We are very pleased with the number of people who were interested in our latest presentation. Here are some interesting trivia about the ten equations presented.

1. **Pythagoras’ Theorem**: The square of the hypotenuse of a triangle is equal to the sum of the squares of its legs. The theorem is used in “triangulation” which is fundamental in finding your geographical position.

2. **Newton’s Universal Law of Gravitation**. They say it was an apple that fell on Newton’s head but the fact is that that several centuries later the equation is used to put objects in space, including satellites.

3. **The Normal Distribution**. it has the shape of a bell, also called “bell curve”, and was developed by French mathematician Blaise Pascal and Belgian mathematician Adolphe Quetelet. Drug research uses the bell curve to decide whether a certain drug or therapy has a benefit to most patients that take it.

4. **Fourier Transform**. Describes how patterns (e.g. information) in time evolve with respect to frequency. You can take a patter, say a photograph, break it down and analyse, which is what digital cameras do when you take a photo and store it as jpeg.

5. **The Navier-Stokes Equations**. The mathematician Leonhard Euler was fascinated with the flow of fluids so he figured out how flow related to the forces that acted upon it. French engineer Claude-Louis Navier and Irish mathematician George Stokes took it a step further. Aircraft designers use it when they design jets.

6. **Maxwell’s Equations**. James Clerk Maxwell discovered the connection between magnetism and electricity. Telecommunications are based on electromagnetic waves.

7. **The Schrödinger Equation**. He is the man who thought the Cat Experiment that gave Feline Quanta its name (see here). He is also one of the fathers of quantum physics that says that fundamental particles (like electrons) can be waves too. Miniaturised transistors in the integrated circuits of computers and mobile devices must take into account “quantum effects”.

8. **The logistic model for chaos**. Originally it was used to predict how a population may fluctuate over time given limited resources. Then people realised that the equation described all kinds of “chaotic” phenomena, including the weather.

9. **The Black-Sholes Model. **They wanted to find a way to create investments with minimum risk. Fischer Black and Myron Scholes started working on the model which was then expanded by Robert Merton. The latter two won the 1997 Nobel Prize in Economics for the discovery. They set up an investment company, then went bust…

10. **Second Law of Thermodynamics**. It basically says that you cannot have your pie and eat it too when it comes to energy. In other words, there is a natural limit how efficient an engine can be, because of “entropy”, i.e. nature’s tendency to prefer disorder from order. Engine designers try to push efficiency to the limit.