It also says that, according to this quantum theory, the universe will never die.
If we imagine rewinding the expansion of the universe back in time, the galaxies we see all seem to converge on a single, infinitesimal point: the big bang singularity.
At this point, our current theory of gravity — Einstein’s general theory of relativity — predicts that the universe had an infinite density and temperature. This moment is sometimes sold as the beginning of the universe, the birth of matter, space and time. Such an interpretation, however, goes too far, because the infinite values indicate that general relativity itself breaks down.
To explain what really happened at the Big Bang, physicists must transcend relativity. We must develop a theory of quantum gravity, which would capture the fine structure of space/time to which relativity is blind.
According to one candidate for such a theory, loop quantum gravity, space is divided into atoms of volume and has a finite capacity to store matter and energy, thereby preventing true singularities from existing.
If so, time may extend before the bang. The pre-bang universe may have undergone a catastrophic implosion that reached a point of maximum density and then reversed. In short, a big crunch may have led to a big bounce and then a big bang.
It's interesting that ‘loop gravity’ recognises much more of a role for electromagnetism. The ‘loops’ of the theory are analogues of electric and magnetic fields tied into knots, and then they apply quantum principles to them.
Unlike Newton's idea of the universe winding down like a clock, the headline says: "Quantum gravity theory predicts the universe will never die". Ancient mythology also tells us that Time is infinite, and therefore not really time at all, just a series of Nows.
But it stands to reason. If there was a Big Bang or Big Bounce, what was there in the first place to go Bang or to Bounce? Something must have been there. The 'crunch' they're calling it. So how did the crunch get there? And in any case, where is ‘there’ in the absence of a universe? And if ‘there’ is somewhere ...... and so on....
It's not rocket science!