If they ask you what the beginning of the universe was, the Big Bang is the first answer that surely comes to mind.
There are scientists, however, who they question that that was the beginning.
Now a young researcher goes further and affirms that perhaps there was not even a beginning.
This is Bruno Bento, a researcher at the Department of Mathematical Sciences at the University of Liverpool, in the United Kingdom.
Bento is the co-author of an academic article titled “If time had no beginning”, which is still under review by other experts.
His theory differs from the traditional concept we have about the passage of time, it raises a past infinite and sees the Big Bang as one more event in a cosmos that has always existed.
What is Bento’s proposal and how does it challenge what we know about the evolution of the universe?
Beyond the singularity
Modern physics has two theories that help us explain the universe.
On one side is the quantum mechanics, which describes subatomic particles and interactions.
And on the other side is the general relativity, which works very well to explain the gravity that governs what happens in the macroscopic world.
The theory of general relativity leads us to 13.8 billion years back to the moments immediately after the Big Bang, when everything existed on tiny scales.
That Einstein theory, however, falls short when explaining what happened at the moment of the Big Bang, or what happened before.
This is what experts call the “singularity”, that is, the point at which the theory of relativity no longer serves to explain what is happening.
In that singularity, matter is so compressed that gravity becomes tremendously strong at subatomic scales.
So what would be needed to explain what happened during and before that singularity is a theory that unify quantum mechanics and general relativity.
This is what experts call a theory quantum of the gravity, in which gravity can be explained at the quantum level and helps describe what happens at those scales.
And this is where the Bento proposition comes in.
In his article, Bento draws on causal set theory, an approach to quantum gravity that holds that spacetime is made up of some building blocks, “Atoms of space-time”, that are forming elements.
In this way, the theory of causal sets solves the problem of singularity, because according to its view there cannot be nothing smaller than an atom of space-time.
“According to the theory of causal sets, what we feel as the passage of time corresponds to the birth of new elements of the causal set “, Bento tells BBC Mundo.
“What we call ‘now’ it is the birth of a new element ”.
We don’t have a beginning
Bento’s work starts from this idea to propose that causal sets have been formed infinitelyTherefore, the Big Bang would not be the beginning of the universe.
For Bento there is always something before, that is, the causal sets would be infinite in the past and the Big Bang would be only a particular moment in the evolution of the universe.
“Our work says that if causal sets are the answer, we we don’t necessarily have a beginning “says Bento.
The challenge that Bento proposes is to get rid of the idea of “sequence” in which one element gives rise to another.
Instead, he suggests thinking of a “Become asynchronous” in which the elements are born partially and not totally.
In his article, the researcher acknowledges that this idea of ”asynchronous becoming” sounds like a “fantasy riddle” and that it is “necessary to new kind of math to understand “asynchronous becoming” and its consequences in the nature of time ”.
Bento’s work “offers the first steps in establishing a mathematical understanding of the Big Bang and its possible prehistory ”, astrophysicist Niayesh Afshordi, a researcher at the Perimeter Institute of Theoretical Physics in Canada, who was not involved in this work, tells BBC Mundo.
Bento hopes that future experiments can try the consequences of models like the ones he proposes.