This is interesting. As a non-physicist, one sentence in particular was startling to me. "From here we will start scaling the source down using this technique

This is interesting. As a non-physicist, one sentence in particular was startling to me. "From here we will start scaling the source down using this technique until we reach the quantum world on both sides." How does this work? Do the laws of physics scale from the "big/classical" world into the quantum world as you just make things smaller? I guess I thought there must be boundaries where there were abrupt changes.