GRAVITY PROBLEMS -- off topic from {Falsifying a young Universe}

RAZD, most of the stuff you've mentioned is in General Relativity.I'm going to ask you now "What do you think General Relativity says and what is it about, what is it a theory of?"You say that the idea of Dark Matter is dogmatic in physics, but surely of all the thousands of physicists trained over the past few decades, some of them would have come to the conclusion that the Dark Matter idea was wrong if the flaw was so obvious.The reason Dark Matter is accepted, is literally a combination of the Scientific Method and Occum's Razor.
It had the most observational observation, far more than alternate theories of gravity.
Also the fact is that General Relativity has withstood so much tests within Solar Systems (not just our own).
So the first thing you presume when subbing in all the Stars in a galaxy for T(u,v) and you don't get the right galaxy rotation curve isn't "General Relativity is wrong", but that perhaps there are sources of Stress-Energy we missed.So far this assumption has more evidence than an alternate theory of gravity.Thats Dark Matter.As for Dark Energy, it's already in General Relativity and isn't an epicycle in any manner.What your saying is a perfectly valid criticism when it comes to Dark Matter, but of the two options "Dark Matter" and "New theory of Gravity", the former has the most evidence and thats why we go with it.Look at the microlensing searches that ran from the 1970s (and in earnest from the 1980s) and are still running.
Most importantly those that looked at the large Magellanic cloud.

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Don't know as I've ever seen a good explanation of what makes a surface seem to be a surface.

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Do you mean what makes it look solid or what makes it solid?For the former things look solid or continous when there is enough individual particles in a certain area to give the illusion of a continous surface.What makes them solid is Coulomb repulsion between the outer electron shells.

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But why exactly does it do this? Why does it, and how does it follow the straightest path? How and why does it curve time and space?

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For the first question the answer comes straight from the geometry.
It follows the straightest path because unless there is a force being exerted on it, it does nothing.
And doing nothing is following the straightest possible path in spacetime.
I could explain in more detail but it would require Geodesics and (pseudo)Riemannian geometry.To the second question, General Relativity doesn't do why and how in the human sense.
It is background independant, which means that spacetime is an active participant in the physics.
Matter doesn't create gravity, any more than gravity creates matter.
In a human manner of thinking it is easier to look at it that way, but it isn't the case.It is simply "This is the Matter distribution" and "This is the geometry that goes with it".
One doesn't create the other.

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It's all well and good to say, well, it's going to go straight, unless something makes it go crooked, but why is it going in the first place? Where does that force come from, that makes it move?

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You're looking at General Relativity from a Newtonian viewpoint of abstract forces making things move.In General Relativity, Earth doesn't orbit the sun because of some force.From the point of view of somebody far away from the Solar System, the Earth goes around the sun.
This is because this observer is comparing his standard (Minkowski) time against the Earth and sees the earth move through what he calls space around the Sun from his vantage point.From Earth's vantage point it is simply existing and there is no force on it.This comes from the Earth's time being warped around the Sun by the Sun's mass, from the point of view of an external observer.
To this external observer, this warped timeline looks like a worldline around the sun.

I think it's okay.
There is a lot it skips over and there isn't any Minkowski geometry in it, so I can't rate it that highly.
It's a good layman level explanation.However, to put it one way, there is a big difference between knowing an Electric Field and Magnetic Field are connected and understanding Maxwell's Equations.cavediver might think differently.

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not really knowing at all what gravity really is!!!

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Gravitation: Wheeler, Misner, Thorne. 1973 2nd Edition.Read that book, then come back and make that statement again.

True, it is a bit on the enormous side.
(Hence the old undergrad joke of it being big enough to locally bend space itself).
And Wheeler has a very idiosyncratic way of approaching things.Biggest Physics textbook I've ever seen.
Next to Serway and Jewett, but it's a monster.

No, I haven't, although I think I will now.
I've heard others say that sometimes Penrose reads like he forgets other people don't understand his own particular way of doing things or the difficulty of it.Take a Road to Reality.
On the First page it says it is suitable for the lay reader.
By chapter 17 he is taking about what entity in the Maxwell Equations would be the Electromagentic analogue of the Weyl Tensor.It'd be one impressive lay person who could figure out all of complex analysis, Tensors, SR, GR, QM, QFT, QED, QCD, String Theory and LQG from his book just by reading carefully through the chapters.

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I don't need to read it to make that statement. Also, I don't buy the stuff about not being able to explain things unless you throw a good part of your life away!

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You don't need to read anything to make a statement, but reading usually makes statements more informed.

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Exactly why two masses separated in space have a gravitational attraction to one another remains largely unknown, despite much research

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If by "unknown", you mean "known for nearly a century", then I'd have to agree with you.

Fission and Fusion actually involves the weak nuclear force.
Most of the gained energy comes from the atom that remains after fusion requiring less "binding energy".
So the gain in energy doesn't come from converting mass to energy, but from releasing some of the potential energy associated with the force that keeps the atom together.

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Now as far as math goes, remember that after all, it is just numbers!!! You alluded to how it was good in the Lorentz-Fitzgerald contraction thing. Well, so what? It is good in the 2 + 2 = 4 thing as well. But it is pure belief to use numbers for something, say, other than a finite universe, if that was what we had. So, basically, as you get too far away, or too small, etc, all any numbers could be is an extension of your guesses! All fine and good in the box here, where they are meant to work.

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That's right, they would be guesses.
That's why we make observations.Besides a theory doesn't have to have infinite applicability to be true.
Newtonian Mechanics is still correct regardless of the fact that it doesn't apply in the Quantum Realm.

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Now as far as math goes, remember that after all, it is just numbers!!!

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That's a very naive view of mathematics(and I'm not being a Platonist).
"It's just numbers" is one of the most overused simplifications of Mathematics and Theoretical Physics I've ever encountered along with "But it's just a theory".

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Waiting to see what gravity is, since you hint you know.

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You see the main problem with this is that you're looking for a mechanism in the everyday sense.
Gravity is very well defined in physics and we certainly know what it is, but like a lot of nature, it's character is mathematical.
Any "word" description will be lacking something, no matter how hard somebody tries.
Tensors, metrics, Manifolds, e.t.c. are the fundamental ideas which express gravity, not any linguistic term.

What do you mean?
"Maths is all in the mind, if it goes beyond the physical universe?"
When do we use Math to go beyond the physical universe?Math can express what gravity is and how it works.
Whether there is a spiritual universe or not doesn't effect this. I can't explain it in English because English isn't suited to it, just like I can't express a poem in mathematics. Look, Physics is expressed in terms of mathematics, this mathematical framework called physics has experimental predicitons.
The important frameworks like General Relativity (which explains gravity) have been supported by a load of observations, which match their experimental predictions.

There is a load of corroborating evidence for Dark Matter, this is why it is considered the leading explanation.
Take the large Magellanic clouds searches, as I mentioned earlier.

The Galactic Rotation curves are what gave rise to the Dark Matter hypothesis.
The hypothesis itself has observational evidence outside of that.
Like the Large Magellanic Cloud observations. No, most Dark Matter involves MACHOS, which are definitely within Galactic space.

No, it isn't.
If that was all the evidence nobody would support it.
Look at the lensing searches that ran from 1978-1996 and then from 1998-present.
(Although the first didn't really get going until 1983.) There is a prediction which was validated.
Again, look at the lensing searches.
And there is other evidence outside that.And,.....
(1)MACHOs are not hypothetical particles, they're baryonic,
(2)not for hypothetical mass, but baryonic mass,
(3)It isn't a mathematical anomaly.

I should have been clearer.
What I mean is that most of the Dark Matter that is searched for and found is within galactic space and most of this is M.A.C.H.O.s.Most of the rest of Dark Matter doesn't have a definite distribution associated with it.One thing I should point out that it is only Dark Matter that is a hypothesis to explain observational anomalies.
Dark Energy is already contained within our theories, so it isn't really something which goes against them.
The only reason the accelerating Universe came as a suprise was because lambda was always set to zero in General Relativity as an assumption.Of course I'm not even beginning to get into Dark Energy and Inflation, which seem to be unrelated sometimes, but probably are.