Basic Error: The accelerating Universe conclusion - reason

[Gibsense]

The science:
By measuring about 2,400 Cepheid stars in 19 galaxies and comparing the observed brightness of both star types, they accurately measured their true brightness and calculated distances to roughly 300 Type Ia supernovae in far-flung galaxies.

The team compared those distances with the expansion of space as measured by the stretching of light from receding galaxies. They used these two values to calculate how fast the universe expands with time, or the Hubble constant.

The error: An assumption that the stretching of light from receding galaxies was due mostly to the expansion of space.
The alternative: The redshift (light stretching) observed was largely due to time dilation.
The logic: The spherical nature of the universe at extreme distances approaching t=0 introduces extreme curvature. The curvature acts to observe in much the same way as the spatial curvature on approaching a black hole. In both cases, space and time are rotated and time dilation occurs (at t=0 the rotation is 90 degrees).
NB I think the major misunderstandings are about:
1. That time has a specific dimension; this is not correct. There are 4 spatial dimensions. Time can 'act' in any direction of the 4 allowing the other 3 to be 3D space. However, do remember the radius is proper 'cosmic' time history and the radii of a sphere point in all possible directions of 4D space - I am referencing a hypersphere (a type of sphere)
2. That our position (on the sphere) is not unique. It is relative. If you moved a few billion light-years around the sphere t=0 would have shifted correspondingly (at 90 degrees to your time and space). It, t=0, results from curvature - not an approach to the BB. (similar to space curvature at a black hole)
3. The assertion that hyperspherical space curvature produces time dilation is only special relativity applied on a large scale (ignoring the effect of mass and relying on a homogenous nature of the universe).
4. Time is not a dimension but a process acting on the universe in any of 4 spatial dimensions but - within a hypersphere - in a radial direction primarily (cosmic/proper time) and rotated from the radial by speed. IMO
5. Time (locally) always acts at 90 degrees to the local space including where space is shaped by mass

 

[Helio]

The alternative: The redshift (light stretching) observed was largely due to time dilation.

Yes. This was, IIRC, an element within de Sitter's modeling in 1917. The view was that the wavelengths would become longer due to time dilation of the atom emitting the photon, thus making it more red than what his observed on Earth.

Others, such as Lanczos, Weyl, Lemaitre, Roberson, and Tolman, also worked within the framework of de Sitter's model. The main competitor was Einstein's own cosmological model.

Einstein knew his model was only favorable in math terms, not in physics terms. His model, as he knew, had no explanation for the redshifts observed by Slipher (1912 and later).

De Sitter's model did offer an explanation for redshift observations, but his model had no matter in the universe. That's a problem.

When Edington showed de Sitter the model from Lemaitre (spacetime expansion of a dynamic universe, not a static one), he immediately recognized its brilliance. By 1931, Einstein quickly corrected his harsh criticism of Lemaitre's model and accepted it.

If you study de Sitter's model, you might find something to help your vision of cosmology.

 

[Gibsense]

If you study de Sitter's model, you might find something to help your vision of cosmology.

Will do, thanks

 

[Gibsense]

[/url][/IMG] I looked at the diagrams for Lemaitre's ideas and modified the labels. All similar diagrams have time as some mysterious arrow which I have changed to Imaginary time. Also, the space within the circles normally represents nothing, but in the chart, it is the expansion driven by our 'ordinary' time. Each ellipse represents a hypersphere (that is 3 dimensions dropped to leave just a circle - the circumference is the hypersphere)
NB no acceleration of expansion is shown (I think it could be misleadingly due to time dilation)

A stretch too far maybe but consistent with my other posts regarding a Quantum Landscape the surface of the expanding cylinder might be considered as the 'Quantum Landscape' modified as the universe passes in Imaginary Time.

 

[Atlan0001]

SPACETIME is entirely relative, Gib. So, therefore, all past-future tense is relative.

 

[Gibsense]

es. This was, IIRC, an element within de Sitter's modeling in 1917. The view was that the wavelengths would become longer due to time dilation of the atom emitting the photon, thus making it more red than what his observed on Earth.

Yes, I am aware time dilation is involved via other means than my suggested one. I am adding a time dilation resulting from shape alone. The same principle as time dilation at a black hole but on a universe scale from the shape of a sphere.

 

[Gibsense]

SPACETIME is entirely relative, Gib. So, therefore, all past-future tense is relativ

Ok but bear in mind that spacetime is inside the ellipse (s)

 

[Catastrophe]

Gibsense, re yr diag in #4. I know your posts are much more sophisticated than my flatlander analogy, but I am looking to see if there is some mutual interaction.

Thank you for:

Page 4 - Flatlander 3D: Hypersphere to Flat Space

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Looking at yr diag., you suggest subsequent hyperspheres at imaginary times.
In my version, I include time within the universe, so that subsequent spheres indicate expansion of the flatlander universe. Nevertheless, expansion suggests passage of time. In my analogy, this is apparent to the D+ being. I suppose also to the flatlander, but assumed as direction of change through expansion. So, I like "imaginary time" as labelled.

As you know, the object of my analogy is simply to try to understand "expansion into what?", which is a problem for the flatlander (and for me, in our world), but not for D+.
Hence, I deduce (just as a prop) that the answer would be apparent, if we could access one dimension higher up.

I would find it very interesting if you could summarise your objective as briefly.
Not suggesting that brief is better, but it help my understanding to start from "one step higher up".

Cat

 

[Catastrophe]

Gibsense, I am aware of this:

There are previous posts regarding the Flatlander illustration: How a 2D flat person would perceive a 3d object passing through a 2D flatlander plain. This post applies the same principle to the interpretation of 3D Flatlanders viewing a 4D universe. The Hypersphere and its 3D space (the surface) are described in a previous post.

. . . . . . . . . but was this the real primary objective?

Cat

 

[Gibsense]

I would find it very interesting if you could summarise your objective as briefly.

Hi Cat, I have difficulty knowing where we differ as I am happy with your analogy.
But guessing: have another look at the 3D/4D diagram. My objective was to show how we as 3D flatlanders would interpret events occurring at equal intervals along a hypersurface (the sphere surface/ the circle).
As flatlanders, we would only perceive the tangent from the circle; instead of equally spaced intervals, we would see intervals crowded together at a far distance near what we would think was the BB. The 4D 'superbeing' would know it was a quadrant of the universe not a BB.

I have 'projected' the events on the hypersphere to a flat tangent space that a 3D flatlander would think was reality.

 

[Gibsense]

Gibsense, I am aware of this:



. . . . . . . . . but was this the real primary objective?

Cat

Sort of. I was hinting at Astronomers preferring an easy simplicity of flat Euclidian space and trying not to be divisive and rude. Whatever, it seems to me that even in an open universe scenario giving a trumpet shape there is curvature and the only infinity is that where expansion continues forever. The idea that 3D space is infinite does not sit well with me except infinitely circular but bounded.
This looks unclear, sorry. maybe a second attempt if you wish.

 

[Gibsense]

As you know, the object of my analogy is simply to try to understand "expansion into what?", which is a problem for the flatlander (and for me, in our world), but not for D+.
Hence, I deduce (just as a prop) that the answer would be apparent, if we could access one dimension higher up.

Agreed

 

[Gibsense]

Cat and the Balloon analogy

Balloon = Sphere (n-sphere, whatever)

Cat says to blow up the balloon and the dots on it separate by the intervening space increasing = a spherical expanding universe with galaxies separating as the space between increases.

But on the 2d surface of the balloon/sphere, Cat has galaxies confined to the surface therefore the surface must be 3D space = Hypersphere!

Cat's description is not just an analogy (although intended as such perhaps) but is an accurate description of a hypersphere. This is why I thought we were in total agreement.

Does this help or make matters worse?

 

[Gibsense]

As you know, the object of my analogy is simply to try to understand "expansion into what?", which is a problem for the flatlander (and for me, in our world), but not for D+.

Ah, I have never taken this literally as an issue as there is a what or there isn't but not to let it be an issue however.....
Let's say you have a dog in a kennel. It is fed but never let out. It's the universe is the Kennel. But the Kennel is in a yard and it is let out in the yard one day. It's the universe is the yard.
But the yard is in an estate that it knows nothing about - and so on but the world is a sphere and the infinite progression is bounded after all.

So, astronomers and mathematicians cover all possibilities by using the term "Embedding Space" to hedge their bets. I have a feeling I describe sucking eggs for which I apologise. But to say one step at a time

 

[Gibsense]

Many years ago (like so very many) an Astronomer said to me:

"John, beyond this universe is nothing". I said 'ok so space with nothing in it'

He said "No that's not right there is no space as space is not nothing it is space"

So I said, "What is nothing?" and he said, " You cannot even ask the question"

Nowadays that has all changed and the dog's exploring the yard

 

[Catastrophe]

Gibsense, that does help, although I get the impression that you seem to, perhaps, attach more "reality" to the "analogy" than I do. I set out with a very simple aim - to form an idea, however simplistic, - a peg on which to "hold on to" "expanding into what?".

The last thing I wanted was "back to square one", giving D+ as the personification of BB!
Whilst some might interpret it that way, I look on it more like a human trying to understand how how a limited "surface living creature" on our planet might understand things.

In fact, I now find myself approaching what you are saying "from the other end" without realising it. But now, perhaps, my aim seems different to yours. Hence I ask "Were you just trying to understand expand into what? But it seems that you were explaining the observer, rather than the event. Two different approaches to the same thing? Or not?

Cat

 

[Gibsense]

In fact, I now find myself approaching what you are saying "from the other end" without realising it. But now, perhaps, my aim seems different to yours. Hence I ask "Were you just trying to understand expand into what? But it seems that you were explaining the observer, rather than the event. Two different approaches to the same thing? Or not?

You may be right but I am not sure I understand. I know you like a Mobius strip - it is satisfying in that it is complete in a way. If you were considering a dog discovering a yard etc I was just saying we have to keep looking outward and one day maybe we will get the whole picture, maybe. I get the feeling I am missing your point!

 

[Catastrophe]

Gibsense, your dog is my flatlander, but I cannot let the flatlander out. It takes the dog's master to understand the dog's predicament, but he (D+) cannot release the dog - only understand it.

Cat

 

[Gibsense]

Referring to the diagram on this thread I remember reading The Universe in a Nutshell by S Hawking. He said the concept of Imaginary Time was used in Quantum Mechanics and was conceived as a time dimension at 90 degrees to 'Real Time'. The diagram incorporates both and is consistent with other posts I have made.
It was in response to a suggestion that I explore some other concepts already made

 

[Catastrophe]

and . . . . . . . . .

As the radius of the sphere increases linearly, the area increases as r^2.

So D+ sees linear expansion from a (non existent) centre, but flatlander experiences expansion proportional to r^1.

Cat

 

[Gibsense]

Gibsense, your dog is my flatlander, but I cannot let the flatlander out. It takes the dog's master to understand the dog's predicament, but he (D+) cannot release the dog - only understand it.

Yes, True.

 

[Catastrophe]

Basic Error: The accelerating Universe conclusion - reason​

So I was not off track, after all. According to the analogy, of course.

Cat

 

[Catastrophe]

Gibsense,

The error: An assumption that the stretching of light from receding galaxies was due mostly to the expansion of space.

Has this anything to do with r^2

D+ sees linear expansion of r, but flatlander sees expansion per r^2.

The map was not the territory.
One word - expansion - meant different things to different observers.

Cat

 

[Gibsense]

As the radius of the sphere increases linearly, the area increases as r^2.

Yes, but I was comparing it (the radius) with the Hubble Constant which is a distance not an area as a means to show that the ideas are, in a way a circular argument. At any given time in the universe's age (radius), the increase in the radius determines the increase in the circumference and therefore the Hubble Constant. If you know the age you know the expansion. If you know the expansion you know the age. Just simple geometry. It matches observational reality.
That is about my limit in concept. A slice halfway through a hypersphere is a sphere. From there I use the circumference. Atlan0001 pointed out that you can slice a hypersphere any which way and have an endless number of spheres of all sizes. I restrict consideration to a sphere of the same circumference dropping a dimension to do so.

 

[Catastrophe]

Yes, but I was comparing it (the radius) with the Hubble Constant which is a distance not an area as a means to show that the ideas are, in a way a circular argument.

That is because you are D+ in my analogy, but the flatlander experiences r^2.

Cat