Topic: Dimensions:

I know there are clever ideas about multiple dimensions but I always wonder why there would be a need for more dimensions than what we live in?

If these speculative dimensions exist and if they overlap our own dimension, what purpose are they intended to serve? What about conservation of energy and matter and gravitational effects of multiple sources of gravity occupying the same space. Or, possibly we should look for these other dimensions adjacent to our own so there are no conflicts with known physics. Possibly each secondary dimension will consist of stuff as far removed from reality as we know as the conception itself is.

My point; What is the motivation for conceiving of multiple dimensions?
jjw