Gravity{ boson? } and dark energy{ boson? } appear to me to be a set of two ghost dimensions.

Dark matter may fall into similar catagory. However, fermionic matter is not same as bosonic forces, so this is partly why I do not place dark matter into same ghost dimension as gravity and dark energy, that, appear to be exact opposites of each other.

XYZ cartesian coordinate system-- ergo cube --is classical way to understand 3D{ volume } space.

M. Kaku showed the simple version of hyperspace{ dimension } as being a 45 degree volumetric--- i.e central vector inside the cube --diagonal line{ d } extending from same vertex as shared by XYZ( abc ).

The first and easiest way to incorporate a ghost dimension-- that is not a hyper-dimension ---is to consider three, 45 degree surface diagonals, between XYZ.

We could label them as small xyz, if they are at 90 degrees to each other. It it seem logical conclusion, altho I dunno.

The only other alternative, valid or not, is to say there is some dimensions outside of XYZ{ 3D volume }, and xyz{ 3D volume }.

Hyper-dimensions are dimension that are so small they are consider to be 3D dimensions that curled within the parameters of XYZ and we can say within xyz.

Going back to alternatives, valid or not, above, consider the following;

XY XZ and YZ individually, each are associated with a 90 degree angle. If were to connect the open ended points of XYZ. Once we do that we have a create a right triangle ergo 90 degrees plus two 45 degree angles.

Ex XY-T i.e. the T is for right Triangle.

The next step is to say we give XYZ and T-T-T a curvature dimension. Now we have a symmetrical circle even tho, we have two differrent angle values involved with three angles.

https://www.google.com/search?q=curv...w=1282&bih=542
If scroll to fourth horizontal line on google page above, there is a circle with right triangle.

X = 6, Y = 6, T = 8.4852813742385 See X^2 + Y^2 = T^2{ Pythagoras Rule }

r6