Steve Connor: Lack of waves causes ripples of excitement

Sometimes in science, no news is good news, and a "non-discovery" is actually a result. This apparent contradiction was exemplified last week with the latest non-findings from an experiment to detect the elusive gravitational waves predicted by Albert Einstein, right, a century ago when he formulated his general theory of relativity.

Gravitational waves are ripples in the fabric of space-time, the material that Einstein envisaged to link... er... space and time. Anyway, they are sometimes called gravity waves, which somehow makes them easier to understand.

The point is, like so much of what Einstein predicted, no one has actually found one, which is why some pretty complex machines have been set up to try to prove they really do exist. One of these is the LIGO, or Laser Interferometer-Gravitational-wave Observatory, based in Washington state and Louisiana.

Laser beams are bounced off heavy mirrors kept miles apart in the hope of detecting any slight disturbances caused as a gravity wave passes through. Big waves, caused by the collision of two black holes in space, for instance, should cause a recognisable spike, whereas the smaller "stochastic" gravitational waves in the background, caused by events at the Big Bang 13.7 billion years ago, would amount to a tiny flutter of the laser beams.

Anyway, the point is that these smaller background waves have not been detected by LIGO in the measurement range it has been looking at. Bingo, a result. It means that the scientists can stop looking there, and start looking somewhere else.

The scientists involved are reported to be excited about their non-discovery. Just wait until they find the real thing.

Hooray for WHO ruling

Talking of non-events, it has come to my attention that the World Health Organisation has made a ruling on homeopathy. It does not recommend it for treating HIV, TB, malaria, influenza or infant diarrhoea. Mmm.

It would, of course, be more surprising if the WHO said it has decided to recommend homeopathy, but given that it is supposed to be an evidence-based medical authority, that was hardly likely.

However, at least it is now clear to the young doctors and health workers in Africa and other parts of the world where these diseases are real killers that homeopathy should have no place in their treatment, a clarification that many of these dedicated people have welcomed.

A winning formula

More schoolchildren are now taking physics and maths A-levels compared to recent years. That can only be good news for Britain, providing they don't end up using their skills in banking and finance, like many of their predecessors.