if time is bothering you because people invent ways to measure it, then ordinary distance must bother you also. A meter stick is an incredibly contrived and human-based device. You could say, "well an atom is only so big, so there's length!" But the physicist says, "well, this atom typically lasts a certain while before it becomes such-and-so through radioactive beta decay, so there's time!" Make any sense?
dimensions, in some sense, just give you a way to find things. addresses. call them coordinates. So to be *really* specific, if you want to talk about, say, Cato hacking somebody... okay, not specific enough. Let's say you want to talk about a rare event: Cato goes coast to coast for a finger roll. You wouldn't want to just know space coordinates (for example, this happened maybe in Portland). That would give you X,Y, and Z. exact spatial placement in the universe. But you really want to know when! Was he a Trailblazer, or a Rocket? Was it preseason? (probably ). So you give it a time stamp. For example, September 23 of the year 2000. Now you've fully described the event. And time is a dimension. An oil tanker is long. And a millenium is long in time. Collier's vertical is small. His playing time is also small. both dimensions.
Basically time is a dimension because space and time are inextricably connected. That is why you might hear people talking about spacetime. Also connected are matter and energy. They seem like different concepts but are actually much the same thing.
I have wondered about the possibility of additional dimensions beyond 4d, in our universe. For example, if a fluid could fold back in on itself, isn't that 5d? Can't we already mimic that now? Also, if XYZ + time can describe a particular region of space, at a particular instant, why shouldn't there be other attributes or dimensions that qualify the event even more? I don't have any apt words for them - maybe like intensity, or hue, or resilience. For example, if we had the abililty to rewind time & space, and watch Cato finger roll the ball over and over again (sweet), would we be able to see other physical or environmental laws that affect the "nature" of the finger roll? mean, courteous, routine, etc....... Naturally, these additional dimensions would have to exist in all of space, at all times, coloring every event.
I think some scientists talk about up to around 20 dimensions, or something like that. I have only managed to understand the 4 though.
I believe string theory requires 12 or 13 dimensions. I don't think many people really "understand" or visualize this many dimensions, but many physicists just trust the math and make analogies. For example, let's say humans don't fly (correct before Wright brothers, more or less). So you could find most every human on the two-dimensional surface of the Earth (latitude and longitude will place them all). If the universe you were examining was just about humans, then you would only need those two dimensions, and the third (up and down) would be "extra." So, if I understand it at all, something like string theory suggests that everyday matter just needs the four dimensions (x,y,z,t), while other entities and other types of physical laws may be wrapped up in other dimensions. By the way, I am completely unqualified to judge string theory, but it is my strong opinion that the theory is way too contrived and way too untestable. Therefore, I think it's a big stinky piece of crap. Maybe it's an elegant and nicely crafted pile, but still a big stinky pile.
I think a fractal pattern can often be described by a number of dimensions in between whole numbers. This is definitely not my field, so don't take this as fact. But if you see a fractal pattern on a piece of paper, a mathematician will often rate the dimensionality as something between 1 and 2 (e.g. 1.7). It's interrelated enough to not need a whole two independent dimensions. Vaguely like a bead on a string moves all over the place, but if you count the string as just one curved dimension, the problem reduces to one dimension. Since fractals have certain rules, they're not fully random in the dimensions they inhabit. Anyone have any doubts about what a complete nerd I am now? Sheesh. I gotta get back to work.
