Is Space a Concept?

[Syne]

Gravity is an acceleration that produces potential energy.

[C C]

Is space a concept?

If "abstract ideas" and useful principles are restricted to what is formulated and mediated by the verbal and written symbols of non-pictorial thought processes, and it's taken that the most elemental ones which more complex ideas are built from originally had to have empirical, particular phenomena for source (to be extracted or generalized from), then...

Psychological space could be construed as non-conceptual, since it's either part of or the persistent ground for the manifestations of extrospective sensation and introspective imagination. The assorted other ideas (thought and quantitative constructs) called "space" or identified / associated with the term "space" are either directly abstracted from that original psychological / physiological source or are inspirationally descended from it in a more indirect to convoluted history of disciplinary practice and intellectual activity.

Also, it may depend upon personal take on perception. Those who believe concepts and memory are necessary for any experience to arise (IOW, the latter does not outrun cognition) would of course deem manifested extension / space to be as concept-dependent as any other perceptual content. One partial exception among possibly many would be Kantians, who would take space to be an a priori intuition separate from the categories (forms of thought) -- the latter only providing interpretative discrimination and identification of objects from the affairs / appearances abiding in psychological space. "Partial" because there are places where Kant seems to indicate that full-blown phenomenal experience still relies on merger with or application of concepts, despite space not qualifying as such.

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[elte]

I'm lead to the idea that gravity can be put in the matter category, a type of matter extending between two things that have mass in the Newtonian sense.  If the graviton is taken to be the particle involved, it could be a form of matter that could be part of a relationship of potential energy between masses that exist in the Newtonian sense (not even really considering the destructive E=mc^2 aspect of potential energy that matter has).

[Secular Sanity]

I’m not entirely sure but I don’t think that general relativity is a relational theory of motion. I think that the spacetime manifold in general relativity is considered an entity.   

In physics and philosophy, a relational theory is a framework to understand reality or a physical system in such a way that the positions and other properties of objects are only meaningful relative to other objects. In a relational spacetime theory, space does not exist unless there are objects in it; nor does time exist without events. The relational view proposes that space is contained in objects and that an object represents within itself relationships to other objects. Space can be defined through the relations among the objects that it contains considering their variations through time. The alternative spatial theory is an absolute theory in which the space exists independently of any objects that can be immersed in it.

The relational point of view was advocated in physics by Gottfried Wilhelm Leibniz and Ernst Mach (in his Mach's principle). It was rejected by Isaac Newton in his successful description of classical physics. Although Albert Einstein was impressed by Mach's principle, he did not fully incorporate it into his general theory of relativity. Several attempts have been made to formulate a full Machian theory, but most physicists think that none have so far succeeded.

Relational Theory (wikipedia.org)

So, here's what I'm thinking, elte.

"Space-time does not claim existence on its own, but only as a structural quality of the field."—Einstein

A gravitational field is a direct consequence of the curvature of spacetime, and if the existence of the gravitational field is inseparably bound up with the existence of space then I would say that it can be considered a physical entity just like any other field.  

Field (physics) (wikipedia.org)

[Syne]

Too many analogies like the "rubber sheet" one for gravity give people the erroneous notion that space is a thing or fabric, when they are just demonstrating the interaction.
Fields are essentially forces. We don't call forces things.

[Secular Sanity]

Too many analogies like the "rubber sheet" one for gravity give people the erroneous notion that space is a thing or fabric, when they are just demonstrating the interaction.
Fields are essentially forces. We don't call forces things.

The EM field is considered a physical entity, isn't it?

"In the modern framework of the quantum theory of fields, even without referring to a test particle, a field occupies space, contains energy, and its presence precludes a classical "true vacuum". This led physicists to consider electromagnetic fields to be a physical entity, making the field concept a supporting paradigm of the edifice of modern physics."

"The fact that the electromagnetic field can possess momentum and energy makes that field very real, and so, for better understanding, the original idea that there are just the forces between particles has to be modified to the idea that a particle makes a field, and a field acts on another particle, and the field itself has such familiar properties as energy content and momentum, just as particles can have. To take another example: an electromagnetic field has waves, which we call light; it turns out that light also carries momentum with it, so when light impinges on an object it carries in a certain amount of momentum per second; this is equivalent to a force, because if the illuminated object is picking up a certain amount of momentum per second, its momentum is changing and the situation is exactly the same as if there were a force on it."[source]

[Magical Realist]

Fields are essentially forces. We don't call forces things.

Yes we do. Any noun is a thing. Anything that exists and has boundaries to its existence is a thing.

[Zinjanthropos]

If space & time have no physical property then what else can they be except concepts? Then again I think my thoughts belong in the same category. I think space & time are going to be whatever I think they are. So as concepts, are thoughts and space the same thing? A whole lot of nothing? Well I can't call either one of them a real thing if they are concepts or can I? 
I'm under the impression that matter is real. Is my impression a thought? If it is then what does that make matter? 

[Secular Sanity]

If space & time have no physical property then what else can they be except concepts? Then again I think my thoughts belong in the same category. I think space & time are going to be whatever I think they are. So as concepts, are thoughts and space the same thing? A whole lot of nothing? Well I can't call either one of them a real thing if they are concepts or can I? 
I'm under the impression that matter is real. Is my impression a thought? If it is then what does that make matter? 

There’s proof that frame-dragging occurs.  If rotating mass can drag spacetime with it, how could we then say that it’s simply a concept?

https://www.youtube-nocookie.com/embed/cPEwkMHRjZU

[Syne]

Too many analogies like the "rubber sheet" one for gravity give people the erroneous notion that space is a thing or fabric, when they are just demonstrating the interaction.
Fields are essentially forces. We don't call forces things.

The EM field is considered a physical entity, isn't it?

"In the modern framework of the quantum theory of fields, even without referring to a test particle, a field occupies space, contains energy, and its presence precludes a classical "true vacuum". This led physicists to consider electromagnetic fields to be a physical entity, making the field concept a supporting paradigm of the edifice of modern physics."

"The fact that the electromagnetic field can possess momentum and energy makes that field very real, and so, for better understanding, the original idea that there are just the forces between particles has to be modified to the idea that a particle makes a field, and a field acts on another particle, and the field itself has such familiar properties as energy content and momentum, just as particles can have. To take another example: an electromagnetic field has waves, which we call light; it turns out that light also carries momentum with it, so when light impinges on an object it carries in a certain amount of momentum per second; this is equivalent to a force, because if the illuminated object is picking up a certain amount of momentum per second, its momentum is changing and the situation is exactly the same as if there were a force on it."[source]

"Michael Faraday first realized the importance of a field as a physical quantity, during his investigations into magnetism. He realized that electric and magnetic fields are not only fields of force which dictate the motion of particles, but also have an independent physical reality because they carry energy."
- https://en.wikipedia.org/wiki/Field_%28p...omagnetism

Unless and until we find the graviton and can measure its energy independent of the gravitational field, we can only view gravity as a field of force, rather than a physical field. If we could explain gravity the same way we explain electromagnetism, we would have little trouble unifying them.

Fields are essentially forces. We don't call forces things.

Yes we do. Any noun is a thing. Anything that exists and has boundaries to its existence is a thing.

Scientifically ignorant semantics.

If space & time have no physical property then what else can they be except concepts? Then again I think my thoughts belong in the same category. I think space & time are going to be whatever I think they are. So as concepts, are thoughts and space the same thing? A whole lot of nothing? Well I can't call either one of them a real thing if they are concepts or can I? 
I'm under the impression that matter is real. Is my impression a thought? If it is then what does that make matter? 

Space and time are concepts defined by certain relations between things. It's the physical things that have properties that define space and time. You're thoughts are, hopefully, no where near as limited.

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There’s proof that frame-dragging occurs.  If rotating mass can drag spacetime with it, how could we then say that it’s simply a concept?

Proof that it affects physical things...not that it exists independently of things.