,.....brain....exploding....

Time may be running out

Time may literally be running out - and could one day vanish altogether, according to a bizarre new theory.

The suggestion has been put forward to explain a cosmological mystery that has baffled scientists.

A decade ago, measurements of the light from distant exploding stars showed the universe to be expanding at an accelerating rate.

Physicists assumed that a kind of anti-gravitational force must be driving the galaxies apart, and gave it the name "dark energy".

However, to this day no-one has been able to say what dark energy is or where it comes from.

The new theory from Professor Jose Senovilla, at the University of the Basque Country in Bilbao, Spain, offers a radical alternative idea.

He believes there is no such thing as dark energy. Instead, he says we have been fooled into thinking the expansion of the universe is accelerating because time itself is slowing down.

At our local everyday level, the change would be imperceptible. But it would be obvious from cosmic scale measurements tracking the course of the universe over billions of years.

Astronomers work out the speed of the universe's expansion from the frequency of light emitted by certain types of supernovae, or exploding stars. However, these measurements depend on our current perception of time, says Prof Senovilla.

If time has been slowing down, and clocks are now running more slowly than they did long ago, it would appear from our perspective as if things have been speeding up. Looking back over billions of years, galaxies would seem to be travelling away from each other faster and faster at various intervals since the Big Bang.