SUMMARY OF ERRORS IN THE FOUNDATIONS OF PHYSICS 1899 - 1999.

I suppose the worst error of all is in not accepting that a postulation is incorrect, when strange consequences result.

The emergence of Relativity around the turn of the 20th century, in particular Einstein's Theories of Relativity (SR and GR) [1], gave physicists new tools for research into the fundamental laws of nature, but also created new opportunities for making wrong assumptions and other mistakes.

1. The trail of wrong assumptions starts at the Principle of Relativity, which is described in various ways, but popularly means that the laws of physics must be the same in all inertial frames of reference, e.g. "Energy = Mass times the speed of light (c) squared", must stay true in any frame of reference moving with constant speed relative to another, where c squared is a constant of proportionality. Similarly, another law, "energy is equal to Planck's constant (denoted h) times frequency", also shows that the mathematical forms of the laws of physics often include a constant of proportionality having appropriate dimensions of Mass, Length and Time for the equation to be dimensionally valid.
That is, the laws of physics are proportional relationships and the factors of proportionality can change without violating the law. and must do so when necessary. Einstein and just about everybody else (and since!) assumed that the equations were the laws and that the constants could not change. They must certainly stay constant in any chosen inertial frame of reference, as is shown below.
Relativistic changes in mass, length, and resonant frequencies, as predicted by Enstein's theories of relativity reveal a problem with the above equations:- the same relative change in energy is correctly predicted by both the above equations when energy is added without resulting motion (e.g. a change in height in a gravity field in the same frame of reference), but, when unrestricted motion results, experiments show that there is an opposite relativistic change in frequency for the same increase in energy so the two equations predict opposite changes if the proportionaality factors stay constant!
For physics to be coherent and a theory to be viable, THIS MUST NOT HAPPEN.
Experiments show that frequency increases in the gravity case, but decreases for unrestricted motion, and the only possibility that prevents the above anomaly is by c and h changing their values in moving frames, 'h' needing to increase and c to decrease. But Einstein declared the speed of light c to be a universal constant, probably due to the above assumption.
The error, therefore, is that everyone, it seems, wrongly assumes that the words "the laws of physics must be the same" includes the value of the factor of proportionality.
But, the laws of physics are proportional relationships, represented by equations. When relativity (or a country) changes the sizes of the units involved in an equation, the rules of mathematics demand that the value of any dimensioned factor of proportionality needs to be (re)calculated from the new sizes of the units involved.
THIS ERROR IS STILL BEING MADE, after more than 100 years!
When mass is changed by relativity in accelerated (moving) frames, only one (unique) set of changes to Mass, Length, and Time units can exist that produces coherence between physics equations [2], and that set requires the values of c and h to change. Considering the fact that the only variable in the fine structure universal constant is the product hc, the relativistic changes to h and c must be equal and opposite. By combining this fact wth the two energy equations, the unique relativistic changes can be derived.
Many of the areas of criticism, anomalies and contradictions emanating from SR can be traced back to this error, which invalidates SR, as that theory is based on the postulation that the measurement of c (in a vacuum) is a universal constant.
It may be of interest to note that if measured by instruments in the moving frame of reference the value of c will not have changed, as the length and time unit dimensions of those instruments will have changed in the same proportions as the wavelength and frequency of the light.
Other areas of criticism, anomalies and contradictions emanating from SR can be traced back to his assumptions that relativistic changes are caused by speed and gravity, whereas energy is clearly the common cause.
Correct (coherent) relativity transformations for mass, length, and time units, and the dynamic values for c and h, plus new mass-velocity equations, are given in a manuscript specifying Natural Relativity (NR) [2], which the Physical Society of America refused to publish in their appropriate journal (they don't give any valid reasons, but do seem to be protecting SR from being invalidated/replaced). The dynamic values of c and h found in NR (and other derivations on this web site) cause the two energy equations to predict the same value for a unit of energy.
"To err is human, to forgive, divine", but to deliberately perpetuate errors is . . . . . just another error to be forgiven?
It is not surprising, then, to find that SR does not comply with any principles of relativity and also disagrees with some experiments, as is shown in NR (which agrees with all valid experiments, has no known flaws, and complies with all principles of physics and relativity).

2.  ANOTHER ERROR is closely connected to that given above, as follows.
Constants of proportionality must have fixed values in an inertial frame of reference (otherwise they are not constants, so let us call this "the principle of local constants"), yet the accepted relativistic changes in a chosen frame of reference predict that the supposed universal gravitational constant of proportionality (G) apparently changes with height (did no one notice?). THIS MUST NOT HAPPEN EITHER, and appears to have been completely overlooked.
Physicists have cheerfully accepted from other considerations that G is a universal constant, but when the logic of relativity is applied to its dimensions, The value of G changes, whereas it is widely accepted that it should be constant. If a set of relativistic changes produces coherence between most undisputed physics equations, then the rare equation that fails to conform must be incorrect. This points to Newton's law of gravity being incorrectly interpreted, and this surprising fact (gravity cannot emanate from mass) and the correction to it, are given in The Natural Source of Gravity , this website.
This news is nearly 100 years late, too.

3.   Perhaps, the following may not be considered by some to be an ERROR, but violation of the principle of Conservation of Total Energy should qualify (in my opinion). That principle, together with the principle of equivalence of mass and energy, demands that applied energy causes mass to increase (decrease) in its own frame of reference. Then, that change in the mass of electrons in atoms causes changes in emitted frequencies and atomic size (relativistic effects), as shown by the spectroscopic equations produced by Neils Bohr in 1913 [3]. It has become noticeable, therefore, that some authors (and text books) derive predictions of relativistic effects from dubious manipulations of physics equations and theories without any energy being supplied (or removed) to enable mass to change. No energy supplied (or removed) equals no mass change equals no relativistic effects. Also, apparent mass changes in external frames can have no relativistic effects as they are entirely dependent on the state of motion of the observer. And, also, it is long accepted that inertial motion changes nothing (because there is no ongoing energy exchange). Unfortunately, SR seems to have set a bad example here.
The above errors are, I believe, at the root of all the problems with SR.

References.
1. Max Born, Einstein's Theory of Relativity, 2nd edition(Dover Publications, New York, 1962).
2. D. V.Connell, "Natural Effects of Applied Energy, Motion and Gravity on Mass", Phys. Essays,22,3,402-412(2009).
3. Henry Semat, Introduction to Atomic and Nuclear Physics, 4th edition, (Chapman and Hall, London, 1962), p.233.