 2024~25 academic year, i.e., before August 31, 2025.
Mr. Dias did not respond to a request for comment, but his lawyer provided the Nature's team with documents from the lawsuit. In one of the documents, Díaz said that "in the midst of criticism and accusations, we must reaffirm the fundamental integrity and scientific nature of our work".
It has been investigated three times before
The result is "no end"
According to the latest report from the Nature news team, documents filed by the University of Rochester with the court show that the investigation against Dias was ordered by the National Science Foundation (NSF), a major funding agency for academic research in the United States, which awarded Dias a $790,000 CAREER grant in 2021. However, the NSF Inspector General's Office declined to comment on the findings or future actions of the agency.
In March last year, the Langa Dias research team at the University of Rochester in the United States announced that it had achieved "room-temperature superconductivity" that the global scientific community had pursued for many years. However, about eight months later, Nature announced that it was retracting the paper, which caused a global sensation, at the request of eight co-authors of the paper, because the researchers believed that the published paper did not accurately reflect the source of the material studied, the experimental methods used and the data processing basis applied.
This is the second time that Dias's team's research paper on room-temperature superconductivity has been retracted by Nature. In August of the same year, the American "Physical Review Letters" retracted the paper published in the journal in 2021 by Dias et al. due to "obvious data fraud".
The University of Rochester's 124-page report details Diaz's deception in the three retracted papers, as well as another in Chemical Letters. In two papers published in Nature, Dias first claimed to have discovered room-temperature superconductivity (i.e., zero resistance at ambient temperature) in a compound composed of carbon, sulfur and hydrogen (CSH), and then in a compound composed of lutetium and hydrogen (LuH).
The reporter of "Daily Economic News" noted that the investigation ordered by NSF is not the first time that the University of Rochester has launched an investigation into possible problems in the Dias laboratory.
During 2021~2022, the university conducted three preliminary "investigations" on the room-temperature superconductivity paper of CSH compounds published by the Dias team in the journal Nature. The first preliminary investigation was launched after Jorge Hirsch, a condensed matter theorist at the University of California, San Diego, filed a complaint with the University of Rochester. The university questioned three unnamed internal reviewers, and Dias contacted an external reviewer to review Hirsch's complaint. According to the investigative report, the external examiner was Maduri Somayazulu, a physicist at Argonne National Laboratory in Lemont, Illinois.
Image source: Survey report
Professor Hirsch's complaint alleges that there are problems with the magnetic induction intensity data in Dias's paper, which is key evidence for Dias to say CSH is a room-temperature superconductor. The investigation team concluded on January 19, 2022, that "there is no credible evidence to warrant further investigation".
The second investigation was initiated by Dirk van der Marel, editor-in-chief of the superconductivity research journal Physica C. On January 20, 2022, the day after the conclusion of the first survey, Vandermarel voiced concerns to the University of Rochester about the superconductivity data of CSH compounds. On April 6 of the same year, another reviewer took over the case and decided that no formal investigation was necessary. According to the identity information discussed in the report, the second examiner may be Russell Hemley, a physicist at the University of Illinois at Chicago. Although the reviewers did not support the investigation, they said the paper "omitted details and appeared misleading". They suggested errata (but it didn't).
The University of Rochester survey noted that two reviewers, Somayazulu and Heimli, collaborated with Dias on several papers, including a 2021 paper on the study of the room-temperature superconductivity properties of CSH. The University of Rochester's Academic Misconduct Policy states that "any individual who has an unresolved personal, professional, or financial conflict of interest...... shall not participate in the investigative process".
A spokesman for Agung denied that Somayazulu was a reviewer for the investigation, but did not answer when asked why the footnotes to the investigation mentioned "Somayazulu's report_review of the National Science Foundation (CSH) paper." Heimli did not clarify whether he was a survey reviewer.
The Nature team conducted an independent investigation of the CSH room-temperature superconductivity paper using independent reviewers, and two of the reviewers found evidence that the magnetic susceptibility data in the Dias paper may be fabricated. When Nature said it would retract Dias's CSH paper and responded to another complaint from Hirsch, the University of Rochester conducted a third investigation. Although the findings of Nature are available, the sole reviewer responsible for this survey, the anonymous reviewer for the second survey, concluded on October 19, 2022, that any oddities in the data could be attributed to how the data was handled, so there was no need for an investigation.
Investigators confirmed: Dias fabricated the data
It can be said that the previous three investigations were fruitless. The full investigation was eventually forced to be carried out at the behest of the NSF.
James Hamlin, a physicist at the University of Florida, submitted concerns about Dias's work to the NSF. According to a March 16, 2023 letter from NSF to Stephen Duchst, then interim vice chancellor for research at the University of Rochester, the issues included "data discrepancies that cannot be attributed to data processing."
Within weeks, Duhurst had convened a committee of three physicists from outside the university, Marius Millot and Peter Celliers of Lawrence Livermore National Laboratory in California, and Marcus Knudson of Sandia National Laboratory in Albuquerque, New Mexico, to "make sure the investigation was credible."
In the course of its work, the Commission of Inquiry obtained a variety of records, including data on computer hard drives, e-mails and notebooks. They also interviewed 10 people involved in the case, including Díaz and some of his former students, and met at least 50 times to discuss them. Notably, investigators corroborated Vandermarel, Hirsch, and Hamlin's previous analysis, all of which found clear evidence that Dias fabricated magnetic induction intensity data in the CSH paper.
According to the investigative report, Díaz first fabricated the CSH data and published it, and to make matters worse, when the source of the data came under scrutiny, Díaz and his collaborator, Ashkan Salamat, a physicist at the University of Nevada in Las Vegas, also published a set of fabricated raw data.
When the discrepancy between the raw and published data is increasingly questioned, Dias offers an explanation that he says a well-designed approach to data processing is used for the published data. This provides "a veneer of plausibility that focuses the attention of critics on its methods" rather than raw data, the commission of inquiry wrote.
In fact, if Díaz had provided authentic raw data, i.e., data taken directly from the measuring instrument, with details such as time stamps, he could have dispelled many of the accusations. In response to the findings, Díaz also wrote: "The absence of certain raw data files does not mean that they do not exist, nor does it mean that I have any wrongdoing." ”
However, despite several promises to provide raw data, he never did.
Similarity between two different resistance diagrams extracted from Ranga Dias's paper. Image source: Nature
Commission of Inquiry finds: "Díaz is not credible"
The investigation found that in some cases, Dias also misled team members and collaborators about the information from the data sources. In interviews, investigators found that Dias told his partners at the University of California, Los Angeles (UCLA) that the measurements were taken at the University of Rochester, however, speaking to researchers at the University of Rochester, said the measurements were taken at UCLA.
On December 22, 2023, the Commission of Inquiry sent a draft report to Dias. In the 124-page document, Dias gave a two-part response in which he slammed the investigators' expertise and integrity issues. Dias said the investigators' methods showed "characteristics that can sometimes be seen in the field of conspiracy theories" and "lacked a strong logical basis."
Mr. Díaz also said that Mr. Salamat persuaded Mr. Dias's former students to oppose him because they had sent a letter to Nature demanding the retraction of LuH's paper on room-temperature superconductivity. But the opposite is true: Nature's team previously reported that it was his students who sent the letter to Nature.
In his response, Díaz did not provide the original data requested by the committee. In the final report, the investigators responded to Dias's accusations, saying that "the citation of 'baroque' explanations to illustrate and therefore justify the omission of these data does not alter the reasoning or conclusions of the commission of inquiry".
Ultimately, the commission of inquiry concluded that the University of Rochester student and Dissanayake were not the culprits, but the victims. The committee did not have access to the resources of the University of Nevada, Las Vegas, to clear the name of the researchers, including Salamat, but found that they were also deceived and found no "substantial evidence of misconduct."
The investigative report summarizes years of allegations and analysis, systematically documenting how Díaz deliberately misled his co-authors, journal editors, and the scientific community. The investigation team believes that in all 16 charges against Dias, he is likely to have committed academic misconduct. A spokesperson for the University of Rochester called the investigation "an unbiased and thorough process" and came to the right conclusions.
As a result, the investigators recommend terminating Dias' teaching credentials or engaging in publicly or privately funded research. They added: "The evidence found in this investigation suggests that Dias cannot be trusted. ”
Mr. Dias did not respond to Nature's request for comment, but his lawyer provided the Nature's team with documents from the lawsuit. In one of the documents, Díaz said that "in the midst of criticism and accusations, we must reaffirm the fundamental integrity and scientific nature of our work".
Source: National Business Daily