observational errors. So if no fundamental error exists in the observations, then Lorentz's theory is abolished. In Abraham's theory, the deviations amount to 3-5 percent; these are also outside the margin of observational error. But the possibility of errors which sums up in a way that such a difference comes out, would be, nevertheless, still possible.
Planck: If the correction of the theoretical numbers necessary for a complete explanation of the observations, is outside the observational error, then it is conceivable to me that if one take them into account and make corrections in addition to the errors of observation, we could come closer to Lorentz's theory than Abraham's. From the mere fact that the deviations of a theory are smaller, a preference would not follow for it.
Bucherer: I would like to return to the remark of the speaker that my theory is not sufficiently developed to be discussed here even further. I was intensely engaged with it and its consequences, and found that it is not substantially better than the earlier theory of Lorentz and the later theory of Lorentz. One objection is to be found in the fact that in the dispersion theory the electromagnetic masses create difficulties; in all other respects the theory of deformed electrons at constant volume and of the corresponding deformed system performs the same as the newer theory of Lorentz. With the extension of Planck's considerations on my electron, I could not say what would be the consequences of this reasoning for my electron. But I want to call attention to some theoretical points. The dynamics of the electron is not only testable by the deflection of Becquerel rays. Abraham has alluded to the need of attributung to the Lorentz-electron a special internal energy. That difficulty seems greater to me than the deviation from Kaufmann's measurements. Against Einstein's theory of relativity certain objections can be raised. He uses Maxwell's equations, but ignores that certain conditions are not met, namely the validity of the divergence theorem of electrical force.
After I had recognized that the existing theories, including mine, do not meet the requirements, I have asked me the question, if it is possible to be consistent with experience while keeping Maxwell's equations and the principle of equality of action and reaction. This is possible when we rely on the following principle: the ponderomotive force between two systems in relative uniform motion to each other, by consideration of the sign, is the force calculated from the Maxwell-Lorentz equations acting upon a system which is arbitrarily regarded as at rest. Of course, in this model the concept of the aether is not present, because as soon as I introduce relative motions and define the coordinate system in an arbitrary body of the dynamic system, I give up the aether theory. I have followed the consequences and I came to some conclusions in relation to Kaufmann's measurements, which I want to tell. First, the rigid electron would come into question. Due to the relative theory we come to the conclusion that other forces act when the Becquerel rays are directed, not parallel but obliquely to the capacitor plate. Here an easy possibility would be given to test the principle of the relative theory on the basis of Maxwell's equations, it is sufficient to let Becquerel rays fly obliquely to the electric or magnetic field. For vertical motion you get oddly enough the same forces as Lorentz. I have considered whether the deviation of Kaufmann's measurements is based on the fact that an angle is formed.
Runge: I would like to ask Mr. Planck the following: In the contradiction, which he finds when he calculated β from the first value, it has to be taken care whether a small change in the observation already produces a large change in the value. One would have to calculate the interval of β, for which there are still permissible errors of observation.
Planck: β is proportional to . A small change of y' would do much because y' is small compared to z'. The errors, however, are already so great that one can not use the values; we would have to eliminate the exterior values in any case, we can not use them for the theory. To Bucherer, I want to ask a question. Can your equations be brought into a Lagrangian form? And if so, what value has the Lagrangian function H for your newer theory, did you investigate it?
Bucherer: No, I have not studied it and could not decide it at this moment.
Planck: That would be very important, as due to the Lagrangian form the
