Psychokinesis - Scientific View

Scientific View

If PK were to exist as claimed by some experimenters, it would violate some well-established laws of physics, including the inverse square law, the second law of thermodynamics, and the conservation of momentum, according to Martin Gardner and Thomas Gilovich. Hence scientists have demanded a high standard of evidence for PK, in line with Marcello Truzzi's dictum "Extraordinary claims require extraordinary proof". When apparent PK can be produced in ordinary ways—by trickery, special effects or by poor experimental design—scientists accept that explanation as more parsimonious than to accept that the laws of physics should be rewritten.

The late Carl Sagan included telekinesis in a long list of "offerings of pseudoscience and superstition" which "it would be foolish to accept (...) without solid scientific data" though even highly improbable claims may possibly be eventually verified. He placed the burden of proof on the proponents, but cautioned readers to "await—or, much better, to seek—supporting or disconfirming evidence" for claims that have not been resolved either way. Nobel Prize laureate Richard Feynman advocated a similar position.

In their 1991 research paper Biological Utilization of Quantum Nonlocality, Nobel Prize laureate Brian Josephson and coauthor Fotini Pallikara-Viras proposed that explanations for both psychokinesis and telepathy might be found in quantum physics. Gerald Feinberg's concept of a tachyon, a theoretical particle that travels faster than the speed of light has been advocated by some parapsychologists who claim that it could explain psychokinesis. Haakon Forwald (1897-1978) a Swedish electrical engineer suggested that psychokinesis of objects could occur due to gravitational fields produced by mental influence acting on neutrons in the atoms inside the objects, however his hypothesis has never been proven and critics have pointed out his hypothesis is faulted by general relativity.

There is a broad consensus, including several proponents of parapsychology, that PK research, and parapsychology more generally, has not produced a reliable, repeatable demonstration.

In 1984, the United States National Academy of Sciences, at the request of the US Army Research Institute, formed a scientific panel to assess the best evidence from 130 years of parapsychology. Part of its purpose was to investigate military applications of PK, for example to remotely jam or disrupt enemy weaponry. The panel heard from a variety of military staff who believed in PK and made visits to the PEAR laboratory and two other laboratories that had claimed positive results from micro-PK experiments.

The panel criticised macro-PK experiments for being open to deception by conjurors, and said that virtually all micro-PK experiments "depart from good scientific practice in a variety of ways". Their conclusion, published in a 1987 report, was that there was no scientific evidence for the existence of psychokinesis. Parapsychology advocates responded by accusing the panel of bias.

Research with random number generators has been influenced by signal detection theory, viewing the effect of PK as weak but real "signal" hidden in the "noise" of experimental results. An effect too weak to be demonstrated in a replicable experiment would still show up as a statistically significant effect in a large set of data. To test this, parapsychologists have carried out meta-analyses of large data sets, with apparently impressive positive results. This has in turn been criticized as an invalid use of meta-analysis, since the original studies are too dissimilar for the resulting statistics to be meaningful. A 2006 meta-analysis of 380 studies found a small positive effect within the margin that could be explained by publication bias.

Physicist Robert L. Park finds it suspicious that a phenomenon should only ever appear at the limits of detectability of questionable statistical techniques. He cites this feature as one of Irving Langmuir's indicators of pathological science. Park argues that if PK really existed it would be easily and unambiguously detectable, for example using modern microbalances which can detect tiny amounts of force.

PK hypotheses are also tested implicitly in a number of contexts outside parapsychological experiments. Gardner considers a dice game played in casinos, where gamblers have a large incentive to affect the numbers that come up. This is in effect a large sample-size test of the same hypothesis as the J. B. Rhine dice experiments, but year after year the house takings are exactly those predicted by chance. Psychologist Nicholas Humphrey argues that many experiments in psychology, biology or physics assume that the intentions of the subjects or experimenter do not physically distort the apparatus. Humphrey counts them as replications of PK experiments (but implicitly so) in which PK fails to appear.

In the book Parapsychology: The Controversial Science (1991), British parapsychologist Richard S. Broughton, Ph.D, wrote of the differences of opinion among top scientists encountered by Robert G. Jahn, director of the (now-closed) PEAR laboratory, regarding the psychokinesis research that the lab was engaged in at the time.