DARK ENERGY DOESN'T EXIST?

New study shows the 'timescape' model of cosmic expansion, which doesn't have a need for dark energy because the differences in stretching light aren't the result of an accelerating universe, but instead a consequence of how we calibrate time and distance

- PROF DAVID WILTSHIRE

NE of the biggest mysteries in science dark energy doesn't actually exist, according to researchers looking to solve the riddle how the Universe is ending.

For the past 100 years, physicists have generally assumed the cosmos is growing uniformly in all directions. They employed the concept of dark energy as a placeholder to explain unknown physics they didn't understand, but the contentious theory has always had its problems.

Now a team of physicists and astronomers at the University of Canterbury in Christchurch, New Zealand, are challenging the status quo, using improved analysis of supernovae light curves to show that the Universe is expanding in a more complex, "lumpier" way.

Some new evidence supports the "timescape" model of cosmic expansion, which doesn't have a need for dark energy because the differences in stretching light aren't the result of an accelerating Universe, but instead a consequence of how we calibrate time and distance.

This takes into account that gravity slows time, so an ideal clock in empty space ticks faster than one inside a galaxy.

The model suggests that a clock in the Milky Way would tick about 35 percent slower than the same one at an average position in large cosmic voids, meaning billions more years would have passed in voids than would in turn allow more expansion of space, making it seem like the expansion is getting faster when such vast empty voids grow to dominate the Universe.