Imaginary Unit (i)

The imaginary unit, i, is a solution to the quadratic equation x^2 + 1 = 0, where (-1)^2 = 1 or x=√-1. It is called imaginary because there is no real number with this property. Imaginary numbers helped extend the real number system to the complex number system, in which at least one root for every nonconstant polynomial exists.

Boltzmann’s Constant

The fundamental constant of physics, the Boltzmann constant, is one of the seven "defining constants" that have been given exact definitions.

The Speed of Light

The speed of light is a universal physical constant. It is equal to 299792458 meters per second (approximately 300000 km/s).

The Avogadro constant is a number used to explain atoms, molecules, ions, and electrons. It is named after the scientist Amedeo Avogadro.

Planck’s Constant

Planck's constant is a fundamental physical constant that is utterly important in quantum mechanics. It is named after Max Planck.

The Golden Ratio (Phi)

In math, two quantities are in the golden ratio if their ratio is the same as the ratio of their sum to the larger of the two quantities.

Euler’s Number (e)

Euler's number, the number e, is a mathematical constant approximately equal to 2.71828. You see the number e in mathematics almost every day.

Euler’s Identity

Euler's identity is a mathematical beauty that ties five fundamental mathematical constants in mathematics together.