A Brief History of Equations

This article provides a brief history of several equations and theories thought history. It will provide an idea of what each equation is for and will describe the important events in each of their history. This is not an in depth article. It is only to provide a brief explanation of each equation or theory.

Newton's Law of Gravitation

This equation was first seen in Philosophiae Naturalis Principia Mathematica which came out July 1687. Newton created this equation in Lincolnshire County, modern-day England. Its purpose is to show the idea that all particles of matter in the universe attract each other through gravity. This equation shows how strong that attraction is. The story goes that Isaac Newton saw an apple fall and wondered why fruit always fell straight to the earth. According to his own motion laws, anything starting to move from standing position is undergoing acceleration. When there is acceleration there is a force, the apple started in the tree and ended up on the earth. Meaning that there must be a force of attraction between the apple and the earth. It there is an attraction at that elevation there should be an attraction at higher elevations. Which raised the question; Why doesn't the moon come crashing into the earth? Imagine if there is a cannonball that was shot. It has enough force to continue moving straight. The earth pulls the cannonball toward the earth but it has enough force to continue moving around the earth. It there was no gravity the cannonball would continue flying straight away from the earth. If there is a balance between the force put on it to set it into motion and gravity, an orbit is caused.

Newton's Second Law

This equation was created in 1716. Newton is given most of the credit for the equation F=ma. Although Galileo Galilei did all the testing at the Leaning Tower of Pisa. Galileo also established that gravity produces acceleration. Newton used Galileo's findings to prove F=ma. The purpose of this equation is to show that the force put on an object is the mass of the object times the acceleration.

E=mc²

This equation was created by Albert Einstein in 1905. It was published in a 3-page article in a scientific journal in Bern. It was titled; "Does the Inertia of a Body Depend on its energy content? The purpose of this equation is to show that the Energy in an object is its mass times the speed of light squared. Einstein liked to ponder riddles and one such riddle was; If a person was flying in space at the speed of light with a mirror in his or her hand, what would they see? From there he assumed that the speed of light was a constant. He returned to the mathematical electromagnetic equations that were worked out years previously and plugged in the speed of light for C(a constant). Out came the equation E=mc². If the speed of light is a constant then energy is interchangeable with matter and mass. The purest form of energy is electromagnetic radiation moving at a set speed. If matter or mass goes at that speed(mass multiplied by the speed of light)it becomes energy and if energy moves at a slower speed it becomes matter. Twenty years after the equation was formulated the technology to test it was created and it was proven true.

π=c/d

The purpose of this equation is to show the ratio of the circumference of a circle divided by its diameter. In 1900BC the Babylonians estimated pi to be about 3.125. In the same century, the Egyptians estimated pi to be 256/81 which is about 3.16. In 250BC Archimedes of Syracuse used 96 sided Archimedes polygons to estimate pi to be between 3.1408-3.14285. Later in 460AD, Zu Chongzhi used the same method as Archimedes but instead of 96 sided polygons, he used 12,288 sided polygons to estimate π to 355/113. In 1400AD Madhava of Sangamagrama used the Madhava-Leibniz series to accurately estimate pi to 11 decimal places. 307 years later in 1707AD William Jones was the first to use the Greek letter π to represent pi. The longest accurate calculation of π before the advent of the computer was done by D.F. Ferguson who calculated pi to 620 digits.

Euler Characteristic

The Euler Characteristic states that V-E+F=2. Its purpose is to show that the vertices of a 3D figure minus its edges plus its faces always equals 2 as long as the shape isn't inverted. Leonhard Euler created this equation in 1751. He made this observation while he was observing different shapes and 3-dimensional figures.

Minimal Surface

Leonhard Euler and Joseph-Louis Lagrange created this equation in Switzerland and in Italy during the year 1768. Its purpose is to find the surface of least area stretched across a given closed contour. For example a bubble on a bubble wand.

General Relativity

This theory was created by Albert Einstein in 1915 in the city of Berlin. Its purpose is to show that massive objects cause a distortion in space-time, which is felt as gravity. This distortion can cause gravitational lensing, gravitational redshift, and gravitational waves. In 1905 Einstein determined that the laws of physics are the same for all non-accelerating observers and that the spread of light in a vacuum was independent of the motion of all observers. He called this the theory of Special relativity. Einstein spent 10 years trying to include acceleration in his theory and published it in 1915 as the theory of General Relativity.

References

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📰 Article(s) of the same category(ies)

• Proving Einstein Right
• Great Unification Event (physics)
• Laws of attraction
• Academic genealogy of theoretical physicists

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