Ricardo Libertario Carezan, an Argentine physicist created the Theory of Autodynamics in 1940s, first published in 1951.
The primary claim of Autodynamics is that the equations of the Lorentz transformation are incorrectly formulated to describe relativistic effects, which would invalidate special relativity and general relativity. The effect of the revised equations proposed in Autodynamics is to cause particle mass to decrease with particle velocity, being exchanged with kinetic energy.
Autodynamics proponents cite a 1946 experiment by William W. Buechner and Robert J. Van de Graaff which failed to observe any "missing energy" when a high-energy electron beam stopped in a calorimeter; this result rejected the idea that the energy losses reported for the scattering of beta-rays by heavy nuclei could be accounted for by the emission of neutrinos (as had been suggested by Ellis & Wooster and Meitner & Orthmann.
Although a legitimate question in the 1940s, the result is clearly consistent with mainstream relativity and the Standard Model of particle physics. Carezani claims that the results are consistent with Autodynamics and, for unclear reasons, inconsistent with relativity. Autodynamics proponents generally claim that all published observations of the neutrino are due to experimental errors.
Carezani moved to the United States and in 1982 conducted an accelerator experiment at the Stanford Linear Accelerator Center. The experiment gave a result consistent with mainstream physics and inconsistent with Carezani's expectations, but he responded with a modified Theory of Autodynamics which included an accelerator-specific effect.
A 1999 article in the popular magazine Wired quotes Pierre Noyes, a professor at the Stanford Linear Accelerator Center, as claiming "most scientists consider Autodynamics little more than a 'crackpot theory'".
Despite this, Noyes performed an experiment in an attempt to compare the predictions of Special Relativity and Autodynamics, but concluded that the values calculated by Specil Relativity were significantly closer to what was observed. Carezani later argued that the experiment was not relevant for comparing the two theories by pointing out that Autodynamics applies specifically to decay cases, yet the electrons in the Noyes experiment received energy from the external medium.
Nobel Laureate Dr. Luis Alvarez of the University of California, Berkeley was interested in helping Carezani design an improved version of this experiment. According to Lee Smolin, a physics professor at the Perimeter Institute and adjunct at the University of Waterloo, that there has been "no serious attempt to make an argument or to discuss experimental data that refute their basic claims". Autodynamicists reject these claims.