A reported faint visual effect that experimenters could still "see" even when the supposed causative element in their apparatus had been secretly disconnected.
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. Kaufmann'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.
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" ). 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 . The first "reliable" confirmations of the effect appeared in the 1960s.
First reproducible synthetic diamond (1955)
Originally reported in Nature in 1955 and later. Diamond synthesis was later determined to be impossible with the apparatus. Subsequent analysis indicated that the first gemstone (used to secure further funding) was natural rather than synthetic. Artificial diamonds have since been produced.
Claimed Detection of Gravitational Waves (1970)
In 1970 Joseph Weber, an electrical engineer turned physicist, and working with the University of Maryland, reported the detection of 311 excitations on his test equipment designed to measure gravitational waves. He utilized an apparatus consisting of two one ton aluminum bars, each a separate detector, in some configurations being hung within a vacuum chamber, or having one bar displaced to Argonne National Laboratory, near Chicago, about 1,000 kilometers away, all for further isolation. He took extreme measures to isolate the equipment from seismic and other interferences. But Weber’s criteria for data analysis turned out to be ill-defined and partly subjective. By the end of the 1970s Weber's work was considered spurious as it could not be replicated by others. Still Weber is considered one of the fathers of gravitational wave detection and inspiration for other projects such as LIGO.
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.
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. In 2007 Nature reported that the American Chemical Society would host an invited symposium on cold fusion and low energy nuclear reactions at their national meeting for the first time in many years.
Rupp (1926) – dubious canal-ray experiments.
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.
Materials physics (~1999)
A succession of high-profile peer-reviewed papers previously published by Jan Hendrik Schön were subsequently found to have used obviously fabricated data.
Production of element 118 (1999)
Element 118 (oganesson) was announced, and then the announcement withdrawn by Berkeley after claims of irreproducibility. The researcher involved, Victor Ninov, denies doing anything wrong.
List of experimental errors and frauds in physics Wikipedia
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.