What warps space?

[hoola]

if gravity expression is due to a warpage of space, what is doing the warping? In space is a sea of virtual particles, I conjecture that the geometric orbits of these annialations are affected by proximate energy/matter, thus extending the annialation process resulting in the observable effect of gravitation. This local change of annialation process expands out in a phononic-like manner at c with the inverse square law with tensor expression into the surrounding sea of VPs, thus inferring then stiff, yet deformable flux being the observable result of what we call space.

Edited May 28, 2017 by hoola

[studiot]

Space is not warped.

It follows its true and proper form.

 

The very statement 'warps space' implies there is some unwarped absolute coordinate system to compare against.

 

You will struggle with Relativity until you can abandon the idea of absolute space or absolute time.

 

Draw a circle or part of one.

 

What warps the line you are drawing?

It is not a straight line - would that be somehow preferable?

 

Is the circle a warped straight line and is the straightline absolutely perfect?

 

Or is the circle correct for a circle?

[Mordred]

Or thinking of space as some form of material will also get you into trouble.

 

What curves spacetime ( not space) spacetime being a metric system with time treated as a coordinate is the energy/momentum stress tensor.

 

A key note "heuristic explanations" of complex relations will get you into trouble every time unless you take the time to understand the math behind those heuristic explanations. It is a specific set of relations that curve. The specific set of relations being freefall motion itself.

Edited May 28, 2017 by Mordred

[hoola]

so spacetime warps, but not space? .

Edited May 28, 2017 by hoola

[geordief]

so spacetime warps, but not space? .

Subject to contradiction or correction it is the spacetime model which is warped(I think the word "curved" may be preferred) -not some "physical" entity called "spacetime" .

 

The model allows one to predict events -it fails to do so in certain situations such as "singularities" (eg in black holes).

 

Space (in the model) seems to me to be a 3D subset of 4D spacetime but I am not entirely clear about this (or how useful a concept it is if true)

[MigL]

Absolutely.

The best theory we have for gravity, GR, models it as a warping ( or curvature if you will ) of the 4 dimensional co-ordinate system ( or metric if you will ).

Does space-time ( if that exists other than as a mathematical concept ) actually warp or curve ?

No-one knows., and very few people care.

As this model allows us to make extremely accurate predictions in the circumstances where it is valid.

[StringJunky]

Absolutely.

The best theory we have for gravity, GR, models it as a warping ( or curvature if you will ) of the 4 dimensional co-ordinate system ( or metric if you will ).

Does space-time ( if that exists other than as a mathematical concept ) actually warp or curve ?

No-one knows., and very few people care.

As this model allows us to make extremely accurate predictions in the circumstances where it is valid.

It seems to me, everything, be it spacetime, radiation or particles, distils down to abstractions. The ontological nature of spacetime is no more or less difficult to understand than particle or radiation fields; they all deal with values distributed in a co-ordinate system. I should say, that's probably as 'ontological' as it can get,

Edited May 29, 2017 by StringJunky

[mistermack]

Space is not warped.

It follows its true and proper form.

 

The very statement 'warps space' implies there is some unwarped absolute coordinate system to compare against.

 

You will struggle with Relativity until you can abandon the idea of absolute space or absolute time.

 

Isn't warping a comparative thing? At it's maximum near a black hole, and at it's minimum at a point at maximum distance from a gravity source?

 

So while you can't point to any area of non-warped absolute space and time, can't you point to somewhere that approximates to it, and infer what non-warped space time would be like?

[studiot]

 

Isn't warping a comparative thing? At it's maximum near a black hole, and at it's minimum at a point at maximum distance from a gravity source?

 

So while you can't point to any area of non-warped absolute space and time, can't you point to somewhere that approximates to it, and infer what non-warped space time would be like?

 

I'm sorry to tell you that you have missed the point I was trying to make.

 

So I will try to explain more clearly, working from everday experience.

The full answer to the OP question of what warps space is founded partly in a pure mathematics theorem by Gauss and partly in a principle of physics brought to the fore by Einstein.

 

It also conforms to Studiot's law that fact is stranger than the most fanciful fiction.

So much so that we overlook the implications of everday experience we are so familiar wth.

So to start with that, look at this picture.

 

 

The object is instantly recognisable, despite the unusual orientation.

 

So how do we recognise it?

 

Well we unconsciously use Gauss so called 'remarkable theorem'

 

The version I am using here states that objects look the same regardless of their orientation in a coordinate system, because they have some uniquely identifiable properties that depend only on the object and not on the coordinate system.

Alternatively these properties are the same in all coordinate systems.

(Does that phrase sound a bit familiar?)

 

We can either consider different orientations or the object or the background grid or both as in the next sketch.

Note carefully that I have shifted and rotated the grid in each of the three examples.

 

The petal shape is simpler than the boat but adequate for our purposes because it has varying curvature.

This curvature is called gaussian curvature and it is a fundamental property that is called an intrinsic property because it only depends upon the petal.

 

Because it only depends upon the petal we can in fact take away the coordinate system altogether and just be left with the one dimensional object I call the petal. It is one dimensional because I am only concerned with the thick black outline not the interior and I can calculate the curvature at any point along the petal just by knowing how far along the black line I am. This is called using arc length as a parameter.

 

 

So that is the maths part of the conundrum.

 

The key to the physics part to to realise that the statements about all coordiante systems being equivalent is echoed from the maths into the physics.

But basically Gauss remarkable theorem translates to there is no absolute frame of reference

We can discuss this next time, when you are sure you have got this idea sorted.

Edited May 30, 2017 by studiot

[mistermack]

 

I'm sorry to tell you that you have missed the point I was trying to make.

 

So I will try to explain more clearly,

 

Well, thanks for trying.

[mah123]

I accept that space is not absolute then are we living in multiple space?

for example, I am in earth space, also solar space, also in galaxial space & also in world space.

[Strange]

I accept that space is not absolute then are we living in multiple space?

for example, I am in earth space, also solar space, also in galaxial space & also in world space.

You can define your frame of reference (coordinate system) in each of those, if that is what you mean. For example on Earth or for satellites, we usually use an Earth based system of coordinates. Space probes to other planets use a Sun based system and so on.

 

They are all equivalent so you can choose the most convenient for the job.

[mah123]

I like this, means, Earth base co-ordinate system or sun base co-ordinate system etc...... Means, Big mass create space around it & any other big mass create more bigger space around it.

[Strange]

Masses do not create space. But they can cause curvature of the space-time coordinates.

[mah123]

I have some problems

1) vacuum & space are different or same?

2) space is relative or not.

2) If I put reference frame on earth. I can explain motion of substance near earth only but it can not be used to give answer to motion of substance on other planet or even on moon or galaxial motion. This reference frame can explain only for motion near to earth

or this space is only related to earth only.

3) What is space? it is just mathematical co-ordinate system or something else.

[Strange]

I have some problems

1) vacuum & space are different or same?

 

 

Depends on your definitions of the words. I would say that vacuum (which may not be empty) is what is contained in space.

 

 

 

2) space is relative or not.

 

Measurements of distance etc. (which I would define as "space") are relative.

 

 

 

2) If I put reference frame on earth. I can explain motion of substance near earth only but it can not be used to give answer to motion of substance on other planet or even on moon or galaxial motion. This reference frame can explain only for motion near to earth

or this space is only related to earth only.

 

You can use an Earth-based reference frame to describe anything - motion on Mars or around the Sunor elsewhere in our galaxy. Or even in another galaxy. It just wouldn't be very convenient.

 

 

 

3) What is space? it is just mathematical co-ordinate system or something else.

 

It is just the measured (physical) distance between things. In other words, a coordinate system.

[beecee]

 

3) What is space? it is just mathematical co-ordinate system or something else.

Putting it in layman's terms, space is what stops everything from being together, just as time is what stops everything from happening together, while spacetime is the multi-dimensional framework within which it is possible to locate events and describe the relationships between them in terms of space and time. The concept of spacetime follows from the observation that the speed of light is constant and invariant, Spacetime allows a description of reality that is common for all observers and Intervals of space and time considered separately are not the same for all observers.

Space is real, time is real and spacetime is real:

While spacetime is a non physical entitiy, it is just as real as any magnetic field is real.

[mah123]

but if I fixed reference frame on earth, I can give answer to motion on earth (or near to earth...)

but this earth frame calculation shows that whole world is revolving around it in one day which is wrong. Until I fixed reference frame appropriately, I can not find actual motion of object in that system.

One negative point of reference frame is it is always at rest for it self...