I have often wondered where we go when we sleep also; I have always been curious about time travel also. My personal perspective is that we actually have the ability to set our spirits to commune with our Creator in our waking and even moreso in our sleeping. I believe that dreams can be significant and not so much. The art form is to know the difference and seek our heavenly Father for wisdom through it all. Of course the measuring stick for any believer is how it lines up with the Word. Blessings~