Time, Page 1

Introduction

Time has been the subject of many a debate amongst philosophers, physicists and the laymen alike. And indeed, it is a very peculiar object. You can't see it, you can't feeling it on your skin like you can the wind, you can't hear it whistle past us, nor can you smell it or taste it. It is something that we infer.

This topic of time is a big one. I won't be suprised if it turns out larger than the Universe article, in which case this text will get smaller and smaller. I find it to be quite an interesting one because it is the ultimate in Brainteasers. It will stretch your mind to its limits.

Most, if not all, of what I talked about in the Universe article will be reiterated here. Like the other topics discussed, the concepts of this one will be integrated with the universe article as well. For now, just disregard what was discussed in the Life article. I want to talk about time on its own without making things harder by including other theories and concepts that I'm sure you have enough trouble swallowing to begin with.

The Symmetry of Time

I guess our first step would be to identify our normal definition of time. For us, time is something that can be measured. We measure it in terms of minutes, hours, days, years, light years, as well as speed and distance. Time is sometimes refered to as an arrow. In a sense, time is a vector quantity. By our definition it has a magnitude and a direction. This magnitude should be a first step into realising something is wrong. What is the magnitiude of time? One second per second? It doesn't take a univeristy mathematics student to realise that a second per second isn't possible. Let's keep this in mind for now.

Direction is the other characteristic of time. We consider it to flow from past to future. In other words, we always see the sun rise in the east and set in the west, not the other way around. From our perspecitve, the world is time assymetric.

However, we have a problem. Like the analogy I used in the Universe article, "Take acceleration for example. Acceleration is given by the formula "a=(v-u)/t" where a = acceleration, v = the final velocity, u = the initial velocity and t = time. So, acceleration is the final velocity minus the initial velocity all divided by the total time taken. There is also something called decelaration, where a mass slows down from a higher velocity to a lower one (as opposed to acceleration, where a body speeds up). Mathematically, deceleration uses the same formula described above. You know when something is decelerating when your answer after calculation is a negative.

"Suppose now that we look at time a little differently. A car is seen to accelerate when we view time as flowing from past to future. However, if we view time as flowing from future to past, the car appears to be decelerating. The mathematics still applies independant of which way time flows. Time flowing from future to past will be deceleration, which is applicable by mathematical law.

So, it can be seen that mathermatical law doesn't destinguish between time direction. In fact, the flow of time is symmetric according to law. It doesn't destinguish between a car accerlerating from past to the future or a car decelerating from future to past. Or, in fact, a car accelerating from future to past or a car decelerating from past to future. It's simply a matter of linguistics."

We view time as a measurement. It is usually a measurement of some physical event. Like the sun rising and setting. Or an object traveling a certain speed for a certain distance. Anything physical is covered under physics. In every sense of the word, time would be regarded as a part of physics. Cosmologists refer to space as space-time. That's just one simple example. If time is physics, and physics is law, and law is time symmetric, then time must be a symetric quantity.

The Question of Time

The flow of time can mean anything we want it to mean. It all depends on how we define what one second is. Time was recently redefined in terms of light speed. Basically, the time elapsed between two separate events means something different to each individual. One day for us humans on earth will be different to one day for aliens on mars. Which leads me to my next point that I discussed in the Universe article, "The .... point that needs to be raised is the idea of time being non-existant. I know this goes against everything that is ingrained within our souls, but if you think about it, it is an interesting concept. For example, try explain the last time you went to the dentist without refering to days, minutes, hours, the sun, etc. I realise that is anti-climatic in a way, because I am asking you to describe a point in time without any reference to time. Which is like trying to explain the distance between two objects without reference to your typical measuremens of it.

"However, it raises the question of, "Is time really something that is ingrained into nature? Or is it something we've conceived?" The whole idea of getting you to explain a point in time with out the usually reference to its measurement was to get you to realise that if we didn't have a name and a meaning for different measurements of time, then it would be impossible to describe it. We consider a day to be the time when the sun rises to when the sun sets. Now suppose that we disregarded that as a measurement of time. What would it be then? It would simply be the sun rising and setting. It wouldn't have any meaning to us if that were the case.

"That lead's me to this: Did time only start existing when we gave it a measurement and a meaning? Before we human's came onto the scene, did time actually exist in the first place? Or is it simply a human measurement in terms of cause and effect. The number of cause and effect moments between two spacific events.

"For example, there are seven days in a week. In other words, seven cause and effect moments equals a week--the cause and effect moment being regarded as the rising and setting of the sun (a temporally time assymetric sequence). But what was the value of this 'week' before we came along and gave it meaning? That's right, a week meant nothing until we made it mean something.

"So does time really exist?"

Taking into account my analogy of the human on earth and the alien on mars, this question is quite a valid one. Even dispite the fact that you have evidence of the cosmological and thermodynamical arrow of time we still give meaning to events, and we still use our own measurements. If we didn't give it meaning or measurements, these arrows would just be objects following natural law, and doing what they are capable of doing. Instead, we look at one event, and then at another event, and we determine that time has elapsed between them, given measurements that have meaning to us. So, in effect, I should really go back to my Universe article and change it. Which I have.

I want to make this one point, however. I will argue that time is not an intrinsic property of the universe. It is not a stand alone element. It is a characteristic of physical processes and only has meaning at a relative sense. So, what I'm saying is, for now, let's not simply say that time doesn't exist. It may not be an intrinsic property of the universe, but it is a very useful tool to have. When I say 'time', think of it in terms of physical processes as opposed to a stand alone object.