How Astronomy Has Opened the Gates to Humanity’s Greatest Inventions | Alex Filippenko| Big Think

One can wonder why does astronomy, or any sort of abstract pure research for that matter, make any difference to us, to the typical person in the world. Well, first of all, thinking about the universe and figuring out how things work is something that, of all animals, only humans can do. Only we have the intellect, the curiosity, the opposable thumb with which to build machines to explore nature. So, some of us should do it.

Second of all, these kinds of discoveries, discoveries about the cosmos, excite kids. You know, I like to say that astronomy is the gateway science. It gets kids interested in science and technology because they hear about all these amazing discoveries. I myself, as a kid, was thrilled by the lunar landings of the Apollo mission. Now, most kids won't go on into astrophysics, but what they'll do is they'll study science and technology, and they'll go into fields that are more immediately useful to society, such as applied physics, engineering, and computer science, and medical physics. But you know, the bug that bites them is open astronomy.

Finally, you never know what practical spin-offs there might be, and let me give you a few examples. A century ago, when quantum physicists such as Einstein, Bohr, Heisenberg, and Schrödinger were developing quantum physics, they had not the slightest practical application in mind. They didn't want to make a better toaster or a better bicycle or whatever. They wanted to understand the nature of light and why atoms exist, why atoms are stable, and other such questions of that sort that seemed incredibly far removed from our everyday lives.

Well, fast forward a century; you could not imagine today's high-tech world without an understanding of the micro physics, the quantum world. Look at the silicon revolution, for example. Look at lasers. Look at nearly everything—it all stems from quantum physics. Who would have thought that a century ago?

Another, even perhaps more abstract idea, is Einstein's general theory of relativity. The theory that the presence of mass or energy curves or warps the shape of space and of time around it. So, for example, our Sun forms the dimple in space, and Earth moves along its natural path through that dimple. So too, Earth forms a dimple, and the moon moves along its natural path through that warped space. That's what gravity is.

Newton had a formula for gravitational attraction, but he didn't know what it was, and Einstein came up with a theory. Well, you might say, "Who cares? As long as gravity works, you know, what do we care what the exact mechanism is?" Well, it turns out that Einstein's theory makes predictions that are, in subtle ways, different from Newton's predictions.

And for things like the Global Positioning System (GPS), you have to take the effects of general relativity into account. The clocks in the satellites up in space—these satellites communicate with your device in your car—they run at a slightly faster speed than the clocks here on Earth. If that difference in the rate of passage of time had not been taken into account by the physicists and engineers who designed and built the GPS system, GPS wouldn't work.

So here's something of incredible military and commercial value that simply would not work if we didn't understand gravity in a fundamental way according to Einstein, this idea of curved space-time. So again, who would have thought that a century ago, when Einstein was developing the general theory of relativity, that it would have this incredible practical application?

Sure, we might never get close to a black hole, which is an extreme prediction of general relativity, but it doesn't matter. The theory was developed; it's beautiful, it excites kids, and it even has practical applications. So with much of astronomy, we don't know what the spin-offs will be, but we do know that as humans, we can accomplish these goals and can also excite kids into pursuing areas of science and technology, and that, in my opinion, is really good.