September 2024
A new theory presented in a paper in Journal of Cosmology and Astroparticle Physics offers an alternative to the big bang model, namely that the universe ‘bounces’ between a hot, dense phase and a state like the one we experience. This means that instead of a ‘big bang’, there have been multiple ‘big bounces’.
Dark matter has been explained before by the existence of primordial black holes, but this model holds that these original black holes are the remnant of a time before the big bang/big bounce caused by tiny disturbances during this development phase of the universe.
According to the theory, “the observable universe today is recycled from a previous universe”, writes Popular Mechanics magazine.
Interestingly, this new model resembles ancient metaphysical concepts. According to Hindu cosmology, the universe is ‘breathing’, meaning that there is a perpetual cycle of creation and destruction.
The timescales in Hindu cosmology correspond fairly well with modern science, but it also contends that the universe we inhabit is neither the first, nor the last.
A BBC guide describes the Hindu cycle of birth and death of the universe, the ‘breathing’, like this:
“For Hindus the universe was created by Brahma, the creator who made the universe out of himself. After Brahma created the world, it is the power of Vishnu which preserves the world and human beings. As part of the cycle of birth, life and death it is Shiva who will ultimately destroy the universe. This is not necessarily as bad as it might sound, because it allows Brahma to start the process of creation all over again.”
So, did the universe really begin only once, with the ‘big bang’? Or are we all part of an endless cosmic cycle?
The dominant theory of a ‘big bang’ plus ‘inflation’ (that the universe at the very beginning underwent a rapid inflation that lasted a fraction of a second) may explain phenomena like the cosmic background radiation and the age of the oldest stars. But it leaves other mysteries unresolved, such as the existence of dark matter and the ‘flatness problem’.
Without going too deeply into the cosmological oddities, the universe would appear more curved than it does if it was created the way the big bang plus inflation postulates. When you send out two parallel beams of photons, they ought to eventually cross each other and return to their starting point. But they don’t. Parallel lines stay parallel, which makes the universe we live in look flat.
The new theory claims to resolve that mystery.
“This cosmological scenario is free of the initial singularity problem present in inflationary cosmology, solving as well the flatness and horizon problems of the standard HBB [Hot Big Bang] theory”, the research team asserts in the paper.
Anders Bolling
