The Unbended Curved Bar Space Slugout Thread

Hi BuzSCENARIO
Imagine your steel bar with a small laser attached to the top of it (kind of like a laser sight on top of a rifle). The laser beam is aimed along your perfectly straight steel bar so that the beam of light and the steel bar are perfectly parallel.CONVENTIONAL SCIENCE
Now we know that light "bends" due to spacetime curvature because we have observed it. We can demonstrate, measure, predict, repeat etc. etc. etc. this effect. It is "proven" (to the point anything is proven in science).
Now in actual fact light does not "bend" in curved spacetime. Rather it travels in a straight line but appears to bend because spacetime itself is curved. This is the view of conventional science. Thus the steel bar and the light beam would both be straight. Would never deviate from their parallel paths. And would both eventually meet at the ends in a 4D spherical spacetime universe. According to conventional science.BUZSAW MODEL
In the case of your perfectly straight steel bar and my additional associated laser beam of light - At what point, according to your definition of straight, do the perfectly straight steel bar and the perfectly straight laser beam of light deviate from each other such that one is straight and the other is not? What does your model predict should happen in the steel bar laser combo situation?Edited by Straggler, : No reason given.Edited by Straggler, : No reason given.

Have you seen Message 13?What would your model of the universe expect if a laser beam were to be shone perfectly parallel to the steel bar in question?Would the light beam and the bar deviate from their parallel paths at all?

Buz you seem very reluctant to consider the question posed in Message 13Is this because you are not confident enough in your Kindergarten cosmology model to actually hold it up to scrutiny?

Well if we followed your definition of space the GPS system would be a big mess because we would not be able to calculate or allow for the effects of curvature. That minor but practical consequence alone suggests that your hypothesis is wrong. The properties that allow for it's curvature? What does that even mean? What could be a possible answer? It's colour? It's plasticity? The wieght of space? It's geometry? It's favorite flavour of cheesecake? What do you mean? Can you give an example of the sort of answer you are looking for?Curvature is a property of space. Your question is like asking what property of a circle allows it to be circular. Curved spacetime works in every practical, calculable, predictable and observational scientific sense. Your kindergarten cosmology model does not. So obvioulsy you must be right...............?

Buz
The reason a 2D model is often used is because it aids the conceptual model of spacetime as 4 dimensional (where time is the 4th dimension). We obviously cannot think in terms of 4 dimensions because we are limited to 3 spatial dimensions. Try creating a physical 4D model if you do not believe me!!How are we to try and conceptualise the idea that the spatial dimensions we experience are geometrically equivelent to the surface of a 4D sphere?
We do this by imagining the perspective of something dwelling in the 2D surface of a 3D sphere. The sort of spehere we can conceptualise physically. Hence the 2D anlogy used with regard to "straightness" etc.That is why we talk about 2D analogies and models. Those who understand the maths of these things do not necessarily need such models but it is the best method of explaining these things to those who may not have the mathematical knowledge to conceptualise from equations alone.The aim is not to trick. Not to obfuscate. Not to deny reality. And not to deny God. The aim is to simplify the conceptual point such that it can be understood without maths. It is a simplistic model to aid understanding.

Spacetime is 4 dimensional. Surely you agree with that?

Geometrically we must therefore work with a 4D model. Surely you agree with that?

Using a 3D model for conceptual simplification is a valid method of visualising things like "straightness" in a spherical model. Surely you agree with that?

Imagining things from the perspective of a being living in 2 spatial dimensions with time as the third dimension is a valid way of exploring the idea of dwelling in a 3D surface of a 4D sphere. Do you understand this?

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Whether you agree with the model or not is irrelevant. An appreciation of why such 2D models are valid and used is achievable.
It really is not to pull the wool over people's eyes. Quite the opposite in fact.

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Do you understand this now? Or do you still think we are all just trying to con you somehow?

A perfectly straight 3D bar is perfectly straight in 3D space. However it is "curved" in 4D spacetime. Can you suggest an experiment that could be done to falsify these conclusions and verify your own kindergarten cosmology model?Edited by Straggler, : No reason given.

So how do you determine that your bar is "absolutely straight"? What defines "straight" in your model?Without defining this the rest of your argument is completely, utterly and totally meaningless

Yes. Good point succinctly made.Buz has basically got to demonstrate that space is not capable of curvature at all if his argument is to make any sense at all.But then his argument doesn't make any sense at all....... oh well.

"Hypothetically straight"? What on Earth does that mean? That is not a "model". It's meaningless. If the bar is straight in 3D space then it will be curved in 4D curved spacetime. Actually the reason we have two eyes is to add depth of vision. We are "designed" () to see a 3D world and do indeeed see in 3D. Have you not seen Jaws 3? No Buz. No extra spatial dimensions are added in GR. 3 spatial dimensions and time. Time is the 4th dimension. It has nothing to do with teaching GR. 4 dimensions are used because time exists. No Buz. No extra spatial dimensions are added in GR. 3 spatial dimensions and time. Time is the 4th dimension. Your ongoing insistence that GR is inventing unevidenced dimensions is just plain wrong.Do you deny time exists?
How many dimensions, including time, do you think there are?3 spatial dimensions + time = 4 dimensions.
Thus spacetime geometry is 4D You never even made it to square one Buz. You still think we see the physical world in 2D. You still think a 3D straight bar can be defined as straight without reference to anything but a meaningless concept of "hypothetical straightness". You still fail to even understand why 3 spatial dimensions + time might require 4D models. It is utterly evidenced by means of specific measurable prediction. Practical applications of these measuremenst are used every day, all over the world by GPS users.
The only people who doubt the veracity of this are those, such as yourself, with philosophical reasons of their own making to insist it is untrue regardless of evidence. Your 3D bar is stratight in 3D. Nobody is disputing that.
However in 4D curved spacetime it is necessarily curved. In a 4D spherical universe - Yes they would. OK. But in 4D spacetime it would still curve. The crux of this issue comes down to spacetime curvature.
A "hypothetically straight" bar in curved spacetime would have to pop out of space somehow. Even you are not suggesting that.Question: On what basis do you declare that 4D spacetime (i.e. 3 spatial dimensions + time) does not curve given all of the mass of evidence that says that it does?Edited by Straggler, : No reason given.

There appears to be no hope for you regarding some of these issues but I am determined to get you to understand something as part of this discussion.
I want to demonstrate to you why 4D models are used. You don't have to agree with their use. You don't have to accept GR, space-time curvature, "bent" straight bars or anything else.Just please for the love of God try and listen.
I just want to try and show you why a 4D model is legitimately used.Ready..........? Let’s take one step at a time in familiar language. Drawing the graphs on a piece of paper might helpONE SPATIAL DIMENSION + TIME
Consider one of the spatial dimensions in question. "Height" for example.
If we want to draw a graph showing how the height of a ball (or whatever) changes in time we can draw height as one axis (the vertical axis) and time as the other (the horizontal axis). We can plot the height of the ball against time using this model. Thus we can model the path of a ball in terms of it's height as time progresses. A ball thrown straight up in the air and landing again would look much like a hill shaped curve on our graph. The top of the "hill" would be the point that the ball reached its maximum height.Do you agree with this simple model?TWO SPATIAL DIMENSIONS + TIME
Now let’s consider a ball thrown between two people. Imagine each of the two people stands at either end of a 20 foot straight metal bar laid on the ground of a park. Normal Earth gravity still applies. How can we graphically plot the path of the ball now? Well we still need to be able to plot the height of the ball. We still need to be able to plot the progression of time. But now we also need to be able to plot the position of the ball along the length of the bar as well. We need an extra axis on our graph.Take your graph from the one spatial dimension example above. Where can we add an extra axis to plot length? This axis would have to come out of the page. The three axes would therefore form the corner of a cube.Thus with a co-ordinate for height, a co-ordinate for length and a co-ordinate for time we could plot the position of the ball at any point. Three co-ordinates. Three axes.Do you agree with this simple model?THREE SPATIAL DIMENSIONS + TIME
OK. Now lets make a 20 foot by 20 foot metal square plate and lay this on the ground of our park. We now have a person standing at each corner of the metal plate. They can all throw the ball to each other.How can we graphically represent this on a graph? Well we still need to be able to plot the height of the ball. We still need to be able to plot the progression of time. We still need to be able to plot the position of the ball in terms of length. However we now need an extra axis on our graph to represent breadth.To fully plot the position of the ball we now need a co-ordinate for height, a co-ordinate for length, a co-ordinate for breadth and a co-ordinate for time. With these 4 co-ordinates we can describe the motion of the ball at any point in 3 spatial dimensions and time. Four co-ordinates. Four axes.Do you agree?THE POINT
Now Buz surely you can see the problem here. The two spatial dimensions + time scenario required a 3D graph shaped like the corner of a cube in order to fully represent the motion of the ball.In the case of the three spatial dimensions + time scenario we effectively need a set of axes that form the corner of a 4D cube.
Try adding this onto your graph formed in the previous examples!!!!4 co-ordinates. 4 axes. 4D graphical representation.QUESTION: Can you now see why modelling 3 spatial dimensions + time requires a 4D model?

AAAAArrrrrRRRRRgggggHHHHH!!!!!!!!!!!Nobody is denying 3D space. GR does not deny 3D space. GR inherently assumes 3 spatial dimensions.
Nobody is creating extra spatial dimensions. GR is not based on the need for extra spatial dimensions.Your whole argument is based on a complete misapprehension of everything that everybody is saying to youThe whole reason the maths of GR is done in 4D is because there are 3 spatial dimensions. Plus time.
One axis for each spatial dimension. Plus one axis for time. Hence 4D geometry. Not to obfuscate. Not to confuse.4D GEOMETRY BECAUSE 3 SPATIAL DIMENSIONS PLUS TIME REQUIRES A 4 DIMENSIONAL GRAPHICAL REPRESENTATIONI have explained this to you in Message 127. You have ignored this. If you don't understand it ask and I will explain.It seems that in this thread your only aim is to insist that you are right regardless of what is said. To this end you seem intent on ignoring anything that might cause you to question your assertions. Even those outrageaous assertions that you are repeatedly making regarding the motivation of scientists in choosing the mathematical model used.Frankly Buz this is willful ignorance at best and verging on the dishonest at worst...............Edited by Straggler, : No reason given.Edited by Straggler, : No reason given.

No No No No No No. And for the last time - NO.Forget GR. Forget "straight" curved bars. Forget curvature. Forget photons, light beams, infinity, the universe and all of the rest of it. Forget all the physics you find contentious and ungodly. None of it need even be considered for you to get this extremely simple point.Just consider a group of guys throwing a ball around a normal everyday park. It really is that simple.You cannot fully graphically and mathematically represent the everyday situation of a ball being thrown around a park without considering 4D geometry.See Message 127 which attempts to explain this at a level you should be able to understand. If not then feel free to ask questions. No. This has nothing to do with parallel dimensions.
Four guys. One ball. In a park. No parallel dimensions required.Please read Message 127 and then tell me how you would go about modelling a ball being thrown around a normal everyday Earthbound three dimensional park as time progresses without needing to consider 4 dimensional maths.Please just try and accept the fact I am trying to help you understand the need for 4D maths. The whole "straight" bar thing is a lost cause with you as far as I am concerned but an understanding of why 4D maths is considered to be needed is, I believe, within your grasp if you will just stop being so damn stubborn and actually listen.Four guys. One ball. In a park. Demonstrates all you need to know to get this point
See Message 127 and I hope to hear back from you.Edited by Straggler, : No reason given.

Yes you are almost certainly right.But I live in eternal optimisim that the multidimensional depths of Buz's ignorance are surmountable Straight bars etc. etc. I give up. But........
If he is willing to accept anything other than his preconceived notion that we are all trying to fool him with some fancy jiggery pokery mathematical mumbo jumbo then I think he might well be able to grasp why we keep on about this 4D thing.If..........

My only aim is to try and make you understand why it is that 4D maths is necessary and not some sort of big con as you relentlessly keep asserting. This involves nothing more than the ability to count.If you want to plot the motion of a ball in 3D space (e.g. in a park) on a graph you need 3 axes and 3 co-ordinates to describe the position of the ball at any point. Your axes will look like the corner of a cube.If you want to add another axes to your graph to represent time so that you can show the motion of the ball in 3 spatial dimensions plus timeThen you need four lines all at right angles with each other. This is a 4D graph. Hence the 4D maths.3 + 1 = 4. It is that simple.I again suggest you read Message 127 for a more detailed explanation of this depressingly simple concept.Edited by Straggler, : No reason given.

Yes that is quite mind bending. Cheers for the correction and clarification.At this point all I even hope to get Buz to understand is that when we talk about 4D we are not, as he repeatedly asserts, inventing unevidenced parallel dimensions for the purposes of conning old men into believing the ungodly idea that straight bars do perverse and unrighteaous things like meet up at the ends. Rather we are merely talking about giving a co-ordinate for each of the 3 standard spatial dimensions plus time and that to do this requires 4 axes and therefore 4 dimensional maths.Wish me luck.........Edited by Straggler, : No reason given.