bilglik 6

324 Bilgilik
They could not move or see in any of the other directions, and probably could not even
comprehend
such directions as even existing. Photons whizzing by them would only be visible if they
entered the singular line that was
a 1D person’s whole area of existence. Now, adding extra directions of movement is
what’s needed to move things up from 1D
to 2D or 3D. So, in theory, we can predict what we need to do if we were to jump up to
4D.
However, here we hit a snag. While it’s easy to draw a line that’s perfectly perpendicular
to a single other
line: Or to draw another line on top of both of those lines that is perpendicular to the two
previous lines: How would we draw a 4th line that’s perpendicular to all 3?
Surely such a thing is impossible! Well, within 3D space, such a thing is impossible.
The best we can do is draw approximations. For instance, it’s possible to draw an
approximation of a 3D shape on 2D paper, by doing something
like this: These lines are all 2 dimensional, but we look at this and our brain recognises
that this is a picture of a 3D shape. So in the same way, we can probably do something
similar to guess what a 4D object might look
like using just 3D lines. Mathematicians have attempted to do this, although their results
tend to be a little
confusing. Although this is mathematically sound as a basis for a 4D object, I personally
don’t
find my understanding of 4D space deepened by looking at it. So, I won’t focus on it in
this video.
There is some evidence, however, that a 4th direction exists, and that we are moving
through
it right now. That fourth direction, or dimension, is time. Einstein predicted this
connection when he linked space and time into one unified “space-time”
in his theories of relativity. According to him, time and space are two parts of the same
thing.