Yes I do believe it exists. I have seen things I can't explain. I have seen energy the size of a huge beachball when someone has astral travelled to my house. I have astral traveled and I have seen spirits in my house later to have them expound on certain issues by others that I know.
WE have more abilities than what we currently know about. We are just touching off the tip of the iceburg.
The book of Thomas talks about the other realm. The book of Enoch talks about his intercession with God on behalf of the fallen angels.
We believed in God who we could not see, we believe in demons who we could not see. Why don't we have faith in things that can truly affect us for the good. Why are we willing to believe in things that are bad but unwilling to see a higher energy for the good of all mankind?
Yes, Yes, Yes. Even if we can't measure now doesn't mean in the future it will be non existant.
Cathy