Time never changes

The Nature of Time Einstein elaborated on his definition of time and made it clear that his objective was to get rid of the concept of Absolute Time. This he did, but we now need to understand exactly what he put in its place. Time is one of the trickiest words in human language, for we use it in a number of different senses which do not at all refer to the same thing. For example, we say of a journey that it occurred in time, that it started at a specific time and that it lasted for a period of time. In fact, we carry around with us, and work within, three significant concepts of time. Harris identifies these as Passage, Movement and Measurement. Passage (Flow): We are conscious of our own past experiences which brought us to the present and to which we can never return. We know, too, that the present will also become past and will take us into the future. We express these certainties by saying that Time passes and will carry all of us along with it. This is sometimes called Absolute Time. Movement: Time brings change, and change is simply a succession of events. Events occur in space and in time and it is the sequence of events, one after the other, that gives us our sense of the passage of time. Measurement: We compare events in terms of the order in which they follow each other, and how long each event lasts. This involves comparison, and we compare what is to be measured with a suitable measuring device, such as a clock. In contrast, we do not speak about Space in the same way, but use words such as space, place and length or distance to specify the different senses in our concept of Space. If we did something similar for Time, we might, with Dingle, use the words eternity, instant and duration for passage, movement and measurement respectively. We can now see that Einstein's definition of time is concerned with Movement (instants) and Measurement (durations) where durations are intervals between instants. In other words, it provides a metric which allows us to compare different events. About eternity, or the Absolute Time in which these events take place, this definition, deliberately, has nothing at all to say. Max Born, puts it this way: "" absolute time has no physical reality. Time-data have a significance only relatively to definite systems of reference." In our everyday lives, to measure time we use a uniform and consistent periodic sequence of change with which we can compare other changes in which we are interested. This provides us with a standard measuring device (a calibrated clock) which allows us to count the passing moments as Time marches on. Our units of time " second, minute, hour, day and year etc. " are relative to the periodic rotation of the earth about its axis and its equally periodic orbit about the sun. All terrestrial clocks are therefore calibrated to measure, as accurately as possible, these periodicities. Our unit for space, the metre, is similarly tied to the planet. Originally defined as one ten-millionth of the distance from the Earth's equator to the North Pole at sea level, it has been redefined a number of times and since 1983 has been expressed as the length of the path travelled by light in a vacuum during a time interval of 1R60;299,792,458 of a second. Results Enquiring more closely into Einstein's definition of time, he tells us that: "It is essential to have time defined by means of stationary clocks in the stationary system, and the time now defined being appropriate to the stationary system we call it 'the time of the stationary system." He was even more explicit in his book The Meaning of Relativity (1922 and later editions) when he said: "It is essential to note that this definition of time relates only to the inertial system K, since we have used a system of clocks at rest relative to K. The assumption which was made in the pre-relativity physics of the absolute character of time (i.e. independence of time of the choice of the inertial system) does not follow at all from this definition." In other words, in Special Relativity, there is no Absolute Time and we must define new units and devices to measure it in each inertial system. We are not allowed to carry the units of measurement from one system to another. This then is the resolution of the paradox "the travelling twin must not use the terrestrial units of time because the periodicities on which they are based will have different values in his inertial frame. Instead, the terrestrial units should be corrected using the Lorentz factor in order to provide the units appropriate to the moving inertial frame. In other words, the correction must be applied, not to the instants and durations in the moving frame, but to the units that are used to measure them. We can best illustrate the result by using a standard example of the paradox to calculate the length of travelling twin's round trip for both the currently accepted approach and the alternative suggested here. Consider the case of a twin travelling from Earth to a star system at a distance d = 4 light years away. He is travelling in a rocket whose velocity, v, is 80 percent of the speed of light (v = 0.8c). At this relative velocity, his earthbound sibling will see the traveller's return journey time as t = 2d/v = 10 years. We must next calculate the time interval experienced by the travelling twin. For a velocity of 80% of the speed of light, the Lorentz factor (W30;1 " v2R60;c 2) has a value of 0.6. The standard calculation of the traveller's total flight time is then made as follows: " In this twin's rest frame, the distance to the star system dr = 0.6d = 2.4 light years. " The time taken by the rocket to make the return journey is therefore tr = 2dr/v = 6 years. " Therefore, on his return, the traveller is 4 years younger than his earthbound sibling. However, if we use the Lorentz factor to define the appropriate units of time in the moving inertial frame (rather than applying it to the number of light years involved) we have the following set of calculations: " The travelling twin will see the earth taking longer to orbit the sun, so his year is longer than a terrestrial year. Applying the Lorentz factor for a velocity of v = 0.8c, we find that 1 year in the travelling twin's inertial frame is equivalent to 1.666666667 earth years; " As he sees it, the distance to the star system is therefore dr = 4 x 1.666666667 = 6.666666667 equivalent terrestrial light years. " His return journey time, measured on board the rocket, is therefore tr = 2dr/v = 10 years. In other words, when the travelling twin returns to earth he will be exactly the same age as his earthbound sibling. The Twin Paradox is therefore a real paradox, and is of the falsidical kind. Indeed, it is very similar to Zeno's paradox of Achilles and the tortoise. The fallacy at its heart is the assumption that the units of time defined for the terrestrial inertial frame can be carried over to all external frames. This is expressly forbidden by Einstein's definition of time and would, in any case, have the effect of making terrestrial time an Absolute Time, something, as we have seen, that Einstein was at pains to avoid. Conclusions - It follows that Time Dilation does not correspond to any reality. It is merely a chimera that arose from a subconscious assumption that our terrestrial units of time are universal and absolute, and the consequent failure to define appropriate units of measurement for the external moving frame. The fact that Einstein himself overlooked this essential requirement of his own theory underpins the pervasive and ill-defined nature of our sense of 'Time.' What then of the experiments which have confirmed the reality of Time Dilation? All of these experiments involved the use of 'accurate' clocks (or other uniform periodic changes) to measure the time intervals in the moving inertial frames. world on commercial jet flights.