“
Imagination is more important than Knowledge.” Albert Einstein.
Have you ever wondered what the General Theory of Relativity is? In this blog, I'm going to put all this prolixity in my own words. Essentially, it is a theory about gravity. For a long time (and thanks to Newton), people thought of gravity as a force. We toss up a ball, it reaches an apex, and then it seems like some force pulls it back down to us. A force made the apple hit Newton on the head. A force keeps us on the ground so we don’t float out into space.
Think of the orbit of the moon around the world, or any moon, or any orbit for that matter. Suppose you tied a 5-foot rope to a ball and then set the ball down beside you: there the ball would sit, with the rope dangling from your hand, and yet (remember) connected to the ball. Suppose further that you pick the ball up using the rope and start to rotate faster and faster. The ball would begin to ‘orbit’ around you. In this analogy, gravity is the rope. Newton would say: the earth’s gravity is greater than the moon’s, and that’s why the moon orbits the earth - in the spirit of Jimmy Stewart in It's a Wonderful Life, the Earth through a lasso around the moon!
Or, do you remember the ride at the Roller-Coaster Theme Park that spun around at a high speed? We would press our backs up against a mat around the perimeter of the ride, and as the the ride would spin faster and faster we would feel more and more pressure up against the wall. Newton would also like this analogy. That’s why everything on Earth stays on the ground: the Earth is spinning very fast. Airplanes actually ride gravity like a surfer catches a wave: they don’t actually defy gravity, but use it, harness it, to become airborne.
Enter Albert Einstein. Einstein changed everything. For instance, up until Newton, everyone thought of Space and Time as two distinct realities. Space was understood using the metaphor of a spatial container (Newton) or particular points on a graph (Leibniz). Time was understood using the metaphor of already existing dominos, and time’s ‘flow‘ was understood using the metaphor of the point during which the domino falls and hits the one in front of it.
But not Einstein. According to him, there aren’t anymore two distinct realities: Space and Time - there is just one: space/time. And space/time should be understood using the metaphor of a fabric, with space and time interwoven together. Think of a trampoline. If you stand in the center, there’s a big hollow there. Now, think of our solar system. The sun is in the center of a huge, space/time fabric that is like the fabric of a trampoline, making a huge hollow. The reason why the planets revolve around the sun is because they’re making revolutions along the space/time fabric ‘because of’ the hollow.
Every single object - ants, trees, you, me, cell phones, Obama, mites, spiders - make tiny hollows or dents in the fabric of space/time! Everything stays on the Earth because the Earth makes the biggest dent in space/time compared to anything else on Earth, and the dent is big enough to do this.
Lets go little further in understanding something else. If the metaphor of a fabric is accurate (and it probably is - it’s had a near perfect history of predictive value), something else is possible: wormholes. If Einstein’s theory is right, there are dents in this fabric everywhere; but what if a part of the fabric at one end ‘folds over’ and meets the ‘underside’ of another part of the same fabric? And what if at that point of mutual contact, we could travel - instantaneously - to another part of space/time literally billions of light years away? There would be paradoxes, and I’ll get into those in more depth later. But quickly: the moment you arrived there - according to the theory - everyone you knew would have been dead for a while. And yet: if you went back through a second later, you would have aged a second, and perhaps everyone else would have aged 50 years. So, what to you took a second, took for them 50 years. But this gets into the Special Theory of Relativity, which is a little harder to understand, but I’ll get to it in the next blog!
