For fifty-two years, a claim by Stephen Hawking lived on as a theory no one could prove directly: that black holes, contrary to everything we knew about them, slowly evaporate. Now a group of physicists in Germany says it has seen, for the first time, exactly how that happens - and not in space, but in a laboratory.

The team led by Lorenzo Procopio at the University of Paderborn did not create a real black hole - that is impossible on Earth. Instead, using an ultrafast laser pulse through a special optical fibre, they made something that behaves like a black hole: one pulse alters the properties of the fibre and creates an analogue of the so-called event horizon for a second beam of light. With that trick, black-hole physics unfolds before the scientists' eyes, without needing a real hole light-years away.

What they saw confirms the biggest question: Hawking radiation, the mechanism by which black holes lose mass and eventually - after an unimaginably long time - disappear. "Our experiment and theory show that Hawking radiation is the result of a direct process," the researchers announced, adding that real black holes in space probably radiate in an equally simple way.

Why should anyone in Skopje, Bitola or Tetovo care about a black hole evaporating? Because this is one of those rare pieces of news that isn't about money, war or power - but about the frontier of human knowledge. A person who, with a laser in a room at a German university, tests an idea conceived half a century ago and discovers that the universe works more simply than we thought. In a world full of claims that fall apart under scrutiny, it is good to be reminded now and then that some people still measure, check and answer questions that will outlive them.