what is the "density" exactly means?

[zenmaster]

my problem is, we dont have anything to conclude that noncolliding approach. the control attachment, may be a valid attachment. but, it doesnt explain or justify the noncolliding approach.

There are certainly problems. Obviously, I'm not prepared to give a full philosophical treatment, to say nothing about a working physical theory that may or may not satisfy doubts. I personally know a few people that are capable of providing a better explanation (in practical, mechanical terms), but I doubt you will see such information soon. Not sure if this review helps, but:
. The levels of control theory/speculation allows for collision (or any type of interaction).
. We know that 3d and 4d can have complete material/local (space/time) integration and compatibility (no collision) via natural processes. This is in the form of the dual-activated entity (body and mind) and the body and mind layer of the planet.
. 3d and 4d material can only have the potential to collide if they are in proximity. However, only yellow ray 'matrix' allows for the initial manifestation of 3d (natural process of birth). Therefore, a 3d entity can only be in a total 4d environment if the 3d entity lives (long enough) through the transition to 4d (i.e. genetic engineering)
. Because natural processes always produce compatible 3d and 4d manifestation, and because 3d cannot manifest 4d material, any collision would be the result of a 4d's entity's will. Apparently early 4D don't understand how their bodies are manifested, but can learn to control this manifestation (at least at 3d level) through their volition. This 4D learning apparently takes a long time.
. There is a thread on another forum about a 3d entity and 4d entity interacting. the 4d entity knows that if she were manifest in her 4d body before the 3d entity, it would basically destroy the 3d entity (due to collision).