Relativity in Terms of Measurement and Ether Lajos Jánossy's Ether-Based Reformulation of Relativity Theory

Scientific Paper
Title	Relativity in Terms of Measurement and Ether Lajos Jánossy's Ether-Based Reformulation of Relativity Theory
Read in full	Link to paper
Author(s)	Lászl? Székely
Keywords	Relativity, Measurement, Ether, Lajos Jánossy
Published	2008
No. of pages	33

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Abstract

In his monograph Theory of Relativity Based on Physical Reality, Hungarian physicist Lajos Jánossy develops the complete Einsteinian formalism of relativity theory by analysing the process of measurement, the systems of measures created in this process and experimental data expressed in terms of measures. He demonstrates that based on a simple principle (which he calls the Lorentz principle) and its generalization the whole formalism of the original theory may be developed in conformity with the notions of common sense without mathematizing physical reality, so that the new way of development is of the same heuristic power as the original one. His analysis makes it clear that the allegedly revolutionary new notions of space and time follow not from physical experiences but from Einstein's positivist philosophical commitments. Having established the place and role of a privileged (but not absolute) reference system, at the second level of his theory Jánossy connects this system to the carrier of electromagnetic phenomena which he also assumes to be the carrier of the gravitational and other physical fields. Although he uses the term 'ether', he explicitly rejects the old theories of this entity and attributes to it dynamic properties. In the last section of the paper Einstein's and Jánossy's ether concepts are compared and it is argued that despite the parallelism between the two concepts, from Jánossy's point of view Einstein's ether is too mathematical to cure the inverted relation between mathematics and physics characteristic for Einstein's relativity.

Overview

This is a review essay by László Székely of the Institute for Philosophical Research of the Hungarian Academy of Sciences, written to recover a body of work he considers unjustly neglected: the reformulation of relativity theory carried out by the Hungarian physicist Lajos Jánossy (1912–1978), chiefly in his 1971 monograph Theory of Relativity Based on Physical Reality. Székely places Jánossy alongside Herbert Ives and Simon Prokhovnik as "one of the classics of the field" of physical, Lorentzian-style interpretations of relativity, and notes that Harvey Brown named Jánossy a forerunner in Physical Relativity (2005) and that J. S. Bell expressed appreciation for his contribution in "How to Teach Relativity?" (1976).

Two claims organise the essay. The first is that Jánossy derives the entire Einsteinian formalism — special and general — from an analysis of measurement, without at any point invoking new notions of space and time; the mathematics is identical, the physical interpretation is not. The second is that what Einstein added over and above the formalism is philosophical rather than empirical: the "allegedly revolutionary new notions of space and time follow not from physical experiences but from Einstein's positivist philosophical commitments." Székely is careful throughout to record that Jánossy accepted the mathematical content of special and general relativity as empirically correct, and that he never took part in the Soviet anti-relativity campaigns — most of his critical work appeared while official Soviet ideology endorsed Einstein, and he was attacked from both directions, ending his career sidelined by Hungarian Einsteinians as "an anti-relativist dinosaur."

Jánossy's reformulation

Measures and measured things

The metatheoretical foundation has two interlocking parts: the priority of physics over mathematical formalism, and the deliberate adoption of common sense as a norm for theory construction. Jánossy's charge against Einstein is not that the formulas are wrong but that the epistemological relation is inverted — that Einstein "projects mathematical formulae into the physical world" and constructs physical reality by hypostatising mathematical ideas. Székely quotes Jánossy's own account of how he came to this view while teaching relativity at Manchester: "as my technique presenting the theory improved, my own belief in the adequateness of the concepts vanished." Elsewhere Jánossy calls the modern attitude to common sense "a cult of irrationality", in which "the scientific character of a theoretical claim is measured by the extent of its absurdity", against which he sets the thesis that "a scientific way of thinking cannot be but the refinement, deepening and further development of everyday thought."

The technical expression of this is a strict distinction between physical quantities and measures. Quantities exist independently, with their own laws; measures are freely chosen human representations, which Jánossy notated with Roman letters against Gothic letters for the quantities. This lets him defuse the transformations: "The fact that a transformation type (1) mixes the measures of time and space coordinates does not seem to be of particular importance and it does not imply any properties of space and time." To avoid the conclusion that nothing can then be known, he introduces distinguished measures — those whose sums and products themselves express significant physical quantities. Charge is his worked example: the additivity of charge measures, and the appearance of their product in Coulomb's law, is not trivial but "a question which can be decided experimentally."

Applied to length and time, this yields two independent scales rather than Einstein's hybrid one. An ideal solid rod is defined as a rod with which an additive length scale can be obtained. An ideal clock is defined without light signals at all: assume a region where Newton's first law holds, observe free particles, and adjust local clocks so that the law is satisfied. Székely notes that Newton's first law is deducible from Leibniz's principle of sufficient reason, so that Jánossy's definition inherits that pedigree. Separately, Jánossy shows one can build scales from light signals alone by the radar method, provided light is assumed isotropic relative to a chosen system; whether the resulting coordinates are coherent is then an empirical test of that assumption.

Jánossy's theorem and the basic system

The central result Székely calls Jánossy's theorem: if there is a coherent system of measures in which light appears isotropic with speed c relative to a system S, then there exists a group of transformations of measures carrying it to systems M′ in which light appears isotropic relative to any S′ in uniform rectilinear motion relative to S, and conversely. The group is the Lorentz group — no new transformations, but a new derivation and a new meaning. Crucially, the theorem "is not about inertial systems: it is valid independently of whether Lorentz systems are inertial or not."

The a priori analysis then forces a disjunction. Either rods and clocks are never deformed by motion, in which case exactly one Lorentz system has its light-based and rod-based measures coinciding, and every other system's velocity relative to it is measurable; or rod-and-clock measures always coincide with Lorentz measures, in which case there is a definite basic system and rods and clocks moving relative to it are deformed according to the Lorentz formulae. The observed contraction and time dilation show that the second alternative holds. Székely presents this as the heuristic power of the approach: the existence of a privileged system is derived from the relativistic effects, not assumed.

The same analysis is turned on Einstein. Isotropic propagation in two systems in relative motion is geometrically impossible if (i) the region's spatial relations define one definite space and (ii) the same measures are used in both. Jánossy rejects (ii), explaining the difference in measures by real deformation of instruments. Einstein, having excluded any basic system and requiring symmetric effects, must reject (i) — which, Székely argues after the Hungarian philosopher Melchior Palágyi, "fragments physical reality into an infinite number of reference systems."

The Lorentz principle

On the strength of the Michelson-Morley and Kennedy-Thorndike null results and the transverse Doppler effect, Jánossy states the Lorentz principle: "The law of nature is such that provided S is a real physical system, then the Lorentz deformed systems S* are possible systems obeying the same laws as S." Székely emphasises that this is a physical reformulation of Einstein's relativity principle with identical observational predictions, and argues it answers the standard charge of ad hoc-ness: the Lorentz transformation is deduced from considerations about measurement, and the principle rests on observational data, whereas Einstein posits the equivalence of inertial systems as an unexplained axiom. A dynamic version is added — "if a connected physical system is carefully accelerated [with respect to the ether] then, as a result of the acceleration, it suffers a Lorentz deformation" — with the mechanism sketched as atoms in a rod resettling into a new dynamic equilibrium after acceleration relative to the ether, so that the deformation lags observably behind continuous acceleration.

General relativity and the ether

Jánossy's general theory rests on the ideal-solid-rod definition and on a generalisation of the Lorentz principle. Rods are ideal if the quadratic distance formula has solutions for arbitrary sets of points — an overdetermined system, so its solubility is informative. If it fails, Jánossy insists, this tells us about the rods, not about the "structure of physical space": "We do not think, however, that such a conclusion has any meaning." Székely links this to Poincaré's thesis that hypotheses are never about geometry or physics alone but about both together. The generalised Lorentz principle is then explicitly methodological: seek generalisations of homogeneous-region laws that reduce correctly in the limit, preserve the Lorentz principle locally, and can be expressed in tensors and covariant operators — with Jánossy insisting it remains "a question of experiment" whether the resulting laws are correct or even invariant.

Four consequences follow. General relativity is primarily about the propagation of light, so the metric appears first as the propagation tensor of light and only later coincides with the gravitational metric. The equality of inertial and gravitational mass becomes a secondary implication rather than a foundation. Non-Euclidean spaces are spaces of measures only. And geodesic motion in four dimensions is dismissed: "if we call those orbits 'straight' then we lose completely the meaning of what is usually called straight."

The ether is introduced strictly as the carrier of electromagnetic waves — following Maxwell's question, relative to what do the waves propagate at c? — and explicitly not as a state of absolute rest: "The concept of 'absolute rest' is a metaphysical concept which must be rejected"; different parts of the ether may well stream at different velocities on cosmic scales. In general relativity it acquires states, strains and inhomogeneities, and Jánossy proposes that the metric tensor "represents the state of the ether which is the carrier of all physical fields." His closing hypothesis is that gravitational force is a self-force: internal forces holding a closed system together propagate at c in the ether, a gravitational field makes that propagation inhomogeneous, and the resulting imbalance accelerates the system — with free fall corresponding to the case where internal propagation remains nearly homogeneous relative to the particle, so that no resultant self-force arises.

Einstein's ether versus Jánossy's

The final section presses Jánossy's own claim of kinship with the later Einstein — who reintroduced an ether for the metric field and conceded that special relativity needed a dynamical account of rod and clock deformation. Székely finds the parallel real but limited: Einstein's ether is gravitational only, Jánossy's carries electromagnetism too; Jánossy's is a three-dimensional entity while Einstein's is hard to picture as other than a four-dimensional continuum; and Jánossy characterises its states with physical terms (pressure, strain, density) used metaphorically, whereas Einstein's terms are imported from mathematics. The verdict is that Einstein's late conversion to an ether "does not cure the epistemologically inverted relation between mathematics and physics." The essay closes by raising, without answering, the possibility that the mathematisation it has criticised might not be a methodological error at all — "is it possible that in its ultimate ontology the world around us is not of a physical but a mathematical nature?"

Assessment

The essay's principal virtue is its scrupulousness. Székely does not claim that relativity is wrong, that its predictions fail, or that Jánossy found different formulas; he states repeatedly that the mathematics is the same and the predictions identical, and that the dispute is interpretive. That is the honest framing of a Lorentzian position, and it is rarer in this literature than it should be. The historical service is real too: Jánossy is genuinely under-cited relative to Ives and Prokhovnik, and the biographical section — Schrödinger's student, cosmic-ray researcher of international standing, stepson of György Lukács, attacked both by Einsteinians and by Soviet ideologues — establishes that his criticism cannot be filed under Cold War politics. The measurement-theoretic apparatus is the most substantive part. Distinguishing quantities from measures, and defining an ideal clock by requiring Newton's first law rather than by radar synchronisation, is a genuinely clarifying move that separates the conventional from the empirical content of the theory; it anticipates much of what Brown later argued at length. The "antenna problem" point also lands: Einstein's theory does not explain how spacetime structure constrains matter, and calling a theory simpler when it declines to address a question is, as Székely says, close to tautology.

The weaknesses are those of any dynamical-ether interpretation, and the essay does not fully confront them. Most importantly, the position is empirically indistinguishable from Einstein's by construction — Székely says so — which means the argument must be settled on philosophical grounds, and there the essay tends to assert rather than establish. That Einstein's space-time notions follow from "positivist philosophical commitments" rather than from physics is stated as a finding of Jánossy's analysis, but the analysis shows only that a Lorentzian reading is available, not that the relativistic reading is a philosophical imposition; the same reasoning would let one say Jánossy's undetectable basic system follows from his realist commitments. The appeal to common sense is doing heavy lifting it cannot bear: common sense is not a reliable guide to domains outside ordinary experience, and the essay's own example — that on the Minkowski view the interval between a person's birth and death becomes the same kind of thing as the distance from Budapest to London — is an appeal to intuition, not an argument.

There is also a real cost that is acknowledged but not weighed. Jánossy's framework "breaks the ontological symmetry of the relativistic effects": the mutual contraction that two observers each attribute to the other becomes, for him, one real contraction and one apparent one. Since the symmetry is exactly what is confirmed — in the reciprocal time dilation observed between the ground and circumnavigating atomic clocks in the Hafele-Keating experiment and its many successors, and in the mutual consistency of muon-lifetime measurements analysed in either frame — the theory buys its intuitive picture by declaring half of a confirmed symmetry illusory, while offering no experiment that could reveal which half. The dynamic Lorentz principle nominally offers one: deformation should lag during continuous acceleration, so that instrument states briefly depart from the Lorentz values. But no magnitude, no timescale and no proposed experiment are given, and the acceleration-independence of clock rates has since been tested to high precision — muons in storage rings experience accelerations of order 10¹⁸ g with lifetimes still given by γ alone. That is the one place where Jánossy's theory could have been distinguished from Einstein's, and it is precisely where the essay is thinnest. Finally, the gravitational self-force hypothesis is offered only as a sketch, illustrated on an electric charge and, in Székely's own words, not proceeded with further.

See also

• László Székely
• Relativity
• Special Relativity
• General Relativity
• Ether
• Albert Einstein
• Hendrik Lorentz
• Lorentz Transformation
• Length Contraction
• Michelson-Morley Experiment
• Simultaneity
• Speed of Light
• Ernst Mach