Get 3 sticks, try and arrange them all perpendicular to each other. You can do it. Now try with 4, you can’t. We live in 3D space.
Time is a line, at least as we experience it. Just one, it’s hard to even figure out what 2D time would mean, although physicists have thought about it.
So, 3+1=4. It turns out they’re kind of interchangeable, though, in that swapping time for a kind of angle made up of some space and some time, if done in a certain way, leaves the predictions of physics the same. That’s special relativity, and it is itself connected to the way everything is a wave.
If I had to guess, what you’re referring to is how higher dimensions are “orthogonal” (at right angles) to the dimensions below it.
How can you arrange 3 sticks orthogonally using 2 dimensions of space?
The same idea can be applied to arranging 4 sticks orthogonally using 3 dimensions of space.
Maybe to a flatlander, a theoretical being that only experiences 2D space, they’d have a different word for the third dimension like we have a different word for the fourth. That wouldn’t mean the third dimension isn’t spacial.
Soo what are you wondering? I’d expect it’s obvious in our everyday experience that time is a bit different from space.
If you want a something more mathematical, pick an equation from physics. It probably treats time separately from space. The only kind-of exception I can think of is general relativity, and even it ends up producing metrics that give time the opposite sign, like the flat space example the other poster mentioned.
The directionality of time is a bit more subtle and emergent, but you don’t need it to look at a double light cone and observe that while a slice of it is a sphere, the whole thing is not a hypersphere. That just follows from Maxwell’s equations or the other wave equations in nature.
If somebody here knows their way around QFT they might have something to add, but for all the rest it’s just kind of built in.
Get 3 sticks, try and arrange them all perpendicular to each other. You can do it. Now try with 4, you can’t. We live in 3D space.
Time is a line, at least as we experience it. Just one, it’s hard to even figure out what 2D time would mean, although physicists have thought about it.
So, 3+1=4. It turns out they’re kind of interchangeable, though, in that swapping time for a kind of angle made up of some space and some time, if done in a certain way, leaves the predictions of physics the same. That’s special relativity, and it is itself connected to the way everything is a wave.
If I had to guess, what you’re referring to is how higher dimensions are “orthogonal” (at right angles) to the dimensions below it.
How can you arrange 3 sticks orthogonally using 2 dimensions of space?
The same idea can be applied to arranging 4 sticks orthogonally using 3 dimensions of space.
Maybe to a flatlander, a theoretical being that only experiences 2D space, they’d have a different word for the third dimension like we have a different word for the fourth. That wouldn’t mean the third dimension isn’t spacial.
Soo what are you wondering? I’d expect it’s obvious in our everyday experience that time is a bit different from space.
If you want a something more mathematical, pick an equation from physics. It probably treats time separately from space. The only kind-of exception I can think of is general relativity, and even it ends up producing metrics that give time the opposite sign, like the flat space example the other poster mentioned.
The directionality of time is a bit more subtle and emergent, but you don’t need it to look at a double light cone and observe that while a slice of it is a sphere, the whole thing is not a hypersphere. That just follows from Maxwell’s equations or the other wave equations in nature.
If somebody here knows their way around QFT they might have something to add, but for all the rest it’s just kind of built in.
Huh?
I can align as many sticks parallel to each other as I want.
Shit. Fixed.
deleted by creator
Ah, makes more sense now. Haha