Does a cosmic 'glitch' in gravity challenge Albert Einstein's greatest theory?

[billslugg]

I know that lots of people claim there are many more spatial dimensions but I don't buy anything I don't understand. String Theory is right up there with cryptocurrency.

 

[Questioner]

The 'standard' rubber sheet model is analogous to stretching 2D space-time into a 3rd, higher dimension. By measurement that makes mass fields longer (encompassing more space) than an orthogonal projection of the otherwise 2D sheet.

That's what it does. I don't know how one reconciles that with treating higher [than 3D space] dimensions as fantasy.

I think that illustration/modelling is completely contradictory to what mass/gravity actually does/is.

 

[billslugg]

The rubber sheet is simply a 2D representation of a 3D distribution. It is not intended to look like the actual thing any more than your electric usage graph on your power bill looks like electricity.

 

[Questioner]

That's the geometry of it,
so how else does one understand it?

 

[billslugg]

One could model a complex gravitational field as a bunch of clouds of increasing density wherever the field is stronger. Geodesics would follow lines of constant density. It would not be very intuitive. It would only work well if you had 3D glasses and could walk around inside it, as some areas would block your visibility. This is the advantage of the sheet model, it lends itself well to a flat piece of paper.

 

[Questioner]

A highlight of relativity is that what is understood as a force becomes conceptualized as geometry.

And you're saying this geometric model doesn't actually represent geometry?

Really?

It seems like a cutesy thingamabob that doesn't contribute to rational understanding.

It's grossly misleading hand waving as far as i can see.

 

[Gibsense]

There are only 3 spatial dimensions. One temporal. When scientists say they need many more dimensions to describe something they are talking about things like temperature, pressure, smell, whatever. Note: It is more complicated than that but that's your basic idea.
Additional dimensions of space would be outside of our physics. Aka "magic". I don't buy into it.

I suggest at least 4 spatial dimensions, but it depends on the context.

Our universe has three spatial dimensions and time. Time is possible because our universe is 'embedded' within a 4-dimensional space.
This is proven (?) by the interchangeable use of light years and years.

Time, I suggest, is our universe travelling in that 4th spatial dimension.
Whatever, n+1 spheres (any number of spatial dimensions) are used to solve many issues according to Bing AI which suggests a reality.

 

[magnoflux]

To balance the universe electrically will require the stars and our sun to be made of anti-matter.
If we fire a rocket with tons of space junk directly at the sun the anti-matter positron atmosphere there will annihilate and electron enclosed matter and no MC^2 explosion will be seen.
The positive and negative charges will all cancel out kg for kg but possibly a small flash as the spin inertia escapes .
Worth a try.

 

[Questioner]

(Obsessively riding the issue...)

If mass curved into a higher dimension not only would a planet/object block its 'empiric' light cone it would block an even wider light cone because it would deflect/curve away the light passing through its significant mass field.

Instead mass fields 'lens' light so we can 'around' its edges reducing its light cone shadow.

A really good place to do a simple length measurement of distance through a mass field is around the Moon, because it has no complicating atmosphere to speak of.
One could launch a cesium clock on vector that would skim near the Moon's surface and it would probably be sensitive enough to differentiate between a straight or curved shortened path.

Honestly a generic shortened path is pretty much a given because time passes slower in a mass field, but distinguishing between a curved (slightly elongated) or confoundingly straight (slightly shorter than 'expected') line would be demonstrably insightful on the exact geometry.

It would show the difference between whether mass curves space or actually straightens/shortens it.

 

[Questioner]

One can also use the centripetal force/effect as well, to detect curvature. Does the Earth in its orbit of the Sun exhibit any centripetal force/effect?
Does gravity seem increased at equitorial noon and decreased at equatorial midnight or not.
If not that would mean our orbit was actually traveling a straight vector.

 

[Helio]

One could model a complex gravitational field as a bunch of clouds of increasing density wherever the field is stronger. Geodesics would follow lines of constant density. It would not be very intuitive. It would only work well if you had 3D glasses and could walk around inside it, as some areas would block your visibility. This is the advantage of the sheet model, it lends itself well to a flat piece of paper.

Nicely stated, though I'm no expert on GR.

Every analogy requires some imagination. The rubber sheet model just happens to require more of a .... stretch.

I've been reading some of the basics to the early solutions to GR. It was Lemaitre who may have been the first to separate space (3D) and Time (1D). He did so, apparently, to produce homogeneity, which he discovered was lacking in de Sitter's model.

 

[Questioner]

Mass creates a continuous transition geometry from (neutral 'base') 3 dimensions to less than fully 3 dimensional space around matter.

Matter's mass is the shrinking, tightening, straightening of space.

The Earth travels in a straight line,

around the Sun.

Venacularly 'curve' means a linear (unambiguous sequence of points) element that requires an additional dimension to 'smoothly', continuously extend into/through.
While technically a line is categorically a 'curve' most people would say a straight line is not a curve.

To say mass 'curves' space is incredibly misinformative.

Matter shrinks immediate peripheral space, PERIOD.

Why make it sound like it's some mystical mysterious wandering 'curve' when cognitively it is exactly the opposite?

Is that physics confusion or is that trying to keep the 'shrooms' in the dark by feeding them compost?

 

[Questioner]

Using geometry to illustrate mass geometry that doesn't reflect & operates in direct contradiction to the actual geometry.

Wow! What a genius way to 'inform' people.

I guess that's what education can do for you or to you. lol

 

[Questioner]

Use up to illustrate down & down to illustrate up.

Now I get it.

 

[Questioner]

Like using a sharpening angle to illustrate, 'correlate' with a circular progression.

 

[George²]

In a Cartesian coordinate system if one telescopes the demarcations together that would shrink the spatial reference frame.

This is not an actual contraction of space, but a defect in humanity's mathematical abilities that results in incorrect geometric renderings. I don't know if we would be able to fix this defect.

 

[Questioner]

An analogy is one is traveling a mile per minute and passes one mile marker each minute.
Then one finds one's self passing a marker every thirty seconds.
The question is has one doubled one's speed or have they added indistinguishable half mile markers as well?

With space contraction the question is would the objects in space contract as well.

Matter is never out of its own mass field,
but can go in & out of some other matter's mass field.

 

[Questioner]

By velocity measurement a mass space proximate to a matter body is shorter.

I'm pretty sure if one had a long enough tape measure it would concur measuring that distance through a mass field.

So did the tape measure stretch to measure the distance or is there in fact less space/volume in a mass field?

 

[Gibsense]

One can also use the centripetal force/effect as well, to detect curvature. Does the Earth in its orbit of the Sun exhibit any centripetal force/effect?
Does gravity seem increased at equitorial noon and decreased at equatorial midnight or not.
If not that would mean our orbit was actually traveling a straight vector.

Yes, a straight vector indeed! But not fast enough to escape gravity. Therefore it falls (continually falling) compensated by the straight vector resulting in an orbit. There is then only the imaginary centripetal force caused by the straight vector (as if trying always to escape. I must apologise if I misunderstand your comment

 

[jomamareid]

"Slower time makes moving things (to themselves) seem to travel faster, which is equivalent to shrinking space." - Questioner

It's the other way around, mass slows time only for someone observing from afar. To the person near the mass, time moves at normal speed.

I've always wondered if The gravity of a mass can have a rebound effect on massive objects that cause a rounded bend in space, like a trampoline, as the mass shrinks will the bend in space snap back, speeding and slowing objects in its wake as it springs.

 

[Questioner]

Here's a really tough one to get one's head around,
Kepler measured the changing speed ellipses of most planetary orbits and yet inertia is following a straight line constant velocity.
No magical forces.
I'm pretty sure the tighter foci are at different distances from the Sun.
Maybe it relates to the fact(?) it takes time to reconcile the inequitable distribution of space [& time?]?
It takes time for space to 'sink' (synch?) in?

 

[Questioner]

I've always wondered if The gravity of a mass can have a rebound effect on massive objects that cause a rounded bend in space, like a trampoline, as the mass shrinks will the bend in space snap back, speeding and slowing objects in its wake as it springs.

Interesting idea.
There is frame dragging around rotating bodies.
It seems like some kind of space 'friction' or at least interaction with mass. (Something to do with the centripetal effect?)

Gravity waves are tiny implying that space is really brittle/tight.

Basically space would be storing and then releasing energy.

 

[George²]

I've always wondered if The gravity of a mass can have a rebound effect on massive objects that cause a rounded bend in space, like a trampoline, as the mass shrinks will the bend in space snap back, speeding and slowing objects in its wake as it springs.

Not needs to wondering. Just read.

 

[Atlan0001]

The Moon long ago orbited closer to the Earth than it does now. It has moved farther out in its orbit, not closer in. Its orbital track is expanding out.

Long ago, Earth's spin, it's day night cycle, was 14 hours rather than the 24 hours it is now And that SPACETIME is expanding, stretching out bit by bit as regularly measured now.

The Q-Verse stop watch kind of constant timing of all of the above, very apparently, hasn't slowed down, hasn't stretched out, one bit!