Dark matter in trouble again

Everyone loves a controversy. There is a new one brewing, and some astrophysicists are very unhappy because their pet paradigm is in trouble again.

Dark matter, the stuff that allegedly comprises up to 85% of the matter content of galaxies in the universe, has just hit another road block:

“ … three physicists claim their observations of empty patches of sky rule out one possible explanation of the strange substance—that it is made out of unusual particles called sterile neutrinos. But others argue the data show no such thing.”

So writes Adrian Cho in the online Science magazine titled “Physicists brawl over new dark matter claim”.¹ But sterile neutrinos are totally hypothetical. They are supposed to be new subatomic particles that do not interact with normal matter except that they can ‘mix’ with the other three real neutrinos. The idea is that these exotic neutrinos add a lot of otherwise-unobservable ‘dark’ matter to the halo of galaxies, therefore that extra matter solves the enigma of why stars move too fast around their galactic centres. It is also alleged that these exotic particles can decay into ordinary real neutrinos, and when they do, they emit an X-ray photon with a characteristic energy of 3.5 keV.

But a new analysis of old X-ray data of apparently blank regions between stars in the Milky Way galaxy and some nearby galaxies, just published in leading journal Science,² refutes the notion that these putative particles fill the void (both of knowledge concerning ‘dark matter’ as well as literally the apparently empty space). Other physicists disagree and claim the new results come from ‘cherry picking’ the data.

But the exact same data was used. One group could see the X-ray emission but those in the new study could not. Who do we believe?

Adrian Cho writes

“Alexey Boyarsky, an astroparticle theorist at Leiden University, is unconvinced. ‘I think this paper is wrong,’ he says. Boyarsky says he and his colleagues performed a similar, unpublished analysis in 2018³, also using images from XMM-Newton, and did see a 3.5-keV glow from the empty sky, just expected from peering through a halo of sterile neutrinos.”

If the theory is correct, this faint X-ray glow should be seen everywhere. But now we have specialist physicists brawling over whether they can see it. And the need to see it is indeed very real. Without dark matter filling the universe the big bang paradigm, and even a lot of astrophysics, is in serious trouble.

Why? It is not just relevant to the problem of what holds galaxies together—i.e. whether there is a significant deficiency of matter in spiral galaxies⁴ (which there is, according to standard Newtonian physics). The dark matter problem extends to all scales in the universe, including clusters, superclusters,⁵ and the whole universe itself.⁶ Dark matter is needed everywhere. Without it nothing in the universe as we see it could have formed naturalistically (Why is Dark Matter everywhere in the cosmos? A product of the Dark Side).

Without dark matter, galaxies and stars do not form naturalistically. Hence, dark matter has become the de facto ‘god of the gaps’ for astrophysics and cosmology (Stars just don’t form naturally—‘dark matter’ the ‘god of the gaps’ is needed). It is the new pagan god—the alleged creator of the universe. But like all false gods, in reality it just does not exist.

Let me end with a quote from one of the new study’s authors, Benjamin Safdi:

“I think that for most of the people in the community this is the end of the story.”¹

Dark matter is not observed. It does not exist!

Published: 19 May 2020

References and notes

Cho, A., Physicists brawl over new dark matter claim, sciencemag.org, 26 March 2020. Return to text.
Dessert, C., Rodd, N.L., and Safdi, B.R., The dark matter interpretation of the 3.5-keV line is inconsistent with blank-sky observations, Science 367(6485):1465–1467, 27 March 2020. Return to text.
Boyarsky, A., et al., Surface brightness profile of the 3.5 keV line in the Milky Way halo, 13 Feb. 2019; arxiv.org/abs/1812.10488. Return to text.
Dark matter in galaxies is claimed to comprise as much as 85% of the matter of a galaxy. Return to text.
In some cases it is claimed the dark matter content of clusters and superclusters is of order 99.9%. Return to text.
The common figure for the fraction of dark matter in the universe is about 24% of total mass/energy as compared to about 4% normal matter. That is about 7 times the amount of dark matter as normal matter. The rest of mass/energy content is claimed to be the other exotic stuff called dark energy, comprising about 72% of the total. Return to text.