∆ Our first ideas of Time.

A brief history of the notion of time.

To explain how ‘time’ can be seen to be nothing other than a human notion with no other counterpart in reality at all, we have to be clear about what we mean by a ‘notion’, and then explain how the ‘notion of time’ may have ended up seeming to be an apparently real and fundamental component of the fabric of the universe;

Definition of a ‘Notion’.

‘A notion? Isn’t that where fish swim?’ (L.Tobin.)

A ‘notion’ can be defined as ‘a vague idea in which some confidence is placed’, ‘a general inclusive concept’ (source trancreative ‘wordbook’ GET OXFORD DEF). And we may often have a notion about something when we don’t have actual proof that the ‘thing’ we are speculating about really exists or not, and any notion may or may not relate to a real thing and yet notions can work as ‘mental place holders’ and as such are essential tools in their own right.

We could say for example the notion of the ‘equator’ being a line that defines the meeting or separation point of the northern and southern hemispheres of the Earth is a very useful and practical idea or logical tool, yet if we went in search of the equator we would find it was not a real and ‘findable’ thing.

Similarly, although it is clear that the notion of time works very well for all of us all over the world in countless useful and practical ways, we should perhaps be absolutely certain we can clearly and simply prove that Time relates to a real and findable thing, before we take things too far, and start using the notion of time as if it is a concrete proof and example that the idea of other ‘hidden dimensions’ (as in string theory) in the universe makes physical sense. Or start thinking we can bend or stretch time (as opposed to just warping objects and the forces they create in the space they may be moving in), or even allocate large amounts of money to trying to find ways to travel or communicate through it.

Is the ‘notion of time’ only a notion?

With a thorough and open mind, and to avoid jumping to conclusions or blindly accepting unproven assumptions it makes sense to begin our search for the truth by reconsidering the notion of time from scratch from two basic points of view.

These being firstly, that the notion of ‘time’ either relates to something that does exist in the real world, in the same way that the notion of gravity is a notion but one that also relates to an invisible and mysterious but nonetheless real and tangible thing. And secondly, the idea that the notion of time is just and only, a mental idea or tool. Useful for organising our thoughts about ‘the ever changing world in which we live in’. But not a notion that also relates to a real and distinct, physical force, flow or phenomena that actually exists separately, and extra to, the simple movement of matter, or flow of energy that we constantly and directly observe.

Real time.

In considering these two possibilities firstly we might say that if ‘Time’ is not just a notion but also relates to a thing that really does exist in its own right, some existing feature of the universe that we as humans noticed or discovered, and then by careful subsequent observation and exploration now understand well enough to use and work with, then in this case Time is almost certainly something that was intrinsically created along with the universe and all its forces and laws in the moment of the big bang, or possibly time may be something even more fundamental than the matter we see around us.

If the notion of time relates to a real thing then perhaps time is something that can or must always exist, something that may have existed before the universe or anything else at all existed or even could exist. And perhaps time is itself ‘eternal’ or even ‘eternity’ and something that will or must exist even if the rest of the universe comes to some kind of an end.

Alternatively perhaps time exists but only as part and parcel of the whole universe, and although a real thing in its own right as much as possible it is also completely inseparable from the space and matter that make up the universe it is part of and operates in. In this way time would form as Einstein’s theories describe it ‘Spacetime’. But if time does exist only as an inseparable part or feature of the universe this needn’t make it any the less real because let’s face it, this is true for everything we observe in the universe, including ourselves !

If time is a real thing then any book, lecture or programme accurately explaining the laws of nature and the workings of the universe will also be legitimately covering in some way the creation, existence and nature of time, but if time is real then surely we should also at some point be able to directly prove the existence of all or at least some of its ‘uniquely unusual’ elements? Not just the observable ‘present’ but the ‘past’ and ‘future’ as well.

And if time is a real and essential ‘thing’ in the universe, and the only thing that can do the job it claims to do, we should also not be able to completely re-explain all of the features attributed to time in more simple and mundane ways.

No Time.

If however the notion of time is only a notion, just an idea that helps us understand things but that has no real, ‘physical’ counterpart or existence in the workings of the universe, then we should be able to completely explain everything we observe and attribute to the idea of time being real in other ways, and also we should be able to answer questions such as, how and why was this invalid notion unjustifiably created in the first place? And, how and why does the idea work and persist so well?’

As we shall see the answers to questions like this lie in the fact that we are surrounded by so much movement and change in our lives that we need some system to make sense of it, just as in society we are surrounded by so many people exchanging so many goods and services, that we need the notion of money to make it all work efficiently.

As living human beings we move and change a lot, and we live on a planet that is covered with plants, animals, oceans and atmosphere, all constantly changing, as the entire Earth itself rotates on its axis and orbits the sun. And all of this is coasting through a universe filled with even more matter and motion than we could ever possibly imagine;

And so we are surrounded not just by constant change, but by constant change in countless very different forms. And the idea of being able to compare all this chaotic change to one single ‘reference’ thing, something that changes smoothly and constantly, in a very simple way, makes great sense.

More directly if timelessness can be shown to explain all we observe, and time can be shown to be completely redundant then all questions about time, such as ‘what is time’, ‘how does time flow’, ‘what is the future’, ‘where is the past’, ‘can we travel through time’ and so on must be shown to be either invalid questions or shown to be completely replaceable by other valid questions that do have acceptable answers that do not rely on the language, ideas and existence of time.

Lastly, with the greatest respect, just as it is valid that if time is real then articles, lectures and programmes discussing the nature of the universe and the nature of time can be seen to be valid, if time is not real, then all such references to time as ‘being’ any ‘thing’ must be equally invalid and may need to be reinterpreted slightly from a ‘timeless’ point of view to make better sense.

The origin of the notion of time, the rotation of the Earth…

So considering the world around us from the point of view that time may or may not be real how could the notion of ‘time’ as being a real and existing thing flowing unstoppably from a real future into a real past come about in a world where all we ever actually see is the present moment?

To start exploring this let’s take a brief look at how mankind may have started thinking about time in the loosest sense and then given that the general distinctions of time are its past, present, future and the smooth and constant one way flow of something connecting these three features, we can first take a look at this ‘binding’ feature of time and how the idea of this ‘thing that flows in an invisible direction’ may have arisen.

One thing that virtually all animals and humans on Earth observe is the clear and bright sunrise, followed by the journey of the sun across the sky followed by the inevitable and unstoppable sunset.

Given the extremely repetitive and reliable nature of the suns appearances and disappearances it would make sense that the beginning of the real history of the idea or notion of time would start because early humans must have been inescapably and very directly affected by the very clear difference between the bright warm sunlight and the cold darkness the apparent motion of the sun repeatedly brought upon them and then defining these stark opposites as night and day.

From here the unchanging darkness of the night would seem to be pretty bland and indistinctive while it lasted but with the arrival of our emerging language skills the ‘day’ could be easily broken up into different distinct sections, with early civilisations and languages having their own words for ‘sunrise’, ‘midday’ and ‘sunset’. Once we had these ‘times of day’ in place we could communicate quite complex ideas between us like agreeing to meet and go hunting at sunrise, eat at midday or make a fire at sunset and so on.

Stopping time?

This kind of agreement would work fine on the Earth because of the way it spins at a rate that makes the sun seem to track across the sky in the way we are familiar with.

But if the Earth just so happened to rotate on its axis at just the right rate to make the sun seem to be in the same place in the sky constantly, then apart from the probably lethal climate and temperature differences this would produce, early humans would be stumped as to agreeing ‘what time’ they should get up, hunt or start fires. Not because the thing they thought was ‘time’ did not exist or because ‘time had stopped’, but just because there would be no clear, natural, regular, reliable marker of ‘change’ they could refer to[1].

Our first clocks.

Given that the Earth’s motion is such that the Sun does track across the sky our observation of the usefulness of the sunrise, midday and sunset, must have led humans to refine their understanding of the motion of the sun across the sky, or the passage of ‘change’, or ‘time’, by creating simple mechanisms to parallel or track this change such as ‘water clocks’.

The easiest way for early man to make a water clock, or ‘Clepsydra’ as they are also known, is to use one of the naturally formed and waterproof sacks or bags that make up the stomachs and intestines of animals slaughtered for food.

If you get a large enough bag, fill it with water and hang it somewhere so the water can drip out slowly and steadily through a small hole you may find the bag takes from sunrise to sunset to empty completely.

Because the Earth is spinning at a fairly constant rate, and the water is leaking out at a fairly constant rate by observing how full or empty the bag is, you can easily tell roughly where the sun should be in the sky even if it is completely obscured by clouds, if ¼ of the water has dripped out then the sun should be ¼ of the way through its journey from horizon to horizon and so on.

Furthermore once your water clock is running reliably, and if you understood the motion of the sun, you could even fill it at sunset and use it to model or estimate the position of the sun at night where it is completely invisible. Not because ‘it is late’ but because the Suns light is simply blocked by the physical mass of the Earth itself.

Once mankind can make this kind of fundamental intellectual leap, relating the change in one thing to the invisible change that we just know or believe to be happening elsewhere, results from using such a ‘clock’ become very mystical and intriguing. Imagine being the only person in a village, who by use of a simple ‘machine’ could tell with great accuracy not just when the last rays of sunlight will disappear below the horizon, which everyone else can also see, but after an entire night of completely disorientating darkness be able to declare just when very first specks of sunlight would actually appear but moments before it actually happened!

Better still, what if you could use your clock so as to get up in the darkness such that just as you finished getting ready to go out hunting the sun then appeared as if on your cue ! This really would be impressive, and give you an edge on other hunters.

Achieving concrete, repeatable results like this as we experimented with our early ‘water clocks’ may have been the first signs that led mankind to start thinking that we had discovered and were measuring not just motion and ‘change’ but something else, something deeper and more mysterious, something seemingly very real and although intangible something behind or driving ‘change’, something called time.

Inspired by success humans naturally try to refine any idea, and so the design of the water clock, the gradual and controlled release of something, can be made more accurate and reliable until we move on from just comparing the water clock to the sun to comparing countless other things to the water clock. How long does a storm last, how long a task takes, how many human heart beats are completed as a water clock marks out so many regular ‘drips’ and so on.

The problem with water clocks however is they are easily affected by local conditions, temperature humidity, being knocked or spilt or if the size of the hole through which the water drips changes with use etc, so addicted to exploration and invention we humans find other more and more successful ways to model or predict motion and change, or to ‘measure time’ as we might say, eventually moving on from water clocks to the more portable and self contained hourglass and so on.

However as we will explore in detail, just as observing the real and remarkable results of being able to predict things like just when the sun will rise, may have sparked our imaginations, our evermore successful search for greater and greater accuracy may have been the next step in our losing sight of the possibility that, instead of having ‘discovered a thing called time’, we were in fact just refining our ability to ‘track and compare change’.

> Bridging the past and the future.

[1] It is perfectly possible for a planet to spin such that one face of it is always facing its sun in the same way that one side of our own moon always faces the Earth. In fact depending simply on the ratio between the rate any planet ‘orbits it sun’ and ‘spins on its axis’ we can have ‘years that are longer than days’ or ‘days that are longer than years !’