## Math Photo: Colorful Venn

This colorful Venn diagram was a lucky find in the dollar bin.  Maybe it was so cheap because it only has 12 regions, instead of the 63 that six sets should generate.

I suppose it would be more realistic if everything outside the colored region was black, and the point at the very center was white.

1. Henry Ricardo says:

The resulting color depends on whether you’re mixing pigments or light. You won’t get white at the intersection of all the colors if you are working with pigments.

2. Henry Ricardo says:

An addendum to my previous comment. This example is discussed in my book A Modern Introduction to Linear Algebra (CRC Press, 2009):

EXAMPLE 1.5.4 RGB Color Space
In terms of the perception of light by the human eye, experiments have shown
that every color can be duplicated by using mixtures of the three primary colors,
red, green, and blue 1. There is, however, a difference between mixtures of
light (as used on a computer screen) and mixtures of pigment an artist
uses.1
1 The theory was presented by Thomas Young in 1802 and developed further by Hermann von Helmholtz in the 1850’s. The theory was finally proved in a 1983 experiment by Dartnall, Bowmaker, and Mollon.
2See, for example, Chapter 6 of Digital Image Processing (Second Edition) by R. G. Gonzalez and R. E. Woods (Upper Saddle River, NJ: Prentice-Hall, 2002).

• MrHonner says:

Thanks for sharing, Henry. This sounds interesting, and I’m teaching Linear Algebra! Any online resources you might be able to point me to regarding this? I don’t have your book, or those you’ve cited.

• Henry Ricardo says:

Overlooking your negligence in not having my book ( 🙂 ), I want to provide you with a pdf document containing some material from my book and some Internet references, but I can’t seem to insert it in in this space. (Sorry that the figure is missing, but you can fill in the blank space.) Of course Fermat had much the same problem with some stuff of his. PLEASE ADVISE.

• MrHonner says:

How kind of you to excuse my negligence, and what a nice offer!