I believe in (string theory) 26 space time dimensions ( bosonic string), and 10 for super strings with G2 holonomy and hadrons, with gravity acting as the force of electromagnetism and electrostatic being the force of energy that stratifies randomly due to the gravitational pull.
Of course in theory spirits or ghosts are thought to be made of and or carry electromagnetic energy as well as produce it, which deeply matches and makes sense with quantum chromodynamics, and kinetic energy.
The part that perplexes me is that most all "higher" level beings we ourselves use energy for our brains, heart ect. which is connected to electric and magnetic occurrences in our environment, which strangely are only stronger in our environment during the day and when weather is calm, with exception to electrical storms or powerful storms ( mostly holds true on areas with lime stone or highly conductive minerals), and yet, most paranormal occurrences are noticed at the night hours ( which in theory could be daylight in the other dimensions (?)) or may not be relative to other dimensions as the space constantly contracts-expands and turns depending on gravitational pull.)
I highly believe that after out bodies expire the energy does move on, energy rarely expires and usually turns into energy of something else, whether consumed or expanded, so the possibility to move through dimensions which of itself are made of energy themselves is very probable.
So in simple terms
I do believe there is a parallel universe, not in our physical sense but in more or a metaphysical sense that cannot been seen with the naked eye, dimensions and planes.