(due to the large N ). As such, one would expect to use the k VSC (Eq. 2 or Eq. 10) to describe the rate constant associated with a single molecule, add up all contributions in FGR and normalize it with 1/N (to avoid a simple concentration effect). This, however, will not give any significant change in the VSC-modified rate constant , due to the large 1/N normalization factor. Future work needs to address this challenge, which might emerge from non-trivial collective effect due to non-local collective light-matter coupling .