Maybe monochromatic is not the right word, what I mean is light consisting of a single wavelength (i.e. a spectral color) versus light composed of photons of multiple wavelengths (intermediate color).
Is it possible to combine the latter light sources such that their composite would perfectly match the violet one such that both look the same to a human eye (assuming perfect alignment)?
And would they look the same to all human eyes?
My guess is a no, because people might have different susceptibility to red and blue hues, and their aggregation functions may differ as well.
* Apparently, there are alternative definitions to distinguish the two colors (purple is reddish, violet bluish), but I am referring to the ones found in Wikipedia: Purple being an intermediate color and violet being a pure spectral color.