Infinite Space is the 4th Dimension (in my opinion)
My theory is that since we live on earth (a 3dimensional object) we're never exposed and therefore cant really comprehend a 4th dimension....but if the fourth dimension was an extension of the 3rd dimensions, in the same way that 3d is an extension of 2d...then it would extended infinitely.
that probably sounds confusing, so i will use an example to clarify my theory of why the 4th dimension is infinite space.....
Ok, lets say that the planet earth represents 3 dimensions (just like a drawing of a cube represents 3d)....well if the 4th Dimension was an extension of a 3 dimensional space...then it could never have an end BECAUSE if it had an perimeter it would just be 3D.....Just like if we extend a drawing of a cube and try to expand it into a drawing of a hypercube, as soon as you outline the perimeter it becomes a 3D object... no matter how many overlapping squares and diamonds it forms, a tesseract drawing is a 3D DRAWING....therefore, if 4d is an expansion of 3D, there can be no outline, no perimeter, and no limitations....which brings me back to my original thought, when i said earth represents 3D (ala cube) then outerspace which is probably infinite is the 4th Dimension........no limits, no end....we cannot really grasp 4D because everything we see and create in this world has a limit (making it below 4D)...we can build the tallest sky scraper, we can swim the largest river, or climb the highest mountain....but all those things have ends....everything spacial we know of has a limit.....except for outerspace which goes on infinitely....making it not 3D but 4D
so to summerize my theory....outerspace is the only known 4D that exist...in scifi movies we may see fictional 4D things, such as a bottomless pit for example...however no true 4D exists to us in this 3D world....if we understood and conquered the secret 4th Dimension....we could build worlds within worlds (like the game myst)
perhaps dreams are also a form of 4 dimensions, because there are no limits as far as we know.
well thats my opinion, thank you for reading it