# Pi & Exponentials- The Unseen Forces that shape the Cosmos

**The structure of spiral galaxies:**Spiral galaxies are thought to be formed by the gravitational collapse of a rotating cloud of gas and dust. The shape of a spiral galaxy is determined by the balance between the centrifugal force of the rotation and the gravitational force of the mass of the galaxy. This balance is described by a mathematical equation that includes pi.**The formation of black holes:**Black holes are formed when a star collapses under its own gravity. The radius of a black hole is determined by its mass, and this radius is related to pi.**The evolution of the universe:**The universe is thought to have been created in a hot, dense state about 13.8 billion years ago. Since then, the universe has been expanding and cooling. The rate of expansion of the universe is determined by the amount of matter and energy in the universe, and this rate is related to pi.**The search for extraterrestrial life:**Astronomers are searching for extraterrestrial life by looking for planets that are similar to Earth in terms of their size, temperature, and atmosphere. The probability of finding a planet that is habitable for life is related to pi.**The orbits of binary stars:**Binary stars are two stars that are gravitationally bound to each other. The orbits of binary stars are elliptical, and the shape of the ellipse is determined by the masses of the stars and the distance between them. This shape is described by a mathematical equation that includes pi.**The formation of planetary rings:**Planetary rings are thought to be formed by the collision of comets or asteroids with a planet. The size and shape of planetary rings are determined by the properties of the material that makes up the rings, as well as the gravitational forces of the planet and the Sun. These properties and forces are related to pi.**The structure of neutron stars:**Neutron stars are the collapsed cores of stars that have exploded as supernovae. The radius of a neutron star is about 10 kilometers, and its mass is about the same as the mass of the Sun. This extreme density is due to the strong force, which is a force that binds neutrons together. The strong force is related to pi.**The evolution of black holes:**Black holes can evolve in a variety of ways, depending on their mass and the environment in which they are located. For example, black holes can merge with other black holes, or they can accrete matter from their surroundings. The evolution of black holes is described by mathematical equations that include pi.