At this point of the game, everyone takes for granted that, at the beginning, it was the Big Bang. It all started with a click of the cosmic fingers, a huge explosion that gave rise to everything known and known. The Big Bang is not only the most popular cosmological theory of the last 50 years, but it is a minimal agreement between contemporary physics and the Western worldview of the origin (and the eventual end) of the Universe.
However, not all scientists agree and in this area it is especially relevant because the Big Bang theory, far from solving all the problems about the origin of the Universe, what it does is to throw an epistemological lock. That is to say: what it tells us is that there is a point beyond which we can never know anything. Juliano César Silva Neves, a physicist at the University of Campinas in Brazil, is convinced that those who insist on closing physics with the Big Bang are cosmological spoilers: the Big Bang not only was not the origin of everything, but rather possibly it did not even exist.
The Universe is an accordion
The idea that Neves exposes in General Relativity and Gravitation has nothing new: that the Universe is cyclical, a huge accordion of matter and time, and that therefore it is not necessary to resort to that almost mythical and remote moment called the Big Bang and, to demonstrate that this idea is sustainable, it uses an old model to describe black holes .
What do black holes have to do with the origin of the universe?” There are only two types of singularities in the universe,” says Neves: the Big Bang and what happens beyond the event horizon of black holes. If we are able to construct a model that solves one without resorting to obscure concepts, there is no reason why we can not build a model for the other.
The singularities does not exist
They are the perfect ‘equivalent’ to conceptualize what happened before Big Bang. And as Neves points out to support his thesis, not all explanatory models of holes need a singularity to explain them. In 1968, a physicist named James Bardeen proposed another solution . He published a way to describe holes that did not require that singularity: regular black holes.
At a more basic level, Bardeen pointed out that mass within a black hole could be described using a function that related density to distance from the center (without having to assume that it was homogeneous). That is, the mass behaves exactly as it did outside the hole only in a super-density context.
From the Black Holes to the origin of the Universe
Neves takes that model and uses it to explain the Big Bang without having to resort to a cosmological singularity. And the funny thing is that, applying the Bardeen model to the development of the Universe (that is, creating a model that not only takes into account time, but also volume) it is not necessary to resort to an exponential event to explain the process.
What emerges is an image of the Universe as “an eternal succession of universes with phases of alternate expansion and contraction, a cyclic universe,” Neves says. The task now is to find evidence that the universe bounces. That is to say, do not worry about what fits everything: we need to find the traces of the Universes spent in this.
It is not very likely that we find them and the theory (still) leaves much to be desired, but without a doubt, all attempts to break the ‘lock’ of the Big Bang are well received by those who never stop aspiring to go one step further there.