Repeatability
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Experimental science demands repeatability of results, in part because there are so many ways that experiments can go wrong. There are several famous experiments whose results were later retracted or discredited. The most common problem is simply overlooking an important source of noise or bias; such sources sometimes become apparent only with extensive experience with complex equipment or theories. Some errors are introduced when the experimenter's desire for a certain result unconsciously influences selection of data (a problem which today is avoided by double blind protocols). There have also been cases of deliberate scientific misconduct.
Famous experimental errors
- N-rays (1903)
- A reported faint visual effect that experimenters could still "see" even when the supposed causative element in their apparatus had been secretly disconnected.Template:Citation needed
- Kaufmann (1906) – claimed experimental disproof of special relativity
- Published in Annalen der Physik and said to be the first journal paper to cite Einstein's 1905 electrodynamics paper. Kaufman's paper stated that his results were not compatible with special relativity. According to Gerald Holton, it took a decade for the shortcomings of Kaufmann's test to be realised: during this time, critics of special relativity were able to claim that the theory was invalidated by the available experimental evidence. <ref>Jeremy Bernstein, "Einstein" (1973) pp.81–85 — Kaufmann experiment</ref>
- Adams (1924) – premature verification of the gravitational redshift effect.
- A number of earlier experimenters claimed to have found the presence or lack of gravitational redshift, but Adams' result was supposed to have settled the issue ("definitively established", RWL "Relativity" <ref>Albert Einstein, "Relativity" (15th ed., 1954) — Appendix 3 has a note from the translator mentioning Adams' "definitive" result.</ref>). It is no longer considered credible, one of the more charitable interpretations being that his data may have been contaminated by stray light from Sirius A [1]. The first "reliable" confirmations of the effect appeared in the 1960s.<ref>F. Wesemael, "A comment on Adams' measurement of the gravitational redshift of Sirius B", Royal Astronomical Society, Quarterly Journal (ISSN 0035-8738), 26, Sept. 1985, 273–278 [2]</ref>
- First reproducible artificial diamond (1955)
- Originally reported in Nature in 1955 and later. It later transpired that diamond synthesis should not have been possible with the apparatus. Subsequent analysis indicated that the first gemstone, which secured further funding, was natural rather than synthetic. Subsequent artificial diamonds are assumed to be genuine.<ref>Bovenkerk et al., "Errors in diamond synthesis", Nature 365 19 (1993) "Scientific Correspondence"</ref>
- Oops-Leon Particle (1976)
- Data from Fermilab in 1976 appeared to indicate a new particle at about 6 GeV which decayed into electron-positron pairs. Subsequent data and analysis indicated that the apparent peak resulted from random noise. The name is a pun on upsilon, the proposed name for the new particle and Leon M. Lederman, the principal investigator. The illusory particle is unrelated to the Upsilon meson, discovered in 1977 by the same group.
- Infinite Dilution of Antibodies (1988)
- Jacques Benveniste was a French immunologist who in 1988 published a paper in the prestigious scientific journal Nature describing the action of very high dilutions of anti-IgE antibody on the degranulation of human basophils, findings which seemed to support the concept of homeopathy. Biologists were puzzled by Benveniste's results, as only molecules of water, and no molecules of the original antibody, remained in these high dilutions. Benveniste concluded that the configuration of molecules in water was biologically active. Subsequent investigations have not supported Benveniste's findings, which are now cited as an example of pathological science.
- Cold fusion (1989)
- Since the announcement of Pons and Fleischmann in 1989, cold fusion has been considered to be an example of a pathological science. Two panels convened by the US Department of Energy, one in 1989 and a second in 2004, did not recommend a dedicated federal program for cold fusion research.
Alleged scientific misconduct cases
- Rupp had been considered one of the best experimenters of his time, until he was forced to admit that his notable track record was at least partly due to the fabrication of results.<ref>Michael Brooks, on Emil Rupp, "Convenient untruths", New Scientist, No2630 (17 Nov 2007) pp. 58–59
- See also Jeroen van Dongen, "Emil Rupp, Albert Einstein and the Canal Ray Experiments on Wave-Particle Duality: Scientific Fraud and Theoretical Bias" http://arxiv.org/abs/0709.3099</ref>
- Materials physics (~1999)
- A succession of high-profile peer-reviewed papers previously published by Hendrik Schön subsequently found to be using obviously fabricated data.
- Production of Element 118 (1999)
- Element 118 was announced, then the announcement withdrawn by Berkeley after claims of irreproducibility. The researcher involved, Victor Ninov, denies doing anything wrong.
See also
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