It is so simple, this is the same object seen over 2 places.
Think of a fishing tank, the side glass wall and the front glass wall show the same fish. And that's i hope an easy to understand example of an extra dimension, it solves many physics problems add a dimension..
As the fish swims in the tank, both walls show change in position to and no need for communication at all, its just one fish.
you need proof for extra-dimensional existence just take all those experiments that could be solved by it .. double split... spooky action .... and many more.. (even quantum computers inner working)
you need proof for extra-dimensional existence just take all those experiments that could be solved by it .. double split... spooky action .... and many more.. (even quantum computers inner working)