It is still perhaps not widely appreciated that in 1905 Einstein used his postulate concerning the ‘constancy’ of the light-speed in the ‘resting’ frame, in conjunction with the principle of relativity, to derive numerical light-speed invariance. Now a ‘weak’ version of the relativity principle (or, alternatively, appeal to the Michelson—Morley experiment) leads from Einstein's light postulate to a condition that we call universal light-speed constancy. which is weaker than light-speed invariance. It follows from earlier independent investigations (Robertson [1949]; Steigler [1952]; (...) Tzanakis and Kyritsis [1984]) that this condition is none the less sufficient to derive the Lorentz transformations up to a scale factor, given the well-known kinematic principle of ‘reciprocity’. In this paper, we follow Robertson and explore the kinematics consistent with universal light-speed constancy without imposing reciprocity, and we recover the Lorentz transformations by further appeal only to the weak relativity principle and spatial isotropy. (shrink)

INTERNATIONAL STUDIES IN THE PHILOSOPHY OF SCIENCE Vol. 10, number 2, 1996, pp. 127-140. R.M. Nugayev. Why did the new physics force out the old ? Abstract. The aim of my paper is to demonstrate that special relativity and the early quantum theory were created within the same programme of statistical mechanics, thermodynamics and Maxwellian electrodynamics reconciliation. I’ll try to explain why classical mechanics and classical electrodynamics were “refuted” almost simultaneously or, in other words, why the quantum revolution and the (...) relativistic one both took place at the beginning of the 20th century. I’ll argue that the quantum and relativistic revolutions were simultaneous since they had a common origin – the clash beyween the mature theories of the second half of the 19th century that constituted the “body” of classical physics. The revolution’s most dramatic point was Einstein’s 1905 photon paper that laid the foundations of both special relativity and the old quantum theory. Hence the dialectic of the old theories is crucial for theory change. Later, classical physics was forced out by the joint development of quantum and relativistic subprogrammes. The title of my paper can be reformulated in Bruno Latour’s terms: The Einstein Revolution or Drawing Models Together. -/- . (shrink)