I believe it could be possible (just a guess) to manipulate the
different dimensions and access the past or the future in
consciousness, just as certain clairvoyants and psychics may
achieve such feats. My Shi Fu actually once looked into a building
and all the visions and images of the entire building's past, who
build it, when was it built etc spontaneously manifested to him. He
asked those around him to look and it will reveal, but even
Missionary Chen could not understand him at that time. In another
instance, in one of his dharma talks, he said that 'there is
something very strange and amazing' - that we can all access the
past in a few hundred years time (advanced technology?) and
everything that is said in this talk will be seen (not by audio and
video but literally like "accessing the past")
However the dharmadhatu is beyond all space, time, dimensions, and
also pervades all space, all time, all dimensions.
Buddha abides in the infinite,
the unobstructed, ultimate realm of reality, in the realm of space,
in the essence of True Thusness, without birth or death, and in
ultimate truth, appearing to sentient beings according to the time,
sustained by past vows, without ever ceasing, not abandoning all
beings, all lands, all phenomena....
How should enlightening beings see the body of Buddha? (Dharmakaya)
They should see the body of Buddha in infinite places. Why? They
should not see Buddha in just one thing, one phenomenon, one body,
one land, one being--they should see Buddha everywhere. Just as
space is omnipresent, in all places, material or immaterial, yet
without either arriving or not arriving there, because space is
incorporeal, in the same way Buddha is omnipresent, in all places,
in all beings, in all things, in all lands, yet neither arriving
nor not arriving there, because Buddha's body is incorporeal,
manifesting a body for the sake of sentient beings.
- Garland Sutra
I think all dimensions from 1 to 10 are based on relativity. Anyway
I have no experience to verify this, but just find it
interesting.