Relatively Easy. Relatively Difficult. It’s A Matter Of Perspective.
Just for fun a few days ago or so (plus a few more) I decided to take a shallow dive into the Theory of Relativity. It’s something I’d heard of before and ran across while looking into another subject. I’d never studied it and didn’t actually know what it was other than something associated with Albert Einstein.
What did I find out from a few internet resources (also plus a few more now…)?
For a beginner’s first effort at taking it on I will say that it’s actually incredibly interesting. I started first with it’s history and learned it had a world changing effect. Einstein released his first publication in 1905. Almost overnight he rose from obscurity as a Swiss patent clerk to a global figure. This is where my shallow dive started to go deeper. It’s hard to stop at just learning about Einstein, because to understand how radical his idea was and why it spread so quickly throughout the scientific community it helps to know something about the work of Isaac Newton. Once you begin to do that, it helps to understand what a great thinker Newton was by looking at the great thinkers before him whose ideas he upended.
Quite the hole to get pulled down into and I’m actually no where close to being done.
The Theory of Relativity itself appears to be based on a fairly simple concept which is set out in the example below. There are many sources that delve into the topic and explain it in a much more complex fashion. For me they were too complex as a starting point and that’s why I began with this simpler and easier to understand version:
“One example of relativity is to imagine two people on a train playing ping-pong. The train is traveling at around 30 m/s north. When the ball is hit back and forth between the two players, the ball appears to the players to move north at a speed of around 2 m/s and then south at the speed of 2 m/s.
Now imagine someone standing beside the railroad tracks watching the ping-pong game. When the ball is traveling north it will appear to travel at 32 m/s (30 m/s plus 2 m/s). When the ball is hit in the other direction, it still appears to travel north, but at a speed of 28 m/s (30 m/s minus the 2 m/s). To the observer by the side of the train, the ball always appears to be traveling north.
The result is that the speed of the ball depends on the ‘relative’ position of the observer. It will be different for the people on the train than for the person on the side of the railroad tracks.”
https://www.ducksters.com/science/physics/theory_of_relativity.php
This scenario is an example of Einstein’s first theory of relativity: special relativity. This says essentially that “[t]he laws of physics are the same in all inertial frames, and the speed of light is the same for all observers. Whether you’re in a broken-down school bus, a speeding train or some manner of futuristic rocket ship, light moves at the same speed, and the laws of physics remain constant. Assuming speed and direction are constant and there wasn’t a window to peer through, you wouldn’t be able to tell which of these three vessels you were traveling in.” Source: How Stuff Works
In other words, distance and time aren’t absolute. Each can appear differently to different people depending on their positions relative to one another.
To be continued.
Easter Egg #1: Einstein Documentary and the Theory of Relativity
