Development of Superstring Theory - A new 12-D theory combines Riemann's multi-dimensional concept of unified interactions and quantum mechanics (probabilism).

3 or 4 of these dimensions are perceivable to humans.

Perhaps the 3 (or 4) dimensions are expanding -> expansion of the universe we see

Expansion of some dimensions separate the simplicity of the unified field.

The others are hidden dimensions (at least to us anyhow).

The aspects of the many particles of the Standard Model are projections of the higher dimensions onto the 3 (or 4) we know.

High energy particle accelerators allow us to see the folds in the higher dimensional space that show up as the particles of the Standard Model.