The Theory of Relativity

Theory of relativity

The theory of relativity was conceived by Albert Einstein. His theory took the already complex world of Quantum Physics and added another level. Quantum Physics as a whole is the study of subatomic particles, Einstein focused in on a small part of such of a vast concept breaking his contributions to Relativity into two different theories.

In 1905 Einstein published his first article on Special Relativity, the first work of his many publications on what became known as the theory of relativity. In this article, Einstein relays how to interpret motion between different inertial frames (or the relativity of places moving at a constant speed to each other). With special relativity, Einstein focused only on special cases of motion - hence the name- his theory only applying when both objects are in motion in uniform. With experiments that proved both theory's wrong, Einstein created a new theory using two important physics laws as his guide.

Physics Law Number One: The Principle Of Relativity: The laws of Physics don’t change even when objects move in an inertial frame of reference. This theory got its kick start during the time of Aristotle when the Greek philosopher said that heavy objects faster than light objects. Then Galileo discovered that, in fact, Aristotle was wrong, objects move with the same acceleration depending on their velocity.Using these principles Newtonian mechanics added on other concepts, the law of motion, gravitation, the law of an absolute time. Then two scientists, Joseph Larmor and Hendrik Lorentz, discovered that Maxwell's equation was correct and Einstein used this discovery to construct Special Relativity.

Maxwell’s Equation: how electric and magnetic charges are generated and altered by each other's charges and currents. This theory was created mathematician James Clerk Maxwell. Hi equations, mixed with the Lorentz force, began the foundations for classical electrodynamics, classical optics, and electric circuits.

Physics Law Number Two: The Principle Of The Speed Of Light: This law is pretty simplistic, the speed of light is the same to all observers no matter what the observers relative motion is. Seems pretty easy, no matter if you are on a boat and your friend is on Jupiter, the speed of light will remain the same. So Einstein took this law, looked at it for a little bit, and then he said, “You know what, I’m gonna make this fit into my whole Special Relativity thing,” [not a direct quote] and then he did it. According to Einstein's theory of Special Relativity light in a vacuum (a special case) moves at 299,792,458 m/s, and also, no one can go as fast as the speed of light.


Now, Einstein's Special Relativity provided the data for one of his biggest theories, time space. Up until Einstein's thought experiment about time and space being one connected unit, scientists had just assumed that the two were very separate entities. It's easy to think that time and space, neither of which seem to be similar, are dependent on each other, let alone connected to each other. However, Einstein had this big idea that maybe the two were very much connected, time and space weaved together. To understand space-time, think of this thought experiment: you are in a spaceship and you are shooting a laser beam at the mirror in front of you, to you the laser is moving at the speed of light. Now if another spaceship comes by carrying Alice she will see the laser two, but her laser will be moving at what looks like a different speed because she herself is moving at a different speed. However, if you take the measurements the laser is moving at the same speed.

Einstein's theory of general relativity was published in 1915. The theory itself focuses on geometric gravitation. With his earlier theory of Special Relativity uniting space and time into one entity called space-time, Einstein applied general relativity to theorize that gravity was bending space-time. To do so Einstein constructed a set of field theories, including one that defined the way that gravity responds to matter in space-time.

In the wake of his research on general relativity, Einstein introduced another principle into his work, the principle of covariance. The principle of covariance states that the laws of physics have to stay the same in all coordinate systems. Imagine a spaceship moving at a constant speed. The principle of covariance states that the space-time coordinates of gravity have to be the same as the space-time coordinates of the spaceship.

Alright, let's talk about geometric space-time and how it works. If you took everything out of space-time it would theoretically be completely flat. Now, using the principle of covariance, when objects are put into space-time curves around it. Let’s go back to the spaceship. If you are in a spaceship in empty space then from inside the spaceship space-time would appear to be curving around you. The same happens with planets and stars, the sun is obviously the biggest star near earth so in the orbit of the planets around the sun, the sun is the main center for space-time curvature and the planets follow the path made from its curve.



Now that we have covered the basics of the theory of relativity, how about we focus on a brief summary of Einstein as a person - well, at least as a respected scientist. Einstein was born in Ulm, Germany on March 14, 1879, his family was Jewish and he had a tutor from Poland. The tutor was a med student and liked to tell Einstein and his siblings about science and Einstein took a big liking to the subject, so much so that when he was in his teens he wrote his first essay on the topic called, "The Investigation of the State of Aether in Magnetic Fields." Since Einstein clearly loved science, he continued it as a profession. His career really took off with his idea of tiny particles having a whole lot of energy (E=mc2) and later the theory of relativity. In 1921 Einstein won the noble prize, then he was inducted into the "Pour le mérite", then he fled from the Nazis, then he was honored by a whole ton of science communities. On April 18, 1955, in Princeton, New Jersey, Einstein died, but he will always be remembered as one of the most influential men in science.

How Einstein left his desk on the day he died. 

It becomes very present towards the end that the theory of relativity is different than Newtonian gravitation. Newton found gravity, at least, he found a tug that objects exert on to each other, the bigger the object the harder the tug, and Newton's equations still remains used today. In fact, most every human observation from earth can be calculated precisely through Newton's equations. There was a flaw in Newtons plan though, see, Newton's gravity didn’t have a visual form, he left that open for people’s own interpretation. That was what Einstein started with. See Einstein had this dream about gravity, except it wasn’t gravity, it was space-time and it’s geometric curves that form through the principle of covariance in general relativity. Einstein's theory of relativity disputes how Newton's entire theory works, but, nevertheless, Newton's equations stay steady.