Time is generally the fourth dimension, but in the quantum world it can go forwards and backwards. Check out http://www.whatthebleep.com/rabbithole/ you have PhD physicist discussing this same thing.

Don't label it as xx dimension. We shouldn't even associate the word dimension with it because that may limit our ability to understand it. But, there are other "levels" of understanding (measuring if you like) the world (universe, add what you like here because you should never limit your mind). Watching Criss Angel, the mind freak, recently has opened mind to the fact that I don't know all what is going on around me.

I don't know the answers, but I now realize that I can influence/change the world around me. I am nowhere near mastering it, but it is better than thinking I am at the fate of the world around me. I never tell anybody how to think, but I am always trying to open my friends minds to the possibilities of what they can do.