Just wondering since I was watching the Twilight Zone Marathon. Hearing Rod say “there is a 5th dimension” long enough got me wondering exactly what are all the dimensions and how many are there? Are there unverified dimensions as well as one we have scientifically verified?
I plan on knocking out Dr. Who and stealing the Tardis so this may be valuable information.
Last I checked, the physicists and mathematicians were talking about 42 dimensions of space, but it all depends on which cosmology you believe in.
That 42 was the minimum amount wasn’t it? I think they just concluded that 41 was not enough.
Douglas Adams is vindicated!
I dunno about the other 37 or so, but the first four are: length, width, height, and time… 2 of them we have pretty good control of, the third we have some control of, and the fourth (time) we can only sit back and watch as it passes by (and maybe have a little control over how fast it passes by means of velocity and subjectivity)… the rest of them we have no direct way of controlling or perceiving!
Isn’t that weird!?! Our universe has, maybe, 42 dimensions, and we can only see 4 of them!
Lots of shit happening out there that we can’t see… creepy!
I may be off a bit as it is Monday and my brain isn’t firing but IIRC String theory postulates 10 or 27 dimensions. If they do the math with any other number of dimensions it doesn’t work.
Also, you need to distinguish between spacelike dimensions and timelike. Einstein’s theories have four dimensions: an X, Y and Z coordinate (setting your place in physical space) and time. I.e. I’ll meet you on the 90th floor of the World Trade Center (definable by an X, Y and Z coordinate) at 10 a.m. (when the event will occur).
So, I guess it depends who you ask. Sting theory is on the track of the Grand Unification Theory (GUT). Einstein’s theories (the very big things) and quantum mechanics (the very small things) sit at opposite ends of a spectrum and it can be difficult to make them agree when they meet. String theory shows that quantum theory and relativity can be merged when using higher dimensions (as you work the math backwards from 10 dimensions relativity and quantum theory spit back out). Basically, there is enough ‘room’ in 10 dimensions to accomodate both theories.
However, while the math may work nicely in 10 dimensions I do not know if that agrues there actually are 10 dimensions or whether it is nothing more than a mathematical trick. Also, as I understand it, the math for String theory is quite complex and they are still working on it. Someone once said that they have a theory (String) but not the mathematical skills/techniques to explore it fully and may not for years to come. Usually people come up with the math first and then postulate new theories that the math suggests so the String theorists have it a bit backwards in this regard.
Heath Doolin, I think this is one you should search for because we talked about it a lot before & its going to become a debate…
Also, there are fractional dimensions. They come up in mapping coastlines and in certain “geometrical” figures that manage to cover like a square (two dimensional) with only a meandering line, and thus are something like 1.89 dimension.
See Mandelbrot for details. When you read about it it is easy to understand, wherease dimensions over 3 aren’t.
There are four dimensions.
Time, macrospace, microspace and perception (mind).
This very question has been answered by our very own Straight Dope Staff, specifically Karen and Dex. Read up.
The term dimension is also used for all the variables in a situation, for instance in weather there are the dimensions of pressure, temperature, velocity, humidity, and so on.
You can make a multi-dimensional diagram of all this,so to speak.
Think of it this way. Take a 0 dimensional object: the point. Now, take another one somewhere else in space. Fill in all the area between those two 0 dimensional objects and what do you have? a 1 dimensional object, the line.
Now, take that line. Create an equal line somewhere else in space parallel to that original line. Fill in all the area between those two and you have a 2 dimensional object: the plane.
Do the same thing with the plane. You get a 3 dimensional object similar to a cube.
Now, continue that logic onward past a cube and you have your 4th dimensional object. The problem breaks down here because you can’t visualize a 4 dimensional object. That’s the main problem. Not that it doesn’t exist, but that you can’t see it.
You can’t actually draw cube on a piece of paper…but people still try to every day. The reason why is that we visualize 3 dimensions and so we understand what you’re drawing is 3 dimensional even though it’s clearly being shown on a 2 dimensional surface. You can draw a 4 dimensional object on a piece of paper, or a 5, or a 6, up to infinity. But when you stop understanding what the drawing represents, the number of dimensions becomes meaningless.
(boldly stating the obvious while skirting the question…)
There are as many dimensions as you need.
Physics can be considered as a standardized set of tools for describing the real world, much as a map is a tool that represents a physical space. Do you need to describe changes of some type or another? Add a dimension.
I assume that the 42 dimensions refers to a standard set of independent (“orthogonal”?) dimensions, but I have never seen them listed. Anyone have a list or link?
What about the Hausdorf Dimension or Space, Banach Space, and Hilbert Space? What kind of spaces are these that I keep hearing about? Are they dimensions beyond our ken?