"A person running (relativistically) with a ladder longer than a barn appears to a stationary observer to be completely in the barn at one point in time (even though the ladder won't fit and the runner doesn't see this odd effect) the reason is that the light from the ladder leaving the barn does not arrive until after the light from the ladder finishing entering the barn arrives (because the light moves finitely and is on the same order of magnitude as the velocity of the runner). This is a result of time dilation and the phenomenon is called length contraction (they are a pair). If the proper corrections are made, the time dilation is removed and the order of the events fixes itself. The ladder is then realized to protruded from the barn before the whole thing was inside. However, time dilation would cause an observer to say otherwise."

Now, there is the crux for me

Either it is a illusion, then you must be right, or it is not a illusion, then there come to be a moment where the pole in fact, as defined from the stationary observer, is inside the barn without 'sticking out'. If the later is true my idea makes sense. With it only being geometrics, as described by light propagating described differently from two different positional systems in SpaceTime, the observer and then from the 'event' itself, I will have to change my reasoning. Myself I see it as there actually is a moment, from the stationary observer point of view, where the pole will 'fit' inside the barn. Not looking at it that way seem to make a Lorentz contraction into a illusionary event?

==

If I assume it would be a matter of geometrics, presented to us by light, then we would have to assume that the muon would be 'time dilated', from its own view as well as from our observer on Earth. that one becomes tricky as we then can't have two uniformly moving observers both observing the other clock ticking slower than its own, as I think of it?

Alternatively you might then want to blame it all on lights 'geometrics' assuming your arrow to be the illusion. But we have the example with two 'light clocks' placed 90 degrees to each other |_ they will not be synchronized from the far observers frame, but will from the observer 'at rest' relative them. And the reason that they still are able to have the same 'time dilation' is, as far as I remember, the vertical light clocks Lorentz contraction, correcting its photons 'distance' as it bounces.

==

What I mean by that is that if you assume a 'time dilation' to be real, as defined by the twin experiment' but assume a Lorentz contraction to be a 'geometric effect' due to lights unvarying propagation, as seen from and in all frames of reference, then there is only one effect left for the muon, or for anything under the influence of motion, relative some other frame of reference? And to then assume that this effect still would be non-existing inside his frame, maybe? It's a possibility. As I said I'm not sure of how to see that, but why would the universe bother with giving us two definitions for one thing?

If we use light clocks for defining a time dilation the assumption is that as seen from any moving frame, the clock will tick 'as always'. If using the argument that the 'photon' bounces through more 'space' the faster you move is correct, then that bouncing should be slowed down inside the moving frame too. As I said, it's a possibility, assuming everything ultimately being 'light', we too then could be assumed to 'jiggle' to the same drummer as our 'bouncing photon' does. That as we too are 'passing' that same 'stretch of space' in our motion

But doing so, and still accepting an 'expansion' outside matter (galaxies), the reason that they don't expand being defined as them being of a higher gravity, seems to clash a little? Then, if that would be correct, you should expect yourself to 'expand' too, as soon as you leave the galaxy it seems?

As we then can't expect our body's invariant mass to present any problem for 'space' to permeate us, as both concepts discuss 'distance'? On the other hand, the light clock example is not perfect I think, even though it has to be near truth.

==

Maybe one can consider it conceptually, finding no definition of 'times arrow' in any positional system more true than any other? But to do so I first will have to invalidate the arrow that brought me to this point from where I consider the question it seems

As I then are questioning my own arrow too? I can do that, but doing so there will be no time dilation, as I understand the concept, and no Lorentz contraction either. The twin experiment will then be purely illusionary, no matter the biological difference between our twins, which leaves me a even weirder universe

Alternatively look at it as a sliding system, but then you still will have to ask yourself why we don't notice our 'arrow of time' slowing down when in motion? That it doesn't either way you look at it points to there being a 'gold standard' it seems to me? Can you see what I mean? That even though using 'distance' as a argument for 'times arrow' slowing down your measurements will be the exact same inside your black box, except in a acceleration which should create a gravitational blue-shift as observed from the 'gravity well' (Aft wall of your black box relative its acceleration), watching 'in falling' light.