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Posted by: Venator82
Space is what we call the third dimension, and time is what is called the fourth dimension, however time is present in the 1st, 2nd, 3rd, all dimensions or they would not exist in a way we can percieve, which we know they can. But if time were a dimension, then every other dimension would instantly be bumped up to 4th dimension, which they are not.
This means time is not a dimension,
There seems to be general confusion as to what dimensions actually are, which is an issue that everyone has trouble with when thinking about higher dimensions, myself included. Sometimes we need to go back to basics. I'll try to keep the formulas themselves simple, though I'm going to have to jump up to 4-dimensional mathematics in order to generalize all the way past the spatial dimensions and to time.
You've concluded that time, being a separate dimension, should not have effects in the 3 spatial dimensions. You're effectively claiming that things in the 3 spacial dimensions should not change with respect to time. To point out why this is wrong, let's consider how the lower dimensions affect each other.
Imagine that you have a simple two-dimensional graph with a y and an x axis, for two of the spatial dimensions. Now imagine that there is an object drawn on the graph, let's say it's a parabola given by y=x^2. Now, let's say you have a piece of paper with a long, thin slit in the middle, and let's say you lay this slit along the x-axis of the graph, such that the slit's current height is at y=0. Right now, you can see the part of the parabola that touches at x=0.
Now, move the slit up on the y axis to y=1. What does the parabola object look like now? Through the slit, you can now see a point at x=-1 and another at x=1.
If you move the slit up to y=4, you will be able to see that there is a piece of the parabola at x=-2 and x=2.
So, for a viewer that can only see the x-value of something (a viewer who is looking through the slit), objects in their view change as values along the y-dimension change.
Let's go yet another step and assume that the parabola was, this entire time, a 2-dimensional slice of a circular paraboloid existing in an X, a Y, and a Z dimension, and given by the formula y=x^2+z^2. Suppose that the 2-dimensional graph from before was nothing but a cutaway of this function given for when z=0 and thus on the 2-d graph y=x^2+0^2=x^2.
Suppose that we look at the 2-dimensional slice for when z=1. Now, our 2-dimensional graph looks like y=x^2+1, which means changes in the z-dimension are having effects in the 2-dimensional plane. These effects will also manifest themselves at the 1-dimensional slit level; our through-the-slit observer will now be shocked to find that, at y=1, there is only one point of the parabola, and it exists at x=0!
So, as the z-value changes, the situation in the x-y plane and thus also the lowly x line change with it.
Now suppose we assume that this circular paraboloid is moving in the y-direction at a speed of 1 y-unit per time-unit. Thus, we can write our generalized formula for the paraboloid as y=x^2+z^2+t. Now suppose that we look at this from the perspective of a viewer who fully perceives 3 dimensions.
At t=0, this viewer will see the simple paraboloid y=x^2+z^2. But at t=1, he will see y=x^2+z^2+1.
This effect propogates lower, as well. If we look at this from the 2-d x-y plane perspective, the graph at t=0 is y=x^2, but at t=2 it's y=x^2+2.
And again, at the lowly x-slit perspective, things change as time changes the parabola being viewed by the slit.
So, time really does behave a lot like the spatial dimensions do; changes in y affect what a viewer who sees only the x-values sees, changes in z affect what a viewer who sees an x-y plane sees, changes in t affect what a viewer who sees an x-y-z volume sees, and all of these changes propogate down to the levels below them.
Hopefully this makes sense.
tl;dr: The changes cause by time in the spatial dimensions are very similar to the changes cause by higher spatial dimensions to lower ones. Viewing the changes of objects in a spatial dimension with respect to time is not much different from viewing changes in a cross section as it moves forward through a spatial object.
[Edited on 01.19.2011 4:37 PM PST]