Gravity

Category archives for Gravity

There’s something puzzling about black holes, if you stop to consider it. On the one hand, they’re objects so massive and dense — compacted into such a small region of space — that nothing can escape from it, not even light. That’s the definition of a black hole, and why “black” is in the name.…

If we want to understand the Universe at a fundamental level — all the forces on all scales — the biggest obstacle facing us is to come up with a correct, consistent, testable and verifiable theory of quantum gravity. To no one’s great surprise, we’re not quite there yet. In 2001, Lee Smolin — one…

“I just think too many nice things have happened in string theory for it to be all wrong. Humans do not understand it very well, but I just don’t believe there is a big cosmic conspiracy that created this incredible thing that has nothing to do with the real world.” –Edward Witten It’s a difficult…

Pluto’s Unique Moons! (Synopsis)

“Movin’ right along. You take it, you know best. Hey, I’ve never seen the Sun come up in the West?” –The Muppet Movie Few things in this world are as regular as sunrise and sunset. With the application of a little physics, you can predict exactly where and when the sun will rise or set from…

“Oh leave the Wise our measures to collate. One thing at least is certain, light has weight. One thing is certain and the rest debate. Light rays, when near the Sun, do not go straight.” –Arthur Eddington While we know full well today that Newtonian gravity is just an approximation to a more correct theory…

“[I]f there were no light in the universe and therefore no creatures with eyes, we should never know it was dark. Dark would be without meaning.” –C.S. Lewis The Universe had two periods where light was abundant, separated by the cosmic dark ages. The first came at the moment of the hot Big Bang, as…

“Journalists often ask me when I go to the field, ‘What do you expect to find?’ And my answer always is, ‘The unexpected,’ because we’re just looking at the tip of the iceberg; we’ve just scratched the surface.” –Donald Johanson Imagine you wanted to know what your acceleration was anywhere on Earth; imagine that simply…

The Missing Piece (Synopsis)

If you’re not a theoretical physicist yourself, you might think that physics is physics — we ask questions about the Universe, do experiments/make observations, and get the answers — and math is just a tool that we use to help us get there. But that really sells the power of mathematics short. For a physical…

“We live in a world that has narrowed into a neighborhood before it has broadened into a brotherhood.” –Lyndon B. Johnson When you think of our own cosmic backyard — our planets, Sun, the nearby stars, and even the closest galaxies to us — you probably don’t think of them in the context of the…

“Hope is not the conviction that something will turn out well but the certainty that something makes sense, regardless of how it turns out.” –Vaclav Havel When you take a look at the planets in our Solar System, one of the most striking features about them is that they all orbit in almost exactly the…