Title: Relativity versus quantum mechanics: the battle for the universe | Physics | The Guardian
Headings: Relativity versus quantum mechanics: the battle for the universe
Relativity versus quantum mechanics: the battle for the universe
Small is beautiful
Chunky space does not neatly align with the ideas in string theory – or in any other proposed physics model
A bigger vision
And the winner is?

Content: What emerges from the dust-up could be nothing less than a third revolution in modern physics, with staggering implications. It could tell us where the laws of nature came from, and whether the cosmos is built on uncertainty or whether it is fundamentally deterministic, with every event linked definitively to a cause. Small is beautiful
Hogan, champion of the quantum view, is what you might call a lamp-post physicist: rather than groping about in the dark, he prefers to focus his efforts where the light is bright, because that’s where you are most likely to be able to see something interesting. That’s the guiding principle behind his current research. The clash between relativity and quantum mechanics happens when you try to analyse what gravity is doing over extremely short distances, he notes, so he has decided to get a really good look at what is happening right there. “ I’m betting there’s an experiment we can do that might be able to see something about what’s going on, about that interface that we still don’t understand,” he says. A basic assumption in Einstein’s physics – an assumption going all the way back to Aristotle, really – is that space is continuous and infinitely divisible, so that any distance could be chopped up into even smaller distances. But Hogan questions whether that is really true. Just as a pixel is the smallest unit of an image on your screen and a photon is the smallest unit of light, he argues, so there might be an unbreakable smallest unit of distance: