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Thursday, March 01, 2018

Equations That Changed the World

A few years ago, mathematician Ian Stewart published a book titled 17 Equations That Changed The World. It's an interesting list:


I would go beyond these 17 and add: 
  • 1+1=2, which some unknown someone realized long ago was profound and incredibly useful. The logical proof of this assertion, though, didn't come until Bertrand Russell and Alfred North Whitehead three-volume Principia Mathematica. It's a crazy book -- the text looks almost alien or elvish, and it took them several hundred pages of work before they could prove that 1+1=2. Russel said his work on this book "had actually damaged his brain." Here's an interesting discussion of the Principia Mathematica from NPR in 2010.
  • Newton's second law of motion, F=ma (really, F=dp/dt, the time rate of change of momentum).
  • Planck's Law of radiation (probably).
  • The Lagrangian of quantum electrodynamics, because it changed how quantum physics was done ever afterward.
  • Einstein's equations of general relativity, because they changed our view and understanding of the universe, and for their sheer elegance and sophistication. 
You?

5 comments:

  1. This one ties three familiar numbers together: https://www.math.toronto.edu/mathnet/questionCorner/qc_hlimgs1/image142.gif
    ..
    May not have changed the world, but is simply elegant.

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  2. Thanks, CJ. If you write this equation as exp(i*pi)+1=0, it ties five important numbers together....

    ReplyDelete
  3. Mean (aka Arithmetic Mean, Average) = The sum of all of the numbers in a list divided by the number of items in that list.

    Also, the variance and standard deviation
    (sorry, I don't know an easy way to paste the formulas here)

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  4. I would replace the Black-Scholes equation with the Fokker-Planck equation.

    The former is a recasting of the latter so it can be used in economics.

    The latter is primarily responsible for semiconductor electrical transport modeling.

    ReplyDelete