Jack Dikian
August 2001
Introduction
When thinking about a world where the linearity of time is no longer maintained – that is, a world where the 24 hour measure of time is no longer divided in equal intervals; the time that elapses between 3pm and 3.15pm is different from the time that elapses between say, 4pm and 4.15pm.
It become very clear that the word “time” is used as a means of measuring the passing of time. So a clock measures intervals of time, but not of time itself. The immediate question, therefore, is what is it that we are measuring? We can use all sorts of instruments and fall back on common descriptors such as;
“the years are going by so quickly”,
“Time is like a river”,
“Time flies by when we are having fun”
These don’t, however, tell us what it is that we are measuring. We are still left without an understanding of what exactly is an interval of time.
The Psychology
Despite the preciseness of our instruments we are still measuring physical time in contrast to a more subjective personal time. Psychologically, time seems to be over before we know it. The past only exists as memory and we can’t remember the future. So, therefore we are always in the moment. Interestingly enough, unlike other spatial dimensions of perception, time is not directly available to any sensory system but can only be sensed through the unfolding of events in the world we live in.
Before examining the mathematics and/or the physics of what we call time it may be useful to briefly look at the psychological construction of time that we use to make meaning of our world.
The orderly nature of our world is born in part from the fact that events’ spatial characteristics are structured in and over time. Speech, body movements and walking gaits in which the sequence of words or actions unfold with a characteristic rhythm and tempo over a given time span. This spatio and temporal structure influences how an event is perceived and remembered, as well as providing some guidance over the accuracy with which the event’s velocity and total duration are subsequently judged. We routinely decide (or to be more précis estimate) whether there is sufficient time to cross a street ahead of an approaching car.
The activities we undertake in everyday life also vary in cyclic patterns over the course of a day or a course of a seasion and provides a scheme that serves to coordinate those individuals in any particular society. Different cultures have different conceptualizations and attitudes toward time which can be reflected in the overall pace of life. In any individual, the temporal perspective and their relative orientation toward the past, present, and future is central to one’s mental well-being and the degree of ego strength displayed in coping with life’s difficulties. As well, in the clinical analysis of timing disorders mechanisms mediating circadian-driven behaviors are quite distinguished from those governing the internal clock and sensitivity to an event’s duration and overall velocity.
The Physics
Firstly, we all tend to perceive time as a smooth flowing and continuous motion. We in the usual course of life never experience time in chunks, slices, or something characterized by broken gaps. This is somewhat consistent with our perception of other natural phenomena such as energy, and the space around us. However, at the quantum level of matter energy is not released continuously - there is a limit to how small a change in energy an atom can experience - it is released in discrete quanta by the emission of photons. This lends itself to the question;- are individual frames of time so small that it only gives the appearance of being smooth and continuous.
In experiments using instruments that can 'slice' moments in time to a small enough granularity in order to capture a chemical reaction and dealing with time at the Femtosecond level, that is one thousandth of one trillionth of a second, (1/1,000,000,000,000,000th) there seems to be no indication of time passing in discreet steps. Time still appears to flow smoothly. It is off course entirely possible that if it does move in discrete steps that we have not yet reached a level small enough to observe it. The smallest measurement of time that can have any meaning in contemporary physics is a 'Planck Time', and is equal to 10-43 seconds.
That is a decimal point followed by 43 zeros and then 1 (0.00000000000000000000000000000000000000000001)
Interestingly, there is nothing in the laws of physics to suggest that time actually flows from the past through the present and into the future. At the subatomic level there is no distinction between the past and the future. By studying these particles it would be impossible to determine the order in which the events took place. At this level there is no way to distinguish the past from the future by simply looking at each particle pairs.
However, we are clearly able to discern the arrow of time or the direction of time at the macrosporic level. We would never see for example, a bottle hitting the floor and breaking before it actually falls off the table. So it seems at the macro level (the level we experience reality) there is a natural inbuilt arrow of time pointing from the past to the future. The distinction between the past and future is expressed mathematically by thermodynamics.
The second law of thermodynamics states that the entropy of a closed system always increases, entropy being the measure of disorder. In other words disorder will always increase and if left to its own devices, a system will run to disorder, and not order, giving us an arrow of time.
One of the most peculiar qualities of time is the fact that it is measured by motion and may possibly therefore emerge through motion. Our perception of “time” may therefore be mostly an illusion. Our memory creates the illusion of the past. Our conscious perception of events gives us the feeling of the present. The future is a mental construct patterned on the memory of experience. The concept of time emerges as our mind tries to make sense of the world we are in.
In general relativity matter produces curvature in space-time, and this concept can be extended to moving objects showing that moving objects can also curve space-time. In an expanding universe, time is related to the expansion of space. Slower time is associated with slower expansion. This extra dimension is not a time dimension in which we can travel. Time is just thought of as the presence of motion and forces and is caused by the expansion of space. Expansion of space, here, is the prime mover behind all the action, it imparts time as the presence of motion and forces to matter in an area of space.
The relationship of the clock and speed of light is fixed at a basic level in a given region of space. Clocks may measure a different speed of light if located in a region of space which is different from where light is being observed. For example a clock on earth measuring speed of light in a region next to a distant neutron star where time is slower will measure a slower speed. While a clock located on the surface of neutron star will measure a faster speed of light in distant space.
Moving objects produce moving wave like curvature in space. Once within the vicinity of the moving object mass-less particles like photons are picked up and carried forward by the time differential which is present in these waves. Also the velocity of light is decreased by the slower time within the moving wave. Within the moving object like earth light is pulled along in the direction of motion and it also slows down to conform to the slower time around the earth.
The faster we travel through the dimensions of space, the slower we travel through the dimension of time, and vice versa. Thus an astronaut zooming along at light speed has used up all their speed 'allocation' in the space dimensions, and as a consequence does not travel through time. This would seem to suggest that the speed of light really is the limiting speed within the universe, and if we had no motion at all through space then we would be travelling at light speed through time. The more movement we make across space the less we make in the direction of time.
