Are these descriptions about extra dimensions really true?

[austinquestioner]

TL;DR Summary

extra dimension accuracy?

I have been trying to imagine extra dimensions for a long time now. I came across this article and it is certainly the most vivid pictures I have ever seen painted of the extra dimensions:

https://phys.org/news/2014-12-universe-dimensions.html

For example, it describes "In the sixth, we would see a plane of possible worlds, where we could compare and position all the possible universes that start with the same initial conditions as this one"

"In the seventh dimension, you have access to the possible worlds that start with different initial conditions."
And so on, until we reach "In the ninth dimension, we can compare all the possible universe histories, starting with all the different possible laws of physics and initial conditions. In the tenth and final dimension, we arrive at the point in which everything possible and imaginable is covered."

This is mind blowing and really cool. Please see the article for a description of all the dimensions. I'm not sure if all this is accurate though or just a misunderstanding or very artistically-licensed description from the mind of the writer??

 

[Halc]

In any of these cases, does it makes sense to talk about what things are like one meter away in the direction of the sixth, seventh, or whatever dimension? Can the possible worlds be lined up in some sort of order with adjacent ones and more distant ones? If not, then expressing it as a dimension doesn't really make sense. You can't do meaningful trigonometry on it for instance.

 

[judiefletcher]

That so-called article is literally gibberish. The number of dimensions in a space is simply the number of coordinates it would require to specify a point. In one dimension, such a number line, you only need one coordinate, x, to define a point. In two dimensions, such as a Cartesian plane, you need two coordinates, (x, y), to define a point. You can add any number of dimensions. It has absolutely nothing to do with anything in that article, which is meaningless silly nonsense.

 

[austinquestioner]

So how do you think he got off writing that? Honest question!

 

[Vanadium 50]

Yeah! I mean, they wouldn't let it on the internet if it wasn't true!

 

[judiefletcher]

Think of a cartesian plane. If you have it on a piece of paper on your desk, then both the x and y axes are horizontal. If you have it on the chalk board, then the x-axis is horizontal, and the y-axis is vertical. So if you had 3 axes, it would not matter which you call x, which you call y, and which you call z. The names are interchangeable. All the spatial dimensions are identical. Usually we write "(m, n)-space" to mean m spatial dimensions and n time dimensions, so we would live in "(3, 1)-space".

The problem with so-called "science journalism" is that journalists are not scientists!

 

[Suekdccia]

So how do you think he got off writing that? Honest question!

Apparently the writer of the article is a journalist and science fiction writer. I highly doubt he studied physics.

This is basically a gross misinterpretation of string theory. Having extra dimensions does only mean that you need more coordinates to specify the position of a point. I know it can be hard to picture these extra dimensions in our heads (since we are used to our 3 dimensional world), but there are some geometrical constructions that can help you to achieve this, at least in part (for example, a tesseract, is basically a cube, which is a 3dimensional figure, "represented" in 4 dimensions: https://en.wikipedia.org/wiki/Tesseract).

Having multiple dimensions does not mean that something bizarre or "metaphysical" occurs. I agree with you that this picture is very cool, but it is only valid in science fiction. From the point of view of physics is just meaningless and nonsense. It's like saying that in 2 dimensions we could find dragons and fairies. Then you go, you draw a triangle in a paper (which would be a 2dimensional figure), and what would happen?: Nothing.

Also you have too keep in mind that string theory and multiple dimensions are purely hypothetical so far. There is no real proof that any of this is correct.

And for your question of "How could the author got off writing that?", the answer is basically: Physics.org and UniverseToday are pages which often try to expose very technical concepts in physics to people uneducated in this field. Although the intentions are usually good, these articles tend to oversimplify, exaggerate or misinterpret these very complicated concepts. You would be very surprised if you saw all the mistakes that these kind of articles usually make (like this one you posted). To have a clearer picture of whatever you are trying to study, try to avoid these pages (or at least read them with a lot of caution) and try to read the papers to which they refer.

Good luck with your studies!

 

[DaveC426913]

I have not read the article, so I may be way off, but...

Multiple dimensions do not have to refer to actual physical spatial dimensions.
Perhaps he is talking about conceptual freedoms of the concept of multiple worlds.

One can construct a many-dimensional array of virtually anything. In this context, a dimension is simply a degree of freedom of a property.

Say, apples: a dimension each for size, colour, mass, roundness, sweetness, etc. That's already a five-dimensional space, and I've barely scratched the peel.

The Myer-Briggs Personality Test is a four-dimensional space (although the freedom in each dimension are merely binary - one of two choices.)

etc.

As a science fiction writer, it's at least conceivable that he lays out such a space as a nursery from which to grow new story ideas:

1. start at Earth, here, now [0,0,0,0,0,0,0,0]
2. move across the 'alternate worlds' dimension to, say [0,0,0,+5,0,0,0,0] (the Chixulub Asteroid never wiped out the dinosaurs)
3. move back in the 'history' dimension to [0,0,0,5,0,0,-2000,0] (Roman Times).

Now you've got a historical alternate world where sapient dinosaurs formed The Eagle of the Ninth.Caveat: I'm not suggesting this is what the author is actually trying to do, merely suggesting to the OP that there are many kinds of useful dimensions other than just manifest spatial dimensions. Food for thought, as it were.

 

[judiefletcher]

Nowhere in the article does the writer say that they are discussing science fiction or making suggestion for science fiction writers. It sounds to me that they believed that they were talking about physics. From the point of view of physics, what they were saying is nonsense. If you are talking about science fiction, this thread should be in a forum about fantasy and science fiction.

 

[hmmm27]

Superstring Theory

 

[empdee4]

Despite popularity and verification of certain particle models, one critical question is where the UN-observed micro dimensions are. In this regard, it is meaningful to point out that symmetry doesn’t need to be from rotations among linear axes, but can be among 2d planes.
While this is not immediately obvious, it is logical and not hard to understand. Many contemporary theories are modelling electromagnetism, which is the most beautiful theory in physics. But EM is beautiful only because the 4d spacetime in which it is expressed is defined by EM itself. However, the role EM plays in the definition of 4d spacetime in special relativity tells only half of the story (i.e. light speed must be measured at constant, c). No less important is the other half, i.e. the 3 circular magnetic and 3 electro field lines on the 6 planes of the 4d spacetime, which define the “equivalencies” between the 4 linear axes. This is critical because without it light would not be measured at the same speed in different directions and rotational symmetry of photon is lost.
By the same token, the 6 plane angles of the 4d spacetime cannot be equivalent unless they are defined by “real physical” fields rotating among the 6 planes. (Without these equivalencies, a full circle on xy-plane may be 360 degrees, while that on yz-plane 362 degrees, etc. and the spacetime is warped and the 4 axes cannot be perpendicular to each other.) This is conjectured to be weak interaction field. An SO(6)~SU(4) symmetry surfaces when these equivalencies are secured by the weak fields. But this symmetry is not between linear axes but between “2d planes”.
Spacetime being flat evidences the existence of these “weak” fields running among the 6 planes.
While this offers internal symmetry without the need of the “unobserved” micro dimensions, it also provides a gauge theory as beautiful as EM.

 

[empdee4]

Would this be a sensible theory?

 

[dx]

It should be mentioned that extra dimensions in string theory are not simply increasing the number of coordinates above the usual four coordinates. The extra dimensions have some peculiar properties. The size of the extra dimensions is described by a field called the dilaton, and this object also controls the coupling constant g of the strings. And a compact circular extra dimension of radius R is equivalent to a compact dimension of radius 1/R. Also, 10 dimensional string theories can be thought of as having a very small 11th dimension which is not normally visible, which grows into an 11th dimension in certain limits.

 

[elcaro]

Yeah! I mean, they wouldn't let it on the internet if it wasn't true!

Where are the facebook factcheckers when you need them?

 

[DaveC426913]

Also, 10 dimensional string theories can be thought of as having a very small 11th dimension which is not normally visible...

As opposed to the ostensibly huge 5th through 10th dimensions?

 

[arivero]

No physics here, only literature. It is just a variation of a old folklorical piece, a counting song

https://en.wikipedia.org/wiki/Green_Grow_the_Rushes,_O is a well known example. Also "Las doce palabras retorneadas", in Spanish. Kölher and other researchers suggest that the oldest prototype is a Zoroastrian history, a chapter of the Arda Viraf.

 

[DaveC426913]

Nice.

_{(Somebody had to say it.)}

 

[ohwilleke]

No physics here, only literature. It is just a variation of a old folklorical piece, a counting song

https://en.wikipedia.org/wiki/Green_Grow_the_Rushes,_O is a well known example. Also "Las doce palabras retorneadas", in Spanish. Kölher and other researchers suggest that the oldest prototype is a Zoroastrian history, a chapter of the Arda Viraf.

View attachment 289406

There used to be eight good celebrities? I guess some of them died.