Tyler Johnson, MDiv
Tyler is a pastor and a former NASA engineer. He loves to explore truth through God’s word and God’s works. He lives in Iowa with his wife and four children and spends what little free-time he has pondering the mysteries of light
If you ever watched The Office you may remember the episode where Michael Scott blindly follows his GPS device’s directions and drives his vehicle right into a lake. There is probably a life lesson in that scene about being careful how blindly we follow anything, but that’s not the point I want to talk about this week. Instead I was reflecting on the early days of GPS technology and how things have advanced in the past couple decades. In the year 2000 GPS accuracy was somewhere in the range of 15 feet or so. Which was quite good for most applications. Today’s technology can pinpoint an object within a foot of its actual location. That’s pretty amazing. But it isn’t as amazing as the science that makes it work.
There are a lot of aspects that go into making GPS accurate, but one of the most fascinating elements involves Einstein’s theory of relativity. In the early 1900’s Albert Einstein found that space and time are flexible, not absolute. Time runs faster or slower, and space expands and contracts in certain circumstances. One of these circumstances is the presence of gravity. Gravity, technically speaking, isn’t a force, but is a warping of four-dimensional space-time. Gravity pulls us down towards the earth in the same way that a bunch of marbles on a trampoline would be ‘pulled’ toward you if you were standing in the center of it. Your mass would warp the plane of the trampoline and draw all the marbles towards you. This is what gravity does, but in four-dimensions.
The point is that clocks run slower in the presence of gravity than they do far from a gravitational field. (The movie Interstellar demonstrates this phenomenon well.) And this isn’t just a bunch of theoretical physics mumbo-jumbo, it actually has application in our daily lives. GPS technology has to account for relativistic effects to be as accurate as it is. The satellites that help pinpoint our locations on earth are far enough removed from the center of gravity of our planet that time runs a little faster for them, and space is expanded a bit. And these effects are enough to throw off location calculations.
On one hand, the science of relativity is simply amazing. When astronauts went to the moon they aged at a slightly different rate than the rest of us watching on earth. The duration of their trip would have been measured differently on the watches they wore as compared to the clocks at Mission Control in Houston. The differences would be related to the accelerations they experienced, their relation to the gravity of the earth and the moon, and even the speed they traveled. I find this absolutely amazing.
But here’s the other thing. Einstein’s theory of General Relativity isn’t just responsible for giving us accurate GPS technology, it is the main theory that physicists use to describe the history of our universe. Which means that the equation behind our accurate navigation also describes a universe with a 13.7 billion year history that slowly came to look like the stars, nebulae, and galaxies that we study today. In other words, the science that points us toward our destination also points toward a big bang.
Now, don’t get me wrong, there are still mysteries and challenges in the scientific reconstruction of our universe’s history. It is not the final word etched in stone. But I do want to take seriously the power of Einstein’s theory which, in over 100 years has only accumulated experimental support of its radical ideas. Mostly I want to ask the question, “If God can make a universe so wonderful and complex that time runs at different speeds, and space expands and contracts for different people in different places, is it really too much for us to imagine that God also created our universe billions of years ago?” I don’t think so. If we have eyes to see them, we may just find that there are even greater mysteries than these hidden in God’s creation.