m-theory question for n00b writer

[cassanda_complex]

Hi guys. I'm in the process of writing a novel. It is my first book and I'm in my twenties. I'm going to give it a shot because people say I have talent. In my story, the protagonist is under telepathic attack by what I describe as a "paranormal" entity, in the sense that it is beyond the scope of normal human experience and "conventional" scientific understanding, but it is not a demon, I am going to make it an alien. I am thinking about making the entity from another dimension.

 

I want to stay true to m-theory, so I have a question. Are the higher dimensions outside space/time for our dimension, in a way so that a being from one could theoretically move to their dimension, run some errands or whatever, and then come back to ours without there being a time difference in our dimension?

[cassanda_complex]

Would time go by slower from the perspective of a being from a higher dimension than ours since their dimension vibrates at a higher frequency?