# There is no “Fourth” dimension

Everyone knows the three dimensions, but do they really exist? Here is a quick explanation of why the fourth dimension is impossible to perceive.

### 1 thought on “There is no “Fourth” dimension”

1. In my opinion two many of minute physics videos are simply about definitions. The questions in this video just comes from the fact that dimensions are not in general strictly defined.

Many of the videos creates more confusion that clarification.

Lets say I have a physical system that behaves linear in three variables, for example mass, acceleration and electrical charge. I can describe this using linear algebra, defining a vector space of three dimensions, maybe R^3. Then I might add a fourth dimension, for example time, clearly time is not among the first three dimensions.

Actually minute physics is talking about the same when they are going on about that with oil and water, two different things.

But does it change when we have things that can not be distinguished from each other?
I can have four red balls that are completely equal. Still if I pick one of them up after the other it makes perfectly sense to speak of them as the first, second, third and fourth ball, as to the order I draw them. The only problems is that if I mix all the balls together again I have no way of distinguishing among them. Drawing the balls one more time may not give the same order.