New research suggests that the expansion of the universe may be caused by the deserts that make up the majority of the universe. Dark energy could be explained by the vast tracts of nothingness.

The largest pattern found in nature can be seen when you zoom out from the solar system. Astronomers can observe long, thin ropes of galaxies at these scales, where the whole universe appears as little dots of light. The largest can be more than 160 million light-years across and the smallest is 20 million light-years.

The gaps in a spider web are similar to the voids in the universe. The biggest thing in the universe is the Cosmic voids, which are the smallest things.

The power of nothing

Cosmic voids were first detected in the late 1970s, but have mostly been ignored. The brightly lit structures of the universe are the focus of astronomer and cosmologist. Dark energy was found in the 1990s.


The name dark energy is used to describe the expansion of the universe. Not only is the universe expanding every day, but it's also expanding fast.

The period of accelerated expansion is thought to have begun about 5 billion years ago. Dark energy is a cool name for a big problem.

The voids have something to do with dark energy. The effects of accelerated expansion are not felt inside of star systems or galaxies because of the strong attraction of matter. Our solar system isn't getting bigger because of dark energy. The effects of dark energy are more readily felt in the voids. It makes sense to look at the nature of the expansion.

A new research paper by a team of Iranian theoretical physicists takes this line of thinking to a whole new level. The paper was accepted for publication in the journal Monthly Notices of the Royal Astronomical Society: Letters and was published in July.

From the darkness

Is it possible that these huge regions of emptiness cause rapid expansion? The answer is not to only look at the existence of voids but also their dynamics.

Cosmic voids are much more than that. They grew from humble beginnings into their current enormous stature. Billions of years ago, the matter in the universe was spread out fairly evenly. Over time, any place that had more matter than average attracted more matter to it. The region had more attraction, which led to more growth. Matter accumulates over billions of years to form clusters.

As the structures grew, the voids became larger. We can see the growth of voids as putting pressure on the structures around them. As voids grow, the walls of the galaxies between them begin to thin out. All matter will be separated by hundreds of millions of light-years of emptiness when the voids end up dissolving the Cosmic web.

Space-time around the voids is distorted by the pressure. As the voids expand, they push on the galaxies at their borders, causing them to separate.

The authors found that the effects of all the large voids in the universe work together to cause an expansion. Current estimates of dark energy match the strength of this void-driven accelerated expansion.

Further studies are needed to test this idea. We need to get a better calculation of the combined pressure of the voids. We need to know if the strength of dark energy has changed over time. It is possible that dark energy isn't caused by exotic force or process in the universe but is a result of the evolution of emptiness.

It was originally published on Live Science