[geordief (OP)]

Is it possible to say that the expanding/evolving universe creates "space"  as a function of itself but that it expands "into" nothingness?

Also (separately but because these two thoughts occurred to me around the same time) is it possible for two objects to assimilate and become one object (I understand "objects" may be embedded in and part of  the various fields)?

[Halc]

Is it possible to say that the expanding/evolving universe creates "space"  as a function of itself but that it expands "into" nothingness?

I suppose that one can say that expansion is the creation of a larger quantity of space from a given smaller quantity of it.  There is nothing "into" (quotes or otherwise) that space is expanding.  If there was, that would already be space, but just empty.
Vacuum (from the title, being not mentioned in the OP) seems to be a region with zero matter or possibly zero energy density.  Sure, light can be detected from anywhere, but that requires a detector there.  I am of the personal opinion that light doesn't change the state of what otherwise is vacuum.  Such a statement would seem to be a counterfactual one, and I decline the principle of counterfactual definiteness.

Also (separately but because these two thoughts occurred to me around the same time) is it possible for two objects to assimilate and become one object (I understand "objects" may be embedded in and part of  the various fields)?

That all depends on one's definition of 'object'.  The word seems to be an abstract one with no physical meaning.  It simply means this collection of <whatever> being considered/treated as a unit.

[geordief (OP)]

That all depends on one's definition of 'object'.  The word seems to be an abstract one with no physical meaning.  It simply means this collection of <whatever> being considered/treated as a unit

Probably how I was using it ..It seems like a "one size fits all" description. A Field might also be an object , I suppose(and everything is part of the Field(s) isn't it?

So Fields do merge don't they and particles might be "one object" if they are all excitations of the one (combination of) Fields

.Hope I am not talking gibbonish ;-)

btw My last (unanswered thread) was "Does the Universe expand into itself?"

[Colin2B]

A Field might also be an object , I suppose(and everything is part of the Field(s) isn't it?

A field can be treated as an object, but only as a convenient reference term, shorthand, etc. In reality it is a set of measurements/values at a location in spacetime - we’ve been through what fields are in other threads.

So Fields do merge don't they

Could you give me an example?

and particles might be "one object" if they are all excitations of the one (combination of) Fields

You’ve said particles (plural) might be ‘one object’ (singular). I’m not at all sure what you are asking.

.Hope I am not talking gibbonish ;-)

btw My last (unanswered thread) was "Does the Universe expand into itself?"

Looking at that question, you’ve thrown a lot of ‘bits’ into the OP. That probably put folks off answering as they weren’t sure what you were asking.
You’ve done the same in this OP. Rather than ask the title question you’ve actually asked 2 other very different questions, so we are up to 3 at once. Not easy to answer succinctly, and makes for a confusing thread.

As to your title question, quick answers:
Space, other than being the final frontier, is a set of 3 dimensions.
Vacuum can be: the common use meaning no air; QM use meaning lowest possible energy which means no particles inc photons; GR stress energy tensor is zero, hence no momentum, energy, fields etc. Basically, nothing there.

[alancalverd]

Space is what is between objects. The definition depends on the objects and the context. The space between pebbles can be empty, or filled with air, or filled with sand.

The space between planets is mostly filled with nothing at all, with a few particles and molecules drifting about.

We can only make statements about the observable universe because its radius is limited by all the physics we know. There may be stuff or nothing outside, but as far as we know it has no effect on us because the observable universe appears to be expanding faster than any information from outside can reach us.

[geordief (OP)]

Could you give me an example?

Well some have said that a Field is a set of measurements but others have said "no a Field is a thing in its own right".
From my lowly position in this "field" of knowledge ,I am not in a position to adjudicate.

However , in my question which you have addressed I accept I was treating Fields as objects in their own right.

So ,to give you the example I had(based on that possibly flawed understanding) it would go like this;

Suppose we have a charge in one location then it will have its own Electric Field .
Now ,if we have another separate  charge  it will also have its own Electric Field.
These two electric Fields will (per my understanding) interact with each other  and it will be  (again as I anticipate) possible to view the two separate Fields as one "conglomerate"

Any particles associated with this "combination Field" can (again in my possibly very flawed understanding) be attributed to either Field of both (actually,I would guess to both.)

Extrapolate to all the Electric Fields in the Universe and we have one Electric Field (to rule over all ;-)  )

I took the Electric Field as an example. I assume the same might apply to any of the other kinds of Fields there are ...

Now that is what I had in mind (you did ask)

I hope not to be too embarrassed by your reply

Oh and thanks for looking at the other thread I mentioned.

[kr236rk]

Space is just that - 'space' - there is no word to describe it, emptiness.

[jeffreyH]

Fields have a source. These are particles for electromagnetic and gravitational fields. My question is what is the source of the Highs field?

[Colin2B]

Well some have said that a Field is a set of measurements but others have said "no a Field is a thing in its own right".

The first is the correct definition, the second is treating it as an object.
A lot of this has to do with terminology and use of words as shortcuts for more complex sentences. With many types of field eg temperature field in a room, we can identify an underlying cause eg warm air, when we get to many of the QM/QFT fields we can’t see below them, at the moment they ‘just are’ hence we treat it as an object, a thing it it’s own right - easier than always having to say “field x which is a set of measurements but we don’t yet have an underlying cause”. (Takes deep breath).

Suppose we have a charge in one location then it will have its own Electric Field .
Now ,if we have another separate  charge  it will also have its own Electric Field.
These two electric Fields will (per my understanding) interact with each other  and it will be  (again as I anticipate) possible to view the two separate Fields as one "conglomerate"

Again this is a terminology issue.
We refer to particles having an electric field, and yes we refer to each one as having its own field, but their fields are only disturbances (variations of measured intensity at a point) of the same electric field. Imagine 2 loudspeaker in a room, each generates its own disturbance of the air in the room (which you can measure if you only switch on one at a time) but it is the same air in the room they are both disturbing.

[evan_au]

Is "Space" distinct from "nothingness"? (and the Vacuum)

My attempt:
A vacuum is when you have removed all the baryonic matter from a volume of space.
- You have to work very hard to ge a "good" vacuum, as atoms are always boiling off the container walls and seals.

If you really want nothing, you would need to remove light (not entirely possible above absolute zero), neutrinos (not possible with any shielding we can imagine), and Dark Matter (we don't even know what it is, let alone imagine a way to keep it out).

[geordief (OP)]

Is "Space" distinct from "nothingness"? (and the Vacuum)

My attempt:
A vacuum is when you have removed all the baryonic matter from a volume of space.
- You have to work very hard to ge a "good" vacuum, as atoms are always boiling off the container walls and seals.

If you really want nothing, you would need to remove light (not entirely possible above absolute zero), neutrinos (not possible with any shielding we can imagine), and Dark Matter (we don't even know what it is, let alone imagine a way to keep it out).

OK so are we better just (re)starting from the position that a vacuum is not only impractical to create but that it is a misnomer  and that we can only really talk about relative densities of whatever we are considering?

My first introduction to this idea of a vacuum was the "Nature abhors a vacuum"  saying which made such perfect sense to me at the time.(with its seeming relevance  to both physical and political events)

Time to cast "vacuums" into the bin of history?

"Nothingness" is clearly also a contentious subject (I think Odysseus  got the better of one of his opponents with his "My name is  Nobody "   repartee).

I don't think we need to pick at that scab for now ;-)

[kr236rk]

'Nothing' does not exist, because liminal matter constantly appears and disappears in the vacuum of space - does it not - causing the universe to expand?

[Colin2B]

OK so are we better just (re)starting from the position that a vacuum is not only impractical to create but that it is a misnomer  and that we can only really talk about relative densities of whatever we are considering?

No, just because something is unattainable doesn’t mean it couldn’t exist, or that the concept of it might not be a useful thing.
The calculation of the minimum energy in a QM vacuum is a useful tool.

liminal matter constantly appears and disappears in the vacuum of space - does it not - causing the universe to expand?

No it doesn’t, see  https://www.physicsforums.com/insights/vacuum-fluctuation-myth/

[kr236rk]

The emphasis of your negation belies Heisenberg's uncertainty principle I feel.

[Colin2B]

The emphasis of your negation belies Heisenberg's uncertainty principle I feel.

The uncertainty principle says that we cannot measure the position (x) and the momentum (p) of a particle with absolute precision, the more accurately we know one of these values, the less accurately we know the other.
Nothing to do with particles popping in an out of existence.
Did you read the article?

[kr236rk]

The emphasis of your negation belies Heisenberg's uncertainty principle I feel.

The uncertainty principle says that we cannot measure the position (x) and the momentum (p) of a particle with absolute precision, the more accurately we know one of these values, the less accurately we know the other.
Nothing to do with particles popping in an out of existence.
Did you read the article?

Yes, I am afraid it is beyond me. But the 'virtual particle' is a theory, I don't see that it can be proved or disproved beyond laboratory conditions, with all due respects to Mr Arnold Neumaier.

Reference https://www.physicsforums.com/insights/vacuum-fluctuation-myth/ [nofollow]

[Colin2B]

Yes, I am afraid it is beyond me. But the 'virtual particle' is a theory, I don't see that it can be proved or disproved beyond laboratory conditions, with all due respects to Mr Arnold Neumaier.

Virtual particles are not a theory, they are representations of mathematical models of internal processes in QM. Prof Neumaier has done a lot of work on the maths of QM and is keen to dispel some of the misunderstandings that arise due to poor interpretation of the maths and concepts.
Examples abound. There is one poor soul in new theories who is completely confused by his misunderstanding of observation, measurement, wave/particle duality, matter waves etc; such that he is unable to understand some very simple concepts.

[kr236rk]

Virtual particles are not a theory...

The word 'theory' is used half a dozen times in that article, and a model is just a model & remains so until it can be proven or disproven & then discarded I feel.

[Colin2B]

The word 'theory' is used half a dozen times in that article, and a model is just a model & remains so until it can be proven or disproven & then discarded I feel.

But have you really read and understood what the article is saying?

[kr236rk]

Have I read the article? Please refer to post 16. You stated:

Virtual particles are not a theory...

However, I believe you are in error because a virtual particle is a transient quantum fluctuation that exhibits some of the characteristics of an ordinary particle, while having its existence limited by the uncertainty principle. The concept of virtual particles arises in perturbation *theory* of quantum field *theory*. Virtual particles are therefore *theoretical*, as is quantum field *theory*. I rest my case.