# This is an email I sent to about 20 leading scientists who have all put vidoes on You Tube on the subject of Time ..and who all fail, continually, to explain time in any meaningful way.

Hi. This is a humble plea. You are all academics or writers who write/vlog on the subject of Time and Space. All of you brandish these significant words with great aplomb. Yet these two words both have multiple meanings depending on context. With the greatest respect, none of you ever secure their context and definition before you use them…causing confusion, I suspect.  And, if you don’t mind me saying, also often seem to ignore the only empirical evidence we have of ‘Time passing’…that is change/change-events.

Let me be bold:-

·        Again with respect, a small reminder – a dimension is an abstract framework for calibrating and indexing a specific objective property or attribute – the underling reality. Abstracts only exist in our collective minds. As an example, temperature is a dimension – the dimension of heat. Temperature calibrates and indexes the underlying objective reality of heat.  So temperature is abstract; heat is the underlying reality. Dimensions must have a singular underlying objective reality to which they refer, else they ain’t dimensions, just maths.

·        Time (in this context – see A. below) is the dimension of change. Time is abstract; change is the underlying reality. (i.e. time is how we calibrate ‘rate’, obviously).

·        Space (in this context – see B. below)) is the dimension of (static) position. (Static because, by definition, it excludes time.) Space (in this context) is abstract; position is the underlying reality.

·        Spacetime, hence, is the dimension of motion (i.e. ‘changing position’ – the clue is in the name). Spacetime is abstract; motion is the underlying reality.

·        [Space and time are simple, single reference-frame dimensions, hence linear in scope. Space-time is a complex compound dimension, and adds higher dimension with changing motion i.e. acceleration (‘spacetime-time’ maybe) and changing acceleration (spacetime-time-time) etc. Hence non-linear].

We don’t ‘move’ in time. Move is a spatial reference. We change in time. [Like we don’t ‘move’ in the dimension of temperature, we cool-down or warm -up etc]. Please don’t use spatial references for other dimensions. Maybe Einstein confused us all a bit by implying time was sort of a spatial dimension? Really, we know it’s not.

A.     On time specifically – where the biggest struggles seem to occur – the word time has two core, distinct meanings. An assertion, the ONLY empirical evidence we have for Time ‘passing’ is change (events). Ask Aristotle. Or just look around you. From the first change-event (the Big Bang?) there have been, (and are, and will be to come), zillions of subsequent quantum (and compound) change-events. 1. We attribute the word time to both the dimension [that we use to calibrate and index change]; 2. and we use the same word, time, as a non-specific collective term to aggregate change – the ‘flow’ of change (i.e. time is to change what traffic is to vehicles – a non-specific collective noun – time and traffic are both said to ‘flow’, even though collective nouns are abstract). There is no other evidence of times ‘nature’ than the zillions of quantum and compound change events happening all around us. Time (in this context) is a collective, the ‘flow’ of change. ‘Time passing’ is really change ‘flowing’ i.e. happening.

So, time has two distinct core contexts/meanings (both abstract). The dimension (of change) and the flow (of change). Yet it is only ever spoken of in a vague, ill-defined way. Which do you mean? [And some of you even infer time is somehow tangible or ‘real’ – where is your evidence please?]

B.     And, as mentioned, space is obviously the dimension of position (ergo length, breadth, height). Though the word space also has other contexts and meanings (not that you often differentiate…you should; for example, do you mean a non-specific subset of the universe? A gap? Not Earth?) There seems to be a space in our definition and understanding here.

A few other observations come from this:-

·        Position, change and motion are the reality; Space (in this context), time and spacetime are the abstracts. Often people conflate objective reality and abstracts when hypothesising (i.e. see arrow of time below).

·        It is worth remembering that position and change are [reference frame or quantum] specific. NOT universal. i.e. there is not a universal time ‘thing’. There is individual change, which is specific. Yes, space and time (in this context) are universal dimensions / calibrations (like temperature is), but they are abstract, and apply reference frame specifically, not universally.  This is a crucial distinction.

·        Time-dilation is not the warping of time…you can’t warp an abstract. Time is simple, reference frame specific, and linear. Einstein showed that it is (relative) motion that does the ‘warping’ – spacetime is complex and non-linear (see above).

·        The arrow of time? Really? The arrow (‘direction’) must belong not to the abstract, but to the underlying objective reality…the arrow of change? But there are hence zillions of them, for these arrows are reference-frame (or quantum) specific, NOT universal like the ‘arrow of time’ would infer. One arrow of change for each quantum change event? That is a lot of arrows. (Remember, entropy is about change [all change is caused by energy differential], it’s not about time; time just calibrates it).

·        The Block universe theory…really? Time infers change. The past has changed to become the present, which changes again to be the future. That is why they don’t all exists together.

·        Do you have a ‘profound experience’ (as one of you describe) of time, or do you have a profound experience of CHANGE? I know what I experience.

So, respectfully, that’s my tuppence worth. Disagree with me, by all means. But, please, I do just wish we might all apply some fundamental academic rigour in this particularly slippery subject:

1. Define your terms and context precisely (particularly the words Space, Time and Dimension),

2. Secure what objective empirical evidence we have (Position, Change, Motion) and differentiate reality from abstract concepts, they need to be treated separately. [‘What’s reality’ I hear you cry…I define it as anything that doesn’t only exist in our collective minds.]

Please, if you consider these two principles, then we might all save Time…

I sincerely hope this helps,

# Why is time regarded as an extra dimension if it is just an effect (or property/attribute) of 3-dimensional space?

Time isn’t an effect, property or attribute of ‘3-dimensional space’. They are 2 distinct, separate dimensions.

Time is the dimension of change (hence ‘rate’…eg miles per hour…the per hour bit is time calibrating change.)

Space (in this context) is the dimension of (relative) position (hence xyz-axis). In fact, Space is the dimension of static position (because, by definition, it excludes Time).

Merge the dimension of static relative position (Space) with the dimension of change, and hey presto you get Spacetime, the dimension of changing position…aka Motion.

That makes Time a pretty important dimension in its own right. Change is what drives the universe, after all.

I am going to link below to an answer I just posted to a similar question.

I hope this helps…

https://qr.ae/pG60xJ

https://qr.ae/pG603s

# If the fourth dimension is time, does that mean we are constantly moving in the fourth dimension?

No. Time is not a spatial dimension (Space is!). ‘ To ‘Move’ is a spatial reference.

Time is the dimension of change.

We are constantly changing in the fourth dimension.

https://qr.ae/pGzk3l

# What is time? Does it really exist? Or is it something that humans made up to keep track of their deeds and lifespan?

It’s just as you say.

Let me explain…

The ONLY empirical evidence of Time is change / change events (look around you – earth spinning, you breathing, quarks decaying – all change event series).

Time represents TWO distinct contexts of change:

1.The dimension of change, i.e. an abstract framework composed of standard units that allow us to calibrate and index change and events. i.e. Time is to change what temperature is to heat, a dimension/calibration set. Temperature is abstract, heat is real, Time is abstract, change is real; and

2. Time is the collective ‘flow’ of change. Time is to change-events what ‘River’ is to water molecules – a collective term. But, fundamentally the word River is an abstract collective of water molecules which are real. Time is a collective abstract, a collective of change-events, which are real – Time, the ‘flow’ of change.

Time, one word, two distinct meaning, both reference change.

And both are abstracts…Time is made up by humans, as you say.

https://qr.ae/pGq662