Does the Planck Scale Matter?

One can ask whether the Planck scale matters to our present understanding of science. One viewpoint is that we have no method to probe the Planck scale, so it is of no significance.

However, if the Universe passed through the Planck scale early in its history, it is possible that the Universe is the way that it is because of events at the Planck scale. For example, perhaps the number of dimensions in spacetime would have been different if different things had happened at the Planck time. If that were true, the Planck scale would certainly be scientifically relevant to our understanding of the Universe, even if we cannot study it directly today.