What is "the fabric" of space-time?

We do not speak of the fabric of speed/distance.
Why would we treat space/time differently?"Space" according the the latest fermi lab testing is comprised of neutrinos.

I apologize in advance if I appear difficult. how can we say we understand a 4 dimensional structure or that it definitively exists? Why is it assumed that time is tied to theoretical space? I do not see spacetime to be any different than footpound.
My understanding is that "time" is a construct. So is space.
Time it would seem, is an emergent property of mass/energy/gravity
Speed affecting mass/energy/gravity affects time but speed is relative. Mass is not. Mass is mass. You cannot alter time to affect mass. Time is actually not affected. Time is a construct property of mass/energy. Rate of mass interaction,motion "Time" is a function of the quantity of mass. More mass alters it's state. All processes slow down. I do not see space as having anything to do with time or mass.Any suggestions of things to read that might help?
I wish I had the time to learn the math involved but I fear I might spend the rest of my life as others have. "Space" would be irrelevant. That is about where you are physically.Space expanding as a construct I accept. But it is a construct describing a physical phenomenon. therefore it must be a physical thing. We simply do not understand it yet.
Nothing known to man has yet to be proven non physical/massless. Mass may still be considered mass to infinity dissipation. There may be no smallest increment.Edited by Admin, : Fix quote.

"I would pick up something like Nigel Calder's Einstein's Universe, or similar."Thank you Of course it does. It is why any new idea is rejected. How many theories were there by very competent people before one guy came buy and said, hey this all describes the same thing...string theory.
Even the best people get lost in the math. They lose track of what they are actually representing with the math. The physical world is what it is. How we choose to look at it does determine what we see.I have not seen anything that claims time factually exists independent of mass.
If that would be case, places of less density, "intergalactic space"
Will experience time more rapidly in relation to dense areas.
The more mass, the more in the past in relation to less mass. How is where you are in space relevant?Do you believe there exists a massless anything? Or rather that we have yet to measure it's minute mass?
Do you believe there is a fundamental anything? I doubt it.
These are fantasies many physicists and mathematicians have had.Everything is made of something. As I suspect space is. "Empty" space does not exist. Empty is the issue. Space exists.I suppose I should shut up and seek your suggested reading material.