# Higher dimensions and symmetry

1. Apr 15, 2007

### flashgordon2!

I can't quite remember where I got this idea, but once my brain remembered one point about higher dimensions(that of how each higher dimension, at least in terms of the first three dimensions, is at 90 degrees from one another. Well, actually how can you say the first dimension is 90 degrees out from the zero dimension? You can't! Really, that works to where I'm going), i felt compelled to at least mention to others my 'insight.'

I mean if higher dimensions are 90 degrees from one another the common saying goes, then, as they say it is pretty hard to imagine(even Stephen Hawking has said this) what is 90 degrees after you get the third dimension?

I basically came to think that the fourth and higher dimensions are overlapping on one another by symmetry. Each symmetry is a higher dimension. How many symmetries a given space defined by a given shape is how many higher dimensions it can at least possibly have. I mean a cartesian plane turned 360 degrees on each other can have an infinity of dimensions of multiples of four.

Well, don't know if anybody has ever thought of this, so I posted it!

2. Apr 15, 2007

### flashgordon2!

I was a bit hesitant to post this because just stating the above doesn't give much to do or functionality; i mean, even if I'm right, so what? Well, just looking at the list of threads below, I noticed 'complex numbers', and I immediatelly see one way of making this insight fly . . . complex numbers are the arithmetic of higher dimensions according to my 'theory'!

Complex number at least in one explanation based on polar coordinates of moving the cartesian plane at 90 degrees successively.

From here, I can bet that many people here even can take this idea pretty far indeed!

3. Apr 16, 2007

### Data

Yes, it is difficult to make visual representations of four-dimensional objects in 3- or 2-dimensional space (though it is certainly possible - see tesseracts and, for that matter, penteracts), and is quite perilous to try to visualize higher-dimensional objects; However, the arithmetic and theory of such spaces is straightforward, and is presented in any introductory linear algebra textbook (for vector spaces).

What is a "symmetry"? What does it mean for a symmetry to be a higher dimension? How do you define the number of symmetries belonging to any given space? What does it mean to 'turn a cartesian plane 360 degrees'?

It is important to realize that mathematics is not a subject of idle speculation. It does not mean anything to have an idea unless you can present it rigorously under some set of axioms and with specific definitions. The subject of vector spaces of all dimensionalities is very well-understood (including the theory of infinite-dimensional spaces, which are critical to quantum mechanics and to solutions techniques to the equations describing myriad physical systems). If you want to learn about the mathematical representations of these objects (which are the same ones used by physicists and everyone else working in science), then you need only to take a few textbooks out of a library and work through them.

Complex numbers are not "the arithmetic of" anything. The set of complex numbers can be represented as a two dimensional real vector space, or (trivially) as a one dimensional complex vector space. They have nothing to do with the Cartesian plane (though the complex plane is certainly very similar to two-dimensional Euclidean space!). Polar coordinates simply provide a different way of representing a complex number; it is not difficult to show that for any real $x$ and $y$, there are some reals $r>1$ and $t, \ 0 \leq t < 2\pi,$ with $x+iy = re^{it}$.

Unfortunately, the presentations of mathematical ideas in typical popular science books are uniformly reprehensible. Do not take such presentations too seriously; Almost without exception they bear only superficial resemblance to the actual mathematical descriptions of systems. If you really want to understand the structure and power of modern science, the only way to do it is to work through the math.

Last edited: Apr 16, 2007
4. Apr 16, 2007

### flashgordon2!

there's reasons why Newton gave up talking to anybody about anything; well, at least crn chooses life;

5. Apr 16, 2007

### Data

If you think you've come up with something new, I encourage you to write it up in some cogent form. I'll be happy to read it!

I am just trying to warn you that unless you spend some time with real mathematical and physical literature (in the form of textbooks, published articles, whatever! talks and seminars are also good opportunities), your view into how science and mathematics actually work will be extremely limited. Pop science books simplify things to the point of uselessness the vast majority of the time.

While Newton was busy "not talking to anyone about anything," he held a celebrated professorial position at Cambridge, and was consulted by numerous experts in various fields on all sorts of problems.

Last edited: Apr 16, 2007
6. Apr 17, 2007

### flashgordon2!

7. Apr 17, 2007

### HallsofIvy

Staff Emeritus
Whose concerns are you referring to?

Oh, and did you note that the website you give pretty much flatly contradicts your original post?

8. Apr 17, 2007

### Hurkyl

Staff Emeritus
This is a mathematics forum. It's for discussing mathematics. If you want to learn some mathematics, then by all means stay and ask questions and listen to the advice you get. But if you want make up your own private meanings for technical words and spout oracular wisdrom, then please go elsewhere.