Why is a Planck’s length the smallest possible distance?

Question

I know it’s only theoretical, but why couldn’t something be just slightly smaller?

In: 658

Answer 1

Our current understanding of the laws of physics break down at dimensions below Planck scale so we classify that as the smallest measurable distance. Of course you can say half a Planck but we really don’t know what goes on at that scale.

Here is my favorite way to visualize just how small a Planck length is. Theoretically you could fit more cubic meters into the known observable universe than you could fit cubic Planck lengths into a cubic meter.