Someone clarify me.how many dimensions does tobi posses?.if one can't kakashi access it?.where he transported nagato's body when he first found it,that dimension?
their both the same dimension
kakashi eye simple absorbs things into that dimension whilst tobi is allowed to transport his body to that other dimension.The relationship between dimension means that they have similar eyes.
i believe it is only 1 dimesion because if he had more then 1 then after the kunai hit he would have known what happened so he would have transfere to a different dimesion so id say 1 =)
Kakashi is not an uchiha so he may just not have the stamina and chakra reserves. Also maybe only the right eye can do those things. Tobi can't use kamui, if he could he would have used it by now.
I don't think being a Uchiha has anything to do with it. It has previously been stated that only a Uchiha can unlock MS, and Kakashi proved that wrong. Either he needs more time to develop it or in order to fully manipulate the that dimension you need both eyes.