[ 27/Jan/21 – Facebook – Foundations of Logic – Walter Kant asked – The dualistic doctrine says: there is the difference between reality and its appearance;
and my question is:
How far can reality be from its appearance if this appearance has 4D dimensions (spacetime) with causalities?
1/ Reality, like its appearance, is in 4D dimensions with causalities
2/ reality is transcendent to its appearance (outside of this appearance?)]
For me, the evidence is overwhelming that reality is more complex than the computational systems of my brain can possibly deal with in detail, so evolution has demanded that the subconscious systems of brain produce a simplistic predictive model of reality that is all that is ever available to me to experience consciously, and from which the attention directing systems of brain bring my notice to where inputs from experience differ significantly from expected.
The degree to which significance varies with context is huge (many orders of magnitude).
The degree to which synaptic level protein systems influence context is huge.
It gets seriously complex very quickly.
1 seems to be often a useful approximation in many contexts, and reality also seems to contain multiple sources of fundamental uncertainty, and a few unknowables. Most modern physical theories use more than 4 dimensions (11 is quite common). Some approximation to causality is required, at least in a probabilistic form. So in the same sense that Newtonian mechanics is a useful enough approximation to allow a landing on the moon, then yes, but Newtonian mechanics cannot produce a working GPS system.
So in the sense that one requires at least 4 dimensions, and at least some form of probabilistic causality – then yes 1. But not in any sense “harder” than that – only in the soft sense of probabilistic causality.
Like Dirk says – at our normal scale – 3D plus time works.
When you start to look very closely, and very small scales of space and time (or the very large), then 4D is not sufficient to explain what is observed, and one needs to add extra dimensions to explain the observations.
The way we explain observations is by building mathematical models.
Sometimes the mathematics of the equations being used do in themselves suggest avenues of exploration (as in the case of positrons and antimatter) that turn out to be fruitful (and sometimes not).
What most people think of as 3D is based on a flat space of cartesian coordinates, where the internal angles of a triangle always add up to 180 degrees. What we seem to live in is a geometry where space itself is curved – like drawing a triangle on the surface of a ball. If you draw a very small triangle on a very big ball, then it will be a very close approximation to 180 degrees internally, but if you pick a point on the ball, travel in a straight line a quarter of the way around the ball, turn 90 degrees, travel a quarter of the way around again in a straight line, turn 90 degrees again then after going a quarter of the way around you end up back where you started – a triangle with internal angles 270 degrees.
We have ample evidence that the space we live in is actually curved, but the curvature is so small that you need very accurate instruments to be able to detect it.
When the curvature is itself subject to multiple distortions, then space itself can have very complex “landscapes”, and the classical 3D model fails – even as it is a reasonable approximation for most things we normally want to do on earth.
So it is very far indeed from being “only justified by mathematical models and is possible but not necessary”. It is actually necessary to explain observations made – if one has the time and interest to examine the sets of observations, and sufficient familiarity with the mathematical tools to be able to create some sort of intuitive model of what the mathematical tools represent.