Why two 1940s papers by Nobel physicist Max Planck were withdrawn

German physicist Max Planck, celebrated as a founding figure of quantum mechanics and recipient of the 1918 Nobel Prize in Physics, has long stood as a paragon of scientific integrity. Yet a discovery by two science historians has cast an unexpected shadow over two of his lesser-known papers from the 1940s—papers that have now been withdrawn from a leading journal without clear explanation.

The journal Naturwissenschaften, now published as The Science of Nature, once hosted a digital archive where retracted papers were preserved with visible "RETRACTED" stamps. However, the two Planck papers from the 1940s have been removed entirely. Visitors to their URLs now encounter blank pages and empty PDFs, accompanied only by a brief note stating that the articles were "withdrawn due to article violation."

Physics historian Yves Gingras of the University of Quebec in Montreal first noticed Planck’s name on a Retraction Watch compilation of Nobel laureates whose papers had been retracted. Intrigued by the absence of any prior controversy around Planck, Gingras teamed up with Mahdi Khelfaoui of the University of Quebec at Trois-Rivières to investigate. Their findings were detailed in a preprint published on arXiv.

How the retraction came to light

The duo’s investigation began with a routine search. Gingras, while browsing Retraction Watch—a database that tracks scientific retractions—spotted Planck’s name among Nobel Prize winners with retracted papers. Given Planck’s unblemished reputation and the rarity of retractions involving Nobel laureates, the discovery warranted deeper inquiry.

The historians traced the retractions to Naturwissenschaften, a long-standing German journal that once served as a key venue for publishing groundbreaking physics research. While retracted papers are typically retained with prominent notices, the two Planck papers were not just flagged—they were erased from public view. The journal’s website now displays only a placeholder page and empty files, with minimal context about the withdrawal.

What constitutes an "article violation"?

The vague phrase "article violation" offers little clarity. Retraction Watch defines such violations as breaches of ethical standards, including plagiarism, data fabrication, or undisclosed conflicts of interest. However, the retraction notice provides no specifics about the nature of the violation or the timeline of the decision.

Gingras and Khelfaoui argue that the lack of transparency raises concerns about archival practices. When papers are withdrawn without explanation, it becomes difficult for historians, researchers, and the public to assess the integrity of the scientific record. The erasure of these documents also limits opportunities to study Planck’s later work, which remains under-examined despite his monumental early contributions.

Questions about scientific record-keeping persist

The case of Planck’s withdrawn papers underscores broader challenges in scientific publishing, particularly around transparency and archival access. Journals have historically varied in how they handle retractions—some preserve the original documents with clear flags, while others remove them entirely. The decision to erase rather than archive can obscure historical inquiry and hinder reproducibility.

For historians like Gingras and Khelfaoui, such incidents highlight the need for standardized protocols in record-keeping. They advocate for clearer retraction notices that explain the reasons behind withdrawals and preserve access to the original content, regardless of its status. Without such measures, the integrity of the scientific archive—and the public’s trust in it—remains at risk.

As the scientific community continues to grapple with ethical oversight, this episode serves as a reminder that even the most revered figures in science are not immune to scrutiny. The withdrawal of Planck’s papers, however obscure, invites a sober reflection on how we preserve, interpret, and learn from the past.