Are there more than four dimensions?

The universe is described in terms of dimensional spacetime by General Relativity (GR), which gives rise to three spatial dimensions and one time dimension.

The issue is that while both general relativity and quantum theory have been proven in many ways, they cannot coexist.

In any case, the extra dimensions would have to be very small; consider a particle as a vibration along the axis of a very small dimension. The extra dimensions have no meaning in terms of space and time. String theory is one set of candidates for this, requiring the addition of six or seven extra dimensions. There is no evidence that string theory is correct.

In theories like string theory and M-theory, which are attempts to reconcile quantum mechanics with general relativity, there are additional spatial dimensions beyond the four we experience. These theories propose that the universe may have 10 or 11 dimensions in total, with the extra dimensions compactified or curled up at extremely small scales beyond our ability to detect directly.