This is surely going to be a real bummer not only for the physicists who have devoted a substantial part of their career studying dark energy, but our current understanding of physics and the Universe could also be at stake. Although, that’s something we all will have to deal with if the recent findings from a simulation of the cosmos are found to be consistent in subsequent studies. That’s because, among a slew of other important observations, said simulation also shows that the elusive dark energy that is believed to comprise 68% of the Universe may not exist at all.
It’s as if 68% of the Universe has vanished all of a sudden — just like that!
A backdrop for the uninitiated — Ever since the late 1990s, scientists have been by and large certain that the Universe is not just expanding, but it is expanding at an ever increasing speed. That proposition was diametrically opposite to the previously widely-accepted model of the cosmos that showed the expansion of the Universe slowing down due to the cumulative effect of gravitational pull between all the objects and gasses in the Universe.
That remodeling eventually led physicists to conclude that mysterious form of energy, aptly called dark energy, was behind the accelerated expansion of the Universe. However, according to a new study that included the aforementioned simulation, dark energy is probably just an illusion caused by the changing structure of the cosmos.
Originally published in Monthly Notices of the Royal Astronomical Society, the researchers argued that the current models of the Universe are failing to aptly explain its changing structure. Rather, the study says, these conventional models depend on approximations in addition to assuming that matter comes with a uniform density.
“Einstein’s equations of general relativity that describe the expansion of the universe are so complex mathematically, that for a hundred years no solutions accounting for the effect of cosmic structures have been found,’ said the study’s co-author Dr László Dobos of Eötvös Loránd University, the Daily Mail reports.
‘We know from very precise supernova observations that the universe is accelerating, but at the same time we rely on coarse approximations to Einstein’s equations which may introduce serious side-effects, such as the need for dark energy, in the models designed to fit the observational data.’
The new Avera model
In addition to raising questions about the existence of dark energy, the physicists also proposed a new model of the cosmos. Dubbed the Avera model, it takes into account the early clumping of matter that essentially led to the formation of very large scale structures.
Unlike all the conventional simulations that show a homogeneously expanding Universe, the Avera model shows that different regions of the cosmos can expand at different rates.
The researchers clarified that they are not disputing the accelerated expansion of the Universe. Instead, the model shows that any such expansion does not necessarily require dark energy as a mandatory ingredient.
“We do not question its validity; we question the validity of the approximate solutions,” said Dr. Dobos.
“Our findings rely on a mathematical conjecture which permits the differential expansion of space, consistent with general relativity, and they show how the formation of complex structures of matter affects the expansion.”