User:JimWae/Time

http://www.britannica.com/EBchecked/topic/596034/time

Peter A. Angeles

 * time. 1. That in which events are distinguishable in terms of the relations of before and after, beginning and end. (Sometimes this is thought of as nonspatial medium [realm, order] in which things change and events take place.) 2. That which is distinguished by the relationships of before and after, beginning and end, and which is inseparable from change. 3. The measurable aspect of duration (instants, intervals)&mdash;a particular point, moment, period, portion, or part of duration or of what endures. 4. The irreversible succession of instants (events, segments, points, intervlas, durations,) conceived of as a linear progression or only as a directional line. 5. A measure of change, or change itself observed, as in the poistional change of the sun or the hands of a clock, or the qualitative change of the color of an object or sharpness of a sound or sight. Such changes are often used as a reference for comparison to other changes; for example the cycle of the moon is called a month, and is used as a measure of time to compare to the cycle of light and darkness which we call a day.


 * time (Plato). Time is "the moving image of eprfect eternity." By this plato meant that time is an imperfect imitation of the timeless unchanging realm of perfect ideal forms. Change, succession, and hence time are merely the results of the mind's inablity to grasp things all at once (SUB SPECIE AETERNITAS) in their entirety. Time is a product peculiar to the mind and dependent on its functions.


 * time, absolute (Newton). Some of the basic points in Newton's concept of absolute time: 1. Absolute time is independent of natural (physical) events and is prior in existence to natural events. 2. Absolute time is mathematical time, a homogeneous mathematical order. 3. Its essential nature is to flow uniformly without regard and without relation to any external thing. 4. Absolute time is eternal. It flowed before the creation of the universe. 5. Absolute itme is directional. It has an absolute direction and movement. Newton's concept of absolute time was opposed to the concept of relative time, which held that time and space were sets of relations among objects and were never independent of objects and of change.
 * space/time (Leibniz). Leibniz' theory of space/time has two aspects, the objective or ontological and the subjective or epistemological: 1. Space and time are not absolute and are not independently real as entities but are the order (relationship) of succession and coexistence in which real entities (the MONADS) are related to the coexistence of things. Time is relative to the cosuccession of things. 2. Space and time are systems of relations abstracted by the mind from particular contingent experiences (and at that not clearly perceived). In this sense space and time are logical constructs expressing relations based on experin=ence and are not substances, or real entities. See SPACE(LEIBNIZ)


 * time (Kant). 1. The intuited infinite continuum (of all present and possible experience) and 2. the immediately given innate a priori form by which the given is experienced as a flow. See SENSE, INTERNAL AND EXTERNAL (KANT); SPACE (KANT); SPACE/TIME (KANT)


 * space/time (Kant). According to Kant: 1. We do not derive our ideas of space and time by abstracting them from experience. 2. We do not derive our ideas of space and time from experience of succession, precedence, simultaneity, concurrence, coexistence, proximity, etc. These experiences themselves presuppose our having the ideas of space and time. 3. Space and time are A PRIORI intuitions. They are pure, intuitive, nonceptual ideas. 4. Knowledge of space and time is (a) clearly, immediately, intuitively possessed; (b) not framed or given by concepts; (c) all experiences presuppose this intuition and depend upon it for a form. 5. Space and time are "pure" intuitions in the sense that their essence is known prior to experience and is not an outcome of experience. 6. Space and time are the form of experience&mdash;the form which all experience takes&mdash;and are not the content of experience. 7. Space and time structure experience (sensation) in the very act of its being experienced (sensed) and known. 8. Space and time apply to anything we know through our experience (senses). 9. Time applies to anything we experience as an inner flow of consciousness (and since consciousness cannot be consciousness unless it is a flow, then time is constantly an aspect of consciousness). See SPACE (KANT).

The Cambridge Dictionary of Philosophy
time, "a moving image of eternity" (Plato); "the number of movements in respect of the before and after" (Aristotle); " the Life of the Soul in movement as it passes from one stage of act or experience to another" (Plotinus); "a present of things past, memory, a present of things present, sight, and a present of things future, expectation" (Augustine). These definitions, like all attempts to encapsulate the essence of time in some neat formula, are unhelpfully circular because they employ tempral notions. Although time might be too basic to admit of definition, there still are many questions about time that philosophers have made some progress in answering by analysis both of how we ordinarily experience and talk about time, and of the deliverances of science, thereby clarifying and deepening our understanding of what time is...

Absolute versus relative and relational time. In a scholium to the Principia, Newton declared that "Absolute, true and mathematical time, of itself and from its own nature, flows equably without relation to anything external." There are at least five interrelated senses in thich time was absolute for Newton. First, he thought that there was a frame-independent relation of simultaneity for events. Second, he thought that there was a frame-independent measure of duration for non-simultaneous events. He used 'flows equably' not to refer to the above sort of mysterious "temporal becoming," butinstead to connote the second sense of absoluteness and partly to indicate two further kinds of absoluteness. To appreciate the latter, note that 'flows equably' is modified by 'without relation to anything external'. Here Newton was asserting (third sense of 'absolute') that the lapse of time between two events would be what it is even if distributions and motions of material bodies were different. He was also presupposing a related form of absoluteness (fourth sense) according to which the metric of time is intrinsic to the temporal interval.

Leibniz's philosophy of time placed him in agreement with Newton as regard the first two senses of 'absolute', which assert the non-relative of frame-independent nature of time. However, Leibniz was very much opposed to Newton on the fourth sense of 'absolute'. According to Leibniz's relational conception of time, any talk about the length of a temporal interval must be unpacked in terms of talk about the relation of the interval to an extrinsic metric standard. Furthermore, Leibniz used his principles of suffiicient reason and identity of indiscernibles to argue against a fifth sense of 'absolute', implicit in Newton's philosophy of time, according to which time is a substratum in which physical events are situated. On the contrary, the relational view holds that time is nothing over and above the structure of relations of events.

Einstein's special and general theories of relativity have direct bearing on parts of these controversies. The special theory necessitates the abandonment of fram-independent notions of simultaneity and duration. For any pair of space-like related terms in Minkowski space-time there is an inertial fram in which events are simultaneous, another frame in whichthe first event is temporally prior, and still a third in which the second event is temprally prior. And the temporal interval between two timelike related events depends on the worldline connecting them. In fact for any &epsilon; > 0, no matter how small, there is a worldline connecting the events whose proper length is less than &epsilon;. (This is the essence of the so-called twin paradox.) The general theory of relativity abandons the third sense of absoluteness since it entails that the metrical structure of space-time covaries with the distribution of mass-energy in a manner specified by Einstein's field equations. But the heart of the absolute-relational controversy - as focused by the fourth and fifth senses of 'absolute' - is not settled by the relativistic considerations. Indeed, opponents from both sides of the debate claim to find support for their positions in the special and general theories. See also EINSTEIN, METAPHYSICS, RELATIVITY, SPACE, SPACE-TIME. -- John Earman and Richard M. Gale, ''University of Pittsburgh

Editor: Dagobert D. Runes
Time: The general medium in which all events take place in succession or appear to take place in succession. All specific and finite periods of time, whether past, present or future, constitute merely parts of the entire and single Time. Common-sense interprets Time vaguely as something moving toward the future or as something in which events point in that direction. But the many contradictions contained in this notion have led philosophers to postulate doctrines purporting to eliminate some of the difficulties implied in common-sense ideas. The first famous but unresolved controversy arose in Ancient Greece, between Parmenides, who maintained that change and becoming were irrational illusions, and Heraclitus, who asserted that there was no permanence and that change characterized everything without exception. Another great controversy arose centuries later between disciples of Newton and Leibniz. According to Newton, time was independent of, and prior to, events; in his own words, "absolute time, and mathematical time, of itself, and from its own nature, flows equably without regard to anything external." According to Leibniz, on the other hand, there can be no time independent of events: for time is formed by events and relations among them, and constitutes the universal order of succession. It was this latter doctrine which eventually gave rise to the doctrine of space-time, in which both space and time are regarded as two systems of relations, distinct from a perceptual standpoint, but inseparably bound together in reality. All these controversies led many thinkers to believe that the concept of time cannot be fully accounted for, unless we distinguish between perceptual, or subjective, time, which is confined to the perceptually shifting 'now' of the present, and conceptual, or objective, time, which includes til periods of time and in which the events we call past, present and future can be mutually and fixedly related. See Becoming, Change, Duration, Persistence, Space-Time. -- Ralph B. Winn

Space-Time: The four-dimensional continuum including the three dimensions of space (length, width and height) and one of time; the unity of space and time. The concept was first suggested by H. Minkowski and immediately afterward incorporated by A. Einstein into his (special) theory of relativity. The former contended that nothing can exist or be conceived of as physical apart from space-time; for every object must have not only length, width and height, but also duration in time. As a result, a complete description and location of an object must be given in terms of four coordinates. Space-Time is mathematically grounded in world-points, or durationless geometrical points, as the foundation of all four-dimensional measurement; and in world-lines, or geometrical lines cutting across the four dimensions. An enduring geometrical point thus beconus a geometrical line (or possibly a curve) in space-time. Space-Time is physically conceived of as a general structure determined by the relationship among world-events, or four-dimensional events. The universe of four dimensions (the omniverse, as it may be called) includes space with all of its events and objects as well as time with its changes and motions. As such this four-dimensional universe must be changeless and motionless, insofar as things move and change only when taken in abstraction from time, or rather when space and time are regarded as separate. According to the classical or Newtonian theory, space-time is separable in an absolute way into the two elements, space and time; on the other hand, according to either the special or the general theory of relativity, this separation is not possible in an absolute sense but is relative to a choice of a coordinate system.

A somewhat different, metaphysical interpretation of Space-Time was formed by S. Alexander and C. L. Morgan. According to their doctrine of Emergent Evolution, space-time is the matrix of the world, out of which have emerged matter, life, mind, and Deity. The world as we know it has evolved out of the original space-time. --Ralph B. Winn

Time
Time is a fundamental component of our measuring system and has long been a major subject of art, philosophy, and science. Whether it is possible to formulate a noncontroversial definition, applicable to all fields, remains an issue for scholars.

In physics and other sciences, time is considered a fundamental quantity, i.e. one that cannot be defined in terms of other quantities because those other quantities – such as velocity, force, energy – are already defined in terms of that fundamental quantity (in this case, time; scientists also consider space one of these fundamental quantities). Within science, the only definition needed or possible is an operational one, in which time is defined by the process of measurement and by the units chosen.

Among philosophers, there are two distinct viewpoints on time. One view is that time is part of the fundamental structure of the universe, a dimension in which events occur in sequence. This is the realist's view, to which Sir Isaac Newton subscribed, and hence is sometimes referred to as Newtonian time. The opposing view is that time is part of the fundamental intellectual structure (together with space and number) within which humans sequence events, quantify the duration of events and the intervals between them, and compare the motions of objects. In this second view, time does not refer to any kind of entity that "flows", that objects "move through", or that is a "container" for events. This view is in the tradition of Gottfried Leibniz and Immanuel Kant. These two views differ on whether time can be measured, or is itself part of the measuring system.

Temporal measurement has occupied scientists and technologists, and was a prime motivation in astronomy. Periodic events and periodic motion have long served as standards for units of time. Examples include the apparent motion of the sun across the sky, the phases of the moon, the swing of a pendulum, and the beat of a heart. Currently, the international unit of time, the second, is defined as a certain number of hyperfine transitions in Cesium atoms (see below). Time is also of significant social importance, having economic value ("time is money") as well as personal value, due to an awareness of the limited time in each day and in human lifespans.

2012
Time is both the experience that events have duration, can be sequenced, and have intervals between them, and also is the quantity with which the intervals and durations of events are measured, typically using a clock.

Time is quantified in comparative terms (such as longer, shorter, faster, quicker, slower) or in numerical terms using standardized units (such as seconds, minutes, hours, days)


 * Time is an aspect/feature of events. It is an aspect that can be situated on a number line - a dimension. To avoid taking a POV on the substantivalist-relationist issue, something like this:
 * Time is a dimension of events — in which events can be sequenced, have duration and intervals between them quantified, and with which rates of change can be measured.


 * Saying time is "a dimension of events" does not imply that such a "dimension" exists independently of events. I think it is wise to heed the caution contained in the first paragraph that defining time is a challenge, cease trying to begin "Time is the...", and return to giving a broad description of the basic temporal concepts.
 * Time is not "the sequence of events" - a sequence of events is simply a sequence of events. Events only have sequence because by "an event" we already understand that a temporal component is involved. Nor is time "the sequence of ALL events" - as some events cannot be established to have a definite sequence.
 * While "succession" an exceedingly better term than "progression", for the same reasons as above, time is still not identical to any "succession of events", but rather events are successive because events are already understood to have a temporal component, and not all events are located at the same point on that dimension.--JimWae (talk) 19:37, 14 August 2012 (UTC)