I don't know about the 4th, but the 5th dimension were Diana Ross' cohorts!!!!!!

Time is one of them.

American R&B group late 1960's. Aquarius/Let the sun shine in!

1) "In physics and mathematics, a sequence of n numbers can be understood as a location in an n-dimensional space. When n=4, the set of all such locations is called 4-dimensional space, or, colloquially, the fourth dimension. Such a space differs from the familiar 3-dimensional space that we live in, in that it has an extra dimension, an extra degree of freedom. This extra dimension may be interpreted either as time, or as a literal fourth dimension of space, a fourth spatial dimension." Source and further information: http://en.wikipedia.org/wiki/Fourth_dimension Of course, this could be extended to any number of dimensions. 2) "To understand the nature of four-dimensional space, a device called dimensional analogy is commonly employed. Dimensional analogy is the study of how (n – 1) dimensions relate to n dimensions, and then inferring how n dimensions would relate to (n + 1) dimensions. Dimensional analogy was used by Edwin Abbott Abbott in the book Flatland, which narrates a story about a square that lives in a two-dimensional world, like the surface of a piece of paper. From the perspective of this square, a three-dimensional being has seemingly god-like powers, such as being able to remove objects from a safe without breaking it open (by moving them across the third dimension), being able to see everything that from the two-dimensional perspective is enclosed behind walls, and remaining completely invisible by standing a few inches away in the third dimension. Another example of this concept is seen in the Wii Video Game Super Paper Mario, where the protagonist is able to shift from a two-dimensional perspective to a three-dimensional one. By applying dimensional analogy, one can infer that a four-dimensional being would be capable of similar feats from our three-dimensional perspective. Rudy Rucker demonstrates this in his novel Spaceland, in which the protagonist encounters four-dimensional beings who demonstrate such powers." Source and further information: http://en.wikipedia.org/wiki/Fourth_dimension 3) "Theories such as string theory and M-theory predict that physical space in general has in fact 10 and 11 dimensions, respectively. The extra dimensions are spacelike. We perceive only three spatial dimensions, and no physical experiments have confirmed the reality of additional dimensions. A possible explanation that has been suggested is that space is as it were "curled up" in the extra dimensions on a subatomic scale, possibly at the quark/string level of scale or below." Source and further information: http://en.wikipedia.org/wiki/Dimension#Additional_dimensions 4) "In metaphysics and esoteric cosmology, a plane, other than the physical plane, is conceived as a subtle state of consciousness that transcends the known physical universe. The concept may be found in religious, metaphysical and esoteric teachings - e.g. Vedanta (Advaita Vedanta), Neoplatonism, Gnosticism, Kashmir Shaivism, Sant Mat/Surat Shabd Yoga, Sufism, Druze, Kabbalah, Theosophy, Anthroposophy, Rosicrucianism (Esoteric Christian), Eckankar, Ascended Master Teachings, etc. - which propound the idea of a whole series of subtle planes or worlds or dimensions which, from a center, interpenetrate themselves and the physical planet in which we live, the solar systems, and all the physical structures of the universe. This interpenetration of planes culminates in the universe itself as a physical structured, dynamic and evolutive expression emanated through a series of steadily denser stages, becoming progressively more material and embodied." Source and further information: http://en.wikipedia.org/wiki/Plane_(metaphysics)

I think generally speaking the fourth dimension is considered time. However String Theory would suggest there are 10 dimensions.

8-29-2017 There are three physical dimensions. Anything else is imaginary. If there were a fourth physical dimension, knots would not stay tied and blood would not stay in arteries.