The Fourth Dimension is NOT time, it is a physical dimension at right angles to the first three. It is almost impossible for us three dimensional creatures to visualize it.
It depends. What you are talking about is a hypothetical spatial dimension in addition to the standard three dimensions. When scientists talk about the fourth dimension they are referring to space time not spatial dimensions. The fourth dimension in this context is time, which governs all matter at any given point, also known as four dimension Euclidian space. So he is correct in that what he is talking about is in fact time as the forth dimension.
