The universe may be dominated by particles that break causality and move faster than light, new paper suggests

In a new paper that has yet to be peer-reviewed, the physicists propose that our universe is dominated by tachyons — a hypothetical kind of particle that always moves faster than light.

Tachyons almost certainly don't exist; going faster than light violates everything we know about the causal flow of time from past to future.

But the hypothetical particles are still interesting to physicists because of the small chance that even our most closely held notions, like causality, might be wrong.

The researchers calculate that an expanding universe filled with tachyons can initially slow down in its expansion before reaccelerating.

(Image credit: NASA Goddard)The physicists found that a tachyon cosmological model was just as good at explaining the supernova data as the standard cosmological model involving dark matter and dark energy.

We now have access to a wealth of data about the large-scale universe, like the cosmic microwave background (remnant radiation released just after the Big Bang) and the arrangement of galaxies at the very largest scales.