In Newtonian dynamics, two events were separated by two kinds of interval, one being distance in space, the other lapse of time. As soon as it was realised that all motion is relative which happened long before Einstein , distance in space became ambiguous except in the case of simultaneous events, but it was still thought that there was no ambiguity about simultaneity in different places. The special theory of relativity showed, by experimental arguments which were new, and by logical arguments which could have been discovered any time after it became known that light travels with a finite velocity, that simultaneity is only definite when it applies to events in the same place, and becomes more and more ambiguous as the events are more widely removed from each other in space.
This statement is not quite correct, since it still uses the notion of "space. But, in addition, there is between neighbouring events a quantitative relation called "interval," which fulfils the functions both of distance in space and of lapse of time in the traditional dynamics, but fulfils them with a difference. If a body can move so as to be present at both events, the interval is time-like. If a ray of light can move so as to be present at both events, the interval is zero.
If neither can happen, the interval is space-like. When we speak of a body being present "at" an event, we mean that the event occurs in the same place in space-time as one of the events which make up the history of the body; and when we say that two events occur at the same place in space-time, we mean that there is no event between them in the four-dimensional space-time order. All the events which happen to a man at a given moment in his own time are, in this sense, in one place; for example, if we hear a noise and see a colour simultaneously, our two perceptions are both in one place in space-time.
When one body can be present at two events which are not in one place in space-time, the time-order of the two events is not ambiguous, though the magnitude of the time-interval will be different in different systems of measurement.
Relativity. The theory and its philosophy|INIS
But whenever the interval between two events is space-like, their time-order will be different in different equally legitimate systems of measurement; in this case, therefore, the time-order does not represent a physical fact. It follows that, when two bodies are in relative motion, like the sun and a planet, there is no such physical fact as "the distance between the bodies at a given time"; this alone shows that Newton's law of gravitation is logically faulty.
Fortunately, Einstein has not only pointed out the defect, but remedied it. His arguments against Newton, however, would have remained valid even if his own law of gravitation had not proved right. Time not a Single Cosmic Order. The controversy about the aether thus becomes rather unreal. Undoubtedly, when light-waves travel, events occur, and it used to be thought that these events must be "in" something; the something in which they were was called the aether.
But there seems no reason except a logical prejudice to suppose that the events are "in" anything. Matter, also, may be reduced to a law according to which events succeed each other and spread out from centres; but here we enter upon more speculative considerations. Physical Laws. Eddington has emphasised an aspect of relativity theory which is of great philosophical importance, but difficult to make clear without somewhat abstruse mathematics.
The aspect in question is the reduction of what used to be regarded as physical laws to the status of truisms or definitions.
Eddington, in a profoundly interesting essay on "The Domain of Physical Science," [Footnote 1] states the matter as follows Easily read eBooks on smart phones, computers, or any eBook readers, including Kindle. When you read an eBook on VitalSource Bookshelf, enjoy such features as: Access online or offline, on mobile or desktop devices Bookmarks, highlights and notes sync across all your devices Smart study tools such as note sharing and subscription, review mode, and Microsoft OneNote integration Search and navigate content across your entire Bookshelf library Interactive notebook and read-aloud functionality Look up additional information online by highlighting a word or phrase.
Institutional Subscription. Free Shipping Free global shipping No minimum order. Mathematical Preliminaries 2.
Relativity and Newtonian Mechanics 3. The Principle of Special Relativity 4. Empiricism, Rationalism and Special Relativity 5. Special Relativity and Conventionalism 6. The Commensurability of Classical and Relativistic Mechanics 7. More Mathematics 8. The Path to General Relativity 9. An Outline of General Relativity Relativity and Covariance Spacetime and Geometry Index.
Powered by. Ford develops the problem in Einsteinian terms much more forcefully and clearly than Wilcox. Similarly, Fitzgerald states that "special relativity modifies our concepts of space and time it implies the relativity of simultaneity" Does God utilize some unique space-time system, and are the other systems wrong? He offers a series of very interesting alternatives, some concerning the view that God is an actual entity and others that he a living person. But are Einstein and Whitehead compatible? His description of simultaneity, his doctrine of the uniformity of nature, his doctrine of alternate time-systems, and his principle of kinematic symmetry all exemplify his appeal to our direct, immediate experience of nature.
Experience is also the central method of his approach to problems in metaphysics. The elucidation of immediate experience is the sole justification for any thought; and the starting point for thought is the analytic observation of components of this experience. Notice the Kantian flavor in the following statement and compare it with the passage quoted above. The justification of such constructs does not lie in their derivation from what is given by the senses" It must be remembered that presentational immediacy is not simply the projection of properties derived from causal efficacy onto regions in the contemporary world.
Rather, presentational immediacy describes the vivid experience of the extensive relations of the contemporary region. Whitehead gives us a concrete example of his meaning when he writes, "If we are gazing at a nebula a thousand light-years away, we are not looking backward through a thousand years" PR Instead Whitehead would argue that we are experiencing an immediate region of external space. I think this aspect of presentational immediacy has been de-emphasized by many Whiteheadian commentators.
An encyclopedia of philosophy articles written by professional philosophers.
For Einstein, the only knowledge we have is confined to our awareness of the world as causally past. This point is overlooked in most discussions of the so-called paradoxes of the relativity of simultaneity. For Einstein, the problems of simultaneity in the contemporary world can only be analyzed after the fact -- after the events of the contemporary world have entered the causal past.
It may be described as having "a foot in two camps, for it represents the property of the future as embodied in the past" R This physical interpretation of gravity allows Whitehead to speak concretely about the causal influence of the past on the future. In describing the experience of the simplest grade of actual entity, Whitehead writes: The experience has a vector character, a common measure of intensity. In the Special Theory of Relativity Einstein, as is well known, denied the ontological status of the "ether. This point may be generalized to include the relation between any scientific theory and philosophical system.
We must not absolutize any particular scientific theory as being "true. References 1. Milic Capek. The Philosophical Impact of Contemporary Physics. New York: Van Nostrand Reinhold, Paul Fitzgerald. Robert R. Unpublished dissertation, Vanderbilt, Robert Palter. Chicago: University of Chicago Press, Paul Arthur Schillp. Albert Einstein: Philosopher-Scientist. LaSalle, Illinois: Open Court, John T. The important point is that the two components exist simultaneously and are in constant interaction. The latter two are concerned primarily with the first metric of his theory.
For a popular presentation of their work see Clifford M. The arguments are 1 Einstein gives light signals too prominent a place in our lives; 2 there are other means of sending messages; 3 Einstein does not take account of the agreement within one time-system of the meaning of simultaneity.
Strain loci provide the systematic geometry, while durations share in the "deficiency of homology characteristic of the physical field which arises from the peculiarities of the actual events" PR Too many discussions of presentational immediacy overlook this aspect and focus only on the role of presentational immediacy as the projection of the causal past onto the contemporary world.
On the Theory of Relativity: Philosophical Aspects
For Whitehead the alternate time-systems form the basis of the uniform structure of spacetime. For Einstein there is only one spacetime structure which varies depending on the presence of matter. Thus it is appropriate to think of the special theory as describing the structure of spacetime in the absence of matter. Matter warps this uniform spacetime structure, producing curved spacetime.
For this reason, the geometrical interpretation seems better suited to both the special and general theories. The gravitational field and the propagation of light are both aspects of the physically contingent world and consequently are not necessarily uniform. In R Whitehead moves from considerations of geometry to physics.
Notice that the movement from uniformity to contingency corresponds with a movement from the analysis of the contemporary region to an analysis of the relationship between the past and future. If velocities were not reciprocal, the velocity of light in different frames of reference could be different. However, "prior" usually implies much more. Misner, et al. The first metric defines geometrical relations.
The second metric defines physical relations. Whitehead admits that if "space" means physical space, then physical space is contingently warped. Whitehead expresses this view when he states that "if space-time be a relatedness between objects, it shares in the contingency of objects, and may be expected to acquire a heterogeneity from the contingent character of objects" H Notice that the physical relations between events create physical objects which endure through time. I believe that the distinction between geometrical and physical relations and the correlation of the first metric with the "abstract measures of spatio-temporal process" R 87 indicate that in R Whitehead already has made the distinction between physical space and the extensive continuum which characterizes his treatment of these issues in PR.
However, there is no requirement in his philosophy of nature that gravitation be propagated in this fashion.