Purple has always been my favorite color. But purple's not just pretty--it's a special type of color. If you look at a rainbow, you won't see purple. That's because purple is what we color scientists call a 'nonspectral' color. 1/n
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Read more about it in the paper: pnas.org/content/early/…
and Princeton University has a story here: princeton.edu/news/2020/06/1…
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