The internet is stuffed with online quizzes and surveys, ranging from which “Friends” character you are to who you’re about to vote for.

But the BBC recently asked something more profound of its readers: What is the most beautiful equation ever written?

Scientists and mathematicians told the BBC that the Dirac equation (see below) takes the cake.

“Aesthetically, it is elegant and simple,” physicist Jim Al-Khalili told BBC Earth. “This equation is very powerful, mainly because of what it signifies and the role it played in the history of 20th-century physics.”

So far, readers agree with more than a third of their votes.

Here’s why that may be, with explanations behind two of the top runners-up for “prettiest equation.”

The Dirac equation

### dirac equation

Dirac’s equation married Einstein’s special theory of relativity, concerning behavior of objects at light speed, with quantum mechanics, which describes the activity of very small particles.

By finding the equation explaining how electrons spin when they approach light speed, Dirac made the first steps in what we now know as quantum field theory and predicted the existence of antimatter.

Apparently when Dirac himself was asked about his equation, he answered, “I found it beautiful.”

And apparently, the BBC’s panel of readers and scientists agrees.

Euler’s identity

eulers identity

Public domain via LiveScience

This equality of identity by the Swiss mathematician known as “the Mozart of Mathematics,” looks much simpler than Dirac’s. But in its apparent simplicity, Leonhard Euler managed to capture some of the most basic principles of mathematics (as well as 17% of the vote).

The equation contains the five most important numbers in math — 1, 0, pi, i, and e — with the three basic operations that give math structure: Addition, multiplication, and exponentiation.

In case you need a refresher:

The letter “i” stands in for an imaginary number, the square root of -1; while “e” is a mathematical constant approximately equal to 2.71828 — but, like pi, it’s irrational.

There’s definitely something satisfying in its simplicity. It also happens to be hugely important to basically every field of math.

### Pi

This is probably the contender you remember best from high school. It describes the ratio of a circle’s radius to its circumference. Again, it’s irrational, but roughly equivalent to 3.14159. See?

We can trace rough calculations of pi to the ancient Babylonians — roughly 4,000 years ago — but it’s still incredibly useful. It helps us discover planets, launch spacecraft, and even appears in the double helix of DNA.

“I tell my students that if this formula doesn’t completely blow them away then they simply have no soul,” mathematician Chris Budd told BBC Earth. “It can be used to describe the geometry of the world.”

And really, that’s what all of the most beautiful equations share: While they might seem complicated (looking at you, Dirac), they describe simple mathematical truths already present in the world in human terms.

And what’s more beautiful than that?

This article has chosen from here

Nicely compiled! My vote goes to the Euler’s identity!

sometimes some mystery-like things happen in science. one of them is the Euler’s equation. one another is E=MC^2

Reblogged this on Mathpresso.