Physicists say a second Big Bang could have created dark matter

Two physicists at the University of Texas suggest dark matter is so elusive and mysterious because it has an entirely different origin to that of the Big Bang. They believe a second cosmic explosion may have occurred weeks after the initial formation of the universe.

Thred Media
3 min readMar 16, 2023

--

Hump day is the perfect time for a large dose of existentialism. So, how’s about we get stuck into the incomprehensible subject of dark matter.

The general cosmological theory, is that dark matter and dark energy could make up as much as 85% of the known universe — the only problem, is we can’t observe its existence directly. Thought to be composed of particles that do not reflect or emit light (hence the name), our forages using electromagnetic radiation have to-date been fruitless.

This chasm of frontier knowledge has existed for 100 years of obsession and frustration. What little we have gleaned, through mathematical calculations and visible reactions with the universe’s known matter, is that this ghostly wonder does in-fact exist, probably.

If you want to really delve into the experiments and peer back through the history of our meagre understanding, we wrote a comprehensive overview in 2019.

Our existing model of the cosmos assumes that both regular and dark matter were born during the Big Bang some 14bn years ago, give or take a few hundred million years. In this moment, a single point filled with unimaginably dense material supposedly unleashed a staggering exhalation and the universe rapidly expanded from there.

Within just three minutes the first protons, neutrons, electrons, and neutrinos had formed. Big Bang Nucleosynthesis (BBN) breathed cosmic gases, mostly helium and hydrogen, into existence, and consolidating atoms organised themselves into the first stars, planets, and galaxies.

This version of events has served our celestial studies well. Nevertheless, some are reluctant to accept that dark matter arose at this critical point, due to a lack of trace evidence and the fact that no non-gravitational interactions between the two materials have been recorded.

Within just three minutes the first protons, neutrons, electrons, and neutrinos had formed. Big Bang Nucleosynthesis (BBN) breathed cosmic gases, mostly helium and hydrogen, into existence, and consolidating atoms organised themselves into the first stars, planets, and galaxies.

This version of events has served our celestial studies well. Nevertheless, some are reluctant to accept that dark matter arose at this critical point, due to a lack of trace evidence and the fact that no non-gravitational interactions between the two materials have been recorded.

While regular matter quickly cooled into atoms, this substrate laid dormant for weeks before decaying and transforming its state, sparking the alternate scenario of the Dark Big Bang and its own mysterious matter.

‘The Dark Big Bang phase transition generates strong gravitational radiation,’ the team said in their study, before expressing optimism at the possibility of finding indicatory ripples in spacetime. Observations of ultra-dense stars known as pulsars are ongoing, though the study has yet to be peer reviewed.

‘We investigated the sensitivity of ongoing and upcoming pulsar timing array experiments to the gravitational wave signal from the Dark Big Bang,’ they revealed. ‘We found that already the ongoing IPTA run has an exciting discovery potential for Dark Big Bangs.’

Whether or not signals alone will be enough to add real credence to their hypothesis, there’s no denying the research is fascinating.

With future instruments, such as the enormous Square Kilometer Array, we could potentially discover far more about the speculative, yet captivating riddle that is dark matter.

Or, at the very least, confirm that we were on the money to begin with.

Originally written by Jamie Watts for Thred.

--

--