## Dear Dr. Einstein Q&A

**Dear Dr. Einstein:**

How come mathematics can describe reality so well?

**Dear Serena:**

It’s hard to escape the feeling that beautiful mathematical formulas have an independent existence and an intelligence of their own. That they are wiser than we are. That we get more out of them than we originally put into them.

Eugene Wigner remarked on this phenomenon — the “unreasonable effectiveness of mathematics” in describing the natural and physical world. He said “The miracle of the appropriateness of the language of mathematics for the formulation of the laws of physics is a wonderful gift which we neither understand nor deserve”.

I added a term in my equation to produce some kind of repulsive gravitational force to keep everything in a steady state. Ironically, once Hubble discovered that the Universe is expanding, we found that the constant added as a “blunder” at the time turned out to be prescient, in that it became needed to produce what is now called “dark energy” of repulsion which makes up about 85 percent of the observable mass-energy of the Universe! What I thought was a blunder turns out to be profound. The joke is “I was wrong once; on that occasion I said I was wrong and I was right”.