After slightly missing the deadline for this blog, I’ve decided to say “I’m not late, it’s all relative”.
Many of you may be also hoping for more time to prepare for your interviews/exams, unfortunately you’re clutching at straws if you think this entry will actually teach you how to slow time down (although I’ve seen next August’s entry and that contains blueprints for a DeLorean).
Right, before we approach slowing time we have to consider what time is. Simply put, it’s the thing that separates events. In most people’s life, that’s all that is required, but interesting things start to happen when you start to pick up some speed.
Let us consider two spaceships, SS Einstein and SS Galileo. Einstein is travelling at 10000m/s and Galileo is stationary. If we stood on Einstein and looked at Galileo, it was seem that Galileo is moving at 10000m/s. This is relative motion.
So, what if we fire a beam of light from Einstein, that beam should be travelling away from us at c-10000 right? Oddly no …. It’s still c. If we travelling at (c-2) m/s and fired a beam, it would still travel away from us at c. We can only conclude that the speed of light is not relative.
Here is the birth of special relativity. It is no longer true that all frames of reference travelling at constant speed are equivalent, only those that are travelling below the speed of light. Once the speed of light is reached, the equivalence breaks down.
If the motion of light is not relative, then this mean other quantities we consider absolute to actually be relative. Things light distance, mass, and even time.
Leading on from this, a little thought experiment for you to try. Imagine two different events happening. Now do these events happen at the same time, or at the same place? If we can observe one, and then get to the next one to observe that, then we can say that they happened at different times.
If no material object or a beam of light can reach the second event then we can say they happen at the same time … but light takes time to travel so we can say that these events happen at different times at different locations.
So if we have three events, A, B, and C. If A is a friend texting us that they are outside, and then we open the door the second they get out of their car, B, we can say that A happens before B. If C however is an event that happens in another galaxy, no observer can get there within thousands of years, so technically the event C can happen 1000 years after A but still can be considered instantaneous with A.
This lead to the idea that we shouldn’t consider time and space (distance) as separate entities but combine them into 4 dimensional space-time.
So, how do we slow time? Special relativity causes something called “time dilation”, simply put “the faster you go, the slower time goes relative to someone travelling slower”.
There is no physical boundaries to any speed below c, and if travel at 99.9% the speed of light, time would be 22 times slower relative to Earth. Although this sounds bizarre, it’s actually been proven. Fly on a commercial jet and you’ll gain 0.0000003s!