Time is about dates and ages, and how long until lunch, and when do you want to meet, isn’t it?
The rising sun is one of our most significant occurrences, figuratively and literally. The start of a new day is crucial to the way we live. Every day starts afresh, and we build our lives around fitting into the recurring pattern of a day. The event of the start of a new day is so intrinsic to our thinking that we simply take it for granted, and submit ourselves and our lives to this continual event-series. We expect there to be a tomorrow, and a tomorrow after that.
How would we measure time if the earth didn’t rotate i.e. if we didn’t have a regular event-series to build our lives around? If the earth’s rotation was sporadic and unpredictable, as the sun rose we would have no idea how long the day ahead would be (perhaps it often feels like that anyway).
But we would not have a constant unit of measurement around which we could build our time frame.
And if the earth didn’t spin at all, would we have any sense of time? If there was no night to mark the day, how would we think of time? Would we see it as something constantly evolving?
It’s intriguing to speculate, but we can’t really know because for us the ingraining of the day/night pattern in our psyche structures the way we live. As the man said “Day follow night follows day” – it’s time passing surely? This is the beginning of our relationship with time.
Time as an abstract framework (mental model)
We have this rhythmic event-series going on around us continually. The earth spins on its axis once every 24 hours – and not forgetting that it orbits the sun once every 365 (and a bit) days. This regular rhythmic movement of rotation and orbit allow us to construct a framework whereby we can reference very precisely any and all events. Everything can be measured or calibrated by reference to the units of years, days, hours seconds, built by reference to convenient standard event-series (e.g. the earth rotation).
“What is the time?” is one of the most commonly asked questions. What does it mean? What we want when we ask this question is for someone to index ‘now’ in a manner that is understandable to us both. The time in this instance is a commonly understood indexing reference.
The date most dear to us is probably our own birth-date – an exact point in time when we came into existence. It’s a point in time indexed by reference to a particular date (supposedly the birth of Christ) and its proximity to that date.
So we can build this elaborate framework that can index any event, any point in time, by relative relationship to other points in time – time is a referencing framework, an abstract (it only exists in this sense, in our collective minds) referencing framework to be precise, whereby we index events.
It’s worth also pointing out here that a dimension can be defined as a reference framework; so here we have time as a dimension, an abstract reference framework.
Dimension is a word that seems to me to cause many people a problem. In relation to space a dimension (so they perceive) is ‘real’ – there is an actual gap between my chair and my desk, which is space – so dimension means something real, something concrete.
I would suggest that space has two distinct definitions – that of the real gap, and that of the abstract framework that we use to calibrate the gap. Strictly speaking, the dictionary definition (again, not in my opinion, an emphatic definition) of dimension is just a measured extent of a spatial or temporal quantity.
When Einstein called time the fourth dimension, it gave time the perceived quality of being ‘real’ – i.e. a concrete thing. I think this is where much of science confusion lays. Although space does have a real meaning, it is also an abstract framework by which we measure, index and reference occurrences and gaps between occurrences (i.e. distances). And for time to be asserted as having the same concrete existence as space because of this is use of ‘dimension’ is simply unproven, unsatisfactory and unnecessary though unfortunately universally accepted. We come back to this distinction later; it is an important stumbling block.
So really, our abstract framework is complex – it includes space-time and the joys of Einsteins relativity – a mathematical abstract – but an abstract framework nonetheless.
Units of Time
From this framework of the earth’s motion we have constructed units of time; years, hours, days, minutes seconds and so on.
It’s worth bearing in mind that in fact these units of time are actually units of change; they are based upon regular event-series – the constant stream of [quantum] events that is the earth’s continual motion.