News and Views

Comment on “DES map shows a smoother distribution of matter than expected: a possible explanation”


News and Views on RAA 2021 Vol. 21, No. 10, 241

Author: Prof. Valeriy Astapenko

  • Moscow Institute of Physics and Technology (National Research University), Dolgoprudny, Moscow Region, 141701, Russia, Email: astval[at]

This paper is excellent for several reasons. It provides a convincing explanation to the recent puzzling observational results by Jeffrey et al (2021), who found that the distribution of dark matter in the Universe is by several percent less clumpy than what is predicted by general relativity. The results by Jeffrey et al (2021) were considered as the call for new physical laws beyond Einstein’s gravity. However, Oks (2021b) proposed a relatively simple explanation that does not require any new physical laws.

The explanation is based on the Second Flavor of Hydrogen Atoms (SFHA), whose existence has a proof from atomic experiments (Oks 2001). Moreover, there was already also an astrophysical proof: the existence of SFHA helped in explaining (Oks 2020) other recent puzzling astrophysical observations by Bowman et al (2018) concerning the redshifted 21 cm radio linefrom the early Universe.

Oks (2021b) provided not only a qualitative, but also a quantitative explanation of the observational results by Jeffrey et al (2021). Combined with the explanation of the observations by Bowman et al (2018), this reinforces the status of SFHA as the most natural candidate for dark matter or for a part of it. It is remarkable that the theoretical discovery of SFHA by Oks (2001) was based on standard quantum mechanics without any change to the physical laws, so that the SFHA, as the dark matter candidate, does not need to go beyond the Standard Model – in distinction to other hypotheses explaining dark matter.

Last but not least: Oks (2021b) mentioned that there is a slight difference between the SFHA and usual hydrogen atoms in cross-sections of charge exchange with an incoming proton, as he showed in his other paper (Oks 2021a). This can be utilized for finding yet other evidence for the existence of SFHA from atomic experiments. It could be sufficient to re-analyze the already available experimental data on charge exchange of hydrogen atoms with incoming protons. If in these experiments a slight difference was found between the experimental cross-section of charge exchange and the corresponding predictions by previous theories, it is possible that this was not considered as warranting a further analysis at that time. Now, while re-analyzing these experimental data by taking into account the Oks (2021a) paper, it might be achievable to not only discover additional evidence of the existence of the SFHA, but also to estimate its percentage in the mixture of hydrogen atoms in our environment.


  1. Bowman, J.D.; Rogers, A.E.E.; Monsalve, R.A.; Mozdzen, T.J.; Mahesh, N. An Absorption Profile Centred at 78 Megahertz in the Sky-Averaged Spectrum. Nature 2018, 555, 67-70

  2. Jeffrey, N. et al. Dark Energy Survey Year 3 Results: Curved-Sky Weak Lensing Mass Map Reconstruction. MNRAS 2021, 505, 4626-4645

  3. Oks, E. High-Energy Tail of the Linear Momentum Distribution in the Ground State of Hydrogen Atoms or Hydrogen-like Ions. J. Phys. B: At. Mol. Opt. Phys., 2001, 34, 2235-2243.

  4. Oks, E. Alternative Kind of Hydrogen Atoms as a Possible Explanation of the Latest Puzzling Observation of the 21 cm Radio Line from the Early Universe. Research in Astronomy and Astrophysics 2020a, 20, 109.

  5. Oks, E. Classical Description of Resonant Charge Exchange Involving the Second Flavor of Hydrogen Atoms. Atoms 2021a, 9, 41.

  6. Oks, E. DES map shows a smoother distribution of matter than expected: a possible explanation. Research in Astronomy and Astrophysics 2021b, 10, 241.