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Per definition, in that theory, a cube is a mathematical object of which the components (i) are elements arbitrarily chosen in a set K and (ii) are situated at each knot of a three-dimensional Euclidean crystalline cubic structure.
More precisely, they are involve in procedures deforming the classical tensor products.
For example, the set of all cubes with knots in C (the set of all complex numbers) acting on elements in E(D, C) is denoted ⊞(D, C). Any cube in that set contains at most D . D . D = D3 knots.
A given cube is "symmetric" when its nodes have the proprety:
∀ α, β, χ:
Aχαβ - Aχβα = 0
The subset of all symmetric cubes is denoted ⊞+(D, K)
A given cube is "antisymmetric" when its nodes have the proprety:
∀ α, β, χ:
Aχαβ + Aχβα = 0
The subset of all symmetric cubes is denoted ⊞-(D, K).
A given cube is "reduced" when its nodes have the proprety:
∀ α, β, χ:
Aχαβ - Aβαχ = 0
The subset of all symmetric cubes is denoted ⊞↑(D, K).
A given cube is "reduced" when its nodes have the proprety:
∀ α, β, χ:
Aχαβ + Aβαχ = 0
The subset of all symmetric cubes is denoted ⊞↓(D, K).
1) Symmetric and reduced cubes are compatible:
Aχαβ = Aχβα = Aαβχ = Aαχβ = Aβχα = Aβαχ = Aχαβ
2) Antisymmetric and anti-reduced cubes are compatible:
Aχαβ = - Aχβα = Aαβχ = - Aαχβ = Aβχα = - Aβαχ = Aχαβ
3) Symmetric and anti-reduced cubes are null.
4) Antisymmetric and reduced cubes are null too.
It should be kept in mind that any element of ⊞(D, K) is equivalent of a superposition of D elements in M(D, K); therefore:
1) A symmetric cube is an element in ⊞+(D, K) which is the the superposition of D symmetric elements in M(D, K); each of them contains:
D terms along the diagonal
D - 1 terms in the first line
D - 2 terms in the second line
etc...
1 term in the (D - 1)th line
Each symmetric matrix in M(D, K) has:
D + (1/2).{D2 - D) = D.(D +1)/2
terms
As a result, each symmetric cube contains:
D2.(D +1)/2 knots
2) An antisymmetric cube is an element in ⊞-(D, K) which is the the superposition of D antisymmetric elements in M(D, K); each of them contains D.(D - 1) non necessarily vanishing terms
But since half of these terms are equal to the other half up to a sign, it is more accurate to say that each skew-symmetric matrix contains at most D.(D - 1)/2 terms whose absolute value is potentially different from the others and not necessarily zero.
As a result, each anti-symmetric cube contains at most D2.(D -1)/2 effectively different knots.
Example: A byside consequence of this statement is that any element in ⊞-(3, R) contains at most 9 knots. They can be reorganized inside an element in M(3, R).