Warping the Universe

But what are gravitational waves, and why couldn’t anyone measure them until now? The answers involve the nature of gravity. So what is gravity? Isaac Newton says, “Gravity is a force of attraction between any two objects.” This sounds mysterious. Why would two objects attract each other? Albert Einstein says, “Because they warp the fabric of space, so that moving objects curve toward each other.” Back when Einstein proposed this, scientists wanted to see evidence before they believed it. But the evidence quickly started to mount, and today this theory has passed every test we’ve managed to give it. However, ...

Living as a Christian in a Secular Grad School (Part 2)

by Maxwell Lorentz Becoming a scientist involves more than just the normal four years of college—you also need four to eight years of grad school to earn your Ph.D. This graduate school is almost always secular, so in my last post I started sharing four pieces of advice for anyone who is trying to be a faithful Christian in such a place. (And a lot of this advice applies to life in general, not just Christians in grad school.) The first two pieces of advice, from last time, were . . . Your life is even more important than your ...

Living as a Christian in a Secular Grad School (Part 1)

by Maxwell Lorentz Do you want to become a scientist? I hope many of you do. The world badly needs top-notch scientists who study science because they love God, and who love God more than anything else. To become a scientist, you need years of college. You start by getting a standard four-year degree (typically called an undergraduate degree). With this degree, you’ll probably have enough knowledge about the subject to get a job applying it. But to become an actual scientist—someone who discovers the science instead of just using it—you’ll need several more years of study (called graduate school, ...

Supermassive Black Holes: Monsters in the Dark

by Maxwell Lorentz Over 2 billion light years away, there lies a galaxy named Hercules A. At its heart lurks a supermassive black hole, and it is a monster—billions of times more massive than the sun, and a hundred billion times brighter than the sun—one of the most powerful objects in the Universe. Supermassive black holes are always massive (by definition), but they’re not always as bright as the one in Hercules A. Often they are quite dark, lurking silently in space. In fact, astronomers think that most galaxies—and maybe even all galaxies—harbor one of these monsters at the center. ...

How to Make a Black Hole

A black hole is a place in space where the gravity is so strong that not even light can escape. But how can black holes form? What would make gravity so strong? To answer this question, we need to think about how gravity works. Gravity depends on two things—mass and distance. If you make something more massive, its gravity will get stronger. Or, if you get closer to something, its gravity will get stronger—in particular, if you cut the distance in half, the object’s pull will be four times as strong.[1] There is a catch, though. When we say “distance,” ...

Black Holes: Waterfalls in Space

by Maxwell Lorentz “What goes up must come down,” they say. But is this true? Throw a ball, straight up, as hard as you can. It goes up—and then comes down. If you could throw it 1,000 miles per hour, it would go more than 6 miles high—and then come down. If you could throw it 10,000 mph, it would go twice as high as the Hubble Space Telescope—and then fall back. But if you could throw the ball 26,000 mph, it would keep going and never return—because this speed is faster than Earth’s escape velocity.[1] The Earth’s escape velocity ...