Problematic physics experiments
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Physics experiments that attempt to be the first in their category tend to have a higher failure rate than normal. Experimenters are sometimes involved in a race to be first or are under other pressures to perform, equipment is often being pushed to its limits, and experimental techniques are sometimes too new for their true reliability rates to be fully appreciated at the time.
Consequently, some experiments become well-known that are subsequently considered not to be quite as reliable as first thought. This page provides a partial listing.
Contents |
[edit] Troublesome mainstream experimental results
- Eddington (1919) – test of general relativity’s light-bending predictions
- Multiple serious issues with selectivity and methodology.
- First reproducible artificial diamond (1955)
- Originally reported in Nature 176 5- 54 (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.
- “Errors in diamond synthesis” NATURE - VOL 365 - 2 SEPTEMBER 1993 [1]
- Hafele-Keating (1971) – time dilation in clocks flown around the world
- The effect itself does not seem to be generally in dispute, but questions have been raised about their approach and statistical analysis, given the large degree of variation between clocks. It is claimed (Kelly) that under the revised USNO guidelines issued the following year, the H-K results would have had to have been rejected as unreliable. This does not seem to be disputed.
- Nanotechnology (~1999)
- A succession of high-profile peer-reviewed papers previously published by Hendrik Schon 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- Element 118 was announced, then the announcement withdrawn by Berkeley after claims of irreproducibility.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 denies doing anything wrong. [2]
[edit] Current mainstream results to be treated cautiously
- Identification of dark matter - the existence of unseen dark matter of unknown composition and origin shadowing clumps or conventional matter is an ad hoc hypothesis designed to explain the shortfall in general relativity’s predictions for the cohesiveness of rotating galaxies. Some recent experiments claim to have confirmed the existence of dark matter, e.g., by finding a similar discrepancy between the general theory’s gravitational lensing predictions and observed data. Whether this means that we have identified a consistent distribution of dark matter or just shown that GR’s equations are consistently wrong, is still a moot point. (see: unsolved problems …)
- ”Transverse redshift” tests of special relativity (performed transversely (Hasselkamp 1978) or longitudinally (the Ives-Stilwell experiment and many other experiments since) invoke test theory to imply that the effect may be unique to special relativity, and to justify using equipment calibration and data analysis to decide between only two possible outcomes: a Lorentz redshift (SR) or no shift (classical theory). Under current test theory, experimenters finding redshifts exceeding the SR predictions are entitled to calibrate the additional redshift away and still claim the result as supporting special relativity, since this action in no way favours the SR prediction over the null prediction.
[edit] ”Rehabilitated” experiments
- Isaac Newton – a prism splits light rather than modifying it
- Was originally claimed to be an unreplicable result by other researchers, leading to claims that Newton had fabricated his result (see: “glassworks”).
- Michelson and Morley (1887) – null result for aether wind
- Was reputedly dismissed by Michelson’s colleagues at the time as a “failed” experiment (ref: R.S. Shankland), the M&M test eventually became considered a historic experimental result (Lorentz claimed analytical errors in Michelson’s earlier solo experiment, though).
[edit] “Inexplicable” results
Some experimental results suffer from the lack of a coherent theory to explain them. Some of the better-known recent ones are:
- - multiple experiments, and many claims and counter-claims.
- claimed gravitational anomalies
- recently the Podkletnov disk and Hayasaka-Takeuchi gyro experiments generated some interest (and some heavy scpticism). See antigravity
