Timelines is an inquiry into the nature of time, both as an apparent feature of the external physical world and as a fundamental feature of our experience of ourselves in the world. The principal argument of Timelines is that our coventional ideas about time are largely mistaken and that what we think of as independent physical time is actually our calibration of a certain relation between events. Namely, the relation between time-keeping events and the causal sequential differences of physical processes (...) which are real and independent of us. (shrink)

It continues to be alleged that superluminal in uences of any sort would be inconsistent with special relativity for the following three reasons: they would imply the existence of a ‘distinguished’ frame; they would allow the detection of absolute motion; and they would violate the relativity of simultaneity. This paper shows that the first two objections rest upon very elementary misunderstandings of Minkowski geometry and on lingering Newtonian intuitions about instantaneity. The third objection has a basis, but rather than invalidating (...) the notion of faster-than-light influences it points the way to more general conceptions of simultaneity that could allow for quantum nonlocality in a natural way. (shrink)

The clock hypothesis of relativity theory equates the proper time experienced by a point particle along a timelike curve with the length of that curve as determined by the metric. Is it possible to prove that particular types of clocks satisfy the clock hypothesis, thus genuinely measure proper time, at least approximately? Because most real clocks would be enormously complicated to study in this connection, focusing attention on an idealized light clock is attractive. The present paper extends and generalized partial (...) results along these lines with a theorem showing that, for any timelike curve in any spacetime, there is a light clock that measures the curve’s length as accurately and regularly as one wishes. (shrink)

The differential aging effect is shown to be valid in any physically reasonable extension of the special theory of relativity which includes a description of accelerating observers. Einstein's controversial assumption—the clock hypothesis—is avoided. Instead, it is sufficient to assume accessibility—that it is possible to travel from one inertial observer to another and then return to the first in a reasonable manner. Since Minkowski space-time displays this accessibility property, there must be an error in Sachs's quaternion development of general relativity. No (...) assumptions concerning measurements—proper time—of accelerating observers are necessary, nor are assumptions concerning special features of their motion—uniform acceleration. (shrink)

A. L. Kroeber, who together with C. Kluckhohn wrote a now classical review of the concept of culture (1958), claimed that the most significant accomplishment of anthropology in the first half of the twentieth century was the extension and clarification of the concept of culture. In the book mentioned they analyzed about 300 different definitions of the concept. In a critical review of Kroeber's and Kluckhohn's book their colleague L. A. White contests Kroeber's claims and writes: “On the contrary, I (...) believe that confusion has increased as conceptions of culture have been multiplied and diversified” (1954, p. 461). (shrink)