Originally posted by sir Mojo Loren
Geometry is a mental construct. It is mathematical and has no existence apart from the mind wrt the measured object which is made out of substance.
Really? So a train is not larger than a car unless it is measured? Is the distance between galaxies any less real if there are no humans to measure it? Of course not. As you've also pointed out, a dimensionless physical object is an absurdity.
Can you not see the abstractness of this statement? How can curvature have any meaning without something to be curved?
The space is curved. And as I said, our concept of space does not relate to any abstraction, at least not in the context of the word being used here.
Einstein recognized this when he said the ether was absolutely essential to understand this concept. [ note: space is not a substitute for substance. If you claim that it is then there is no sense in the distinction and the words have identical meaning.
Please don't misrepresent what Einstein said. He did not claim that any fluid like substance at all was necessary. Nor is any substance at all required, according to him. The gravitational field, is a very different kind of aether, as it has properties (a metric, energy, curvature and such) that make it a "thing" in the ontological sense. In other words, it's necessary to have a concept of a gravitational field that is dynamic and not the flat, lifeless void of the past. But it is not "made of" anything, especially a fluid like substance. Einstein wrote a lot about that, and never supported such a notion.
Not even close...that is mathematics in motion.
Nope, because geometry is an applied branch of mathematics. While you can have all kinds of abstract mathematical situations that don't apply to anything concrete, geometry is specifically the study of
space, which is a very real property of things. And the thing is, any physical event in the universe (a colliding galaxy, exploding star, etc.)
can be moduled entirely in terms of evolving geometry. Logically, you do not need to make matter any substance to have all physical situations defined in a way.
Your satisfaction at the mathematical level of abstraction is why this conversation is not getting anywhere. Have you studied metaphysics? If you had you should understand the crucial distinction between mathematics and causality that you are blurring.
Yes I have, and would not be making these claims if I didn't find it impossible to justify the need for substances. I used to think that substance is what gives rise to volumes, and without it, space could not exist. Then when I failed to actually find any properties to define such a substance that weren't already contingent upon space in the first place, I realized it was backwards. Instead of substances giving rise to space, space gives rise the our perceptions of substances. The logic of this is unavoidable.
What can a node or a lattice mean without being made out of something?
That becomes quite obvious when you realize that something fundemental,
by definition cannot be made or comprised of something else! It would be like asking what the fluid substance that defines the aether is made of. If it is fundemental, it is not made of anything. And this is really a logical necessity, because if something is made of something else, it cannot be fundemental, again by definition.
Physics has declared that mathematics is what reality is made out of. You have the masses on your side, but I am afraid they have abandoned reason and thus they do not understand the necessity of causality--they are blind to the physical reality that the equations quantify.
You are again mistaking abstract mathematics, with geometry which is the study of space.
You are confusing continuous with homogenous. They are not equivalent. Continuous simply means that there is no absolute division or gap anywhere in the substance. If this substance were homogenous then nothing tangible or perceptible (including perception itself) would exist.
My point is that if something is a continuous medium, and not made of composite parts in some kind of relational structure, I don't know where there is any room for inhomogenous regions. Why different regions can have different properties at all is the question, and goes back to Newton as I mentioned. You can put all kinds of labels such as density on them, but all you will have is a label. You won't have any other way of telling apart different regions. With GR, you can see that a compressed volume of space is different from an empty space, because density=more curvature.
Matter in motion works just fine. It does not need to be made out of extensionless particles in a void. Such a concept is pure nonsense.
Quantum theory does not suggest that either, as it is about fields as well. And as I said, matter in motion can easily be defined as geometry in motion.
In actuality there is no such thing as an absolutely empty region of space. What you percieve as "emptyness" is merely the lack of something perceptible, specific or understood.
You can also say there is no such thing as "full" space either, only different conditions of the same thing. In GR, that condition is geometry. Either approach ends up with the same result.
Absolutely correct, but I was talking about the theory of General Relativity and not the reality which it abstractly measures.
It's not abstract, it's space.
Size is relative to the measurement system employed and extension is a fundamental property of substance so an extensionless point of substance is an absurdity. This simply illustrates the vast difference between metaphysics and mathematics.
A fundemental property is one that cannot be taken away without losing the identity of the "thing" in question. Since an extensionless aether is not possible, volume is then a fundemental property of the aether. If that's true, you logically cannot have an aether without volume. However, you
can logically have a volume without the few additional properties the aether has. Therefore, the aether is just a volume with additional properties tacked on.
Just because they are about the physical world does not mean that they contain a coherent metaphysics (beyond physics). In fact they have abandoned the fundamental concept of metaphysics and that is causality itself.
I thought we were on the same metaphysical page here, namely physicalism/materialism? In such case any physical model of the universe will necessarily touch on metaphysics for a materialist. There is nothing logically inconsistent or inconherent about a universe based on the findings of field theories. The claim that causality is abandoned is completely false, since no classic theory like GR is complete without it. And as I said, matter can be defined as spaces without logical inconsistencies or the need for a fluid like substance.
False. The theory is just unknown.
That's along the same lines as what I said. A theory has not been found yet. Oddly enough though, unification is not the big problem. Supergravity can unifiy all the forces and matter, for example. The problem seems to be the uncertain language that QM speaks.
It doesn't even consist of a material, how can it have anything deeply meaningful to say about materialism?
It says everything material IS fundementally space and time. Think about it. Everything we perceive in the physical world is involves space and time. That is, a spatial object that is constantly evolving. Spacetime seems to be the only way to define physicalism at all, and you don't need substances to do it.
Again you are confusing metaphysics with mathematics. I suggest you read some Spinoza for the best source on metaphysics. Einstein himself said he was a disciple of Spinoza, so maybe this will help you understand why he said the ether was absolutely essential to understand "curved space".
As I said, Einstein did not believe in substances either. In terms of metaphysics, an aether is just a space with additional properties. While you can define a space without the need for substances, you cannot give any meaning to notion of substances without space.
